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Sample records for tissue-like assemblies target

  1. Three-Dimensionally Engineered Normal Human Broncho-epithelial Tissue-Like Assemblies: Target Tissues for Human Respiratory Viral Infections

    Science.gov (United States)

    Goodwin, T. J.; McCarthy, M.; Lin, Y-H

    2006-01-01

    In vitro three-dimensional (3D) human broncho-epithelial (HBE) tissue-like assemblies (3D HBE TLAs) from this point forward referred to as TLAs were engineered in Rotating Wall Vessel (RWV) technology to mimic the characteristics of in vivo tissues thus providing a tool to study human respiratory viruses and host cell interactions. The TLAs were bioengineered onto collagen-coated cyclodextran microcarriers using primary human mesenchymal bronchial-tracheal cells (HBTC) as the foundation matrix and an adult human bronchial epithelial immortalized cell line (BEAS-2B) as the overlying component. The resulting TLAs share significant characteristics with in vivo human respiratory epithelium including polarization, tight junctions, desmosomes, and microvilli. The presence of tissue-like differentiation markers including villin, keratins, and specific lung epithelium markers, as well as the production of tissue mucin, further confirm these TLAs differentiated into tissues functionally similar to in vivo tissues. Increasing virus titers for human respiratory syncytial virus (wtRSVA2) and parainfluenza virus type 3 (wtPIV3 JS) and the detection of membrane bound glycoproteins over time confirm productive infections with both viruses. Therefore, TLAs mimic aspects of the human respiratory epithelium and provide a unique capability to study the interactions of respiratory viruses and their primary target tissue independent of the host's immune system.

  2. Engineered human broncho-epithelial tissue-like assemblies

    Science.gov (United States)

    Goodwin, Thomas J. (Inventor)

    2012-01-01

    Three-dimensional human broncho-epithelial tissue-like assemblies (TLAs) are produced in a rotating wall vessel (RWV) with microcarriers by coculturing mesenchymal bronchial-tracheal cells (BTC) and bronchial epithelium cells (BEC). These TLAs display structural characteristics and express markers of in vivo respiratory epithelia. TLAs are useful for screening compounds active in lung tissues such as antiviral compounds, cystic fibrosis treatments, allergens, and cytotoxic compounds.

  3. Design strategies for self-assembly of discrete targets

    International Nuclear Information System (INIS)

    Madge, Jim; Miller, Mark A.

    2015-01-01

    Both biological and artificial self-assembly processes can take place by a range of different schemes, from the successive addition of identical building blocks to hierarchical sequences of intermediates, all the way to the fully addressable limit in which each component is unique. In this paper, we introduce an idealized model of cubic particles with patterned faces that allows self-assembly strategies to be compared and tested. We consider a simple octameric target, starting with the minimal requirements for successful self-assembly and comparing the benefits and limitations of more sophisticated hierarchical and addressable schemes. Simulations are performed using a hybrid dynamical Monte Carlo protocol that allows self-assembling clusters to rearrange internally while still providing Stokes-Einstein-like diffusion of aggregates of different sizes. Our simulations explicitly capture the thermodynamic, dynamic, and steric challenges typically faced by self-assembly processes, including competition between multiple partially completed structures. Self-assembly pathways are extracted from the simulation trajectories by a fully extendable scheme for identifying structural fragments, which are then assembled into history diagrams for successfully completed target structures. For the simple target, a one-component assembly scheme is most efficient and robust overall, but hierarchical and addressable strategies can have an advantage under some conditions if high yield is a priority

  4. Targeted assembly of short sequence reads.

    Directory of Open Access Journals (Sweden)

    René L Warren

    Full Text Available As next-generation sequence (NGS production continues to increase, analysis is becoming a significant bottleneck. However, in situations where information is required only for specific sequence variants, it is not necessary to assemble or align whole genome data sets in their entirety. Rather, NGS data sets can be mined for the presence of sequence variants of interest by localized assembly, which is a faster, easier, and more accurate approach. We present TASR, a streamlined assembler that interrogates very large NGS data sets for the presence of specific variants by only considering reads within the sequence space of input target sequences provided by the user. The NGS data set is searched for reads with an exact match to all possible short words within the target sequence, and these reads are then assembled stringently to generate a consensus of the target and flanking sequence. Typically, variants of a particular locus are provided as different target sequences, and the presence of the variant in the data set being interrogated is revealed by a successful assembly outcome. However, TASR can also be used to find unknown sequences that flank a given target. We demonstrate that TASR has utility in finding or confirming genomic mutations, polymorphisms, fusions and integration events. Targeted assembly is a powerful method for interrogating large data sets for the presence of sequence variants of interest. TASR is a fast, flexible and easy to use tool for targeted assembly.

  5. Target Assembly Facility

    Data.gov (United States)

    Federal Laboratory Consortium — The Target Assembly Facility integrates new armor concepts into actual armored vehicles. Featuring the capability ofmachining and cutting radioactive materials, it...

  6. NIF Target Assembly Metrology Methodology and Results

    Energy Technology Data Exchange (ETDEWEB)

    Alger, E. T. [General Atomics, San Diego, CA (United States); Kroll, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Dzenitis, E. G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Montesanti, R. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Hughes, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Swisher, M. [IAP, Livermore, CA (United States); Taylor, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Segraves, K. [IAP, Livermore, CA (United States); Lord, D. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Reynolds, J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Castro, C. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Edwards, G. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2011-01-01

    During our inertial confinement fusion (ICF) experiments at the National Ignition Facility (NIF) we require cryogenic targets at the 1-cm scale to be fabricated, assembled, and metrologized to micron-level tolerances. During assembly of these ICF targets, there are physical dimensmetrology is completed using optical coordinate measurement machines that provide repeatable measurements with micron precision, while also allowing in-process data collection for absolute accuracy in assembly. To date, 51 targets have been assembled and metrologized, and 34 targets have been successfully fielded on NIF relying on these metrology data. In the near future, ignition experiments on NIF will require tighter tolerances and more demanding target assembly and metrology capability. Metrology methods, calculations, and uncertainty estimates will be discussed. Target diagnostic port alignment, target position, and capsule location results will be reviewed for the 2009 Energetics Campaign. The information is presented via control charts showing the effect of process improvements that were made during target production. Certain parameters, including capsule position, met the 2009 campaign specifications but will have much tighter requirements in the future. Finally, in order to meet these new requirements assembly process changes and metrology capability upgrades will be necessary.

  7. High-throughput bone and cartilage micropellet manufacture, followed by assembly of micropellets into biphasic osteochondral tissue.

    Science.gov (United States)

    Babur, Betul Kul; Futrega, Kathryn; Lott, William B; Klein, Travis Jacob; Cooper-White, Justin; Doran, Michael Robert

    2015-09-01

    Engineered biphasic osteochondral tissues may have utility in cartilage defect repair. As bone-marrow-derived mesenchymal stem/stromal cells (MSC) have the capacity to make both bone-like and cartilage-like tissues, they are an ideal cell population for use in the manufacture of osteochondral tissues. Effective differentiation of MSC to bone-like and cartilage-like tissues requires two unique medium formulations and this presents a challenge both in achieving initial MSC differentiation and in maintaining tissue stability when the unified osteochondral tissue is subsequently cultured in a single medium formulation. In this proof-of-principle study, we used an in-house fabricated microwell platform to manufacture thousands of micropellets formed from 166 MSC each. We then characterized the development of bone-like and cartilage-like tissue formation in the micropellets maintained for 8-14 days in sequential combinations of osteogenic or chondrogenic induction medium. When bone-like or cartilage-like micropellets were induced for only 8 days, they displayed significant phenotypic changes when the osteogenic or chondrogenic induction medium, respectively, was swapped. Based on these data, we developed an extended 14-day protocol for the pre-culture of bone-like and cartilage-like micropellets in their respective induction medium. Unified osteochondral tissues were formed by layering 12,000 osteogenic micropellets and 12,000 chondrogenic micropellets into a biphasic structure and then further culture in chondrogenic induction medium. The assembled tissue was cultured for a further 8 days and characterized via histology. The micropellets had amalgamated into a continuous structure with distinctive bone-like and cartilage-like regions. This proof-of-concept study demonstrates the feasibility of micropellet assembly for the formation of osteochondral-like tissues for possible use in osteochondral defect repair.

  8. Three-dimensional bioprinting using self-assembling scalable scaffold-free “tissue strands” as a new bioink

    Science.gov (United States)

    Yu, Yin; Moncal, Kazim K.; Li, Jianqiang; Peng, Weijie; Rivero, Iris; Martin, James A.; Ozbolat, Ibrahim T.

    2016-01-01

    Recent advances in bioprinting have granted tissue engineers the ability to assemble biomaterials, cells, and signaling molecules into anatomically relevant functional tissues or organ parts. Scaffold-free fabrication has recently attracted a great deal of interest due to the ability to recapitulate tissue biology by using self-assembly, which mimics the embryonic development process. Despite several attempts, bioprinting of scale-up tissues at clinically-relevant dimensions with closely recapitulated tissue biology and functionality is still a major roadblock. Here, we fabricate and engineer scaffold-free scalable tissue strands as a novel bioink material for robotic-assisted bioprinting technologies. Compare to 400 μm-thick tissue spheroids bioprinted in a liquid delivery medium into confining molds, near 8 cm-long tissue strands with rapid fusion and self-assemble capabilities are bioprinted in solid form for the first time without any need for a scaffold or a mold support or a liquid delivery medium, and facilitated native-like scale-up tissues. The prominent approach has been verified using cartilage strands as building units to bioprint articular cartilage tissue. PMID:27346373

  9. Self-Organization and the Self-Assembling Process in Tissue Engineering

    Science.gov (United States)

    Eswaramoorthy, Rajalakshmanan; Hadidi, Pasha; Hu, Jerry C.

    2015-01-01

    In recent years, the tissue engineering paradigm has shifted to include a new and growing subfield of scaffoldless techniques which generate self-organizing and self-assembling tissues. This review aims to provide a cogent description of this relatively new research area, with special emphasis on applications toward clinical use and research models. Particular emphasis is placed on providing clear definitions of self-organization and the self-assembling process, as delineated from other scaffoldless techniques in tissue engineering and regenerative medicine. Significantly, during formation, self-organizing and self-assembling tissues display biological processes similar to those that occur in vivo. These help lead to the recapitulation of native tissue morphological structure and organization. Notably, functional properties of these tissues also approach native tissue values; some of these engineered tissues are already in clinical trials. This review aims to provide a cohesive summary of work in this field, and to highlight the potential of self-organization and the self-assembling process to provide cogent solutions to current intractable problems in tissue engineering. PMID:23701238

  10. A triple axes multiple target holder assembly

    International Nuclear Information System (INIS)

    Tribedi, L.C.; Narvekar, S.D.; Pillay, R.G.; Tandon, P.N.

    1993-01-01

    We have designed and fabricated a rotatable target holder assembly capable of accommodating 27 targets. The target foils are mounted along two concentric circles on a ss wheel. On the outer circle 18 targets can be mounted each 20deg apart, and on the inner circle the remaining targets are positioned each 40deg apart. The self supporting or carbon backed targets are mounted on thin frames and are placed concentrically at the targets are mounted on thin frames and are placed concentrically at the target position on the wheel. Three degrees of freedom are provided to the target holder assembly. (author). 1 fig

  11. Quantitative self-assembly prediction yields targeted nanomedicines

    Science.gov (United States)

    Shamay, Yosi; Shah, Janki; Işık, Mehtap; Mizrachi, Aviram; Leibold, Josef; Tschaharganeh, Darjus F.; Roxbury, Daniel; Budhathoki-Uprety, Januka; Nawaly, Karla; Sugarman, James L.; Baut, Emily; Neiman, Michelle R.; Dacek, Megan; Ganesh, Kripa S.; Johnson, Darren C.; Sridharan, Ramya; Chu, Karen L.; Rajasekhar, Vinagolu K.; Lowe, Scott W.; Chodera, John D.; Heller, Daniel A.

    2018-02-01

    Development of targeted nanoparticle drug carriers often requires complex synthetic schemes involving both supramolecular self-assembly and chemical modification. These processes are generally difficult to predict, execute, and control. We describe herein a targeted drug delivery system that is accurately and quantitatively predicted to self-assemble into nanoparticles based on the molecular structures of precursor molecules, which are the drugs themselves. The drugs assemble with the aid of sulfated indocyanines into particles with ultrahigh drug loadings of up to 90%. We devised quantitative structure-nanoparticle assembly prediction (QSNAP) models to identify and validate electrotopological molecular descriptors as highly predictive indicators of nano-assembly and nanoparticle size. The resulting nanoparticles selectively targeted kinase inhibitors to caveolin-1-expressing human colon cancer and autochthonous liver cancer models to yield striking therapeutic effects while avoiding pERK inhibition in healthy skin. This finding enables the computational design of nanomedicines based on quantitative models for drug payload selection.

  12. The self-assembling process and applications in tissue engineering

    Science.gov (United States)

    Lee, Jennifer K.; Link, Jarrett M.; Hu, Jerry C. Y.; Athanasiou, Kyriacos A.

    2018-01-01

    Tissue engineering strives to create neotissues capable of restoring function. Scaffold-free technologies have emerged that can recapitulate native tissue function without the use of an exogenous scaffold. This chapter will survey, in particular, the self-assembling and self-organization processes as scaffold-free techniques. Characteristics and benefits of each process are described, and key examples of tissues created using these scaffold-free processes are examined to provide guidance for future tissue engineering developments. This chapter aims to explore the potential of self-assembly and self-organization scaffold-free approaches, detailing the recent progress in the in vitro tissue engineering of biomimetic tissues with these methods, toward generating functional tissue replacements. PMID:28348174

  13. Endosialin and Associated Protein Expression in Soft Tissue Sarcomas: A Potential Target for Anti-Endosialin Therapeutic Strategies

    Directory of Open Access Journals (Sweden)

    Daniel J. O’Shannessy

    2016-01-01

    Full Text Available Endosialin (CD248, TEM-1 is expressed in pericytes, tumor vasculature, tumor fibroblasts, and some tumor cells, including sarcomas, with limited normal tissue expression, and appears to play a key role in tumor-stromal interactions, including angiogenesis. Monoclonal antibodies targeting endosialin have entered clinical trials, including soft tissue sarcomas. We evaluated a cohort of 94 soft tissue sarcoma samples to assess the correlation between gene expression and protein expression by immunohistochemistry for endosialin and PDGFR-β, a reported interacting protein, across available diagnoses. Correlations between the expression of endosialin and 13 other genes of interest were also examined. Within cohorts of soft tissue diagnoses assembled by tissue type (liposarcoma, leiomyosarcoma, undifferentiated sarcoma, and other, endosialin expression was significantly correlated with a better outcome. Endosialin expression was highest in liposarcomas and lowest in leiomyosarcomas. A robust correlation between protein and gene expression data for both endosialin and PDGFR-β was observed. Endosialin expression positively correlated with PDGFR-β and heparin sulphate proteoglycan 2 and negatively correlated with carbonic anhydrase IX. Endosialin likely interacts with a network of extracellular and hypoxia activated proteins in sarcomas and other tumor types. Since expression does vary across histologic groups, endosialin may represent a selective target in soft tissue sarcomas.

  14. Bioreactor-induced mesenchymal progenitor cell differentiation and elastic fiber assembly in engineered vascular tissues.

    Science.gov (United States)

    Lin, Shigang; Mequanint, Kibret

    2017-09-01

    In vitro maturation of engineered vascular tissues (EVT) requires the appropriate incorporation of smooth muscle cells (SMC) and extracellular matrix (ECM) components similar to native arteries. To this end, the aim of the current study was to fabricate 4mm inner diameter vascular tissues using mesenchymal progenitor cells seeded into tubular scaffolds. A dual-pump bioreactor operating either in perfusion or pulsatile perfusion mode was used to generate physiological-like stimuli to promote progenitor cell differentiation, extracellular elastin production, and tissue maturation. Our data demonstrated that pulsatile forces and perfusion of 3D tubular constructs from both the lumenal and ablumenal sides with culture media significantly improved tissue assembly, effectively inducing mesenchymal progenitor cell differentiation to SMCs with contemporaneous elastin production. With bioreactor cultivation, progenitor cells differentiated toward smooth muscle lineage characterized by the expression of smooth muscle (SM)-specific markers smooth muscle alpha actin (SM-α-actin) and smooth muscle myosin heavy chain (SM-MHC). More importantly, pulsatile perfusion bioreactor cultivation enhanced the synthesis of tropoelastin and its extracellular cross-linking into elastic fiber compared with static culture controls. Taken together, the current study demonstrated progenitor cell differentiation and vascular tissue assembly, and provides insights into elastin synthesis and assembly to fibers. Incorporation of elastin into engineered vascular tissues represents a critical design goal for both mechanical and biological functions. In the present study, we seeded porous tubular scaffolds with multipotent mesenchymal progenitor cells and cultured in dual-pump pulsatile perfusion bioreactor. Physiological-like stimuli generated by bioreactor not only induced mesenchymal progenitor cell differentiation to vascular smooth muscle lineage but also actively promoted elastin synthesis and

  15. pH-Sensitive Reversible Programmed Targeting Strategy by the Self-Assembly/Disassembly of Gold Nanoparticles.

    Science.gov (United States)

    Ma, Jinlong; Hu, Zhenpeng; Wang, Wei; Wang, Xinyu; Wu, Qiang; Yuan, Zhi

    2017-05-24

    A reversible programmed targeting strategy could achieve high tumor accumulation due to its long blood circulation time and high cellular internalization. Here, targeting ligand-modified poly(ethylene glycol) (PEG-ligand), dibutylamines (Bu), and pyrrolidinamines (Py) were introduced on the surface of gold nanoparticles (Au NPs) for reversible shielding/deshielding of the targeting ligands by pH-responsive self-assembly. Hydrophobic interaction and steric repulsion are the main driving forces for the self-assembly/disassembly of Au NPs. The precise self-assembly (pH ≥ 7.2) and disassembly (pH ≤ 6.8) of Au NPs with different ligands could be achieved by fine-tuning the modifying molar ratio of Bu and Py (R m ), which followed the formula R m = 1/(-0.0013X 2 + 0.0323X + 1), in which X is the logarithm of the partition coefficient of the targeting ligand. The assembled/disassembled behavior of Au NPs at pH 7.2 and 6.8 was confirmed by transmission electron microscopy and dynamic light scattering. Enzyme-linked immunosorbent assays and cellular uptake studies showed that the ligands could be buried inside the assembly and exposed when disassembled. More importantly, this process was reversible, which provides the possibility of prolonging blood circulation by shielding ligands associated with the NPs that were effused from tumor tissue.

  16. Microgravity Analogues of Herpes Virus Pathogenicity: Human Cytomegalovirus (hCMV) and Varicella Zoster (VZV) Infectivity in Human Tissue Like Assemblies (TLAs)

    Science.gov (United States)

    Goodwin, T. J.; McCarthy, M.; Albrecht, T.; Cohrs, R.

    2009-01-01

    The old adage we are our own worst enemies may perhaps be the most profound statement ever made when applied to man s desire for extraterrestrial exploration and habitation of Space. Consider the immune system protects the integrity of the entire human physiology and is comprised of two basic elements the adaptive or circulating and the innate immune system. Failure of the components of the adaptive system leads to venerability of the innate system from opportunistic microbes; viral, bacteria, and fungal, which surround us, are transported on our skin, and commonly inhabit the human physiology as normal and imunosuppressed parasites. The fine balance which is maintained for the preponderance of our normal lives, save immune disorders and disease, is deregulated in microgravity. Thus analogue systems to study these potential Risks are essential for our progress in conquering Space exploration and habitation. In this study we employed two known physiological target tissues in which the reactivation of hCMV and VZV occurs, human neural and lung systems created for the study and interaction of these herpes viruses independently and simultaneously on the innate immune system. Normal human neural and lung tissue analogues called tissue like assemblies (TLAs) were infected with low MOIs of approximately 2 x 10(exp -5) pfu hCMV or VZV and established active but prolonged low grade infections which spanned .7-1.5 months in length. These infections were characterized by the ability to continuously produce each of the viruses without expiration of the host cultures. Verification and quantification of viral replication was confirmed via RT_PCR, IHC, and confocal spectral analyses of the respective essential viral genomes. All host TLAs maintained the ability to actively proliferate throughout the entire duration of the experiments as is analogous to normal in vivo physiological conditions. These data represent a significant advance in the ability to study the triggering

  17. Artificial muscle-like function from hierarchical supramolecular assembly of photoresponsive molecular motors.

    Science.gov (United States)

    Chen, Jiawen; Leung, Franco King-Chi; Stuart, Marc C A; Kajitani, Takashi; Fukushima, Takanori; van der Giessen, Erik; Feringa, Ben L

    2018-02-01

    A striking feature of living systems is their ability to produce motility by amplification of collective molecular motion from the nanoscale up to macroscopic dimensions. Some of nature's protein motors, such as myosin in muscle tissue, consist of a hierarchical supramolecular assembly of very large proteins, in which mechanical stress induces a coordinated movement. However, artificial molecular muscles have often relied on covalent polymer-based actuators. Here, we describe the macroscopic contractile muscle-like motion of a supramolecular system (comprising 95% water) formed by the hierarchical self-assembly of a photoresponsive amphiphilic molecular motor. The molecular motor first assembles into nanofibres, which further assemble into aligned bundles that make up centimetre-long strings. Irradiation induces rotary motion of the molecular motors, and propagation and accumulation of this motion lead to contraction of the fibres towards the light source. This system supports large-amplitude motion, fast response, precise control over shape, as well as weight-lifting experiments in water and air.

  18. Artificial muscle-like function from hierarchical supramolecular assembly of photoresponsive molecular motors

    Science.gov (United States)

    Chen, Jiawen; Leung, Franco King-Chi; Stuart, Marc C. A.; Kajitani, Takashi; Fukushima, Takanori; van der Giessen, Erik; Feringa, Ben L.

    2018-02-01

    A striking feature of living systems is their ability to produce motility by amplification of collective molecular motion from the nanoscale up to macroscopic dimensions. Some of nature's protein motors, such as myosin in muscle tissue, consist of a hierarchical supramolecular assembly of very large proteins, in which mechanical stress induces a coordinated movement. However, artificial molecular muscles have often relied on covalent polymer-based actuators. Here, we describe the macroscopic contractile muscle-like motion of a supramolecular system (comprising 95% water) formed by the hierarchical self-assembly of a photoresponsive amphiphilic molecular motor. The molecular motor first assembles into nanofibres, which further assemble into aligned bundles that make up centimetre-long strings. Irradiation induces rotary motion of the molecular motors, and propagation and accumulation of this motion lead to contraction of the fibres towards the light source. This system supports large-amplitude motion, fast response, precise control over shape, as well as weight-lifting experiments in water and air.

  19. Investigation of IFMIF target assembly structure design

    International Nuclear Information System (INIS)

    Ida, Mizuho; Nakamura, Hiroo; Sugimoto, Masayoshi; Yamamura, Toshio

    2006-10-01

    In the International Fusion Materials Irradiation Facility (IFMIF), the back-wall of target assembly is the part suffered the highest neutron-flux. The back-wall and the assembly are designed to have lips for cutting/welding at the back-wall replacement. To reduce thermal stress and deformation of the back-wall under neutron irradiation, contact pressure between the back-wall and the assembly is one of dominant factors. Therefore, an investigation was performed for feasible clamping pressure of a mechanical clamp set in limited space around the back-wall. It was clarified that the clamp can give a pressure difference up to 0.4 MPa between the contact pressure and atmosphere pressure in the test cell room. Also a research was performed for the dissimilar metal welding in the back-wall. Use of 309 steel was found adequate as the intermediate filler metal through the research of previous welding. Maintaining a temperature of the target assembly so as to avoid a freezing of liquid lithium is needed at the lithium charge into the loop before the beam injection. The assembly is covered with thermal insulation. Therefore, a research and an investigation were performed for compact and light thermal-insulation effective even under helium (i.e. high heat-conduction) condition of the test cell room. The result was as follows; in the case that a thermal conductivity 0.008 W/m·K of one of found insulation materials is available in the temperature range up to 300degC of the IFMIF target assembly, needed thickness and weight of the insulation were respectively only 8.2 mm and 32 kg. Also a research was performed for high-heat-density heaters to maintain temperature of the back-wall which can not be cover with insulation due to limited space. A heater made of silicon-nitride was found to be adequate. Total heat of 8.4 kW on the back-wall was found to be achievable through an investigations of heater arrange. Also an investigation was performed for remote-handling device to

  20. A targeted nanoglobular contrast agent from host-guest self-assembly for MR cancer molecular imaging.

    Science.gov (United States)

    Zhou, Zhuxian; Han, Zhen; Lu, Zheng-Rong

    2016-04-01

    The clinical application of nanoparticular Gd(III) based contrast agents for tumor molecular MRI has been hindered by safety concerns associated with prolonged tissue retention, although they can produce strong tumor enhancement. In this study, a targeted well-defined cyclodextrin-based nanoglobular contrast agent was developed through self-assembly driven by host-guest interactions for safe and effective cancer molecular MRI. Multiple β-cyclodextrins attached POSS (polyhedral oligomeric silsesquioxane) nanoglobule was used as host molecule. Adamantane-modified macrocyclic Gd(III) contrast agent, cRGD (cyclic RGDfK peptide) targeting ligand and fluorescent probe was used as guest molecules. The targeted host-guest nanoglobular contrast agent cRGD-POSS-βCD-(DOTA-Gd) specifically bond to αvβ3 integrin in malignant 4T1 breast tumor and provided greater contrast enhancement than the corresponding non-targeted agent. The agent also provided significant fluorescence signal in tumor tissue. The histological analysis of the tumor tissue confirmed its specific and effective targeting to αvβ3 integrin. The targeted imaging agent has a potential for specific cancer molecular MR and fluorescent imaging. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Collagen like peptide bioconjugates for targeted drug delivery applications

    Science.gov (United States)

    Luo, Tianzhi

    the coil/globule conformational transition of the PDEGMEMA building block above its LCST with stabilization of the nanostructures by the hydrophilic CLP. To the best of our knowledge, this is the first report on such assembled nanostructures from collagen-like peptide containing copolymers. Due to the strong propensity for CLPs to bind to natural collagen via strand invasion processes, these nanosized vesicles may be used as drug carriers for targeted delivery. In addition to synthetic polymers, the collagen like peptide is then conjugated with a thermoresponsive elastin-like peptide (ELP). The resulting ELP-CLP diblock conjugates show a remarkable reduction in the inverse transition temperature of the ELP domain, attributed to the anchoring effect of the CLP triple helix. The lower transition temperature of the conjugate enables facile formation of well-defined vesicles at physiological temperature and the unexpected resolubilization of the vesicles at elevated temperatures upon unfolding of the CLP domain. Given the ability of CLPs to modify collagens, this work provides not only a simple and versatile avenue for controlling the inverse transition behavior of elastin-like peptides, but also suggest future opportunities for these thermoresponsive nanostructures in biologically relevant environments. In the last section, the potential of using the ELP-CLP nanoparticles as drug delivery vehicles for targeting collagen containing matrices is evaluated. A sustained release of clinically relevant amount of encapsulated modelled drug is achieved within three weeks, followed by a thermally controlled burst release. As expected, the ELP-CLP nanoparticles show strong retention on collagen substrate, via specific binding through collagen triple helix hybridization. Additionally, cell viability and proliferation studies using fibroblasts and chondrocytes suggest the nanoparticles are non-cytotoxic. Additionally, almost no TNF-alpha expression from macrophages is observed

  2. Fabrication of Thermo-Responsive Molecular Layers from Self-Assembling Elastin-Like Oligopeptides Containing Cell-Binding Domain for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Tomoyuki Koga

    2015-01-01

    Full Text Available Novel thermo-responsive elastin-like oligopeptides containing cell-binding epitope (Arg-Gly-Asp-Ser sequence; arginine-glycine-aspartic acid-serine (RGDS-elastin-like peptides (ELP and RGDS-deg-ELP; were newly prepared as building blocks of self-assembled molecular layer for artificial extra cellular matrix. A detailed analysis of the conformation of the oligo(ELPs in water and their self-assembling behavior onto hydrophobic surfaces were performed by using circular dichroism, Fourier transform infrared spectroscopy (FTIR, atomic force microscopy and water contact angle measurements. The experimental results revealed that both oligo(ELPs self-assembled onto hydrophobic surfaces and formed molecular layers based on their thermo-responsive conformational change from hydrous random coil to dehydrated β-turn structure. Effective cell adhesion and spreading behaviors were observed on these self-assembled oligo(ELP layers. In addition, attached cells were found to be recovered successfully as a cell-sheet by temperature-induced disassembly of oligo(ELP layer. This achievement provides an important insight to construct novel oligopeptide-based nano-surfaces for the design of smart artificial extra-cellular matrix.

  3. Target and Tissue Selectivity Prediction by Integrated Mechanistic Pharmacokinetic-Target Binding and Quantitative Structure Activity Modeling.

    Science.gov (United States)

    Vlot, Anna H C; de Witte, Wilhelmus E A; Danhof, Meindert; van der Graaf, Piet H; van Westen, Gerard J P; de Lange, Elizabeth C M

    2017-12-04

    Selectivity is an important attribute of effective and safe drugs, and prediction of in vivo target and tissue selectivity would likely improve drug development success rates. However, a lack of understanding of the underlying (pharmacological) mechanisms and availability of directly applicable predictive methods complicates the prediction of selectivity. We explore the value of combining physiologically based pharmacokinetic (PBPK) modeling with quantitative structure-activity relationship (QSAR) modeling to predict the influence of the target dissociation constant (K D ) and the target dissociation rate constant on target and tissue selectivity. The K D values of CB1 ligands in the ChEMBL database are predicted by QSAR random forest (RF) modeling for the CB1 receptor and known off-targets (TRPV1, mGlu5, 5-HT1a). Of these CB1 ligands, rimonabant, CP-55940, and Δ 8 -tetrahydrocanabinol, one of the active ingredients of cannabis, were selected for simulations of target occupancy for CB1, TRPV1, mGlu5, and 5-HT1a in three brain regions, to illustrate the principles of the combined PBPK-QSAR modeling. Our combined PBPK and target binding modeling demonstrated that the optimal values of the K D and k off for target and tissue selectivity were dependent on target concentration and tissue distribution kinetics. Interestingly, if the target concentration is high and the perfusion of the target site is low, the optimal K D value is often not the lowest K D value, suggesting that optimization towards high drug-target affinity can decrease the benefit-risk ratio. The presented integrative structure-pharmacokinetic-pharmacodynamic modeling provides an improved understanding of tissue and target selectivity.

  4. Activation of Toll-like receptors nucleates assembly of the MyDDosome signaling hub.

    Science.gov (United States)

    Latty, Sarah Louise; Sakai, Jiro; Hopkins, Lee; Verstak, Brett; Paramo, Teresa; Berglund, Nils A; Cammorota, Eugenia; Cicuta, Pietro; Gay, Nicholas J; Bond, Peter J; Klenerman, David; Bryant, Clare E

    2018-01-24

    Infection and tissue damage induces assembly of supramolecular organizing centres (SMOCs)), such as the Toll-like receptor (TLR) MyDDosome, to co-ordinate inflammatory signaling. SMOC assembly is thought to drive digital all-or-none responses, yet TLR activation by diverse microbes induces anything from mild to severe inflammation. Using single-molecule imaging of TLR4-MyDDosome signaling in living macrophages, we find that MyDDosomes assemble within minutes of TLR4 stimulation. TLR4/MD2 activation leads only to formation of TLR4/MD2 heterotetramers, but not oligomers, suggesting a stoichiometric mismatch between activated receptors and MyDDosomes. The strength of TLR4 signalling depends not only on the number and size of MyDDosomes formed but also how quickly these structures assemble. Activated TLR4, therefore, acts transiently nucleating assembly of MyDDosomes, a process that is uncoupled from receptor activation. These data explain how the oncogenic mutation of MyD88 (L265P) assembles MyDDosomes in the absence of receptor activation to cause constitutive activation of pro-survival NF-κB signalling. © 2018, Latty et al.

  5. On the influence of surface patterning on tissue self-assembly and mechanics.

    Science.gov (United States)

    Coppola, Valerio; Ventre, Maurizio; Natale, Carlo F; Rescigno, Francesca; Netti, Paolo A

    2018-04-28

    Extracellular matrix assembly and composition influence the biological and mechanical functions of tissues. Developing strategies to control the spatial arrangement of cells and matrix is of central importance for tissue engineering-related approaches relying on self-assembling and scaffoldless processes. Literature reports demonstrated that signals patterned on material surfaces are able to control cell positioning and matrix orientation. However, the mechanisms underlying the interactions between material signals and the structure of the de novo synthesized matrix are far from being thoroughly understood. In this work, we investigated the ordering effect provided by nanoscale topographic patterns on the assembly of tissue sheets grown in vitro. We stimulated MC3T3-E1 preosteoblasts to produce and assemble a collagen-rich matrix on substrates displaying patterns with long- or short-range order. Then, we investigated microstructural features and mechanical properties of the tissue in uniaxial tension. Our results demonstrate that patterned material surfaces are able to control the initial organization of cells in close contact to the surface; then cell-generated contractile forces profoundly remodel tissue structure towards mechanically stable spatial patterns. Such a remodelling effect acts both locally, as it affects cell and nuclear shape and globally, by affecting the gross mechanical response of the tissue. Such an aspect of dynamic interplay between cells and the surrounding matrix must be taken into account when designing material platform for the in vitro generation of tissue with specific microstructural assemblies. Copyright © 2018 John Wiley & Sons, Ltd.

  6. Fluorescent imaging of cancerous tissues for targeted surgery

    Science.gov (United States)

    Bu, Lihong; Shen, Baozhong; Cheng, Zhen

    2014-01-01

    To maximize tumor excision and minimize collateral damage is the primary goal of cancer surgery. Emerging molecular imaging techniques have to “image-guided surgery” developing into “molecular imaging-guided surgery”, which is termed “targeted surgery” in this review. Consequently, the precision of surgery can be advanced from tissue-scale to molecule-scale, enabling “targeted surgery” to be a component of “targeted therapy”. Evidence from numerous experimental and clinical studies has demonstrated significant benefits of fluorescent imaging in targeted surgery with preoperative molecular diagnostic screening. Fluorescent imaging can help to improve intraoperative staging and enable more radical cytoreduction, detect obscure tumor lesions in special organs, highlight tumor margins, better map lymph node metastases, and identify important normal structures intraoperatively. Though limited tissue penetration of fluorescent imaging and tumor heterogeneity are two major hurdles for current targeted surgery, multimodality imaging and multiplex imaging may provide potential solutions to overcome these issues, respectively. Moreover, though many fluorescent imaging techniques and probes have been investigated, targeted surgery remains at a proof-of-principle stage. The impact of fluorescent imaging on cancer surgery will likely be realized through persistent interdisciplinary amalgamation of research in diverse fields. PMID:25064553

  7. A puzzle assembly strategy for fabrication of large engineered cartilage tissue constructs.

    Science.gov (United States)

    Nover, Adam B; Jones, Brian K; Yu, William T; Donovan, Daniel S; Podolnick, Jeremy D; Cook, James L; Ateshian, Gerard A; Hung, Clark T

    2016-03-21

    Engineering of large articular cartilage tissue constructs remains a challenge as tissue growth is limited by nutrient diffusion. Here, a novel strategy is investigated, generating large constructs through the assembly of individually cultured, interlocking, smaller puzzle-shaped subunits. These constructs can be engineered consistently with more desirable mechanical and biochemical properties than larger constructs (~4-fold greater Young׳s modulus). A failure testing technique was developed to evaluate the physiologic functionality of constructs, which were cultured as individual subunits for 28 days, then assembled and cultured for an additional 21-35 days. Assembled puzzle constructs withstood large deformations (40-50% compressive strain) prior to failure. Their ability to withstand physiologic loads may be enhanced by increases in subunit strength and assembled culture time. A nude mouse model was utilized to show biocompatibility and fusion of assembled puzzle pieces in vivo. Overall, the technique offers a novel, effective approach to scaling up engineered tissues and may be combined with other techniques and/or applied to the engineering of other tissues. Future studies will aim to optimize this system in an effort to engineer and integrate robust subunits to fill large defects. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Egr3 dependent sympathetic target tissue innervation in the absence of neuron death.

    Directory of Open Access Journals (Sweden)

    Lin Li

    Full Text Available Nerve Growth Factor (NGF is a target tissue derived neurotrophin required for normal sympathetic neuron survival and target tissue innervation. NGF signaling regulates gene expression in sympathetic neurons, which in turn mediates critical aspects of neuron survival, axon extension and terminal axon branching during sympathetic nervous system (SNS development. Egr3 is a transcription factor regulated by NGF signaling in sympathetic neurons that is essential for normal SNS development. Germline Egr3-deficient mice have physiologic dysautonomia characterized by apoptotic sympathetic neuron death and abnormal innervation to many target tissues. The extent to which sympathetic innervation abnormalities in the absence of Egr3 is caused by altered innervation or by neuron death during development is unknown. Using Bax-deficient mice to abrogate apoptotic sympathetic neuron death in vivo, we show that Egr3 has an essential role in target tissue innervation in the absence of neuron death. Sympathetic target tissue innervation is abnormal in many target tissues in the absence of neuron death, and like NGF, Egr3 also appears to effect target tissue innervation heterogeneously. In some tissues, such as heart, spleen, bowel, kidney, pineal gland and the eye, Egr3 is essential for normal innervation, whereas in other tissues such as lung, stomach, pancreas and liver, Egr3 appears to have little role in innervation. Moreover, in salivary glands and heart, two tissues where Egr3 has an essential role in sympathetic innervation, NGF and NT-3 are expressed normally in the absence of Egr3 indicating that abnormal target tissue innervation is not due to deregulation of these neurotrophins in target tissues. Taken together, these results clearly demonstrate a role for Egr3 in mediating sympathetic target tissue innervation that is independent of neuron survival or neurotrophin deregulation.

  9. Target Assembly to Check Boresight Alignment of Active Sensors

    Science.gov (United States)

    Ramos-Izquierdo, Luis; Scott, V. Stanley; Riris, Haris; Cavanaugh, John; Liiva, Peter; Rodriguez, Michael

    2011-01-01

    A compact and portable target assembly (Fig. 1) has been developed to measure the boresite alignment of LRO's Lunar Orbiter Laser Altimeter (LOLA) instrument at the spacecraft level. The concept for this target assembly has evolved over many years with earlier versions used to test the Mars Observer Laser Altimeter (MOLA), the Geoscience Laser Altimeter System (GLAS), and the Mercury Laser Altimeter (MLA) space-based instruments.

  10. Let's push things forward: disruptive technologies and the mechanics of tissue assembly.

    Science.gov (United States)

    Varner, Victor D; Nelson, Celeste M

    2013-09-01

    Although many of the molecular mechanisms that regulate tissue assembly in the embryo have been delineated, the physical forces that couple these mechanisms to actual changes in tissue form remain unclear. Qualitative studies suggest that mechanical loads play a regulatory role in development, but clear quantitative evidence has been lacking. This is partly owing to the complex nature of these problems - embryonic tissues typically undergo large deformations and exhibit evolving, highly viscoelastic material properties. Still, despite these challenges, new disruptive technologies are enabling study of the mechanics of tissue assembly in unprecedented detail. Here, we present novel experimental techniques that enable the study of each component of these physical problems: kinematics, forces, and constitutive properties. Specifically, we detail advances in light sheet microscopy, optical coherence tomography, traction force microscopy, fluorescence force spectroscopy, microrheology and micropatterning. Taken together, these technologies are helping elucidate a more quantitative understanding of the mechanics of tissue assembly.

  11. Assembly of barcode-like nucleic acid nanostructures.

    Science.gov (United States)

    Wang, Pengfei; Tian, Cheng; Li, Xiang; Mao, Chengde

    2014-10-15

    Barcode-like (BC) nanopatterns from programmed self-assembly of nucleic acids (DNA and RNA) are reported. BC nanostructures are generated by the introduction of open spaces at selected sites to an otherwise closely packed, plain, rectangle nucleic acid nanostructure. This strategy is applied to nanostructures assembled from both origami approach and single stranded tile approach. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Novel drugs targeting Toll-like receptors for antiviral therapy.

    Science.gov (United States)

    Patel, Mira C; Shirey, Kari Ann; Pletneva, Lioubov M; Boukhvalova, Marina S; Garzino-Demo, Alfredo; Vogel, Stefanie N; Blanco, Jorge Cg

    2014-09-01

    Toll-like receptors (TLRs) are sentinel receptors of the host innate immune system that recognize conserved 'pathogen-associated molecular patterns' of invading microbes, including viruses. The activation of TLRs establishes antiviral innate immune responses and coordinates the development of long-lasting adaptive immunity in order to control viral pathogenesis. However, microbe-induced damage to host tissues may release 'danger-associated molecular patterns' that also activate TLRs, leading to an overexuberant inflammatory response and, ultimately, to tissue damage. Thus, TLRs have proven to be promising targets as therapeutics for the treatment of viral infections that result in inflammatory damage or as adjuvants in order to enhance the efficacy of vaccines. Here, we explore recent advances in TLR biology with a focus on novel drugs that target TLRs (agonists and antagonists) for antiviral therapy.

  13. [Self-assembly tissue engineering fibrocartilage model of goat temporomandibular joint disc].

    Science.gov (United States)

    Kang, Hong; Li, Zhen-Qiang; Bi, Yan-Da

    2011-06-01

    To construct self-assembly fibrocartilage model of goat temporomandibular joint disc and observe the biological characteristics of the self-assembled fibrocartilage constructs, further to provide a basis for tissue engineering of the temporomandibular joint disc and other fibrocartilage. Cells from temporomandibular joint discs of goats were harvested and cultured. 5.5 x 10(6) cells were seeded in each agarose well with diameter 5 mm x depth 10 mm, daily replace of medium, cultured for 2 weeks. One day after seeding, goat temporomandibular joint disc cells in agarose wells were gathered and began to self-assemble into a disc-shaped base, then gradually turned into a round shape. When cultured for 2 weeks, hematoxylin-eosin staining was conducted and observed that cells were round and wrapped around by the matrix. Positive Safranin-O/fast green staining for glycosaminoglycans was observed throughout the entire constructs, and picro-sirius red staining was examined and distribution of numerous type I collagen was found. Immunohistochemistry staining demonstrated brown yellow particles in cytoplasm and around extracellular matrix, which showed self-assembly construct can produce type I collagen as native temporomandibular joint disc tissue. Production of extracellular matrix in self-assembly construct as native temporomandibular joint disc tissue indicates that the use of agarose wells to construct engineered temporomandibular joint disc will be possible and practicable.

  14. Biomimetic Layer-by-Layer Self-Assembly of Nanofilms, Nanocoatings, and 3D Scaffolds for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Shichao Zhang

    2018-06-01

    Full Text Available Achieving surface design and control of biomaterial scaffolds with nanometer- or micrometer-scaled functional films is critical to mimic the unique features of native extracellular matrices, which has significant technological implications for tissue engineering including cell-seeded scaffolds, microbioreactors, cell assembly, tissue regeneration, etc. Compared with other techniques available for surface design, layer-by-layer (LbL self-assembly technology has attracted extensive attention because of its integrated features of simplicity, versatility, and nanoscale control. Here we present a brief overview of current state-of-the-art research related to the LbL self-assembly technique and its assembled biomaterials as scaffolds for tissue engineering. An overview of the LbL self-assembly technique, with a focus on issues associated with distinct routes and driving forces of self-assembly, is described briefly. Then, we highlight the controllable fabrication, properties, and applications of LbL self-assembly biomaterials in the forms of multilayer nanofilms, scaffold nanocoatings, and three-dimensional scaffolds to systematically demonstrate advances in LbL self-assembly in the field of tissue engineering. LbL self-assembly not only provides advances for molecular deposition but also opens avenues for the design and development of innovative biomaterials for tissue engineering.

  15. Thin Film Assembly of Spider Silk-like Block Copolymers

    Science.gov (United States)

    2011-01-01

    Shipley, N. H.; Lewis, R. V. Int. J. Biol.Macromol. 1999, 24, 271. (c) Thiel, B. L.; Guess, K. B.; Viney, C. Biopolymers 1997, 41, 703. (13) Silk ...Film Assembly of Spider Silk -like Block Copolymers Sreevidhya T. Krishnaji,†,‡ Wenwen Huang,§ Olena Rabotyagova,†,‡ Eugenia Kharlampieva, ) Ikjun Choi...Received November 26, 2010 We report the self-assembly of monolayers of spider silk -like block copolymers. Langmuir isotherms were obtained for a series of

  16. Magnetic assembly of 3D cell clusters: visualizing the formation of an engineered tissue.

    Science.gov (United States)

    Ghosh, S; Kumar, S R P; Puri, I K; Elankumaran, S

    2016-02-01

    Contactless magnetic assembly of cells into 3D clusters has been proposed as a novel means for 3D tissue culture that eliminates the need for artificial scaffolds. However, thus far its efficacy has only been studied by comparing expression levels of generic proteins. Here, it has been evaluated by visualizing the evolution of cell clusters assembled by magnetic forces, to examine their resemblance to in vivo tissues. Cells were labeled with magnetic nanoparticles, then assembled into 3D clusters using magnetic force. Scanning electron microscopy was used to image intercellular interactions and morphological features of the clusters. When cells were held together by magnetic forces for a single day, they formed intercellular contacts through extracellular fibers. These kept the clusters intact once the magnetic forces were removed, thus serving the primary function of scaffolds. The cells self-organized into constructs consistent with the corresponding tissues in vivo. Epithelial cells formed sheets while fibroblasts formed spheroids and exhibited position-dependent morphological heterogeneity. Cells on the periphery of a cluster were flattened while those within were spheroidal, a well-known characteristic of connective tissues in vivo. Cells assembled by magnetic forces presented visual features representative of their in vivo states but largely absent in monolayers. This established the efficacy of contactless assembly as a means to fabricate in vitro tissue models. © 2016 John Wiley & Sons Ltd.

  17. Lipoproteins in Drosophila melanogaster—Assembly, Function, and Influence on Tissue Lipid Composition

    Science.gov (United States)

    Palm, Wilhelm; Sampaio, Julio L.; Brankatschk, Marko; Carvalho, Maria; Mahmoud, Ali; Shevchenko, Andrej; Eaton, Suzanne

    2012-01-01

    Interorgan lipid transport occurs via lipoproteins, and altered lipoprotein levels correlate with metabolic disease. However, precisely how lipoproteins affect tissue lipid composition has not been comprehensively analyzed. Here, we identify the major lipoproteins of Drosophila melanogaster and use genetics and mass spectrometry to study their assembly, interorgan trafficking, and influence on tissue lipids. The apoB-family lipoprotein Lipophorin (Lpp) is the major hemolymph lipid carrier. It is produced as a phospholipid-rich particle by the fat body, and its secretion requires Microsomal Triglyceride Transfer Protein (MTP). Lpp acquires sterols and most diacylglycerol (DAG) at the gut via Lipid Transfer Particle (LTP), another fat body-derived apoB-family lipoprotein. The gut, like the fat body, is a lipogenic organ, incorporating both de novo–synthesized and dietary fatty acids into DAG for export. We identify distinct requirements for LTP and Lpp-dependent lipid mobilization in contributing to the neutral and polar lipid composition of the brain and wing imaginal disc. These studies define major routes of interorgan lipid transport in Drosophila and uncover surprising tissue-specific differences in lipoprotein lipid utilization. PMID:22844248

  18. From metal-organic squares to porous zeolite-like supramolecular assemblies

    KAUST Repository

    Wang, Shuang; Zhao, Tingting; Li, Guanghua; Wojtas, Łukasz; Huo, Qisheng; Eddaoudi, Mohamed; Liu, Yunling

    2010-01-01

    We report the synthesis, structure, and characterization of two novel porous zeolite-like supramolecular assemblies, ZSA-1 and ZSA-2, having zeolite gis and rho topologies, respectively. The two compounds were assembled from functional metal

  19. Self-assembled peptide-based nanostructures: Smart nanomaterials toward targeted drug delivery.

    Science.gov (United States)

    Habibi, Neda; Kamaly, Nazila; Memic, Adnan; Shafiee, Hadi

    2016-02-01

    Self-assembly of peptides can yield an array of well-defined nanostructures that are highly attractive nanomaterials for many biomedical applications such as drug delivery. Some of the advantages of self-assembled peptide nanostructures over other delivery platforms include their chemical diversity, biocompatibility, high loading capacity for both hydrophobic and hydrophilic drugs, and their ability to target molecular recognition sites. Furthermore, these self-assembled nanostructures could be designed with novel peptide motifs, making them stimuli-responsive and achieving triggered drug delivery at disease sites. The goal of this work is to present a comprehensive review of the most recent studies on self-assembled peptides with a focus on their "smart" activity for formation of targeted and responsive drug-delivery carriers.

  20. Single-Molecule Analysis for RISC Assembly and Target Cleavage.

    Science.gov (United States)

    Sasaki, Hiroshi M; Tadakuma, Hisashi; Tomari, Yukihide

    2018-01-01

    RNA-induced silencing complex (RISC) is a small RNA-protein complex that mediates silencing of complementary target RNAs. Biochemistry has been successfully used to characterize the molecular mechanism of RISC assembly and function for nearly two decades. However, further dissection of intermediate states during the reactions has been warranted to fill in the gaps in our understanding of RNA silencing mechanisms. Single-molecule analysis with total internal reflection fluorescence (TIRF) microscopy is a powerful imaging-based approach to interrogate complex formation and dynamics at the individual molecule level with high sensitivity. Combining this technique with our recently established in vitro reconstitution system of fly Ago2-RISC, we have developed a single-molecule observation system for RISC assembly. In this chapter, we summarize the detailed protocol for single-molecule analysis of chaperone-assisted assembly of fly Ago2-RISC as well as its target cleavage reaction.

  1. Modernization of internal target assembly for AIC-144 cyclotron - proposal

    International Nuclear Information System (INIS)

    Petelenz, B.; Szalkowski, M.

    2007-01-01

    The report describes a prototype of the remotely controlled internal target assembly, designed and built in the Institute of Nuclear Physics. After a series of technical tests, the machine was used in 2006 to produce 73 As from proton bombarded germanium targets. Before this, distribution of the proton beam on the target was checked by autoradiography of irradiated copper foils exposed on large area thermoluminescence detectors. Since the experiments exhibited some severe drawbacks of the machine, the report gives hints how to get rid of them, which is the answer to the question asked by the Deputy Director of the Institute on the topic. The construction parts of the assembly are listed in the Chapter 10. (author)

  2. Direct conversion of injury-site myeloid cells to fibroblast-like cells of granulation tissue.

    Science.gov (United States)

    Sinha, Mithun; Sen, Chandan K; Singh, Kanhaiya; Das, Amitava; Ghatak, Subhadip; Rhea, Brian; Blackstone, Britani; Powell, Heather M; Khanna, Savita; Roy, Sashwati

    2018-03-05

    Inflammation, following injury, induces cellular plasticity as an inherent component of physiological tissue repair. The dominant fate of wound macrophages is unclear and debated. Here we show that two-thirds of all granulation tissue fibroblasts, otherwise known to be of mesenchymal origin, are derived from myeloid cells which are likely to be wound macrophages. Conversion of myeloid to fibroblast-like cells is impaired in diabetic wounds. In cross-talk between keratinocytes and myeloid cells, miR-21 packaged in extracellular vesicles (EV) is required for cell conversion. EV from wound fluid of healing chronic wound patients is rich in miR-21 and causes cell conversion more effectively compared to that by fluid from non-healing patients. Impaired conversion in diabetic wound tissue is rescued by targeted nanoparticle-based delivery of miR-21 to macrophages. This work introduces a paradigm wherein myeloid cells are recognized as a major source of fibroblast-like cells in the granulation tissue.

  3. Scaffold Free Bio-orthogonal Assembly of 3-Dimensional Cardiac Tissue via Cell Surface Engineering

    Science.gov (United States)

    Rogozhnikov, Dmitry; O'Brien, Paul J.; Elahipanah, Sina; Yousaf, Muhammad N.

    2016-12-01

    There has been tremendous interest in constructing in vitro cardiac tissue for a range of fundamental studies of cardiac development and disease and as a commercial system to evaluate therapeutic drug discovery prioritization and toxicity. Although there has been progress towards studying 2-dimensional cardiac function in vitro, there remain challenging obstacles to generate rapid and efficient scaffold-free 3-dimensional multiple cell type co-culture cardiac tissue models. Herein, we develop a programmed rapid self-assembly strategy to induce specific and stable cell-cell contacts among multiple cell types found in heart tissue to generate 3D tissues through cell-surface engineering based on liposome delivery and fusion to display bio-orthogonal functional groups from cell membranes. We generate, for the first time, a scaffold free and stable self assembled 3 cell line co-culture 3D cardiac tissue model by assembling cardiomyocytes, endothelial cells and cardiac fibroblast cells via a rapid inter-cell click ligation process. We compare and analyze the function of the 3D cardiac tissue chips with 2D co-culture monolayers by assessing cardiac specific markers, electromechanical cell coupling, beating rates and evaluating drug toxicity.

  4. Analysis Of Transcriptomes In A Porcine Tissue Collection Using RNA-Seq And Genome Assembly 10

    DEFF Research Database (Denmark)

    Hornshøj, Henrik; Thomsen, Bo; Hedegaard, Jakob

    2011-01-01

    The release of Sus scrofa genome assembly 10 supports improvement of the pig genome annotation and in depth transcriptome analyses using next-generation sequencing technologies. In this study we analyze RNA-seq reads from a tissue collection, including 10 separate tissues from Duroc boars and 10...... short read alignment software we mapped the reads to the genome assembly 10. We extracted contig sequences of gene transcripts using the Cufflinks software. Based on this information we identified expressed genes that are present in the genome assembly. The portion of these genes being previously known...... was roughly estimated by sequence comparison to known genes. Similarly, we searched for genes that are expressed in the tissues but not present in the genome assembly by aligning the non-genome-mapped reads to known gene transcripts. For the genes predicted to have alternative transcript variants by Cufflinks...

  5. Tissue Motion and Assembly During Early Cardiovascular Morphogenesis

    Science.gov (United States)

    Rongish, Brenda

    2010-03-01

    Conventional dogma in the field of cardiovascular developmental biology suggests that cardiac precursor cells migrate to the embryonic midline to form a tubular heart. These progenitors are believed to move relative to their extracellular matrix (ECM); responding to stimulatory and inhibitory cues in their environment. The tubular heart that is formed by 30 hours post fertilization is comprised of two concentric layers: the muscular myocardium and the endothelial-like endocardium, which are separated by a thick layer of ECM believed to be secreted predominantly by the myocardial cells. Here we describe the origin and motility of fluorescently tagged endocardial precursors in transgenic (Tie1-YFP) quail embryos (R. Lansford, Caltech) using epifluorescence time-lapse imaging. To visualize the environment of migrating endocardial progenitors, we labeled two ECM components, fibronectin and fibrillin-2, via in vivo microinjection of fluorochrome-conjugated monoclonal antibodies. Dynamic imaging was performed at stages encompassing tubular heart assembly and early looping. We established the motion of endocardial precursor cells and presumptive cardiac ECM fibrils using both object tracking and particle image velocimetry (image cross correlation). We determined the relative importance of directed cell autonomous motility versus passive tissue movements in endocardial morphogenesis. The data show presumptive endocardial cells and cardiac ECM fibrils are swept passively into the anterior and posterior poles of the elongating tubular heart. These quantitative data indicate the contribution of cell autonomous motility displayed by endocardial precursors is limited. Thus, tissue motion drives most of the cell displacements during endocardial morphogenesis.

  6. In-situ crosslinkable and self-assembling elastin-like polypeptide block copolymers for cartilage tissue repair

    Science.gov (United States)

    Lim, Dong Woo

    This work describes the development of genetically engineered elastin-like polypeptide (ELP) block copolymers as in-situ gelling scaffolds for cartilage tissue repair. The central hypothesis underlying this work is that ELP based biopolymers can be exploited as injectable biomaterials by rapid chemical crosslinking. To prove this, gene libraries encoding ELP having different molecular weights and amino acid sequences, and ELP block copolymers composed of various ELP blocks having diverse amino acid composition, length, and phase transition behavior were synthesized by recursive directional ligation, expressed in E. Coli and purified by inverse transition cycling. Mannich-type condensation of hydroxymethylphosphines (HMPs) with primary- and secondary-amines of amino acids was developed as a new crosslinking method of polypeptides. Chemically crosslinked ELP hydrogels were formed rapidly in an aqueous solution by reaction of ELPs containing periodic lysine residues with HMPs. The crosslinking density and mechanical property of the ELP hydrogels were controlled at the sequence level by varying the Lys density in ELPs composed of mono-block as well as by segregation of the Lys residues within specific blocks of tri-block architectures. Fibroblasts embedded in ELP hydrogels survived the crosslinking process and were viable after in vitro culture for at least 3 days. The DNA content of fibroblasts within the tri-block gels was significantly higher than that in the mono-block gels at day 3. These results suggest that the HMP crosslinked ELP block copolymer hydrogels show finely tuned mechanical properties and different microenvironments for cell viability as well as potential as in-situ crosslinkable biopolymers for tissue repair applications with load-bearing environments. As an alternative, rheological behavior of the ELP block copolymers and ELP-grafted hyaluronic acids (HAs) as artificial extracellular matrices (ECMs) showed that they were thermally aggregated into

  7. Pericyte-targeting drug delivery and tissue engineering

    Directory of Open Access Journals (Sweden)

    Kang E

    2016-05-01

    Full Text Available Eunah Kang,1 Jong Wook Shin2 1School of Chemical Engineering and Material Science, 2Division of Allergic and Pulmonary Medicine, Department of Internal Medicine, College of Medicine, Chung-Ang University, Dongjak-Gu, Seoul, South Korea Abstract: Pericytes are contractile mural cells that wrap around the endothelial cells of capillaries and venules. Depending on the triggers by cellular signals, pericytes have specific functionality in tumor microenvironments, properties of potent stem cells, and plasticity in cellular pathology. These features of pericytes can be activated for the promotion or reduction of angiogenesis. Frontier studies have exploited pericyte-targeting drug delivery, using pericyte-specific peptides, small molecules, and DNA in tumor therapy. Moreover, the communication between pericytes and endothelial cells has been applied to the induction of vessel neoformation in tissue engineering. Pericytes may prove to be a novel target for tumor therapy and tissue engineering. The present paper specifically reviews pericyte-specific drug delivery and tissue engineering, allowing insight into the emerging research targeting pericytes. Keywords: pericytes, pericyte-targeting drug delivery, tissue engineering, platelet-derived growth factor, angiogenesis, vascular remodeling

  8. Micellar Self-Assembly of Recombinant Resilin-/Elastin-Like Block Copolypeptides.

    Science.gov (United States)

    Weitzhandler, Isaac; Dzuricky, Michael; Hoffmann, Ingo; Garcia Quiroz, Felipe; Gradzielski, Michael; Chilkoti, Ashutosh

    2017-08-14

    Reported here is the synthesis of perfectly sequence defined, monodisperse diblock copolypeptides of hydrophilic elastin-like and hydrophobic resilin-like polypeptide blocks and characterization of their self-assembly as a function of structural parameters by light scattering, cryo-TEM, and small-angle neutron scattering. A subset of these diblock copolypeptides exhibit lower critical solution temperature and upper critical solution temperature phase behavior and self-assemble into spherical or cylindrical micelles. Their morphologies are dictated by their chain length, degree of hydrophilicity, and hydrophilic weight fraction of the ELP block. We find that (1) independent of the length of the corona-forming ELP block there is a minimum threshold in the length of the RLP block below which self-assembly does not occur, but that once that threshold is crossed, (2) the RLP block length is a unique molecular parameter to independently tune self-assembly and (3) increasing the hydrophobicity of the corona-forming ELP drives a transition from spherical to cylindrical morphology. Unlike the self-assembly of purely ELP-based block copolymers, the self-assembly of RLP-ELPs can be understood by simple principles of polymer physics relating hydrophilic weight fraction and polymer-polymer and polymer-solvent interactions to micellar morphology, which is important as it provides a route for the de novo design of desired nanoscale morphologies from first principles.

  9. Modular assembly of transposable element arrays by microsatellite targeting in the guayule and rice genomes.

    Science.gov (United States)

    Valdes Franco, José A; Wang, Yi; Huo, Naxin; Ponciano, Grisel; Colvin, Howard A; McMahan, Colleen M; Gu, Yong Q; Belknap, William R

    2018-04-19

    Guayule (Parthenium argentatum A. Gray) is a rubber-producing desert shrub native to Mexico and the United States. Guayule represents an alternative to Hevea brasiliensis as a source for commercial natural rubber. The efficient application of modern molecular/genetic tools to guayule improvement requires characterization of its genome. The 1.6 Gb guayule genome was sequenced, assembled and annotated. The final 1.5 Gb assembly, while fragmented (N 50  = 22 kb), maps > 95% of the shotgun reads and is essentially complete. Approximately 40,000 transcribed, protein encoding genes were annotated on the assembly. Further characterization of this genome revealed 15 families of small, microsatellite-associated, transposable elements (TEs) with unexpected chromosomal distribution profiles. These SaTar (Satellite Targeted) elements, which are non-autonomous Mu-like elements (MULEs), were frequently observed in multimeric linear arrays of unrelated individual elements within which no individual element is interrupted by another. This uniformly non-nested TE multimer architecture has not been previously described in either eukaryotic or prokaryotic genomes. Five families of similarly distributed non-autonomous MULEs (microsatellite associated, modularly assembled) were characterized in the rice genome. Families of TEs with similar structures and distribution profiles were identified in sorghum and citrus. The sequencing and assembly of the guayule genome provides a foundation for application of current crop improvement technologies to this plant. In addition, characterization of this genome revealed SaTar elements with distribution profiles unique among TEs. Satar targeting appears based on an alternative MULE recombination mechanism with the potential to impact gene evolution.

  10. Self-assembled silk sericin/poloxamer nanoparticles as nanocarriers of hydrophobic and hydrophilic drugs for targeted delivery

    International Nuclear Information System (INIS)

    Mandal, Biman B; Kundu, S C

    2009-01-01

    In recent times self-assembled micellar nanoparticles have been successfully employed in tissue engineering for targeted drug delivery applications. In this review, silk sericin protein from non-mulberry Antheraea mylitta tropical tasar silk cocoons was blended with pluronic F-127 and F-87 in the presence of solvents to achieve self-assembled micellar nanostructures capable of carrying both hydrophilic (FITC-inulin) and hydrophobic (anticancer drug paclitaxel) drugs. The fabricated nanoparticles were subsequently characterized for their size distribution, drug loading capability, cellular uptake and cytotoxicity. Nanoparticle sizes ranged between 100 and 110 nm in diameter as confirmed by dynamic light scattering. Rapid uptake of these particles into cells was observed in in vitro cellular uptake studies using breast cancer MCF-7 cells. In vitro cytotoxicity assay using paclitaxel-loaded nanoparticles against breast cancer cells showed promising results comparable to free paclitaxel drugs. Drug-encapsulated nanoparticle-induced apoptosis in MCF-7 cells was confirmed by FACS and confocal microscopic studies using Annexin V staining. Up-regulation of pro-apoptotic protein Bax, down-regulation of anti-apoptotic protein Bcl-2 and cleavage of regulatory protein PARP through Western blot analysis suggested further drug-induced apoptosis in cells. This study projects silk sericin protein as an alternative natural biomaterial for fabrication of self-assembled nanoparticles in the presence of poloxamer for successful delivery of both hydrophobic and hydrophilic drugs to target sites.

  11. Self-assembled silk sericin/poloxamer nanoparticles as nanocarriers of hydrophobic and hydrophilic drugs for targeted delivery

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Biman B; Kundu, S C, E-mail: kundu@hijli.iitkgp.ernet.i [Department of Biotechnology, Indian Institute of Technology, Kharagpur 721302 (India)

    2009-09-02

    In recent times self-assembled micellar nanoparticles have been successfully employed in tissue engineering for targeted drug delivery applications. In this review, silk sericin protein from non-mulberry Antheraea mylitta tropical tasar silk cocoons was blended with pluronic F-127 and F-87 in the presence of solvents to achieve self-assembled micellar nanostructures capable of carrying both hydrophilic (FITC-inulin) and hydrophobic (anticancer drug paclitaxel) drugs. The fabricated nanoparticles were subsequently characterized for their size distribution, drug loading capability, cellular uptake and cytotoxicity. Nanoparticle sizes ranged between 100 and 110 nm in diameter as confirmed by dynamic light scattering. Rapid uptake of these particles into cells was observed in in vitro cellular uptake studies using breast cancer MCF-7 cells. In vitro cytotoxicity assay using paclitaxel-loaded nanoparticles against breast cancer cells showed promising results comparable to free paclitaxel drugs. Drug-encapsulated nanoparticle-induced apoptosis in MCF-7 cells was confirmed by FACS and confocal microscopic studies using Annexin V staining. Up-regulation of pro-apoptotic protein Bax, down-regulation of anti-apoptotic protein Bcl-2 and cleavage of regulatory protein PARP through Western blot analysis suggested further drug-induced apoptosis in cells. This study projects silk sericin protein as an alternative natural biomaterial for fabrication of self-assembled nanoparticles in the presence of poloxamer for successful delivery of both hydrophobic and hydrophilic drugs to target sites.

  12. Design of the MYRRHA Spallation Target Assembly

    International Nuclear Information System (INIS)

    Keijers, S.; Fernandez, R.; Stankovskiy, A.; Kennedy, G.; Van Tichelen, K.

    2015-01-01

    MYRRHA (Multi-purpose hybrid Research Reactor for High-tech Applications) is a multi-purpose research facility currently being developed at SCK.CEN. MYRRHA is based on the ADS (Accelerator Driven System) concept where a proton accelerator, a spallation target and a subcritical reactor are coupled. MYRRHA will demonstrate the ADS full concept by coupling these three components at a reasonable power level. As a flexible irradiation facility, the MYRRHA research reactor will be able to work in both critical and subcritical modes. In this way, MYRRHA will allow fuel developments for innovative reactor systems, material research for GEN IV and fusion reactors, and radioisotope production for medical and industrial applications. MYRRHA will be cooled by Lead Bismuth Eutectic (LBE) and will play an important role in the development of the Pb-alloys technology needed for the LFR (Lead Fast Reactor) GEN IV concept. This paper describes the evolution of the MYRRHA spallation target design. In the early phase of the MYRRHA project (XT-ADS), the target design was based on a dedicated spallation loop inside the primary reactor vessel. Within the core, the 3 central fuel assembly positions were occupied by the spallation target, which enabled a windowless design created by a free surface of LBE facing the proton beam. The windowless option was preferred because of high heat loads in combination with severe irradiation damage in the target region would result in unacceptably short lifetimes of a target window. The LBE in the loop served as spallation target and as target coolant, but was separated from the LBE cooling the reactor core. The loop was equipped with its own pump, heat exchanger and conditioning system. The change from cyclotron to linear accelerator allowed the increase in proton energy from 350 MeV to 600 MeV. This modification led to an important reduction of the specific heat load at the target level and an improvement of the neutronic performance. In addition to

  13. Seismic analysis of fuel and target assemblies at a production reactor

    International Nuclear Information System (INIS)

    Braverman, J.I.; Wang, Y.K.

    1991-01-01

    This paper describes the unique modeling and analysis considerations used to assess the seismic adequacy of the fuel and target assemblies in a production reactor at Savannah River Site. This confirmatory analysis was necessary to provide assurance that the reactor can operate safely during a seismic event and be brought to a safe shutdown condition. The plant which was originally designed in the 1950's required to be assessed to more current seismic criteria. The design of the reactor internals and the magnitude of the structural responses enabled the use of a linear elastic dynamic analysis. A seismic analysis was performed using a finite element model consisting of the fuel and target assemblies, reactor tank, and a portion of the concrete structure supporting the reactor tank. The effects of submergence of the fuel and target assemblies in the water contained within the reactor tank can have a significant effect on their seismic response. Thus, the model included hydrodynamic fluid coupling effects between the assemblies and the reactor tank. Fluid coupling mass terms were based on formulations for solid bodies immersed in incompressible and frictionless fluids. The potential effects of gap conditions were also assessed in this evaluation. 5 refs., 6 figs., 1 tab

  14. Tissue-Mimicking Geometrical Constraints Stimulate Tissue-Like Constitution and Activity of Mouse Neonatal and Human-Induced Pluripotent Stem Cell-Derived Cardiac Myocytes

    Directory of Open Access Journals (Sweden)

    Götz Pilarczyk

    2016-01-01

    Full Text Available The present work addresses the question of to what extent a geometrical support acts as a physiological determining template in the setup of artificial cardiac tissue. Surface patterns with alternating concave to convex transitions of cell size dimensions were used to organize and orientate human-induced pluripotent stem cell (hIPSC-derived cardiac myocytes and mouse neonatal cardiac myocytes. The shape of the cells, as well as the organization of the contractile apparatus recapitulates the anisotropic line pattern geometry being derived from tissue geometry motives. The intracellular organization of the contractile apparatus and the cell coupling via gap junctions of cell assemblies growing in a random or organized pattern were examined. Cell spatial and temporal coordinated excitation and contraction has been compared on plain and patterned substrates. While the α-actinin cytoskeletal organization is comparable to terminally-developed native ventricular tissue, connexin-43 expression does not recapitulate gap junction distribution of heart muscle tissue. However, coordinated contractions could be observed. The results of tissue-like cell ensemble organization open new insights into geometry-dependent cell organization, the cultivation of artificial heart tissue from stem cells and the anisotropy-dependent activity of therapeutic compounds.

  15. From metal-organic squares to porous zeolite-like supramolecular assemblies

    KAUST Repository

    Wang, Shuang

    2010-12-29

    We report the synthesis, structure, and characterization of two novel porous zeolite-like supramolecular assemblies, ZSA-1 and ZSA-2, having zeolite gis and rho topologies, respectively. The two compounds were assembled from functional metal-organic squares (MOSs) via directional hydrogen-bonding interactions and exhibited permanent microporosity and thermal stability up to 300 °C. © 2010 American Chemical Society.

  16. MiR-32 promotes gastric carcinoma tumorigenesis by targeting Kruppel-like factor 4

    Energy Technology Data Exchange (ETDEWEB)

    Yan, Chao [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China); Yu, Jianchun, E-mail: yu_jchpumch@163.com [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China); Liu, Yuqin [Cell Culture Center, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences and Peking Union Medical College, Beijing, 100005 (China); Kang, Weiming; Ma, Zhiqiang; Zhou, Li [Department of General Surgery, Peking Union Medical College Hospital, Chinese Academy of Medical Science and Peking Union Medical College, Beijing, 100730 (China)

    2015-11-27

    Gastric cancer (GC) is a prevalent malignant cancer worldwide and is highly lethal because of its fast growth. Currently, the clinical therapy options for GC remain limited. MiR-32 has been reported as an oncogenic microRNA in many cancers, but its role in GC is unclear. Here, we found that miR-32 was overexpressed in GC tissues compared with adjacent normal tissue, and miR-32 was higher in GC patients' plasma compared with healthy individuals. Furthermore, we have identified miR-32 to be oncogenic, by promoting gastric cell proliferation, migration and invasion. We also identified Kruppel-like factor 4 (KLF4) as a direct target of miR-32. Knockdown of KLF4 promoted proliferation, migration and invasion of GC cells. We conclude that miR-32 promotes GC cell proliferation, migration and invasion by targeting KLF4, suggesting that the miR-32-KLF4 pathway may be useful in clinical diagnosis and therapeutics. - Highlights: • miR-32 was overexpression in GC tissues than adjacent normal tissue. • miR-32 was higher in GC patients' plasma compared with healthy people. • miR-32 promotes GC cell proliferation, migration and invasion by targeting KLF4.

  17. Self-assembling complexes of quantum dots and scFv antibodies for cancer cell targeting and imaging.

    Directory of Open Access Journals (Sweden)

    Tatiana A Zdobnova

    Full Text Available Semiconductor quantum dots represent a novel class of fluorophores with unique physical and chemical properties which could enable a remarkable broadening of the current applications of fluorescent imaging and optical diagnostics. Complexes of quantum dots and antibodies are promising visualising agents for fluorescent detection of selective biomarkers overexpressed in tumor tissues. Here we describe the construction of self-assembling fluorescent complexes of quantum dots and anti-HER1 or anti-HER2/neu scFv antibodies and their interactions with cultured tumor cells. A binding strategy based on a very specific non-covalent interaction between two proteins, barnase and barstar, was used to connect quantum dots and the targeting antibodies. Such a strategy allows combining the targeting and visualization functions simply by varying the corresponding modules of the fluorescent complex.

  18. Opal-like Multicolor Appearance of Self-Assembled Photonic Array.

    Science.gov (United States)

    Arnon, Zohar A; Pinotsi, Dorothea; Schmidt, Matthias; Gilead, Sharon; Guterman, Tom; Sadhanala, Aditya; Ahmad, Shahab; Levin, Aviad; Walther, Paul; Kaminski, Clemens F; Fändrich, Marcus; Kaminski Schierle, Gabriele S; Adler-Abramovich, Lihi; Shimon, Linda J W; Gazit, Ehud

    2018-06-20

    Molecular self-assembly of short peptide building blocks leads to the formation of various material architectures that may possess unique physical properties. Recent studies had confirmed the key role of biaromaticity in peptide self-assembly, with the diphenylalanine (FF) structural family as an archetypal model. Another significant direction in the molecular engineering of peptide building blocks is the use of fluorenylmethoxycarbonyl (Fmoc) modification, which promotes the assembly process and may result in nanostructures with distinctive features and macroscopic hydrogel with supramolecular features and nanoscale order. Here, we explored the self-assembly of the protected, noncoded fluorenylmethoxycarbonyl-β,β-diphenyl-Ala-OH (Fmoc-Dip) amino acid. This process results in the formation of elongated needle-like crystals with notable aromatic continuity. By altering the assembly conditions, arrays of spherical particles were formed that exhibit strong light scattering. These arrays display vivid coloration, strongly resembling the appearance of opal gemstones. However, unlike the Rayleigh scattering effect produced by the arrangement of opal, the described optical phenomenon is attributed to Mie scattering. Moreover, by controlling the solution evaporation rate, i.e., the assembly kinetics, we were able to manipulate the resulting coloration. This work demonstrates a bottom-up approach, utilizing self-assembly of a protected amino acid minimal building block, to create arrays of organic, light-scattering colorful surfaces.

  19. A new construction technique for tissue-engineered heart valves using the self-assembly method.

    Science.gov (United States)

    Tremblay, Catherine; Ruel, Jean; Bourget, Jean-Michel; Laterreur, Véronique; Vallières, Karine; Tondreau, Maxime Y; Lacroix, Dan; Germain, Lucie; Auger, François A

    2014-11-01

    Tissue engineering appears as a promising option to create new heart valve substitutes able to overcome the serious drawbacks encountered with mechanical substitutes or tissue valves. The objective of this article is to present the construction method of a new entirely biological stentless aortic valve using the self-assembly method and also a first assessment of its behavior in a bioreactor when exposed to a pulsatile flow. A thick tissue was created by stacking several fibroblast sheets produced with the self-assembly technique. Different sets of custom-made templates were designed to confer to the thick tissue a three-dimensional (3D) shape similar to that of a native aortic valve. The construction of the valve was divided in two sequential steps. The first step was the installation of the thick tissue in a flat preshaping template followed by a 4-week maturation period. The second step was the actual cylindrical 3D forming of the valve. The microscopic tissue structure was assessed using histological cross sections stained with Masson's Trichrome and Picrosirius Red. The thick tissue remained uniformly populated with cells throughout the construction steps and the dense extracellular matrix presented corrugated fibers of collagen. This first prototype of tissue-engineered heart valve was installed in a bioreactor to assess its capacity to sustain a light pulsatile flow at a frequency of 0.5 Hz. Under the light pulsed flow, it was observed that the leaflets opened and closed according to the flow variations. This study demonstrates that the self-assembly method is a viable option for the construction of complex 3D shapes, such as heart valves, with an entirely biological material.

  20. The rapid manufacture of uniform composite multicellular-biomaterial micropellets, their assembly into macroscopic organized tissues, and potential applications in cartilage tissue engineering.

    Science.gov (United States)

    Babur, Betul Kul; Kabiri, Mahboubeh; Klein, Travis Jacob; Lott, William B; Doran, Michael Robert

    2015-01-01

    We and others have published on the rapid manufacture of micropellet tissues, typically formed from 100-500 cells each. The micropellet geometry enhances cellular biological properties, and in many cases the micropellets can subsequently be utilized as building blocks to assemble complex macrotissues. Generally, micropellets are formed from cells alone, however when replicating matrix-rich tissues such as cartilage it would be ideal if matrix or biomaterials supplements could be incorporated directly into the micropellet during the manufacturing process. Herein we describe a method to efficiently incorporate donor cartilage matrix into tissue engineered cartilage micropellets. We lyophilized bovine cartilage matrix, and then shattered it into microscopic pieces having average dimensions manufacture of thousands of replica composite micropellets, with each micropellet having a material/CD core and a cellular surface. This micropellet organization enabled the rapid bulking up of the micropellet core matrix content, and left an adhesive cellular outer surface. This morphological organization enabled the ready assembly of the composite micropellets into macroscopic tissues. Generically, this is a versatile method that enables the rapid and uniform integration of biomaterials into multicellular micropellets that can then be used as tissue building blocks. In this study, the addition of CD resulted in an approximate 8-fold volume increase in the micropellets, with the donor matrix functioning to contribute to an increase in total cartilage matrix content. Composite micropellets were readily assembled into macroscopic cartilage tissues; the incorporation of CD enhanced tissue size and matrix content, but did not enhance chondrogenic gene expression.

  1. Self assembled temperature responsive surfaces for generation of cell patches for bone tissue engineering

    International Nuclear Information System (INIS)

    Valmikinathan, Chandra M; ChangWei; Xu Jiahua; Yu Xiaojun

    2012-01-01

    One of the major challenges in the fabrication of tissue engineered scaffolds is the ability of the scaffold to biologically mimic autograft-like tissues. One of the alternate approaches to achieve this is by the application of cell seeded scaffolds with optimal porosity and mechanical properties. However, the current approaches for seeding cells on scaffolds are not optimal in terms of seeding efficiencies, cell penetration into the scaffold and more importantly uniform distribution of cells on the scaffold. Also, recent developments in scaffold geometries to enhance surface areas, pore sizes and porosities tend to further complicate the scenario. Cell sheet-based approaches for cell seeding have demonstrated a successful approach to generate scaffold-free tissue engineering approaches. However, the method of generating the temperature responsive surface is quite challenging and requires carcinogenic reagents and gamma rays. Therefore, here, we have developed temperature responsive substrates by layer-by-layer self assembly of smart polymers. Multilayer thin films prepared from tannic acid and poly N-isopropylacrylamide were fabricated based on their electrostatic and hydrogen bonding interactions. Cell attachment and proliferation studies on these thin films showed uniform cell attachment on the substrate, matching tissue culture plates. Also, the cells could be harvested as cell patches and sheets from the scaffolds, by reducing the temperature for a short period of time, and seeded onto porous scaffolds for tissue engineering applications. An enhanced cell seeding efficiency on scaffolds was observed using the cell patch-based technique as compared to seeding cells in suspension. Owing to the already pre-existent cell–cell and cell–extracellular matrix interactions, the cell patch showed the ability to reattach rapidly onto scaffolds and showed enhanced ability to proliferate and differentiate into a bone-like matrix. (paper)

  2. Viral capsid assembly as a model for protein aggregation diseases: Active processes catalyzed by cellular assembly machines comprising novel drug targets.

    Science.gov (United States)

    Marreiros, Rita; Müller-Schiffmann, Andreas; Bader, Verian; Selvarajah, Suganya; Dey, Debendranath; Lingappa, Vishwanath R; Korth, Carsten

    2015-09-02

    Viruses can be conceptualized as self-replicating multiprotein assemblies, containing coding nucleic acids. Viruses have evolved to exploit host cellular components including enzymes to ensure their replicative life cycle. New findings indicate that also viral capsid proteins recruit host factors to accelerate their assembly. These assembly machines are RNA-containing multiprotein complexes whose composition is governed by allosteric sites. In the event of viral infection, the assembly machines are recruited to support the virus over the host and are modified to achieve that goal. Stress granules and processing bodies may represent collections of such assembly machines, readily visible by microscopy but biochemically labile and difficult to isolate by fractionation. We hypothesize that the assembly of protein multimers such as encountered in neurodegenerative or other protein conformational diseases, is also catalyzed by assembly machines. In the case of viral infection, the assembly machines have been modified by the virus to meet the virus' need for rapid capsid assembly rather than host homeostasis. In the case of the neurodegenerative diseases, it is the monomers and/or low n oligomers of the so-called aggregated proteins that are substrates of assembly machines. Examples for substrates are amyloid β peptide (Aβ) and tau in Alzheimer's disease, α-synuclein in Parkinson's disease, prions in the prion diseases, Disrupted-in-schizophrenia 1 (DISC1) in subsets of chronic mental illnesses, and others. A likely continuum between virus capsid assembly and cell-to-cell transmissibility of aggregated proteins is remarkable. Protein aggregation diseases may represent dysfunction and dysregulation of these assembly machines analogous to the aberrations induced by viral infection in which cellular homeostasis is pathologically reprogrammed. In this view, as for viral infection, reset of assembly machines to normal homeostasis should be the goal of protein aggregation

  3. A molecular assembly system for presentation of antigens on the surface of HBc virus-like particles

    International Nuclear Information System (INIS)

    Blokhina, Elena A.; Kuprianov, Victor V.; Stepanova, Ludmila A.; Tsybalova, Ludmila M.; Kiselev, Oleg I.; Ravin, Nikolai V.; Skryabin, Konstantin G.

    2013-01-01

    Hepatitis B virus-like particles, icosahedral structures formed by multiple core protein dimers, are promising immune-enhancing vaccine carriers for foreign antigens. Insertions into the surface-exposed immunodominant loop are especially immunogenic. However, the need to conserve the particulate structure to ensure high immunogenicity imposes restraints on the nature of the heterologous sequence that can be inserted. We propose a new approach to constructing HBc particles linked to the target epitopes that relies on non-covalent interactions between the epitope and pre-assembled unmodified HBc particles. Interaction was enabled by fusion of the epitope to the GSLLGRMKGA peptide, binding to the spike tips. This peptide may be used as a “binding tag” allowing in vitro construction of HBc particles carrying the target peptide. Such virus-like particles carrying multiple copies of the extracellular domain of the M2 protein of different influenza strains appeared to be highly immunogenic and protected immunised mice against a lethal influenza challenge.

  4. A molecular assembly system for presentation of antigens on the surface of HBc virus-like particles

    Energy Technology Data Exchange (ETDEWEB)

    Blokhina, Elena A.; Kuprianov, Victor V. [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); Stepanova, Ludmila A.; Tsybalova, Ludmila M. [Research Institute of Influenza, Russian Federation Ministry of Health and Social Development, St. Petersburg (Russian Federation); Kiselev, Oleg I. [Research Institute of Influenza, Russian Federation Ministry of Health and Social Development, St. Petersburg (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation); Ravin, Nikolai V., E-mail: nravin@biengi.ac.ru [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation); Skryabin, Konstantin G. [Centre ' Bioengineering' , Russian Academy of Sciences, 117312 Prosp. 60-letya Oktyabrya 7-1, Moscow (Russian Federation); GenNanotech Ltd, St. Petersburg (Russian Federation)

    2013-01-20

    Hepatitis B virus-like particles, icosahedral structures formed by multiple core protein dimers, are promising immune-enhancing vaccine carriers for foreign antigens. Insertions into the surface-exposed immunodominant loop are especially immunogenic. However, the need to conserve the particulate structure to ensure high immunogenicity imposes restraints on the nature of the heterologous sequence that can be inserted. We propose a new approach to constructing HBc particles linked to the target epitopes that relies on non-covalent interactions between the epitope and pre-assembled unmodified HBc particles. Interaction was enabled by fusion of the epitope to the GSLLGRMKGA peptide, binding to the spike tips. This peptide may be used as a 'binding tag' allowing in vitro construction of HBc particles carrying the target peptide. Such virus-like particles carrying multiple copies of the extracellular domain of the M2 protein of different influenza strains appeared to be highly immunogenic and protected immunised mice against a lethal influenza challenge.

  5. Diversity, assembly and regulation of archaeal type IV pili-like and non-type-IV pili-like surface structures.

    Science.gov (United States)

    Lassak, Kerstin; Ghosh, Abhrajyoti; Albers, Sonja-Verena

    2012-01-01

    Archaea have evolved fascinating surface structures allowing rapid adaptation to changing environments. The archaeal surface appendages display such diverse biological roles as motility, adhesion, biofilm formation, exchange of genetic material and species-specific interactions and, in turn, increase fitness of the cells. Intriguingly, despite sharing the same functions with their bacterial counterparts, the assembly mechanism of many archaeal surface structures is rather related to assembly of bacterial type IV pili. This review summarizes our state-of-the-art knowledge about unique structural and biochemical properties of archaeal surface appendages with a particular focus on archaeal type IV pili-like structures. The latter comprise not only widely distributed archaella (formerly known as archaeal flagella), but also different highly specialized archaeal pili, which are often restricted to certain species. Recent findings regarding assembly mechanisms, structural aspects and physiological roles of these type IV pili-like structures will be discussed in detail. Recently, first regulatory proteins involved in transition from both planktonic to sessile lifestyle and in assembly of archaella were identified. To conclude, we provide novel insights into regulatory mechanisms underlying the assembly of archaeal surface structures. Copyright © 2012. Published by Elsevier Masson SAS.

  6. Three-Dimensional Human Bronchial-Tracheal Epithelial Tissue-Like Assemblies (TLAs) as Hosts for Severe Acute Respiratory Syndrome (SARS)-CoV Infection

    Science.gov (United States)

    Suderman, M. T.; McCarthy, M.; Mossell, E.; Watts, D. M.; Peters, C. J.; Shope, R.; Goodwin, T. J.

    2006-01-01

    A three-dimensional (3-D) tissue-like assembly (TLA) of human bronchial-tracheal mesenchymal (HBTC) cells with an overlay of human bronchial epithelial (BEAS-2B) cells was constructed using a NASA Bioreactor to survey the infectivity of SARS-CoV. This TLA was inoculated with a low passage number Urbani strain of SARS-CoV. At selected intervals over a 10-day period, media and cell aliquots of the 3-D TLA were harvested for viral titer assay and for light and electron microscopy examination. All viral titer assays were negative in both BEAS-2B two-dimensional monolayer and TLA. Light microscopy immunohistochemistry demonstrated antigen-antibody reactivity with anti-SARS-CoV polyclonal antibody to spike and nuclear proteins on cell membranes and cytoplasm. Coronavirus Group 2 cross-reactivity was demonstrated by positive reaction to anti-FIPV 1 and anti-FIPV 1 and 2 antibodies. TLA examination by transmission electron microscopy indicated increasing cytoplasmic vacuolation with numerous electron-dense bodies measuring 45 to 270 nm from days 4 through 10. There was no evidence of membrane blebbing, membrane duplication, or fragmentation of organelles in the TLAs. However, progressive disruption of endoplasmic reticulum was observed throughout the cells. Antibody response to SARS-CoV specific spike and nucleocapsid glycoproteins, cross-reactivity with FIPV antibodies, and the cytoplasmic pathology suggests this HBTE TLA model is permissive to SARS-CoV infection.

  7. Self-assembly of virus-like particles of canine parvovirus capsid protein expressed from Escherichia coli and application as virus-like particle vaccine.

    Science.gov (United States)

    Xu, Jin; Guo, Hui-Chen; Wei, Yan-Quan; Dong, Hu; Han, Shi-Chong; Ao, Da; Sun, De-Hui; Wang, Hai-Ming; Cao, Sui-Zhong; Sun, Shi-Qi

    2014-04-01

    Canine parvovirus disease is an acute infectious disease caused by canine parvovirus (CPV). Current commercial vaccines are mainly attenuated and inactivated; as such, problems concerning safety may occur. To resolve this problem, researchers developed virus-like particles (VLPs) as biological nanoparticles resembling natural virions and showing high bio-safety. This property allows the use of VLPs for vaccine development and mechanism studies of viral infections. Tissue-specific drug delivery also employs VLPs as biological nanomaterials. Therefore, VLPs derived from CPV have a great potential in medicine and diagnostics. In this study, small ubiquitin-like modifier (SUMO) fusion motif was utilized to express a whole, naturalVP2 protein of CPV in Escherichia coli. After the cleavage of the fusion motif, the CPV VP2 protein has self-assembled into VLPs. The VLPs had a size and shape that resembled the authentic virus capsid. However, the self-assembly efficiency of VLPs can be affected by different pH levels and ionic strengths. The mice vaccinated subcutaneously with CPV VLPs and CPV-specific immune responses were compared with those immunized with the natural virus. This result showed that VLPs can effectively induce anti-CPV specific antibody and lymphocyte proliferation as a whole virus. This result further suggested that the antigen epitope of CPV was correctly present on VLPs, thereby showing the potential application of a VLP-based CPV vaccine.

  8. Quantitative frequency-domain fluorescence spectroscopy in tissues and tissue-like media

    Science.gov (United States)

    Cerussi, Albert Edward

    1999-09-01

    In the never-ending quest for improved medical technology at lower cost, modern near-infrared optical spectroscopy offers the possibility of inexpensive technology for quantitative and non-invasive diagnoses. Hemoglobin is the dominant chromophore in the 700-900 nm spectral region and as such it allows for the optical assessment of hemoglobin concentration and tissue oxygenation by absorption spectroscopy. However, there are many other important physiologically relevant compounds or physiological states that cannot be effectively sensed via optical methods because of poor optical contrast. In such cases, contrast enhancements are required. Fluorescence spectroscopy is an attractive component of optical tissue spectroscopy. Exogenous fluorophores, as well as some endogenous ones, may furnish the desperately needed sensitivity and specificity that is lacking in near-infrared optical tissue spectroscopy. The main focus of this thesis was to investigate the generation and propagation of fluorescence photons inside tissues and tissue-like media (i.e., scattering dominated media). The standard concepts of fluorescence spectroscopy have been incorporated into a diffusion-based picture that is sometimes referred to as photon migration. The novelty of this work lies in the successful quantitative recovery of fluorescence lifetimes, absolute fluorescence quantum yields, fluorophore concentrations, emission spectra, and both scattering and absorption coefficients at the emission wavelength from a tissue-like medium. All of these parameters are sensitive to the fluorophore local environment and hence are indicators of the tissue's physiological state. One application demonstrating the capabilities of frequency-domain lifetime spectroscopy in tissue-like media is a study of the binding of ethidium bromide to bovine leukocytes in fresh milk. Ethidium bromide is a fluorescent dye that is commonly used to label DNA, and hence visualize chromosomes in cells. The lifetime of

  9. An investigative approach to explore optimum assembly process design for annular targets carrying LEU foil

    Science.gov (United States)

    Hoyer, Annemarie

    Technetium-99m is the most widely used nuclear isotope in the medical field, with nearly 80 to 85% of all diagnostic imaging procedures. The daughter isotope of molybdenum-99 is currently produced using weapons-grade uranium. A suggested design for aluminum targets carrying low-enriched uranium (LEU) foil is presented for the fulfillment of eliminating highly enriched uranium (HEU) for medical isotope production. The assembly process that this research focuses on is the conventional draw-plug process which is currently used and lastly the sealing process. The research is unique in that it is a systematic approach to explore the optimal target assembly process to produce those targets with the required quality and integrity. Conducting 9 parametric experiments, aluminum tubes with a nickel foil fission-barrier and a surrogate stainless steel foil are assembled, welded and then examined to find defects, to determine residual stresses, and to find the best cost-effective target dimensions. The experimental design consists of 9 assembly combinations that were found through orthogonal arrays in order to explore the significance of each factor. Using probabilistic modeling, the parametric study is investigated using the Taguchi method of robust analysis. Depending on the situation, optimal conditions may be a nominal, a minimized or occasionally a maximized condition. The results will provide the best target design and will give optimal quality with little or no assembly defects.

  10. Production of hyaline-like cartilage by bone marrow mesenchymal stem cells in a self-assembly model.

    Science.gov (United States)

    Elder, Steven H; Cooley, Avery J; Borazjani, Ali; Sowell, Brittany L; To, Harrison; Tran, Scott C

    2009-10-01

    A scaffoldless or self-assembly approach to cartilage tissue engineering has been used to produce hyaline cartilage from bone marrow-derived mesenchymal stem cells (bMSCs), but the mechanical properties of such engineered cartilage and the effects the transforming growth factor (TGF) isoform have not been fully explored. This study employs a cell culture insert model to produce tissue-engineered cartilage using bMSCs. Neonatal pig bMSCs were isolated by plastic adherence and expanded in monolayer before being seeded into porous transwell inserts and cultured for 4 or 8 weeks in defined chondrogenic media containing either TGF-beta1 or TGF-beta3. Following biomechanical evaluation in confined compression, colorimetric dimethyl methylene blue and Sircol dye-binding assays were used to analyze glycosaminoglycan (GAG) and collagen contents, respectively. Histological sections were stained with toluidine blue for proteoglycans and with picrosirius red to reveal collagen orientation, and immunostained for detection of collagen types I and II. Neocartilage increased in thickness, collagen, and GAG content between 4 and 8 weeks. Proteoglycan concentration increased with depth from the top surface. The tissue contained much more collagen type II than type I, and there was a consistent pattern of collagen alignment. TGF-beta1-treated and TGF-beta3-treated constructs were similar at 4 weeks, but 8-week TGF-beta1 constructs had a higher aggregate modulus and GAG content compared to TGF-beta3. These results demonstrate that bMSCs can generate functional hyaline-like cartilage through a self-assembling process.

  11. Assembler absolute forward thick-target bremsstrahlung spectra program

    International Nuclear Information System (INIS)

    Niculescu, V.I.R.; Baciu, G.; Ionescu-Bujor, M.

    1981-12-01

    The program is intended to compute the absolute forward thick-target bremsstrahlung spectrum for electrons in the energy range 1-24 MeV. The program takes into account the following phenomena: multiple scattering, energy loss and the attenuation of the emitted gamma rays. The computer program is written in Assembler having a higher degree of generality and is more performant than the FORTRAN version. (authors)

  12. Evaluation of residual radioactivity and dose rate of a target assembly in an IBA cyclotron

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, Seon Yong; Kim, Young Ju; Lee, Seung Wook [School of Mechanical Engineering, Pusan National University (Korea, Republic of)

    2016-12-15

    When a cyclotron produces 18F-, accelerated protons interact with metal parts of the cyclotron machine and induces radioactivity. Especially, the target window and chamber of the target assembly are the main parts where long-lived radionuclides are generated as they are incident by direct beams. It is of great importance to identify radionuclides induced in the target assembly for the safe operation and maintenance of a cyclotron facility. In this study, we analyzed major radionuclides generated in the target assembly by an operation of the Cyclotron 18/9 machine and measured dose rates after the operation to establish the radiation safety guideline for operators and maintenance personnel of the machine. Gamma spectroscopy with HPGe was performed on samples from the target chamber and Havar foil target window to identify the radionuclides generated during the operation for production of 18F-- isotope and their specific activity. Also, the dose rates from the target were measured as a function of time after an operation. These data will help improve radiological safety of operating the cyclotron facilities.

  13. Assembling the Streptococcus thermophilus clustered regularly interspaced short palindromic repeats (CRISPR) array for multiplex DNA targeting.

    Science.gov (United States)

    Guo, Lijun; Xu, Kun; Liu, Zhiyuan; Zhang, Cunfang; Xin, Ying; Zhang, Zhiying

    2015-06-01

    In addition to the advantages of scalable, affordable, and easy to engineer, the clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated protein (Cas) technology is superior for multiplex targeting, which is laborious and inconvenient when achieved by cloning multiple gRNA expressing cassettes. Here, we report a simple CRISPR array assembling method which will facilitate multiplex targeting usage. First, the Streptococcus thermophilus CRISPR3/Cas locus was cloned. Second, different CRISPR arrays were assembled with different crRNA spacers. Transformation assays using different Escherichia coli strains demonstrated efficient plasmid DNA targeting, and we achieved targeting efficiency up to 95% with an assembled CRISPR array with three crRNA spacers. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Artificial muscle-like function from hierarchical supramolecular assembly of photoresponsive molecular motors

    NARCIS (Netherlands)

    Chen, Jiawen; Leung, Franco King-Chi; Stuart, Marc C A; Kajitani, Takashi; Fukushima, Takanori; van der Giessen, Erik; Feringa, Ben L

    A striking feature of living systems is their ability to produce motility by amplification of collective molecular motion from the nanoscale up to macroscopic dimensions. Some of nature's protein motors, such as myosin in muscle tissue, consist of a hierarchical supramolecular assembly of very large

  15. Paramyxovirus Infection Mimics In Vivo Cellular Dynamics in Three-Demensional Human Bronchio-Epithelial Tissue-Like Assemblies

    Science.gov (United States)

    Deatly, Anne M.; Lin, Yen-Huei; McCarthy, Maureen; Chen, Wei; Miller, Lynn Z.; Quiroz, Jorge; Nowak, Becky M.; Lerch, Robert A.; Udem, Stephen A.; Goodwin, Thomas J.

    2012-01-01

    Respiratory syncytial virus and parainfluenza virus cause severe respiratory disease, especially in infants, children and the elderly. An in vitro model that accurately mimics infection of the human respiratory epithelium (HRE) would facilitate vaccine development greatly. Monolayer cultures traditionally used to study these viruses do not accurately and precisely differentiate the replication efficiencies of wild type and attenuated viruses. Therefore, we engineered novel three-dimensional (3D) tissue-like assemblies (TLAs) of human broncho-epithelial (HBE) cells to produce a more physiologically relevant in vitro model of the HRE. TLAs resemble HRE structurally and by expression of differentiated epithelial cell markers. Most significantly, wild type viruses exhibited a clear growth advantage over attenuated strains in TLAs unlike monolayer cultures. In addition, the TLAs responded to virus infection by secreting pro-inflammatory mediators similar to the respiratory epithelia of infected children. These characteristics make the TLA model a valuable platform technology to develop and evaluate live, attenuated respiratory virus vaccine candidates for human use. Respiratory virus diseases, the most frequent and least preventable of all infectious diseases, range in severity from the common cold to severe bronchiolitis and pneumonia . Two paramyxoviruses, respiratory syncytial virus (RSV) and parainfluenza virus type 3 (PIV3), are responsible for a majority of the most severe respiratory diseases of infants and young children. RSV causes 70% of all bronchiolitis cases and is a major cause of morbidity and mortality worldwide, especially in infants. PIV3 causes 10-15% of bronchiolitis and pneumonia during infancy, second only to RSV, and 40% of croup in infants To date, licensed vaccines are not available to prevent these respiratory diseases. At present, traditional monkey kidney (Vero and LLC-MK2) and human (HEp-2) tissue culture cells and small animal models (mouse

  16. Study of the thermo-mechanical performances of the IFMIF-EVEDA Lithium Test Loop target assembly

    Energy Technology Data Exchange (ETDEWEB)

    Di Maio, P.A., E-mail: dimaio@din.unipa.it [Dipartimento dell' Energia, Universita di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Arena, P.; Bongiovi, G. [Dipartimento dell' Energia, Universita di Palermo, Viale delle Scienze, 90128 Palermo (Italy); Giammusso, R.; Micciche, G.; Tincani, A. [ENEA C. R. Brasimone, 40032 Camugnano, Bologna (Italy)

    2012-08-15

    Highlights: Black-Right-Pointing-Pointer IFMIF-EVEDA target assembly thermo-mechanical behavior has been investigated. Black-Right-Pointing-Pointer Finite element method has been followed and a commercial code has been used. Black-Right-Pointing-Pointer Nominal, design and pressure test steady state scenarios and start-up transient conditions have been investigated. Black-Right-Pointing-Pointer Steady state results have shown that back-plate yielding may occur only under the design scenario. Black-Right-Pointing-Pointer Transient analysis has indicated that TA start-up lasts for {approx}60 h. - Abstract: Within the framework of the IFMIF R and D program and in close cooperation with ENEA-Brasimone, at the Department of Energy of the University of Palermo a research campaign has been launched to investigate the thermo-mechanical behavior of the target assembly under both steady state and start-up transient conditions. A theoretical approach based on the finite element method (FEM) has been followed and a well-known commercial code has been adopted. A realistic 3D FEM model of the target assembly has been set-up and optimized by running a mesh independency analysis. A proper set of loads and boundary conditions, mainly concerned with radiation heat transfer between the target assembly external walls and the inner walls of its containment vessel, have been considered and the target assembly thermo-mechanical behavior under nominal, design and pressure test steady state scenarios and start-up transient conditions has been investigated. Results are herewith reported and discussed.

  17. The rapid manufacture of uniform composite multicellular-biomaterial micropellets, their assembly into macroscopic organized tissues, and potential applications in cartilage tissue engineering.

    Directory of Open Access Journals (Sweden)

    Betul Kul Babur

    Full Text Available We and others have published on the rapid manufacture of micropellet tissues, typically formed from 100-500 cells each. The micropellet geometry enhances cellular biological properties, and in many cases the micropellets can subsequently be utilized as building blocks to assemble complex macrotissues. Generally, micropellets are formed from cells alone, however when replicating matrix-rich tissues such as cartilage it would be ideal if matrix or biomaterials supplements could be incorporated directly into the micropellet during the manufacturing process. Herein we describe a method to efficiently incorporate donor cartilage matrix into tissue engineered cartilage micropellets. We lyophilized bovine cartilage matrix, and then shattered it into microscopic pieces having average dimensions < 10 μm diameter; we termed this microscopic donor matrix "cartilage dust (CD". Using a microwell platform, we show that ~0.83 μg CD can be rapidly and efficiently incorporated into single multicellular aggregates formed from 180 bone marrow mesenchymal stem/stromal cells (MSC each. The microwell platform enabled the rapid manufacture of thousands of replica composite micropellets, with each micropellet having a material/CD core and a cellular surface. This micropellet organization enabled the rapid bulking up of the micropellet core matrix content, and left an adhesive cellular outer surface. This morphological organization enabled the ready assembly of the composite micropellets into macroscopic tissues. Generically, this is a versatile method that enables the rapid and uniform integration of biomaterials into multicellular micropellets that can then be used as tissue building blocks. In this study, the addition of CD resulted in an approximate 8-fold volume increase in the micropellets, with the donor matrix functioning to contribute to an increase in total cartilage matrix content. Composite micropellets were readily assembled into macroscopic cartilage

  18. Smooth muscle-like tissue constructs with circumferentially oriented cells formed by the cell fiber technology.

    Science.gov (United States)

    Hsiao, Amy Y; Okitsu, Teru; Onoe, Hiroaki; Kiyosawa, Mahiro; Teramae, Hiroki; Iwanaga, Shintaroh; Kazama, Tomohiko; Matsumoto, Taro; Takeuchi, Shoji

    2015-01-01

    The proper functioning of many organs and tissues containing smooth muscles greatly depends on the intricate organization of the smooth muscle cells oriented in appropriate directions. Consequently controlling the cellular orientation in three-dimensional (3D) cellular constructs is an important issue in engineering tissues of smooth muscles. However, the ability to precisely control the cellular orientation at the microscale cannot be achieved by various commonly used 3D tissue engineering building blocks such as spheroids. This paper presents the formation of coiled spring-shaped 3D cellular constructs containing circumferentially oriented smooth muscle-like cells differentiated from dedifferentiated fat (DFAT) cells. By using the cell fiber technology, DFAT cells suspended in a mixture of extracellular proteins possessing an optimized stiffness were encapsulated in the core region of alginate shell microfibers and uniformly aligned to the longitudinal direction. Upon differentiation induction to the smooth muscle lineage, DFAT cell fibers self-assembled to coiled spring structures where the cells became circumferentially oriented. By changing the initial core-shell microfiber diameter, we demonstrated that the spring pitch and diameter could be controlled. 21 days after differentiation induction, the cell fibers contained high percentages of ASMA-positive and calponin-positive cells. Our technology to create these smooth muscle-like spring constructs enabled precise control of cellular alignment and orientation in 3D. These constructs can further serve as tissue engineering building blocks for larger organs and cellular implants used in clinical treatments.

  19. Neural stem cells encapsulated in a functionalized self-assembling peptide hydrogel for brain tissue engineering.

    Science.gov (United States)

    Cheng, Tzu-Yun; Chen, Ming-Hong; Chang, Wen-Han; Huang, Ming-Yuan; Wang, Tzu-Wei

    2013-03-01

    Brain injury is almost irreparable due to the poor regenerative capability of neural tissue. Nowadays, new therapeutic strategies have been focused on stem cell therapy and supplying an appropriate three dimensional (3D) matrix for the repair of injured brain tissue. In this study, we specifically linked laminin-derived IKVAV motif on the C-terminal to enrich self-assembling peptide RADA(16) as a functional peptide-based scaffold. Our purpose is providing a functional self-assembling peptide 3D hydrogel with encapsulated neural stem cells to enhance the reconstruction of the injured brain. The physiochemical properties reported that RADA(16)-IKVAV can self-assemble into nanofibrous morphology with bilayer β-sheet structure and become gelationed hydrogel with mechanical stiffness similar to brain tissue. The in vitro results showed that the extended IKVAV sequence can serve as a signal or guiding cue to direct the encapsulated neural stem cells (NSCs) adhesion and then towards neuronal differentiation. Animal study was conducted in a rat brain surgery model to demonstrate the damage in cerebral neocortex/neopallium loss. The results showed that the injected peptide solution immediately in situ formed the 3D hydrogel filling up the cavity and bridging the gaps. The histological analyses revealed the RADA(16)-IKVAV self-assembling peptide hydrogel not only enhanced survival of encapsulated NSCs but also reduced the formation of glial astrocytes. The peptide hydrogel with IKVAV extended motifs also showed the support of encapsulated NSCs in neuronal differentiation and the improvement in brain tissue regeneration after 6 weeks post-transplantation. Copyright © 2012 Elsevier Ltd. All rights reserved.

  20. A design concept of target-moderator-reflector assemblies for KENS-II

    International Nuclear Information System (INIS)

    Watanabe, N.

    1991-01-01

    A design concept of KENS-II target-moderator-reflector assemblies is described. One of the assemblies is dedicated to the cold neutron source, and the other, to the thermal and epithermal neutron source. A flux-trap type moderator-configuration was adopted with a vertical proton-beam injection scheme. All moderators for the cold neutron source are coupled liquid hydrogen moderators with premoderators. A new scheme of proton beam delivery is proposed. The new system can provide several times higher total performance than a reference system based on a traditional single assembly with all decoupled moderators in a wing geometry and with a horizontal proton-beam injection scheme. (author)

  1. In vitro assembly of a prohead-like structure of the Rhodobacter capsulatus gene transfer agent

    International Nuclear Information System (INIS)

    Spano, Anthony J.; Chen, Frank S.; Goodman, Benjamin E.; Sabat, Agnes E.; Simon, Martha N.; Wall, Joseph S.; Correia, John J.; McIvor, Wilson; Newcomb, William W.; Brown, Jay C.; Schnur, Joel M.; Lebedev, Nikolai

    2007-01-01

    The gene transfer agent (GTA) is a phage-like particle capable of exchanging double-stranded DNA fragments between cells of the photosynthetic bacterium Rhodobacter capsulatus. Here we show that the major capsid protein of GTA, expressed in E. coli, can be assembled into prohead-like structures in the presence of calcium ions in vitro. Transmission electron microscopy (TEM) of uranyl acetate staining material and thin sections of glutaraldehyde-fixed material demonstrates that these associates have spherical structures with diameters in the range of 27-35 nm. The analysis of scanning TEM images revealed particles of mass ∼ 4.3 MDa, representing 101 ± 11 copies of the monomeric subunit. The establishment of this simple and rapid method to form prohead-like particles permits the GTA system to be used for genome manipulation within the photosynthetic bacterium, for specific targeted drug delivery, and for the construction of biologically based distributed autonomous sensors for environmental monitoring

  2. Hydrangea-like magneto-fluorescent nanoparticles through thiol-inducing assembly

    Science.gov (United States)

    Chen, Shun; Zhang, Junjun; Song, Shaokun; Xiong, Chuanxi; Dong, Lijie

    2017-01-01

    Magneto-fluorescent nanoparticles (NPs), recognized as an emerging class of materials, have drawn much attention because of their potential applications. Due to surface functionalization and thiol-metal bonds, a simple method has been put forward for fabricating hydrangea-like magneto-fluorescent Fe3O4-SH@QD NPs, through assembling thiol-modified Fe3O4 NPs with sub-size multi-layer core/shell CdSe/CdS/ZnS QDs. After a refined but controllable silane hydrolysis process, thiol-modified Fe3O4 was fabricated, resulting in Fe3O4-SH@QD NPs with QDs, while preventing the quenching of the QDs. As a result, the core Fe3O4 NPs were 18 nm in diameter, while the scattered CdSe/CdS/ZnS QDs were 7 nm in diameter. The resultant magneto-fluorescent Fe3O4-SH@QD NPs exhibit efficient fluorescence, superparamagnetism at room temperature, and rapid response to the external field, which make them ideal candidates for difunctional probes in MRI and bio-labels, targeting and photodynamic therapy, and cell tracking and separation.

  3. Hantavirus Gn and Gc glycoproteins self-assemble into virus-like particles.

    Science.gov (United States)

    Acuña, Rodrigo; Cifuentes-Muñoz, Nicolás; Márquez, Chantal L; Bulling, Manuela; Klingström, Jonas; Mancini, Roberta; Lozach, Pierre-Yves; Tischler, Nicole D

    2014-02-01

    How hantaviruses assemble and exit infected cells remains largely unknown. Here, we show that the expression of Andes (ANDV) and Puumala (PUUV) hantavirus Gn and Gc envelope glycoproteins lead to their self-assembly into virus-like particles (VLPs) which were released to cell supernatants. The viral nucleoprotein was not required for particle formation. Further, a Gc endodomain deletion mutant did not abrogate VLP formation. The VLPs were pleomorphic, exposed protrusions and reacted with patient sera.

  4. Tissue engineering by self-assembly and bio-printing of living cells

    International Nuclear Information System (INIS)

    Jakab, Karoly; Marga, Francoise; Forgacs, Gabor; Norotte, Cyrille; Murphy, Keith; Vunjak-Novakovic, Gordana

    2010-01-01

    Biofabrication of living structures with desired topology and functionality requires the interdisciplinary effort of practitioners of the physical, life and engineering sciences. Such efforts are being undertaken in many laboratories around the world. Numerous approaches are pursued, such as those based on the use of natural or artificial scaffolds, decellularized cadaveric extracellular matrices and, most lately, bioprinting. To be successful in this endeavor, it is crucial to provide in vitro micro-environmental clues for the cells resembling those in the organism. Therefore, scaffolds, populated with differentiated cells or stem cells, of increasing complexity and sophistication are being fabricated. However, no matter how sophisticated scaffolds are, they can cause problems stemming from their degradation, eliciting immunogenic reactions and other a priori unforeseen complications. It is also being realized that ultimately the best approach might be to rely on the self-assembly and self-organizing properties of cells and tissues and the innate regenerative capability of the organism itself, not just simply prepare tissue and organ structures in vitro followed by their implantation. Here we briefly review the different strategies for the fabrication of three-dimensional biological structures, in particular bioprinting. We detail a fully biological, scaffoldless, print-based engineering approach that uses self-assembling multicellular units as bio-ink particles and employs early developmental morphogenetic principles, such as cell sorting and tissue fusion. (topical review)

  5. Tissue engineering by self-assembly and bio-printing of living cells

    Energy Technology Data Exchange (ETDEWEB)

    Jakab, Karoly; Marga, Francoise; Forgacs, Gabor [Department of Physics and Astronomy, University of Missouri, Columbia, MO 65211 (United States); Norotte, Cyrille [Department of Biology, University of Missouri, Columbia, MO 65211 (United States); Murphy, Keith [Organovo, Inc., 5871 Oberlin Drive, San Diego, CA 92121 (United States); Vunjak-Novakovic, Gordana, E-mail: forgacsg@missouri.ed [Department of Biomedical Engineering, Columbia University, New York, NY 10032 (United States)

    2010-06-15

    Biofabrication of living structures with desired topology and functionality requires the interdisciplinary effort of practitioners of the physical, life and engineering sciences. Such efforts are being undertaken in many laboratories around the world. Numerous approaches are pursued, such as those based on the use of natural or artificial scaffolds, decellularized cadaveric extracellular matrices and, most lately, bioprinting. To be successful in this endeavor, it is crucial to provide in vitro micro-environmental clues for the cells resembling those in the organism. Therefore, scaffolds, populated with differentiated cells or stem cells, of increasing complexity and sophistication are being fabricated. However, no matter how sophisticated scaffolds are, they can cause problems stemming from their degradation, eliciting immunogenic reactions and other a priori unforeseen complications. It is also being realized that ultimately the best approach might be to rely on the self-assembly and self-organizing properties of cells and tissues and the innate regenerative capability of the organism itself, not just simply prepare tissue and organ structures in vitro followed by their implantation. Here we briefly review the different strategies for the fabrication of three-dimensional biological structures, in particular bioprinting. We detail a fully biological, scaffoldless, print-based engineering approach that uses self-assembling multicellular units as bio-ink particles and employs early developmental morphogenetic principles, such as cell sorting and tissue fusion. (topical review)

  6. Mulberry-like dual-drug complicated nanocarriers assembled with apogossypolone amphiphilic starch micelles and doxorubicin hyaluronic acid nanoparticles for tumor combination and targeted therapy.

    Science.gov (United States)

    Li, Ke; Liu, Hao; Gao, Wei; Chen, Mu; Zeng, Yun; Liu, Jiajun; Xu, Liang; Wu, Daocheng

    2015-01-01

    A comprehensive strategy for the preparation of mulberry-like dual-drug complicated nanocarriers (MLDC NCs) with high drug loading and adjustable dual-drug ratio was developed. First, apogossypolone (ApoG2) amphiphilic starch micelles (AASt MCs) were prepared by self-assembly process, and doxorubicin (DOX) hyaluronic acid nanoparticles (DHA NPs) were prepared by DOX absorption with excess HA by electrostatic absorption. MLDC NCs were obtained by adsorption of 8-9 DHA NPs around one AASt MC via electrostatic interaction. UV-visible and fluorescence spectrophotometers were used to measure the entrapment efficiency and loading efficiency of the two drugs. Transmission electron microscope and dynamic light scattering method were used to observe the size distribution and morphology of the particles. The tumor-targeting feature caused by HA-receptor mediation was confirmed by in vitro cell uptake and in vivo near-infrared fluorescence imaging. MLDC NCs were found to possess a mulberry-like shape with a dynamic size of 83.1 ± 6.6 nm. The final encapsulation efficiencies of ApoG2 and DOX in MLDC NCs were 94 ± 1.7% and 87 ± 5.8% with respect to drug-loading capacities of 13.3 ± 1.2% and 13.1 ± 3.7%, respectively. Almost no ApoG2 release was found within 80 h and less than 30% of DOX was released into the outer phase even after 72 h. In vivo fluorescence imaging revealed that MLDC NCs had highly efficient targeting and accumulation at the tumor in vivo and was maintained for 96 h after being injected intravenously in mice. Low LD50 for the two drugs in MLDC NCs was found after acute toxicity test. One-fifth normal dosage of the two drugs in MLDC NCs exhibited significantly higher anti-tumor efficiency in reducing tumor size compared with free drugs combination or single drug-loaded nanoparticles individually, indicating that the mulberry-like dual-drug nanoplatform has a great potential in tumor therapy. Copyright © 2014 Elsevier Ltd. All rights

  7. Current Molecular Targeted Therapies for Bone and Soft Tissue Sarcomas

    Directory of Open Access Journals (Sweden)

    Kenji Nakano

    2018-03-01

    Full Text Available Systemic treatment options for bone and soft tissue sarcomas remained unchanged until the 2000s. These cancers presented challenges in new drug development partly because of their rarity and heterogeneity. Many new molecular targeting drugs have been tried in the 2010s, and some were approved for bone and soft tissue sarcoma. As one of the first molecular targeted drugs approved for solid malignant tumors, imatinib’s approval as a treatment for gastrointestinal stromal tumors (GISTs has been a great achievement. Following imatinib, other tyrosine kinase inhibitors (TKIs have been approved for GISTs such as sunitinib and regorafenib, and pazopanib was approved for non-GIST soft tissue sarcomas. Olaratumab, the monoclonal antibody that targets platelet-derived growth factor receptor (PDGFR-α, was shown to extend the overall survival of soft tissue sarcoma patients and was approved in 2016 in the U.S. as a breakthrough therapy. For bone tumors, new drugs are limited to denosumab, a receptor activator of nuclear factor κB ligand (RANKL inhibitor, for treating giant cell tumors of bone. In this review, we explain and summarize the current molecular targeting therapies approved and in development for bone and soft tissue sarcomas.

  8. Double-hydrophobic elastin-like polypeptides with added functional motifs: Self-assembly and cytocompatibility.

    Science.gov (United States)

    Le, Duc H T; Tsutsui, Yoko; Sugawara-Narutaki, Ayae; Yukawa, Hiroshi; Baba, Yoshinobu; Ohtsuki, Chikara

    2017-09-01

    We have recently developed a novel double-hydrophobic elastin-like triblock polypeptide called GPG, designed after the uneven distribution of two different hydrophobic domains found in elastin, an extracellular matrix protein providing elasticity and resilience to tissues. Upon temperature trigger, GPG undergoes a sequential self-assembling process to form flexible beaded nanofibers with high homogeneity and excellent dispersibility in water. Given that GPG might be a potential elastin-mimetic material, we sought to explore the biological activities of this block polypeptide. Besides GPG, several functionalized derivatives were also constructed by fusing functional motifs such as KAAK or KAAKGRGDS at the C-terminal of GPG. Although the added motifs affected the kinetics of fiber formation and β-sheet contents, all three GPGs assembled into beaded nanofibers at the physiological temperature. The resulting GPG nanofibers preserved their beaded structures in cell culture medium; therefore, they were coated on polystyrene substrates to study their cytocompatibility toward mouse embryonic fibroblasts, NIH-3T3. Among the three polypeptides, GPG having the cell-binding motif GRGDS derived from fibronectin showed excellent cell adhesion and cell proliferation properties compared to other conventional materials, suggesting its promising applications as extracellular matrices for mammalian cells. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 2475-2484, 2017. © 2017 Wiley Periodicals, Inc.

  9. New Therapeutic Targets in Soft Tissue Sarcoma

    Science.gov (United States)

    Demicco, Elizabeth G; Maki, Robert G; Lev, Dina C.; Lazar, Alexander J

    2012-01-01

    Soft tissue sarcomas are an uncommon and diverse group of more than 50 mesenchymal malignancies. The pathogenesis of many of these is poorly understood, but others have begun to reveal the secrets of their inner workings. With considerable effort over recent years, soft tissue sarcomas have increasingly been classified on the basis of underlying molecular alterations. In turn, this has allowed the development and application of targeted agents in several specific, molecularly defined, sarcoma subtypes. This review will focus the rationale for targeted therapy in sarcoma, with emphasis on the relevance of specific molecular factors and pathways in both translocation-associated sarcomas and in genetically complex tumors. In addition, we will address some of the early successes in sarcoma targeted therapy as well as a few challenges and disappointments in this field. Finally we will discuss several possible opportunities represented by poorly understood, but potentially promising new therapeutic targets, as well as several novel biologic agents currently in preclinical and early phase I/II trials. This will provide the reader with context for understanding the current state this field and a sense of where it may be headed in the coming years. PMID:22498582

  10. Geometric triangular chiral hexagon crystal-like complexes organization in pathological tissues biological collision order.

    Directory of Open Access Journals (Sweden)

    Jairo A Díaz

    Full Text Available The present study describes and documents self-assembly of geometric triangular chiral hexagon crystal like complex organizations (GTCHC in human pathological tissues. The authors have found this architectural geometric expression at macroscopic and microscopic levels mainly in cancer processes. This study is based essentially on macroscopic and histopathologic analyses of 3000 surgical specimens: 2600 inflammatory lesions and 400 malignant tumours. Geometric complexes identified photographically at macroscopic level were located in the gross surgical specimen, and these areas were carefully dissected. Samples were taken to carry out histologic analysis. Based on the hypothesis of a collision genesis mechanism and because it is difficult to carry out an appropriate methodological observation in biological systems, the authors designed a model base on other dynamic systems to obtain indirect information in which a strong white flash wave light discharge, generated by an electronic device, hits over the lines of electrical conductance structured in helicoidal pattern. In their experimental model, the authors were able to reproduce and to predict polarity, chirality, helicoid geometry, triangular and hexagonal clusters through electromagnetic sequential collisions. They determined that similar events among constituents of extracelular matrix which drive and produce piezoelectric activity are responsible for the genesis of GTCHC complexes in pathological tissues. This research suggests that molecular crystals represented by triangular chiral hexagons derived from a collision-attraction event against collagen type I fibrils emerge at microscopic and macroscopic scales presenting a lateral assembly of each side of hypertrophy helicoid fibers, that represent energy flow in cooperative hierarchically chiral electromagnetic interaction in pathological tissues and arises as a geometry of the equilibrium in perturbed biological systems. Further

  11. Geometric triangular chiral hexagon crystal-like complexes organization in pathological tissues biological collision order.

    Science.gov (United States)

    Díaz, Jairo A; Jaramillo, Natalia A; Murillo, Mauricio F

    2007-12-12

    The present study describes and documents self-assembly of geometric triangular chiral hexagon crystal like complex organizations (GTCHC) in human pathological tissues. The authors have found this architectural geometric expression at macroscopic and microscopic levels mainly in cancer processes. This study is based essentially on macroscopic and histopathologic analyses of 3000 surgical specimens: 2600 inflammatory lesions and 400 malignant tumours. Geometric complexes identified photographically at macroscopic level were located in the gross surgical specimen, and these areas were carefully dissected. Samples were taken to carry out histologic analysis. Based on the hypothesis of a collision genesis mechanism and because it is difficult to carry out an appropriate methodological observation in biological systems, the authors designed a model base on other dynamic systems to obtain indirect information in which a strong white flash wave light discharge, generated by an electronic device, hits over the lines of electrical conductance structured in helicoidal pattern. In their experimental model, the authors were able to reproduce and to predict polarity, chirality, helicoid geometry, triangular and hexagonal clusters through electromagnetic sequential collisions. They determined that similar events among constituents of extracelular matrix which drive and produce piezoelectric activity are responsible for the genesis of GTCHC complexes in pathological tissues. This research suggests that molecular crystals represented by triangular chiral hexagons derived from a collision-attraction event against collagen type I fibrils emerge at microscopic and macroscopic scales presenting a lateral assembly of each side of hypertrophy helicoid fibers, that represent energy flow in cooperative hierarchically chiral electromagnetic interaction in pathological tissues and arises as a geometry of the equilibrium in perturbed biological systems. Further interdisciplinary studies must

  12. Tumor suppressor roles of CENP-E and Nsl1 in Drosophila epithelial tissues.

    Science.gov (United States)

    Clemente-Ruiz, Marta; Muzzopappa, Mariana; Milán, Marco

    2014-01-01

    Depletion of spindle assembly checkpoint (SAC) genes in Drosophila epithelial tissues leads to JNK-dependent programmed cell death and additional blockade of the apoptotic program drives tumorigenesis. A recent report proposes that chromosomal instability (CIN) is not the driving force in the tumorigenic response of the SAC-deficient tissue, and that checkpoint proteins exert a SAC-independent tumor suppressor role. This notion is based on observations that the depletion of CENP-E levels or prevention of Bub3 from binding to the kinetochore in Drosophila tissues unable to activate the apoptotic program induces CIN but does not cause hyperproliferation. Here we re-examined this proposal. In contrast to the previous report, we observed that depletion of CENP-E or Nsl1-the latter mediating kinetochore targeting of Bub3-in epithelial tissues unable to activate the apoptotic program induces significant levels of aneuploidy and drives tumor-like growth. The induction of the JNK transcriptional targets Wingless, a mitogenic molecule, and MMP1, a matrix metaloproteinase 1 involved in basement membrane degradation was also observed in these tumors. An identical response of the tissue was previously detected upon depletion of several SAC genes or genes involved in spindle assembly, chromatin condensation, and cytokinesis, all of which have been described to cause CIN. All together, these results reinforce the role of CIN in driving tumorigenesis in Drosophila epithelial tissues and question the proposed SAC-independent roles of checkpoint proteins in suppressing tumorigenesis. Differences in aneuploidy rates might explain the discrepancy between the previous report and our results.

  13. The group A streptococcal collagen-like protein 1, Scl1, mediates biofilm formation by targeting the EDA-containing variant of cellular fibronectin expressed in wounded tissue

    Science.gov (United States)

    Oliver-Kozup, Heaven; Martin, Karen H.; Schwegler-Berry, Diane; Green, Brett J.; Betts, Courtney; Shinde, Arti V.; Van De Water, Livingston; Lukomski, Slawomir

    2012-01-01

    Summary Wounds are known to serve as portals of entry for group A Streptococcus (GAS). Subsequent tissue colonization is mediated by interactions between GAS surface proteins and host extracellular matrix components. We recently reported that the streptococcal collagen-like protein-1, Scl1, selectively binds the cellular form of fibronectin (cFn) and also contributes to GAS biofilm formation on abiotic surfaces. One structural feature of cFn, which is predominantly expressed in response to tissue injury, is the presence of a spliced variant containing extra domain A (EDA/EIIIA). We now report that GAS biofilm formation is mediated by the Scl1 interaction with EDA-containing cFn. Recombinant Scl1 proteins that bound cFn also bound recombinant EDA within the C-C′ loop region recognized by the α9β1 integrin. The extracellular 2-D matrix derived from human dermal fibroblasts supports GAS adherence and biofilm formation. Altogether, this work identifies and characterizes a novel molecular mechanism by which GAS utilizes Scl1 to specifically target an extracellular matrix component that is predominantly expressed at the site of injury in order to secure host tissue colonization. PMID:23217101

  14. Folate mediated self-assembled phytosterol-alginate nanoparticles for targeted intracellular anticancer drug delivery.

    Science.gov (United States)

    Wang, Jianting; Wang, Ming; Zheng, Mingming; Guo, Qiong; Wang, Yafan; Wang, Heqing; Xie, Xiangrong; Huang, Fenghong; Gong, Renmin

    2015-05-01

    Self-assembled core/shell nanoparticles (NPs) were synthesized from water-soluble alginate substituted by hydrophobic phytosterols. Folate, a cancer-cell-specific ligand, was conjugated to the phytosterol-alginate (PA) NPs for targeting folate-receptor-overexpressing cancer cells. The physicochemical properties of folate-phytosterol-alginate (FPA) NPs were characterized by nuclear magnetic resonance, transmission electron microscopy, dynamic light scattering, electrophoretic light scattering, and fluorescence spectroscopy. Doxorubicin (DOX), an anticancer drug, was entrapped inside prepared NPs by dialysis method. The identification of prepared FPA NPs to folate-receptor-overexpressing cancer cells (KB cells) was confirmed by cytotoxicity and folate competition assays. Compared to the pure DOX and DOX/PA NPs, the DOX/FPA NPs had lower IC50 value to KB cells because of folate-receptor-mediated endocytosis process and the cytotoxicity of DOX/FPA NPs to KB cells could be competitively inhibited by free folate. The cellular uptake and internalization of pure DOX and DOX/FPA NPs was confirmed by confocal laser scanning microscopy image and the higher intracellular uptake of drug for DOX/FPA NPs over pure DOX was observed. The FPA NPs had the potential as a promising carrier to target drugs to cancer cells overexpressing folate receptors and avoid cytotoxicity to normal tissues. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. Liver-targeting of interferon-alpha with tissue-specific domain antibodies.

    Directory of Open Access Journals (Sweden)

    Edward Coulstock

    Full Text Available Interferon alpha (IFNα is used for the treatment of hepatitis C infection and whilst efficacious it is associated with multiple adverse events including reduced leukocyte, erythrocyte, and platelet counts, fatigue, and depression. These events are most likely caused by systemic exposure to interferon. We therefore hypothesise that targeting the therapeutic directly to the intended site of action in the liver would reduce exposure in blood and peripheral tissue and hence improve the safety and tolerability of IFNα therapy. We genetically fused IFN to a domain antibody (dAb specific to a hepatocyte restricted antigen, asialoglycoprotein receptor (ASGPR. Our results show that the murine IFNα2 homolog (mIFNα2 fused to an ASGPR specific dAb, termed DOM26h-196-61, could be expressed in mammalian tissue culture systems and retains the desirable biophysical properties and activity of both fusion partners when measured in vitro. Furthermore a clear increase in in vivo targeting of the liver by mIFNα2-ASGPR dAb fusion protein, compared to that observed with either unfused mIFNα2 or mIFNα2 fused to an isotype control dAb VHD2 (which does not bind ASGPR was demonstrated using microSPECT imaging. We suggest that these findings may be applicable in the development of a liver-targeted human IFN molecule with improved safety and patient compliance in comparison to the current standard of care, which could ultimately be used as a treatment for human hepatitis virus infections.

  16. Immunohistochemical evaluation of molecular radiotherapy target expression in neuroblastoma tissue

    Energy Technology Data Exchange (ETDEWEB)

    Gains, Jennifer E.; Gaze, Mark N. [University College London Hospitals NHS Foundation Trust, Department of Oncology, London (United Kingdom); Sebire, Neil J. [Great Ormond Street Hospital for Children NHS Foundation Trust, Department of Pathology, London (United Kingdom); Moroz, Veronica; Wheatley, Keith [University of Birmingham, Cancer Research UK Clinical Trials Unit, Birmingham (United Kingdom)

    2018-03-15

    Neuroblastoma may be treated with molecular radiotherapy, {sup 131}I meta-Iodobenzylguanidine and {sup 177}Lu Lutetium DOTATATE, directed at distinct molecular targets: Noradrenaline Transporter Molecule (NAT) and Somatostatin Receptor (SSTR2), respectively. This study used immunohistochemistry to evaluate target expression in archival neuroblastoma tissue, to determine whether it might facilitate clinical use of molecular radiotherapy. Tissue bank samples of formalin fixed paraffin embedded neuroblastoma tissue from patients for whom clinical outcome data were available were sectioned and stained with haematoxylin and eosin, and monoclonal antibodies directed against NAT and SSTR2. Sections were examined blinded to clinical information and scored for the percentage and intensity of tumour cells stained. These data were analysed in conjunction with clinical data. Tissue from 75 patients was examined. Target expression scores varied widely between patients: NAT median 45%, inter-quartile range 25% - 65%; and SSTR2 median 55%, interquartile range 30% - 80%; and in some cases heterogeneity of expression between different parts of a tumour was observed. A weak positive correlation was observed between the expression scores of the different targets: correlation coefficient = 0.23, p = 0.05. MYCN amplified tumours had lower SSTR2 scores: mean difference 23% confidence interval 8% - 39%, p < 0.01. Survival did not differ by scores. As expression of both targets is variable and heterogeneous, imaging assessment of both may yield more clinical information than either alone. The clinical value of immunohistochemical assessment of target expression requires prospective evaluation. Variable target expression within a patient may contribute to treatment failure. (orig.)

  17. Inverse design of multicomponent assemblies

    Science.gov (United States)

    Piñeros, William D.; Lindquist, Beth A.; Jadrich, Ryan B.; Truskett, Thomas M.

    2018-03-01

    Inverse design can be a useful strategy for discovering interactions that drive particles to spontaneously self-assemble into a desired structure. Here, we extend an inverse design methodology—relative entropy optimization—to determine isotropic interactions that promote assembly of targeted multicomponent phases, and we apply this extension to design interactions for a variety of binary crystals ranging from compact triangular and square architectures to highly open structures with dodecagonal and octadecagonal motifs. We compare the resulting optimized (self- and cross) interactions for the binary assemblies to those obtained from optimization of analogous single-component systems. This comparison reveals that self-interactions act as a "primer" to position particles at approximately correct coordination shell distances, while cross interactions act as the "binder" that refines and locks the system into the desired configuration. For simpler binary targets, it is possible to successfully design self-assembling systems while restricting one of these interaction types to be a hard-core-like potential. However, optimization of both self- and cross interaction types appears necessary to design for assembly of more complex or open structures.

  18. Assistant in design of tissue targeting leads with radio-combinatorial screening vivo

    International Nuclear Information System (INIS)

    Liu Ciyi; Zeng Jun; Xie Wenhui; Hu Silong; Jin Muxiu

    2004-01-01

    The diagnostic and therapeutic efficiency of drug depends highly on the drug distribution in target tissues (tumor for example) both specifically and accumulatively. We report here a powerful approach in design of tissue targeting leads with the assistant of radio-combinatorial screening technique developed in our laboratory. Methods: The C-terminal amide tripeptide libraries were synthesized on Rink Amide-MBHA resin in the OXX aO1OXaO1O2O positional scanning format and iterative protoco. A technetium (V) oxo core[(TcO)3+] was bound to the N4-triligands of tripeptide libraries via four deprotonated anfide nitrogen atoms to form a structure of 99Tcm-tripeptoid libraries. The radio-combinatorial screening (RCS) in vivo was then carried out after SD rats and A549 tumor bearing mice received i.v. with 99Tcm-tripeptoid libraries. Results: Signals of tissue distribution and metabolism of libraries were recorded by g counting or imaging. From library of 8,000 99Tcm-tripeptoid members, the tissue targeting leads had been identified by RCS. Those included 99Tcm-DSG (RES), 99Tcm-VAA, and 99Tcm-VIG that had specific tissue targeting in kidney, stomach, and liver respectively. The percent injected dose per gram tissue (%ID/g) of 99Tcm labeled leads in their target tissues was highly structure-dependent The discovery of 99Tcm-VAA and 99Tcm-VIG indicates that side chain methyl at positionl and 2 are crucial for stomach and liver accumulating 99Tcm-tripeptoids. In the case of kidney targeting, Ser in the position 2 and 3 is crucial for 99Tcm-tripeptoids renal excretion and accumulation characteristics respectively. Conclusion: RCS in vivo is a powerful tool for design of tissue targeting leads. (authors)

  19. Self-Assembled Smart Nanocarriers for Targeted Drug Delivery.

    Science.gov (United States)

    Cui, Wei; Li, Junbai; Decher, Gero

    2016-02-10

    Nanostructured drug-carrier systems promise numerous benefits for drug delivery. They can be engineered to precisely control drug-release rates or to target specific sites within the body with a specific amount of therapeutic agent. However, to achieve the best therapeutic effects, the systems should be designed for carrying the optimum amount of a drug to the desired target where it should be released at the optimum rate for a specified time. Despite numerous attempts, fulfilling all of these requirements in a synergistic way remains a huge challenge. The trend in drug delivery is consequently directed toward integrated multifunctional carrier systems, providing selective recognition in combination with sustained or triggered release. Capsules as vesicular systems enable drugs to be confined for controlled release. Furthermore, carriers modified with recognition groups can enhance the capability of encapsulated drug efficacy. Here, recent advances are reviewed regarding designing and preparing assembled capsules with targeting ligands or size controllable for selective recognition in drug delivery. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Erlotinib induced target-like purpura.

    Science.gov (United States)

    Rungtrakulchai, R; Rerknimitr, P

    2014-02-18

    Erlotinib is an epidermal growth factor receptor (EGFR) inhibitor, used as a treatment for advanced stage cancer. The most common side effect is cutaneous toxicity including the already known papulopustular reaction. We herein report a case of erlotinib induced target-like purpura, a peculiar cutaneous adverse event. A 57-year-old patient with advanced non-small cell lung cancer was treated by erolotinib 150 mg daily. After taking the drug for three days, an unusual target-like purpura developed on her lower legs. Skin biopsy specimen taken from the lesion revealed an extravasation of erythrocytes in the upper dermis without destruction of blood vessel walls. This skin eruption cleared after the drug was withdrawn and recurred after erlotinib was re-challenged. The mechanism underlying this cutaneous adverse event remains to be elucidated. Physicians should be aware of the rare side effect of this increasingly used drug.

  1. Engineering complex tissue-like microgel arrays for evaluating stem cell differentiation

    DEFF Research Database (Denmark)

    Guermani, Enrico; Shaki, Hossein; Mohanty, Soumyaranjan

    2016-01-01

    Development of tissue engineering scaffolds with native-like biology and microarchitectures is a prerequisite for stem cell mediated generation of off-the-shelf-tissues. So far, the field of tissue engineering has not full-filled its grand potential of engineering such combinatorial scaffolds...... for engineering functional tissues. This is primarily due to the many challenges associated with finding the right microarchitectures and ECM compositions for optimal tissue regeneration. Here, we have developed a new microgel array to address this grand challenge through robotic printing of complex stem cell...... platform will be used for high-throughput identification of combinatorial and native-like scaffolds for tissue engineering of functional organs....

  2. Novel tumor-targeting, self-assembling peptide nanofiber as a carrier for effective curcumin delivery

    Directory of Open Access Journals (Sweden)

    Liu J

    2013-12-01

    Full Text Available Jianfeng Liu, Jinjian Liu, Hongyan Xu, Yumin Zhang, Liping Chu, Qingfen Liu, Naling Song, Cuihong YangTianjin Key Laboratory of Molecular Nuclear Medicine, Institute of Radiation Medicine, Chinese Academy of Medical Science and Peking Union Medical College, People's Republic of ChinaAbstract: The poor aqueous solubility and low bioavailability of curcumin restrict its clinical application for cancer treatment. In this study, a novel tumor-targeting nanofiber carrier was developed to improve the solubility and tumor-targeting ability of curcumin using a self-assembled Nap-GFFYG-RGD peptide. The morphologies of the peptide nanofiber and the curcumin-encapsulated nanofiber were visualized by transmission electron microscopy. The tumor-targeting activity of the curcumin-encapsulated Nap-GFFYG-RGD peptide nanofiber (f-RGD-Cur was studied in vitro and in vivo, using Nap-GFFYG-RGE peptide nanofiber (f-RGE-Cur as the control. Curcumin was encapsulated into the peptide nanofiber, which had a diameter of approximately 10–20 nm. Curcumin showed sustained-release behavior from the nanofibers in vitro. f-RGD-Cur showed much higher cellular uptake in αvβ3 integrin-positive HepG2 liver carcinoma cells than did non-targeted f-RGE-Cur, thereby leading to significantly higher cytotoxicity. Ex vivo studies further demonstrated that curcumin could accumulate markedly in mouse tumors after administration of f-RGD-Cur via the tail vein. These results indicate that Nap-GFFYG-RGD peptide self-assembled nanofibers are a promising hydrophobic drug delivery system for targeted treatment of cancer.Keywords: nanofiber, tumor-targeting, self-assembling, curcumin, drug delivery

  3. Radiopharmaceuticals for localization in target tissues exhibiting a regional pH shift relative to surrounding tissues

    International Nuclear Information System (INIS)

    Blau, M.; Kung, H.F.

    1981-01-01

    This patent relates to the preparation and use of radiopharmaceutical chemical compounds comprising a radioactive isotope, other than an isotope of iodine, in chemical combination with at least one primary, secondary or tertiary amino group. The compounds have a lipophilicity sufficiently high at a pH of 7.6 to permit passage of the compound from the blood of a mammal into a target organ or tissue and sufficiently low at a pH of 6.6 to prevent rapid return of the compound from the target organ or tissue to the blood. The compounds have a percent protein binding of less than ninety percent. These compounds may be selectively deposited in at least one target tissue or organ of a mammal, the tissue or organ of which has a significantly different intracellular pH than the blood of the mammal, by introducing the compound of the invention into the bloodstream of the mammal. A plurality of selenide compounds containing Se-75 isotope are claimed in relation to the patent. (U.K.)

  4. Novel apigenin-loaded sodium hyaluronate nano-assemblies for targeting tumor cells.

    Science.gov (United States)

    Zhao, Ting; He, Yue; Chen, Huali; Bai, Yan; Hu, Wenjing; Zhang, Liangke

    2017-12-01

    We aimed to construct a novel nano-assembly carrying apigenin (APG), a hydrophobic drug, and to evaluate its in vitro targeting ability for A549 cells overexpressing CD44 receptors. The apigenin-loaded sodium hyaluronate nano-assemblies (APG/SH-NAs) were assembled by multiple non-covalent interactions between sodium hyaluronate (SH) and APG. The prepared APG/SH-NAs exhibited a small average size and narrow particle size distribution. In addition, satisfactory encapsulation efficiency and drug loading were obtained. The drug release curves indicated that APG/SH-NAs achieved a sustainable drug-release effect due to the presence of hydrophilic materials. The in vitro cytotoxicity of APG/SH-NAs against A549 cells and HepG2 cells was evaluated, and the results indicated that the prepared APG/SH-NA showed higher cytotoxicity compared to apigenin suspensions. When CD44 receptors on the surface of A549 cells were blocked by the addition of excess SH, the cytotoxicity of APG/SH-NA was significantly reduced. However, similar phenomena were not observed in HepG2 cells with relatively low CD44 receptor expression. The resulting APG/SH-NAs could efficiently facilitate the internalization of APG into A549 cells, which might be due to their high affinity for CD44 receptors. Moreover, the apoptotic rate of APG/SH-NAs through receptor-mediated endocytosis mechanism was higher than that of the other groups in A549 cells. Thus, such nano-assemblies were considered to be an effective transport system with excellent affinity for CD44 receptors to allow the SH-mediated targeted delivery of APG. Copyright © 2017. Published by Elsevier Ltd.

  5. Assembly of silver Trigons into a buckyball-like Ag180 nanocage

    Science.gov (United States)

    Wang, Zhi; Su, Hai-Feng; Tan, Yuan-Zhi; Schein, Stan; Lin, Shui-Chao; Liu, Wei; Wang, Shu-Ao; Wang, Wen-Guang; Tung, Chen-Ho; Zheng, Lan-Sun

    2017-01-01

    Buckminsterfullerene (C60) represents a perfect combination of geometry and molecular structural chemistry. It has inspired many creative ideas for building fullerene-like nanopolyhedra. These include other fullerenes, virus capsids, polyhedra based on DNA, and synthetic polynuclear metal clusters and cages. Indeed, the regular organization of large numbers of metal atoms into one highly complex structure remains one of the foremost challenges in supramolecular chemistry. Here we describe the design, synthesis, and characterization of a Ag180 nanocage with 180 Ag atoms as 4-valent vertices (V), 360 edges (E), and 182 faces (F)––sixty 3-gons, ninety 4-gons, twelve 5-gons, and twenty 6-gons––in agreement with Euler’s rule V − E + F = 2. If each 3-gon (or silver Trigon) were replaced with a carbon atom linked by edges along the 4-gons, the result would be like C60, topologically a truncated icosahedron, an Archimedean solid with icosahedral (Ih) point-group symmetry. If C60 can be described mathematically as a curling up of a 6.6.6 Platonic tiling, the Ag180 cage can be described as a curling up of a 3.4.6.4 Archimedean tiling. High-resolution electrospray ionization mass spectrometry reveals that {Ag3}n subunits coexist with the Ag180 species in the assembly system before the final crystallization of Ag180, suggesting that the silver Trigon is the smallest building block in assembly of the final cage. Thus, we assign the underlying growth mechanism of Ag180 to the Silver-Trigon Assembly Road (STAR), an assembly path that might be further employed to fabricate larger, elegant silver cages. PMID:29087328

  6. Modulated growth, stability and interactions of liquid-like coacervate assemblies of elastin.

    Science.gov (United States)

    Muiznieks, Lisa D; Cirulis, Judith T; van der Horst, Astrid; Reinhardt, Dieter P; Wuite, Gijs J L; Pomès, Régis; Keeley, Fred W

    2014-06-01

    Elastin self-assembles from monomers into polymer networks that display elasticity and resilience. The first major step in assembly is a liquid-liquid phase separation known as coacervation. This process represents a continuum of stages from initial phase separation to early growth of droplets by coalescence and later "maturation" leading to fiber formation. Assembly of tropoelastin-rich globules is on pathway for fiber formation in vivo. However, little is known about these intermediates beyond their size distribution. Here we investigate the contribution of sequence and structural motifs from full-length tropoelastin and a set of elastin-like polypeptides to the maturation of coacervate assemblies, observing their growth, stability and interaction behavior, and polypeptide alignment within matured globules. We conclude that maturation is driven by surface properties, leading to stabilization of the interface between the hydrophobic interior and aqueous solvent, potentially through structural motifs, and discuss implications for droplet interactions in fiber formation. Copyright © 2014. Published by Elsevier B.V.

  7. Hierarchical Targeting Strategy for Enhanced Tumor Tissue Accumulation/Retention and Cellular Internalization.

    Science.gov (United States)

    Wang, Sheng; Huang, Peng; Chen, Xiaoyuan

    2016-09-01

    Targeted delivery of therapeutic agents is an important way to improve the therapeutic index and reduce side effects. To design nanoparticles for targeted delivery, both enhanced tumor tissue accumulation/retention and enhanced cellular internalization should be considered simultaneously. So far, there have been very few nanoparticles with immutable structures that can achieve this goal efficiently. Hierarchical targeting, a novel targeting strategy based on stimuli responsiveness, shows good potential to enhance both tumor tissue accumulation/retention and cellular internalization. Here, the recent design and development of hierarchical targeting nanoplatforms, based on changeable particle sizes, switchable surface charges and activatable surface ligands, will be introduced. In general, the targeting moieties in these nanoplatforms are not activated during blood circulation for efficient tumor tissue accumulation, but re-activated by certain internal or external stimuli in the tumor microenvironment for enhanced cellular internalization. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Targeting and Assembly of Components of the TOC Protein Import Complex at the Chloroplast Outer Envelope Membrane

    Directory of Open Access Journals (Sweden)

    Lynn G.L. Richardson

    2014-06-01

    Full Text Available The translocon at the outer envelope membrane of chloroplasts (TOC initiates the import of thousands of nuclear encoded preproteins required for chloroplast biogenesis and function. The multimeric TOC complex contains two GTP-regulated receptors, Toc34 and Toc159, which recognize the transit peptides of preproteins and initiate protein import through a β–barrel membrane channel, Toc75. Different isoforms of Toc34 and Toc159 assemble with Toc75 to form structurally and functionally diverse translocons, and the composition and levels of TOC translocons is required for the import of specific subsets of coordinately expressed proteins during plant growth and development. Consequently, the proper assembly of the TOC complexes is key to ensuring organelle homeostasis. This review will focus on our current knowledge of the targeting and assembly of TOC components to form functional translocons at the outer membrane. Our analyses reveal that the targeting of TOC components involves elements common to the targeting of other outer membrane proteins, but also include unique features that appear to have evolved to specifically facilitate assembly of the import apparatus.

  9. Targeting and assembly of components of the TOC protein import complex at the chloroplast outer envelope membrane.

    Science.gov (United States)

    Richardson, Lynn G L; Paila, Yamuna D; Siman, Steven R; Chen, Yi; Smith, Matthew D; Schnell, Danny J

    2014-01-01

    The translocon at the outer envelope membrane of chloroplasts (TOC) initiates the import of thousands of nuclear encoded preproteins required for chloroplast biogenesis and function. The multimeric TOC complex contains two GTP-regulated receptors, Toc34 and Toc159, which recognize the transit peptides of preproteins and initiate protein import through a β-barrel membrane channel, Toc75. Different isoforms of Toc34 and Toc159 assemble with Toc75 to form structurally and functionally diverse translocons, and the composition and levels of TOC translocons is required for the import of specific subsets of coordinately expressed proteins during plant growth and development. Consequently, the proper assembly of the TOC complexes is key to ensuring organelle homeostasis. This review will focus on our current knowledge of the targeting and assembly of TOC components to form functional translocons at the outer membrane. Our analyses reveal that the targeting of TOC components involves elements common to the targeting of other outer membrane proteins, but also include unique features that appear to have evolved to specifically facilitate assembly of the import apparatus.

  10. Listeriolysin S Is a Streptolysin S-Like Virulence Factor That Targets Exclusively Prokaryotic Cells In Vivo

    Directory of Open Access Journals (Sweden)

    Juan J. Quereda

    2017-04-01

    Full Text Available Streptolysin S (SLS-like virulence factors from clinically relevant Gram-positive pathogens have been proposed to behave as potent cytotoxins, playing key roles in tissue infection. Listeriolysin S (LLS is an SLS-like hemolysin/bacteriocin present among Listeria monocytogenes strains responsible for human listeriosis outbreaks. As LLS cytotoxic activity has been associated with virulence, we investigated the LLS-specific contribution to host tissue infection. Surprisingly, we first show that LLS causes only weak red blood cell (RBC hemolysis in vitro and neither confers resistance to phagocytic killing nor favors survival of L. monocytogenes within the blood cells or in the extracellular space (in the plasma. We reveal that LLS does not elicit specific immune responses, is not cytotoxic for eukaryotic cells, and does not impact cell infection by L. monocytogenes. Using in vitro cell infection systems and a murine intravenous infection model, we actually demonstrate that LLS expression is undetectable during infection of cells and murine inner organs. Importantly, upon intravenous animal inoculation, L. monocytogenes is found in the gastrointestinal system, and only in this environment LLS expression is detected in vivo. Finally, we confirm that LLS production is associated with destruction of target bacteria. Our results demonstrate therefore that LLS does not contribute to L. monocytogenes tissue injury and virulence in inner host organs as previously reported. Moreover, we describe that LlsB, a putative posttranslational modification enzyme encoded in the LLS operon, is necessary for murine inner organ colonization. Overall, we demonstrate that LLS is the first SLS-like virulence factor targeting exclusively prokaryotic cells during in vivo infections.

  11. Commissioning a Rotating Target Wheel Assembly for Heavy Element Studies

    Science.gov (United States)

    Fields, L. D.; Bennett, M. E.; Mayorov, D. A.; Folden, C. M.

    2013-10-01

    The heaviest elements are produced artificially by fusing nuclei of light elements within an accelerator to form heavier nuclei. The most direct method to increase the production rate of nuclei is to increase the beam intensity, necessitating the use of a rotating target to minimize damage to the target by deposited heat. Such a target wheel was constructed for heavy element research at Texas A&M University, Cyclotron Institute, consisting of a wheel with three banana-shaped target cutouts. The target is designed to rotate at 1700 rpm, and a fiber optic cable provides a signal to trigger beam pulsing in order to avoid irradiating the spokes between target segments. Following minor mechanical modifications and construction of a dedicated electrical panel, the rotating target assembly was commissioned for a beam experiment. A 15 MeV/u beam of 20Ne was delivered from the K500 cyclotron and detected by a ruggedized silicon detector. The beam pulsing response time was characterized as a function of the rational frequency of the target wheel. Preliminary analysis suggests that the K500 is capable of pulsing at rates of up to 250 Hz, which is sufficient for planned future experiments. Funded by DOE and NSF-REU Program.

  12. Gold-nanoparticle-mediated jigsaw-puzzle-like assembly of supersized plasmonic DNA origami.

    Science.gov (United States)

    Yao, Guangbao; Li, Jiang; Chao, Jie; Pei, Hao; Liu, Huajie; Zhao, Yun; Shi, Jiye; Huang, Qing; Wang, Lianhui; Huang, Wei; Fan, Chunhai

    2015-03-02

    DNA origami has rapidly emerged as a powerful and programmable method to construct functional nanostructures. However, the size limitation of approximately 100 nm in classic DNA origami hampers its plasmonic applications. Herein, we report a jigsaw-puzzle-like assembly strategy mediated by gold nanoparticles (AuNPs) to break the size limitation of DNA origami. We demonstrated that oligonucleotide-functionalized AuNPs function as universal joint units for the one-pot assembly of parent DNA origami of triangular shape to form sub-microscale super-origami nanostructures. AuNPs anchored at predefined positions of the super-origami exhibited strong interparticle plasmonic coupling. This AuNP-mediated strategy offers new opportunities to drive macroscopic self-assembly and to fabricate well-defined nanophotonic materials and devices. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Shear Modulus of Sintered 'House of Cards'-Like Assemblies of Crystals

    NARCIS (Netherlands)

    Schaink, H.M.; Malssen, van K.

    2007-01-01

    A cell model of a 'house of cards'-like assembly of crystals is used for the study of the evolution of the shear modulus during sintering. The crystals are assumed to have a lozenge shape. The cell model takes different crystal-crystal contacts into account. The force needed to separate two sintered

  14. Matrix metalloproteases and tissue inhibitors of metalloproteinases in medial plica and pannus-like tissue contribute to knee osteoarthritis progression.

    Science.gov (United States)

    Yang, Chih-Chang; Lin, Cheng-Yu; Wang, Hwai-Shi; Lyu, Shaw-Ruey

    2013-01-01

    Osteoarthritis (OA) is characterized by degradation of the cartilage matrix, leading to pathologic changes in the joints. However, the pathogenic effects of synovial tissue inflammation on OA knees are not clear. To investigate whether the inflammation caused by the medial plica is involved in the pathogenesis of osteoarthritis, we examined the expression of matrix metalloproteinases (MMPs), tissue inhibitors of metalloproteinases (TIMPs), interleukin (IL)-1β, and tumor necrosis factor (TNF)-α in the medial plica and pannus-like tissue in the knees of patients with medial compartment OA who underwent either arthroscopic medial release (stage II; 15 knee joints from 15 patients) or total knee replacement (stage IV; 18 knee joints from 18 patients). MMP-2, MMP-3, MMP-9, IL-1β, and TNF-α mRNA and protein levels measured, respectively, by quantitative real-time PCR and Quantibody human MMP arrays, were highly expressed in extracts of medial plica and pannus-like tissue from stage IV knee joints. Immunohistochemical staining also demonstrated high expression of MMP-2, MMP-3, and MMP-9 in plica and pannus-like tissue of stage IV OA knees and not in normal cartilage. Some TIMP/MMP ratios decreased significantly in both medial plica and pannus-like tissue as disease progressed from stage II to stage IV. Furthermore, the migration of cells from the pannus-like tissue was enhanced by IL-1β, while plica cell migration was enhanced by TNF-α. The results suggest that medial plica and pannus-like tissue may be involved in the process of cartilage degradation in medial compartment OA of the knee.

  15. Matrix metalloproteases and tissue inhibitors of metalloproteinases in medial plica and pannus-like tissue contribute to knee osteoarthritis progression.

    Directory of Open Access Journals (Sweden)

    Chih-Chang Yang

    Full Text Available Osteoarthritis (OA is characterized by degradation of the cartilage matrix, leading to pathologic changes in the joints. However, the pathogenic effects of synovial tissue inflammation on OA knees are not clear. To investigate whether the inflammation caused by the medial plica is involved in the pathogenesis of osteoarthritis, we examined the expression of matrix metalloproteinases (MMPs, tissue inhibitors of metalloproteinases (TIMPs, interleukin (IL-1β, and tumor necrosis factor (TNF-α in the medial plica and pannus-like tissue in the knees of patients with medial compartment OA who underwent either arthroscopic medial release (stage II; 15 knee joints from 15 patients or total knee replacement (stage IV; 18 knee joints from 18 patients. MMP-2, MMP-3, MMP-9, IL-1β, and TNF-α mRNA and protein levels measured, respectively, by quantitative real-time PCR and Quantibody human MMP arrays, were highly expressed in extracts of medial plica and pannus-like tissue from stage IV knee joints. Immunohistochemical staining also demonstrated high expression of MMP-2, MMP-3, and MMP-9 in plica and pannus-like tissue of stage IV OA knees and not in normal cartilage. Some TIMP/MMP ratios decreased significantly in both medial plica and pannus-like tissue as disease progressed from stage II to stage IV. Furthermore, the migration of cells from the pannus-like tissue was enhanced by IL-1β, while plica cell migration was enhanced by TNF-α. The results suggest that medial plica and pannus-like tissue may be involved in the process of cartilage degradation in medial compartment OA of the knee.

  16. Diagnostic radiopharmaceuticals for localization in target tissues exhibiting a regional pH shift relative to surrounding tissues

    International Nuclear Information System (INIS)

    Blau, M.; Kung, H.F.

    1985-01-01

    Diagnostic radiopharmaceutical compounds are provided which are capable of entering a target tissue or a target organ by passive diffusion through cell walls and which are effectively accumulated and retained within the target tissue or organ due to a regional pH shift. Such compounds are desirably readily accessible synthetically using readily available radionuclides. The compound comprises a radioactive isotope of an element in chemical combination with at least one amine group and preferably with at least two secondary or tertiary amine groups. The radioactive element is an element other than iodine emitting gamma ray, x-ray or positron radiation. When the element is a gamma ray emitting isotope, at least 75 percent of the number of emissions is emitted at energies of between 80 and 400 keV. The half-life of the isotope is usually between two minutes and 15 days. The compound has acid-base characteristics such that the state of ionization of the compound at the pH of the body is significantly different and usually less than its state of ionization at the intracellular pH of the target tissue. The compound has such lipid solubility characteristics that it is capable of ready penetration through cell walls, but within cells its lipid solubility is substantially decreased, whereby the ability of the compound to leave the target tissue is substantially diminished. Specific data relevant to di-beta-(piperidinoethyl)-selenide and di-beta-(morpholinoethyl)-selenide in rat brains are presented

  17. Mapsembler, targeted and micro assembly of large NGS datasets on a desktop computer

    Directory of Open Access Journals (Sweden)

    Peterlongo Pierre

    2012-03-01

    Full Text Available Abstract Background The analysis of next-generation sequencing data from large genomes is a timely research topic. Sequencers are producing billions of short sequence fragments from newly sequenced organisms. Computational methods for reconstructing whole genomes/transcriptomes (de novo assemblers are typically employed to process such data. However, these methods require large memory resources and computation time. Many basic biological questions could be answered targeting specific information in the reads, thus avoiding complete assembly. Results We present Mapsembler, an iterative micro and targeted assembler which processes large datasets of reads on commodity hardware. Mapsembler checks for the presence of given regions of interest that can be constructed from reads and builds a short assembly around it, either as a plain sequence or as a graph, showing contextual structure. We introduce new algorithms to retrieve approximate occurrences of a sequence from reads and construct an extension graph. Among other results presented in this paper, Mapsembler enabled to retrieve previously described human breast cancer candidate fusion genes, and to detect new ones not previously known. Conclusions Mapsembler is the first software that enables de novo discovery around a region of interest of repeats, SNPs, exon skipping, gene fusion, as well as other structural events, directly from raw sequencing reads. As indexing is localized, the memory footprint of Mapsembler is negligible. Mapsembler is released under the CeCILL license and can be freely downloaded from http://alcovna.genouest.org/mapsembler/.

  18. 3D bio-etching of a complex composite-like embryonic tissue.

    Science.gov (United States)

    Hazar, Melis; Kim, Yong Tae; Song, Jiho; LeDuc, Philip R; Davidson, Lance A; Messner, William C

    2015-08-21

    Morphogenesis involves a complex series of cell signaling, migration and differentiation events that are coordinated as tissues self-assemble during embryonic development. Collective cell movements such as those that occur during morphogenesis have typically been studied in 2D with single layers of cultured cells adhering to rigid substrates such as glass or plastic. In vivo, the intricacies of the 3D microenvironment and complex 3D responses are pivotal in the formation of functional tissues. To study such processes as collective cell movements within 3D multilayered tissues, we developed a microfluidic technique capable of producing complex 3D laminar multicellular structures. We call this technique "3D tissue-etching" because it is analogous to techniques used in the microelectromechanics (MEMS) field where complex 3D structures are built by successively removing material from a monolithic solid through subtractive manufacturing. We use a custom-designed microfluidic control system to deliver a range of tissue etching reagents (detergents, chelators, proteases, etc.) to specific regions of multilayered tissues. These tissues were previously isolated by microsurgical excision from embryos of the African claw-toed frog, Xenopus laevis. The ability to shape the 3D form of multicellular tissues and to control 3D stimulation will have a high impact on tissue engineering and regeneration applications in bioengineering and medicine as well as provide significant improvements in the synthesis of highly complex 3D integrated multicellular biosystems.

  19. Toughening of Thermoresponsive Arrested Networks of Elastin-Like Polypeptides To Engineer Cytocompatible Tissue Scaffolds.

    Science.gov (United States)

    Glassman, Matthew J; Avery, Reginald K; Khademhosseini, Ali; Olsen, Bradley D

    2016-02-08

    Formulation of tissue engineering or regenerative scaffolds from simple bioactive polymers with tunable structure and mechanics is crucial for the regeneration of complex tissues, and hydrogels from recombinant proteins, such as elastin-like polypeptides (ELPs), are promising platforms to support these applications. The arrested phase separation of ELPs has been shown to yield remarkably stiff, biocontinuous, nanostructured networks, but these gels are limited in applications by their relatively brittle nature. Here, a gel-forming ELP is chain-extended by telechelic oxidative coupling, forming extensible, tough hydrogels. Small angle scattering indicates that the chain-extended polypeptides form a fractal network of nanoscale aggregates over a broad concentration range, accessing moduli ranging from 5 kPa to over 1 MPa over a concentration range of 5-30 wt %. These networks exhibited excellent erosion resistance and allowed for the diffusion and release of encapsulated particles consistent with a bicontinuous, porous structure with a broad distribution of pore sizes. Biofunctionalized, toughened networks were found to maintain the viability of human mesenchymal stem cells (hMSCs) in 2D, demonstrating signs of osteogenesis even in cell media without osteogenic molecules. Furthermore, chondrocytes could be readily mixed into these gels via thermoresponsive assembly and remained viable in extended culture. These studies demonstrate the ability to engineer ELP-based arrested physical networks on the molecular level to form reinforced, cytocompatible hydrogel matrices, supporting the promise of these new materials as candidates for the engineering and regeneration of stiff tissues.

  20. Stability and assembly in vitro of bacteriophage PP7 virus-like particles

    Directory of Open Access Journals (Sweden)

    Peabody David S

    2007-11-01

    Full Text Available Abstract Background The stability of a virus-like particle (VLP is an important consideration for its use in nanobiotechnology. The icosahedral capsid of the RNA bacteriophage PP7 is cross-linked by disulfide bonds between coat protein dimers at its 5-fold and quasi-6-fold symmetry axes. This work determined the effects of these disulfides on the VLP's thermal stability. Results Measurements of the thermal denaturation behavior of PP7 VLPs in the presence and absence of a reducing agent show that disulfide cross-links substantially stabilize them against thermal denaturation. Although dimers in the capsid are linked to one another by disulfides, the two subunits of dimers themselves are held together only by non-covalent interactions. In an effort to confer even greater stability a new cross-link was introduced by genetically fusing two coat protein monomers, thus producing a "single-chain dimer" that assembles normally into a completely cross-linked VLP. However, subunit fusion failed to increase the thermal stability of the particles, even though it stabilized the isolated dimer. As a step toward gaining control of the internal composition of the capsid, conditions that promote the assembly of PP7 coat protein dimers into virus-like particles in vitro were established. Conclusion The presence of inter-dimer disulfide bonds greatly stabilizes the PP7 virus-like particle against thermal denaturation. Covalently cross-linking the subunits of the dimers themselves by genetically fusing them through a dipeptide linker sequence, offers no further stabilization of the VLP, although it does stabilize the dimer. PP7 capsids readily assemble in vitro in a reaction that requires RNA.

  1. Disulfide-induced self-assembled targets: A novel strategy for the label free colorimetric detection of DNAs/RNAs via unmodified gold nanoparticles

    Science.gov (United States)

    Shokri, Ehsan; Hosseini, Morteza; Davari, Mehdi D.; Ganjali, Mohammad R.; Peppelenbosch, Maikel P.; Rezaee, Farhad

    2017-04-01

    A modified non-cross-linking gold-nanoparticles (Au-NPs) aggregation strategy has been developed for the label free colorimetric detection of DNAs/RNAs based on self-assembling target species in the presence of thiolated probes. Two complementary thiol- modified probes, each of which specifically binds at one half of the target introduced SH groups at both ends of dsDNA. Continuous disulfide bond formation at 3‧ and 5‧ terminals of targets leads to the self-assembly of dsDNAs into the sulfur- rich and flexible products with different lengths. These products have a high affinity for the surface of Au-NPs and efficiently protect the surface from salt induced aggregation. To evaluate the assay efficacy, a small part of the citrus tristeza virus (CTV) genome was targeted, leading to a detection limit of about 5 × 10-9 mol.L-1 over a linear ranged from 20 × 10-9 to 10 × 10-7 mol.L-1. This approach also exhibits good reproducibility and recovery levels in the presence of plant total RNA or human plasma total circulating RNA extracts. Self-assembled targets can be then sensitively distinguished from non-assembled or mismatched targets after gel electrophoresis. The disulfide reaction method and integrating self-assembled DNAs/RNAs targets with bare AuNPs as a sensitive indicator provide us a powerful and simple visual detection tool for a wide range of applications.

  2. The Vascular Niche in Tissue Repair: A Therapeutic Target for Regeneration

    OpenAIRE

    Rivera, Francisco J.; Silva, Maria Elena; Aigner, Ludwig

    2017-01-01

    Editorial on the Research Topic The Vascular Niche in Tissue Repair: A Therapeutic Target for Regeneration In mammals, although regeneration is quite restricted to a number of tissues and organs, this particular healing process is possible through the existence of tissue-resident stem/progenitor cells. Upon injury, these cells are activated, they proliferate, migrate, and differentiate into tissue-specific cells and functionally replace the damaged or lost cells. Besides this, angio...

  3. Cellular imaging by targeted assembly of hot-spot SERS and photoacoustic nanoprobes using split-fluorescent protein scaffolds.

    Science.gov (United States)

    Köker, Tuğba; Tang, Nathalie; Tian, Chao; Zhang, Wei; Wang, Xueding; Martel, Richard; Pinaud, Fabien

    2018-02-09

    The in cellulo assembly of plasmonic nanomaterials into photo-responsive probes is of great interest for many bioimaging and nanophotonic applications but remains challenging with traditional nucleic acid scaffolds-based bottom-up methods. Here, we address this quandary using split-fluorescent protein (FP) fragments as molecular glue and switchable Raman reporters to assemble gold or silver plasmonic nanoparticles (NPs) into photonic clusters directly in live cells. When targeted to diffusing surface biomarkers in cancer cells, the NPs self-assemble into surface-enhanced Raman-scattering (SERS) nanoclusters having hot spots homogenously seeded by the reconstruction of full-length FPs. Within plasmonic hot spots, autocatalytic activation of the FP chromophore and near-field amplification of its Raman fingerprints enable selective and sensitive SERS imaging of targeted cells. This FP-driven assembly of metal colloids also yields enhanced photoacoustic signals, allowing the hybrid FP/NP nanoclusters to serve as contrast agents for multimodal SERS and photoacoustic microscopy with single-cell sensitivity.

  4. Accelerated Development of Supramolecular Corneal Stromal-Like Assemblies from Corneal Fibroblasts in the Presence of Macromolecular Crowders.

    Science.gov (United States)

    Kumar, Pramod; Satyam, Abhigyan; Fan, Xingliang; Rochev, Yury; Rodriguez, Brian J; Gorelov, Alexander; Joshi, Lokesh; Raghunath, Michael; Pandit, Abhay; Zeugolis, Dimitrios I

    2015-07-01

    Tissue engineering by self-assembly uses the cells' secretome as a regeneration template and biological factory of trophic factors. Despite the several advantages that have been witnessed in preclinical and clinical settings, the major obstacle for wide acceptance of this technology remains the tardy extracellular matrix formation. In this study, we assessed the influence of macromolecular crowding (MMC)/excluding volume effect, a biophysical phenomenon that accelerates thermodynamic activities and biological processes by several orders of magnitude, in human corneal fibroblast (HCF) culture. Our data indicate that the addition of negatively charged galactose derivative (carrageenan) in HCF culture, even at 0.5% serum, increases by 12-fold tissue-specific matrix deposition, while maintaining physiological cell morphology and protein/gene expression. Gene analysis indicates that a glucose derivative (dextran sulfate) may drive corneal fibroblasts toward a myofibroblast lineage. Collectively, these results indicate that MMC may be suitable not only for clinical translation and commercialization of tissue engineering by self-assembly therapies, but also for the development of in vitro pathophysiology models.

  5. Transplantation of Xenopus laevis tissues to determine the ability of motor neurons to acquire a novel target.

    Directory of Open Access Journals (Sweden)

    Karen L Elliott

    Full Text Available The evolutionary origin of novelties is a central problem in biology. At a cellular level this requires, for example, molecularly resolving how brainstem motor neurons change their innervation target from muscle fibers (branchial motor neurons to neural crest-derived ganglia (visceral motor neurons or ear-derived hair cells (inner ear and lateral line efferent neurons. Transplantation of various tissues into the path of motor neuron axons could determine the ability of any motor neuron to innervate a novel target. Several tissues that receive direct, indirect, or no motor innervation were transplanted into the path of different motor neuron populations in Xenopus laevis embryos. Ears, somites, hearts, and lungs were transplanted to the orbit, replacing the eye. Jaw and eye muscle were transplanted to the trunk, replacing a somite. Applications of lipophilic dyes and immunohistochemistry to reveal motor neuron axon terminals were used. The ear, but not somite-derived muscle, heart, or liver, received motor neuron axons via the oculomotor or trochlear nerves. Somite-derived muscle tissue was innervated, likely by the hypoglossal nerve, when replacing the ear. In contrast to our previous report on ear innervation by spinal motor neurons, none of the tissues (eye or jaw muscle was innervated when transplanted to the trunk. Taken together, these results suggest that there is some plasticity inherent to motor innervation, but not every motor neuron can become an efferent to any target that normally receives motor input. The only tissue among our samples that can be innervated by all motor neurons tested is the ear. We suggest some possible, testable molecular suggestions for this apparent uniqueness.

  6. In vitro characterization of self-assembled anterior cruciate ligament cell spheroids for ligament tissue engineering.

    Science.gov (United States)

    Hoyer, M; Meier, C; Breier, A; Hahner, J; Heinrich, G; Drechsel, N; Meyer, M; Rentsch, C; Garbe, L-A; Ertel, W; Lohan, A; Schulze-Tanzil, G

    2015-03-01

    Tissue engineering of an anterior cruciate ligament (ACL) implant with functional enthesis requires site-directed seeding of different cell types on the same scaffold. Therefore, we studied the suitability of self-assembled three-dimensional spheroids generated by lapine ACL ligament fibroblasts for directed scaffold colonization. The spheroids were characterized in vitro during 14 days in static and 7 days in dynamic culture. Size maintenance of self-assembled spheroids, the vitality, the morphology and the expression pattern of the cells were monitored. Additionally, we analyzed the total sulfated glycosaminoglycan, collagen contents and the expression of the ligament components type I collagen, decorin and tenascin C on protein and for COL1A1, DCN and TNMD on gene level in the spheroids. Subsequently, the cell colonization of polylactide-co-caprolactone [P(LA-CL)] and polydioxanone (PDS) polymer scaffolds was assessed in response to a directed, spheroid-based seeding technique. ACL cells were able to self-assemble spheroids and survive over 14 days. The spheroids decreased in size but not in cellularity depending on the culture time and maintained or even increased their differentiation state. The area of P[LA-CL] scaffolds, colonized after 14 days by the cells of one spheroid, was in average 4.57 ± 2.3 mm(2). Scaffolds consisting of the polymer P[LA-CL] were more suitable for colonization by spheroids than PDS embroideries. We conclude that ACL cell spheroids are suitable as site-directed seeding strategy for scaffolds in ACL tissue engineering approaches and recommend the use of freshly assembled spheroids for scaffold colonization, due to their balanced proliferation and differentiation.

  7. Expression of protein-tyrosine phosphatases in the major insulin target tissues

    DEFF Research Database (Denmark)

    Norris, K; Norris, F; Kono, D H

    1997-01-01

    Protein-tyrosine phosphatases (PTPs) are key regulators of the insulin receptor signal transduction pathway. We have performed a detailed analysis of PTP expression in the major human insulin target tissues or cells (liver, adipose tissue, skeletal muscle and endothelial cells). To obtain a repre...

  8. In vitro assembly of Ebola virus nucleocapsid-like complex expressed in E. coli

    Directory of Open Access Journals (Sweden)

    Ruchao Peng

    2016-09-01

    Full Text Available Abstract Ebola virus (EBOV harbors an RNA genome encapsidated by nucleoprotein (NP along with other viral proteins to form a nucleocapsid complex. Previous Cryo-eletron tomography and biochemical studies have shown the helical structure of EBOV nucleocapsid at nanometer resolution and the first 450 amino-acid of NP (NPΔ451–739 alone is capable of forming a helical nucleocapsid-like complex (NLC. However, the structural basis for NP-NP interaction and the dynamic procedure of the nucleocapsid assembly is yet poorly understood. In this work, we, by using an E. coli expression system, captured a series of images of NPΔ451–739 conformers at different stages of NLC assembly by negative-stain electron microscopy, which allowed us to picture the dynamic procedure of EBOV nucleocapsid assembly. Along with further biochemical studies, we showed the assembly of NLC is salt-sensitive, and also established an indispensible role of RNA in this process. We propose the diverse modes of NLC elongation might be the key determinants shaping the plasticity of EBOV virions. Our findings provide a new model for characterizing the self-oligomerization of viral nucleoproteins and studying the dynamic assembly process of viral nucleocapsid in vitro.

  9. Fabrication of bone marrow-like tissue in vitro from dispersed-state bone marrow cells

    Directory of Open Access Journals (Sweden)

    Kanae Sayo

    2016-03-01

    Full Text Available A three-dimensional (3D bone marrow (BM culture system may facilitate research into the molecular mechanisms involved in hematopoiesis and BM diseases. However, because >90% of BM cells are composed of non-adherent blood cells, it is difficult to organize the dispersed BM cells into 3D multicellular spheroids using conventional aggregation methods such as hanging drop, and rotary shaking culture. The objective of this study was to reproduce BM-like tissue. We reported successful formation of BM aggregates using a 3% methylcellulose (MC medium. This medium could aggregate even non-adherent materials. In MC medium, BM cells formed tissue-like aggregates within 24 h. Although the cell density of the BM-like tissue is slightly low, sections of the organoids resembled those of intact BM tissue. Cells of the BM-like tissue were approximately 70% viable after 7 days in culture. Staining for CD68, PDGFRα, and CXCL12 indicated that the BM-like tissue contained macrophages, and mesenchymal cells including CXCL12-abundant reticular cells. These results indicated that the method using MC medium effectively reconstitutes the BM-like tissue.

  10. Development of Three-Dimensional Multicellular Tissue-Like Constructs for Mutational Analysis Using Macroporous Microcarriers

    Science.gov (United States)

    Jordan, Jacqueline A.; Fraga, Denise N.; Gonda, Steve R.

    2002-01-01

    A three-dimensional (3-D), tissue-like model was developed for the genotoxic assessment of space environment. In previous experiments, we found that culturing mammalian cells in a NASA-designed bioreactor, using Cytodex-3 beads as a scaffold, generated 3-D multicellular spheroids. In an effort to generate scaffold-free spheroids, we developed a new 3-D tissue-like model by coculturing fibroblast and epithelial cell in a NASA bioreactor using macroporous Cultispher-S(TradeMark) microcarriers. Big Blue(Registered Trademark) Rat 2(Lambda) fibroblasts, genetically engineered to contain multiple copies (>60 copies/cell) of the Lac I target gene, were cocultured with radio-sensitive human epithelial cells, H184F5. Over an 8-day period, samples were periodically examined by microscopy and histology to confirm cell attachment, growth, and viability. Immunohistochemistry and western analysis were used to evaluate the expression of specific cytoskeletal and adhesion proteins. Key cell culture parameters (glucose, pH, and lactate concentrations) were monitored daily. Controls were two-dimensional mono layers of fibroblast or epithelial cells cultured in T-flasks. Analysis of 3-D spheroids from the bioreactor suggests fibroblast cells attached to and completely covered the bead surface and inner channels by day 3 in the bioreactor. Treatment of the 3-day spheroids with dispase II dissolved the Cultisphers(TradeMark) and produced multicellular, bead-less constructs. Immunohistochemistry confirmed the presence of vi.mentin, cytokeratin and E-cadherin in treated spheroids. Examination of the dispase II treated spheroids with transmission electron microscopy (TEM) also showed the presence of desmosomes. These results suggest that the controlled enzymatic degradation of an artificial matrix in the low shear environment of the NASA-designed bioreactor can produce 3-D tissue-like spheroids. 2

  11. Hierarchically assembled Au microspheres and sea urchin-like architectures: formation mechanism and SERS study.

    Science.gov (United States)

    Wang, Xiansong; Yang, Da-Peng; Huang, Peng; Li, Min; Li, Chao; Chen, Di; Cui, Daxiang

    2012-12-21

    The hierarchically assembled Au microspheres/sea urchin-like structures have been synthesized in aqueous solution at room temperature with and without proteins (bovine serum albumin, BSA) as mediators. The average diameter of an individual Au microsphere is 300-600 nm, which is composed of some compact nanoparticles with an average diameter of about 15 nm. Meanwhile, the sea urchin-like Au architecture exhibits an average diameter of 600-800 nm, which is made up of some nanopricks with an average length of 100-200 nm. These products are characterized by means of scanning electron microscopy (SEM), X-ray diffraction (XRD) and transmission electronic microscopy (TEM). It is found that the BSA and ascorbic acid (AA) have great effects on the morphology of the resulting products. Two different growth mechanisms are proposed. The study on surface enhanced Raman scattering (SERS) activities is also carried out between Au microspheres and Au sea urchin-like architectures. It is found that Au urchin-like architectures possess much higher SERS activity than the Au microspheres. Our work may shed light on the design and synthesis of hierarchically self-assembled 3D micro/nano-architectures for SERS, catalysis and biosensors.

  12. Desmosome Assembly and Disassembly Are Membrane Raft-Dependent

    Science.gov (United States)

    Faundez, Victor; Koval, Michael; Mattheyses, Alexa L.; Kowalczyk, Andrew P.

    2014-01-01

    Strong intercellular adhesion is critical for tissues that experience mechanical stress, such as the skin and heart. Desmosomes provide adhesive strength to tissues by anchoring desmosomal cadherins of neighboring cells to the intermediate filament cytoskeleton. Alterations in assembly and disassembly compromise desmosome function and may contribute to human diseases, such as the autoimmune skin blistering disease pemphigus vulgaris (PV). We previously demonstrated that PV auto-antibodies directed against the desmosomal cadherin desmoglein 3 (Dsg3) cause loss of adhesion by triggering membrane raft-mediated Dsg3 endocytosis. We hypothesized that raft membrane microdomains play a broader role in desmosome homeostasis by regulating the dynamics of desmosome assembly and disassembly. In human keratinocytes, Dsg3 is raft associated as determined by biochemical and super resolution immunofluorescence microscopy methods. Cholesterol depletion, which disrupts rafts, prevented desmosome assembly and adhesion, thus functionally linking rafts to desmosome formation. Interestingly, Dsg3 did not associate with rafts in cells lacking desmosomal proteins. Additionally, PV IgG-induced desmosome disassembly occurred by redistribution of Dsg3 into raft-containing endocytic membrane domains, resulting in cholesterol-dependent loss of adhesion. These findings demonstrate that membrane rafts are required for desmosome assembly and disassembly dynamics, suggesting therapeutic potential for raft targeting agents in desmosomal diseases such as PV. PMID:24498201

  13. Dysregulated homeostasis of target tissues or autoantigens - A novel principle in autoimmunity.

    Science.gov (United States)

    Petersen, Frank; Yue, Xiaoyang; Riemekasten, Gabriela; Yu, Xinhua

    2017-06-01

    Monogenic autoimmune disorders provide a powerful tool for our understanding of the principles of autoimmunity due to the obvious impact of a single gene on the disease. So far, approximately 100 single gene defects causing murine monogenic autoimmune disorders have been reported and the functional characterization of these genes will provide significant progress in understanding the nature of autoimmunity. According to their function, genes leading to monogenic autoimmune disorders can be categorized into two groups. An expectable first group contains genes involved in the homeostasis of the immune system, including homeostasis of immune organs and immune cells. Intriguingly, the second group consists of genes functionally involved in the homeostasis of target tissues or autoantigens. According to our novel hypothesis, we propose that autoimmunity represents a consequence of a dysregulated homeostasis of the immune system and/or its targets including autoantigens and target tissues. In this review we refer to both aspects of homeostasis in autoimmunity with a highlight on the role of the homeostasis of target tissues and autoantigens. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Self-assembly of a superparamagnetic raspberry-like silica/iron oxide nanocomposite using epoxy-amine coupling chemistry.

    Science.gov (United States)

    Cano, Manuel; de la Cueva-Méndez, Guillermo

    2015-02-28

    The fabrication of colloidal nanocomposites would benefit from controlled hetero-assembly of ready-made particles through covalent bonding. Here we used epoxy-amine coupling chemistry to promote the self-assembly of superparamagnetic raspberry-like nanocomposites. This adaptable method induced the covalent attachment of iron oxide nanoparticles sparsely coated with amine groups onto epoxylated silica cores in the absence of other reactants.

  15. Polymorphisms in the human tropoelastin gene modify in vitro self-assembly and mechanical properties of elastin-like polypeptides.

    Directory of Open Access Journals (Sweden)

    David He

    Full Text Available Elastin is a major structural component of elastic fibres that provide properties of stretch and recoil to tissues such as arteries, lung and skin. Remarkably, after initial deposition of elastin there is normally no subsequent turnover of this protein over the course of a lifetime. Consequently, elastic fibres must be extremely durable, able to withstand, for example in the human thoracic aorta, billions of cycles of stretch and recoil without mechanical failure. Major defects in the elastin gene (ELN are associated with a number of disorders including Supravalvular aortic stenosis (SVAS, Williams-Beuren syndrome (WBS and autosomal dominant cutis laxa (ADCL. Given the low turnover of elastin and the requirement for the long term durability of elastic fibres, we examined the possibility for more subtle polymorphisms in the human elastin gene to impact the assembly and long-term durability of the elastic matrix. Surveys of genetic variation resources identified 118 mutations in human ELN, 17 being non-synonymous. Introduction of two of these variants, G422S and K463R, in elastin-like polypeptides as well as full-length tropoelastin, resulted in changes in both their assembly and mechanical properties. Most notably G422S, which occurs in up to 40% of European populations, was found to enhance some elastomeric properties. These studies reveal that even apparently minor polymorphisms in human ELN can impact the assembly and mechanical properties of the elastic matrix, effects that over the course of a lifetime could result in altered susceptibility to cardiovascular disease.

  16. Localized increase of tissue oxygen tension by magnetic targeted drug delivery

    Science.gov (United States)

    Liong, Celine; Ortiz, Daniel; Ao-ieong, Eilleen; Navati, Mahantesh S.; Friedman, Joel M.; Cabrales, Pedro

    2014-07-01

    Hypoxia is the major hindrance to successful radiation therapy of tumors. Attempts to increase the oxygen (O2) tension (PO2) of tissue by delivering more O2 have been clinically disappointing, largely due to the way O2 is transported and released by the hemoglobin (Hb) within the red blood cells (RBCs). Systemic manipulation of O2 transport increases vascular resistance due to metabolic autoregulation of blood flow to prevent over oxygenation. This study investigates a new technology to increase O2 delivery to a target tissue by decreasing the Hb-O2 affinity of the blood circulating within the targeted tissue. As the Hb-O2 affinity decreases, the tissue PO2 to satisfy tissue O2 metabolic needs increases without increasing O2 delivery or extraction. Paramagnetic nanoparticles (PMNPs), synthetized using gadolinium oxide, were coated with the cell permeable Hb allosteric effector L35 (3,5-trichlorophenylureido-phenoxy-methylpropionic acid). L35 decreases Hb affinity for O2 and favors the release of O2. The L35-coated PMNPs (L35-PMNPs) were intravenously infused (10 mg kg-1) to hamsters instrumented with the dorsal window chamber model. A magnetic field of 3 mT was applied to localize the effects of the L35-PMNPs to the window chamber. Systemic O2 transport characteristics and microvascular tissue oxygenation were measured after administration of L35-PMNPs with and without magnetic field. The tissue PO2 in untreated control animals was 25.2 mmHg. L35-PMNPs without magnetic field decreased tissue PO2 to 23.4 mmHg, increased blood pressure, and reduced blood flow, largely due to systemic modification of Hb-O2 affinity. L35-PMNPs with magnetic field increased tissue PO2 to 27.9 mmHg, without systemic or microhemodynamic changes. These results indicate that localized modification of Hb-O2 affinity can increase PO2 of target tissue without affecting systemic O2 delivery or triggering O2 autoregulation mechanisms. This technology can be used to treat local hypoxia and to

  17. Hyper bio assembler for 3D cellular systems

    CERN Document Server

    Arai, Fumihito; Yamato, Masayuki

    2015-01-01

    Hyper Bio Assembler for Cellular Systems is the first book to present a new methodology for measuring and separating target cells at high speed and constructing 3D cellular systems in vitro. This book represents a valuable resource for biologists, biophysicists and robotic engineers, as well as researchers interested in this new frontier area, offering a better understanding of the measurement, separation, assembly, analysis and synthesis of complex biological tissue, and of the medical applications of these technologies. This book is the outcome of the new academic fields of the Ministry of Education, Culture, Sports, Science and Technology’s Grant-in-Aid for Scientific Research in Japan.

  18. TOLL-LIKE RECEPTORS IN FAT BODY AND SALIVARY GLAND TISSUES IN THE CATTLE TICK Rhipicephalus microplus

    Directory of Open Access Journals (Sweden)

    Sabrina Rita da Fonseca Rezende

    2016-11-01

    Full Text Available ABSTRACT. Rezende S.deF., Fontenele M.R., Masuda C.A., de Oliveira P.L., Araujo H.M.M., Bittencourt V.R.E.P. & Leite M.de S. Toll-like receptors in fat body and salivary gland tissues in the cattle tick Rhipicephalus microplus. [Receptores Toll-like em corpo gorduroso e glândula salivar do carrapato bovino Rhipicephalus microplus]. Revista Brasileira de Medicina Veterinária, 38(supl. 3:47-53, 2016. Programa de Pós-Graduação em Ciências Veterinárias, Anexo 1, Instituto de Veterinária, Universidade Federal Rural do Estado do Rio de Janeiro, BR 465, KM 47, Seropédica, RJ 23890-000, Brasil. E-mail: milaneleite@ufrrj.br Toll-like receptors (TLRs play an important role in the recognition of pathogen components and subsequent activation of the innate immune response, which then leads to development of immune responses. In arthropods the fat body and salivary glands are important organs in the defense system against invading pathogens. In this study, we identified for the first time the presence of TLRs in fat body and salivary gland tissues of cattle tick Rhipicephalus microplus. Our results show that the expression of TLRs in fat body tissue are not found in all cells, but is specific to some cell types, in salivary glands TLRs protein expression occur in acini structure. We suggest that immune pathways are active in both fat body and salivary glands in the tick. The potential use of TLRs as a target for vaccine formulations against is discussed.

  19. The influence of ligand charge and length on the assembly of Brome mosaic virus derived virus-like particles with magnetic core

    Science.gov (United States)

    Mieloch, Adam A.; Krecisz, Monika; Rybka, Jakub D.; Strugała, Aleksander; Krupiński, Michał; Urbanowicz, Anna; Kozak, Maciej; Skalski, Bohdan; Figlerowicz, Marek; Giersig, Michael

    2018-03-01

    Virus-like particles (VLPs) have sparked a great interest in the field of nanobiotechnology and nanomedicine. The introduction of superparamagnetic nanoparticles (SPIONs) as a core, provides potential use of VLPs in the hyperthermia therapy, MRI contrast agents and magnetically-powered delivery agents. Magnetite NPs also provide a significant improvement in terms of VLPs stability. Moreover employing viral structural proteins as self-assembling units has opened a new paths for targeted therapy, drug delivery systems, vaccines design, and many more. In many cases, the self-assembly of a virus strongly depends on electrostatic interactions between positively charged groups of the capsid proteins and negatively charged nucleic acid. This phenomenon imposes the negative net charge as a key requirement for the core nanoparticle. In our experiments, Brome mosaic virus (BMV) capsid proteins isolated from infected plants Hordeum vulgare were used. Superparamagnetic iron oxide nanoparticles (Fe3O4) with 15 nm in diameter were synthesized by thermal decomposition and functionalized with COOH-PEG-PL polymer or dihexadecylphosphate (DHP) in order to provide water solubility and negative charge required for the assembly. Nanoparticles were characterized by Transmission Electron Microscopy (TEM), Dynamic Light Scattering (DLS), Zeta Potential, Fourier Transformed Infrared Spectroscopy (FTIR) and Superconducting Quantum Interference Device (SQUID) magnetometry. TEM and DLS study were conducted to verify VLPs creation. This study demonstrates that the increase of negative surface charge is not a sufficient factor determining successful assembly. Additional steric interactions provided by longer ligands are crucial for the assembly of BMV SPION VLPs and may enhance the colloidal stability.

  20. The influence of ligand charge and length on the assembly of Brome mosaic virus derived virus-like particles with magnetic core

    Directory of Open Access Journals (Sweden)

    Adam A. Mieloch

    2018-03-01

    Full Text Available Virus-like particles (VLPs have sparked a great interest in the field of nanobiotechnology and nanomedicine. The introduction of superparamagnetic nanoparticles (SPIONs as a core, provides potential use of VLPs in the hyperthermia therapy, MRI contrast agents and magnetically-powered delivery agents. Magnetite NPs also provide a significant improvement in terms of VLPs stability. Moreover employing viral structural proteins as self-assembling units has opened a new paths for targeted therapy, drug delivery systems, vaccines design, and many more. In many cases, the self-assembly of a virus strongly depends on electrostatic interactions between positively charged groups of the capsid proteins and negatively charged nucleic acid. This phenomenon imposes the negative net charge as a key requirement for the core nanoparticle. In our experiments, Brome mosaic virus (BMV capsid proteins isolated from infected plants Hordeum vulgare were used. Superparamagnetic iron oxide nanoparticles (Fe3O4 with 15 nm in diameter were synthesized by thermal decomposition and functionalized with COOH-PEG-PL polymer or dihexadecylphosphate (DHP in order to provide water solubility and negative charge required for the assembly. Nanoparticles were characterized by Transmission Electron Microscopy (TEM, Dynamic Light Scattering (DLS, Zeta Potential, Fourier Transformed Infrared Spectroscopy (FTIR and Superconducting Quantum Interference Device (SQUID magnetometry. TEM and DLS study were conducted to verify VLPs creation. This study demonstrates that the increase of negative surface charge is not a sufficient factor determining successful assembly. Additional steric interactions provided by longer ligands are crucial for the assembly of BMV SPION VLPs and may enhance the colloidal stability.

  1. Relative binding affinity of carboxylate-, phosphonate-, and bisphosphonate-functionalized gold nanoparticles targeted to damaged bone tissue

    Energy Technology Data Exchange (ETDEWEB)

    Ross, Ryan D. [Rush University Medical Center, Department of Anatomy and Cell Biology (United States); Cole, Lisa E.; Roeder, Ryan K., E-mail: rroeder@nd.edu [University of Notre Dame, Department of Aerospace and Mechanical Engineering Bioengineering Graduate Program (United States)

    2012-10-15

    Functionalized Au NPs have received considerable recent interest for targeting and labeling cells and tissues. Damaged bone tissue can be targeted by functionalizing Au NPs with molecules exhibiting affinity for calcium. Therefore, the relative binding affinity of Au NPs surface functionalized with either carboxylate (l-glutamic acid), phosphonate (2-aminoethylphosphonic acid), or bisphosphonate (alendronate) was investigated for targeted labeling of damaged bone tissue in vitro. Targeted labeling of damaged bone tissue was qualitatively verified by visual observation and backscattered electron microscopy, and quantitatively measured by the surface density of Au NPs using field-emission scanning electron microscopy. The surface density of functionalized Au NPs was significantly greater within damaged tissue compared to undamaged tissue for each functional group. Bisphosphonate-functionalized Au NPs exhibited a greater surface density labeling damaged tissue compared to glutamic acid- and phosphonic acid-functionalized Au NPs, which was consistent with the results of previous work comparing the binding affinity of the same functionalized Au NPs to synthetic hydroxyapatite crystals. Targeted labeling was enabled not only by the functional groups but also by the colloidal stability in solution. Functionalized Au NPs were stabilized by the presence of the functional groups, and were shown to remain well dispersed in ionic (phosphate buffered saline) and serum (fetal bovine serum) solutions for up to 1 week. Therefore, the results of this study suggest that bisphosphonate-functionalized Au NPs have potential for targeted delivery to damaged bone tissue in vitro and provide motivation for in vivo investigation.

  2. TargetMiner: microRNA target prediction with systematic identification of tissue-specific negative examples.

    Science.gov (United States)

    Bandyopadhyay, Sanghamitra; Mitra, Ramkrishna

    2009-10-15

    Prediction of microRNA (miRNA) target mRNAs using machine learning approaches is an important area of research. However, most of the methods suffer from either high false positive or false negative rates. One reason for this is the marked deficiency of negative examples or miRNA non-target pairs. Systematic identification of non-target mRNAs is still not addressed properly, and therefore, current machine learning approaches are compelled to rely on artificially generated negative examples for training. In this article, we have identified approximately 300 tissue-specific negative examples using a novel approach that involves expression profiling of both miRNAs and mRNAs, miRNA-mRNA structural interactions and seed-site conservation. The newly generated negative examples are validated with pSILAC dataset, which elucidate the fact that the identified non-targets are indeed non-targets.These high-throughput tissue-specific negative examples and a set of experimentally verified positive examples are then used to build a system called TargetMiner, a support vector machine (SVM)-based classifier. In addition to assessing the prediction accuracy on cross-validation experiments, TargetMiner has been validated with a completely independent experimental test dataset. Our method outperforms 10 existing target prediction algorithms and provides a good balance between sensitivity and specificity that is not reflected in the existing methods. We achieve a significantly higher sensitivity and specificity of 69% and 67.8% based on a pool of 90 feature set and 76.5% and 66.1% using a set of 30 selected feature set on the completely independent test dataset. In order to establish the effectiveness of the systematically generated negative examples, the SVM is trained using a different set of negative data generated using the method in Yousef et al. A significantly higher false positive rate (70.6%) is observed when tested on the independent set, while all other factors are kept the

  3. A universal molecular translator for non-nucleic acid targets that enables dynamic DNA assemblies and logic operations.

    Science.gov (United States)

    Tang, Wei; Hu, Shichao; Wang, Huaming; Zhao, Yan; Li, Na; Liu, Feng

    2014-11-28

    A universal molecular translator based on the target-triggered DNA strand displacement was developed, which was able to convert various kinds of non-nucleic acid targets into a unique output DNA. This translation strategy was successfully applied in directing dynamic DNA assemblies and in realizing three-input logic gate operations.

  4. Intestinal mucosa is a target tissue for pancreatic polypeptide

    International Nuclear Information System (INIS)

    Gilbert, W.R.; Kramer, J.L.; Frank, B.H.; Gingerich, R.L.

    1986-01-01

    Studies were carried out to identify mammalian tissues capable of specifically binding mammalian pancreatic polypeptide (PP). Bovine PP (bPP) radiolabeled with 125 I was purified by HPLC to yield [ 125 I]iodo-(Tyr-27) bPP. The label was injected into three pairs of fasted littermate dogs and allowed to circulate for 5 min. One of the dogs was a control which received an excess of unlabeled porcine PP to provide competition for receptor binding. Unbound bPP was removed by perfusion with Krebs-Ringer bicarbonate and the tissue fixed in situ with Karnovsky's fixative. Tissue samples from various organs were removed, weighed, and counted. The entire gastrointestinal tract demonstrated high levels of 125 I after injection of the labeled peptide. The duodenum, jejunum, ileum, and colon were the only tissues to exhibit specific binding of bPP. These tissues (mucosal and muscle layers) from experimental animals exhibited 31-76% higher binding than the corresponding tissues from the control animals. Sections of the gastrointestinal tract were scraped to separate the mucosal layer from the underlying muscle layer. The mucosal layer of the duodenum, jejunum, and ileum exhibited 145-162% increases in binding compared to the control animals. The muscle layer of these tissues demonstrated no significant increase. These findings demonstrate that mucosal layer of the small intestine is a target tissue for mammalian PP

  5. Development of the Triple Theta assembly station with machine vision feedback

    International Nuclear Information System (INIS)

    Schmidt, Derek William

    2008-01-01

    Increased requirements for tighter tolerances on assembled target components in complex three-dimensional geometries with only days to assemble complete campaigns require the implementation of a computer-controlled high-precision assembly station. Over the last year, an 11-axis computer-controlled assembly station has been designed and built with custom software to handle the multiple coordinate systems and automatically calculate all relational positions. Preliminary development efforts have also been done to explore the benefit of a machine vision feedback module with a dual-camera viewing system to automate certain basic features like crosshair calibration, component leveling, and component centering.

  6. Functionalized Raspberry-Like Microparticles obtained by Assembly of Nanoparticles during Electrospraying

    International Nuclear Information System (INIS)

    Cho, Eun Chul; Jeong, Unyong; Hwang, Yoon Kyun

    2014-01-01

    The present study suggests a novel method to produce raspberry-like microparticles containing diverse functional materials inside. The raspberry-like microparticles were produced from a random assembly of uniformly-sized poly(methyl methacrylate) (PMMA) nanoparticles via electrospraying. The solution containing the PMMA nanoparticles were supplied through the inner nozzle and compressed air was emitted through the outer nozzle. The air supply helped fast evaporation of acetone, so it enabled copious amount of microparticles as dry powder. The microparticles were highly porous both on the surface and interiors, hence various materials with a function of UV-blocking (TiO 2 nanoparticles and methoxyphenyl triazine) or anti-aging (ethyl(4-(2,3-dihydro-1H-indene-5-carboxyamido) benzoate)) were loaded in large amount (17 wt % versus PMMA). The surface and interior structures of the microparticles were dependent on the characteristics of functional materials. The results clearly suggest that the process to prepare the raspberry-like microparticles can be an excellent approach to generate functional microstructures

  7. Self-assembly of versatile tubular-like In2O3 nanostructures

    International Nuclear Information System (INIS)

    Zhong Miao; Zheng Maojun; Ma Li; Li Yanbo

    2007-01-01

    Versatile indium oxide tubular nanostructures (well-aligned nanotube arrays, flower-like tubular structures, and square nanotubes) were fabricated by a facile and reliable chemical vapor deposition (CVD) technique, taking advantage of the self-assembly property and substrate-induced epitaxial growth mechanism. The technique has a few advantages, such as low growth temperature, nonexistence of catalyst, template-free synthesis, direct bonding to the semiconductor substrates, etc. This strategy might extend the approach of synthesizing desirable nanostructures of other important low-melting metal oxides for potential applications

  8. Layer-by-layer assembled multilayers and polymeric nanoparticles for drug delivery in tissue engineering applications

    Science.gov (United States)

    Mehrotra, Sumit

    Tissues and organs in vivo are structured in three dimensional (3-D) ordered assemblies to maintain their metabolic functions. In the case of an injury, certain tissues lack the regenerative abilities without an external supportive environment. In order to regenerate the natural in vivo environment post-injury, there is a need to design three-dimensional (3-D) tissue engineered constructs of appropriate dimensions along with strategies that can deliver growth factors or drugs at a controlled rate from such constructs. This thesis focuses on the applications of hydrogen bonded (H-bonded) nanoscale layer-by-layer (LbL) assembled multilayers for time controlled drug delivery, fabrication of polymeric nanoparticles as drug delivery carriers, and engineering 3-D cellular constructs. Axonal regeneration in the central nervous system after spinal cord injury is often disorganized and random. To support linear axonal growth into spinal cord lesion sites, certain growth factors, such as brain-derived neurotrophic factor (BDNF), needs to be delivered at a controlled rate from an array of uniaxial channels patterned in a scaffold. In this study, we demonstrate for the first time that H-bonded LbL assembled degradable thin films prepared over agarose hydrogel, whereby the protein was loaded separately from the agarose fabrication, provided sustained release of protein under physiological conditions for more than four weeks. Further, patterned agarose scaffolds implanted at the site of a spinal cord injury forms a reactive cell layer of leptomeningeal fibroblasts in and around the scaffold. This limits the ability of axons to reinnervate the spinal cord. To address this challenge, we demonstrate the time controlled release of an anti-mitotic agent from agarose hydrdgel to control the growth of the reactive cell layer of fibroblasts. Challenges in tissue engineering can also be addressed using gene therapy approaches. Certain growth factors in the body are known to inhibit

  9. Synthesis and characterization of designed BMHP1-derived self-assembling peptides for tissue engineering applications.

    Science.gov (United States)

    Silva, Diego; Natalello, Antonino; Sanii, Babak; Vasita, Rajesh; Saracino, Gloria; Zuckermann, Ronald N; Doglia, Silvia Maria; Gelain, Fabrizio

    2013-01-21

    The importance of self-assembling peptides (SAPs) in regenerative medicine is becoming increasingly recognized. The propensity of SAPs to form nanostructured fibers is governed by multiple forces including hydrogen bonds, hydrophobic interactions and π-π aromatic interactions among side chains of the amino acids. Single residue modifications in SAP sequences can significantly affect these forces. BMHP1-derived SAPs is a class of biotinylated oligopeptides, which self-assemble in β-structured fibers to form a self-healing hydrogel. In the current study, selected modifications in previously described BMHP1-derived SAPs were designed in order to investigate the influence of modified residues on self-assembly kinetics and scaffold formation properties. The Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis demonstrated the secondary structure (β-sheet) formation in all modified SAP sequences, whereas atomic force microscopy (AFM) analysis further confirmed the presence of nanofibers. Furthermore, the fiber shape and dimension analysis by AFM showed flattened and twisted fiber morphology ranging from ∼8 nm to ∼70 nm. The mechanical properties of the pre-assembled and post assembled solution were investigated by rheometry. The shear-thinning behavior and rapid re-healing properties of the pre-assembled solutions make them a preferable choice for injectable scaffolds. The wide range of stiffnesses (G')--from ∼1000 to ∼27,000 Pa--exhibited by the post-assembled scaffolds demonstrated their potential for a variety of tissue engineering applications. The extra cellular matrix (ECM) mimicking (physically and chemically) properties of SAP scaffolds enhanced cell adhesion and proliferation. The capability of the scaffold to facilitate murine neural stem cell (mNSC) proliferation was evaluated in vitro: the increased mNSCs adhesion and proliferation demonstrated the potential of newly synthesized SAPs for regenerative medicine

  10. Characterization of cells from pannus-like tissue over articular cartilage of advanced osteoarthritis.

    Science.gov (United States)

    Yuan, G-H; Tanaka, M; Masuko-Hongo, K; Shibakawa, A; Kato, T; Nishioka, K; Nakamura, H

    2004-01-01

    To identify the characteristics of cells isolated from pannus-like soft tissue on osteoarthritic cartilage (OA pannus cells), and to evaluate the role of this tissue in osteoarthritis (OA). OA pannus cells were isolated from pannus-like tissues in five joints obtained during arthroplasty. The phenotypic features of the isolated cells were characterized by safranin-O staining and immunohistochemical studies. Expression of MMP-1, MMP-3 and MMP-13 was also assessed using reverse transcriptase-polymerase chain reactions (RT-PCR), enzyme-linked immunosorbent assay (ELISA) and immunocytochemistry. Foci and plaque formation of pannus-like tissue over cartilage surface were found in 15 of 21 (71.4%) OA joints macroscopically, and among them, only five samples had enough tissue to be isolated. OA pannus cells were positive for type I collagen and vimentin, besides they also expressed type II collagen and aggrecan mRNA. Spontaneous expression of MMP-1, MMP-3 and MMP-13 was detected in OA pannus cells. Similar or higher levels of MMPs were detected in the supernatant of cultured OA pannus cells compared to OA chondrocytes, and among these MMP-3 levels were relatively higher in OA pannus cells. Immunohistochemically, MMP-3 positive cells located preferentially in pannus-like tissue on the border of original hyaline cartilage. Our results showed that OA pannus cells shared the property of mesenchymal cells and chondrocytes; however, their origin seemed different from chondrocytes or synoviocytes. The spontaneous expression of MMPs suggests that they are involved in the articular degradation in OA.

  11. Concepts for fabrication of inertial fusion energy targets

    Energy Technology Data Exchange (ETDEWEB)

    Nobile, A. (Arthur), Jr.; Hoffer, J. K. (James K.); Gobby, P. L. (Peter L.); Steckle, W. P. (Warren P.), Jr.; Goodin, D. T. (Daniel T.); Besenbruch, G. E. (Gottfried E.); Schultz, K. R. (Kenneth R.)

    2001-01-01

    Future inertial fusion energy (IFE) power plants will have a Target Fabrication Facility (TFF) that must produce approximately 500,000 targets per day. To achieve a relatively low cost of electricity, the cost to produce these targets will need to be less than approximately $0.25 per target. In this paper the status on the development of concepts for a TFF to produce targets for a heavy ion fusion (HIF) reactor, such as HYLIFE II, and a laser direct drive fusion reactor such as Sombrero, is discussed. The baseline target that is produced in the HIF TFF is similar to the close-coupled indirect drive target designed by Callahan-Miller and Tabak at Lawrence Livermore Laboratory. This target consists of a cryogenic hohlraum that is made of a metal case and a variety of metal foams and metal-doped organic foams. The target contains a DT-filled CH capsule. The baseline direct drive target is the design developed by Bodner and coworkers at Naval Research Laboratory. HIF targets can be filled with DT before or after assembly of the capsule into the hohlraum. Assembly of targets before filling allows assembly operations to be done at room temperature, but tritium inventories are much larger due to the large volume that the hohlraum occupies in the fill system. Assembly of targets cold after filling allows substantial reduction in tritium inventory, but this requires assembly of targets at cryogenic temperature. A model being developed to evaluate the tritium inventories associated with each of the assembly and fill options indicates that filling targets before assembling the capsule into the hohlraum, filling at temperatures as high as possible, and reducing dead-volumes in the fill system as much as possible offers the potential to reduce tritium inventories to acceptable levels. Use of enhanced DT ice layering techniques, such as infrared layering can reduce tritium inventories significantly by reducing the layering time and therefore the number of capsules being layered

  12. Self-assembly of Fe3O4 nanocrystal-clusters into cauliflower-like architectures: Synthesis and characterization

    International Nuclear Information System (INIS)

    Zhu Luping; Liao Guihong; Bing Naici; Wang Linlin; Xie Hongyong

    2011-01-01

    Large-scale cauliflower-like Fe 3 O 4 architectures consist of well-assembled magnetite nanocrystal clusters have been synthesized by a simple solvothermal process. The as-synthesized Fe 3 O 4 samples were characterized by XRD, XPS, FT-IR, SEM, TEM, etc. The results show that the samples exhibit cauliflower-like hierarchical microstructures. The influences of synthesis parameters on the morphology of the samples were experimentally investigated. Magnetic properties of the Fe 3 O 4 cauliflower-like hierarchical microstructures have been detected by VSM at room temperature, showing a relatively low saturation magnetization of 65 emu/g and an enhanced coercive force of 247 Oe. - Graphical Abstract: Cauliflower-like Fe 3 O 4 architectures consist of well-assembled magnetite nanocrystal clusters have been synthesized by a simple solvothermal process, using FeCl 3 .6H 2 O and EDA as the starting materials. Highlights: → Cauliflower-like Fe 3 O 4 architectures were successfully prepared by a simple solvothermal route. → The cauliflower-like Fe 3 O 4 architectures have a size in the range of 200-300 nm. → They show a low saturation magnetization of 65 emu/g and an enhanced coercive force of 247 Oe. → These Fe 3 O 4 architectures may have potential applications in catalysis and biological fields.

  13. Self-assembling peptide nanofiber hydrogels in tissue engineering and regenerative medicine: Progress, design guidelines, and applications.

    Science.gov (United States)

    Koutsopoulos, Sotirios

    2016-04-01

    Until the mid-1980s, mainly biologists were conducting peptide research. This changed with discoveries that opened new paths of research involving the use of peptides in bioengineering, biotechnology, biomedicine, nanotechnology, and bioelectronics. Peptide engineering and rational design of novel peptide sequences with unique and tailor-made properties further expanded the field. The discovery of short self-assembling peptides, which upon association form well-defined supramolecular architectures, created new and exciting areas of research. Depending on the amino acid sequence, the pH, and the type of the electrolyte in the medium, peptide self-assembly leads to the formation of nanofibers, which are further organized to form a hydrogel. In this review, the application of ionic complementary peptides which self-assemble to form nanofiber hydrogels for tissue engineering and regenerative medicine will be discussed through a selective presentation of the most important work performed during the last 25 years. © 2016 Wiley Periodicals, Inc.

  14. Ligand-targeted delivery of small interfering RNAs to malignant cells and tissues.

    Science.gov (United States)

    Thomas, Mini; Kularatne, Sumith A; Qi, Longwu; Kleindl, Paul; Leamon, Christopher P; Hansen, Michael J; Low, Philip S

    2009-09-01

    Potential clinical applications of small interfering RNA (siRNA) are hampered primarily by delivery issues. We have successfully addressed the delivery problems associated with off-site targeting of highly toxic chemotherapeutic agents by attaching the drugs to tumor-specific ligands that will carry the attached cargo into the desired cancer cell. Indeed, several such tumor-targeted drugs are currently undergoing human clinical trials. We now show that efficient targeting of siRNA to malignant cells and tissues can be achieved by covalent conjugation of small-molecular-weight, high-affinity ligands, such as folic acid and DUPA (2-[3-(1, 3-dicarboxy propyl)-ureido] pentanedioic acid), to siRNA. The former ligand binds a folate receptor that is overexpressed on a variety of cancers, whereas the latter ligand binds to prostate-specific membrane antigen that is overexpressed specifically on prostate cancers and the neovasculature of all solid tumors. Using these ligands, we show remarkable receptor-mediated targeting of siRNA to cancer tissues in vitro and in vivo.

  15. Identification and target prediction of miRNAs specifically expressed in rat neural tissue

    Directory of Open Access Journals (Sweden)

    Tu Kang

    2009-05-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are a large group of RNAs that play important roles in regulating gene expression and protein translation. Several studies have indicated that some miRNAs are specifically expressed in human, mouse and zebrafish tissues. For example, miR-1 and miR-133 are specifically expressed in muscles. Tissue-specific miRNAs may have particular functions. Although previous studies have reported the presence of human, mouse and zebrafish tissue-specific miRNAs, there have been no detailed reports of rat tissue-specific miRNAs. In this study, Home-made rat miRNA microarrays which established in our previous study were used to investigate rat neural tissue-specific miRNAs, and mapped their target genes in rat tissues. This study will provide information for the functional analysis of these miRNAs. Results In order to obtain as complete a picture of specific miRNA expression in rat neural tissues as possible, customized miRNA microarrays with 152 selected miRNAs from miRBase were used to detect miRNA expression in 14 rat tissues. After a general clustering analysis, 14 rat tissues could be clearly classified into neural and non-neural tissues based on the obtained expression profiles with p values Conclusion Our work provides a global view of rat neural tissue-specific miRNA profiles and a target map of miRNAs, which is expected to contribute to future investigations of miRNA regulatory mechanisms in neural systems.

  16. The Properties of the Massive Star-forming Galaxies with an Outside-in Assembly Mode

    Science.gov (United States)

    Wang, Enci; Kong, Xu; Wang, Huiyuan; Wang, Lixin; Lin, Lin; Gao, Yulong; Liu, Qing

    2017-08-01

    Previous findings show that massive ({M}* > {10}10 {M}⊙ ) star-forming (SF) galaxies usually have an “inside-out” stellar mass assembly mode. In this paper, we have for the first time selected a sample of 77 massive SF galaxies with an “outside-in” assembly mode (called the “targeted sample”) from the Mapping Nearby Galaxies at the Apache Point Observatory (MaNGA) survey. For comparison, two control samples are constructed from the MaNGA sample matched in stellar mass: a sample of 154 normal SF galaxies and a sample of 62 quiescent galaxies. In contrast to normal SF galaxies, the targeted galaxies appear to be smoother and more bulge-dominated and have a smaller size and higher concentration, star formation rate, and gas-phase metallicity as a whole. However, they have a larger size and lower concentration than quiescent galaxies. Unlike the normal SF sample, the targeted sample exhibits a slightly positive gradient of the 4000 Å break and a pronounced negative gradient of Hα equivalent width. Furthermore, the median surface mass density profile is between those of the normal SF and quiescent samples, indicating that the gas accretion of quiescent galaxies is not likely to be the main approach for the outside-in assembly mode. Our results suggest that the targeted galaxies are likely in the transitional phase from normal SF galaxies to quiescent galaxies, with rapid ongoing central stellar mass assembly (or bulge growth). We discuss several possible formation mechanisms for the outside-in mass assembly mode.

  17. Differentiating Immune Cell Targets in Gut-Associated Lymphoid Tissue for HIV Cure.

    Science.gov (United States)

    Khan, Shahzada; Telwatte, Sushama; Trapecar, Martin; Yukl, Steven; Sanjabi, Shomyseh

    2017-11-01

    The single greatest challenge to an HIV cure is the persistence of latently infected cells containing inducible, replication-competent proviral genomes, which constitute only a small fraction of total or infected cells in the body. Although resting CD4 + T cells in the blood are a well-known source of viral rebound, more than 90% of the body's lymphocytes reside elsewhere. Many are in gut tissue, where HIV DNA levels per million CD4 + T cells are considerably higher than in the blood. Despite the significant contribution of gut tissue to viral replication and persistence, little is known about the cell types that support persistence of HIV in the gut; importantly, T cells in the gut have phenotypic, functional, and survival properties that are distinct from T cells in other tissues. The mechanisms by which latency is established and maintained will likely depend on the location and cytokine milieu surrounding the latently infected cells in each compartment. Therefore, successful HIV cure strategies require identification and characterization of the exact cell types that support viral persistence, particularly in the gut. In this review, we describe the seeding of the latent HIV reservoir in the gut mucosa; highlight the evidence for compartmentalization and depletion of T cells; summarize the immunologic consequences of HIV infection within the gut milieu; propose how the damaged gut environment may promote the latent HIV reservoir; and explore several immune cell targets in the gut and their place on the path toward HIV cure.

  18. Controlled doping by self-assembled dendrimer-like macromolecules

    Science.gov (United States)

    Wu, Haigang; Guan, Bin; Sun, Yingri; Zhu, Yiping; Dan, Yaping

    2017-02-01

    Doping via self-assembled macromolecules might offer a solution for developing single atom electronics by precisely placing individual dopants at arbitrary location to meet the requirement for circuit design. Here we synthesize dendrimer-like polyglycerol macromolecules with each carrying one phosphorus atom in the core. The macromolecules are immobilized by the coupling reagent onto silicon surfaces that are pre-modified with a monolayer of undecylenic acid. Nuclear magnetic resonance (NMR) and X-ray photoelectron spectroscopy (XPS) are employed to characterize the synthesized macromolecules and the modified silicon surfaces, respectively. After rapid thermal annealing, the phosphorus atoms carried by the macromolecules diffuse into the silicon substrate, forming dopants at a concentration of 1017 cm-3. Low-temperature Hall effect measurements reveal that the ionization process is rather complicated. Unlike the widely reported simple ionization of phosphorus dopants, nitrogen and carbon are also involved in the electronic activities in the monolayer doped silicon.

  19. A hyaluronan-based scaffold for the in vitro construction of dental pulp-like tissue.

    Science.gov (United States)

    Ferroni, Letizia; Gardin, Chiara; Sivolella, Stefano; Brunello, Giulia; Berengo, Mario; Piattelli, Adriano; Bressan, Eriberto; Zavan, Barbara

    2015-03-02

    Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D) hyaluronan scaffold and human dental pulp stem cells (DPSCs) to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF) staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  20. A Hyaluronan-Based Scaffold for the in Vitro Construction of Dental Pulp-Like Tissue

    Directory of Open Access Journals (Sweden)

    Letizia Ferroni

    2015-03-01

    Full Text Available Dental pulp tissue supports the vitality of the tooth, but it is particularly vulnerable to external insults, such as mechanical trauma, chemical irritation or microbial invasion, which can lead to tissue necrosis. In the present work, we present an endodontic regeneration method based on the use of a tridimensional (3D hyaluronan scaffold and human dental pulp stem cells (DPSCs to produce a functional dental pulp-like tissue in vitro. An enriched population of DPSCs was seeded onto hyaluronan-based non-woven meshes in the presence of differentiation factors to induce the commitment of stem cells to neuronal, glial, endothelial and osteogenic phenotypes. In vitro experiments, among which were gene expression profiling and immunofluorescence (IF staining, proved the commitment of DPSCs to the main components of dental pulp tissue. In particular, the hyaluronan-DPSCs construct showed a dental pulp-like morphology consisting of several specialized cells growing inside the hyaluronan fibers. Furthermore, these constructs were implanted into rat calvarial critical-size defects. Histological analyses and gene expression profiling performed on hyaluronan-DPSCs grafts showed the regeneration of osteodentin-like tissue. Altogether, these data suggest the regenerative potential of the hyaluronan-DPSC engineered tissue.

  1. Contact assembly of cell-laden hollow microtubes through automated micromanipulator tip locating

    International Nuclear Information System (INIS)

    Wang, Huaping; Shi, Qing; Guo, Yanan; Li, Yanan; Sun, Tao; Huang, Qiang; Fukuda, Toshio

    2017-01-01

    This paper presents an automated contact assembly method to fabricate a cell-laden microtube based on accurate locating of the micromanipulator tip. Essential for delivering nutrients in thick engineered tissues, a vessel-mimetic microtube can be precisely assembled through microrobotic contact biomanipulation. The biomanipulation is a technique to spatially order and immobilize cellular targets with high precision. However, due to image occlusion during contact, it is challenging to locate the micromanipulator tip for fully automated assembly. To achieve pixel-wise tracking and locating of the tip in contact, a particle filter algorithm integrated with a determined level set model is employed here. The model ensures precise convergence of the micromanipulator’s contour during occlusion. With the converged active contour, the algorithm is able to pixel-wisely separate the micromanipulator from the low-contrast background and precisely locate the tip with error around 1 pixel (2 µ m at 4  ×  magnification). As a result, the cell-laden microtube is automatically assembled at six layers/min, which is effective enough to fabricate vessel-mimetic constructs for vascularization in tissue engineering. (paper)

  2. Chimeric L2-Based Virus-Like Particle (VLP Vaccines Targeting Cutaneous Human Papillomaviruses (HPV.

    Directory of Open Access Journals (Sweden)

    Bettina Huber

    Full Text Available Common cutaneous human papillomavirus (HPV types induce skin warts, whereas species beta HPV are implicated, together with UV-radiation, in the development of non-melanoma skin cancer (NMSC in immunosuppressed patients. Licensed HPV vaccines contain virus-like particles (VLP self-assembled from L1 major capsid proteins that provide type-restricted protection against mucosal HPV infections causing cervical and other ano-genital and oro-pharyngeal carcinomas and warts (condylomas, but do not target heterologous HPV. Experimental papillomavirus vaccines have been designed based on L2 minor capsid proteins that contain type-common neutralization epitopes, to broaden protection to heterologous mucosal and cutaneous HPV types. Repetitive display of the HPV16 L2 cross-neutralization epitope RG1 (amino acids (aa 17-36 on the surface of HPV16 L1 VLP has greatly enhanced immunogenicity of the L2 peptide. To more directly target cutaneous HPV, L1 fusion proteins were designed that incorporate the RG1 homolog of beta HPV17, the beta HPV5 L2 peptide aa53-72, or the common cutaneous HPV4 RG1 homolog, inserted into DE surface loops of HPV1, 5, 16 or 18 L1 VLP scaffolds. Baculovirus expressed chimeric proteins self-assembled into VLP and VLP-raised NZW rabbit immune sera were evaluated by ELISA and L1- and L2-based pseudovirion (PsV neutralizing assays, including 12 novel beta PsV types. Chimeric VLP displaying the HPV17 RG1 epitope, but not the HPV5L2 aa53-72 epitope, induced cross-neutralizing humoral immune responses to beta HPV. In vivo cross-protection was evaluated by passive serum transfer in a murine PsV challenge model. Immune sera to HPV16L1-17RG1 VLP (cross- protected against beta HPV5/20/24/38/96/16 (but not type 76, while antisera to HPV5L1-17RG1 VLP cross-protected against HPV20/24/96 only, and sera to HPV1L1-4RG1 VLP cross-protected against HPV4 challenge. In conclusion, RG1-based VLP are promising next generation vaccine candidates to target

  3. Thermoresponsive self-assembly of short elastin-like polypentapeptides and their poly(ethylene glycol) derivatives

    Czech Academy of Sciences Publication Activity Database

    Pechar, Michal; Brus, Jiří; Kostka, Libor; Koňák, Čestmír; Urbanová, Martina; Šlouf, Miroslav

    2007-01-01

    Roč. 7, č. 1 (2007), s. 56-69 ISSN 1616-5187 R&D Projects: GA ČR GA204/05/2255; GA AV ČR IAA100500501 Institutional research plan: CEZ:AV0Z40500505 Keywords : elastin -like peptides * self-assembly * poly(ethylene glycol) Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.831, year: 2007

  4. Hierarchical Design of Tissue Regenerative Constructs.

    Science.gov (United States)

    Rose, Jonas C; De Laporte, Laura

    2018-03-01

    The worldwide shortage of organs fosters significant advancements in regenerative therapies. Tissue engineering and regeneration aim to supply or repair organs or tissues by combining material scaffolds, biochemical signals, and cells. The greatest challenge entails the creation of a suitable implantable or injectable 3D macroenvironment and microenvironment to allow for ex vivo or in vivo cell-induced tissue formation. This review gives an overview of the essential components of tissue regenerating scaffolds, ranging from the molecular to the macroscopic scale in a hierarchical manner. Further, this review elaborates about recent pivotal technologies, such as photopatterning, electrospinning, 3D bioprinting, or the assembly of micrometer-scale building blocks, which enable the incorporation of local heterogeneities, similar to most native extracellular matrices. These methods are applied to mimic a vast number of different tissues, including cartilage, bone, nerves, muscle, heart, and blood vessels. Despite the tremendous progress that has been made in the last decade, it remains a hurdle to build biomaterial constructs in vitro or in vivo with a native-like structure and architecture, including spatiotemporal control of biofunctional domains and mechanical properties. New chemistries and assembly methods in water will be crucial to develop therapies that are clinically translatable and can evolve into organized and functional tissues. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Analysis of the thermomechanical behavior of the IFMIF bayonet target assembly under design loading scenarios

    Energy Technology Data Exchange (ETDEWEB)

    Bernardi, D., E-mail: davide.bernardi@enea.it [ENEA Brasimone, Camugnano, BO (Italy); Arena, P.; Bongiovì, G.; Di Maio, P.A. [Dipartimento di Energia, Ingegneria dell’Informazione e Modelli Matematici, Università di Palermo, Viale delle Scienze, Palermo (Italy); Frisoni, M. [ENEA Bologna, Via Martiri di Monte Sole 4, Bologna (Italy); Miccichè, G.; Serra, M. [ENEA Brasimone, Camugnano, BO (Italy)

    2015-10-15

    In the framework of the IFMIF Engineering Validation and Engineering Design Activities (IFMIF/EVEDA) phase, ENEA is responsible for the design of the European concept of the IFMIF lithium target system which foresees the possibility to periodically replace only the most irradiated and thus critical component (i.e., the backplate) while continuing to operate the rest of the target for a longer period (the so-called bayonet backplate concept). In this work, the results of the steady state thermomechanical analysis of the IFMIF bayonet target assembly under two different design loading scenarios (a “hot” scenario and a “cold” scenario) are briefly reported highlighting the relevant indications obtained with respect to the fulfillment of the design requirements. In particular, the analyses have shown that in the hot scenario the temperatures reached in the target assembly are within the material acceptable limits while in the cold scenario transition below the ductile to brittle transition temperature (DBTT) cannot be excluded. Moreover, results indicate that the contact between backplate and high flux test module is avoided and that the overall structural integrity of the system is assured in both scenarios. However, stress linearization analysis reveals that ITER Structural Design Criteria for In-vessel Components (SDC-IC) design rules are not always met along the selected paths at backplate middle plane section in the hot scenario, thus suggesting the need of a revision of the backplate design or a change of the operating conditions.

  6. Recombinant epidermal growth factor-like domain-1 from coagulation factor VII functionalized iron oxide nanoparticles for targeted glioma magnetic resonance imaging.

    Science.gov (United States)

    Liu, Heng; Chen, Xiao; Xue, Wei; Chu, Chengchao; Liu, Yu; Tong, Haipeng; Du, Xuesong; Xie, Tian; Liu, Gang; Zhang, Weiguo

    The highly infiltrative and invasive nature of glioma cells often leads to blurred tumor margins, resulting in incomplete tumor resection and tumor recurrence. Accurate detection and precise delineation of glioma help in preoperative delineation, surgical planning and survival prediction. In this study, recombinant epidermal growth factor-like domain-1, derived from human coagulation factor VII, was conjugated to iron oxide nanoparticles (IONPs) for targeted glioma magnetic resonance (MR) imaging. The synthesized EGF1-EGFP-IONPs exhibited excellent targeting ability toward tissue factor (TF)-positive U87MG cells and human umbilical vein endothelial cells in vitro, and demonstrated persistent and efficient MR contrast enhancement up to 12 h for preclinical glioma models with high targeting specificity in vivo. They hold great potential for clinical translation and developing targeted theranostics against brain glioma.

  7. Engineering on the straight and narrow: the mechanics of nanofibrous assemblies for fiber-reinforced tissue regeneration.

    Science.gov (United States)

    Mauck, Robert L; Baker, Brendon M; Nerurkar, Nandan L; Burdick, Jason A; Li, Wan-Ju; Tuan, Rocky S; Elliott, Dawn M

    2009-06-01

    Tissue engineering of fibrous tissues of the musculoskeletal system represents a considerable challenge because of the complex architecture and mechanical properties of the component structures. Natural healing processes in these dense tissues are limited as a result of the mechanically challenging environment of the damaged tissue and the hypocellularity and avascular nature of the extracellular matrix. When healing does occur, the ordered structure of the native tissue is replaced with a disorganized fibrous scar with inferior mechanical properties, engendering sites that are prone to re-injury. To address the engineering of such tissues, we and others have adopted a structurally motivated approach based on organized nanofibrous assemblies. These scaffolds are composed of ultrafine polymeric fibers that can be fabricated in such a way to recreate the structural anisotropy typical of fiber-reinforced tissues. This straight-and-narrow topography not only provides tailored mechanical properties, but also serves as a 3D biomimetic micropattern for directed tissue formation. This review describes the underlying technology of nanofiber production and focuses specifically on the mechanical evaluation and theoretical modeling of these structures as it relates to native tissue structure and function. Applying the same mechanical framework for understanding native and engineered fiber-reinforced tissues provides a functional method for evaluating the utility and maturation of these unique engineered constructs. We further describe several case examples where these principles have been put to test, and discuss the remaining challenges and opportunities in forwarding this technology toward clinical implementation.

  8. Engineering on the Straight and Narrow: The Mechanics of Nanofibrous Assemblies for Fiber-Reinforced Tissue Regeneration

    Science.gov (United States)

    Baker, Brendon M.; Nerurkar, Nandan L.; Burdick, Jason A.; Li, Wan-Ju; Tuan, Rocky S.; Elliott, Dawn M.

    2009-01-01

    Tissue engineering of fibrous tissues of the musculoskeletal system represents a considerable challenge because of the complex architecture and mechanical properties of the component structures. Natural healing processes in these dense tissues are limited as a result of the mechanically challenging environment of the damaged tissue and the hypocellularity and avascular nature of the extracellular matrix. When healing does occur, the ordered structure of the native tissue is replaced with a disorganized fibrous scar with inferior mechanical properties, engendering sites that are prone to re-injury. To address the engineering of such tissues, we and others have adopted a structurally motivated approach based on organized nanofibrous assemblies. These scaffolds are composed of ultrafine polymeric fibers that can be fabricated in such a way to recreate the structural anisotropy typical of fiber-reinforced tissues. This straight-and-narrow topography not only provides tailored mechanical properties, but also serves as a 3D biomimetic micropattern for directed tissue formation. This review describes the underlying technology of nanofiber production and focuses specifically on the mechanical evaluation and theoretical modeling of these structures as it relates to native tissue structure and function. Applying the same mechanical framework for understanding native and engineered fiber-reinforced tissues provides a functional method for evaluating the utility and maturation of these unique engineered constructs. We further describe several case examples where these principles have been put to test, and discuss the remaining challenges and opportunities in forwarding this technology toward clinical implementation. PMID:19207040

  9. Cooperative effects of fibronectin matrix assembly and initial cell-substrate adhesion strength in cellular self-assembly.

    Science.gov (United States)

    Brennan, James R; Hocking, Denise C

    2016-03-01

    The cell-dependent polymerization of intercellular fibronectin fibrils can stimulate cells to self-assemble into multicellular structures. The local physical cues that support fibronectin-mediated cellular self-assembly are largely unknown. Here, fibronectin matrix analogs were used as synthetic adhesive substrates to model cell-matrix fibronectin fibrils having different integrin-binding specificity, affinity, and/or density. We utilized this model to quantitatively assess the relationship between adhesive forces derived from cell-substrate interactions and the ability of fibronectin fibril assembly to induce cellular self-assembly. Results indicate that the strength of initial, rather than mature, cell-substrate attachments correlates with the ability of substrates to support fibronectin-mediated cellular self-assembly. The cellular response to soluble fibronectin was bimodal and independent of the integrin-binding specificity of the substrate; increasing soluble fibronectin levels above a critical threshold increased aggregate cohesion on permissive substrates. Once aggregates formed, continuous fibronectin polymerization was necessary to maintain cohesion. During self-assembly, soluble fibronectin decreased cell-substrate adhesion strength and induced aggregate cohesion via a Rho-dependent mechanism, suggesting that the balance of contractile forces derived from fibronectin fibrils within cell-cell versus cell-substrate adhesions controls self-assembly and aggregate cohesion. Thus, initial cell-substrate attachment strength may provide a quantitative basis with which to build predictive models of fibronectin-mediated microtissue fabrication on a variety of substrates. Cellular self-assembly is a process by which cells and extracellular matrix (ECM) proteins spontaneously organize into three-dimensional (3D) tissues in the absence of external forces. Cellular self-assembly can be initiated in vitro, and represents a potential tool for tissue engineers to

  10. Targeted nanodiamonds for identification of subcellular protein assemblies in mammalian cells

    Science.gov (United States)

    Lake, Michael P.; Bouchard, Louis-S.

    2017-01-01

    Transmission electron microscopy (TEM) can be used to successfully determine the structures of proteins. However, such studies are typically done ex situ after extraction of the protein from the cellular environment. Here we describe an application for nanodiamonds as targeted intensity contrast labels in biological TEM, using the nuclear pore complex (NPC) as a model macroassembly. We demonstrate that delivery of antibody-conjugated nanodiamonds to live mammalian cells using maltotriose-conjugated polypropylenimine dendrimers results in efficient localization of nanodiamonds to the intended cellular target. We further identify signatures of nanodiamonds under TEM that allow for unambiguous identification of individual nanodiamonds from a resin-embedded, OsO4-stained environment. This is the first demonstration of nanodiamonds as labels for nanoscale TEM-based identification of subcellular protein assemblies. These results, combined with the unique fluorescence properties and biocompatibility of nanodiamonds, represent an important step toward the use of nanodiamonds as markers for correlated optical/electron bioimaging. PMID:28636640

  11. Targeted nanodiamonds for identification of subcellular protein assemblies in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Michael P Lake

    Full Text Available Transmission electron microscopy (TEM can be used to successfully determine the structures of proteins. However, such studies are typically done ex situ after extraction of the protein from the cellular environment. Here we describe an application for nanodiamonds as targeted intensity contrast labels in biological TEM, using the nuclear pore complex (NPC as a model macroassembly. We demonstrate that delivery of antibody-conjugated nanodiamonds to live mammalian cells using maltotriose-conjugated polypropylenimine dendrimers results in efficient localization of nanodiamonds to the intended cellular target. We further identify signatures of nanodiamonds under TEM that allow for unambiguous identification of individual nanodiamonds from a resin-embedded, OsO4-stained environment. This is the first demonstration of nanodiamonds as labels for nanoscale TEM-based identification of subcellular protein assemblies. These results, combined with the unique fluorescence properties and biocompatibility of nanodiamonds, represent an important step toward the use of nanodiamonds as markers for correlated optical/electron bioimaging.

  12. Targeted nanodiamonds for identification of subcellular protein assemblies in mammalian cells.

    Science.gov (United States)

    Lake, Michael P; Bouchard, Louis-S

    2017-01-01

    Transmission electron microscopy (TEM) can be used to successfully determine the structures of proteins. However, such studies are typically done ex situ after extraction of the protein from the cellular environment. Here we describe an application for nanodiamonds as targeted intensity contrast labels in biological TEM, using the nuclear pore complex (NPC) as a model macroassembly. We demonstrate that delivery of antibody-conjugated nanodiamonds to live mammalian cells using maltotriose-conjugated polypropylenimine dendrimers results in efficient localization of nanodiamonds to the intended cellular target. We further identify signatures of nanodiamonds under TEM that allow for unambiguous identification of individual nanodiamonds from a resin-embedded, OsO4-stained environment. This is the first demonstration of nanodiamonds as labels for nanoscale TEM-based identification of subcellular protein assemblies. These results, combined with the unique fluorescence properties and biocompatibility of nanodiamonds, represent an important step toward the use of nanodiamonds as markers for correlated optical/electron bioimaging.

  13. Tile-based self-assembly of a triple-helical polysaccharide into cell wall-like mesoporous nanocapsules.

    Science.gov (United States)

    Wu, Chaoxi; Wang, Xiaoying; Wang, Jianjing; Zhang, Zhen; Wang, Zhiping; Wang, Yifei; Tang, Shunqing

    2017-07-20

    Tile-based self-assembly is a robust system in the construction of three-dimensional DNA nanostructures but it has been rarely applied to other helical biopolymers. β-Glucan is an immunoactive natural polymer which exists in a triple helical conformation. Herein, we report that β-glucan, after modification using two types of short chain acyl groups, can self-assemble into tiles with inactivated sticky ends at the interface of two solvents. These tiles consist of a single layer of helices laterally aligned, and the sticky ends can be activated when a few acyl groups at the ends are removed; these tiles can further pack into mesoporous nanocapsules, in a similar process as the sticky DNA tiles pack into complex polyhedral nano-objects. These nanocapsules were found to have targeted effects to antigen presenting cells in a RAW264.7 cell model. Our study suggests that tile-based self-assembly can be a general strategy for helical biopolymers, and on fully exploiting this strategy, various new functional nanostructures will become accessible in the future.

  14. Self-assembly growth of alloyed NiPt nanocrystals with holothuria-like shape for oxygen evolution reaction with enhanced catalytic activity

    Directory of Open Access Journals (Sweden)

    Tao Ding

    2016-01-01

    Full Text Available Self-assembly growth of alloyed NiPt nanocrystals with holothuria-like wire shape has been achieved via a facile and moderate hydrothermal process at 120 °C for 1 h from the reaction of nickel nitrate and chloroplatinic acid in alkaline solution in the presence of ethanediamine and hydrazine hydrate. The holothuria-like alloyed NiPt wires are Ni-rich in composition (Ni23.6Pt and uniform in diameter with many tiny tips outstretched from the wires surface. The holothuria-like wires are assembled from granular subunits with the assistance of capping molecular of ethanediamine and the wires display an improved oxygen evolution reaction catalytic activity.

  15. A possible connective tissue primary lymphoepithelioma-like carcinoma (LELC)

    OpenAIRE

    Aurilio, G; Ricci, V; De Vita, F; Fasano, M; Fazio, N; Orditura, M; Funicelli, L; De Luca, G; Iasevoli, D; Iovino, F; Ciardiello, F; Conzo, G; Nol?, F; Lamendola, MG

    2010-01-01

    Lymphoepithelial carcinoma is an undifferentiated nasopharyngeal carcinoma with lymphoid stroma and non-keratinizing squamous cells with distinctive clinical, epidemiological and etiological features. Conversely, lymphoepithelioma-like carcinomas (LELCs) are carcinomas that arise outside the nasopharynx but resemble a lymphoepithelioma histologically. In this case study, LELC presentation in connective tissue (left sternocleidomastoid muscle) is peculiar and unusual, but its diagnosis is supp...

  16. Hot target assembly at 14 UD Pelletron Accelerator Facility, BARC- TIFR, Mumbai

    International Nuclear Information System (INIS)

    Sharma, S.C.; Ramjilal; Ninawe, N.G.; Bhagwat, P.V.; Ahmeabadhai, P.; Kain, V.

    2005-01-01

    BARC-TIFR 14 UD Pelletron Accelerator Facility at Mumbai is operational since 1989 with progressively increased efficiency. The accelerator has been serving as major facility for heavy ion based research in India. There is an increased demand for high current proton beam, especially on heated targets for reactor physics based experiments. A proton beam setup is commissioned in the tower area of the existing facility itself, which provide proton beam of energy 2 MeV to 26 MeV with maximum 3 μA current. This setup is being used to produce radioisotopes and tracer packets. Proton beam of few MeV in μA current range is also needed to study radiation effects on metals at higher temperature, for use in reactors. For this purpose a hot target assembly has been designed and is being currently used at the Pelletron Accelerator

  17. Prediction of solvent dependent Beta-roll formation of a self-assembling silk-like protein domain

    NARCIS (Netherlands)

    Schor, M.; Martens, A.A.; Wolf, de F.A.; Cohen Stuart, M.A.; Bolhuis, P.G.

    2009-01-01

    Triblock copolymers consisting of a middle silk-like [(Gly-Ala)3-Gly-Glu]n block flanked by two hydrophilic end blocks that assume a random conformation in aqueous solution at all pH spontaneously assemble into micrometre long fibers at low pH. As elucidating the molecular structure of the stacked

  18. Prediction of solvent dependent beta-roll formation of a self-assembling silk-like protein domain

    NARCIS (Netherlands)

    Schor, M.; Martens, A.A.; de Wolf, F.A.; Cohen Stuart, M.A.; Bolhuis, P.G.

    2009-01-01

    Triblock copolymers consisting of a middle silk-like [(Gly - Ala)(3) - Gly - Glu](n) block flanked by two hydrophilic end blocks that assume a random conformation in aqueous solution at all pH spontaneously assemble into micrometre long fibers at low pH. As elucidating the molecular structure of the

  19. Curcumin targets breast cancer stem-like cells with microtentacles that persist in mammospheres and promote reattachment.

    Science.gov (United States)

    Charpentier, Monica S; Whipple, Rebecca A; Vitolo, Michele I; Boggs, Amanda E; Slovic, Jana; Thompson, Keyata N; Bhandary, Lekhana; Martin, Stuart S

    2014-02-15

    Cancer stem-like cells (CSC) and circulating tumor cells (CTC) have related properties associated with distant metastasis, but the mechanisms through which CSCs promote metastasis are unclear. In this study, we report that breast cancer cell lines with more stem-like properties display higher levels of microtentacles (McTN), a type of tubulin-based protrusion of the plasma cell membrane that forms on detached or suspended cells and aid in cell reattachment. We hypothesized that CSCs with large numbers of McTNs would more efficiently attach to distant tissues, promoting metastatic efficiency. The naturally occurring stem-like subpopulation of the human mammary epithelial (HMLE) cell line presents increased McTNs compared with its isogenic non-stem-like subpopulation. This increase was supported by elevated α-tubulin detyrosination and vimentin protein levels and organization. Increased McTNs in stem-like HMLEs promoted a faster initial reattachment of suspended cells that was inhibited by the tubulin-directed drug, colchicine, confirming a functional role for McTNs in stem cell reattachment. Moreover, live-cell confocal microscopy showed that McTNs persist in breast stem cell mammospheres as flexible, motile protrusions on the surface of the mammosphere. Although exposed to the environment, they also function as extensions between adjacent cells along cell-cell junctions. We found that treatment with the breast CSC-targeting compound curcumin rapidly extinguished McTN in breast CSC, preventing reattachment from suspension. Together, our results support a model in which breast CSCs with cytoskeletal alterations that promote McTNs can mediate attachment and metastasis but might be targeted by curcumin as an antimetastatic strategy. ©2013 AACR.

  20. Controlled self-assembly of PbS nanoparticles into macrostar-like hierarchical structures

    International Nuclear Information System (INIS)

    Li, Guowei; Li, Changsheng; Tang, Hua; Cao, Kesheng; Chen, Juan

    2011-01-01

    Graphical abstract: The aggregation and rotation of nanoparticles to adopt parallel orientations in three dimensions was indirectly illustrated by TEM and HRTEM images. Highlights: → Macrostar-like PbS hierarchical structures was successfully synthesized by a simple hydrothermal method and mesostars were assembled from the PbS nanocube building blocks with edge lengths of about 100 nm. → Ostwald-ripening-assisted oriented attachment is believed to play a key role in the growth behavior of novel 3D structures. → Optical properties indicating few defects on the surface of the PbS structure and exhibit large blue-shifts compared to bulk PbS. -- Abstract: The synthesis of macrostar-like PbS hierarchical structures by a simple hydrothermal method at 180 o C for 24 h is proven successful with the assistance of a new surfactant called tetrabutylammonium bromide (TBAB). The as-obtained product is characterized by means of X-ray powder diffraction, field emission scanning electron microscopy, energy dispersive spectrometry, high resolution transmission electron microscopy, and selected area electron diffraction. The presence of TBAB and NaF plays an important role in the formation of PbS macrostructures. Ostwald-ripening-assisted oriented attachment is believed to play a key role in the growth behavior of novel 3D structures. As such, a possible self-assembly mechanism is proposed to explain the formation of the said structures. The present study aims to introduce new insights into understanding the formation process of such unique hierarchical superstructures.

  1. Electroactive oligoaniline-containing self-assembled monolayers for tissue engineering applications.

    Science.gov (United States)

    Guo, Yi; Li, Mengyan; Mylonakis, Andreas; Han, Jingjia; MacDiarmid, Alan G; Chen, Xuesi; Lelkes, Peter I; Wei, Yen

    2007-10-01

    A novel electroactive silsesquioxane precursor, N-(4-aminophenyl)-N'-(4'-(3-triethoxysilyl-propyl-ureido) phenyl-1,4-quinonenediimine) (ATQD), was successfully synthesized from the emeraldine form of amino-capped aniline trimers via a one-step coupling reaction and subsequent purification by column chromatography. The physicochemical properties of ATQD were characterized using mass spectrometry as well as by nuclear magnetic resonance and UV-vis spectroscopy. Analysis by cyclic voltammetry confirmed that the intrinsic electroactivity of ATQD was maintained upon protonic acid doping, exhibiting two distinct reversible oxidative states, similar to polyaniline. The aromatic amine terminals of self-assembled monolayers (SAMs) of ATQD on glass substrates were covalently modified with an adhesive oligopeptide, cyclic Arg-Gly-Asp (RGD) (ATQD-RGD). The mean height of the monolayer coating on the surfaces was approximately 3 nm, as measured by atomic force microscopy. The biocompatibility of the novel electroactive substrates was evaluated using PC12 pheochromocytoma cells, an established cell line of neural origin. The bioactive, derivatized electroactive scaffold material, ATQD-RGD, supported PC12 cell adhesion and proliferation, similar to control tissue-culture-treated polystyrene surfaces. Importantly, electroactive surfaces stimulated spontaneous neuritogenesis in PC12 cells, in the absence of neurotrophic growth factors, such as nerve growth factor (NGF). As expected, NGF significantly enhanced neurite extension on both control and electroactive surfaces. Taken together, our results suggest that the newly electroactive SAMs grafted with bioactive peptides, such as RGD, could be promising biomaterials for tissue engineering.

  2. Self-assembled high-strength hydroxyapatite/graphene oxide/chitosan composite hydrogel for bone tissue engineering.

    Science.gov (United States)

    Yu, Peng; Bao, Rui-Ying; Shi, Xiao-Jun; Yang, Wei; Yang, Ming-Bo

    2017-01-02

    Graphene hydrogel has shown greatly potentials in bone tissue engineering recently, but it is relatively weak in the practical use. Here we report a facile method to synthesize high strength composite graphene hydrogel. Graphene oxide (GO), hydroxyapatite (HA) nanoparticles (NPs) and chitosan (CS) self-assemble into a 3-dimensional hydrogel with the assistance of crosslinking agent genipin (GNP) for CS and reducing agent sodium ascorbate (NaVC) for GO simultaneously. The dense and oriented microstructure of the resulted composite gel endows it with high mechanical strength, high fixing capacity of HA and high porosity. These properties together with the good biocompatibility make the ternary composite gel a promising material for bone tissue engineering. Such a simultaneous crosslinking and reduction strategy can also be applied to produce a variety of 3D graphene-polymer based nanocomposites for biomaterials, energy storage materials and adsorbent materials. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. Design, construction and performance evaluation of the target tissue thickness measurement system in intraoperative radiotherapy for breast cancer

    Energy Technology Data Exchange (ETDEWEB)

    Yazdani, Mohammad Reza, E-mail: myazdani@aut.ac.ir [Faculty of Energy Engineering and Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Setayeshi, Saeed, E-mail: setayesh@aut.ac.ir [Faculty of Energy Engineering and Physics, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Arabalibeik, Hossein, E-mail: arabalibeik@tums.ac.ir [Research Center for Biomedical Technology and Robotics (RCBTR), Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Akbari, Mohammad Esmaeil [Cancer Research Center, Shahid Beheshti University of Medical Sciences, Tehran (Iran, Islamic Republic of)

    2017-05-21

    Intraoperative electron radiation therapy (IOERT), which uses electron beams for irradiating the target directly during the surgery, has the advantage of delivering a homogeneous dose to a controlled layer of tissue. Since the dose falls off quickly below the target thickness, the underlying normal tissues are spared. In selecting the appropriate electron energy, the accuracy of the target tissue thickness measurement is critical. In contrast to other procedures applied in IOERT, the routine measurement method is considered to be completely traditional and approximate. In this work, a novel mechanism is proposed for measuring the target tissue thickness with an acceptable level of accuracy. An electronic system has been designed and manufactured with the capability of measuring the tissue thickness based on the recorded electron density under the target. The results indicated the possibility of thickness measurement with a maximum error of 2 mm for 91.35% of data. Aside from system limitation in estimating the thickness of 5 mm phantom, for 88.94% of data, maximum error is 1 mm.

  4. Ultra-high vacuum target assembly for charged particle irradiations in the materials research field

    International Nuclear Information System (INIS)

    Bressers, J.; Cassanelli, G.; Cat, R. de; Kohnen, H.; Gherardi, G.

    1978-01-01

    A target assembly designed for ion irradiation and ion implantation experiments on different particle accelerators is described. It consists of a target chamber separated from the beam line by a thin metal window, thus allowing implantations to be carried out under ultra-high vacuum conditions. Homogeneous in-depth distribution of the implanted ion species is realized by rotating the target about an axis perpendicular to the ion beam (rocking). The target holder is driven by means of a stepping motor with a constant step angle and a rocking device controller containing the required rocking angle-dwell time relation. Ion beam homogeneity over a sufficiently large target area is arrived at by transforming the Gaussian beam intensity profile into a flat beam intensity distribution by means of an electrostatic ring lens. The beam intensity profile is monitored by means of a specially designed ion beam monitor based on the Nipkov disc principle. A toroidal beam current monitoring transformer continuously measures the total beam current. Beam scanners and current measuring collimators complete the beam analysing equipment

  5. Expression and function of NOD-like receptors by human term gestation-associated tissues.

    Science.gov (United States)

    Bryant, Aled H; Bevan, Ryan J; Spencer-Harty, Samantha; Scott, Louis M; Jones, Ruth H; Thornton, Catherine A

    2017-10-01

    Nucleotide-binding oligomerization domain (NOD)-like receptors or NOD-like receptors (NLRs) have been implicated in several disease pathologies associated with inflammation. Since local and systemic inflammation is a hallmark of both term and preterm labour, a role for NLRs at the materno-fetal interface has been postulated. Gene expression and immunolocalisation of NLR family members in human placenta, choriodecidua, and amnion were examined. Tissue explants were used to examine the response to activators of NOD1 (Tri-DAP), NOD2 (MDP) and NLRP3 (nigericin). Cell/tissue-free supernatants were examined for the production of interleukin (IL)-1β, IL-6, IL-8 and IL-10 using specific ELISAs. Expression of transcripts for NOD1, NOD2, NLRP3, NLRC4, NLRX1, NLRP1 and NAIP and protein expression of NOD1, NOD2 and NLRP3 were a broad feature of all term gestation-associated tissues. Production of cytokines was increased significantly in response to all ligands in placenta and choriodecidua, except for MDP-induced IL-10. Similarly, there was a significant in the amnion except for MDP induced IL-1β and IL-10 response to either agonist. IL-1β production was dependent on caspase-1 regardless of agonist used or tissue examined. Term human gestation-associated tissues express functional NLRs which likely play a role in both sterile and pathogen-driven inflammatory responses at the materno-fetal interface. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Cyp1a reporter zebrafish reveals target tissues for dioxin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kun-Hee [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Park, Hye-Jeong [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); Kim, Jin Hee [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Kim, Suhyun [Graduate School of Medicine, Korea University, Ansan (Korea, Republic of); Williams, Darren R. [New Drug Targets Laboratory, School of Life Sciences, Gwangju Institute of Science and Technology, Gwangju (Korea, Republic of); Kim, Myeong-Kyu [Department of Neurology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Jung, Young Do [Department of Biochemistry, Chonnam National University Medical School, Gwangju (Korea, Republic of); Teraoka, Hiroki [School of Veterinary Medicine, Rakuno Gakuen University, Ebetsu (Japan); Park, Hae-Chul [Graduate School of Medicine, Korea University, Ansan (Korea, Republic of); Choy, Hyon E., E-mail: hyonchoy@chonnam.ac.kr [Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Shin, Boo Ahn, E-mail: bashin@chonnam.ac.kr [Department of Microbiology, Chonnam National University Medical School, Gwangju (Korea, Republic of); Choi, Seok-Yong, E-mail: zebrafish@chonnam.ac.kr [Department of Biomedical Sciences, Chonnam National University Medical School, Gwangju (Korea, Republic of); School of Biological Sciences and Technology, Chonnam National University, Gwangju (Korea, Republic of)

    2013-06-15

    Highlights: •2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the most toxic anthropogenic substance ever identified. •Transgenic cyp1a reporter zebrafish reveals target tissues for TCDD. •The retinal bipolar cells, otic vesicle, lateral line, pancreas, cloaca and pectoral fin bud are novel targets in zebrafish for TCDD. •Our findings will further understanding of human health risks by TCDD. -- Abstract: 2,3,7,8-Tetrachlorodibenzo-p-dioxin (TCDD) is the unintentional byproduct of various industrial processes, is classified as human carcinogen and could disrupt reproductive, developmental and endocrine systems. Induction of cyp1a1 is used as an indicator of TCDD exposure. We sought to determine tissues that are vulnerable to TCDD toxicity using a transgenic zebrafish (Danio rerio) model. We inserted a nuclear enhanced green fluorescent protein gene (EGFP) into the start codon of a zebrafish cyp1a gene in a fosmid clone using DNA recombineering. The resulting recombineered fosmid was then used to generate cyp1a reporter zebrafish, embryos of which were exposed to TCDD. Expression pattern of EGFP in the reporter zebrafish mirrored that of endogenous cyp1a mRNA. In addition, exposure of the embryos to TCDD at as low as 10 pM for 72 h, which does not elicit morphological abnormalities of embryos, markedly increased GFP expression. Furthermore, the reporter embryos responded to other AhR ligands as well. Exposure of the embryos to TCDD revealed previously reported (the cardiovascular system, liver, pancreas, kidney, swim bladder and skin) and unreported target tissues (retinal bipolar cells, otic vesicle, lateral line, cloaca and pectoral fin bud) for TCDD. Transgenic cyp1a reporter zebrafish we have developed can further understanding of ecotoxicological relevance and human health risks by TCDD. In addition, they could be used to identify agonists of AhR and antidotes to TCDD toxicity.

  7. In vitro assembly into virus-like particles is an intrinsic quality of Pichia pastoris derived HCV core protein

    International Nuclear Information System (INIS)

    Acosta-Rivero, Nelson; Rodriguez, Armando; Musacchio, Alexis; Falcon, Viviana; Suarez, Viana M.; Martinez, Gillian; Guerra, Ivis; Paz-Lago, Dalila; Morera, Yanelys; Rosa, Maria C. de la; Morales-Grillo, Juan; Duenas-Carrera, Santiago

    2004-01-01

    Different variants of hepatitis C virus core protein (HCcAg) have proved to self-assemble in vitro into virus-like particles (VLPs). However, difficulties in obtaining purified mature HCcAg have limited these studies. In this study, a high degree of monomeric HCcAg purification was accomplished using chromatographic procedures under denaturing conditions. Size exclusion chromatography and sucrose density gradient centrifugation of renatured HCcAg (in the absence of structured RNA) under reducing conditions suggested that it assembled into empty capsids. The electron microscopy analysis of renatured HCcAg showed the presence of spherical VLPs with irregular shapes and an average diameter of 35 nm. Data indicated that HCcAg monomers assembled in vitro into VLPs in the absence of structured RNA, suggesting that recombinant HCcAg used in this work contains all the information necessary for the assembly process. However, they also suggest that some cellular factors might be required for the proper in vitro assembly of capsids

  8. Metformin Targets Brown Adipose Tissue in vivo and Reduces Oxygen Consumption in vitro

    DEFF Research Database (Denmark)

    Breining, Peter; Jensen, Jonas B; Sundelin, Elias I

    2018-01-01

    basic metabolic rate, making BAT an attractive target for treatment of type 2 diabetes. Under the hypothesis that BAT is a metformin target tissue, we investigated in vivo uptake of [11 C]-metformin tracer in mice and studied in vitro effects of metformin on cultured human brown adipocytes. Injected [11......Metformin is the most widely prescribed oral antidiabetic drug worldwide. Despite well-documented beneficial effects on health outcomes in diabetic patients, the target organs that mediate the effects of metformin remain to be established. In adult humans, brown adipose tissue (BAT) can influence...... uptake. Gene expression profiles of OCTs in BAT revealed ample OCT3 expression in both human and mouse BAT. Incubation of a human brown adipocyte cell models with metformin reduced cellular oxygen consumption in a dose dependent manner. Collectively, these results support BAT as a putative metformin...

  9. Intracellular targeting of CD44+ cells with self-assembling, protein only nanoparticles.

    Science.gov (United States)

    Pesarrodona, Mireia; Ferrer-Miralles, Neus; Unzueta, Ugutz; Gener, Petra; Tatkiewicz, Witold; Abasolo, Ibane; Ratera, Imma; Veciana, Jaume; Schwartz, Simó; Villaverde, Antonio; Vazquez, Esther

    2014-10-01

    CD44 is a multifunctional cell surface protein involved in proliferation and differentiation, angiogenesis and signaling. The expression of CD44 is up-regulated in several types of human tumors and particularly in cancer stem cells, representing an appealing target for drug delivery in the treatment of cancer. We have explored here several protein ligands of CD44 for the construction of self-assembling modular proteins designed to bind and internalize target cells. Among five tested ligands, two of them (A5G27 and FNI/II/V) drive the formation of protein-only, ring-shaped nanoparticles of about 14 nm that efficiently bind and penetrate CD44(+) cells by an endosomal route. The potential of these newly designed nanoparticles is evaluated regarding the need of biocompatible nanostructured materials for drug delivery in CD44-linked conditions. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Regulation of annexins following infection like tissue damage – investigated by 2-dimensional gel electrophoresis

    DEFF Research Database (Denmark)

    Wulff, Tune; Nielsen, Michael Engelbrecht

    are regulated after tissue damaged on the protein level. These proteins have been assign to functions like regulation of coagulation, apoptosis, and exocytosis, indicating their importance following infection and subsequent repair in fish. In addition the regulation observed in this study are supported...... an established model. In the model infection is mimicked by a well-defined tissue damage allowing each fish to be equally affected. Samples were taken 7 days after tissue damage and included samples from the damaged tissue, internal control and an external control. Changes in protein expression between the wound...... by previous findings on the mRNA level, where both proteins are regulated following infection. In conclusion this study show regulation on the protein level of two members of the annexin protein family after infection like tissue damage....

  11. Advanced cell culture technology for generation of in vivo-like tissue models

    Directory of Open Access Journals (Sweden)

    Stefan Przyborski

    2017-06-01

    Full Text Available Human tissues are mostly composed of different cell types, that are often highly organised in relation to each other. Often cells are arranged in distinct layers that enable signalling and cell-to-cell interactions. Here we describe the application of scaffold-based technology, that can be used to create advanced organotypic 3D models of various tissue types that more closely resemble in vivo-like conditions (Knight et al., 2011. The scaffold comprises a highly porous polystyrene material, engineered into a 200 micron thick membrane that is presented in various ways including multi-welled plates and well inserts, for use with conventional culture plasticware and medium perfusion systems. This technology has been applied to generate numerous unique types of co-culture model. For example: 1 a full thickness human skin construct comprising dermal fibroblasts and keratinocytes, raised to the air-liquid interface to induce cornification of the upper layers (Fig.1 (Hill et al., 2015; 2 a neuron-glial co-culture to enable the study of neurite outgrowth interacting with astroglial cells to model and investigate the glial scar found in spinal cord injury (Clarke et al., 2016; 3 formation of a sub-mucosa consisting of a polarised simple epithelium, layer of ECM proteins simulating the basement membrane, and underlying stromal tissues (e.g. intestinal mucosa. These organotypic models demonstrate the versatility of scaffold membranes and the creation of advanced in vivo-like tissue models. Creating a layered arrangement more closely simulates the true anatomy and organisation of cells within many tissue types. The addition of different cell types in a temporal and spatial fashion can be used to study inter-cellular relationships and create more physiologically relevant in vivo-like cell-based assays. Methods that are relatively straightforward to use and that recreate the organised structure of real tissues will become valuable research tools for use in

  12. SERS-barcoded colloidal gold NP assemblies as imaging agents for use in biodiagnostics

    Science.gov (United States)

    Dey, Priyanka; Olds, William; Blakey, Idriss; Thurecht, Kristofer J.; Izake, Emad L.; Fredericks, Peter M.

    2014-03-01

    There is a growing need for new biodiagnostics that combine high throughput with enhanced spatial resolution and sensitivity. Gold nanoparticle (NP) assemblies with sub-10 nm particle spacing have the benefits of improving detection sensitivity via Surface enhanced Raman scattering (SERS) and being of potential use in biomedicine due to their colloidal stability. A promising and versatile approach to form solution-stable NP assemblies involves the use of multi-branched molecular linkers which allows tailoring of the assembly size, hot-spot density and interparticle distance. We have shown that linkers with multiple anchoring end-groups can be successfully employed as a linker to assemble gold NPs into dimers, linear NP chains and clustered NP assemblies. These NP assemblies with diameters of 30-120 nm are stable in solution and perform better as SERS substrates compared with single gold NPs, due to an increased hot-spot density. Thus, tailored gold NP assemblies are potential candidates for use as biomedical imaging agents. We observed that the hot-spot density and in-turn the SERS enhancement is a function of the linker polymer concentration and polymer architecture. New deep Raman techniques like Spatially Offset Raman Spectroscopy (SORS) have emerged that allow detection from beneath diffusely scattering opaque materials, including biological media such as animal tissue. We have been able to demonstrate that the gold NP assemblies could be detected from within both proteinaceous and high lipid containing animal tissue by employing a SORS technique with a backscattered geometry.

  13. Use of magnetic forces to promote stem cell aggregation during differentiation, and cartilage tissue modeling.

    Science.gov (United States)

    Fayol, D; Frasca, G; Le Visage, C; Gazeau, F; Luciani, N; Wilhelm, C

    2013-05-14

    Magnetic forces induce cell condensation necessary for stem cell differentiation into cartilage and elicit the formation of a tissue-like structure: Magnetically driven fusion of aggregates assembled by micromagnets results in the formation of a continuous tissue layer containing abundant cartilage matrix. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Accordion-like honeycombs for tissue engineering of cardiac anisotropy

    Science.gov (United States)

    Engelmayr, George C.; Cheng, Mingyu; Bettinger, Christopher J.; Borenstein, Jeffrey T.; Langer, Robert; Freed, Lisa E.

    2008-12-01

    Tissue-engineered grafts may be useful in myocardial repair; however, previous scaffolds have been structurally incompatible with recapitulating cardiac anisotropy. Here, we use microfabrication techniques to create an accordion-like honeycomb microstructure in poly(glycerol sebacate), which yields porous, elastomeric three-dimensional (3D) scaffolds with controllable stiffness and anisotropy. Accordion-like honeycomb scaffolds with cultured neonatal rat heart cells demonstrated utility through: (1) closely matched mechanical properties compared to native adult rat right ventricular myocardium, with stiffnesses controlled by polymer curing time; (2) heart cell contractility inducible by electric field stimulation with directionally dependent electrical excitation thresholds (pthe formation of grafts with aligned heart cells and mechanical properties more closely resembling native myocardium.

  15. Self-Assembled Colloidal Particle Clusters from In Situ Pickering-Like Emulsion Polymerization via Single Electron Transfer Mechanism.

    Science.gov (United States)

    Yuan, Jinfeng; Zhao, Weiting; Pan, Mingwang; Zhu, Lei

    2016-08-01

    A simple route is reported to synthesize colloidal particle clusters (CPCs) from self-assembly of in situ poly(vinylidene fluoride)/poly(styrene-co-tert-butyl acrylate) [PVDF/P(St-co-tBA)] Janus particles through one-pot seeded emulsion single electron transfer radical polymerization. In the in situ Pickering-like emulsion polymerization, the tBA/St/PVDF feed ratio and polymerization temperature are important for the formation of well-defined CPCs. When the tBA/St/PVDF feed ratio is 0.75 g/2.5 g/0.5 g and the reaction temperature is 35 °C, relatively uniform raspberry-like CPCs are obtained. The hydrophobicity of the P(St-co-tBA) domains and the affinity of PVDF to the aqueous environment are considered to be the driving force for the self-assembly of the in situ formed PVDF/P(St-co-tBA) Janus particles. The resultant raspberry-like CPCs with PVDF particles protruding outward may be promising for superhydrophobic smart coatings. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. De novo Transcriptome Assembly of Chinese Kale and Global Expression Analysis of Genes Involved in Glucosinolate Metabolism in Multiple Tissues

    Science.gov (United States)

    Wu, Shuanghua; Lei, Jianjun; Chen, Guoju; Chen, Hancai; Cao, Bihao; Chen, Changming

    2017-01-01

    Chinese kale, a vegetable of the cruciferous family, is a popular crop in southern China and Southeast Asia due to its high glucosinolate content and nutritional qualities. However, there is little research on the molecular genetics and genes involved in glucosinolate metabolism and its regulation in Chinese kale. In this study, we sequenced and characterized the transcriptomes and expression profiles of genes expressed in 11 tissues of Chinese kale. A total of 216 million 150-bp clean reads were generated using RNA-sequencing technology. From the sequences, 98,180 unigenes were assembled for the whole plant, and 49,582~98,423 unigenes were assembled for each tissue. Blast analysis indicated that a total of 80,688 (82.18%) unigenes exhibited similarity to known proteins. The functional annotation and classification tools used in this study suggested that genes principally expressed in Chinese kale, were mostly involved in fundamental processes, such as cellular and molecular functions, the signal transduction, and biosynthesis of secondary metabolites. The expression levels of all unigenes were analyzed in various tissues of Chinese kale. A large number of candidate genes involved in glucosinolate metabolism and its regulation were identified, and the expression patterns of these genes were analyzed. We found that most of the genes involved in glucosinolate biosynthesis were highly expressed in the root, petiole, and in senescent leaves. The expression patterns of ten glucosinolate biosynthetic genes from RNA-seq were validated by quantitative RT-PCR in different tissues. These results provided an initial and global overview of Chinese kale gene functions and expression activities in different tissues. PMID:28228764

  17. Engineering β-sheet peptide assemblies for biomedical applications.

    Science.gov (United States)

    Yu, Zhiqiang; Cai, Zheng; Chen, Qiling; Liu, Menghua; Ye, Ling; Ren, Jiaoyan; Liao, Wenzhen; Liu, Shuwen

    2016-03-01

    Hydrogels have been widely studied in various biomedical applications, such as tissue engineering, cell culture, immunotherapy and vaccines, and drug delivery. Peptide-based nanofibers represent a promising new strategy for current drug delivery approaches and cell carriers for tissue engineering. This review focuses on the recent advances in the use of self-assembling engineered β-sheet peptide assemblies for biomedical applications. The applications of peptide nanofibers in biomedical fields, such as drug delivery, tissue engineering, immunotherapy, and vaccines, are highlighted. The current challenges and future perspectives for self-assembling peptide nanofibers in biomedical applications are discussed.

  18. Hypoxia-Inducible Factors: Mediators of Cancer Progression; Prognostic and Therapeutic Targets in Soft Tissue Sarcomas

    International Nuclear Information System (INIS)

    Sadri, Navid; Zhang, Paul J.

    2013-01-01

    Soft-tissue sarcomas remain aggressive tumors that result in death in greater than a third of patients due to either loco-regional recurrence or distant metastasis. Surgical resection remains the main choice of treatment for soft tissue sarcomas with pre- and/or post-operational radiation and neoadjuvant chemotherapy employed in more advanced stage disease. However, in recent decades, there has been little progress in the average five-year survival for the majority of patients with high-grade soft tissue sarcomas, highlighting the need for improved targeted therapeutic agents. Clinical and preclinical studies demonstrate that tumor hypoxia and up-regulation of hypoxia-inducible factors (HIFs) is associated with decreased survival, increased metastasis, and resistance to therapy in soft tissue sarcomas. HIF-mediated gene expression regulates many critical aspects of tumor biology, including cell survival, metabolic programming, angiogenesis, metastasis, and therapy resistance. In this review, we discuss HIFs and HIF-mediated genes as potential prognostic markers and therapeutic targets in sarcomas. Many pharmacological agents targeting hypoxia-related pathways are in development that may hold therapeutic potential for treating both primary and metastatic sarcomas that demonstrate increased HIF expression

  19. Thermal contribution of compact bone to intervening tissue-like media exposed to planar ultrasound

    Energy Technology Data Exchange (ETDEWEB)

    Moros, Eduardo G [Department of Radiation Oncology, Washington University, St Louis, MO 63108 (United States); Novak, Petr [Department of Radiation Oncology, Washington University, St Louis, MO 63108 (United States); Straube, William L [Department of Radiation Oncology, Washington University, St Louis, MO 63108 (United States); Kolluri, Prashant [Department of Radiation Oncology, Washington University, St Louis, MO 63108 (United States); Yablonskiy, Dmitriy A [Department of Radiology, Washington University, St Louis, MO 63108 (United States); Myerson, Robert J [Department of Radiation Oncology, Washington University, St Louis, MO 63108 (United States)

    2004-03-21

    The presence of bone in the ultrasound beam path raises concerns, both in diagnostic and therapeutic applications, because significant temperature elevations may be induced at nearby soft tissue-bone interfaces due the facts that ultrasound is (i) highly absorbed in bone and (ii) reflected at soft tissue-bone interfaces in various degrees depending on angle of incidence. Consequently, in ultrasonic thermal therapy, the presence of bone in the ultrasound beam path is considered a major disadvantage and it is usually avoided. However, based on clinical experience and previous theoretical studies, we hypothesized that the presence of bone in superficial unfocused ultrasound hyperthermia can actually be exploited to induce more uniform and enhanced (with respect to the no-bone situation) temperature distributions in superficial target volumes. In particular, we hypothesize that the presence of underlying bone in superficial target volume enhances temperature elevation not only by additional direct power deposition from acoustic reflection, but also from thermal diffusion from the underlying bone. Here we report laboratory results that corroborate previous computational studies and strengthen the above-stated hypothesis. Three different temperature measurement techniques, namely, thermometric (using fibre-optic temperature probes), thermographic (using an infrared camera) and magnetic resonance imaging (using proton resonance frequency shifts), were used in high-power short-exposure, and in low-power extended-exposure, experiments using a 19 mm diameter planar transducer operating at 1.0 and 3.3 MHz (frequencies of clinical relevance). The measurements were performed on three technique-specific phantoms (with and without bone inclusions) and experimental set-ups that resembled possible superficial ultrasound hyperthermia clinical situations. Results from all three techniques were in general agreement and clearly showed that significantly higher heating rates (greater

  20. Polymeric micelles for drug targeting.

    Science.gov (United States)

    Mahmud, Abdullah; Xiong, Xiao-Bing; Aliabadi, Hamidreza Montazeri; Lavasanifar, Afsaneh

    2007-11-01

    Polymeric micelles are nano-delivery systems formed through self-assembly of amphiphilic block copolymers in an aqueous environment. The nanoscopic dimension, stealth properties induced by the hydrophilic polymeric brush on the micellar surface, capacity for stabilized encapsulation of hydrophobic drugs offered by the hydrophobic and rigid micellar core, and finally a possibility for the chemical manipulation of the core/shell structure have made polymeric micelles one of the most promising carriers for drug targeting. To date, three generations of polymeric micellar delivery systems, i.e. polymeric micelles for passive, active and multifunctional drug targeting, have arisen from research efforts, with each subsequent generation displaying greater specificity for the diseased tissue and/or targeting efficiency. The present manuscript aims to review the research efforts made for the development of each generation and provide an assessment on the overall success of polymeric micellar delivery system in drug targeting. The emphasis is placed on the design and development of ligand modified, stimuli responsive and multifunctional polymeric micelles for drug targeting.

  1. Data on cytochrome c oxidase assembly in mice and human fibroblasts or tissues induced by SURF1 defect

    Directory of Open Access Journals (Sweden)

    Nikola Kovářová

    2016-06-01

    Full Text Available This paper describes data related to a research article entitled “Tissue- and species-specific differences in cytochrome c oxidase assembly induced by SURF1 defects” [1]. This paper includes data of the quantitative analysis of individual forms of respiratory chain complexes I, III and IV present in SURF1 knockout (SURF1−/− and control (SURF1+/+ mouse fibroblasts and tissues and in fibroblasts of human control and patients with SURF1 gene mutation. Also it includes data demonstrating response of complex IV, cytochrome c oxidase (COX, to reversible inhibition of mitochondrial translation in SURF1−/− mouse and SURF1 patient fibroblast cell lines.

  2. Targeted Editing of Myostatin Gene in Sheep by Transcription Activator-like Effector Nucleases

    Directory of Open Access Journals (Sweden)

    Xinxia Zhao

    2016-03-01

    Full Text Available Myostatin (MSTN is a secreted growth factor expressed in skeletal muscle and adipose tissue that negatively regulates skeletal muscle mass. Gene knockout of MSTN can result in increasing muscle mass in sheep. The objectives were to investigate whether myostatin gene can be edited in sheep by transcription activator-like effector nucleases (TALENs in tandem with single-stranded DNA oligonucleotides (ssODNs. We designed a pair of TALENs to target a highly conserved sequence in the coding region of the sheep MSTN gene. The activity of the TALENs was verified by using luciferase single-strand annealing reporter assay in HEK 293T cell line. Co-transfection of TALENs and ssODNs oligonucleotides induced precise gene editing of myostatin gene in sheep primary fibroblasts. MSTN gene-edited cells were successfully used as nuclear donors for generating cloned embryos. TALENs combined with ssDNA oligonucleotides provide a useful approach for precise gene modification in livestock animals.

  3. Simulated nuclear reactor fuel assembly

    International Nuclear Information System (INIS)

    Berta, V.T.

    1993-01-01

    An apparatus for electrically simulating a nuclear reactor fuel assembly. It includes a heater assembly having a top end and a bottom end and a plurality of concentric heater tubes having electrical circuitry connected to a power source, and radially spaced from each other. An outer target tube and an inner target tube is concentric with the heater tubes and with each other, and the outer target tube surrounds and is radially spaced from the heater tubes. The inner target tube is surrounded by and radially spaced from the heater tubes and outer target tube. The top of the assembly is generally open to allow for the electrical power connection to the heater tubes, and the bottom of the assembly includes means for completing the electrical circuitry in the heater tubes to provide electrical resistance heating to simulate the power profile in a nuclear reactor. The embedded conductor elements in each heater tube is split into two halves for a substantial portion of its length and provided with electrical isolation such that each half of the conductor is joined at one end and is not joined at the other end

  4. Engineered cartilaginous tubes for tracheal tissue replacement via self-assembly and fusion of human mesenchymal stem cell constructs.

    Science.gov (United States)

    Dikina, Anna D; Strobel, Hannah A; Lai, Bradley P; Rolle, Marsha W; Alsberg, Eben

    2015-06-01

    There is a critical need to engineer a neotrachea because currently there are no long-term treatments for tracheal stenoses affecting large portions of the airway. In this work, a modular tracheal tissue replacement strategy was developed. High-cell density, scaffold-free human mesenchymal stem cell-derived cartilaginous rings and tubes were successfully generated through employment of custom designed culture wells and a ring-to-tube assembly system. Furthermore, incorporation of transforming growth factor-β1-delivering gelatin microspheres into the engineered tissues enhanced chondrogenesis with regard to tissue size and matrix production and distribution in the ring- and tube-shaped constructs, as well as luminal rigidity of the tubes. Importantly, all engineered tissues had similar or improved biomechanical properties compared to rat tracheas, which suggests they could be transplanted into a small animal model for airway defects. The modular, bottom up approach used to grow stem cell-based cartilaginous tubes in this report is a promising platform to engineer complex organs (e.g., trachea), with control over tissue size and geometry, and has the potential to be used to generate autologous tissue implants for human clinical applications. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Advanced cell culture technology for generation of in vivo-like tissue models

    OpenAIRE

    Przyborski, Stefan

    2017-01-01

    Human tissues are mostly composed of different cell types, that are often highly organised in relation to each other. Often cells are arranged in distinct layers that enable signalling and cell-to-cell interactions. Here we describe the application of scaffold-based technology, that can be used to create advanced organotypic 3D models of various tissue types that more closely resemble in vivo-like conditions (Knight et al., 2011). The scaffold comprises a highly porous polystyrene material, e...

  6. Discrimination between landmine and mine-like targets using wavelets and spectral analysis

    Directory of Open Access Journals (Sweden)

    Mahmoud A. Mohana

    2013-06-01

    Ground penetrating radar (GPR is a powerful and non-destructive geophysical approach with a wide range of advantages in the field of landmine inspection. In the present paper, we apply different simulation models with Vivaldi antenna and mine-like targets by using the CST Microwave studio program. The field work is carried out by using a GPR device of model SIR 2000 from GSSI (Geophysical Survey Systems Incorporation connected to 900 MHz antenna where the targets were buried in sand soil. Depending on the fact that the receiving powers (reflected, refracted and scattered from the different materials are different, we study the spectral power densities for the received power from the different targets. The techniques used in this study are: direct fast Fourier transform, short time Fourier transform (spectrogram, wavelets transform and denoising techniques. Our results ought to be considered as finger prints for different scanned targets during this work. So we can discriminate between landmines and mine-like targets.

  7. Elastin-Like Recombinamers As Smart Drug Delivery Systems.

    Science.gov (United States)

    Arias, F Javier; Santos, Mercedes; Ibanez-Fonseca, Arturo; Pina, Maria Jesus; Serrano, Sofía

    2018-02-19

    Drug delivery systems that are able to control the release of bioactive molecules and designed to carry drugs to target sites are of particular interest for tissue therapy. Moreover, systems comprising materials that can respond to environmental stimuli and promote self-assembly and higher order supramolecular organization are especially useful in the biomedical field. Objetive: This review focuses on biomaterials suitable for this purpose and that include elastin-like recombinamers (ELRs), a class of proteinaceous polymers bioinspired by natural elastin, designed using recombinant technologies. The self-assembly and thermoresponsive behaviour of these systems, along with their biodegradability, biocompatibility and well-defined composition as a result of their tailormade design, make them particularly attractive for controlled drug delivery. ELR-based delivery systems that allow targeted delivery are reviewed, especially ELR-drug recombinant fusion constructs, ELR-drug systems chemically bioconjugated in their monomeric and soluble forms, and drug encapsulation by nanoparticle-forming ELRs. Subsequently, the review focuses on those drug carriers in which smart release is triggered by pH or temperature with a particular focus on cancer treatments. Systems for controlled drug release based on depots and hydrogels that act as both a support and reservoir in which drugs can be stored will be described, and their applications in drug delivery discussed. Finally, smart drug-delivery systems not based on ELRs, including those comprising proteins, synthetic polymers and non-polymeric systems, will also be briefly discussed. Several different constructions based on ELRs are potential candidates for controlled drug delivery to be applied in advanced biomedical treatments. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  8. Structure formation of lipid membranes: Membrane self-assembly and vesicle opening-up to octopus-like micelles

    Science.gov (United States)

    Noguchi, Hiroshi

    2013-02-01

    We briefly review our recent studies on self-assembly and vesicle rupture of lipid membranes using coarse-grained molecular simulations. For single component membranes, lipid molecules self-assemble from random gas states to vesicles via disk-shaped clusters. Clusters aggregate into larger clusters, and subsequently the large disks close into vesicles. The size of vesicles are determined by kinetics than by thermodynamics. When a vesicle composed of lipid and detergent types of molecules is ruptured, a disk-shaped micelle called bicelle can be formed. When both surfactants have negligibly low critical micelle concentration, it is found that bicelles connected with worm-like micelles are also formed depending on the surfactant ratio and spontaneous curvature of the membrane monolayer.

  9. Flower-like self-assembly of gold nanoparticles for highly sensitive electrochemical detection of chromium(VI)

    International Nuclear Information System (INIS)

    Ouyang Ruizhuo; Bragg, Stefanie A.; Chambers, James Q.; Xue Ziling

    2012-01-01

    Highlights: ► Fabrication of a flower-like self-assembly of two AuNP layers on a GCE. ► Cr(VI) detection: 10–1200 ng L −1 concentration range; 2.9 ng L −1 detection limit. ► The 1st AuNP layer on the GCE surface as anchors for a thiol sol–gel film. ► The sol–gel film link the 1st AuNP layer to the 2nd AuNP layer. ► Functionalization of the 2nd AuNP layer by a thiol pyridinium for HCrO 4 − detection. - Abstract: We report here the fabrication of a flower-like self-assembly of gold nanoparticles (AuNPs) on a glassy carbon electrode (GCE) as a highly sensitive platform for ultratrace Cr(VI) detection. Two AuNP layers are used in the current approach, in which the first is electroplated on the GCE surface as anchors for binding to an overcoated thiol sol–gel film derived from 3-mercaptopropyltrimethoxysilane (MPTS). The second AuNP layer is then self-assembled on the surface of the sol–gel film, forming flower-like gold nanoelectrodes enlarging the electrode surface. When functionalized by a thiol pyridinium, the fabricated electrode displays a well-defined peak for selective Cr(VI) reduction with an unusually large, linear concentration range of 10–1200 ng L −1 and a low detection limit of 2.9 ng L −1 . In comparison to previous approaches using MPTS and AuNPs on Au electrodes, the current work expands the use of AuNPs to the GCE. Subsequent functionalization of the secondary AuNPs by a thiol pyridinium and adsorption/preconcentration of Cr(VI) lead to the unusually large detection range and high sensitivity. The stepwise preparation of the electrode has been characterized by electrochemical impedance spectroscopy (EIS), scanning electronic microscopy (SEM), and IR. The newly designed electrode exhibits good stability, and has been successfully employed to measure chromium in a pre-treated blood sample. The method demonstrates acceptable fabrication reproducibility and accuracy.

  10. Controlled synthesis of pompon-like self-assemblies of Pd nanoparticles under microwave irradiation

    International Nuclear Information System (INIS)

    Tong Xia; Zhao Yanxi; Huang Tao; Liu Hanfan; Liew, Kong Yong

    2009-01-01

    Pd nanoparticles with uniform, self-assembled pompon-like nanostructure were synthesized by thermal decomposition of palladium acetate under microwave irradiation with methyl isobutyl ketone (MIBK) as a solvent in the presence of a little amount of ethylene glycol (EG) and KOH without using any special stabilizers. The as-synthesized Pd nano-pompons were characterized by transmission electron microscopy, X-ray photoelectron spectroscopy and X-ray powder diffraction. The results show that the as-prepared Pd nano-pompons with the average diameters in the range of 28-81 nm were self-assemblies organized by hundreds of smaller primary nanoparticles with an average dimension of about 2.4 nm. The sizes of Pd nano-pompons can be well controlled by adjusting the concentration of palladium acetate. A little amount of EG and KOH also plays an important role in controlling the size, uniformity and dispersion of Pd nano-pompons. The Pd nano-pompons can be easily supported on γ-Al 2 O 3 and their catalytic activity was examined preliminarily.

  11. DMPD: Toll-like receptors: novel pharmacological targets for the treatment ofneurological diseases. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17974478 Toll-like receptors: novel pharmacological targets for the treatment ofneu...png) (.svg) (.html) (.csml) Show Toll-like receptors: novel pharmacological targets for the treatment ofneur...ological diseases. PubmedID 17974478 Title Toll-like receptors: novel pharmacological target

  12. The carbohydrate-binding module (CBM)-like sequence is crucial for rice CWA1/BC1 function in proper assembly of secondary cell wall materials.

    Science.gov (United States)

    Sato, Kanna; Ito, Sachiko; Fujii, Takeo; Suzuki, Ryu; Takenouchi, Sachi; Nakaba, Satoshi; Funada, Ryo; Sano, Yuzou; Kajita, Shinya; Kitano, Hidemi; Katayama, Yoshihiro

    2010-11-01

    We recently reported that the cwa1 mutation disturbed the deposition and assembly of secondary cell wall materials in the cortical fiber of rice internodes. Genetic analysis revealed that cwa1 is allelic to bc1, which encodes glycosylphosphatidylinositol (GPI)-anchored COBRA-like protein with the highest homology to Arabidopsis COBRA-like 4 (COBL4) and maize Brittle Stalk 2 (Bk2). Our results suggested that CWA1/BC1 plays a role in assembling secondary cell wall materials at appropriate sites, enabling synthesis of highly ordered secondary cell wall structure with solid and flexible internodes in rice. The N-terminal amino acid sequence of CWA1/BC1, as well as its orthologs (COBL4, Bk2) and other BC1-like proteins in rice, shows weak similarity to a family II carbohydrate-binding module (CBM2) of several bacterial cellulases. To investigate the importance of the CBM-like sequence of CWA1/BC1 in the assembly of secondary cell wall materials, Trp residues in the CBM-like sequence, which is important for carbohydrate binding, were substituted for Val residues and introduced into the cwa1 mutant. CWA1/BC1 with the mutated sequence did not complement the abnormal secondary cell walls seen in the cwa1 mutant, indicating that the CBM-like sequence is essential for the proper function of CWA1/BC1, including assembly of secondary cell wall materials.

  13. MicroRNA-375 Inhibits Growth and Enhances Radiosensitivity in Oral Squamous Cell Carcinoma by Targeting Insulin Like Growth Factor 1 Receptor

    Directory of Open Access Journals (Sweden)

    Bin Zhang

    2017-08-01

    Full Text Available Background: MicroRNAs (miRNAs have emerged as key players in various human biological processes, including tumorigenesis. Here, we investigated the roles of miR-375 in the pathogenesis of oral squamous cell carcinoma (OSCC. Methods: We performed quantitative real-time PCR (qRT-PCR to detect miR-375 expression in OSCC tissues and corresponding normal oral epithelial tissues and analyze the correlation of miR-375 expression with OSCC metastasis and patient’s survival. Then, the effects of miR-375 expression on proliferation, cell cycle, apoptosis and radiosensitivity in OSCC cells were determined by using MTT, flow cytometry and clonogenic survival assays. A dual-luciferase reporter assay was performed to test whether miR-375 binds to the 3’-untranslated region (3’-UTR of target mRNA. Results: The expression level of miR-375 in OSCC tissues was significantly lower than that in normal oral epithelial tissues, and low miR-375 expression was correlated with higher incidence of lymph node metastasis and poor survival of OSCC patients. Upregulation of miR-375 significantly inhibits growth, induces cell cycle arrest in G0/G1 phase, increases apoptosis and enhances radiosensitivity in OSCC cells. Analysis of luciferase activity demonstrated that miR-375 binds to the 3’-UTR of insulin like growth factor 1 receptor (IGF-1R. Small interfering RNA (shRNA-mediated IGF-1R knockdown mimics the effects of miR-375 upregulation, while overexpression of IGF-1R partially reverses those effects in OSCC cells. Conclusion: It was obviously demonstrated that miRNA-375 inhibits growth and enhances radiosensitivity in OSCC cells by targeting IGF-1R, suggesting that miR-375 may be a potential therapeutic target for OSCC patients.

  14. Damage of target edges in brush-like geometry in the course of ELM-like plasma pulses in QSPA Kh-50

    Science.gov (United States)

    Makhlaj, V. A.; Garkusha, I. E.; Aksenov, N. N.; Bazylev, B.; Byrka, O. V.; Chebotarev, V. V.; Landman, I.; Herashchenko, S. S.; Staltsov, V. V.

    2015-08-01

    Castellated edges of macro-brush armour elements of ITER divertor can be a source of molten/solid dust particles which are injected into the plasma. The targets that combined in brush-like geometry have been irradiated under different inclination angles in QSPA Kh-50. The cubic brushes element has typical size of 1 cm. The titanium was used to investigate dynamics of mountains' formation. The onset of dust particles ejection from the exposed castellated targets has been studied. Formation of resolidified bridges through the gaps of brush-like targets due to the melt motion is studied in dynamics. With following plasma impacts such resolidified bridges became additional source of dust.

  15. Damage of target edges in brush-like geometry in the course of ELM-like plasma pulses in QSPA Kh-50

    International Nuclear Information System (INIS)

    Makhlaj, V.A.; Garkusha, I.E.; Aksenov, N.N.; Bazylev, B.; Byrka, O.V.; Chebotarev, V.V.; Landman, I.; Herashchenko, S.S.; Staltsov, V.V.

    2015-01-01

    Castellated edges of macro-brush armour elements of ITER divertor can be a source of molten/solid dust particles which are injected into the plasma. The targets that combined in brush-like geometry have been irradiated under different inclination angles in QSPA Kh-50. The cubic brushes element has typical size of 1 cm. The titanium was used to investigate dynamics of mountains’ formation. The onset of dust particles ejection from the exposed castellated targets has been studied. Formation of resolidified bridges through the gaps of brush-like targets due to the melt motion is studied in dynamics. With following plasma impacts such resolidified bridges became additional source of dust

  16. Damage of target edges in brush-like geometry in the course of ELM-like plasma pulses in QSPA Kh-50

    Energy Technology Data Exchange (ETDEWEB)

    Makhlaj, V.A., E-mail: makhlay@ipp.kharkov.ua [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine); Garkusha, I.E.; Aksenov, N.N. [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine); Bazylev, B. [Karlsruhe Institute of Technology (KIT), IHM, 76344 Karlsruhe (Germany); Byrka, O.V.; Chebotarev, V.V. [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine); Landman, I. [Karlsruhe Institute of Technology (KIT), IHM, 76344 Karlsruhe (Germany); Herashchenko, S.S.; Staltsov, V.V. [Institute of Plasma Physics of the NSC KIPT, 61108 Kharkov (Ukraine)

    2015-08-15

    Castellated edges of macro-brush armour elements of ITER divertor can be a source of molten/solid dust particles which are injected into the plasma. The targets that combined in brush-like geometry have been irradiated under different inclination angles in QSPA Kh-50. The cubic brushes element has typical size of 1 cm. The titanium was used to investigate dynamics of mountains’ formation. The onset of dust particles ejection from the exposed castellated targets has been studied. Formation of resolidified bridges through the gaps of brush-like targets due to the melt motion is studied in dynamics. With following plasma impacts such resolidified bridges became additional source of dust.

  17. Identifying SARS-CoV membrane protein amino acid residues linked to virus-like particle assembly.

    Directory of Open Access Journals (Sweden)

    Ying-Tzu Tseng

    Full Text Available Severe acute respiratory syndrome coronavirus (SARS-CoV membrane (M proteins are capable of self-assembly and release in the form of membrane-enveloped vesicles, and of forming virus-like particles (VLPs when coexpressed with SARS-CoV nucleocapsid (N protein. According to previous deletion analyses, M self-assembly involves multiple M sequence regions. To identify important M amino acid residues for VLP assembly, we coexpressed N with multiple M mutants containing substitution mutations at the amino-terminal ectodomain, carboxyl-terminal endodomain, or transmembrane segments. Our results indicate that a dileucine motif in the endodomain tail (218LL219 is required for efficient N packaging into VLPs. Results from cross-linking VLP analyses suggest that the cysteine residues 63, 85 and 158 are not in close proximity to the M dimer interface. We noted a significant reduction in M secretion due to serine replacement for C158, but not for C63 or C85. Further analysis suggests that C158 is involved in M-N interaction. In addition to mutations of the highly conserved 107-SWWSFNPE-114 motif, substitutions at codons W19, W57, P58, W91, Y94 or F95 all resulted in significantly reduced VLP yields, largely due to defective M secretion. VLP production was not significantly affected by a tryptophan replacement of Y94 or F95 or a phenylalanine replacement of W19, W57 or W91. Combined, these results indicate the involvement of specific M amino acids during SARS-CoV virus assembly, and suggest that aromatic residue retention at specific positions is critical for M function in terms of directing virus assembly.

  18. Characterization of alendronic- and undecylenic acid coated magnetic nanoparticles for the targeted delivery of rosiglitazone to subcutaneous adipose tissue.

    Science.gov (United States)

    Saatchi, Katayoun; Tod, Sarah E; Leung, Donna; Nicholson, Kenton E; Andreu, Irene; Buchwalder, Christian; Schmitt, Veronika; Häfeli, Urs O; Gray, Sarah L

    2017-02-01

    Obesity is a state of positive energy balance where excess white adipose tissue accumulates to the detriment of metabolic health. Improving adipocyte function with systemic administration of thiazolidinediones (TZDs) improves metabolic outcomes in obesity, however TZD use is limited clinically due to undesirable side effects. Here we evaluate magnetic nanoparticles (MNPs) as a tool to target rosiglitazone (Rosi) specifically to adipose tissue. Results show Rosi can be adsorbed to MNPs (Rosi-MNPs) with hydrophobic coatings for which we present binding and release kinetics. Rosi adsorbed to MNPs retained the ability to induce PPARγ target gene expression in cells. Biodistribution analysis of radiolabeled Rosi-MNPs revealed a fat-implanted magnet significantly enhanced localization of Rosi to the targeted adipose tissue when administered by subcutaneous injection to obese mice. We propose MNPs for targeted delivery of anti-diabetic agents to superficially located subcutaneous adipose tissue. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Pt supported self-assembled nest-like-porous WO3 hierarchical microspheres as electrocatalyst for methanol oxidation

    International Nuclear Information System (INIS)

    Zhang, Jun; Tu, Jiang-ping; Du, Gao-hui; Dong, Zi-min; Su, Qing-mei; Xie, Dong; Wang, Xiu-li

    2013-01-01

    Highlights: ► Nest-like-porous (NLP) WO 3 microspheres are assembled by a hydrothermal method. ► The NLP-WO 3 microspheres have a hexagonal structure and high porous surface. ► Great enhancement of electrochemical property is achieved for Pt/NLP-WO 3 microspheres. -- Abstract: Hexagonal tungsten trioxide (hex-WO 3 ) hierarchical microspheres with nest-like pores are synthesized by a facile hydrothermal method. The nest-like-porous (NLP) WO 3 hierarchical microspheres with 5–6 μm in diameters are self-assembled of single-crystal nanowires. The nanowires have lengths of several hundred nanometers and diameters of 5–30 nm; the long axis of nanowire is oriented toward 〈0 0 1〉 direction. The specific surface area of hex-WO 3 microspheres is 62 m 2 g −1 . 20 wt.% Pt nanoparticles with ∼7 nm are loaded onto the WO 3 microspheres using a conventional microwave-assisted ethylene glycol (EG) method. The electrocatalytic activity for methanol oxidation of Pt/NLP-WO 3 microspheres is investigated by cyclic voltammetry and chronoamperometry. Due to the large tunnels of hexagonal structure and high porous surface morphology, great enhancement of electrochemical performance is achieved. The Pt/NLP-WO 3 microspheres are demonstrated to be a promising anode material for direct methanol fuel cells (DMFC)

  20. Chain-like nanostructures from anisotropic self-assembly of semiconducting metal oxide nanoparticles with a block copolymer.

    Science.gov (United States)

    Wang, Junzheng; Winardi, Suminto; Sugawara-Narutaki, Ayae; Kumamoto, Akihito; Tohei, Tetsuya; Shimojima, Atsushi; Okubo, Tatsuya

    2012-11-21

    A facile method is reported for the preparation of chain-like nanostructures by anisotropic self-assembly of TiO(2) and SnO(2) nanoparticles with the aid of a block copolymer in an aqueous medium. Well-defined crystallographic orientations between neighbouring nanoparticles are observed in TiO(2) nanochains, which is important for tailoring the grain boundaries and thus enhancing charge transport.

  1. Assembly of cells and vesicles for organ engineering

    International Nuclear Information System (INIS)

    Taguchi, Tetsushi

    2011-01-01

    The development of materials and technologies for the assembly of cells and/or vesicles is a key for the next generation of tissue engineering. Since the introduction of the tissue engineering concept in 1993, various types of scaffolds have been developed for the regeneration of connective tissues in vitro and in vivo. Cartilage, bone and skin have been successfully regenerated in vitro, and these regenerated tissues have been applied clinically. However, organs such as the liver and pancreas constitute numerous cell types, contain small amounts of extracellular matrix, and are highly vascularized. Therefore, organ engineering will require the assembly of cells and/or vesicles. In particular, adhesion between cells/vesicles will be required for regeneration of organs in vitro. This review introduces and discusses the key technologies and materials for the assembly of cells/vesicles for organ regeneration. (topical review)

  2. Multi-scale coarse-graining for the study of assembly pathways in DNA-brick self-assembly

    Science.gov (United States)

    Fonseca, Pedro; Romano, Flavio; Schreck, John S.; Ouldridge, Thomas E.; Doye, Jonathan P. K.; Louis, Ard A.

    2018-04-01

    Inspired by recent successes using single-stranded DNA tiles to produce complex structures, we develop a two-step coarse-graining approach that uses detailed thermodynamic calculations with oxDNA, a nucleotide-based model of DNA, to parametrize a coarser kinetic model that can reach the time and length scales needed to study the assembly mechanisms of these structures. We test the model by performing a detailed study of the assembly pathways for a two-dimensional target structure made up of 334 unique strands each of which are 42 nucleotides long. Without adjustable parameters, the model reproduces a critical temperature for the formation of the assembly that is close to the temperature at which assembly first occurs in experiments. Furthermore, the model allows us to investigate in detail the nucleation barriers and the distribution of critical nucleus shapes for the assembly of a single target structure. The assembly intermediates are compact and highly connected (although not maximally so), and classical nucleation theory provides a good fit to the height and shape of the nucleation barrier at temperatures close to where assembly first occurs.

  3. Protein-like Nanoparticles Based on Orthogonal Self-Assembly of Chimeric Peptides.

    Science.gov (United States)

    Jiang, Linhai; Xu, Dawei; Namitz, Kevin E; Cosgrove, Michael S; Lund, Reidar; Dong, He

    2016-10-01

    A novel two-component self-assembling chimeric peptide is designed where two orthogonal protein folding motifs are linked side by side with precisely defined position relative to one another. The self-assembly is driven by a combination of symmetry controlled molecular packing, intermolecular interactions, and geometric constraint to limit the assembly into compact dodecameric protein nanoparticles. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Connective tissue growth factor as a novel therapeutic target in high grade serous ovarian cancer.

    Science.gov (United States)

    Moran-Jones, Kim; Gloss, Brian S; Murali, Rajmohan; Chang, David K; Colvin, Emily K; Jones, Marc D; Yuen, Samuel; Howell, Viive M; Brown, Laura M; Wong, Carol W; Spong, Suzanne M; Scarlett, Christopher J; Hacker, Neville F; Ghosh, Sue; Mok, Samuel C; Birrer, Michael J; Samimi, Goli

    2015-12-29

    Ovarian cancer is the most common cause of death among women with gynecologic cancer. We examined molecular profiles of fibroblasts from normal ovary and high-grade serous ovarian tumors to identify novel therapeutic targets involved in tumor progression. We identified 2,300 genes that are significantly differentially expressed in tumor-associated fibroblasts. Fibroblast expression of one of these genes, connective tissue growth factor (CTGF), was confirmed by immunohistochemistry. CTGF protein expression in ovarian tumor fibroblasts significantly correlated with gene expression levels. CTGF is a secreted component of the tumor microenvironment and is being pursued as a therapeutic target in pancreatic cancer. We examined its effect in in vitro and ex vivo ovarian cancer models, and examined associations between CTGF expression and clinico-pathologic characteristics in patients. CTGF promotes migration and peritoneal adhesion of ovarian cancer cells. These effects are abrogated by FG-3019, a human monoclonal antibody against CTGF, currently under clinical investigation as a therapeutic agent. Immunohistochemical analyses of high-grade serous ovarian tumors reveal that the highest level of tumor stromal CTGF expression was correlated with the poorest prognosis. Our findings identify CTGF as a promoter of peritoneal adhesion, likely to mediate metastasis, and a potential therapeutic target in high-grade serous ovarian cancer. These results warrant further studies into the therapeutic efficacy of FG-3019 in high-grade serous ovarian cancer.

  5. Improved system for identifying biological tissue temperature using electrical impedance tomography

    Directory of Open Access Journals (Sweden)

    Korolyuk Evgeniy

    2018-01-01

    Full Text Available This paper proposes a cheap and compact medical system that determines the temperature of an object using broadband impedance tomography. This system can be used in medicine to visualize ice structure in tissue during cryosurgical operations, as well as for fault diagnosis and location in studied industrial objects. These effects are achieved by measuring electrical impedance between electrode pairs in the measuring chamber. The assembled prototype is compact, consumes little power, and allows to non-invasively determine the impedance of a target object in real time. The research included experimental studies to determine the dependence of the impedance spectrum of saline water and muscle tissue on temperature in broad band spectrum, which allowed to obtain the dependence of total electrical impedance of target objects on temperature.

  6. DMPD: Adipose tissue as an immunological organ: Toll-like receptors, C1q/TNFs andCTRPs. [Dynamic Macrophage Pathway CSML Database

    Lifescience Database Archive (English)

    Full Text Available 17681884 Adipose tissue as an immunological organ: Toll-like receptors, C1q/TNFs an...ng) (.svg) (.html) (.csml) Show Adipose tissue as an immunological organ: Toll-like receptors, C1q/TNFs andC...TRPs. PubmedID 17681884 Title Adipose tissue as an immunological organ: Toll-like

  7. Polyamine/salt-assembled microspheres coated with hyaluronic acid for targeting and pH sensing.

    Science.gov (United States)

    Zhang, Pan; Yang, Hui; Wang, Guojun; Tong, Weijun; Gao, Changyou

    2016-06-01

    The poly(allylamine hydrochloride)/trisodium citrate aggregates were fabricated and further covalently crosslinked via the coupling reaction of carboxylic sites on trisodium citrate with the amine groups on polyamine, onto which poly-L-lysine and hyaluronic acid were sequentially assembled, forming stable microspheres. The pH sensitive dye and pH insensitive dye were further labeled to enable the microspheres with pH sensing property. Moreover, these microspheres could be specifically targeted to HeLa tumor cells, since hyaluronic acid can specifically recognize and bind to CD44, a receptor overexpressed on many tumor cells. Quantitative pH measurement by confocal laser scanning microscopy demonstrated that the microspheres were internalized into HeLa cells, and accumulated in acidic compartments. By contrast, only a few microspheres were adhered on the NIH 3T3 cells surface. The microspheres with combined pH sensing property and targeting ability can enhance the insight understanding of the targeted drug vehicles trafficking after cellular internalization. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Bola-amphiphile self-assembly

    DEFF Research Database (Denmark)

    Svaneborg, Carsten

    2012-01-01

    Bola-amphiphiles are rod-like molecules where both ends of the molecule likes contact with water, while the central part of the molecule dislikes contact with water. What do such molecules do when they are dissolved in water? They self-assemble into micelles. This is a Dissipartive particle...... dynamics simulation of this self-assembly behaviour....

  9. Self-assembled 3D flower-like Ni2+-Fe3+ layered double hydroxides and their calcined products

    International Nuclear Information System (INIS)

    Xiao Ting; Tang Yiwen; Jia Zhiyong; Li Dawei; Hu Xiaoyan; Li Bihui; Luo Lijuan

    2009-01-01

    This paper describes a facile solvothermal method to synthesize self-assembled three-dimensional (3D) Ni 2+ -Fe 3+ layered double hydroxides (LDHs). Flower-like Ni 2+ -Fe 3+ LDHs constructed of thin nanopetals were obtained using ethylene glycol (EG) as a chelating reagent and urea as a hydrolysis agent. The reaction mechanism and self-assembly process are discussed. After calcinating the as-prepared LDHs at 450 0 C in nitrogen gas, porous NiO/NiFe 2 O 4 nanosheets were obtained. This work resulted in the development of a simple, cheap, and effective route for the fabrication of large area Ni 2+ -Fe 3+ LDHs as well as porous NiO/NiFe 2 O 4 nanosheets.

  10. Tuning Gas Adsorption Properties of Zeolite-like Supramolecular Assemblies with gis Topology via Functionalization of Isoreticular Metal–Organic Squares

    KAUST Repository

    Wang, Shuang; Belmabkhout, Youssef; Cairns, Amy; Li, Guanghua; Huo, Qisheng; Liu, Yunling; Eddaoudi, Mohamed

    2017-01-01

    A strategy based on metal-ligand directed assembly of metal-organic squares (MOSs), built-up from four-membered ring (4MR) secondary building units (SBUs), has been employed for the design and construction of isoreticular zeolite-like supramolecular

  11. Computed isotopic inventory and dose assessment for SRS fuel and target assemblies

    International Nuclear Information System (INIS)

    Chandler, M.C.; Ketusky, E.T.; Thoman, D.C.

    1995-01-01

    Past studies have identified and evaluated important radionuclide contributors to dose from reprocessed spent fuel sent to waste for Mark 16B and 22 fuel assemblies and for Mark 31 A and 31B target assemblies. Fission-product distributions after a 5- and 15-year decay time were calculated for a ''representative'' set of irradiation conditions (i.e., reactor power, irradiation time, and exposure) for each type of assembly. The numerical calculations were performed using the SHIELD/GLASS system of codes. The sludge and supernate source terms for dose were studied separately with the significant radionuclide contributors for each identified and evaluated. Dose analysis considered both inhalation and ingestion pathways: The inhalation pathway was analyzed for both evaporative and volatile releases. Analysis of evaporative releases utilized release fractions for the individual radionuclides as defined in the ICRP-30 by DOE guidance. A release fraction of unity was assumed for each radionuclide under volatile-type releases, which would encompass internally initiated events (e.g., fires, explosions), process-initiated events, and externally initiated events. Radionuclides which contributed at least 1% to the overall dose were designated as significant contributors. The present analysis extends and complements the past analyses through considering a broader spectrum of fuel types and a wider range of irradiation conditions. The results provide for a more thorough understanding of the influences of fuel composition and irradiation parameters on fission product distributions (at 2 years or more). Additionally, the present work allows for a more comprehensive evaluation of radionuclide contributions to dose and an estimation of the variability in the radionuclide composition of the dose source term that results from the spent fuel sent to waste encompassing a broad spectrum of fuel compositions and irradiation conditions

  12. Interface-Targeting Strategy Enables Two-Photon Fluorescent Lipid Droplet Probes for High-Fidelity Imaging of Turbid Tissues and Detecting Fatty Liver.

    Science.gov (United States)

    Guo, Lifang; Tian, Minggang; Feng, Ruiqing; Zhang, Ge; Zhang, Ruoyao; Li, Xuechen; Liu, Zhiqiang; He, Xiuquan; Sun, Jing Zhi; Yu, Xiaoqiang

    2018-04-04

    Lipid droplets (LDs) with unique interfacial architecture not only play crucial roles in protecting a cell from lipotoxicity and lipoapoptosis but also closely relate with many diseases such as fatty liver and diabetes. Thus, as one of the important applied biomaterials, fluorescent probes with ultrahigh selectivity for in situ and high-fidelity imaging of LDs in living cells and tissues are critical to elucidate relevant physiological and pathological events as well as detect related diseases. However, available probes only utilizing LDs' waterless neutral cores but ignoring the unique phospholipid monolayer interfaces exhibit low selectivity. They cannot differentiate neutral cores of LDs from intracellular other lipophilic microenvironments, which results in extensively cloud-like background noise and severely limited their bioapplications. Herein, to design LD probes with ultrahigh selectivity, the exceptional interfacial architecture of LDs is considered adequately and thus an interface-targeting strategy is proposed for the first time. According to the novel strategy, we have developed two amphipathic fluorescent probes (N-Cy and N-Py) by introducing different cations into a lipophilic fluorophore (nitrobenzoxadiazole (NBD)). Consequently, their cationic moiety precisely locates the interfaces through electrostatic interaction and simultaneously NBD entirely embeds into the waterless core via hydrophobic interaction. Thus, high-fidelity and background-free fluorescence imaging of LDs are expectably realized in living cells in situ. Moreover, LDs in turbid tissues like skeletal muscle slices have been clearly imaged (up to 82 μm depth) by a two-photon microscope. Importantly, using N-Cy, we not only intuitively monitored the variations of LDs in number, size, and morphology but also clearly revealed their abnormity in hepatic tissues resulting from fatty liver. Therefore, these unique probes provide excellent imaging tools for elucidating LD

  13. Mitochondria mediate septin cage assembly to promote autophagy of Shigella.

    Science.gov (United States)

    Sirianni, Andrea; Krokowski, Sina; Lobato-Márquez, Damián; Buranyi, Stephen; Pfanzelter, Julia; Galea, Dieter; Willis, Alexandra; Culley, Siân; Henriques, Ricardo; Larrouy-Maumus, Gerald; Hollinshead, Michael; Sancho-Shimizu, Vanessa; Way, Michael; Mostowy, Serge

    2016-07-01

    Septins, cytoskeletal proteins with well-characterised roles in cytokinesis, form cage-like structures around cytosolic Shigella flexneri and promote their targeting to autophagosomes. However, the processes underlying septin cage assembly, and whether they influence S. flexneri proliferation, remain to be established. Using single-cell analysis, we show that the septin cages inhibit S. flexneri proliferation. To study mechanisms of septin cage assembly, we used proteomics and found mitochondrial proteins associate with septins in S. flexneri-infected cells. Strikingly, mitochondria associated with S. flexneri promote septin assembly into cages that entrap bacteria for autophagy. We demonstrate that the cytosolic GTPase dynamin-related protein 1 (Drp1) interacts with septins to enhance mitochondrial fission. To avoid autophagy, actin-polymerising Shigella fragment mitochondria to escape from septin caging. Our results demonstrate a role for mitochondria in anti-Shigella autophagy and uncover a fundamental link between septin assembly and mitochondria. © 2016 The Authors. Published under the terms of the CC BY 4.0 license.

  14. The fabrication and photocatalytic performances of flower-like Ag nanoparticles/ZnO nanosheets-assembled microspheres

    International Nuclear Information System (INIS)

    Deng, Quan; Tang, Haibin; Liu, Gang; Song, Xiaoping; Xu, Guoping; Li, Qian; Ng, Dickon H.L.; Wang, Guozhong

    2015-01-01

    Graphical abstract: - Highlights: • ZnO nanosheets-assembled microspheres (ZnOs) were prepared. • Ag nanoparticles (Ag-NPs) were decorated onto the whole surface of the ZnOs. • The Ag-NPs/ZnOs composite showed enhanced photocatalytic performance to MB and MO. • Cyclic voltammetry and impedance spectra revealed enhanced charge transportation. - Abstract: A new micro/nanostructure photocatalyst, Ag nanoparticles decorated ZnO nanosheets-assembled microspheres (Ag-NPs/ZnOs), was synthesised by a two-step method. The flower-like micron-sized ZnO spheres assembled with ∼25 nm thick ZnO nanosheets were initially fabricated via a facile solvothermal method. Then, highly dispersed Ag nanoparticles (Ag-NPs) with dimension ranging from 15 to 50 nm were anchored onto the surface of the each ZnO nanosheet by the Sn(II) ion activation method. The as-prepared Ag-NPs/ZnOs demonstrated enhanced photocatalytic performance in eliminating methylene blue and methyl orange aqueous solutions under UV irradiation, showing twice faster reaction rate than the bare ZnOs. The enhanced photocatalytic activity was due to the suppression of electron/hole pair recombination and the acceleration of surface charge transfer induced by the highly dispersive Ag-NPs, which was further demonstrated by the cyclic voltammetry and impedance spectra measurements

  15. Magnetic alginate microfibers as scaffolding elements for the fabrication of microvascular-like structures.

    Science.gov (United States)

    Sun, Tao; Shi, Qing; Huang, Qiang; Wang, Huaping; Xiong, Xiaolu; Hu, Chengzhi; Fukuda, Toshio

    2018-01-15

    Traditional cell-encapsulating scaffolds may elicit adverse host responses and inhomogeneity in cellular distribution. Thus, fabrication techniques for cellular self-assembly with micro-scaffold incorporation have been used recently to generate toroidal cellular modules for the bottom-up construction of vascular-like structures. The micro-scaffolds show advantage in promoting tissue formation. However, owing to the lack of annular cell micro-scaffolds, it remains a challenge to engineer micro-scale toroidal cellular modules (micro-TCMs) to fabricate microvascular-like structures. Here, magnetic alginate microfibers (MAMs) are used as scaffolding elements, where a winding strategy enables them to be formed into micro-rings as annular cell micro-scaffolds. These micro-rings were investigated for NIH/3T3 fibroblast growth as a function of surface chemistry and MAM size. Afterwards, micro-TCMs were successfully fabricated with the formation of NIH/3T3 fibroblasts and extracellular matrix layers on the three-dimensional micro-ring surfaces. Simple non-contact magnetic assembly was used to stack the micro-TCMs along a micro-pillar, after which cell fusion rapidly connected the assembled micro-TCMs into a microvascular-like structure. Endothelial cells or drugs encapsulated in the MAMs could be included in the microvascular-like structures as in vitro cellular models for vascular tissue engineering, or as miniaturization platforms for pharmaceutical drug testing in the future. Magnetic alginate microfibers functioned as scaffolding elements for guiding cell growth in micro-scale toroidal cellular modules (micro-TCMs) and provided a magnetic functionality to the micro-TCMs for non-contact 3D assembly in external magnetic fields. By using the liquid/air interface, the non-contact spatial manipulation of the micro-TCMs in the liquid environment was performed with a cost-effective motorized electromagnetic needle. A new biofabrication paradigm of construct of microvascular-like

  16. GRAbB: Selective Assembly of Genomic Regions, a New Niche for Genomic Research.

    Directory of Open Access Journals (Sweden)

    Balázs Brankovics

    2016-06-01

    Full Text Available GRAbB (Genomic Region Assembly by Baiting is a new program that is dedicated to assemble specific genomic regions from NGS data. This approach is especially useful when dealing with multi copy regions, such as mitochondrial genome and the rDNA repeat region, parts of the genome that are often neglected or poorly assembled, although they contain interesting information from phylogenetic or epidemiologic perspectives, but also single copy regions can be assembled. The program is capable of targeting multiple regions within a single run. Furthermore, GRAbB can be used to extract specific loci from NGS data, based on homology, like sequences that are used for barcoding. To make the assembly specific, a known part of the region, such as the sequence of a PCR amplicon or a homologous sequence from a related species must be specified. By assembling only the region of interest, the assembly process is computationally much less demanding and may lead to assemblies of better quality. In this study the different applications and functionalities of the program are demonstrated such as: exhaustive assembly (rDNA region and mitochondrial genome, extracting homologous regions or genes (IGS, RPB1, RPB2 and TEF1a, as well as extracting multiple regions within a single run. The program is also compared with MITObim, which is meant for the exhaustive assembly of a single target based on a similar query sequence. GRAbB is shown to be more efficient than MITObim in terms of speed, memory and disk usage. The other functionalities (handling multiple targets simultaneously and extracting homologous regions of the new program are not matched by other programs. The program is available with explanatory documentation at https://github.com/b-brankovics/grabb. GRAbB has been tested on Ubuntu (12.04 and 14.04, Fedora (23, CentOS (7.1.1503 and Mac OS X (10.7. Furthermore, GRAbB is available as a docker repository: brankovics/grabb (https://hub.docker.com/r/brankovics/grabb/.

  17. Engineering design and analysis of an ITER-like first mirror test assembly on JET

    DEFF Research Database (Denmark)

    Vizvary, Z.; Bourdel, B.; Garcia-Carrasco, A.

    2017-01-01

    is underway on JET, under contract to ITER, with primary objective to test if, under realistic plasma and wall material conditions and with ITER-like first mirror aperture geometry, deposits do grow on first mirrors. This paper describes the engineering design and analysis of this mirror test assembly......The ITER first mirrors are the components of optical diagnostic systems closest to the plasma. Deposition may build up on the surfaces of the mirror affecting their ability to fulfil their function. However, physics modelling of this layer growth is fraught with uncertainty. A new experiment...

  18. Kinase Gene Expression Profiling of Metastatic Clear Cell Renal Cell Carcinoma Tissue Identifies Potential New Therapeutic Targets.

    Directory of Open Access Journals (Sweden)

    Pooja Ghatalia

    Full Text Available Kinases are therapeutically actionable targets. Kinase inhibitors targeting vascular endothelial growth factor receptors (VEGFR and mammalian target of rapamycin (mTOR improve outcomes in metastatic clear cell renal cell carcinoma (ccRCC, but are not curative. Metastatic tumor tissue has not been comprehensively studied for kinase gene expression. Paired intra-patient kinase gene expression analysis in primary tumor (T, matched normal kidney (N and metastatic tumor tissue (M may assist in identifying drivers of metastasis and prioritizing therapeutic targets. We compared the expression of 519 kinase genes using NanoString in T, N and M in 35 patients to discover genes over-expressed in M compared to T and N tissue. RNA-seq data derived from ccRCC tumors in The Cancer Genome Atlas (TCGA were used to demonstrate differential expression of genes in primary tumor tissue from patients that had metastasis at baseline (n = 79 compared to those that did not develop metastasis for at least 2 years (n = 187. Functional analysis was conducted to identify key signaling pathways by using Ingenuity Pathway Analysis. Of 10 kinase genes overexpressed in metastases compared to primary tumor in the discovery cohort, 9 genes were also differentially expressed in TCGA primary tumors with metastasis at baseline compared to primary tumors without metastasis for at least 2 years: EPHB2, AURKA, GSG2, IKBKE, MELK, CSK, CHEK2, CDC7 and MAP3K8; p<0.001. The top pathways overexpressed in M tissue were pyridoxal 5'-phosphate salvage, salvage pathways of pyrimidine ribonucleotides, NF-kB signaling, NGF signaling and cell cycle control of chromosomal replication. The 9 kinase genes validated to be over-expressed in metastatic ccRCC may represent currently unrecognized but potentially actionable therapeutic targets that warrant functional validation.

  19. Programmed Nanomaterial Assemblies in Large Scales: Applications of Synthetic and Genetically- Engineered Peptides to Bridge Nano-Assemblies and Macro-Assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Matsui, Hiroshi

    2014-09-09

    Work is reported in these areas: Large-scale & reconfigurable 3D structures of precise nanoparticle assemblies in self-assembled collagen peptide grids; Binary QD-Au NP 3D superlattices assembled with collagen-like peptides and energy transfer between QD and Au NP in 3D peptide frameworks; Catalytic peptides discovered by new hydrogel-based combinatorial phage display approach and their enzyme-mimicking 2D assembly; New autonomous motors of metal-organic frameworks (MOFs) powered by reorganization of self-assembled peptides at interfaces; Biomimetic assembly of proteins into microcapsules on oil-in-water droplets with structural reinforcement via biomolecular recognition-based cross-linking of surface peptides; and Biomimetic fabrication of strong freestanding genetically-engineered collagen peptide films reinforced by quantum dot joints. We gained the broad knowledge about biomimetic material assembly from nanoscale to microscale ranges by coassembling peptides and NPs via biomolecular recognition. We discovered: Genetically-engineered collagen-like peptides can be self-assembled with Au NPs to generate 3D superlattices in large volumes (> μm{sup 3}); The assembly of the 3D peptide-Au NP superstructures is dynamic and the interparticle distance changes with assembly time as the reconfiguration of structure is triggered by pH change; QDs/NPs can be assembled with the peptide frameworks to generate 3D superlattices and these QDs/NPs can be electronically coupled for the efficient energy transfer; The controlled assembly of catalytic peptides mimicking the catalytic pocket of enzymes can catalyze chemical reactions with high selectivity; and, For the bacteria-mimicking swimmer fabrication, peptide-MOF superlattices can power translational and propellant motions by the reconfiguration of peptide assembly at the MOF-liquid interface.

  20. Identification and characterization of angiogenesis targets through proteomic profiling of endothelial cells in human cancer tissues.

    Directory of Open Access Journals (Sweden)

    Mehdi Mesri

    Full Text Available Genomic and proteomic analysis of normal and cancer tissues has yielded abundant molecular information for potential biomarker and therapeutic targets. Considering potential advantages in accessibility to pharmacological intervention, identification of targets resident on the vascular endothelium within tumors is particularly attractive. By employing mass spectrometry (MS as a tool to identify proteins that are over-expressed in tumor-associated endothelium relative to normal cells, we aimed to discover targets that could be utilized in tumor angiogenesis cancer therapy. We developed proteomic methods that allowed us to focus our studies on the discovery of cell surface/secreted proteins, as they represent key antibody therapeutic and biomarker opportunities. First, we isolated endothelial cells (ECs from human normal and kidney cancer tissues by FACS using CD146 as a marker. Additionally, dispersed human colon and lung cancer tissues and their corresponding normal tissues were cultured ex-vivo and their endothelial content were preferentially expanded, isolated and passaged. Cell surface proteins were then preferentially captured, digested with trypsin and subjected to MS-based proteomic analysis. Peptides were first quantified, and then the sequences of differentially expressed peptides were resolved by MS analysis. A total of 127 unique non-overlapped (157 total tumor endothelial cell over-expressed proteins identified from directly isolated kidney-associated ECs and those identified from ex-vivo cultured lung and colon tissues including known EC markers such as CD146, CD31, and VWF. The expression analyses of a panel of the identified targets were confirmed by immunohistochemistry (IHC including CD146, B7H3, Thy-1 and ATP1B3. To determine if the proteins identified mediate any functional role, we performed siRNA studies which led to previously unidentified functional dependency for B7H3 and ATP1B3.

  1. Fuel assembly

    International Nuclear Information System (INIS)

    Nakatsuka, Masafumi; Matsuzuka, Ryuji.

    1976-01-01

    Object: To provide a fuel assembly which can decrease pressure loss of coolant to uniform temperature. Structure: A sectional area of a flow passage in the vicinity of an inner peripheral surface of a wrapper tube is limited over the entire length to prevent the temperature of a fuel element in the outermost peripheral portion from being excessively decreased to thereby flatten temperature distribution. To this end, a plurality of pincture-frame-like sheet metals constituting a spacer for supporting a fuel assembly, which has a plurality of fuel elements planted lengthwise and in given spaced relation within the wrapper tube, is disposed in longitudinal grooves and in stacked fashion to form a substantially honeycomb-like space in cross section. The fuel elements are inserted and supported in the space to form a fuel assembly. (Kamimura, M.)

  2. DNA mediated wire-like clusters of self-assembled TiO₂ nanomaterials: supercapacitor and dye sensitized solar cell applications.

    Science.gov (United States)

    Nithiyanantham, U; Ramadoss, Ananthakumar; Ede, Sivasankara Rao; Kundu, Subrata

    2014-07-21

    A new route for the formation of wire-like clusters of TiO₂ nanomaterials self-assembled in DNA scaffold within an hour of reaction time is reported. TiO₂ nanomaterials are synthesized by the reaction of titanium-isopropoxide with ethanol and water in the presence of DNA under continuous stirring and heating at 60 °C. The individual size of the TiO₂ NPs self-assembled in DNA and the diameter of the wires can be tuned by controlling the DNA to Ti-salt molar ratios and other reaction parameters. The eventual diameter of the individual particles varies between 15 ± 5 nm ranges, whereas the length of the nanowires varies in the 2-3 μm range. The synthesized wire-like DNA-TiO₂ nanomaterials are excellent materials for electrochemical supercapacitor and DSSC applications. From the electrochemical supercapacitor experiment, it was found that the TiO₂ nanomaterials showed different specific capacitance (Cs) values for the various nanowires, and the order of Cs values are as follows: wire-like clusters (small size) > wire-like clusters (large size). The highest Cs of 2.69 F g(-1) was observed for TiO₂ having wire-like structure with small sizes. The study of the long term cycling stability of wire-like clusters (small size) electrode were shown to be stable, retaining ca. 80% of the initial specific capacitance, even after 5000 cycles. The potentiality of the DNA-TiO₂ nanomaterials was also tested in photo-voltaic applications and the observed efficiency was found higher in the case of wire-like TiO₂ nanostructures with larger sizes compared to smaller sizes. In future, the described method can be extended for the synthesis of other oxide based materials on DNA scaffold and can be further used in other applications like sensors, Li-ion battery materials or treatment for environmental waste water.

  3. Visceral adipose tissue macrophage-targeted TACE silencing to treat obesity-induced type 2 diabetes.

    Science.gov (United States)

    Yong, Seok-Beom; Song, Yoonsung; Kim, Yong-Hee

    2017-12-01

    Obesity is an increasingly prevalent global health problem. Due to its close relations with metabolic diseases and cancer, new therapeutic approaches for treating obesity and obesity-induced metabolic diseases are required. Visceral white adipose tissue (WAT) has been closely associated with obesity-induced inflammation and adipose tissue macrophages (ATMs) are responsible for obesity-induced inflammation by releasing inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6. TNF-α converting enzyme (TACE) is a transmembrane enzyme that induces the enzymatic cleavage and release of inflammatory cytokines. In this study, we developed a nonviral gene delivery system consisting of an oligopeptide (ATS-9R) that can selectively target visceral ATMs. In here we shows visceral adipose tissue-dominant inflammatory gene over-expressions in obese mouse and our strategy enabled the preferential delivery of therapeutic genes to visceral ATMs and successfully achieved ATM-targeted gene silencing. Finally, ATS-9R-mediated TACE gene silencing in visceral ATMs alleviated visceral fat inflammation and improved type 2 diabetes by reducing whole body inflammation. Copyright © 2017 Elsevier Ltd. All rights reserved.

  4. Maize rayado fino virus capsid proteins assemble into virus-like particles in Escherichia coli.

    Science.gov (United States)

    Hammond, Rosemarie W; Hammond, John

    2010-02-01

    Maize rayado fino virus (MRFV; genus Marafivirus; family Tymoviridae) is an isometric plant virus of 30 nm containing two components: empty shells and complete virus particles (encapsidating the 6.3 kb genomic RNA). Both particles are composed of two serologically related, carboxy co-terminal, coat proteins (CP) of apparent molecular mass 21-22 kDa (CP2) and 24-28 kDa (CP1) in a molar ratio of 3:1, respectively; CP1 contains a 37 amino acid amino terminal extension of CP2. In our study, expression of CP1 or CP2 in Escherichia coli resulted in assembly of each capsid protein into virus-like particles (VLPs), appearing in electron microscopy as stain-permeable (CP2) or stain-impermeable particles (CP1). CP1 VLPs encapsidated bacterial 16S ribosomal RNA, but not CP mRNA, while CP2 VLPs encapsidated neither CP mRNA nor 16S ribosomal RNA. Expression of CP1 and CP2 in E. coli using a co-expression vector resulted in the assembly of VLPs which were stain-impermeable and encapsidated CP mRNA. These results suggest that the N-terminal 37 amino acid residues of CP1, although not required for particle formation, may be involved in the assembly of complete virions and that the presence of both CP1 and CP2 in the particle is required for specific encapsidation of MRFV CP mRNA. (c) 2009 Elsevier B.V. All rights reserved.

  5. The importance of surrounding tissues and window settings for contouring of moving targets

    Energy Technology Data Exchange (ETDEWEB)

    Borm, Kai Joachim [Technische Universitaet Muenchen, Medical School, Munich (Germany); Klinikum rechts der Isar, Technische Universitaet Muenchen, Department of Radiation Oncology, Munich (Germany); Oechsner, Markus; Berndt, Johannes; Combs, Stephanie Elisabeth; Molls, Michael; Duma, Marciana Nona [Klinikum rechts der Isar, Technische Universitaet Muenchen, Department of Radiation Oncology, Munich (Germany)

    2015-09-15

    The aim of the study was to assess the importance of surrounding tissues for the delineation of moving targets in tissue-specific phantoms and to find optimal settings for lung, soft tissue, and liver tumors. Tumor movement was simulated by a water-filled table tennis ball (target volume, TV). Three phantoms were created: corkboards to simulate lung tissue (lung phantom, LunPh), animal fat as fatty soft tissue (fatty tissue phantom, FatPh), and water enhanced with contrast medium as the liver tissue (liver phantom, LivPh). Slow planning three-dimensional compute tomography images (3D-CTs) were acquired with and without phantom movements. One-dimensional tumor movement (1D), three-dimensional tumor movement (3D), as well as a real patient's tumor trajectories were simulated. The TV was contoured using two lung window settings, two soft-tissue window settings, and one liver window setting. The volumes were compared to mathematical calculated values. TVs were underestimated in all phantoms due to movement. The use of soft-tissue windows in the LivPh led to a significantunderestimation of the TV (70.8 % of calculated TV). When common window settings [LunPh + 200 HU/-1,000 HU (upper window/lower window threshold); FatPh: + 240 HU/-120 HU; LivPh: + 175 HU/+ 50 HU] were used, the contoured TVs were: LivPh, 84.0 %; LunPh, 93.2 %, and FatPh, 92.8 %. The lower window threshold had a significant impact on the size of the delineated TV, whereas changes of the upper threshold led only to small differences. The decisive factor for window settings is the lower window threshold (for adequate TV delineation in the lung and fatty-soft tissue it should be lower than density values of surrounding tissue). The use of a liver window should be considered. (orig.) [German] Das Ziel dieser Arbeit war es, den Einfluss des umgebenden Gewebes auf die Konturierung bewegter Objekte zu untersuchen. Um die optimalen CT-Fensterungen fuer Lungen-, Weichteil- und Lebertumoren zu bestimmen

  6. Scaffold-free, label-free and nozzle-free biofabrication technology using magnetic levitational assembly.

    Science.gov (United States)

    Parfenov, Vladislav A; Koudan, Elizaveta V; Bulanova, Elena A; Karalkin, Pavel A; Pereira, Frederico DAS; Norkin, Nikita E; Knyazeva, Alisa D; Gryadunova, Anna A; Petrov, Oleg F; Vasiliev, M M; Myasnikov, Maxim; Chernikov, Valery P; Kasyanov, Vladimir A; Marchenkov, Artem Yu; Brakke, Kenneth A; Khesuani, Yusef D; Demirci, Utkan; Mironov, Vladimir A

    2018-05-31

    Tissue spheroids have been proposed as building blocks in 3D biofabrication. Conventional magnetic force-driven 2D patterning of tissue spheroids requires prior cell labeling by magnetic nanoparticles, meanwhile a label-free approach for 3D magnetic levitational assembly has been introduced. Here we present first-time report on rapid assembly of 3D tissue construct using scaffold-free, nozzle-free and label-free magnetic levitation of tissue spheroids. Chondrospheres of standard size, shape and capable to fusion have been biofabricated from primary sheep chondrocytes using non-adhesive technology. Label-free magnetic levitation was performed using a prototype device equipped with permanent magnets in presence of gadolinium (Gd3+) in culture media, which enables magnetic levitation. Mathematical modeling and computer simulations were used for prediction of magnetic field and kinetics of tissue spheroids assembly into 3D tissue constructs. First, we used polystyrene beads to simulate the assembly of tissue spheroids and to determine the optimal settings for magnetic levitation in presence of Gd3+. Second, we proved the ability of chondrospheres to assemble rapidly into 3D tissue construct in the permanent magnetic field in the presence of Gd3+. Thus, scaffold- and label-free magnetic levitation of tissue spheroids is a promising approach for rapid 3D biofabrication and attractive alternative to label-based magnetic force-driven tissue engineering. . © 2018 IOP Publishing Ltd.

  7. From micelles to fibers: balancing self-assembling and random coiling domains in pH-responsive silk-collagen-like protein-based polymers

    NARCIS (Netherlands)

    Beun, L.H.; Storm, I.M.; Werten, M.W.T.; Wolf, de F.A.; Cohen Stuart, M.A.; Vries, de R.J.

    2014-01-01

    We study the self-assembly of genetically engineered protein-based triblock copolymers consisting of a central pH-responsive silk-like middle block (SHn, where SH is a silk-like octapeptide, (GA)3GH and n is the number of repeats) flanked by hydrophilic random coil outer blocks (C2). Our previous

  8. Value of the radiolabelled GLP-1 receptor antagonist exendin(9-39) for targeting of GLP-1 receptor-expressing pancreatic tissues in mice and humans

    International Nuclear Information System (INIS)

    Waser, Beatrice; Reubi, Jean Claude

    2011-01-01

    Radiolabelled glucagon-like peptide 1 (GLP-1) receptor agonists have recently been shown to successfully image benign insulinomas in patients. Moreover, it was recently reported that antagonist tracers were superior to agonist tracers for somatostatin and gastrin-releasing peptide receptor targeting of tumours. The present preclinical study determines therefore the value of an established GLP-1 receptor antagonist for the in vitro visualization of GLP-1 receptor-expressing tissues in mice and humans. Receptor autoradiography studies with 125 I-GLP-1(7-36)amide agonist or 125 I-Bolton-Hunter-exendin(9-39) antagonist radioligands were performed in mice pancreas and insulinomas as well as in human insulinomas; competition experiments were performed in the presence of increasing concentration of GLP-1(7-36)amide or exendin(9-39). The antagonist 125 I-Bolton-Hunter-exendin(9-39) labels mouse pancreatic β-cells and mouse insulinomas, but it does not label human pancreatic β-cells and insulinomas. High affinity displacement (IC 50 approximately 2 nM) is observed in mouse β-cells and insulinomas with either the exendin(9-39) antagonist or GLP-1(7-36)amide agonist. For comparison, the agonist 125 I-GLP-1(7-36)amide intensively labels mouse pancreatic β-cells, mouse insulinoma and human insulinomas; high affinity displacement is observed for the GLP-1(7-36)amide in all tissues; however, a 5 and 20 times lower affinity is found for exendin(9-39) in the mouse and human tissues, respectively. This study reports a species-dependent behaviour of the GLP-1 receptor antagonist exendin(9-39) that can optimally target GLP-1 receptors in mice but not in human tissue. Due to its overly low binding affinity, this antagonist is an inadequate targeting agent for human GLP-1 receptor-expressing tissues, as opposed to the GLP-1 receptor agonist, GLP-1(7-36)amide. (orig.)

  9. Radiation induced COX-2 expression and mutagenesis at non-targeted lung tissues of gpt delta transgenic mice

    Science.gov (United States)

    Chai, Y; Calaf, G M; Zhou, H; Ghandhi, S A; Elliston, C D; Wen, G; Nohmi, T; Amundson, S A; Hei, T K

    2013-01-01

    Background: Although radiation-induced bystander effects have been confirmed using a variety of endpoints, the mechanism(s) underlying these effects are not well understood, especially for in vivo study. Methods: A 1-cm2 area (1 cm × 1 cm) in the lower abdominal region of gpt delta transgenic mice was irradiated with 5 Gy of 300 keV X-rays, and changes in out-of-field lung and liver were observed. Results: Compared with sham-treated controls, the Spi− mutation frequency increased 2.4-fold in non-targeted lung tissues at 24 h after partial body irradiation (PBIR). Consistent with dramatic Cyclooxygenase 2 (COX-2) induction in the non-targeted bronchial epithelial cells, increasing levels of prostaglandin, together with 8-hydroxydeoxyguanosine, in the out-of-field lung tissues were observed after PBIR. In addition, DNA double-strand breaks and apoptosis were induced in bystander lung tissues after PBIR. Conclusion: The PBIR induces DNA damage and mutagenesis in non-targeted lung tissues, especially in bronchial epithelial cells, and COX-2 has an essential role in bystander mutagenesis. PMID:23321513

  10. Remote handling for an ISIS target change

    International Nuclear Information System (INIS)

    Broome, T.A.; Holding, M.

    1989-01-01

    During 1987 two ISIS targets were changed. This document describes the main features of the remote handling aspects of the work. All the work has to be carried out using remote handling techniques. The radiation level measured on the surface of the reflector when the second target had been removed was about 800 mGy/h demonstrating that hands on operations on any part of the target reflector moderator assembly is not practical. The target changes were the first large scale operations in the Target Station Remote Handling Cell and a great deal was learned about both equipment and working practices. Some general principles emerged which are applicable to other active handling tasks on facilities like ISIS and these are discussed below. 8 figs

  11. Uptake of three [3H]progestins by target tissues in vivo: implications for the design of diagnostic imaging agents

    International Nuclear Information System (INIS)

    Carlson, K.E.; Brandes, S.J.; Pomper, M.G.; Katzenellenbogen, J.A.

    1988-01-01

    We have investigated the tissue distribution of radioactivity for 0.5-4 h following the i.v. injection of three tritium-labeled progestins in estrogen-primed, immature rats. Whereas [ 3 H]progesterone shows minimal uterine uptake ( 3 H]R 5020 (promegestrone) and [ 3 H]ORG 2058 show highly selective uptake that reaches 4-5% ID/g by 1-3 h. The uterus to non-target tissue activity ratio at 2-4 h is approximately 12-20 for R 5020 and ORG 2058, but less than 2 for progesterone; the uterus to blood activity ratio for R 5020 is also high (approximately 15), but is lower for ORG 2058, possibly due to the accumulation of radiolabeled metabolites in the blood. The uterine uptake is selectively blocked by simultaneous injection of a large dose of unlabeled steroid, indicating that the uptake is mediated by a high affinity, low capacity binding system, presumably the progesterone receptor. Pronounced uptake is also observed by the liver and into fat, but is not receptor-mediated. The highly selective target tissue uptake by the two synthetic steroids, but not by progesterone, indicates that one must have ligands with sufficiently high affinity for the target tissue receptor, as well as low affinity for certain non-receptor binding proteins, in order to obtain adequate contrast between target and non-target tissues in dynamic uptake studies. These guidelines will be important in the development of suitable in vivo imaging agents based on the progesterone receptor. (author)

  12. Assembly of collagen into microribbons: effects of pH and electrolytes.

    Science.gov (United States)

    Jiang, Fengzhi; Hörber, Heinrich; Howard, Jonathon; Müller, Daniel J

    2004-12-01

    Collagen represents the major structural protein of the extracellular matrix. Elucidating the mechanism of its assembly is important for understanding many cell biological and medical processes as well as for tissue engineering and biotechnological approaches. In this work, conditions for the self-assembly of collagen type I molecules on a supporting surface were characterized. By applying hydrodynamic flow, collagen assembled into ultrathin ( approximately 3 nm) highly anisotropic ribbon-like structures coating the entire support. We call these novel collagen structures microribbons. High-resolution atomic force microscopy topographs show that subunits of these microribbons are built by fibrillar structures. The smallest units of these fibrillar structures have cross-sections of approximately 3 x 5nm, consistent with current models of collagen microfibril formation. By varying the pH and electrolyte of the buffer solution during the self-assembly process, the microfibril density and contacts formed within this network could be controlled. Under certain electrolyte compositions the microribbons and microfibers display the characteristic D-periodicity of approximately 65 nm observed for much thicker collagen fibrils. In addition to providing insight into the mechanism of collagen assembly, the ultraflat collagen matrices may also offer novel ways to bio-functionalize surfaces.

  13. The chaperonin-60 universal target is a barcode for bacteria that enables de novo assembly of metagenomic sequence data.

    Science.gov (United States)

    Links, Matthew G; Dumonceaux, Tim J; Hemmingsen, Sean M; Hill, Janet E

    2012-01-01

    Barcoding with molecular sequences is widely used to catalogue eukaryotic biodiversity. Studies investigating the community dynamics of microbes have relied heavily on gene-centric metagenomic profiling using two genes (16S rRNA and cpn60) to identify and track Bacteria. While there have been criteria formalized for barcoding of eukaryotes, these criteria have not been used to evaluate gene targets for other domains of life. Using the framework of the International Barcode of Life we evaluated DNA barcodes for Bacteria. Candidates from the 16S rRNA gene and the protein coding cpn60 gene were evaluated. Within complete bacterial genomes in the public domain representing 983 species from 21 phyla, the largest difference between median pairwise inter- and intra-specific distances ("barcode gap") was found from cpn60. Distribution of sequence diversity along the ∼555 bp cpn60 target region was remarkably uniform. The barcode gap of the cpn60 universal target facilitated the faithful de novo assembly of full-length operational taxonomic units from pyrosequencing data from a synthetic microbial community. Analysis supported the recognition of both 16S rRNA and cpn60 as DNA barcodes for Bacteria. The cpn60 universal target was found to have a much larger barcode gap than 16S rRNA suggesting cpn60 as a preferred barcode for Bacteria. A large barcode gap for cpn60 provided a robust target for species-level characterization of data. The assembly of consensus sequences for barcodes was shown to be a reliable method for the identification and tracking of novel microbes in metagenomic studies.

  14. Polo-like kinase phosphorylation determines Caenorhabditis elegans centrosome size and density by biasing SPD-5 toward an assembly-competent conformation

    Directory of Open Access Journals (Sweden)

    Oliver Wueseke

    2016-10-01

    Full Text Available Centrosomes are major microtubule-organizing centers composed of centrioles surrounded by an extensive proteinacious layer called the pericentriolar material (PCM. In Caenorhabditis elegans embryos, the mitotic PCM expands by Polo-like kinase 1 (PLK-1 phosphorylation-accelerated assembly of SPD-5 molecules into supramolecular scaffolds. However, how PLK-1 phosphorylation regulates SPD-5 assembly is not known. We found that a mutant version of SPD-5 that is insensitive to PLK-1 phosphorylation (SPD-54A could localize to PCM but was unable to rescue the reduction in PCM size and density when wild-type SPD-5 levels were decreased. In vitro, purified SPD-54A self-assembled into functional supramolecular scaffolds over long time scales, suggesting that phosphorylation only controls the rate of SPD-5 scaffold assembly. Furthermore, the SPD-5 scaffold, once assembled, remained intact and supported microtubule nucleation in the absence of PLK-1 activity in vivo. We conclude that PLK-1 is required for rapid assembly of the PCM scaffold but not for scaffold maintenance or function. Based on this idea, we developed a theoretical model that adequately predicted PCM growth rates in different mutant conditions in vivo. We propose that PLK-1 phosphorylation-dependent conversion of SPD-5 into an assembly-competent form underlies PCM formation in vivo and that the rate of this conversion determines final PCM size and density.

  15. MicroRNA-876-5p inhibits epithelial-mesenchymal transition and metastasis of hepatocellular carcinoma by targeting BCL6 corepressor like 1.

    Science.gov (United States)

    Xu, Qiuran; Zhu, Qiaojuan; Zhou, Zhenyu; Wang, Yufeng; Liu, Xin; Yin, Guozhi; Tong, Xiangmin; Tu, Kangsheng

    2018-07-01

    Our previous study has reported that BCL6 corepressor like 1 (BCORL1) plays an oncogenic role in hepatocellular carcinoma (HCC) via promoting epithelial-mesenchymal transition (EMT) and tumor metastasis. However, the regulation of BCORL1 mediated by microRNAs (miRNAs) remains poorly known. The analysis of our clinical samples indicated that BCORL1 expression was markedly higher in HCC tissues than that in tumor-adjacent normal tissues. The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) datasets revealed that high BCORL1 expression associated with high tumor grade, advanced tumor stage and poor survival of HCC patients. miR-875-5p expression was down-regulated and negatively correlated with BCORL1 mRNA expression in HCC tissues. Furthermore, miR-876-5p inversely regulated BCORL1 abundance in HCC cells by directly targeting the 3'-untranslated region (3'-UTR) of BCORL1. Ectopic expression of miR-876-5p suppressed cell migration and invasion in both HCCLM3 and MHCC97H cells. In accordance, miR-876-5p knockdown promoted the metastatic behaviors of Hep3B cells. Mechanistically, miR-876-5p suppressed the EMT progression of HCC cells. HCC tissues with high miR-876-5p level showed a higher E-cadherin staining compared to cases with low miR-876-5p level. Moreover, the repression of cell metastasis mediated by miR-876-5p was rescued by BCORL1 restoration in HCCLM3 cells. Notably, low miR-876-5p expression associated with venous infiltration, high tumor grade and advanced tumor stage. HCC patients with low miR-876-5p expression had a significant poorer overall survival and disease-free survival. To conclude, miR-876-5p inhibits EMT progression, migration and invasion of HCC cells by targeting BCORL1. Therefore, miR-876-5p/BCORL1 axis may represent as a novel therapeutic target for HCC treatment. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

  16. Paramecium tetraurelia chromatin assembly factor-1-like protein PtCAF-1 is involved in RNA-mediated control of DNA elimination.

    Science.gov (United States)

    Ignarski, Michael; Singh, Aditi; Swart, Estienne C; Arambasic, Miroslav; Sandoval, Pamela Y; Nowacki, Mariusz

    2014-10-29

    Genome-wide DNA remodelling in the ciliate Paramecium is ensured by RNA-mediated trans-nuclear crosstalk between the germline and the somatic genomes during sexual development. The rearrangements include elimination of transposable elements, minisatellites and tens of thousands non-coding elements called internally eliminated sequences (IESs). The trans-nuclear genome comparison process employs a distinct class of germline small RNAs (scnRNAs) that are compared against the parental somatic genome to select the germline-specific subset of scnRNAs that subsequently target DNA elimination in the progeny genome. Only a handful of proteins involved in this process have been identified so far and the mechanism of DNA targeting is unknown. Here we describe chromatin assembly factor-1-like protein (PtCAF-1), which we show is required for the survival of sexual progeny and localizes first in the parental and later in the newly developing macronucleus. Gene silencing shows that PtCAF-1 is required for the elimination of transposable elements and a subset of IESs. PTCAF-1 depletion also impairs the selection of germline-specific scnRNAs during development. We identify specific histone modifications appearing during Paramecium development which are strongly reduced in PTCAF-1 depleted cells. Our results demonstrate the importance of PtCAF-1 for the epigenetic trans-nuclear cross-talk mechanism. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Natural product-like virtual libraries: recursive atom-based enumeration.

    Science.gov (United States)

    Yu, Melvin J

    2011-03-28

    A new molecular enumerator is described that allows chemically and architecturally diverse sets of natural product-like and drug-like structures to be generated from a core structure as simple as a single carbon atom or as complex as a polycyclic ring system. Integrated with a rudimentary machine-learning algorithm, the enumerator has the ability to assemble biased virtual libraries enriched in compounds predicted to meet target criteria. The ability to dynamically generate relatively small focused libraries in a recursive manner could reduce the computational time and infrastructure necessary to construct and manage extremely large static libraries. Depending on enumeration conditions, natural product-like structures can be produced with a wide range of heterocyclic and alicyclic ring assemblies. Because natural products represent a proven source of validated structures for identifying and designing new drug candidates, mimicking the structural and topological diversity found in nature with a dynamic set of virtual natural product-like compounds may facilitate the creation of new ideas for novel, biologically relevant lead structures in areas of uncharted chemical space.

  18. MicroRNA-214-5p Inhibits the Invasion and Migration of Hepatocellular Carcinoma Cells by Targeting Wiskott-Aldrich Syndrome Like.

    Science.gov (United States)

    Li, Hongdan; Wang, Haoqi; Ren, Zhen

    2018-01-01

    This study aims to explore the effects of microRNA-214-5p (miR-214-5p) on the invasion and migration of Hepatocellular Carcinoma cells (HCC). Hepatocellular Carcinoma tissues and adjacent normal tissues from 44 hepatocellular carcinoma patients were prepared for this study. The HepG2 and BEL-7402 cells were transfected with miR-214-5p mimic and inhibitor. qRT-PCR was performed to detect the expressions of miR-214-5p. Transwell assays were used to detect the invasion and migration assays in HepG2 and BEL-7402 cells. A dual-luciferase reporter assay was conducted to examine the effect of miR-214-5p on Wiskott-Aldrich Syndrome Like (WASL/ N-WASP). Western blot and qRT-PCR were used to measure the expressions of the E-cadherin, N-cadherin and Vimentin proteins. Transwell chamber assays were performed to detect cell invasion and migration. Compared with normal tissues, HCC tissues demonstrated significantly lower expression of miR-214-5p. Overexpression of miR-214-5p significantly inhibited the migration and invasion of HCC cells and inhibition of miR-214-5p promoted the migration and invasion. Additionally, miR-214-5p suppressed the epithelial-mesenchymal transition (EMT). Further study showed WASL was a putative target gene of miR-214-5p. Up-regulating the expression of WASL could reverse the inhibition effect of miR-214-5p on invasion and migration. Our data suggested that miR-214-5p inhibited the invasion and migration of HepG2 and BEL-7402 by targeting WASL in Hepatocellular carcinoma. © 2018 The Author(s). Published by S. Karger AG, Basel.

  19. Quantification of pancreatic cancer proteome and phosphorylome: indicates molecular events likely contributing to cancer and activity of drug targets.

    Directory of Open Access Journals (Sweden)

    David Britton

    Full Text Available LC-MS/MS phospho-proteomics is an essential technology to help unravel the complex molecular events that lead to and propagate cancer. We have developed a global phospho-proteomic workflow to determine activity of signaling pathways and drug targets in pancreatic cancer tissue for clinical application.Peptides resulting from tryptic digestion of proteins extracted from frozen tissue of pancreatic ductal adenocarcinoma and background pancreas (n = 12, were labelled with tandem mass tags (TMT 8-plex, separated by strong cation exchange chromatography, then were analysed by LC-MS/MS directly or first enriched for phosphopeptides using IMAC and TiO2, prior to analysis. In-house, commercial and freeware bioinformatic platforms were used to identify relevant biological events from the complex dataset.Of 2,101 proteins identified, 152 demonstrated significant difference in abundance between tumor and non-tumor tissue. They included proteins that are known to be up-regulated in pancreatic cancer (e.g. Mucin-1, but the majority were new candidate markers such as HIPK1 & MLCK. Of the 6,543 unique phosphopeptides identified (6,284 unique phosphorylation sites, 635 showed significant regulation, particularly those from proteins involved in cell migration (Rho guanine nucleotide exchange factors & MRCKα and formation of focal adhesions. Activator phosphorylation sites on FYN, AKT1, ERK2, HDAC1 and other drug targets were found to be highly modulated (≥2 fold in different cases highlighting their predictive power.Here we provided critical information enabling us to identify the common and unique molecular events likely contributing to cancer in each case. Such information may be used to help predict more bespoke therapy suitable for an individual case.

  20. Quantification of pancreatic cancer proteome and phosphorylome: indicates molecular events likely contributing to cancer and activity of drug targets.

    Science.gov (United States)

    Britton, David; Zen, Yoh; Quaglia, Alberto; Selzer, Stefan; Mitra, Vikram; Löβner, Christopher; Jung, Stephan; Böhm, Gitte; Schmid, Peter; Prefot, Petra; Hoehle, Claudia; Koncarevic, Sasa; Gee, Julia; Nicholson, Robert; Ward, Malcolm; Castellano, Leandro; Stebbing, Justin; Zucht, Hans Dieter; Sarker, Debashis; Heaton, Nigel; Pike, Ian

    2014-01-01

    LC-MS/MS phospho-proteomics is an essential technology to help unravel the complex molecular events that lead to and propagate cancer. We have developed a global phospho-proteomic workflow to determine activity of signaling pathways and drug targets in pancreatic cancer tissue for clinical application. Peptides resulting from tryptic digestion of proteins extracted from frozen tissue of pancreatic ductal adenocarcinoma and background pancreas (n = 12), were labelled with tandem mass tags (TMT 8-plex), separated by strong cation exchange chromatography, then were analysed by LC-MS/MS directly or first enriched for phosphopeptides using IMAC and TiO2, prior to analysis. In-house, commercial and freeware bioinformatic platforms were used to identify relevant biological events from the complex dataset. Of 2,101 proteins identified, 152 demonstrated significant difference in abundance between tumor and non-tumor tissue. They included proteins that are known to be up-regulated in pancreatic cancer (e.g. Mucin-1), but the majority were new candidate markers such as HIPK1 & MLCK. Of the 6,543 unique phosphopeptides identified (6,284 unique phosphorylation sites), 635 showed significant regulation, particularly those from proteins involved in cell migration (Rho guanine nucleotide exchange factors & MRCKα) and formation of focal adhesions. Activator phosphorylation sites on FYN, AKT1, ERK2, HDAC1 and other drug targets were found to be highly modulated (≥2 fold) in different cases highlighting their predictive power. Here we provided critical information enabling us to identify the common and unique molecular events likely contributing to cancer in each case. Such information may be used to help predict more bespoke therapy suitable for an individual case.

  1. Increased levels of dioxin-like substances in adipose tissue in patients with deep infiltrating endometriosis.

    Science.gov (United States)

    Martínez-Zamora, M A; Mattioli, L; Parera, J; Abad, E; Coloma, J L; van Babel, B; Galceran, M T; Balasch, J; Carmona, F

    2015-05-01

    Are the levels of biologically active and the most toxic dioxin-like substances in adipose tissue of patients with deep infiltrating endometriosis (DIE) higher than in a control group without endometriosis? DIE patients have higher levels of dioxins and polychlorinated biphenyls (PCBs) in adipose tissue compared with controls without endometriosis. Some studies have investigated the levels of dioxin-like substances, in serum samples, in patients with endometriosis, with inconsistent results. Case-control study including two groups of patients. The study group (DIE group) consisted of 30 patients undergoing laparoscopic surgery because of DIE. In all patients, an extensive preoperative work-up was performed including clinical exploration, magnetic resonance imaging (MRI) and transvaginal sonography. All patients with DIE underwent a confirmatory histological study for DIE after surgery. The non-endometriosis control group (control group), included the next consecutive patient undergoing laparoscopic surgery in our center due to adnexal benign gynecological disease (ovarian or tubal procedures other than endometriosis) after each DIE patient, and who did not present any type of endometriosis. During the surgical procedure 1-2 g of adipose tissue from the omentum were obtained. Dioxin-like substances were analyzed in adipose tissue in DIE patients and controls without endometriosis. The total toxic equivalence and concentrations of both dioxins and PCBs were significantly higher in patients with DIE in comparison with the control group (P dioxins (2,3,7,8-tetrachlorodibenzo-p-dioxin [2,3,7,8-TCDD] and 1,2,3,7,8-pentachlorodibenzo-p-dioxin [1,2,3,7,8-PeCDD]) (P dioxins and PCBs widely vary in different countries. Furthermore, the strict eligibility criteria used may preclude generalization of the results to other populations and the surgery-based sampling frame may induce a selection bias. Finally, adipose tissue was obtained only from the omentum, and not from other

  2. Self-assembled Nanomaterials for Chemotherapeutic Applications

    Science.gov (United States)

    Shieh, Aileen

    The self-assembly of short designed peptides into functional nanostructures is becoming a growing interest in a wide range of fields from optoelectronic devices to nanobiotechnology. In the medical field, self-assembled peptides have especially attracted attention with several of its attractive features for applications in drug delivery, tissue regeneration, biological engineering as well as cosmetic industry and also the antibiotics field. We here describe the self-assembly of peptide conjugated with organic chromophore to successfully deliver sequence independent micro RNAs into human non-small cell lung cancer cell lines. The nanofiber used as the delivery vehicle is completely non-toxic and biodegradable, and exhibit enhanced permeability effect for targeting malignant tumors. The transfection efficiency with nanofiber as the delivery vehicle is comparable to that of the commercially available RNAiMAX lipofectamine while the toxicity is significantly lower. We also conjugated the peptide sequence with camptothecin (CPT) and observed the self-assembly of nanotubes for chemotherapeutic applications. The peptide scaffold is non-toxic and biodegradable, and drug loading of CPT is high, which minimizes the issue of systemic toxicity caused by extensive burden from the elimination of drug carriers. In addition, the peptide assembly drastically increases the solubility and stability of CPT under physiological conditions in vitro, while active CPT is gradually released from the peptide chain under the slight acidic tumor cell environment. Cytotoxicity results on human colorectal cancer cells and non-small cell lung cancer cell lines display promising anti-cancer properties compared to the parental CPT drug, which cannot be used clinically due to its poor solubility and lack of stability in physiological conditions. Moreover, the peptide sequence conjugated with 5-fluorouracil formed a hydrogel with promising topical chemotherapeutic applications that also display

  3. Thaumatin-like proteins are differentially expressed and localized in phloem tissues of hybrid poplar

    Directory of Open Access Journals (Sweden)

    Dafoe Nicole J

    2010-08-01

    Full Text Available Abstract Background Two thaumatin-like proteins (TLPs were previously identified in phloem exudate of hybrid poplar (Populus trichocarpa × P. deltoides using proteomics methods, and their sieve element localization confirmed by immunofluorescence. In the current study, we analyzed different tissues to further understand TLP expression and localization in poplar, and used immunogold labelling to determine intracellular localization. Results Immunofluorescence using a TLP antiserum confirmed the presence of TLP in punctate, organelle-like structures within sieve elements. On western blots, the antiserum labeled two constitutively expressed proteins with distinct expression patterns. Immunogold labelling suggested that TLPs are associated with starch granules and starch-containing plastids in sieve elements and phloem parenchyma cells. In addition, the antiserum recognized TLPs in the inner cell wall and sieve plate region of sieve elements. Conclusions TLP localization in poplar cells and tissues is complex. TLP1 is expressed predominantly in tissues with a prominent vascular system such as midveins, petioles and stems, whereas the second TLP is primarily expressed in starch-storing plastids found in young leaves and the shoot apex.

  4. Prone versus supine positioning for whole and partial-breast radiotherapy: A comparison of non-target tissue dosimetry

    International Nuclear Information System (INIS)

    Kirby, Anna M.; Evans, Philip M.; Donovan, Ellen M.; Convery, Helen M.; Haviland, Joanna S.; Yarnold, John R.

    2010-01-01

    Purpose: To compare non-target tissue (including left-anterior-descending coronary-artery (LAD)) dosimetry of prone versus supine whole (WBI) and partial-breast irradiation (PBI). Methods and materials: Sixty-five post-lumpectomy breast cancer patients underwent CT-imaging supine and prone. On each dataset, the whole-breast clinical-target-volume (WB-CTV), partial-breast CTV (tumour-bed + 15 mm), ipsilateral-lung and chest-wall were outlined. Heart and LAD were outlined in left-sided cases (n = 30). Tangential-field WBI and PBI plans were generated for each position. Mean LAD, heart, and ipsilateral-lung doses (x mean ), maximum LAD (LAD max ) doses, and the volume of chest-wall receiving 50 Gy (V 50Gy ) were compared. Results: Two-hundred and sixty plans were generated. Prone positioning reduced heart and LAD doses in 19/30 WBI cases (median reduction in LAD mean = 6.2 Gy) and 7/30 PBI cases (median reduction in LAD max = 29.3 Gy) (no difference in 4/30 cases). However, prone positioning increased cardiac doses in 8/30 WBI (median increase in LAD mean = 9.5 Gy) and 19/30 PBI cases (median increase in LAD max = 22.9 Gy) (no difference in 3/30 cases). WB-CTV > 1000cm 3 was associated with improved cardiac dosimetry in the prone position for WBI (p = 0.04) and PBI (p = 0.04). Prone positioning reduced ipsilateral-lung mean in 65/65 WBI and 61/65 PBI cases, and chest-wall V 50Gy in all WBI cases. PBI reduced normal-tissue doses compared to WBI in all cases, regardless of the treatment position. Conclusions: In the context of tangential-field WBI and PBI, prone positioning is likely to benefit left-breast-affected women of larger breast volume, but to be detrimental in left-breast-affected women of smaller breast volume. Right-breast-affected women are likely to benefit from prone positioning regardless of breast volume.

  5. PEGylated Self-Assembled Nano-Bacitracin A: Probing the Antibacterial Mechanism and Real-Time Tracing of Target Delivery in Vivo.

    Science.gov (United States)

    Hong, Wei; Zhao, Yining; Guo, Yuru; Huang, Chengcheng; Qiu, Peng; Zhu, Jia; Chu, Chun; Shi, Hong; Liu, Mingchun

    2018-04-04

    Although nano-self-assemblies of hydrophobic-modified bacitracin A with poly(d,l-lactic- co-glycolic acid) (PLGA) (nano-BA PLGA ) have demonstrated promising antibacterial activities, the application of nano-BA PLGA was severely compromised by low water solubility. In this study, a series of PEGylated PLGA copolymers were selected to conjugate with the N-terminus of bacitracin A to construct PEGylated self-assembled nano-BAs and to further develop nano-self-assemblies of bacitracin A with strong antibacterial potency and high solubility. Compared with nano-BA PLGA , all PEGylated nano-BAs, except nano-BA 5k , exhibited strong antibacterial efficiency against both Gram-positive and Gram-negative bacteria by inducing loss of cytoplasmic membrane potential, membrane permeabilization, and leakage of calcein from artificial cell membranes. Studies elucidating the underlying mechanism of PEGylated nano-BAs against Gram-negative bacteria indicated that the strong hydrophobic and van der Waals interactions between PLGA and lipopolysaccharide (LPS) could bind, neutralize, and disassociate LPS, facilitating cellular uptake of the nanoparticles, which could destabilize the membrane, resulting in cell death. Moreover, PEGylated nano-BAs (nano-BA 12k ) with a longer PLGA block were expected to occupy a higher local density of BA mass on the surface and result in stronger hydrophobic and van der Waals interactions with LPS, which were responsible for the enhanced antibacterial activity against Gram-positive and emerging antibacterial activity against Gram-negative bacteria, respectively. In vivo imaging verified that PEGylated nano-BAs exhibited higher inflammatory tissue distribution and longer circulation time than nano-BA PLGA . Therefore, although PEGylation did not affect antibacterial activity, it is necessary for target delivery and resistance to clearance of the observed PEGylated nano-BAs. In vivo, nano-BA 12k also showed the highest therapeutic index against infection

  6. Uterine progesterone signaling is a target for metformin therapy in PCOS-like rats.

    Science.gov (United States)

    Hu, Min; Zhang, Yuehui; Feng, Jiaxing; Xu, Xue; Zhang, Jiao; Zhao, Wei; Guo, Xiaozhu; Li, Juan; Vestin, Edvin; Cui, Peng; Li, Xin; Wu, Xiao-Ke; Brännström, Mats; Shao, Linus R; Billig, Håkan

    2018-05-01

    Impaired progesterone (P4) signaling is linked to endometrial dysfunction and infertility in women with polycystic ovary syndrome (PCOS). Here, we report for the first time that elevated expression of progesterone receptor (PGR) isoforms A and B parallels increased estrogen receptor (ER) expression in PCOS-like rat uteri. The aberrant PGR-targeted gene expression in PCOS-like rats before and after implantation overlaps with dysregulated expression of Fkbp52 and Ncoa2 , two genes that contribute to the development of uterine P4 resistance. In vivo and in vitro studies of the effects of metformin on the regulation of the uterine P4 signaling pathway under PCOS conditions showed that metformin directly inhibits the expression of PGR and ER along with the regulation of several genes that are targeted dependently or independently of PGR-mediated uterine implantation. Functionally, metformin treatment corrected the abnormal expression of cell-specific PGR and ER and some PGR-target genes in PCOS-like rats with implantation. Additionally, we documented how metformin contributes to the regulation of the PGR-associated MAPK/ERK/p38 signaling pathway in the PCOS-like rat uterus. Our data provide novel insights into how metformin therapy regulates uterine P4 signaling molecules under PCOS conditions. © 2018 Society for Endocrinology.

  7. Canine parvovirus VP2 protein expressed in silkworm pupae self-assembles into virus-like particles with high immunogenicity.

    Directory of Open Access Journals (Sweden)

    Hao Feng

    Full Text Available The VP2 structural protein of parvovirus can produce virus-like particles (VLPs by a self-assembly process in vitro, making VLPs attractive vaccine candidates. In this study, the VP2 protein of canine parvovirus (CPV was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells and pupae. Electron micrographs of VLPs showed that they were very similar in size and morphology when compared to the wild-type parvovirus. The immunogenicity of the VLPs was investigated in mice and dogs. Mice immunized intramuscularly with purified VLPs, in the absence of an adjuvant, elicited CD4(+ and CD8(+ T cell responses and were able to elicit a neutralizing antibody response against CPV, while the oral administration of raw homogenates containing VLPs to the dogs resulted in a systemic immune response and long-lasting immunity. These results demonstrate that the CPV-VLPs stimulate both cellular and humoral immune responses, and so CPV-VLPs may be a promising candidate vaccine for the prevention of CPV-associated disease.

  8. Canine parvovirus VP2 protein expressed in silkworm pupae self-assembles into virus-like particles with high immunogenicity.

    Science.gov (United States)

    Feng, Hao; Hu, Gui-qiu; Wang, Hua-lei; Liang, Meng; Liang, Hongru; Guo, He; Zhao, Pingsen; Yang, Yu-jiao; Zheng, Xue-xing; Zhang, Zhi-fang; Zhao, Yong-kun; Gao, Yu-wei; Yang, Song-tao; Xia, Xian-zhu

    2014-01-01

    The VP2 structural protein of parvovirus can produce virus-like particles (VLPs) by a self-assembly process in vitro, making VLPs attractive vaccine candidates. In this study, the VP2 protein of canine parvovirus (CPV) was expressed using a baculovirus expression system and assembled into parvovirus-like particles in insect cells and pupae. Electron micrographs of VLPs showed that they were very similar in size and morphology when compared to the wild-type parvovirus. The immunogenicity of the VLPs was investigated in mice and dogs. Mice immunized intramuscularly with purified VLPs, in the absence of an adjuvant, elicited CD4(+) and CD8(+) T cell responses and were able to elicit a neutralizing antibody response against CPV, while the oral administration of raw homogenates containing VLPs to the dogs resulted in a systemic immune response and long-lasting immunity. These results demonstrate that the CPV-VLPs stimulate both cellular and humoral immune responses, and so CPV-VLPs may be a promising candidate vaccine for the prevention of CPV-associated disease.

  9. Immunological tumor destruction in a murine melanoma model by targeted LTalpha independent of secondary lymphoid tissue

    DEFF Research Database (Denmark)

    Schrama, D.; Voigt, H.; Eggert, A.O.

    2008-01-01

    BACKGROUND: We previously demonstrated that targeting lymphotoxin alpha (LTalpha) to the tumor evokes its immunological destruction in a syngeneic B16 melanoma model. Since treatment was associated with the induction of peritumoral tertiary lymphoid tissue, we speculated that the induced immune...... response was initiated at the tumor site. METHODS AND RESULTS: In order to directly test this notion, we analyzed the efficacy of tumor targeted LTalpha in LTalpha knock-out (LTalpha(-/-)) mice which lack peripheral lymph nodes. To this end, we demonstrate that tumor-targeted LTalpha mediates the induction...... of specific T-cell responses even in the absence of secondary lymphoid organs. In addition, this effect is accompanied by the initiation of tertiary lymphoid tissue at the tumor site in which B and T lymphocytes are compartmentalized in defined areas and which harbor expanded numbers of tumor specific T cells...

  10. Self-assembly of virus-like particles of porcine circovirus type 2 capsid protein expressed from Escherichia coli

    Directory of Open Access Journals (Sweden)

    Cai Xuepeng

    2010-07-01

    Full Text Available Abstract Background Porcine circovirus 2 (PCV2 is a serious problem to the swine industry and can lead to significant negative impacts on profitability of pork production. Syndrome associated with PCV2 is known as porcine circovirus closely associated with post-weaning multisystemic wasting syndrome (PMWS. The capsid (Cap protein of PCV2 is a major candidate antigen for development of recombinant vaccine and serological diagnostic method. The recombinant Cap protein has the ability to self-assemble into virus-like particles (VLPs in vitro, it is particularly opportunity to develop the PV2 VLPs vaccine in Escherichia coli,(E.coli , because where the cost of the vaccine must be weighed against the value of the vaccinated pig, when it was to extend use the VLPs vaccine of PCV2. Results In this report, a highly soluble Cap-tag protein expressed in E.coli was constructed with a p-SMK expression vector with a fusion tag of small ubiquitin-like modifiers (SUMO. The recombinant Cap was purified using Ni2+ affinity resins, whereas the tag was used to remove the SUMO protease. Simultaneously, the whole native Cap protein was able to self-assemble into VLPs in vitro when viewed under an electron microscope. The Cap-like particles had a size and shape that resembled the authentic Cap. The result could also be applied in the large-scale production of VLPs of PCV2 and could be used as a diagnostic antigen or a potential VLP vaccine against PCV2 infection in pigs. Conclusion we have, for the first time, utilized the SUMO fusion motif to successfully express the entire authentic Cap protein of PCV2 in E. coli. After the cleavage of the fusion motif, the nCap protein has the ability to self-assemble into VLPs, which can be used as as a potential vaccine to protect pigs from PCV2-infection.

  11. Self-assembly of virus-like particles of porcine circovirus type 2 capsid protein expressed from Escherichia coli

    Science.gov (United States)

    2010-01-01

    Background Porcine circovirus 2 (PCV2) is a serious problem to the swine industry and can lead to significant negative impacts on profitability of pork production. Syndrome associated with PCV2 is known as porcine circovirus closely associated with post-weaning multisystemic wasting syndrome (PMWS). The capsid (Cap) protein of PCV2 is a major candidate antigen for development of recombinant vaccine and serological diagnostic method. The recombinant Cap protein has the ability to self-assemble into virus-like particles (VLPs) in vitro, it is particularly opportunity to develop the PV2 VLPs vaccine in Escherichia coli,(E.coli ), because where the cost of the vaccine must be weighed against the value of the vaccinated pig, when it was to extend use the VLPs vaccine of PCV2. Results In this report, a highly soluble Cap-tag protein expressed in E.coli was constructed with a p-SMK expression vector with a fusion tag of small ubiquitin-like modifiers (SUMO). The recombinant Cap was purified using Ni2+ affinity resins, whereas the tag was used to remove the SUMO protease. Simultaneously, the whole native Cap protein was able to self-assemble into VLPs in vitro when viewed under an electron microscope. The Cap-like particles had a size and shape that resembled the authentic Cap. The result could also be applied in the large-scale production of VLPs of PCV2 and could be used as a diagnostic antigen or a potential VLP vaccine against PCV2 infection in pigs. Conclusion we have, for the first time, utilized the SUMO fusion motif to successfully express the entire authentic Cap protein of PCV2 in E. coli. After the cleavage of the fusion motif, the nCap protein has the ability to self-assemble into VLPs, which can be used as as a potential vaccine to protect pigs from PCV2-infection. PMID:20646322

  12. Pyrosequencing revealed shifts of prokaryotic communities between healthy and disease-like tissues of the Red Sea sponge Crella cyathophora

    KAUST Repository

    Gao, Zhao-Ming

    2015-06-11

    Sponge diseases have been widely reported, yet the causal factors and major pathogenic microbes remain elusive. In this study, two individuals of the sponge Crella cyathophora in total that showed similar disease-like characteristics were collected from two different locations along the Red Sea coast separated by more than 30 kilometers. The disease-like parts of the two individuals were both covered by green surfaces, and the body size was much smaller compared with adjacent healthy regions. Here, using high-throughput pyrosequencing technology, we investigated the prokaryotic communities in healthy and disease-like sponge tissues as well as adjacent seawater. Microbes in healthy tissues belonged mainly to the Proteobacteria, Cyanobacteria and Bacteroidetes, and were much more diverse at the phylum level than reported previously. Interestingly, the disease-like tissues from the two sponge individuals underwent shifts of prokaryotic communities and were both enriched with a novel clade affiliated with the phylum Verrucomicrobia, implying its intimate connection with the disease-like Red Sea sponge C. cyathophora. Enrichment of the phylum Verrucomicrobia was also considered to be correlated with the presence of algae assemblages forming the green surface of the disease-like sponge tissues. This finding represents an interesting case of sponge disease and is valuable for further study.

  13. Electrostatic Self-Assembly of Sandwich-Like CoAl-LDH/Polypyrrole/Graphene Nanocomposites with Enhanced Capacitive Performance.

    Science.gov (United States)

    Zhang, Yu; Du, Dongfeng; Li, Xuejin; Sun, Hongman; Li, Li; Bai, Peng; Xing, Wei; Xue, Qingzhong; Yan, Zifeng

    2017-09-20

    A novel sandwich-like composite with ultrathin CoAl-layered double hydroxide (LDH) nanoplates electrostatically assembled on both sides of two-dimensional polypyrrole/graphene (PG) substrate has been successfully fabricated using facile hydrothermal techniques. The PG not only serves as an excellent conductive and structural scaffold to enhance the transmission of electrons and prevent aggregation of CoAl-LDH nanoplates but also contributes to the enhancement of the specific capacitance. Owing to the homogeneous dispersion of CoAl-LDH nanoplates and its intimate interaction with PG substrate, the resulting CoAl-LDH/PG nanocomposite material exhibits excellent capacitive performance, for example, enhanced gravimetric specific capacitance (864 F g -1 at 1 A g -1 ), high rate performance (75% retention at 20 A g -1 ), and excellent cycle life (almost no degradation in supercapacitor performance after 5000 cycles) in aqueous KOH solution. Furthermore, the assembled asymmetric capacitor is able to deliver a superhigh energy density of 46.8 Wh kg -1 at 1.2 kW kg -1 and maintain 90.1% of its initial capacitance after 10 000 cycles. These results indicate a rational assembly strategy toward a high-performance pseudocapacitive electrode material with excellent rate performance, high specific capacitance, and outstanding cycle stability.

  14. Optimizing Transcriptome Assemblies for Eleusine indica Leaf and Seedling by Combining Multiple Assemblies from Three De Novo Assemblers

    Directory of Open Access Journals (Sweden)

    Shu Chen

    2015-03-01

    Full Text Available Due to rapid advances in sequencing technology, increasing amounts of genomic and transcriptomic data are available for plant species, presenting enormous challenges for biocomputing analysis. A crucial first step for a successful transcriptomics-based study is the building of a high-quality assembly. Here, we utilized three different de novo assemblers (Trinity, Velvet, and CLC and the EvidentialGene pipeline tr2aacds to assemble two optimized transcript sets for the notorious weed species, . Two RNA sequencing (RNA-seq datasets from leaf and aboveground seedlings were processed using three assemblers, which resulted in 20 assemblies for each dataset. The contig numbers and N50 values of each assembly were compared to study the effect of read number, k-mer size, and in silico normalization on assembly output. The 20 assemblies were then processed through the tr2aacds pipeline to remove redundant transcripts and to select the transcript set with the best coding potential. Each assembly contributed a considerable proportion to the final transcript combination with the exception of the CLC-k14. Thus each assembler and parameter set did assemble better contigs for certain transcripts. The redundancy, total contig number, N50, fully assembled contig number, and transcripts related to target-site herbicide resistance were evaluated for the EvidentialGene and Trinity assemblies. Comparing the EvidentialGene set with the Trinity assembly revealed improved quality and reduced redundancy in both leaf and seedling EvidentialGene sets. The optimized transcriptome references will be useful for studying herbicide resistance in and the evolutionary process in the three allotetraploid offspring.

  15. Reagent Precoated Targets for Rapid In-Tissue Derivatization of the Anti-Tuberculosis Drug Isoniazid Followed by MALDI Imaging Mass Spectrometry

    Science.gov (United States)

    Manier, M. Lisa; Reyzer, Michelle L.; Goh, Anne; Dartois, Veronique; Via, Laura E.; Barry, Clifton E.; Caprioli, Richard M.

    2011-08-01

    Isoniazid (INH) is an important component of front-line anti-tuberculosis therapy with good serum pharmacokinetics but unknown ability to penetrate tuberculous lesions. However, endogenous background interferences hinder our ability to directly analyze INH in tissues. Chemical derivatization has been successfully used to measure isoniazid directly from tissue samples using matrix-assisted laser desorption/ionization (MALDI) imaging mass spectrometry (IMS). MALDI targets were pretreated with trans-cinnamaldehyde (CA) prior to mounting tissue slices. Isoniazid present in the tissues was efficiently derivatized and the INH-CA product measured by MS/MS. Precoating of MALDI targets allows the tissues to be directly thaw-mounted and derivatized, thus simplifying the preparation. A time-course series of tissues from tuberculosis infected/INH dosed animals were assayed and the MALDI MS/MS response correlates well with the amount of INH determined to be in the tissues by high-performance liquid chromatography (HPLC)-MS/MS.

  16. Integration of Self-Assembled Microvascular Networks with Microfabricated PEG-Based Hydrogels.

    Science.gov (United States)

    Cuchiara, Michael P; Gould, Daniel J; McHale, Melissa K; Dickinson, Mary E; West, Jennifer L

    2012-11-07

    Despite tremendous efforts, tissue engineered constructs are restricted to thin, simple tissues sustained only by diffusion. The most significant barrier in tissue engineering is insufficient vascularization to deliver nutrients and metabolites during development in vitro and to facilitate rapid vascular integration in vivo. Tissue engineered constructs can be greatly improved by developing perfusable microvascular networks in vitro in order to provide transport that mimics native vascular organization and function. Here a microfluidic hydrogel is integrated with a self-assembling pro-vasculogenic co-culture in a strategy to perfuse microvascular networks in vitro. This approach allows for control over microvascular network self-assembly and employs an anastomotic interface for integration of self-assembled micro-vascular networks with fabricated microchannels. As a result, transport within the system shifts from simple diffusion to vessel supported convective transport and extra-vessel diffusion, thus improving overall mass transport properties. This work impacts the development of perfusable prevascularized tissues in vitro and ultimately tissue engineering applications in vivo.

  17. New bioactive motifs and their use in functionalized self-assembling peptides for NSC differentiation and neural tissue engineering

    Science.gov (United States)

    Gelain, F.; Cigognini, D.; Caprini, A.; Silva, D.; Colleoni, B.; Donegá, M.; Antonini, S.; Cohen, B. E.; Vescovi, A.

    2012-04-01

    Developing functionalized biomaterials for enhancing transplanted cell engraftment in vivo and stimulating the regeneration of injured tissues requires a multi-disciplinary approach customized for the tissue to be regenerated. In particular, nervous tissue engineering may take a great advantage from the discovery of novel functional motifs fostering transplanted stem cell engraftment and nervous fiber regeneration. Using phage display technology we have discovered new peptide sequences that bind to murine neural stem cell (NSC)-derived neural precursor cells (NPCs), and promote their viability and differentiation in vitro when linked to LDLK12 self-assembling peptide (SAPeptide). We characterized the newly functionalized LDLK12 SAPeptides via atomic force microscopy, circular dichroism and rheology, obtaining nanostructured hydrogels that support human and murine NSC proliferation and differentiation in vitro. One functionalized SAPeptide (Ac-FAQ), showing the highest stem cell viability and neural differentiation in vitro, was finally tested in acute contusive spinal cord injury in rats, where it fostered nervous tissue regrowth and improved locomotor recovery. Interestingly, animals treated with the non-functionalized LDLK12 had an axon sprouting/regeneration intermediate between Ac-FAQ-treated animals and controls. These results suggest that hydrogels functionalized with phage-derived peptides may constitute promising biomimetic scaffolds for in vitro NSC differentiation, as well as regenerative therapy of the injured nervous system. Moreover, this multi-disciplinary approach can be used to customize SAPeptides for other specific tissue engineering applications.Developing functionalized biomaterials for enhancing transplanted cell engraftment in vivo and stimulating the regeneration of injured tissues requires a multi-disciplinary approach customized for the tissue to be regenerated. In particular, nervous tissue engineering may take a great advantage from the

  18. Are predictions of cancer response to targeted drugs, based on effects in unrelated tissues, the 'Black Swan' events?

    Science.gov (United States)

    Kurbel, Beatrica; Golem, Ante Zvonimir; Kurbel, Sven

    2015-01-01

    Adverse effects of targeted drugs on normal tissues can predict the cancer response. Rash correlates with efficacy of erlotinib, cetuximab and gefitinib and onset of arterial hypertension with response to bevacizumab, sunitinib, axitinib and sorafenib, possible examples of 'Black Swan' events, unexpected scientific observations, as described by Karl Popper in 1935. The proposition is that our patients have individual intrinsic variants of cell growth control, important for tumor response and adverse effects on tumor-unrelated tissue. This means that the lack of predictive side effects in healthy tissue is linked with poor results of tumor therapy when tumor resistance is caused by mechanisms that protect all cells of that patient from the targeted drug effects.

  19. Human Dental Pulp-Derived Cells Produce Bone-Like Tissue and Exhibit Bone Cell-Like Responsiveness to Mechanical Loading

    DEFF Research Database (Denmark)

    Kraft, David Christian Evar; Melsen, Birte; Bindslev, Dorthe Arenholt

    2010-01-01

    and characterize cell lines from human 3rd molar dental pulp tissue to determine whether human dental pulp-derived cells (DPCs) are osteogenic and responsive to mechanical loading by pulsating fluid flow (PFF) in vitro. Methods: Human DPCs used for this study were characterized by measuring proliferation....... We also assessed bone formation by DPCs on hydroxyapatite-tricalcium phosphate granules after subcutaneous implantation in mice. Results: We found that DPCs are intrinsically mechanosensitive and, like osteogenic cells, respond to PFF-induced fluid shear stress. Implantation of DPCs resulted...... remodeling in vivo, and therefore provide a promising new tool for regenerative dentistry, for example mineralized tissue engineering to restore bone defects in relation to periodontitis, periimplantatis and orofacial surgery. Experiments in progress have proven that DPCSs are also useful for assessing...

  20. Three-dimensional assembly of tissue-engineered cartilage constructs results in cartilaginous tissue formation without retainment of zonal characteristics.

    Science.gov (United States)

    Schuurman, W; Harimulyo, E B; Gawlitta, D; Woodfield, T B F; Dhert, W J A; van Weeren, P R; Malda, J

    2016-04-01

    Articular cartilage has limited regenerative capabilities. Chondrocytes from different layers of cartilage have specific properties, and regenerative approaches using zonal chondrocytes may yield better replication of the architecture of native cartilage than when using a single cell population. To obtain high seeding efficiency while still mimicking zonal architecture, cell pellets of expanded deep zone and superficial zone equine chondrocytes were seeded and cultured in two layers on poly(ethylene glycol)-terephthalate-poly(butylene terephthalate) (PEGT-PBT) scaffolds. Scaffolds seeded with cell pellets consisting of a 1:1 mixture of both cell sources served as controls. Parallel to this, pellets of superficial or deep zone chondrocytes, and combinations of the two cell populations, were cultured without the scaffold. Pellet cultures of zonal chondrocytes in scaffolds resulted in a high seeding efficiency and abundant cartilaginous tissue formation, containing collagen type II and glycosaminoglycans (GAGs) in all groups, irrespective of the donor (n = 3), zonal population or stratified scaffold-seeding approach used. However, whereas total GAG production was similar, the constructs retained significantly more GAG compared to pellet cultures, in which a high percentage of the produced GAGs were secreted into the culture medium. Immunohistochemistry for zonal markers did not show any differences between the conditions. We conclude that spatially defined pellet culture in 3D scaffolds is associated with high seeding efficiency and supports cartilaginous tissue formation, but did not result in the maintenance or restoration of the original zonal phenotype. The use of pellet-assembled constructs leads to a better retainment of newly produced GAGs than the use of pellet cultures alone. Copyright © 2013 John Wiley & Sons, Ltd.

  1. Assembly of hydrogel units for 3D microenvironment in a poly(dimethylsiloxane) channel

    Science.gov (United States)

    Cho, Chang Hyun; Kwon, Seyong; Park, Je-Kyun

    2017-12-01

    Construction of three-dimensional (3D) microenvironment become an important issue in recent biological studies due to their biological relevance compared to conventional two-dimensional (2D) microenvironment. Various fabrication techniques have been employed to construct a 3D microenvironment, however, it is difficult to fully satisfy the biological and mechanical properties required for the 3D cell culture system, such as heterogeneous tissue structures generated from the functional differences or diseases. We propose here an assembly method for facile construction of 3D microenvironment in a poly(dimethylsiloxane) (PDMS) channel using hydrogel units. The high-aspect-ratio of hydrogel units was achieved by fabricating these units using a 2D mold. With this approach, 3D heterogeneous hydrogel units were produced and assembled in a PDMS channel by structural hookup. In vivo-like 3D heterogeneous microenvironment in a precisely controllable fluidic system was also demonstrated using a controlled assembly of different types of hydrogel units, which was difficult to obtain from previous methods. By regulating the flow condition, the mechanical stability of the assembled hydrogel units was verified by the flow-induced deformation of hydrogel units. In addition, in vivo-like cell culture environment was demonstrated using an assembly of cell-coated hydrogel units in the fluidic channel. Based on these features, our method expects to provide a beneficial tool for the 3D cell culture module and biomimetic engineering.

  2. Self-assembly of tissue spheroids on polymeric membranes.

    Science.gov (United States)

    Messina, Antonietta; Morelli, Sabrina; Forgacs, Gabor; Barbieri, Giuseppe; Drioli, Enrico; De Bartolo, Loredana

    2017-07-01

    In this study, multicellular tissue spheroids were fabricated on polymeric membranes in order to accelerate the fusion process and tissue formation. To this purpose, tissue spheroids composed of three different cell types, myoblasts, fibroblasts and neural cells, were formed and cultured on agarose and membranes of polycaprolactone (PCL) and chitosan (CHT). Membranes prepared by a phase-inversion technique display different physicochemical, mechanical and transport properties, which can affect the fusion process. The membranes accelerated the fusion process of a pair of spheroids with respect to the inert substrate. In this process, a critical role is played by the membrane properties, especially by their mechanical characteristics and oxygen and carbon dioxide mass transfer. The rate of fusion was quantified and found to be similar for fibroblast, myoblast and neural tissue spheroids on membranes, which completed the fusion within 3 days. These spheroids underwent faster fusion and maturation on PCL membrane than on agarose, the rate of fusion being proportional to the value of oxygen and carbon dioxide permeances and elastic characteristics. Consequently, tissue spheroids on the membranes expressed high biological activity in terms of oxygen uptake, making them more suitable as building blocks in the fabrication of tissues and organs. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.

  3. Self-assembled Multifunctional DNA Nanoflowers for the Circumvention of Multidrug Resistance in Targeted Anticancer Drug Delivery.

    Science.gov (United States)

    Mei, Lei; Zhu, Guizhi; Qiu, Liping; Wu, Cuichen; Chen, Huapei; Liang, Hao; Cansiz, Sena; Lv, Yifan; Zhang, Xiaobing; Tan, Weihong

    2015-11-01

    Cancer chemotherapy has been impeded by side effects and multidrug resistance (MDR) partially caused by drug efflux from cancer cells, which call for targeted drug delivery systems additionally able to circumvent MDR. Here we report multifunctional DNA nanoflowers (NFs) for targeted drug delivery to both chemosensitive and MDR cancer cells and circumvent MDR in both leukemia and breast cancer cell models. NFs are self-assembled via liquid crystallization of DNA generated by Rolling Circle Replication, during which NFs are incorporated with aptamers for specific cancer cell recognition, fluorophores for bioimaging, and Doxorubicin (Dox)-binding DNA for drug delivery. NF sizes are tunable (down to ~200 nm in diameter), and the densely packed drug-binding motifs and porous intrastructures endow NFs with high drug loading capacity (71.4%, wt/wt). The Dox-loaded NFs (NF-Dox) are stable at physiological pH, yet drug release is facilitated in acidic or basic conditions. NFs deliver Dox into target chemosensitive and MDR cancer cells, preventing drug efflux and enhancing drug retention in MDR cells. Consequently, NF-Dox induces potent cytotoxicity in both target chemosensitive cells and MDR cells, but not nontarget cells, thus concurrently circumventing MDR and reducing side effects. Overall, these NFs are promising to circumvent MDR in targeted cancer therapy.

  4. In situ assembly states of (Na+,K+)-pump ATPase in human erythrocytes. Radiation target size analyses

    International Nuclear Information System (INIS)

    Hah, J.; Goldinger, J.M.; Jung, C.Y.

    1985-01-01

    The in situ assembly state of the (Na+,K+)-pump ATPase of human erythrocytes was studied by applying the classical target theory to radiation inactivation data of the ouabain-sensitive sodium efflux and ATP hydrolysis. Erythrocytes and their extensively washed white ghosts were irradiated at -45 to -50 degrees C with an increasing dose of 1.5-MeV electron beam, and after thawing, the Na+-pump flux and/or enzyme activities were assayed. Each activity measured was reduced as a simple exponential function of radiation dose, from which a radiation sensitive mass (target size) was calculated. When intact cells were used, the target sizes for the pump and for the ATPase activities were equal and approximately 620,000 daltons. The target size for the ATPase activity was reduced to approximately 320,000 daltons if the cells were pretreated with digitoxigenin. When ghosts were used, the target size for the ATPase activity was again approximately 320,000 daltons. Our target size measurements together with other information available in literature suggest that (Na+,K+)-pump ATPase may exist in human erythrocytes either as a tetramer of alpha beta or as a dimer of alpha beta in tight association with other protein mass, probably certain glycolytic enzymes, and that this tetrameric or heterocomplex association is dissociable by digitoxigenin treatment or by extensive wash during ghost preparation

  5. mRNA Expression of Ovine Angiopoietin-like Protein 4 Gene in Adipose Tissues

    Directory of Open Access Journals (Sweden)

    Jing Zhang

    2016-05-01

    Full Text Available Angiopoietin-like protein 4 (ANGPTL4 is involved in a variety of functions, including lipoprotein metabolism and angiogenesis. To reveal the role of ANGPTL4 in fat metabolism of sheep, ovine ANGPTL4 mRNA expression was analyzed in seven adipose tissues from two breeds with distinct tail types. Forty-eight animals with the gender ratio of 1:1 for both Guangling Large Tailed (GLT and Small Tailed Han (STH sheep were slaughtered at 2, 4, 6, 8, 10, and 12 months of age, respectively. Adipose tissues were collected from greater and lesser omental, subcutaneous, retroperitoneal, perirenal, mesenteric, and tail fats. Ontogenetic mRNA expression of ANGPTL4 in these adipose tissues from GTL and STH was studied by quantitative real time polymerase chain reaction. The results showed that ANGPTL4 mRNA expressed in all adipose tissues studied with the highest in subcutaneous and the lowest in mesenteric fat depots. Months of age, tissue and breed are the main factors that significantly influence the mRNA expression. These results provide new insights into ovine ANGPTL4 gene expression and clues for its function mechanism.

  6. Charge neutralization as the major factor for the assembly of nucleocapsid-like particles from C-terminal truncated hepatitis C virus core protein

    OpenAIRE

    Theo Luiz Ferraz de Souza; Sheila Maria Barbosa de Lima; Vanessa L. de Azevedo Braga; David S. Peabody; Davis Fernandes Ferreira; M. Lucia Bianconi; Andre Marco de Oliveira Gomes; Jerson Lima Silva; Andréa Cheble de Oliveira

    2016-01-01

    Background Hepatitis C virus (HCV) core protein, in addition to its structural role to form the nucleocapsid assembly, plays a critical role in HCV pathogenesis by interfering in several cellular processes, including microRNA and mRNA homeostasis. The C-terminal truncated HCV core protein (C124) is intrinsically unstructured in solution and is able to interact with unspecific nucleic acids, in the micromolar range, and to assemble into nucleocapsid-like particles (NLPs) in vitro. The specific...

  7. Disulfide-induced self-assembled targets : A novel strategy for the label free colorimetric detection of DNAs/RNAs via unmodified gold nanoparticles

    NARCIS (Netherlands)

    Shokri, Ehsan; Hosseini, Morteza; Davari, Mehdi D.; Ganjali, Mohammad R.; Peppelenbosch, Maikel P.; Rezaee, Farhad

    2017-01-01

    A modified non-cross-linking gold-nanoparticles (Au-NPs) aggregation strategy has been developed for the label free colorimetric detection of DNAs/RNAs based on self-assembling target species in the presence of thiolated probes. Two complementary thiol-modified probes, each of which specifically

  8. Disulfide-induced self-assembled targets: A novel strategy for the label free colorimetric detection of DNAs/RNAs via unmodified gold nanoparticles

    NARCIS (Netherlands)

    Shokri, E. (Ehsan); M. Hosseini (Morteza); Davari, M.D. (Mehdi D.); Ganjali, M.R. (Mohammad R.); M.P. Peppelenbosch (Maikel); F. Rezaee (Farhad)

    2017-01-01

    textabstractA modified non-cross-linking gold-nanoparticles (Au-NPs) aggregation strategy has been developed for the label free colorimetric detection of DNAs/RNAs based on self-assembling target species in the presence of thiolated probes. Two complementary thiol- modified probes, each of which

  9. Plasma and adipose tissue level of angiopoietin-like 7 (ANGPTL7) are increased in obesity and reduced after physical exercise.

    Science.gov (United States)

    Abu-Farha, Mohamed; Cherian, Preethi; Al-Khairi, Irina; Madhu, Dhanya; Tiss, Ali; Warsam, Samia; Alhubail, Asma; Sriraman, Devarajan; Al-Refaei, Faisal; Abubaker, Jehad

    2017-01-01

    ANGPTL7 is a member of the Angiopoietin-like (ANGPTL) protein family that is composed of eight proteins (1-8). Increasing evidence is associating ANGPTL proteins to obesity and insulin resistance. The biological role of ANGPTL7 is yet to be understood except for a recently proposed role in the pathophysiology of glaucoma. This study was designed to shed light on the function of ANGPTL7 in obesity and its modulation by physical exercise as well as its potential association with lipid profile. A total of 144 subjects were enrolled in this study and finished three months of physical exercise. The participants were classified based on their BMI, 82 subjects were non-obese and 62 obese. ANGPTL7 levels in plasma and adipose tissue were measured by ELISA, RT-PCR and immunohistochemistry. In this study, we showed that ANGPTL7 level was increased in the plasma of obese subjects (1249.05± 130.39 pg/mL) as compared to non-obese (930.34 ± 87.27 pg/mL) (p-Value = 0.032). ANGPTL7 Gene and protein expression levels in adipose tissue also showed over two fold increase. Physical exercise reduced circulating level of ANGPTL7 in the obese subjects to 740.98± 127.18 pg/mL, (p-Value = 0.007). ANGPTL7 expression in adipose tissue was also reduced after exercise. Finally, ANGPTL7 circulating level showed significant association with TG level in the obese subjects (R2 = 0.183, p-Value = 0.03). In conclusion, our data shows for the first time that obesity increases the level of ANGPTL7 in both plasma and adipose tissue. Increased expression of ANGPTL7 might play a minor role in the regulation of TG level in obese subjects either directly or through interaction with other ANGPTL protein members. Physical exercise reduced the level of ANGPTL7 highlighting the potential for targeting this protein as a therapeutic target for regulating dyslipidemia.

  10. Charge neutralization as the major factor for the assembly of nucleocapsid-like particles from C-terminal truncated hepatitis C virus core protein.

    Science.gov (United States)

    de Souza, Theo Luiz Ferraz; de Lima, Sheila Maria Barbosa; Braga, Vanessa L de Azevedo; Peabody, David S; Ferreira, Davis Fernandes; Bianconi, M Lucia; Gomes, Andre Marco de Oliveira; Silva, Jerson Lima; de Oliveira, Andréa Cheble

    2016-01-01

    Hepatitis C virus (HCV) core protein, in addition to its structural role to form the nucleocapsid assembly, plays a critical role in HCV pathogenesis by interfering in several cellular processes, including microRNA and mRNA homeostasis. The C-terminal truncated HCV core protein (C124) is intrinsically unstructured in solution and is able to interact with unspecific nucleic acids, in the micromolar range, and to assemble into nucleocapsid-like particles (NLPs) in vitro . The specificity and propensity of C124 to the assembly and its implications on HCV pathogenesis are not well understood. Spectroscopic techniques, transmission electron microscopy and calorimetry were used to better understand the propensity of C124 to fold or to multimerize into NLPs when subjected to different conditions or in the presence of unspecific nucleic acids of equivalent size to cellular microRNAs. The structural analysis indicated that C124 has low propensity to self-folding. On the other hand, for the first time, we show that C124, in the absence of nucleic acids, multimerizes into empty NLPs when subjected to a pH close to its isoelectric point (pH ≈ 12), indicating that assembly is mainly driven by charge neutralization. Isothermal calorimetry data showed that the assembly of NLPs promoted by nucleic acids is enthalpy driven. Additionally, data obtained from fluorescence correlation spectroscopy show that C124, in nanomolar range, was able to interact and to sequester a large number of short unspecific nucleic acids into NLPs. Together, our data showed that the charge neutralization is the major factor for the nucleocapsid-like particles assembly from C-terminal truncated HCV core protein. This finding suggests that HCV core protein may physically interact with unspecific cellular polyanions, which may correspond to microRNAs and mRNAs in a host cell infected by HCV, triggering their confinement into infectious particles.

  11. Layer-by-layer assembly of type I collagen and chondroitin sulfate on aminolyzed PU for potential cartilage tissue engineering application

    Science.gov (United States)

    He, Xianyun; Wang, Yingjun; Wu, Gang

    2012-10-01

    In this paper, a two-step method was used to synthesize a biodegradable polyurethane (PU) composed of L-lysine ethyl ester diisocyanate (LDI), poly(ɛ-caprolactone) diols (PCL-diol) and 1,4:3,6-dianhydro-D-sorbitol (isosorbide). Amino groups were introduced onto the surface of the PU membrane by an amination reacting with 1,3-propanediamine to produce polycationic substratum. And then, type I collagen (Col) and chondroitin sulfate (CS) were deposited alternately on the polycationic substratum through layer-by-layer (LBL) assembly technology. The FTIR and 1H NMR results showed that the polyurethane was successfully synthesized. Rhodamine B isothiocyanate (RBITC) fluorescence spectrum indicated that amino groups were successfully introduced onto the PU surface. The results of quartz-crystal microbalance (QCM) and RBITC-Col fluorescence spectroscopy monitoring the LBL assemble process presented that the Col/CS deposited alternately on the PU surface. X-ray photoelectron spectroscopy (XPS) results displayed that the CS deposited on the PU surface as well. The surface of the assembled PU became even smoother observed from the surface morphology by atomic force microscopy (AFM) imaging. The hydrophilicity of the PU membrane was greatly enhanced though the modification of LBL assembly. The PU modified with the adsorption of Col/CS may be a potential application for cartilage tissue engineering due to its created mimicking chondrogenic environment.

  12. CmRBP50 protein phosphorylation is essential for assembly of a stable phloem-mobile high-affinity ribonucleoprotein complex.

    Science.gov (United States)

    Li, Pingfang; Ham, Byung-Kook; Lucas, William J

    2011-07-01

    RNA-binding proteins (RBPs) form ribonucleoprotein (RNP) complexes that play crucial roles in RNA processing for gene regulation. The angiosperm sieve tube system contains a unique population of transcripts, some of which function as long-distance signaling agents involved in regulating organ development. These phloem-mobile mRNAs are translocated as RNP complexes. One such complex is based on a phloem RBP named Cucurbita maxima RNA-binding protein 50 (CmRBP50), a member of the polypyrimidine track binding protein family. The core of this RNP complex contains six additional phloem proteins. Here, requirements for assembly of this CmRBP50 RNP complex are reported. Phosphorylation sites on CmRBP50 were mapped, and then coimmunoprecipitation and protein overlay studies established that the phosphoserine residues, located at the C terminus of CmRBP50, are critical for RNP complex assembly. In vitro pull-down experiments revealed that three phloem proteins, C. maxima phloem protein 16, C. maxima GTP-binding protein, and C. maxima phosphoinositide-specific phospholipase-like protein, bind directly with CmRBP50. This interaction required CmRBP50 phosphorylation. Gel mobility-shift assays demonstrated that assembly of the CmRBP50-based protein complex results in a system having enhanced binding affinity for phloem-mobile mRNAs carrying polypyrimidine track binding motifs. This property would be essential for effective long-distance translocation of bound mRNA to the target tissues.

  13. Somatomedin-C/insulin-like growth factor-I and Insulin-like growth factor-II mRNAs in rate fetal and adult tissues

    International Nuclear Information System (INIS)

    Lund, P.K.; Moats-Staats, B.M.; Hynes, M.A.; Simmons, J.G.; Jansen, M.; D'ercole, A.J.; Van Wyk, J.J.

    1986-01-01

    Somatomedin-C or insulin-like growth factor I (Sm-C/IGF-I) and insulin-like growth factor II (IGF-II) have been implicated in the regulation of fetal growth and development. In the present study 32 P-labeled complementary DNA probes encoding human and mouse Sm-C/IGF-I and human IGF-II were used in Northern blot hybridizations to analyze rat Sm-C/IGF-I and IGF-II mRNAs in poly(A + ) RNAs from intestine, liver, lung, and brain of adult rats and fetal rats between day 14 and 17 of gestation. In fetal rats, all four tissues contained a major mRNA of 1.7 kilobase (kb) that hybridized with the human Sm-C/IGF-I cDNA and mRNAs of 7.5, 4.7, 1.7, and 1.2 kb that hybridized with the mouse Sm-C/IGF-I cDNA. Adult rat intestine, liver, and lung also contained these mRNAs but Sm-C/IGF-I mRNAs were not detected in adult rat brain. These findings provide direct support for prior observations that multiple tissues in the fetus synthesize immunoreactive Sm-C/IGF-I and imply a role for Sm-C/IGF-I in fetal development as well as postnatally. Multiple IGF-II mRNAs of estimated sizes 4.7, 3.9, 2.2, 1.75, and 1.2 kb were observed in fetal rat intestine, liver, lung, and brain. The 4.7- and 3.9-kb mRNAs were the major hybridizing IGF-II mRNAs in all fetal tissues. Higher abundance of IGF-II mRNAs in rat fetal tissues compared with adult tissues supports prior hypotheses, based on serum IGF-II concentrations, that IGF-II is predominantly a fetal somatomedin. IGF-II mRNAs are present, however, in some poly(A + ) RNAs from adult rat tissues. The brain was the only tissue in the adult rat where the 4.7- and 3.9-kb IGF-II mRNAs were consistently detected. These findings suggest that a role for IGF-II in the adult rat, particularly in the central nervous system, cannot be excluded

  14. Development and testing of a deuterium gas target assembly for neutron production via the H-2(d,n)He-3 reaction at a low-energy accelerator facility

    International Nuclear Information System (INIS)

    Feautrier, D.; Smith, D.L.

    1992-03-01

    This report describes the development and testing of a deuterium gas target intended for use at a low-energy accelerator facility to produce neutrons for basic research and various nuclear applications. The principle source reaction is H-2(d,n)He-3. It produces a nearly mono-energetic group of neutrons. However, a lower-energy continuum neutron spectrum is produced by the H-2(d;n,p)H-2 reaction and also by deuterons which strike various components in the target assembly. The present target is designed to achieve the following objectives: (1) minimize unwanted background neutron production from the target assembly, (2) provide a relatively low level of residual long-term activity within the target components, (3) have the capacity to dissipate up to 150 watts of beam power with good target longevity, and (4) possess a relatively modest target mass in order to minimize neutron scattering from the target components. The basic physical principles that have to be considered in designing an accelerator target are discussed and the major engineering features of this particular target design are outlined. The results of initial performance tests on this target are documented and some conclusions concerning the viability of the target design are presented

  15. Expression of human Piwi-like genes is associated with prognosis for soft tissue sarcoma patients

    International Nuclear Information System (INIS)

    Greither, Thomas; Taubert, Helge; Koser, Franziska; Kappler, Matthias; Bache, Matthias; Lautenschläger, Christine; Göbel, Steffen; Holzhausen, Hans-Jürgen; Wach, Sven; Würl, Peter

    2012-01-01

    Argonaute genes are essential for RNA interference, stem cell maintenance and differentiation. The Piwi-like genes, a subclass of the Argonaute genes, are expressed mainly in the germline. These genes may be re-expressed in tumors, and expression of the Piwi-like genes is associated with prognosis in several types of tumors. We measured the expression of Piwi-like mRNAs (Piwi-like 2–4) in 125 soft tissue sarcoma (STS) samples by qPCRs. Statistical tests were applied to study the correlation of expression levels with tumor-specific survival for STS patients. In multivariate Cox’s regression analyses, we showed that low Piwi-like 2 and Piwi-like 4 mRNA expression were significantly associated with a worse prognosis (RR = 1.87; p = 0.032 and RR = 1.82; p = 0.039). Low expression of both genes was associated with a 2.58-fold increased risk of tumor-related death (p = 0.01). Piwi-like 4 and combined Piwi-like 2 and 4 mRNA levels correlated significantly with prognosis (RR = 3.53; p = 0.002 and RR = 5.23; p = 0.004) only for female but not for male patients. However, combined low Piwi-like 2 and 3 transcript levels were associated with worse survival (RR = 5.90; p = 0.02) for male patients. In this study, we identified a significant association between the expression of Piwi-like 2 and 4 mRNAs and the tumor-specific survival of soft tissue sarcoma patients. Furthermore, a connection between sex and the impact of Piwi-like mRNA expressions on STS patients’ prognosis was shown for the first time

  16. Sparing Healthy Tissue and Increasing Tumor Dose Using Bayesian Modeling of Geometric Uncertainties for Planning Target Volume Personalization

    International Nuclear Information System (INIS)

    Herschtal, Alan; Te Marvelde, Luc; Mengersen, Kerrie; Foroudi, Farshad; Eade, Thomas; Pham, Daniel; Caine, Hannah; Kron, Tomas

    2015-01-01

    Objective: To develop a mathematical tool that can update a patient's planning target volume (PTV) partway through a course of radiation therapy to more precisely target the tumor for the remainder of treatment and reduce dose to surrounding healthy tissue. Methods and Materials: Daily on-board imaging was used to collect large datasets of displacements for patients undergoing external beam radiation therapy for solid tumors. Bayesian statistical modeling of these geometric uncertainties was used to optimally trade off between displacement data collected from previously treated patients and the progressively accumulating data from a patient currently partway through treatment, to optimally predict future displacements for that patient. These predictions were used to update the PTV position and margin width for the remainder of treatment, such that the clinical target volume (CTV) was more precisely targeted. Results: Software simulation of dose to CTV and normal tissue for 2 real prostate displacement datasets consisting of 146 and 290 patients treated with a minimum of 30 fractions each showed that re-evaluating the PTV position and margin width after 8 treatment fractions reduced healthy tissue dose by 19% and 17%, respectively, while maintaining CTV dose. Conclusion: Incorporating patient-specific displacement patterns from early in a course of treatment allows PTV adaptation for the remainder of treatment. This substantially reduces the dose to healthy tissues and thus can reduce radiation therapy–induced toxicities, improving patient outcomes

  17. Sparing Healthy Tissue and Increasing Tumor Dose Using Bayesian Modeling of Geometric Uncertainties for Planning Target Volume Personalization

    Energy Technology Data Exchange (ETDEWEB)

    Herschtal, Alan, E-mail: Alan.Herschtal@petermac.org [Department of Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne (Australia); Faculty of Health, Arts and Design, Swinburne University of Technology, Melbourne (Australia); Te Marvelde, Luc [Department of Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne (Australia); Mengersen, Kerrie [School of Mathematical Sciences, Science and Engineering Faculty, Queensland University of Technology, Brisbane (Australia); Foroudi, Farshad [Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne (Australia); The Sir Peter MacCallum Department of Oncology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne (Australia); Eade, Thomas [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St. Leonards, Sydney (Australia); Northern Clinical School, University of Sydney (Australia); Pham, Daniel [Department of Radiation Therapy, Peter MacCallum Cancer Centre, Melbourne (Australia); Caine, Hannah [Northern Sydney Cancer Centre, Radiation Oncology Department, Royal North Shore Hospital, St. Leonards, Sydney (Australia); Kron, Tomas [The Sir Peter MacCallum Department of Oncology, Faculty of Medicine, Dentistry and Health Sciences, University of Melbourne, Melbourne (Australia); Department of Physical Sciences, Peter MacCallum Cancer Centre, Melbourne (Australia)

    2015-06-01

    Objective: To develop a mathematical tool that can update a patient's planning target volume (PTV) partway through a course of radiation therapy to more precisely target the tumor for the remainder of treatment and reduce dose to surrounding healthy tissue. Methods and Materials: Daily on-board imaging was used to collect large datasets of displacements for patients undergoing external beam radiation therapy for solid tumors. Bayesian statistical modeling of these geometric uncertainties was used to optimally trade off between displacement data collected from previously treated patients and the progressively accumulating data from a patient currently partway through treatment, to optimally predict future displacements for that patient. These predictions were used to update the PTV position and margin width for the remainder of treatment, such that the clinical target volume (CTV) was more precisely targeted. Results: Software simulation of dose to CTV and normal tissue for 2 real prostate displacement datasets consisting of 146 and 290 patients treated with a minimum of 30 fractions each showed that re-evaluating the PTV position and margin width after 8 treatment fractions reduced healthy tissue dose by 19% and 17%, respectively, while maintaining CTV dose. Conclusion: Incorporating patient-specific displacement patterns from early in a course of treatment allows PTV adaptation for the remainder of treatment. This substantially reduces the dose to healthy tissues and thus can reduce radiation therapy–induced toxicities, improving patient outcomes.

  18. Target-like pigmentation after minipunch grafting in stable vitiligo

    Directory of Open Access Journals (Sweden)

    Nelee Bisen

    2014-01-01

    Full Text Available Surgical treatment for vitiligo has been ever evolving. Each surgical modality has its own benefits and limitations. Miniature punch grafting is the most extensively performed surgery, which gives good results in stable vitiligo. Herein we report an unusual type of repigmentation observed after minipunch grafting in a patient of stable vitiligo, which resembled target-like lesions with a "perigraft halo" surrounding individual grafts. Such pigment spread occurred despite the use of 0.5 mm larger graft from the donor site.

  19. Mechanisms involved in the transport of mercuric ions in target tissues

    Science.gov (United States)

    Bridges, Christy C.; Zalups, Rudolfs K.

    2016-01-01

    Mercury exists in the environment in various forms, all of which pose a risk to human health. Despite guidelines regulating the industrial release of mercury into the environment, humans continue to be exposed regularly to various forms of this metal via inhalation or ingestion. Following exposure, mercuric ions are taken up by and accumulate in numerous organs, including brain, intestine, kidney, liver, and placenta. In order to understand the toxicological effects of exposure to mercury, a thorough understanding of the mechanisms that facilitate entry of mercuric ions into target cells must first be obtained. A number of mechanisms for the transport of mercuric ions into target cells and organs have been proposed in recent years. However, the ability of these mechanisms to transport mercuric ions and the regulatory features of these carriers have not been characterized completely. The purpose of this review is to summarize the current findings related to the mechanisms that may be involved in the transport of inorganic and organic forms of mercury in target tissues and organs. This review will describe mechanisms known to be involved in the transport of mercury and will also propose additional mechanisms that may potentially be involved in the transport of mercuric ions into target cells. PMID:27422290

  20. Aligned and Electrospun Piezoelectric Polymer Fiber Assembly and Scaffold

    Science.gov (United States)

    Scott-Carnell, Lisa A. (Inventor); Siochi, Emilie J. (Inventor); Holloway, Nancy M. (Inventor); Leong, Kam W. (Inventor); Kulangara, Karina (Inventor)

    2015-01-01

    A scaffold assembly and related methods of manufacturing and/or using the scaffold for stem cell culture and tissue engineering applications are disclosed which at least partially mimic a native biological environment by providing biochemical, topographical, mechanical and electrical cues by using an electroactive material. The assembly includes at least one layer of substantially aligned, electrospun polymer fiber having an operative connection for individual voltage application. A method of cell tissue engineering and/or stem cell differentiation uses the assembly seeded with a sample of cells suspended in cell culture media, incubates and applies voltage to one or more layers, and thus produces cells and/or a tissue construct. In another aspect, the invention provides a method of manufacturing the assembly including the steps of providing a first pre-electroded substrate surface; electrospinning a first substantially aligned polymer fiber layer onto the first surface; providing a second pre-electroded substrate surface; electrospinning a second substantially aligned polymer fiber layer onto the second surface; and, retaining together the layered surfaces with a clamp and/or an adhesive compound.

  1. NOD-Like Receptors in Intestinal Homeostasis and Epithelial Tissue Repair

    Science.gov (United States)

    Parlato, Marianna; Yeretssian, Garabet

    2014-01-01

    The intestinal epithelium constitutes a dynamic physical barrier segregating the luminal content from the underlying mucosal tissue. Following injury, the epithelial integrity is restored by rapid migration of intestinal epithelial cells (IECs) across the denuded area in a process known as wound healing. Hence, through a sequence of events involving restitution, proliferation and differentiation of IECs the gap is resealed and homeostasis reestablished. Relapsing damage followed by healing of the inflamed mucosa is a hallmark of several intestinal disorders including inflammatory bowel diseases (IBD). While several regulatory peptides, growth factors and cytokines stimulate restitution of the epithelial layer after injury, recent evidence in the field underscores the contribution of innate immunity in controlling this process. In particular, nucleotide-binding and oligomerization domain-like receptors (NLRs) play critical roles in sensing the commensal microbiota, maintaining homeostasis, and regulating intestinal inflammation. Here, we review the process of intestinal epithelial tissue repair and we specifically focus on the impact of NLR-mediated signaling mechanisms involved in governing epithelial wound healing during disease. PMID:24886810

  2. Value of the radiolabelled GLP-1 receptor antagonist exendin(9-39) for targeting of GLP-1 receptor-expressing pancreatic tissues in mice and humans

    Energy Technology Data Exchange (ETDEWEB)

    Waser, Beatrice; Reubi, Jean Claude [University of Berne, Division of Cell Biology and Experimental Cancer Research, Institute of Pathology, P.O. Box 62, Bern (Switzerland)

    2011-06-15

    Radiolabelled glucagon-like peptide 1 (GLP-1) receptor agonists have recently been shown to successfully image benign insulinomas in patients. Moreover, it was recently reported that antagonist tracers were superior to agonist tracers for somatostatin and gastrin-releasing peptide receptor targeting of tumours. The present preclinical study determines therefore the value of an established GLP-1 receptor antagonist for the in vitro visualization of GLP-1 receptor-expressing tissues in mice and humans. Receptor autoradiography studies with {sup 125}I-GLP-1(7-36)amide agonist or {sup 125}I-Bolton-Hunter-exendin(9-39) antagonist radioligands were performed in mice pancreas and insulinomas as well as in human insulinomas; competition experiments were performed in the presence of increasing concentration of GLP-1(7-36)amide or exendin(9-39). The antagonist {sup 125}I-Bolton-Hunter-exendin(9-39) labels mouse pancreatic {beta}-cells and mouse insulinomas, but it does not label human pancreatic {beta}-cells and insulinomas. High affinity displacement (IC{sub 50} approximately 2 nM) is observed in mouse {beta}-cells and insulinomas with either the exendin(9-39) antagonist or GLP-1(7-36)amide agonist. For comparison, the agonist {sup 125}I-GLP-1(7-36)amide intensively labels mouse pancreatic {beta}-cells, mouse insulinoma and human insulinomas; high affinity displacement is observed for the GLP-1(7-36)amide in all tissues; however, a 5 and 20 times lower affinity is found for exendin(9-39) in the mouse and human tissues, respectively. This study reports a species-dependent behaviour of the GLP-1 receptor antagonist exendin(9-39) that can optimally target GLP-1 receptors in mice but not in human tissue. Due to its overly low binding affinity, this antagonist is an inadequate targeting agent for human GLP-1 receptor-expressing tissues, as opposed to the GLP-1 receptor agonist, GLP-1(7-36)amide. (orig.)

  3. Enzyme sensitive smart inulin-dehydropeptide conjugate self-assembles into nanostructures useful for targeted delivery of ornidazole.

    Science.gov (United States)

    Shivhare, Kriti; Garg, Charu; Priyam, Ayushi; Gupta, Alka; Sharma, Ashwani Kumar; Kumar, Pradeep

    2018-01-01

    Molecular self-assembly of biodegradable amphiphilic polymers allows rational design of biocompatible nanomaterials for drug delivery. Use of substituted polysaccharides for such applications offers the ease of design and synthesis, and provides higher biofunctionality and biocompatibility to nanomaterials. The present work focuses on the synthesis, characterization and potential biomedical applications of self-assembled polysaccharide-based materials. We demonstrated that the synthesized amphiphilic inulin self-assembled in aqueous medium into nanostructures with average size in the range of 146-486nm and encapsulated hydrophobic therapeutic molecule, ornidazole. Hydrophophic dehydropeptide was conjugated with inulin via a biocompatible ester linkage. Dehydrophenylalanine, an unusual amino acid, was incorporated in the peptide to make it stable at a broader range of pH as well as against proteases. The resulting core-shell type of nanostructures could encapsulate ornidazole in the hydrophobic core and released it in a controlled fashion. By taking the advantage of inulin, which gets degraded in the colon by colonic bacteria, the effect of enzyme, inulinase, present in the microflora of the large intestine, on inulin-peptide degradation followed by drug release has been studied. Altogether, small peptide conjugated to inulin offers novel scaffold for the future design of nanostructures with potential applications in the field of targeted drug delivery. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Self-assembled nanoparticles based on the c(RGDfk peptide for the delivery of siRNA targeting the VEGFR2 gene for tumor therapy

    Directory of Open Access Journals (Sweden)

    Liu L

    2014-07-01

    Full Text Available Li Liu,1 Xiaoxia Liu,1 Qian Xu,1 Ping Wu,2 Xialin Zuo,3 Jingjing Zhang,1 Houliang Deng,1 Zhuomin Wu,1 Aimin Ji1 1Department of Pharmacy, Zhujiang Hospital, Southern Medical University, Guangzhou, People’s Republic of China; 2Department of Pharmacy, Chengdu Integrated TCM & Western Medicine Hospital, Chengdu, People’s Republic of China; 3Institute of Neurosciences and the Second Affiliated Hospital of Guangzhou Medical University, Key Laboratory of Neurogenetics and Channelopathies of Guangdong Province and the Ministry of Education of China, Guangzhou, People’s Republic of China Abstract: The clinical application of small interfering RNA (siRNA has been restricted by their poor intracellular uptake, low serum stability, and inability to target specific cells. During the last several decades, a great deal of effort has been devoted to exploring materials for siRNA delivery. In this study, biodegradable, tumor-targeted, self-assembled peptide nanoparticles consisting of cyclo(Arg–Gly–Asp–d–Phe–Lys-8–amino–3,6–dioxaoctanoic acid–β–maleimidopropionic acid (hereafter referred to as RPM were found to be an effective siRNA carrier both in vitro and in vivo. The nanoparticles were characterized based on transmission electron microscopy, circular dichroism spectra, and dynamic light scattering. In vitro analyses showed that the RPM/VEGFR2-siRNA exhibited negligible cytotoxicity and induced effective gene silencing. Delivery of the RPM/VEGFR2 (zebrafish-siRNA into zebrafish embryos resulted in inhibition of neovascularization. Administration of RPM/VEGFR2 (mouse-siRNA to tumor-bearing nude mice led to a significant inhibition of tumor growth, a marked reduction of vessels, and a downregulation of VEGFR2 (messenger RNA and protein in tumor tissue. Furthermore, the levels of IFN-α, IFN-γ, IL-12, and IL-6 in mouse serum, assayed via enzyme-linked immunosorbent assay, did not indicate any immunogenicity of the RPM/VEGFR2

  5. Mitomycin C dissolved in a reversible thermosetting gel: target tissue concentrations in the rabbit eye.

    Science.gov (United States)

    Ichien, K; Yamamoto, T; Kitazawa, Y; Oguri, A; Ando, H; Kondo, Y

    1997-01-01

    To determine whether a new, reversible thermosetting gel enhances mitomycin C transfer to target ocular tissues in the rabbit eye. A 0.1 ml solution of mitomycin C containing 0.22 microgram, 2.9 micrograms, or 28 micrograms of the agent dissolved in a reversible thermosetting gel consisting of methylcellulose, citric acid, and polyethylene glycol was injected subconjunctivally in 30 New Zealand albino rabbits. Scleral and conjunctival tissues were excised at 0.5, 1, 2, 4, or 24 hours after the injection and mitomycin C concentrations in these tissues were determined by high performance liquid chromatography. The concentration over time was approximated to a single exponential curve, and initial mitomycin C concentrations, time constants, and half life values were determined. Finally, the areas under the curves (AUCs) between 0.5 and 24 hours were calculated. The mitomycin C concentrations in the target tissues were dose dependent and decreased rapidly over 24 hours. Both the initial mitomycin C concentrations as well as AUCs in these eyes treated with mitomycin C, dissolved in a reversible thermosetting gel, were higher than those in eyes treated similarly in a previous study in which the gel was not used. Applied subconjunctivally in the rabbit eye, mitomycin C dissolved in the reversible thermosetting gel enhanced transfer of the agent to the sclera and the conjunctiva.

  6. Endogenous inotropic substance from heart tissue has digitalis-like properties

    Energy Technology Data Exchange (ETDEWEB)

    Khatter, J.C.; Agbanyo, M.; Navaratnam, S. (Univ. of Manitoba, Winnipeg (Canada))

    1991-01-01

    In the past few years, we developed an extraction procedure which we successfully used to isolate a crude fraction containing digitalis-like substance (DLS) from porcine left ventricular tissue. In this study, the crude fraction was found to cross-react with digoxin antibodies and showed immunoreactivity of 4.25 {plus minus} 0.6 ng digoxin equivalent/ml. On further purification of the crude fraction using silica gel G column chromatography, a fraction C was obtained, which was highly positive inotropic on canine trabeculae and it dose-dependently inhibited ouabain sensitive {sup 86}Rb{sup +} uptake in rate heart slices. A 50% inhibition of uptake was obtained by 25 ul of fraction C. Fraction C also inhibited canine kidney Na{sup +}, K{sup +}-ATPase dose-dependently and a 50% inhibition of this enzyme required 17 ul of fraction C. Ashing of the fraction C at 500{degree}C resulted in loss of inotropic and enzyme inhibitory activities, indicating an organic nature of the unknown digitalis-like substance.

  7. DNA mediated wire-like clusters of self-assembled TiO2 nanomaterials: supercapacitor and dye sensitized solar cell applications

    Science.gov (United States)

    Nithiyanantham, U.; Ramadoss, Ananthakumar; Ede, Sivasankara Rao; Kundu, Subrata

    2014-06-01

    A new route for the formation of wire-like clusters of TiO2 nanomaterials self-assembled in DNA scaffold within an hour of reaction time is reported. TiO2 nanomaterials are synthesized by the reaction of titanium-isopropoxide with ethanol and water in the presence of DNA under continuous stirring and heating at 60 °C. The individual size of the TiO2 NPs self-assembled in DNA and the diameter of the wires can be tuned by controlling the DNA to Ti-salt molar ratios and other reaction parameters. The eventual diameter of the individual particles varies between 15 +/- 5 nm ranges, whereas the length of the nanowires varies in the 2-3 μm range. The synthesized wire-like DNA-TiO2 nanomaterials are excellent materials for electrochemical supercapacitor and DSSC applications. From the electrochemical supercapacitor experiment, it was found that the TiO2 nanomaterials showed different specific capacitance (Cs) values for the various nanowires, and the order of Cs values are as follows: wire-like clusters (small size) > wire-like clusters (large size). The highest Cs of 2.69 F g-1 was observed for TiO2 having wire-like structure with small sizes. The study of the long term cycling stability of wire-like clusters (small size) electrode were shown to be stable, retaining ca. 80% of the initial specific capacitance, even after 5000 cycles. The potentiality of the DNA-TiO2 nanomaterials was also tested in photo-voltaic applications and the observed efficiency was found higher in the case of wire-like TiO2 nanostructures with larger sizes compared to smaller sizes. In future, the described method can be extended for the synthesis of other oxide based materials on DNA scaffold and can be further used in other applications like sensors, Li-ion battery materials or treatment for environmental waste water.A new route for the formation of wire-like clusters of TiO2 nanomaterials self-assembled in DNA scaffold within an hour of reaction time is reported. TiO2 nanomaterials are

  8. Polymer Directed Protein Assemblies

    Directory of Open Access Journals (Sweden)

    Patrick van Rijn

    2013-05-01

    Full Text Available Protein aggregation and protein self-assembly is an important occurrence in natural systems, and is in some form or other dictated by biopolymers. Very obvious influences of biopolymers on protein assemblies are, e.g., virus particles. Viruses are a multi-protein assembly of which the morphology is dictated by poly-nucleotides namely RNA or DNA. This “biopolymer” directs the proteins and imposes limitations on the structure like the length or diameter of the particle. Not only do these bionanoparticles use polymer-directed self-assembly, also processes like amyloid formation are in a way a result of directed protein assembly by partial unfolded/misfolded biopolymers namely, polypeptides. The combination of proteins and synthetic polymers, inspired by the natural processes, are therefore regarded as a highly promising area of research. Directed protein assembly is versatile with respect to the possible interactions which brings together the protein and polymer, e.g., electrostatic, v.d. Waals forces or covalent conjugation, and possible combinations are numerous due to the large amounts of different polymers and proteins available. The protein-polymer interacting behavior and overall morphology is envisioned to aid in clarifying protein-protein interactions and are thought to entail some interesting new functions and properties which will ultimately lead to novel bio-hybrid materials.

  9. Normal tissue dose-effect models in biological dose optimisation

    International Nuclear Information System (INIS)

    Alber, M.

    2008-01-01

    Sophisticated radiotherapy techniques like intensity modulated radiotherapy with photons and protons rely on numerical dose optimisation. The evaluation of normal tissue dose distributions that deviate significantly from the common clinical routine and also the mathematical expression of desirable properties of a dose distribution is difficult. In essence, a dose evaluation model for normal tissues has to express the tissue specific volume effect. A formalism of local dose effect measures is presented, which can be applied to serial and parallel responding tissues as well as target volumes and physical dose penalties. These models allow a transparent description of the volume effect and an efficient control over the optimum dose distribution. They can be linked to normal tissue complication probability models and the equivalent uniform dose concept. In clinical applications, they provide a means to standardize normal tissue doses in the face of inevitable anatomical differences between patients and a vastly increased freedom to shape the dose, without being overly limiting like sets of dose-volume constraints. (orig.)

  10. The molecular mechanisms of signaling by cooperative assembly formation in innate immunity pathways.

    Science.gov (United States)

    Vajjhala, Parimala R; Ve, Thomas; Bentham, Adam; Stacey, Katryn J; Kobe, Bostjan

    2017-06-01

    The innate immune system is the first line of defense against infection and responses are initiated by pattern recognition receptors (PRRs) that detect pathogen-associated molecular patterns (PAMPs). PRRs also detect endogenous danger-associated molecular patterns (DAMPs) that are released by damaged or dying cells. The major PRRs include the Toll-like receptor (TLR) family members, the nucleotide binding and oligomerization domain, leucine-rich repeat containing (NLR) family, the PYHIN (ALR) family, the RIG-1-like receptors (RLRs), C-type lectin receptors (CLRs) and the oligoadenylate synthase (OAS)-like receptors and the related protein cyclic GMP-AMP synthase (cGAS). The different PRRs activate specific signaling pathways to collectively elicit responses including the induction of cytokine expression, processing of pro-inflammatory cytokines and cell-death responses. These responses control a pathogenic infection, initiate tissue repair and stimulate the adaptive immune system. A central theme of many innate immune signaling pathways is the clustering of activated PRRs followed by sequential recruitment and oligomerization of adaptors and downstream effector enzymes, to form higher-order arrangements that amplify the response and provide a scaffold for proximity-induced activation of the effector enzymes. Underlying the formation of these complexes are co-operative assembly mechanisms, whereby association of preceding components increases the affinity for downstream components. This ensures a rapid immune response to a low-level stimulus. Structural and biochemical studies have given key insights into the assembly of these complexes. Here we review the current understanding of assembly of immune signaling complexes, including inflammasomes initiated by NLR and PYHIN receptors, the myddosomes initiated by TLRs, and the MAVS CARD filament initiated by RIG-1. We highlight the co-operative assembly mechanisms during assembly of each of these complexes. Copyright

  11. PREFACE The physics of virus assembly The physics of virus assembly

    Science.gov (United States)

    Stockley, Peter G.; Twarock, Reidun

    2010-12-01

    Viruses are pathogens in every kingdom of life and are major causes of human disease and suffering. They are known to encompass a size range that overlaps with that of the smallest bacterial cells, and the largest viruses now seem to be hosts of their own viral pathogens. Recent genomic sequencing efforts show that many organisms have genes that are likely to be descended in evolution from viral progenitors. Even more astonishingly, analysis of the world's oceans has shown that some of the simplest viruses, the tailed dsDNA phages, are the most common biological entities on the planet, with estimates of their numbers ranging up to 1031, with ~ 1021 infection events every second, leading to a turnover of around 20% of the biomass in the sea every few days. These cycles of infection and lysis of oceanic bacteria and algae provide the nutrients for the smallest organisms lying at the bottom of the food chain. Without viruses, therefore, life on Earth would probably not be sustainable. These are remarkable facts for systems that are non-living in the strict sense, and are composed of simple materials—nucleic acids, proteins and lipids. Many viruses consist of little more than a protective protein coat surrounding their genomic nucleic acids, which can be either DNA or RNA. Their simplicity leads to highly symmetrical structures with protein containers based on helical or icosahedral lattices. Many simple viruses self-assemble rapidly and with great fidelity, and many groups are busy trying to exploit these properties to make virus-like particles for a wide range of applications, including targeted drug-delivery, medical imaging and even novel materials. This issue of Physical Biology contains a series of papers describing some of the latest experimental and theoretical research on viruses, their structures and assembly, as well as their regulated disassembly during infection. These range from a dissection of the in vivo assembly mechanism of a filamentous virus

  12. Modular Assembly of Cell-targeting Devices Based on an Uncommon G-quadruplex Aptamer

    DEFF Research Database (Denmark)

    Opazo, Felipe; Eiden, Laura; Hansen, Line

    2015-01-01

    cells. We further optimized this aptamer to a highly versatile and stable minimized version. The minimized aptamer can be easily equipped with different functionalities like quantum dots, organic dyes, or even a second different aptamer domain yielding a bi-paratopic aptamer. Although the target...

  13. Modulated growth, stability and interactions of liquid-like coacervate assemblies of elastin

    NARCIS (Netherlands)

    Muiznieks, L.D.; Cirulis, J.T.; Reinhardt, D.P.; Wuite, G.J.L.; Pomes, R.; Keeley, F.W.

    2014-01-01

    Elastin self-assembles from monomers into polymer networks that display elasticity and resilience. The first major step in assembly is a liquid-liquid phase separation known as coacervation. This process represents a continuum of stages from initial phase separation to early growth of droplets by

  14. Antiproton Target

    CERN Multimedia

    1980-01-01

    Antiproton target used for the AA (antiproton accumulator). The first type of antiproton production target used from 1980 to 1982 comprised a rod of copper 3mm diameter and 120mm long embedded in a graphite cylinder that was itself pressed into a finned aluminium container. This assembly was air-cooled and it was used in conjunction with the Van der Meer magnetic horn. In 1983 Fermilab provided us with lithium lenses to replace the horn with a view to increasing the antiproton yield by about 30%. These lenses needed a much shorter target made of heavy metal - iridium was chosen for this purpose. The 50 mm iridium rod was housed in an extension to the original finned target container so that it could be brought very close to the entrance to the lithium lens. Picture 1 shows this target assembly and Picture 2 shows it mounted together with the lithium lens. These target containers had a short lifetime due to a combination of beam heating and radiation damage. This led to the design of the water-cooled target in...

  15. Adult soft tissue sarcomas: conventional therapies and molecularly targeted approaches.

    Science.gov (United States)

    Mocellin, Simone; Rossi, Carlo R; Brandes, Alba; Nitti, Donato

    2006-02-01

    The therapeutic approach to soft tissue sarcomas (STS) has evolved over the past two decades based on the results from randomized controlled trials, which are guiding physicians in the treatment decision-making process. Despite significant improvements in the control of local disease, a significant number of patients ultimately die of recurrent/metastatic disease following radical surgery due to a lack of effective adjuvant treatments. In addition, the characteristic chemoresistance of STS has compromised the therapeutic value of conventional antineoplastic agents in cases of unresectable advanced/metastatic disease. Therefore, novel therapeutic strategies are urgently needed to improve the prognosis of patients with STS. Recent advances in STS biology are paving the way to the development of molecularly targeted therapeutic strategies, the efficacy of which relies not only on the knowledge of the molecular mechanisms underlying cancer development/progression but also on the personalization of the therapeutic regimen according to the molecular features of individual tumours. In this work, we review the state-of-the-art of conventional treatments for STS and summarize the most promising findings in the development of molecularly targeted therapeutic approaches.

  16. Effects of insulin-like growth factor-1 on the assembly and secretion of very low-density lipoproteins in cow hepatocytes in vitro.

    Science.gov (United States)

    Li, Xinwei; Guan, Yuan; Li, Ying; Wu, Dianjun; Liu, Lei; Deng, Qinghua; Li, Xiaobing; Wang, Zhe; Liu, Guowen

    2016-01-15

    Fatty liver is a major metabolic disorder of dairy cows. One important reason is that hepatic very low-density lipoproteins (VLDL) assembly was significant decreased in dairy cows with fatty liver. In addition, the impairment of insulin-like growth factor (IGF)-1 synthesis was involved in the development of fatty liver. Therefore, the objective of this study was to investigate the effects of IGF-1 on the VLDL assembly in cow hepatocytes. In this study, cow hepatocytes were cultured and then transfected with Ad-GFP-IGF-1 (inhibited the IGF-1 expression) and Ad-GFP (negative control), and treated with different concentrations of IGF-1, respectively. The results showed that IGF-1 increased the mRNA abundance of apolipoprotein B100 (ApoB100), apolipoprotein E (ApoE), microsomal triglyceride transfer protein (MTTP), and low-density lipoprotein receptor (LDLR) and then increased the VLDL assembly in cow hepatocytes. Nevertheless, impairment of IGF-1 expression by Ad-GFP-IGF-1 could inhibit above genes expression and VLDL assembly in hepatocytes. Taken together, these results indicate that IGF-1 increases the VLDL assembly and impairment of IGF-1 expression decreases the VLDL assembly in cow hepatocytes. Copyright © 2016 Elsevier Inc. All rights reserved.

  17. Targeting diseased tissues by pHLIP insertion at low cell surface pH

    Directory of Open Access Journals (Sweden)

    Oleg A. Andreev

    2014-03-01

    Full Text Available The discovery of the pH Low Insertion Peptides (pHLIPs provides an opportunity to develop imaging and drug delivery agents targeting extracellular acidity. Extracellular acidity is associated with many pathological states, such as those in cancer, ischemic stroke, neurotrauma, infection, lacerations and others. The metabolism of cells in injured or diseased tissues often results in the acidification of the extracellular environment, so acidosis might be useful as a general marker for the imaging and treatment of diseased states if an effective targeting method can be developed. The molecular mechanism of a pHLIP peptide is based on pH-dependent membrane-associated folding. pHLIPs, being moderately hydrophobic peptides, have high affinities for cellular membranes at normal pH, but fold and insert across membranes at low pH, allowing them to sense pH at the surfaces of cells in diseased tissues, where it is the lowest. Here we discuss the main principles of pHLIP interactions with membrane lipid bilayers at neutral and low pHs, the possibility of tuning the folding and insertion pH by peptide sequence variation, and potential applications of pHLIPs for imaging, therapy and image-guided interventions.

  18. Targeting diseased tissues by pHLIP insertion at low cell surface pH.

    Science.gov (United States)

    Andreev, Oleg A; Engelman, Donald M; Reshetnyak, Yana K

    2014-01-01

    The discovery of the pH Low Insertion Peptides (pHLIPs®) provides an opportunity to develop imaging and drug delivery agents targeting extracellular acidity. Extracellular acidity is associated with many pathological states, such as those in cancer, ischemic stroke, neurotrauma, infection, lacerations, and others. The metabolism of cells in injured or diseased tissues often results in the acidification of the extracellular environment, so acidosis might be useful as a general marker for the imaging and treatment of diseased states if an effective targeting method can be developed. The molecular mechanism of a pHLIP peptide is based on pH-dependent membrane-associated folding. pHLIPs, being moderately hydrophobic peptides, have high affinities for cellular membranes at normal pH, but fold and insert across membranes at low pH, allowing them to sense pH at the surfaces of cells in diseased tissues, where it is the lowest. Here we discuss the main principles of pHLIP interactions with membrane lipid bilayers at neutral and low pHs, the possibility of tuning the folding and insertion pH by peptide sequence variation, and potential applications of pHLIPs for imaging, therapy and image-guided interventions.

  19. Intraflagellar Transport (IFT) Role in Ciliary Assembly, Resorption and Signalling

    DEFF Research Database (Denmark)

    Pedersen, Lotte B; Rosenbaum, Joel L

    2008-01-01

    Cilia and flagella have attracted tremendous attention in recent years as research demonstrated crucial roles for these organelles in coordinating a number of physiologically and developmentally important signaling pathways, including the platelet-derived growth factor receptor (PDGFR) alpha, Sonic...... hedgehog, polycystin, and Wnt pathways. In addition, the realization that defective assembly or function of cilia can cause a plethora of diseases and developmental defects ("ciliopathies") has increased focus on the mechanisms by which these antenna-like, microtubular structures assemble. Ciliogenesis...... mechanisms and functions of IFT. In addition to a general, up-to-date description of IFT, we discuss mechanisms by which proteins are selectively targeted to the ciliary compartment, with special focus on the ciliary transition zone. Finally, we briefly review the role of IFT in cilia-mediated signaling...

  20. The Cell Cycle Timing of Centromeric Chromatin Assembly in Drosophila Meiosis Is Distinct from Mitosis Yet Requires CAL1 and CENP-C

    Science.gov (United States)

    Gorgescu, Walter; Tang, Jonathan; Costes, Sylvain V.; Karpen, Gary H.

    2012-01-01

    CENP-A (CID in flies) is the histone H3 variant essential for centromere specification, kinetochore formation, and chromosome segregation during cell division. Recent studies have elucidated major cell cycle mechanisms and factors critical for CENP-A incorporation in mitosis, predominantly in cultured cells. However, we do not understand the roles, regulation, and cell cycle timing of CENP-A assembly in somatic tissues in multicellular organisms and in meiosis, the specialized cell division cycle that gives rise to haploid gametes. Here we investigate the timing and requirements for CID assembly in mitotic tissues and male and female meiosis in Drosophila melanogaster, using fixed and live imaging combined with genetic approaches. We find that CID assembly initiates at late telophase and continues during G1 phase in somatic tissues in the organism, later than the metaphase assembly observed in cultured cells. Furthermore, CID assembly occurs at two distinct cell cycle phases during male meiosis: prophase of meiosis I and after exit from meiosis II, in spermatids. CID assembly in prophase I is also conserved in female meiosis. Interestingly, we observe a novel decrease in CID levels after the end of meiosis I and before meiosis II, which correlates temporally with changes in kinetochore organization and orientation. We also demonstrate that CID is retained on mature sperm despite the gross chromatin remodeling that occurs during protamine exchange. Finally, we show that the centromere proteins CAL1 and CENP-C are both required for CID assembly in meiosis and normal progression through spermatogenesis. We conclude that the cell cycle timing of CID assembly in meiosis is different from mitosis and that the efficient propagation of CID through meiotic divisions and on sperm is likely to be important for centromere specification in the developing zygote. PMID:23300382

  1. Amyloid-like protein inclusions in tobacco transgenic plants.

    Directory of Open Access Journals (Sweden)

    Anna Villar-Piqué

    Full Text Available The formation of insoluble protein deposits in human tissues is linked to the onset of more than 40 different disorders, ranging from dementia to diabetes. In these diseases, the proteins usually self-assemble into ordered β-sheet enriched aggregates known as amyloid fibrils. Here we study the structure of the inclusions formed by maize transglutaminase (TGZ in the chloroplasts of tobacco transplastomic plants and demonstrate that they have an amyloid-like nature. Together with the evidence of amyloid structures in bacteria and fungi our data argue that amyloid formation is likely a ubiquitous process occurring across the different kingdoms of life. The discovery of amyloid conformations inside inclusions of genetically modified plants might have implications regarding their use for human applications.

  2. Generalized superradiant assembly for nanophotonic thermal emitters

    Science.gov (United States)

    Mallawaarachchi, Sudaraka; Gunapala, Sarath D.; Stockman, Mark I.; Premaratne, Malin

    2018-03-01

    Superradiance explains the collective enhancement of emission, observed when nanophotonic emitters are arranged within subwavelength proximity and perfect symmetry. Thermal superradiant emitter assemblies with variable photon far-field coupling rates are known to be capable of outperforming their conventional, nonsuperradiant counterparts. However, due to the inability to account for assemblies comprising emitters with various materials and dimensional configurations, existing thermal superradiant models are inadequate and incongruent. In this paper, a generalized thermal superradiant assembly for nanophotonic emitters is developed from first principles. Spectral analysis shows that not only does the proposed model outperform existing models in power delivery, but also portrays unforeseen and startling characteristics during emission. These electromagnetically induced transparency like (EIT-like) and superscattering-like characteristics are reported here for a superradiant assembly, and the effects escalate as the emitters become increasingly disparate. The fact that the EIT-like characteristics are in close agreement with a recent experimental observation involving the superradiant decay of qubits strongly bolsters the validity of the proposed model.

  3. Fuel assembly design for APR1400 with low CBC

    Energy Technology Data Exchange (ETDEWEB)

    Hah, Chang Joo, E-mail: changhah@kings.ac.kr [Department of NPP Engineering, KEPCO International Nuclear Graduate School, Ulsan (Korea, Republic of)

    2015-04-29

    APR 1400 is a PWR (Pressurized Water Reactor) with rated power of 3983 MWth and 241 assemblies. Recently, demand for extremely longer cycle up to 24 months is increasing with challenge of higher critical boron concentration (CBC). In this paper, assembly design method of selecting Gd-rods is introduced to reduce CBC. The purpose of the method is to lower the critical boron concentration of the preliminary core loading pattern (PLP), and consequently to achieve more negative or less positive moderator temperature coefficient (MTC). In this method, both the ratio of the number of low-Gd rod to the number of high-Gd rod (r) and assembly average Gd wt% (w) are the decision variables. The target function is the amount of soluble boron concentration reduction, which can be converted to Δk{sub TARGET}. A set of new designed fuel assembly satisfies an objective function, min [f=∑{sub i}(Δk{sub FA}−Δk{sub i})], and enables a final loading pattern to reach a target CBC. The constraints required to determine a set of Δk are physically realizable pair, (r,w), and the sum of Δk of new designed assemblies as close to Δk{sub TARGET} as possible. New Gd-bearing assemblies selected based on valid pairs of (r,w) are replaced with existing assemblies in a PLP. This design methodology is applied to Shin-Kori Unit 3 Cycle 1 used as a reference model. CASMO-3/MASTER code is used for depletion calculation. CASMO-3/MASTER calculations with new designed assemblies produce lower CBC than the expected CBC, proving that the proposed method works successful.

  4. FABRICATION AND CHARACTERIZATION OF FAST IGNITION TARGETS

    International Nuclear Information System (INIS)

    HILL, D.W; CASTILLO, E; CHEN, K.C; GRANT, S.E; GREENWOOD, A.L; KAAE, J.L; NIKROO, A; PAGUIO, S.P; SHEARER, C; SMITH, J.N Jr.; STEPHENS, R.B; STEINMAN, D.A; WALL, J.

    2003-09-01

    OAK-B135 Fast ignition is a novel scheme for achieving laser fusion. A class of these targets involves cone mounted CH shells. The authors have been fabricating such targets with shells with a wide variety of diameters and wall thicknesses for several years at General Atomics. In addition, recently such shells were needed for implosion experiments at Laboratory for Laser Energetics (LLE) that for the first time were required to be gas retentive. Fabrication of these targets requires producing appropriate cones and shells, assembling the targets, and characterization of the assembled targets. The cones are produced using micromachining and plating techniques. The shells are fabricated using the depolymerizable mandrel technique followed by micromachining a hole for the cone. The cone and the shell then need to be assembled properly for gas retention and precisely in order to position the cone tip at the desired position within the shell. Both are critical for the fast ignition experiments. The presence of the cone in the shell creates new challenges in characterization of the assembled targets. Finally, for targets requiring a gas fill, the cone-shell assembly needs to be tested for gas retention and proper strength at the glue joint. This paper presents an overview of the developmental efforts and technical issues addressed during the fabrication of fast ignition targets

  5. Charge neutralization as the major factor for the assembly of nucleocapsid-like particles from C-terminal truncated hepatitis C virus core protein

    Directory of Open Access Journals (Sweden)

    Theo Luiz Ferraz de Souza

    2016-11-01

    Full Text Available Background Hepatitis C virus (HCV core protein, in addition to its structural role to form the nucleocapsid assembly, plays a critical role in HCV pathogenesis by interfering in several cellular processes, including microRNA and mRNA homeostasis. The C-terminal truncated HCV core protein (C124 is intrinsically unstructured in solution and is able to interact with unspecific nucleic acids, in the micromolar range, and to assemble into nucleocapsid-like particles (NLPs in vitro. The specificity and propensity of C124 to the assembly and its implications on HCV pathogenesis are not well understood. Methods Spectroscopic techniques, transmission electron microscopy and calorimetry were used to better understand the propensity of C124 to fold or to multimerize into NLPs when subjected to different conditions or in the presence of unspecific nucleic acids of equivalent size to cellular microRNAs. Results The structural analysis indicated that C124 has low propensity to self-folding. On the other hand, for the first time, we show that C124, in the absence of nucleic acids, multimerizes into empty NLPs when subjected to a pH close to its isoelectric point (pH ≈ 12, indicating that assembly is mainly driven by charge neutralization. Isothermal calorimetry data showed that the assembly of NLPs promoted by nucleic acids is enthalpy driven. Additionally, data obtained from fluorescence correlation spectroscopy show that C124, in nanomolar range, was able to interact and to sequester a large number of short unspecific nucleic acids into NLPs. Discussion Together, our data showed that the charge neutralization is the major factor for the nucleocapsid-like particles assembly from C-terminal truncated HCV core protein. This finding suggests that HCV core protein may physically interact with unspecific cellular polyanions, which may correspond to microRNAs and mRNAs in a host cell infected by HCV, triggering their confinement into infectious particles.

  6. Browning of Subcutaneous White Adipose Tissue in Humans

    OpenAIRE

    Sidossis, Labros S.; Porter, Craig; Saraf, Manish K.; Børsheim, Elisabet; Radhakrishnan, Ravi S.; Chao, Tony; Ali, Arham; Chondronikola, Maria; Mlcak, Ronald; Finnerty, Celeste C.; Hawkins, Hal K.; Toliver-Kinsky, Tracy; Herndon, David N.

    2015-01-01

    Since the presence of brown adipose tissue (BAT) was confirmed in adult humans, BAT has become a therapeutic target for obesity and insulin resistance. We examined whether human subcutaneous white adipose tissue (sWAT) can adopt a BAT-like phenotype using a clinical model of prolonged and severe adrenergic stress. sWAT samples were collected from severely burned and healthy individuals. A subset of burn victims were prospectively followed during their acute hospitalization. Browning of sWAT w...

  7. APT target-blanket fabrication development

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, D.L.

    1997-06-13

    Concepts for producing tritium in an accelerator were translated into hardware for engineering studies of tritium generation, heat transfer, and effects of proton-neutron flux on materials. Small-scale target- blanket assemblies were fabricated and material samples prepared for these performance tests. Blanket assemblies utilize composite aluminum-lead modules, the two primary materials of the blanket. Several approaches are being investigated to produce large-scale assemblies, developing fabrication and assembly methods for their commercial manufacture. Small-scale target-blanket assemblies, designed and fabricated at the Savannah River Site, were place in Los Alamos Neutron Science Center (LANSCE) for irradiation. They were subjected to neutron flux for nine months during 1996-97. Coincident with this test was the development of production methods for large- scale modules. Increasing module size presented challenges that required new methods to be developed for fabrication and assembly. After development, these methods were demonstrated by fabricating and assembling two production-scale modules.

  8. A Rhizobium leguminosarum CHDL- (Cadherin-Like-) Lectin Participates in Assembly and Remodeling of the Biofilm Matrix

    DEFF Research Database (Denmark)

    Vozza, Nicolás F.; Abdian, Patricia L; Russo, Daniela M

    2016-01-01

    In natural environments most bacteria live in multicellular structures called biofilms. These cell aggregates are enclosed in a self-produced polymeric extracellular matrix, which protects the cells, provides mechanical stability and mediates cellular cohesion and adhesion to surfaces. Although...... important advances were made in the identification of the genetic and extracellular factors required for biofilm formation, the mechanisms leading to biofilm matrix assembly, and the roles of extracellular proteins in these processes are still poorly understood. The symbiont Rhizobium leguminosarum requires...... the synthesis of the acidic exopolysaccharide and the PrsDE secretion system to develop a mature biofilm. PrsDE is responsible for the secretion of the Rap family of proteins that share one or two Ra/CHDL (cadherin-like-) domains. RapA2 is a calcium-dependent lectin with a cadherin-like β sheet structure...

  9. Magnetic nanoparticle-based approaches to locally target therapy and enhance tissue regeneration in vivo.

    Science.gov (United States)

    Sensenig, Richard; Sapir, Yulia; MacDonald, Cristin; Cohen, Smadar; Polyak, Boris

    2012-09-01

    Magnetic-based systems utilizing superparamagnetic nanoparticles and a magnetic field gradient to exert a force on these particles have been used in a wide range of biomedical applications. This review is focused on drug targeting applications that require penetration of a cellular barrier as well as strategies to improve the efficacy of targeting in these biomedical applications. Another focus of this review is regenerative applications utilizing tissue engineered scaffolds prepared with the aid of magnetic particles, the use of remote actuation for release of bioactive molecules and magneto-mechanical cell stimulation, cell seeding and cell patterning.

  10. A highly sensitive label-free electrochemical aptasensor for interferon-gamma detection based on graphene controlled assembly and nuclease cleavage-assisted target recycling amplification.

    Science.gov (United States)

    Yan, Genping; Wang, Yonghong; He, Xiaoxiao; Wang, Kemin; Liu, Jinquan; Du, Yudan

    2013-06-15

    We report here a highly sensitive and label-free electrochemical aptasensing technology for detection of interferon-gamma (IFN-γ) based on graphene controlled assembly and enzyme cleavage-assisted target recycling amplification strategy. In this work, in the absence of IFN-γ, the graphene could not be assembled onto the 16-mercaptohexadecanoic acid (MHA) modified gold electrode because the IFN-γ binding aptamer was strongly adsorbed on the graphene due to the strong π-π interaction. Thus the electronic transmission was blocked (eT OFF). However, the presence of target IFN-γ and DNase I led to desorption of aptamer from the graphene surface and further cleavage of the aptamer, thereby releasing the IFN-γ. The released IFN-γ could then re-attack other aptamers on the graphene, resulting in the successive release of the aptamers from the graphene. At the same time, the "naked" graphene could be assembled onto the MHA modified gold electrode with hydrophobic interaction and π-conjunction, mediating the electron transfer between the electrode and the electroactive indicator. Then, measurable electrochemical signals were generated (eT ON), which was related to the concentration of the IFN-γ. By taking advantages of graphene and enzyme cleavage-assisted target recycling amplification, the developed label-free electrochemical aptasensing technology showed a linear response to concentration of IFN-γ range from 0.1 to 0.7 pM. The detection limit of IFN-γ was determined to be 0.065 pM. Moreover, this aptasensor shows good selectivity toward the target in the presence of other relevant proteins. Our strategy thus opens new opportunities for label-free and amplified detection of other kinds of proteins. Copyright © 2013 Elsevier B.V. All rights reserved.

  11. Self-assembled polymeric nanoparticles as new, smart contrast agents for cancer early detection using magnetic resonance imaging.

    Science.gov (United States)

    Mouffouk, Fouzi; Simão, Teresa; Dornelles, Daniel F; Lopes, André D; Sau, Pablo; Martins, Jorge; Abu-Salah, Khalid M; Alrokayan, Salman A; Rosa da Costa, Ana M; dos Santos, Nuno R

    2015-01-01

    Early cancer detection is a major factor in the reduction of mortality and cancer management cost. Here we developed a smart and targeted micelle-based contrast agent for magnetic resonance imaging (MRI), able to turn on its imaging capability in the presence of acidic cancer tissues. This smart contrast agent consists of pH-sensitive polymeric micelles formed by self-assembly of a diblock copolymer (poly(ethyleneglycol-b-trimethylsilyl methacrylate)), loaded with a gadolinium hydrophobic complex ((t)BuBipyGd) and exploits the acidic pH in cancer tissues. In vitro MRI experiments showed that (t)BuBipyGd-loaded micelles were pH-sensitive, as they turned on their imaging capability only in an acidic microenvironment. The micelle-targeting ability toward cancer cells was enhanced by conjugation with an antibody against the MUC1 protein. The ability of our antibody-decorated micelles to be switched on in acidic microenvironments and to target cancer cells expressing specific antigens, together with its high Gd(III) content and its small size (35-40 nm) reveals their potential use for early cancer detection by MRI.

  12. RAB-like 2 has an essential role in male fertility, sperm intra-flagellar transport, and tail assembly.

    Directory of Open Access Journals (Sweden)

    Jennifer C Y Lo

    Full Text Available A significant percentage of young men are infertile and, for the majority, the underlying cause remains unknown. Male infertility is, however, frequently associated with defective sperm motility, wherein the sperm tail is a modified flagella/cilia. Conversely, a greater understanding of essential mechanisms involved in tail formation may offer contraceptive opportunities, or more broadly, therapeutic strategies for global cilia defects. Here we have identified Rab-like 2 (RABL2 as an essential requirement for sperm tail assembly and function. RABL2 is a member of a poorly characterized clade of the RAS GTPase superfamily. RABL2 is highly enriched within developing male germ cells, where it localizes to the mid-piece of the sperm tail. Lesser amounts of Rabl2 mRNA were observed in other tissues containing motile cilia. Using a co-immunoprecipitation approach and RABL2 affinity columns followed by immunochemistry, we demonstrated that within developing haploid germ cells RABL2 interacts with intra-flagella transport (IFT proteins and delivers a specific set of effector (cargo proteins, including key members of the glycolytic pathway, to the sperm tail. RABL2 binding to effector proteins is regulated by GTP. Perturbed RABL2 function, as exemplified by the Mot mouse line that contains a mutation in a critical protein-protein interaction domain, results in male sterility characterized by reduced sperm output, and sperm with aberrant motility and short tails. Our data demonstrate a novel function for the RABL protein family, an essential role for RABL2 in male fertility and a previously uncharacterised mechanism for protein delivery to the flagellum.

  13. Measuring coseismic displacements with point-like targets offset tracking

    KAUST Repository

    Hu, Xie; Wang, Teng; Liao, Mingsheng

    2014-01-01

    Offset tracking is an important complement to measure large ground displacements in both azimuth and range dimensions where synthetic aperture radar (SAR) interferometry is unfeasible. Subpixel offsets can be obtained by searching for the cross-correlation peak calculated from the match patches uniformly distributed on two SAR images. However, it has its limitations, including redundant computation and incorrect estimations on decorrelated patches. In this letter, we propose a simple strategy that performs offset tracking on detected point-like targets (PT). We first detect image patches within bright PT by using a sinc-like template from a single SAR image and then perform offset tracking on them to obtain the pixel shifts. Compared with the standard method, the application on the 2010 M 7.2 El Mayor-Cucapah earthquake shows that the proposed PT offset tracking can significantly increase the cross-correlation and thus result in both efficiency and reliability improvements. © 2013 IEEE.

  14. Fabrication of a nanocarrier system through self-assembly of plasma protein and its tumor targeting

    International Nuclear Information System (INIS)

    Gong Guangming; Zhi Feng; Wang Kaikai; Tang Xiaolei; Yuan Ahu; Zhao Lili; Ding Dawei; Hu Yiqiao

    2011-01-01

    Human serum albumin (HSA) nanoparticles hold great promise as a nanocarrier system for targeted drug delivery. The objective of this study was to explore the possibility of preparing size controllable albumin nanoparticles using the disulfide bond breaking reagent β-mercaptoethanol (β-ME). The results showed that the protein concentration and temperature had positive effects on the sizes of the albumin nanoparticles, while pH had a negative effect on the rate of nanoparticle formation. The addition of β-ME induced changes in HSA secondary structure and exposed the hydrophobic core of HSA, leading to the formation of nanoparticles. Human serum albumin nanoparticles could be internalized by MCF-7 cells and mainly accumulated in cytoplasm. After injection in tumor bearing mice, the HSA nanoparticles accumulated in tumor tissues, demonstrating the targeting ability of the nanoparticles. Therefore, human serum albumin can be fabricated into nanoparticles by breaking the disulfide bonds and these nanoparticles exhibit high tumor targeting ability. Human serum albumin nanoparticles could be ideal for the targeted delivery of pharmacologically active substances.

  15. A Novel Strategy to Engineer Pre-Vascularized Full-Length Dental Pulp-like Tissue Constructs.

    Science.gov (United States)

    Athirasala, Avathamsa; Lins, Fernanda; Tahayeri, Anthony; Hinds, Monica; Smith, Anthony J; Sedgley, Christine; Ferracane, Jack; Bertassoni, Luiz E

    2017-06-12

    The requirement for immediate vascularization of engineered dental pulp poses a major hurdle towards successful implementation of pulp regeneration as an effective therapeutic strategy for root canal therapy, especially in adult teeth. Here, we demonstrate a novel strategy to engineer pre-vascularized, cell-laden hydrogel pulp-like tissue constructs in full-length root canals for dental pulp regeneration. We utilized gelatin methacryloyl (GelMA) hydrogels with tunable physical and mechanical properties to determine the microenvironmental conditions (microstructure, degradation, swelling and elastic modulus) that enhanced viability, spreading and proliferation of encapsulated odontoblast-like cells (OD21), and the formation of endothelial monolayers by endothelial colony forming cells (ECFCs). GelMA hydrogels with higher polymer concentration (15% w/v) and stiffness enhanced OD21 cell viability, spreading and proliferation, as well as endothelial cell spreading and monolayer formation. We then fabricated pre-vascularized, full-length, dental pulp-like tissue constructs by dispensing OD21 cell-laden GelMA hydrogel prepolymer in root canals of extracted teeth and fabricating 500 µm channels throughout the root canals. ECFCs seeded into the microchannels successfully formed monolayers and underwent angiogenic sprouting within 7 days in culture. In summary, the proposed approach is a simple and effective strategy for engineering of pre-vascularized dental pulp constructs offering potentially beneficial translational outcomes.

  16. Identification of Factors Promoting HBV Capsid Self-Assembly by Assembly-Promoting Antivirals.

    Science.gov (United States)

    Rath, Soumya Lipsa; Liu, Huihui; Okazaki, Susumu; Shinoda, Wataru

    2018-02-26

    Around 270 million individuals currently live with hepatitis B virus (HBV) infection. Heteroaryldihydropyrimidines (HAPs) are a family of antivirals that target the HBV capsid protein and induce aberrant self-assembly. The capsids formed resemble the native capsid structure but are unable to propagate the virus progeny because of a lack of RNA/DNA. Under normal conditions, self-assembly is initiated by the viral genome. The mode of action of HAPs, however, remains largely unknown. In this work, using molecular dynamics simulations, we attempted to understand the action of HAP by comparing the dynamics of capsid proteins with and without HAPs. We found that the inhibitor is more stable in higher oligomers. It retains its stability in the hexamer throughout 1 μs of simulation. Our results also show that the inhibitor might help in stabilizing the C-terminus, the HBc 149-183 arginine-rich domain of the capsid protein. The C-termini of dimers interact with each other, assisted by the HAP inhibitor. During capsid assembly, the termini are supposed to directly interact with the viral genome, thereby suggesting that the viral genome might work in a similar way to stabilize the capsid protein. Our results may help in understanding the underlying molecular mechanism of HBV capsid self-assembly, which should be crucial for exploring new drug targets and structure-based drug design.

  17. Sclerotic fibroma (storiform collagenoma)-like stroma in a fibroadenoma of axillary accessory breast tissue.

    Science.gov (United States)

    Val-Bernal, José Fernando; González-Vela, María Carmen; De Grado, Mauricio; Garijo, María Francisca

    2012-08-01

    Accessory breast tissue is a subcutaneous remnant persisting after normal embryological development of the breast. It occurs most frequently in the axilla. Fibroadenomas in axillary breast tissue are rare. We report the case of a 29-year-old female patient who presented a fibroadenoma arising in the accessory breast tissue of the right axillary fossa. The neoplasm showed foci of sclerotic fibroma-like stroma. The patient had no signs of Cowden's syndrome. To the best of our knowledge, a lesion of this kind has not been previously reported. This stromal change suggests an uncommon involutional phase of the fibroadenoma with production of sclerotic and hypocellular collagen. The lesion should be differentiated from extraneural perineuroma, from the changes in fibroadenomas in Cowden's syndrome, from sclerosing lobular hyperplasia (fibroadenomatoid mastopathy) and from pseudoangiomatous stromal hyperplasia. Copyright © 2012 John Wiley & Sons A/S.

  18. Research on Outfitting Virtual Assembly based on Ergonomics

    Directory of Open Access Journals (Sweden)

    Jiang Zuhua

    2018-01-01

    Full Text Available To improve the present situation where the assembly work of ship outfitting depends on manual experiential operation, the thesis, taking outfitting assembly operation as the research object and optimal assembly path as the target, puts forward the simulation method and procedure of outfitting virtual assembly considering operational posture, operational load, reachability and visibility and other ergonomic factors, taking pipe assembly operation of ship section as the application example. The results show that the method can obtain better assembly operation path, avoid interference of workers’ operation process and improve the efficiency of assembly operation.

  19. α-Fetoprotein promoter-driven Cre/LoxP-switched RNA interference for hepatocellular carcinoma tissue-specific target therapy.

    Directory of Open Access Journals (Sweden)

    Yuan-Fei Peng

    Full Text Available RNA interference (RNAi has recently emerged as a potential treatment modality for hepatocellular carcinoma (HCC therapy, but the lack of cellular targets and sustained efficacy limits its application. The purpose of this study is to develop an HCC tissue-specific RNAi system and investigate its possibility for HCC treatment.Two different HCC-specific RNAi systems in which therapeutic miRNA or shRNA against target gene (Beclin 1 was directly or indirectly driven by alpha-fetoprotein promoter (AFP-miRNA and AFP-Cre/LoxP-shRNA were constructed. Human HCC cell lines (HepG2, Hep3B and HCCLM3 and non-HCC cell lines (L-02, Hela and SW1116 were infected with the systems. The effectiveness and tissue-specificity of the systems were examined by Q-PCR and western blot analysis. The efficacy of the systems was further tested in mouse model of HCC by intravenous or intratumoral administration. The feasibility of the system for HCC treatment was evaluated by applying the system as adjuvant therapy to enhance sorafenib treatment. An AFP-Cre/LoxP-shRNA system targeting Atg5 gene (AFP-Cre/LoxP-shRNA-Atg5 was constructed and its efficacy in sensitizing HCC cells (MHCC97L/PLC to sorafenib treatment was examined by apoptosis assay in vitro and tumorigenesis assay in vivo.The AFP-miRNA system could silence target gene (Beclin 1 but required a high titer which was lethal to target cells. The AFP-Cre/LoxP-shRNA system could efficiently knockdown target gene while maintain high HCC specificity. Intratumoral injection of the AFP-Cre/LoxP-shRNA system could efficiently silence target gene (Beclin 1 in vivo while intravenous administration could not. The AFP-Cre/LoxP-shRNA system target Atg5 gene could significantly sensitize MHCC97L/PLC cells to sorafenib-induced apoptosis in vitro and tumor growth suppression in vivo.An efficient HCC tissue-specific RNAi system (AFP-Cre/LoxP-shRNA was successfully established. The system provides a usable tool for HCC-specific RNAi

  20. Truncated forms of viral VP2 proteins fused to EGFP assemble into fluorescent parvovirus-like particles

    Directory of Open Access Journals (Sweden)

    Vuento Matti

    2006-12-01

    Full Text Available Abstract Fluorescence correlation spectroscopy (FCS monitors random movements of fluorescent molecules in solution, giving information about the number and the size of for example nano-particles. The canine parvovirus VP2 structural protein as well as N-terminal deletion mutants of VP2 (-14, -23, and -40 amino acids were fused to the C-terminus of the enhanced green fluorescent protein (EGFP. The proteins were produced in insect cells, purified, and analyzed by western blotting, confocal and electron microscopy as well as FCS. The non-truncated form, EGFP-VP2, diffused with a hydrodynamic radius of 17 nm, whereas the fluorescent mutants truncated by 14, 23 and 40 amino acids showed hydrodynamic radii of 7, 20 and 14 nm, respectively. These results show that the non-truncated EGFP-VP2 fusion protein and the EGFP-VP2 constructs truncated by 23 and by as much as 40 amino acids were able to form virus-like particles (VLPs. The fluorescent VLP, harbouring VP2 truncated by 23 amino acids, showed a somewhat larger hydrodynamic radius compared to the non-truncated EGFP-VP2. In contrast, the construct containing EGFP-VP2 truncated by 14 amino acids was not able to assemble into VLP-resembling structures. Formation of capsid structures was confirmed by confocal and electron microscopy. The number of fluorescent fusion protein molecules present within the different VLPs was determined by FCS. In conclusion, FCS provides a novel strategy to analyze virus assembly and gives valuable structural information for strategic development of parvovirus-like particles.

  1. Toll-like receptors as targets for immune disorders.

    LENUS (Irish Health Repository)

    Keogh, Brian

    2012-02-01

    Since the identification of the first Toll-like receptor (TLR) in humans in 1997, understanding of the molecular basis for innate immunity has increased significantly. The TLR family and downstream signalling pathways have been extensively characterised, There is now significant evidence suggesting a role for TLRs in human inflammatory and immune diseases such as rheumatoid arthritis, diabetes, allergy\\/asthma and atherosclerosis. Various approaches have been taken to identify novel therapeutic agents targeting TLRs including biologics, small molecules and nucleic acid-based drugs. Several are now being evaluated in the clinic and showing promise against various diseases. This review paper outlines the recent advances in the understanding of TLR biology and highlights novel TLR agonists and antagonists in development for the treatment of immune diseases.

  2. Near infrared spectral polarization imaging of prostate cancer tissues using Cybesin: a receptor-targeted contrast agent

    Science.gov (United States)

    Pu, Yang; Wang, W. B.; Tang, G. C.; Liang, Kexian; Achilefu, S.; Alfano, R. R.

    2013-03-01

    Cybesin, a smart contrast agent to target cancer cells, was investigated using a near infrared (NIR) spectral polarization imaging technique for prostate cancer detection. The approach relies on applying a contrast agent that can target cancer cells. Cybesin, as a small ICG-derivative dye-peptide, emit fluorescence between 750 nm and 900 nm, which is in the "tissue optical window". Cybesin was reported targeting the over-expressed bombesin receptors in cancer cells in animal model and the human prostate cancers over-expressing bombesin receptors. The NIR spectral polarization imaging study reported here demonstrated that Cybesin can be used as a smart optical biomarker and as a prostate cancer receptor targeted contrast agent.

  3. Phenotypic high-throughput screening elucidates target pathway in breast cancer stem cell-like cells.

    Science.gov (United States)

    Carmody, Leigh C; Germain, Andrew R; VerPlank, Lynn; Nag, Partha P; Muñoz, Benito; Perez, Jose R; Palmer, Michelle A J

    2012-10-01

    Cancer stem cells (CSCs) are resistant to standard cancer treatments and are likely responsible for cancer recurrence, but few therapies target this subpopulation. Due to the difficulty in propagating CSCs outside of the tumor environment, previous work identified CSC-like cells by inducing human breast epithelial cells into an epithelial-to-mesenchymal transdifferentiated state (HMLE_sh_ECad). A phenotypic screen was conducted against HMLE_sh_ECad with 300 718 compounds from the Molecular Libraries Small Molecule Repository to identify selective inhibitors of CSC growth. The screen yielded 2244 hits that were evaluated for toxicity and selectivity toward an isogenic control cell line. An acyl hydrazone scaffold emerged as a potent and selective scaffold targeting HMLE_sh_ECad. Fifty-three analogues were acquired and tested; compounds ranged in potency from 790 nM to inactive against HMLE_sh_ECad. Of the analogues, ML239 was best-in-class with an IC(50)= 1.18 µM against HMLE_sh_ECad, demonstrated a >23-fold selectivity over the control line, and was toxic to another CSC-like line, HMLE_shTwist, and a breast carcinoma cell line, MDA-MB-231. Gene expression studies conducted with ML239-treated cells showed altered gene expression in the NF-κB pathway in the HMLE_sh_ECad line but not in the isogenic control line. Future studies will be directed toward the identification of ML239 target(s).

  4. Three-Dimensional Calcium Alginate Hydrogel Assembly via TiOPc-Based Light-Induced Controllable Electrodeposition

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2017-06-01

    Full Text Available Artificial reconstruction of three-dimensional (3D hydrogel microstructures would greatly contribute to tissue assembly in vitro, and has been widely applied in tissue engineering and drug screening. Recent technological advances in the assembly of functional hydrogel microstructures such as microfluidic, 3D bioprinting, and micromold-based 3D hydrogel fabrication methods have enabled the formation of 3D tissue constructs. However, they still lack flexibility and high efficiency, which restrict their application in 3D tissue constructs. Alternatively, we report a feasible method for the fabrication and reconstruction of customized 3D hydrogel blocks. Arbitrary hydrogel microstructures were fabricated in situ via flexible and rapid light-addressable electrodeposition. To demonstrate the versatility of this method, the higher-order assembly of 3D hydrogel blocks was investigated using a constant direct current (DC voltage (6 V applied between two electrodes for 20–120 s. In addition to the plane-based two-dimensional (2D assembly, hierarchical structures—including multi-layer 3D hydrogel structures and vessel-shaped structures—could be assembled using the proposed method. Overall, we developed a platform that enables researchers to construct complex 3D hydrogel microstructures efficiently and simply, which has the potential to facilitate research on drug screening and 3D tissue constructs.

  5. The Assembly of Cell-Encapsulating Microscale Hydrogels Using Acoustic Waves

    Science.gov (United States)

    Xu, Feng; Finley, Thomas Dylan; Turkaydin, Muge; Sung, Yuree; Gurkan, Umut Atakan; Yavuz, Ahmet Sinan; Guldiken, Rasim; Demirci, Utkan

    2011-01-01

    Microscale hydrogels find widespread applications in medicine and biology, e.g., as building blocks for tissue engineering and regenerative medicine. In these applications, these microgels are assembled to fabricate large complex 3D constructs. The success of this approach requires non-destructive and high throughput assembly of the microgels. Although various assembly methods have been developed based on modifying interfaces, and using microfluidics, so far, none of the available assembly technologies have shown the ability to assembly microgels using non-invasive fields rapidly within seconds in an efficient way. Acoustics has been widely used in biomedical area to manipulatedroplets, cells and biomolecules. In this study, we developed a simple, non-invasiveacoustic assembler for cell-encapsulating microgels with maintained cell viability (>93%). We assessed the assembler for both microbeads (with diameter of 50 µm and 100 µm) and microgels of different sizes and shapes (e.g., cubes, lock-and-key shapes, tetris, saw) in microdroplets (with volume of 10 µL, 20 µL, 40 µL, 80 µL). The microgels were assembled in second sin a non-invasive manner. These results indicate that the developed acoustic approach could become an enabling biotechnology tool for tissue engineering, regenerative medicine, pharmacology studies and high throughput screening applications. PMID:21820734

  6. Physics analyses of an accelerator-driven sub-critical assembly

    Science.gov (United States)

    Naberezhnev, Dmitry G.; Gohar, Yousry; Bailey, James; Belch, Henry

    2006-06-01

    Physics analyses have been performed for an accelerator-driven sub-critical assembly as a part of the Argonne National Laboratory activity in preparation for a joint conceptual design with the Kharkov Institute of Physics and Technology (KIPT) of Ukraine. KIPT has a plan to construct an accelerator-driven sub-critical assembly targeted towards the medical isotope production and the support of the Ukraine nuclear industry. The external neutron source is produced either through photonuclear reactions in tungsten or uranium targets, or deuteron reactions in a beryllium target. KIPT intends using the high-enriched uranium (HEU) for the fuel of the sub-critical assembly. The main objective of this paper is to study the possibility of utilizing low-enriched uranium (LEU) fuel instead of HEU fuel without penalizing the sub-critical assembly performance, in particular the neutron flux level. In the course of this activity, several studies have been carried out to investigate the main choices for the system's parameters. The external neutron source has been characterized and a pre-conceptual target design has been developed. Several sub-critical configurations with different fuel enrichments and densities have been considered. Based on our analysis, it was shown that the performance of the LEU fuel is comparable with that of the HEU fuel. The LEU fuel sub-critical assembly with 200-MeV electron energy and 100-kW electron beam power has an average total flux of ˜2.50×10 13 n/s cm 2 in the irradiation channels. The corresponding total facility power is ˜204 kW divided into 91 and 113 kW deposited in the target and sub-critical assemblies, respectively.

  7. Chemopreventive glucosinolate accumulation in various broccoli and collard tissues: Microfluidic-based targeted transcriptomics for by-product valorization.

    Science.gov (United States)

    Lee, Young-Sang; Ku, Kang-Mo; Becker, Talon M; Juvik, John A

    2017-01-01

    Floret, leaf, and root tissues were harvested from broccoli and collard cultivars and extracted to determine their glucosinolate and hydrolysis product profiles using high performance liquid chromatography and gas chromotography. Quinone reductase inducing bioactivity, an estimate of anti-cancer chemopreventive potential, of the extracts was measured using a hepa1c1c7 murine cell line. Extracts from root tissues were significantly different from other tissues and contained high levels of gluconasturtiin and glucoerucin. Targeted gene expression analysis on glucosinolate biosynthesis revealed that broccoli root tissue has elevated gene expression of AOP2 and low expression of FMOGS-OX homologs, essentially the opposite of what was observed in broccoli florets, which accumulated high levels of glucoraphanin. Broccoli floret tissue has significantly higher nitrile formation (%) and epithionitrile specifier protein gene expression than other tissues. This study provides basic information of the glucosinolate metabolome and transcriptome for various tissues of Brassica oleracea that maybe utilized as potential byproducts for the nutraceutical market.

  8. Layer-by-layer assembly of type I collagen and chondroitin sulfate on aminolyzed PU for potential cartilage tissue engineering application

    International Nuclear Information System (INIS)

    He Xianyun; Wang Yingjun; Wu Gang

    2012-01-01

    Highlights: ► A novel biodegradable polyurethane (PU) was successfully synthesized. ► Surface aminolyzing of the PU was performed by reacting it with 1,3-propanediamine. ► Collagen and chondroitin sulfate were deposited alternately on the PU surface. - Abstract: In this paper, a two-step method was used to synthesize a biodegradable polyurethane (PU) composed of L-lysine ethyl ester diisocyanate (LDI), poly(ε-caprolactone) diols (PCL-diol) and 1,4:3,6-dianhydro-D-sorbitol (isosorbide). Amino groups were introduced onto the surface of the PU membrane by an amination reacting with 1,3-propanediamine to produce polycationic substratum. And then, type I collagen (Col) and chondroitin sulfate (CS) were deposited alternately on the polycationic substratum through layer-by-layer (LBL) assembly technology. The FTIR and 1 H NMR results showed that the polyurethane was successfully synthesized. Rhodamine B isothiocyanate (RBITC) fluorescence spectrum indicated that amino groups were successfully introduced onto the PU surface. The results of quartz-crystal microbalance (QCM) and RBITC-Col fluorescence spectroscopy monitoring the LBL assemble process presented that the Col/CS deposited alternately on the PU surface. X-ray photoelectron spectroscopy (XPS) results displayed that the CS deposited on the PU surface as well. The surface of the assembled PU became even smoother observed from the surface morphology by atomic force microscopy (AFM) imaging. The hydrophilicity of the PU membrane was greatly enhanced though the modification of LBL assembly. The PU modified with the adsorption of Col/CS may be a potential application for cartilage tissue engineering due to its created mimicking chondrogenic environment.

  9. Formation of active inclusion bodies induced by hydrophobic self-assembling peptide GFIL8.

    Science.gov (United States)

    Wang, Xu; Zhou, Bihong; Hu, Weike; Zhao, Qing; Lin, Zhanglin

    2015-06-16

    In the last few decades, several groups have observed that proteins expressed as inclusion bodies (IBs) in bacteria could still be biologically active when terminally fused to an appropriate aggregation-prone partner such as pyruvate oxidase from Paenibacillus polymyxa (PoxB). More recently, we have demonstrated that three amphipathic self-assembling peptides, an alpha helical peptide 18A, a beta-strand peptide ELK16, and a surfactant-like peptide L6KD, have properties that induce target proteins into active IBs. We have developed an efficient protein expression and purification approach for these active IBs by introducing a self-cleavable intein molecule. In this study, the self-assembling peptide GFIL8 (GFILGFIL) with only hydrophobic residues was analyzed, and this peptide effectively induced the formation of cytoplasmic IBs in Escherichia coli when terminally attached to lipase A and amadoriase II. The protein aggregates in cells were confirmed by transmission electron microscopy analysis and retained ~50% of their specific activities relative to the native counterparts. We constructed an expression and separation coupled tag (ESCT) by incorporating an intein molecule, the Mxe GyrA intein. Soluble target proteins were successfully released from active IBs upon cleavage of the intein between the GFIL8 tag and the target protein, which was mediated by dithiothreitol. A variant of GFIL8, GFIL16 (GFILGFILGFILGFIL), improved the ESCT scheme by efficiently eliminating interference from the soluble intein-GFIL8 molecule. The yields of target proteins at the laboratory scale were 3.0-7.5 μg/mg wet cell pellet, which is comparable to the yields from similar ESCT constructs using 18A, ELK16, or the elastin-like peptide tag scheme. The all-hydrophobic self-assembling peptide GFIL8 induced the formation of active IBs in E. coli when terminally attached to target proteins. GFIL8 and its variant GFIL16 can act as a "pull-down" tag to produce purified soluble proteins with

  10. Single molecule sequencing-guided scaffolding and correction of draft assemblies.

    Science.gov (United States)

    Zhu, Shenglong; Chen, Danny Z; Emrich, Scott J

    2017-12-06

    Although single molecule sequencing is still improving, the lengths of the generated sequences are inevitably an advantage in genome assembly. Prior work that utilizes long reads to conduct genome assembly has mostly focused on correcting sequencing errors and improving contiguity of de novo assemblies. We propose a disassembling-reassembling approach for both correcting structural errors in the draft assembly and scaffolding a target assembly based on error-corrected single molecule sequences. To achieve this goal, we formulate a maximum alternating path cover problem. We prove that this problem is NP-hard, and solve it by a 2-approximation algorithm. Our experimental results show that our approach can improve the structural correctness of target assemblies in the cost of some contiguity, even with smaller amounts of long reads. In addition, our reassembling process can also serve as a competitive scaffolder relative to well-established assembly benchmarks.

  11. Modelling radiation fields of ion beams in tissue-like materials

    International Nuclear Information System (INIS)

    Burigo, Lucas Norberto

    2014-01-01

    Fast nuclei are ionizing radiation which can cause deleterious effects to irradiated cells. The modelling of the interactions of such ions with matter and the related effects are very important to physics, radiobiology, medicine and space science and technology. A powerful method to study the interactions of ionizing radiation with biological systems was developed in the field of microdosimetry. Microdosimetry spectra characterize the energy deposition to objects of cellular size, i.e., a few micrometers. In the present thesis the interaction of ions with tissue-like media was investigated using the Monte Carlo model for Heavy-Ion Therapy (MCHIT) developed at the Frankfurt Institute for Advanced Studies. MCHIT is a Geant4-based application intended to benchmark the physical models of Geant4 and investigate the physical properties of therapeutic ion beams. We have implemented new features in MCHIT in order to calculate microdosimetric quantities characterizing the radiation fields of accelerated nucleons and nuclei. The results of our Monte Carlo simulations were compared with recent experimental microdosimetry data. In addition to microdosimetry calculations with MCHIT, we also investigated the biological properties of ion beams, e.g. their relative biological effectiveness (RBE), by means of the modified Microdosimetric-Kinetic model (MKM). The MKM uses microdosimetry spectra in describing cell response to radiation. MCHIT+MKM allowed us to study the physical and biological properties of ion beams. The main results of the thesis are as follows: MCHIT is able to describe the spatial distribution of the physical dose in tissue-like media and microdosimetry spectra for ions with energies relevant to space research and ion-beam cancer therapy; MCHIT+MKM predicts a reduction of the biological effectiveness of ions propagating in extended medium due to nuclear fragmentation reactions; We predicted favourable biological dose-depth profiles for monoenergetic helium and

  12. Use of diagnostic dynamic contrast-enhanced (DCE)-MRI for targeting of soft tissue tumour biopsies at 3T: preliminary results

    Energy Technology Data Exchange (ETDEWEB)

    Noebauer-Huhmann, Iris-Melanie [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Neuroradiology and Musculoskeletal Radiology, Vienna (Austria); Medical University of Vienna, High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Medical University of Vienna/Vienna General Hospital, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Amann, Gabriele [Medical University of Vienna, Clinical Institute for Pathology, Vienna (Austria); Krssak, Martin [Medical University of Vienna, High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Medical University of Vienna, Department of Internal Medicine III, Endocrinology and Metabolism, Vienna (Austria); Panotopoulos, Joannis; Funovics, Philipp; Windhager, Reinhard [Medical University of Vienna, Department of Orthopaedics, Vienna (Austria); Szomolanyi, Pavol [Medical University of Vienna, High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Slovak Academy of Sciences, Department of Imaging Methods, Institute of Measurement Science, Bratislava (Slovakia); Weber, Michael; Czerny, Christian; Nemec, Stefan [Medical University of Vienna, Department of Biomedical Imaging and Image-guided Therapy, Division of Neuroradiology and Musculoskeletal Radiology, Vienna (Austria); Breitenseher, Martin [Landesklinikum Waldviertel Horn, Horn (Austria); Grabner, Guenther; Bogner, Wolfgang [Medical University of Vienna, High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Dominkus, Martin [Orthopaedics Hospital Speising, Vienna (Austria); Trattnig, Siegfried [Medical University of Vienna, High Field MR Center, Department of Biomedical Imaging and Image-guided Therapy, Vienna (Austria); Ludwig Boltzmann Institute for Experimental and Clinical Traumatology, Austrian Cluster for Tissue Regeneration, Vienna (Austria)

    2015-07-15

    To test the feasibility and accuracy of MR-guided soft tissue tumour biopsy at 3T, using the dynamic contrast-enhanced (DCE) information from staging MRI for intralesional targeting. After obtaining written informed consent for this institutional review board-approved study, 53 patients with suspected soft tissue tumours prospectively underwent preoperative staging MRI at 3T, including DCE, and subsequent MR-guided core needle biopsy. In 44/53 cases, DCE was heterogeneous and was used for intralesional biopsy targeting. Surgical, whole-specimen histology was used as the gold standard in 43/44 patients and revealed 42 soft tissue tumours (24 men; 18 women; mean age, 52 years; range, 19 - 84). Final surgical histology revealed eight benign lesions, six tumours of intermediate dignity, and 28 malignancies. All malignancies had shown heterogeneous DCE. The diagnostic yield of the biopsies was 100 % (42/42). Histological accuracy rates of biopsy were 100 % in predicting the dignity (42/42; 95 % CI [0.916 - 1.000]), 95.2 % for the tissue-specific entity (40/42; 95 % CI [0.847 - 0.987]), and 90.5 % for the tumour grade (38/42; 95 % CI [0.779 - 0.962]). Our preliminary study indicates that biopsy of soft tissue tumours can be performed accurately and safely with DCE targeted MR-guidance at 3T, using a combined staging/biopsy MRI protocol. (orig.)

  13. Use of diagnostic dynamic contrast-enhanced (DCE)-MRI for targeting of soft tissue tumour biopsies at 3T: preliminary results

    International Nuclear Information System (INIS)

    Noebauer-Huhmann, Iris-Melanie; Amann, Gabriele; Krssak, Martin; Panotopoulos, Joannis; Funovics, Philipp; Windhager, Reinhard; Szomolanyi, Pavol; Weber, Michael; Czerny, Christian; Nemec, Stefan; Breitenseher, Martin; Grabner, Guenther; Bogner, Wolfgang; Dominkus, Martin; Trattnig, Siegfried

    2015-01-01

    To test the feasibility and accuracy of MR-guided soft tissue tumour biopsy at 3T, using the dynamic contrast-enhanced (DCE) information from staging MRI for intralesional targeting. After obtaining written informed consent for this institutional review board-approved study, 53 patients with suspected soft tissue tumours prospectively underwent preoperative staging MRI at 3T, including DCE, and subsequent MR-guided core needle biopsy. In 44/53 cases, DCE was heterogeneous and was used for intralesional biopsy targeting. Surgical, whole-specimen histology was used as the gold standard in 43/44 patients and revealed 42 soft tissue tumours (24 men; 18 women; mean age, 52 years; range, 19 - 84). Final surgical histology revealed eight benign lesions, six tumours of intermediate dignity, and 28 malignancies. All malignancies had shown heterogeneous DCE. The diagnostic yield of the biopsies was 100 % (42/42). Histological accuracy rates of biopsy were 100 % in predicting the dignity (42/42; 95 % CI [0.916 - 1.000]), 95.2 % for the tissue-specific entity (40/42; 95 % CI [0.847 - 0.987]), and 90.5 % for the tumour grade (38/42; 95 % CI [0.779 - 0.962]). Our preliminary study indicates that biopsy of soft tissue tumours can be performed accurately and safely with DCE targeted MR-guidance at 3T, using a combined staging/biopsy MRI protocol. (orig.)

  14. Haplotype assembly in polyploid genomes and identical by descent shared tracts.

    Science.gov (United States)

    Aguiar, Derek; Istrail, Sorin

    2013-07-01

    Genome-wide haplotype reconstruction from sequence data, or haplotype assembly, is at the center of major challenges in molecular biology and life sciences. For complex eukaryotic organisms like humans, the genome is vast and the population samples are growing so rapidly that algorithms processing high-throughput sequencing data must scale favorably in terms of both accuracy and computational efficiency. Furthermore, current models and methodologies for haplotype assembly (i) do not consider individuals sharing haplotypes jointly, which reduces the size and accuracy of assembled haplotypes, and (ii) are unable to model genomes having more than two sets of homologous chromosomes (polyploidy). Polyploid organisms are increasingly becoming the target of many research groups interested in the genomics of disease, phylogenetics, botany and evolution but there is an absence of theory and methods for polyploid haplotype reconstruction. In this work, we present a number of results, extensions and generalizations of compass graphs and our HapCompass framework. We prove the theoretical complexity of two haplotype assembly optimizations, thereby motivating the use of heuristics. Furthermore, we present graph theory-based algorithms for the problem of haplotype assembly using our previously developed HapCompass framework for (i) novel implementations of haplotype assembly optimizations (minimum error correction), (ii) assembly of a pair of individuals sharing a haplotype tract identical by descent and (iii) assembly of polyploid genomes. We evaluate our methods on 1000 Genomes Project, Pacific Biosciences and simulated sequence data. HapCompass is available for download at http://www.brown.edu/Research/Istrail_Lab/. Supplementary data are available at Bioinformatics online.

  15. Molecular Therapeutic Targets for Glioma Angiogenesis

    Directory of Open Access Journals (Sweden)

    Shingo Takano

    2010-01-01

    Full Text Available Due to the prominent angiogenesis that occurs in malignant glioma, antiangiogenic therapy has been attempted. There have been several molecular targets that are specific to malignant gliomas, as well as more broadly in systemic cancers. In this review, I will focus on some topics related to molecular therapeutic targets for glioma angiogenesis. First, important angiogenic factors that could be considered molecular targets are VEGF, VEGF-induced proteins on endothelial cells, tissue factor, osteopontin, v3 integrin, and thymidine phosphorylase as well as endogenous inhibitors, soluble Flt1, and thrombospondin 1. Second, hypoxic areas are also decreased by metronomic CPT11 treatment as well as temozolomide. Third, glioma-derived endothelial cells that are genetically and functionally distinct from normal endothelial cells should be targeted, for example, with SDF-1 and CXCR7 chemokine. Fourth, endothelial progenitor cells (EPCs likely contribute towards glioma angiogenesis in the brain and could be useful as a drug delivery tool. Finally, blockade of delta-like 4 (Dll4 results in a nonfunctioning vasculature and could be another important target distinct from VEGF.

  16. Phase Transitions in the Nucleus: the functional implications of concentration-dependent assembly of a Liquid-like RNA/Protein Body

    Science.gov (United States)

    Zhu, Lian; Weber, Stephanie; Berry, Joel; Vaidya, Nilesh; Haataja, Mikko; Brangwynne, Clifford

    2015-03-01

    The nucleolus is a liquid-like membrane-less nuclear body which plays an important role in cell growth and size control. By modulating nucleolar component concentration through RNAi conditions that change C. elegans cell size, we find that nucleoli only assemble above a threshold concentration; moreover, the ripening dynamics of nucleated droplets are consistent with the hypothesis that the assembly of the nucleolus represents an intracellular liquid-liquid phase transition. A key question is how this phase-transition is linked to the primary function of the nucleolus, in transcribing and processing ribosomal RNA. To address this, we characterize the localization of RNA Polymerase I, a key transcriptional enzyme, into nucleolar foci as a function of nucleolar component concentration. Our results suggest that there are a small number of key disordered phosphoproteins that may serve as a link between transcription and assembly. Finally, we present preliminary results using a reduced model system consisting of purified nucleolar proteins to assess the ability of nucleolar proteins to drive liquid-liquid phase separation in vitro. These results lay the foundation for a quantitative understanding of intracellular phase transitions and their impact on biomedically-critical RNA-processing steps.

  17. Efficient surface enhanced Raman scattering on confeito-like gold nanoparticle-adsorbed self-assembled monolayers.

    Science.gov (United States)

    Chang, Chia-Chi; Imae, Toyoko; Chen, Liang-Yih; Ujihara, Masaki

    2015-12-28

    Confeito-like gold nanoparticles (AuNPs; average diameter = 80 nm) exhibiting a plasmon absorption band at 590 nm were adsorbed through immersion-adsorption on two self-assembled monolayers (SAMs) of 3-aminopropyltriethoxysilane (APTES-SAM) and polystyrene spheres coated with amine-terminated poly(amido amine) dendrimers (DEN/PS-SAM). The surface enhanced Raman scattering (SERS) effect on the SAM substrates was examined using the molecules of a probe dye, rhodamine 6G (R6G). The Raman scattering was strongly intensified on both substrates, but the enhancement factor (>10,000) of the AuNP/DEN/PS-SAM hierarchy substrate was 5-10 times higher than that of the AuNP/APTES-SAM substrate. This strong enhancement is attributed to the large surface area of the substrate and the presence of hot spots. Furthermore, analyzing the R6G concentration dependence of SERS suggested that the enhancement mechanism effectively excited the R6G molecules in the first layer on the hot spots and invoked the strong SERS effect. These results indicate that the SERS activity of confeito-like AuNPs on SAM substrates has high potential in molecular electronic devices and ultrasensitive analyses.

  18. The Amaranth Genome: Genome, Transcriptome, and Physical Map Assembly

    Directory of Open Access Journals (Sweden)

    J. W. Clouse

    2016-03-01

    Full Text Available Amaranth ( L. is an emerging pseudocereal native to the New World that has garnered increased attention in recent years because of its nutritional quality, in particular its seed protein and more specifically its high levels of the essential amino acid lysine. It belongs to the Amaranthaceae family, is an ancient paleopolyploid that shows disomic inheritance (2 = 32, and has an estimated genome size of 466 Mb. Here we present a high-quality draft genome sequence of the grain amaranth. The genome assembly consisted of 377 Mb in 3518 scaffolds with an N of 371 kb. Repetitive element analysis predicted that 48% of the genome is comprised of repeat sequences, of which -like elements were the most commonly classified retrotransposon. A de novo transcriptome consisting of 66,370 contigs was assembled from eight different amaranth tissue and abiotic stress libraries. Annotation of the genome identified 23,059 protein-coding genes. Seven grain amaranths (, , and and their putative progenitor ( were resequenced. A single nucleotide polymorphism (SNP phylogeny supported the classification of as the progenitor species of the grain amaranths. Lastly, we generated a de novo physical map for using the BioNano Genomics’ Genome Mapping platform. The physical map spanned 340 Mb and a hybrid assembly using the BioNano physical maps nearly doubled the N of the assembly to 697 kb. Moreover, we analyzed synteny between amaranth and sugar beet ( L. and estimated, using analysis, the age of the most recent polyploidization event in amaranth.

  19. Effect of graphite target power density on tribological properties of graphite-like carbon films

    Science.gov (United States)

    Dong, Dan; Jiang, Bailing; Li, Hongtao; Du, Yuzhou; Yang, Chao

    2018-05-01

    In order to improve the tribological performance, a series of graphite-like carbon (GLC) films with different graphite target power densities were prepared by magnetron sputtering. The valence bond and microstructure of films were characterized by AFM, TEM, XPS and Raman spectra. The variation of mechanical and tribological properties with graphite target power density was analyzed. The results showed that with the increase of graphite target power density, the deposition rate and the ratio of sp2 bond increased obviously. The hardness firstly increased and then decreased with the increase of graphite target power density, whilst the friction coefficient and the specific wear rate increased slightly after a decrease with the increasing graphite target power density. The friction coefficient and the specific wear rate were the lowest when the graphite target power density was 23.3 W/cm2.

  20. Decay patterns of target-like and projectile-like nuclei in 84Kr+197Au, natU reactions at E/A=150 MeV

    International Nuclear Information System (INIS)

    Quednau, B.M.; Galin, J.; Ledoux, X.; Crema, E.; Gebauer, B.; Hilscher, D.; Jahnke, U.; Jacquet, D.; Leray, S.; and others.

    1996-01-01

    The reactions 84 Kr+ 197 Au and 84 Kr+ nat U were studied at E/A=150 MeV employing the large-volume neutron multiplicity filter ORION at SATURNE. The observed correlations between the atomic number of projectile-like nuclei and neutron multiplicity indicate large excitation energies in the primary projectile- and target-like fragments. Angular correlations between the fission fragments of the U-like nucleus and the projectile-like fragments show a memory of the reaction plane, however no indications of spin effects are found. (author)

  1. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Anthony, A.J.

    1980-01-01

    A bimetallic spacer means is cooperatively associated with a nuclear fuel assembly and operative to resist the occurrence of in-reactor bowing of the nuclear fuel assembly. The bimetallic spacer means in one embodiment of the invention includes a space grid formed, at least principally, of zircaloy to the external surface of which are attached a plurality of stainless steel strips. In another embodiment the strips are attached to fuel pins. In each of the embodiments, the stainless steel strips during power production expand outwardly to a greater extent than do the members to which the stainless steel strips are attached, thereby forming stiff springs which abut against like bimetallic spacer means with which the other nuclear fuel assemblies are provided in a given nuclear reactor core to thus prevent the occurrence of in-reactor bowing of the nuclear fuel assemblies. (author)

  2. Bioconjugation of recombinant tissue plasminogen activator to magnetic nanocarriers for targeted thrombolysis

    Directory of Open Access Journals (Sweden)

    Yang HW

    2012-10-01

    Full Text Available Hung-Wei Yang,1,* Mu-Yi Hua,1,* Kun-Ju Lin,2,* Shiaw-Pyng Wey,3 Rung-Ywan Tsai,4 Siao-Yun Wu,5 Yi-Ching Lu,5 Hao-Li Liu,6 Tony Wu,7 Yunn-Hwa Ma5 1Chang Gung Molecular Medicine Research Center, Department of Chemical and Materials Engineering, 2Molecular Imaging Center, Department of Nuclear Medicine, Chang Gung Memorial Hospital, Kuei-Shan, Tao-Yuan, Taiwan, Republic of China; 3Department of Medical Imaging and Radiological Sciences, 4Electronics and Optoelectronics Research Laboratories, Industrial Technology Research Institute, Hsin-chu, Taiwan, Republic of China; 5Department of Physiology and Pharmacology and Healthy Aging Research Center, 6Department of Electrical Engineering, Chang Gung University, Kuei-Shan, Tao-Yuan, Taiwan, Republic of China; 7Department of Neurology, Chang Gung University College of Medicine and Memorial Hospital, Tao-Yuan, Taiwan, Republic of China*These authors contributed equally to this workAbstract: Low-toxicity magnetic nanocarriers (MNCs composed of a shell of poly [aniline-co-N-(1-one-butyric acid aniline] over a Fe3O4 magnetic nanoparticle core were developed to carry recombinant tissue plasminogen activator (rtPA in MNC-rtPA for targeted thrombolysis. With an average diameter of 14.8 nm, the MNCs exerted superparamagnetic properties. Up to 276 µg of active rtPA was immobilized per mg of MNCs, and the stability of the immobilized rtPA was greatly improved during storage at 4°C and 25°C. In vitro thrombolysis testing with a tubing system demonstrated that magnet-guided MNC-rtPA showed significantly improved thrombolysis compared with free rtPA and reduced the clot lysis time from 39.2 ± 3.2 minutes to 10.8 ± 4.2 minutes. In addition, magnet-guided MNC-rtPA at 20% of the regular rtPA dose restored blood flow within 15–25 minutes of treatment in a rat embolism model without triggering hematological toxicity. In conclusion, this improved system is based on magnetic targeting accelerated thrombolysis and is

  3. Neutron emission from projectile-like and target-like fragments in the 18O+48Ti reaction at E(18O)=116 MeV

    International Nuclear Information System (INIS)

    Chambon, B.; Drain, D.; Pastor, C.; Dauchy, A.; Giorni, A.; Morand, C.

    1982-07-01

    Angular correlations between neutrons and projectile-like fragments detected near the grazing angle were analysed by assuming two incoherent neutrons sources. One source describes slower neutrons evaporated by target-like fragments in equilibrium. The faster, forward-peaked neutrons originate from a second source strongly correlated with the projectile-like fragments with regards to velocity and direction. In some cases neutron emission may even be attributed to known neutron emitter levels in excited ejectiles

  4. Canine parvovirus-like particles, a novel nanomaterial for tumor targeting

    Directory of Open Access Journals (Sweden)

    Destito Giuseppe

    2006-02-01

    Full Text Available Abstract Specific targeting of tumor cells is an important goal for the design of nanotherapeutics for the treatment of cancer. Recently, viruses have been explored as nano-containers for specific targeting applications, however these systems typically require modification of the virus surface using chemical or genetic means to achieve tumor-specific delivery. Interestingly, there exists a subset of viruses with natural affinity for receptors on tumor cells that could be exploited for nanotechnology applications. For example, the canine parvovirus (CPV utilizes transferrin receptors (TfRs for binding and cell entry into canine as well as human cells. TfRs are over-expressed by a variety of tumor cells and are widely being investigated for tumor-targeted drug delivery. We explored whether the natural tropism of CPV to TfRs could be harnessed for targeting tumor cells. Towards this goal, CPV virus-like particles (VLPs produced by expression of the CPV-VP2 capsid protein in a baculovirus expression system were examined for attachment of small molecules and delivery to tumor cells. Structural modeling suggested that six lysines per VP2 subunit are presumably addressable for bioconjugation on the CPV capsid exterior. Between 45 and 100 of the possible 360 lysines/particle could be routinely derivatized with dye molecules depending on the conjugation conditions. Dye conjugation also demonstrated that the CPV-VLPs could withstand conditions for chemical modification on lysines. Attachment of fluorescent dyes neither impaired binding to the TfRs nor affected internalization of the 26 nm-sized VLPs into several human tumor cell lines. CPV-VLPs therefore exhibit highly favorable characteristics for development as a novel nanomaterial for tumor targeting.

  5. Myo/Nog cells: targets for preventing the accumulation of skeletal muscle-like cells in the human lens.

    Directory of Open Access Journals (Sweden)

    Jacquelyn Gerhart

    Full Text Available Posterior capsule opacification (PCO is a vision impairing condition that arises in some patients following cataract surgery. The fibrotic form of PCO is caused by myofibroblasts that may emerge in the lens years after surgery. In the chick embryo lens, myofibroblasts are derived from Myo/Nog cells that are identified by their expression of the skeletal muscle specific transcription factor MyoD, the bone morphogenetic protein inhibitor Noggin, and the epitope recognized by the G8 monoclonal antibody. The goal of this study was to test the hypothesis that depletion of Myo/Nog cells will prevent the accumulation of myofibroblasts in human lens tissue. Myo/Nog cells were present in anterior, equatorial and bow regions of the human lens, cornea and ciliary processes. In anterior lens tissue removed by capsulorhexis, Myo/Nog cells had synthesized myofibroblast and skeletal muscle proteins, including vimentin, MyoD and sarcomeric myosin. Alpha smooth muscle actin (α-SMA was detected in a subpopulation of Myo/Nog cells. Areas of the capsule denuded of epithelial cells were surrounded by Myo/Nog cells. Some of these cell free areas contained a wrinkle in the capsule. Depletion of Myo/Nog cells eliminated cells expressing skeletal muscle proteins in 5-day cultures but did not affect cells immunoreactive for beaded filament proteins that accumulate in differentiating lens epithelial cells. Transforming growth factor-betas 1 and 2 that mediate an epithelial-mesenchymal transition, did not induce the expression of skeletal muscle proteins in lens cells following Myo/Nog cell depletion. This study demonstrates that Myo/Nog cells in anterior lens tissue removed from cataract patients have undergone a partial differentiation to skeletal muscle. Myo/Nog cells appear to be the source of skeletal muscle-like cells in explants of human lens tissue. Targeting Myo/Nog cells with the G8 antibody during cataract surgery may reduce the incidence of PCO.

  6. Characterization of self-assembled virus-like particles of dromedary camel hepatitis e virus generated by recombinant baculoviruses.

    Science.gov (United States)

    Zhou, Xianfeng; Kataoka, Michiyo; Liu, Zheng; Takeda, Naokazu; Wakita, Takaji; Li, Tian-Cheng

    2015-12-02

    Dromedary camel hepatitis E virus (DcHEV), a novel hepatitis E virus, has been identified in dromedary camels in Dubai, United Arab Emirates. The antigenicity, pathogenicity and epidemiology of this virus have been unclear. Here we first used a recombinant baculovirus expression system to express the 13 and 111 N-terminus amino-acid-truncated DcHEV ORF2 protein in insect Tn5 cells, and we obtained two types of virus-like particles (VLPs) with densities of 1.300 g/cm(3) and 1.285 g/cm(3), respectively. The small VLPs (Dc4sVLPs) were estimated to be 24 nm in diameter, and were assembled by a protein with the molecular mass 53 kDa. The large VLPs (Dc3nVLPs and Dc4nVLPs) were 35 nm in diameter, and were assembled by a 64-kDa protein. An antigenic analysis demonstrated that DcHEV was cross-reactive with G1, G3-G6, ferret and rat HEVs, and DcHEV showed a stronger cross-reactivity to G1 G3-G6 HEV than it did to rat and ferret HEV. In addition, the antibody against DcHEV-LPs neutralized G1 and G3 HEV in a cell culture system, suggesting that the serotypes of these HEVs are identical. We also found that the amino acid residue Met-358 affects the small DcHEV-LPs assembly. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Molecular-Targeted Immunotherapeutic Strategy for Melanoma via Dual-Targeting Nanoparticles Delivering Small Interfering RNA to Tumor-Associated Macrophages.

    Science.gov (United States)

    Qian, Yuan; Qiao, Sha; Dai, Yanfeng; Xu, Guoqiang; Dai, Bolei; Lu, Lisen; Yu, Xiang; Luo, Qingming; Zhang, Zhihong

    2017-09-26

    Tumor-associated macrophages (TAMs) are a promising therapeutic target for cancer immunotherapy. Targeted delivery of therapeutic drugs to the tumor-promoting M2-like TAMs is challenging. Here, we developed M2-like TAM dual-targeting nanoparticles (M2NPs), whose structure and function were controlled by α-peptide (a scavenger receptor B type 1 (SR-B1) targeting peptide) linked with M2pep (an M2 macrophage binding peptide). By loading anti-colony stimulating factor-1 receptor (anti-CSF-1R) small interfering RNA (siRNA) on the M2NPs, we developed a molecular-targeted immunotherapeutic approach to specifically block the survival signal of M2-like TAMs and deplete them from melanoma tumors. We confirmed the validity of SR-B1 for M2-like TAM targeting and demonstrated the synergistic effect of the two targeting units (α-peptide and M2pep) in the fusion peptide (α-M2pep). After being administered to tumor-bearing mice, M2NPs had higher affinity to M2-like TAMs than to tissue-resident macrophages in liver, spleen, and lung. Compared with control treatment groups, M2NP-based siRNA delivery resulted in a dramatic elimination of M2-like TAMs (52%), decreased tumor size (87%), and prolonged survival. Additionally, this molecular-targeted strategy inhibited immunosuppressive IL-10 and TGF-β production and increased immunostimulatory cytokines (IL-12 and IFN-γ) expression and CD8 + T cell infiltration (2.9-fold) in the tumor microenvironment. Moreover, the siRNA-carrying M2NPs down-regulated expression of the exhaustion markers (PD-1 and Tim-3) on the infiltrating CD8 + T cells and stimulated their IFN-γ secretion (6.2-fold), indicating the restoration of T cell immune function. Thus, the dual-targeting property of M2NPs combined with RNA interference provides a potential strategy of molecular-targeted cancer immunotherapy for clinical application.

  8. Suitability of Different Natural and Synthetic Biomaterials for Dental Pulp Tissue Engineering.

    Science.gov (United States)

    Galler, Kerstin M; Brandl, Ferdinand P; Kirchhof, Susanne; Widbiller, Matthias; Eidt, Andreas; Buchalla, Wolfgang; Göpferich, Achim; Schmalz, Gottfried

    2018-02-01

    Dental pulp tissue engineering is possible after insertion of pulpal stem cells combined with a scaffold into empty root canals. Commonly used biomaterials are collagen or poly(lactic) acid, which are either difficult to modify or to insert into such a narrow space. New hydrogel scaffolds with bioactive, specifically tailored functions could optimize the conditions for this approach. Different synthetic and natural hydrogels were tested for their suitability to engineer dental pulp. Two functionalized modifications of polyethylene glycol were developed in this study and compared to a self-assembling peptide, as well as to collagen and fibrin. Cell viability of dental pulp stem cells in test materials was assessed over two weeks. Cells in selected test materials laden with dentin-derived growth factors were inserted into human tooth roots and implanted subcutaneously into immunocompromised mice. In vitro cell culture exhibited distinct differences between scaffold types, where viability was significantly higher in natural compared to synthetic materials. In vivo experiments showed considerable differences regarding scaffold degradation, soft tissue formation, vascularization, and odontoblast-like cell differentiation. Fibrin appeared most suitable to enable generation of a pulp-like tissue and differentiation of cells into odontoblasts at the cell-dentin interface. In conclusion, natural materials, especially fibrin, proved to be superior compared to synthetic scaffolds regarding cell viability and dental pulp-like tissue formation.

  9. Nuclear fuel assembly

    International Nuclear Information System (INIS)

    Hayashi, Hiroshi; Watari, Yoshio; Hizahara, Hiroshi; Masuoka, Ryuzo.

    1970-01-01

    When exchanging nuclear fuel assemblies during the operation of a nuclear reactor, melting of fuel bodies, and severence of tubular claddings is halted at the time of insertion by furnishing a neutron absorbing material such as B 10 , Cd, Gd or the like at the forward end of the fuel assembly to thereby lower the power peak at the forward ends of the fuel elements to within tolerable levels and thus prevent both fuel liquification and excessive expansion. The neutron absorbing material may be attached in the form of a plate to the fuel assembly forward tie plate, or may be inserted as a pellet into the front end of the tubular cladding. (Owens, K.J.)

  10. Inhibition of tumor angiogenesis and tumor growth by the DSL domain of human Delta-like 1 targeted to vascular endothelial cells.

    Science.gov (United States)

    Zhao, Xing-Cheng; Dou, Guo-Rui; Wang, Li; Liang, Liang; Tian, Deng-Mei; Cao, Xiu-Li; Qin, Hong-Yan; Wang, Chun-Mei; Zhang, Ping; Han, Hua

    2013-07-01

    The growth of solid tumors depends on neovascularization. Several therapies targeting tumor angiogenesis have been developed. However, poor response in some tumors and emerging resistance necessitate further investigations of new drug targets. Notch signal pathway plays a pivotal role in vascular development and tumor angiogenesis. Either blockade or forced activation of this pathway can inhibit angiogenesis. As blocking Notch pathway results in the formation of vascular neoplasm, activation of Notch pathway to prevent tumor angiogenesis might be an alternative choice. However, an in vivo deliverable reagent with highly efficient Notch-activating capacity has not been developed. Here, we generated a polypeptide, hD1R, which consists of the Delta-Serrate-Lag-2 fragment of the human Notch ligand Delta-like 1 and an arginine-glycine-aspartate (RGD) motif targeting endothelial cells (ECs). We showed that hD1R could bind to ECs specifically through its RGD motif and effectively triggered Notch signaling in ECs. We demonstrated both in vitro and in vivo that hD1R inhibited angiogenic sprouting and EC proliferation. In tumor-bearing mice, the injection of hD1R effectively repressed tumor growth, most likely through increasing tumor hypoxia and tissue necrosis. The amount and width of vessels reduced remarkably in tumors of mice treated with hD1R. Moreover, vessels in tumors of mice treated with hD1R recruited more NG2(+) perivascular cells and were better perfused. Combined application of hD1R and chemotherapy with cisplatin and teniposide revealed that these two treatments had additive antitumor effects. Our study provided a new strategy for antiangiogenic tumor therapy.

  11. Inhibition of Tumor Angiogenesis and Tumor Growth by the DSL Domain of Human Delta-Like 1 Targeted to Vascular Endothelial Cells

    Directory of Open Access Journals (Sweden)

    Xing-Cheng Zhao

    2013-07-01

    Full Text Available The growth of solid tumors depends on neovascularization. Several therapies targeting tumor angiogenesis have been developed. However, poor response in some tumors and emerging resistance necessitate further investigations of newdrug targets. Notch signal pathway plays a pivotal role in vascular development and tumor angiogenesis. Either blockade or forced activation of this pathway can inhibit angiogenesis. As blocking Notch pathway results in the formation of vascular neoplasm, activation of Notch pathway to prevent tumor angiogenesis might be an alternative choice. However, an in vivo deliverable reagent with highly efficient Notch-activating capacity has not been developed. Here, we generated a polypeptide, hD1R, which consists of the Delta-Serrate-Lag-2 fragment of the human Notch ligand Delta-like 1 and an arginine-glycine-aspartate (RGD motif targeting endothelial cells (ECs. We showed that hD1R could bind to ECs specifically through its RGD motif and effectively triggered Notch signaling in ECs. We demonstrated both in vitro and in vivo that hD1R inhibited angiogenic sprouting and EC proliferation. In tumor-bearing mice, the injection of hD1R effectively repressed tumor growth, most likely through increasing tumor hypoxia and tissue necrosis. The amount and width of vessels reduced remarkably in tumors of mice treated with hD1R. Moreover, vessels in tumors of mice treated with hD1R recruited more NG2+ perivascular cells and were better perfused. Combined application of hD1R and chemotherapy with cisplatin and teniposide revealed that these two treatments had additive antitumor effects. Our study provided a new strategy for antiangiogenic tumor therapy.

  12. Deep-Dive Targeted Quantification for Ultrasensitive Analysis of Proteins in Nondepleted Human Blood Plasma/Serum and Tissues

    Energy Technology Data Exchange (ETDEWEB)

    Nie, Song [Biological Sciences Division; Shi, Tujin [Biological Sciences Division; Fillmore, Thomas L. [Biological Sciences Division; Schepmoes, Athena A. [Biological Sciences Division; Brewer, Heather [Biological Sciences Division; Gao, Yuqian [Biological Sciences Division; Song, Ehwang [Biological Sciences Division; Wang, Hui [Biological Sciences Division; Rodland, Karin D. [Biological Sciences Division; Qian, Wei-Jun [Biological Sciences Division; Smith, Richard D. [Biological Sciences Division; Liu, Tao [Biological Sciences Division

    2017-08-11

    Mass spectrometry-based targeted proteomics (e.g., selected reaction monitoring, SRM) is emerging as an attractive alternative to immunoassays for protein quantification. Recently we have made significant progress in SRM sensitivity for enabling quantification of low ng/mL to sub-ng/mL level proteins in nondepleted human blood plasma/serum without affinity enrichment. However, precise quantification of extremely low abundant but biologically important proteins (e.g., ≤100 pg/mL in blood plasma/serum) using targeted proteomics approaches still remains challenging. To address this need, we have developed an antibody-independent Deep-Dive SRM (DD-SRM) approach that capitalizes on multidimensional high-resolution reversed-phase liquid chromatography (LC) separation for target peptide enrichment combined with precise selection of target peptide fractions of interest, significantly improving SRM sensitivity by ~5 orders of magnitude when compared to conventional LC-SRM. Application of DD-SRM to human serum and tissue has been demonstrated to enable precise quantification of endogenous proteins at ~10 pg/mL level in nondepleted serum and at <10 copies per cell level in tissue. Thus, DD-SRM holds great promise for precisely measuring extremely low abundance proteins or protein modifications, especially when high-quality antibody is not available.

  13. Targeted deletion of fibrinogen like protein 1 reveals a novel role in energy substrate utilization.

    Directory of Open Access Journals (Sweden)

    Valeriy Demchev

    Full Text Available Fibrinogen like protein 1(Fgl1 is a secreted protein with mitogenic activity on primary hepatocytes. Fgl1 is expressed in the liver and its expression is enhanced following acute liver injury. In animals with acute liver failure, administration of recombinant Fgl1 results in decreased mortality supporting the notion that Fgl1 stimulates hepatocyte proliferation and/or protects hepatocytes from injury. However, because Fgl1 is secreted and detected in the plasma, it is possible that the role of Fgl1 extends far beyond its effect on hepatocytes. In this study, we show that Fgl1 is additionally expressed in brown adipose tissue. We find that signals elaborated following liver injury also enhance the expression of Fgl1 in brown adipose tissue suggesting that there is a cross talk between the injured liver and adipose tissues. To identify extra hepatic effects, we generated Fgl1 deficient mice. These mice exhibit a phenotype suggestive of a global metabolic defect: Fgl1 null mice are heavier than wild type mates, have abnormal plasma lipid profiles, fasting hyperglycemia with enhanced gluconeogenesis and exhibit differences in white and brown adipose tissue morphology when compared to wild types. Because Fgl1 shares structural similarity to Angiopoietin like factors 2, 3, 4 and 6 which regulate lipid metabolism and energy utilization, we postulate that Fgl1 is a member of an emerging group of proteins with key roles in metabolism and liver regeneration.

  14. Characterization of the omega-conotoxin target. Evidence for tissue-specific heterogeneity in calcium channel types

    International Nuclear Information System (INIS)

    Cruz, L.J.; Johnson, D.S.; Olivera, B.M.

    1987-01-01

    Omega-Conotoxin GVIA (omega-CgTx-VIA) is a 27 amino acid peptide from the venom of the fish-hunting snail, Conus geographus, that blocks voltage-activated Ca channels. The characterization of a biologically active, homogeneous 125 I-labeled monoiodinated Tyr 22 derivative of omega-conotoxin GVIA and its use in binding and cross-linking studies are described. The 125 I-labeled toxin is specifically cross-linked to a receptor protein with an apparent M/sub r/ of 135,000. The stoichiometry between omega-conotoxin and nitrendipine binding sites in different chick tissues was determined. Skeletal muscle has a high concentration of [ 3 H]nitrendipine binding sites but no detectable omega-conotoxin sites. Brain microsomes have both binding sites, but omega-conotoxin targets are in excess. These results, combined with recent electrophysiological studies define four types of Ca channels in chick tissues, N, T, L/sub n/ (omega sensitive), and L/sub m/ (omega insensitive), and are consistent with the hypothesis that the α-subunits of certain neuronal Ca 2+ channels (L/sub n/, N) are the molecular targets of omega-conotoxin GVIA

  15. Layer-by-layer assembly of type I collagen and chondroitin sulfate on aminolyzed PU for potential cartilage tissue engineering application

    Energy Technology Data Exchange (ETDEWEB)

    He Xianyun [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China); Wang Yingjun, E-mail: imwangyj@163.com [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China) and National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China) and Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China); Wu Gang, E-mail: imwugang@scut.edu.cn [School of Materials Science and Engineering, South China University of Technology, Guangzhou 510641 (China); National Engineering Research Center for Tissue Restoration and Reconstruction, Guangzhou 510006 (China); Guangdong Province Key Laboratory of Biomedical Engineering, South China University of Technology, Guangzhou 510006 (China)

    2012-10-01

    Highlights: Black-Right-Pointing-Pointer A novel biodegradable polyurethane (PU) was successfully synthesized. Black-Right-Pointing-Pointer Surface aminolyzing of the PU was performed by reacting it with 1,3-propanediamine. Black-Right-Pointing-Pointer Collagen and chondroitin sulfate were deposited alternately on the PU surface. - Abstract: In this paper, a two-step method was used to synthesize a biodegradable polyurethane (PU) composed of L-lysine ethyl ester diisocyanate (LDI), poly({epsilon}-caprolactone) diols (PCL-diol) and 1,4:3,6-dianhydro-D-sorbitol (isosorbide). Amino groups were introduced onto the surface of the PU membrane by an amination reacting with 1,3-propanediamine to produce polycationic substratum. And then, type I collagen (Col) and chondroitin sulfate (CS) were deposited alternately on the polycationic substratum through layer-by-layer (LBL) assembly technology. The FTIR and {sup 1}H NMR results showed that the polyurethane was successfully synthesized. Rhodamine B isothiocyanate (RBITC) fluorescence spectrum indicated that amino groups were successfully introduced onto the PU surface. The results of quartz-crystal microbalance (QCM) and RBITC-Col fluorescence spectroscopy monitoring the LBL assemble process presented that the Col/CS deposited alternately on the PU surface. X-ray photoelectron spectroscopy (XPS) results displayed that the CS deposited on the PU surface as well. The surface of the assembled PU became even smoother observed from the surface morphology by atomic force microscopy (AFM) imaging. The hydrophilicity of the PU membrane was greatly enhanced though the modification of LBL assembly. The PU modified with the adsorption of Col/CS may be a potential application for cartilage tissue engineering due to its created mimicking chondrogenic environment.

  16. Peripheral CLOCK Regulates Target-Tissue Glucocorticoid Receptor Transcriptional Activity in a Circadian Fashion in Man

    Science.gov (United States)

    Charmandari, Evangelia; Chrousos, George P.; Lambrou, George I.; Pavlaki, Aikaterini; Koide, Hisashi; Ng, Sinnie Sin Man; Kino, Tomoshige

    2011-01-01

    Context and Objective Circulating cortisol fluctuates diurnally under the control of the “master” circadian CLOCK, while the peripheral “slave” counterpart of the latter regulates the transcriptional activity of the glucocorticoid receptor (GR) at local glucocorticoid target tissues through acetylation. In this manuscript, we studied the effect of CLOCK-mediated GR acetylation on the sensitivity of peripheral tissues to glucocorticoids in humans. Design and Participants We examined GR acetylation and mRNA expression of GR, CLOCK-related and glucocorticoid-responsive genes in peripheral blood mononuclear cells (PBMCs) obtained at 8 am and 8 pm from 10 healthy subjects, as well as in PBMCs obtained in the morning and cultured for 24 hours with exposure to 3-hour hydrocortisone pulses every 6 hours. We used EBV-transformed lymphocytes (EBVLs) as non-synchronized controls. Results GR acetylation was higher in the morning than in the evening in PBMCs, mirroring the fluctuations of circulating cortisol in reverse phase. All known glucocorticoid-responsive genes tested responded as expected to hydrocortisone in non-synchronized EBVLs, however, some of these genes did not show the expected diurnal mRNA fluctuations in PBMCs in vivo. Instead, their mRNA oscillated in a Clock- and a GR acetylation-dependent fashion in naturally synchronized PBMCs cultured ex vivo in the absence of the endogenous glucocorticoid, suggesting that circulating cortisol might prevent circadian GR acetylation-dependent effects in some glucocorticoid-responsive genes in vivo. Conclusions Peripheral CLOCK-mediated circadian acetylation of the human GR may function as a target-tissue, gene-specific counter regulatory mechanism to the actions of diurnally fluctuating cortisol, effectively decreasing tissue sensitivity to glucocorticoids in the morning and increasing it at night. PMID:21980503

  17. Peripheral CLOCK regulates target-tissue glucocorticoid receptor transcriptional activity in a circadian fashion in man.

    Directory of Open Access Journals (Sweden)

    Evangelia Charmandari

    Full Text Available Circulating cortisol fluctuates diurnally under the control of the "master" circadian CLOCK, while the peripheral "slave" counterpart of the latter regulates the transcriptional activity of the glucocorticoid receptor (GR at local glucocorticoid target tissues through acetylation. In this manuscript, we studied the effect of CLOCK-mediated GR acetylation on the sensitivity of peripheral tissues to glucocorticoids in humans.We examined GR acetylation and mRNA expression of GR, CLOCK-related and glucocorticoid-responsive genes in peripheral blood mononuclear cells (PBMCs obtained at 8 am and 8 pm from 10 healthy subjects, as well as in PBMCs obtained in the morning and cultured for 24 hours with exposure to 3-hour hydrocortisone pulses every 6 hours. We used EBV-transformed lymphocytes (EBVLs as non-synchronized controls.GR acetylation was higher in the morning than in the evening in PBMCs, mirroring the fluctuations of circulating cortisol in reverse phase. All known glucocorticoid-responsive genes tested responded as expected to hydrocortisone in non-synchronized EBVLs, however, some of these genes did not show the expected diurnal mRNA fluctuations in PBMCs in vivo. Instead, their mRNA oscillated in a Clock- and a GR acetylation-dependent fashion in naturally synchronized PBMCs cultured ex vivo in the absence of the endogenous glucocorticoid, suggesting that circulating cortisol might prevent circadian GR acetylation-dependent effects in some glucocorticoid-responsive genes in vivo.Peripheral CLOCK-mediated circadian acetylation of the human GR may function as a target-tissue, gene-specific counter regulatory mechanism to the actions of diurnally fluctuating cortisol, effectively decreasing tissue sensitivity to glucocorticoids in the morning and increasing it at night.

  18. New gene targets for glucagon-like peptide-1 during embryonic development and in undifferentiated pluripotent cells.

    Science.gov (United States)

    Sanz, Carmen; Blázquez, Enrique

    2011-09-01

    In humans, glucagon-like peptide (GLP-1) functions during adult life as an incretin hormone with anorexigenic and antidiabetogenic properties. Also, the therapeutic potential of GLP-1 in preventing the adipocyte hyperplasia associated with obesity and in bolstering the maintenance of human mesenchymal stem cell (hMSC) stores by promoting the proliferation and cytoprotection of hMSC seems to be relevant. Since these observations suggest a role for GLP-1 during developmental processes, the aim of the present work was to characterize GLP-1 in early development as well as its gene targets in mouse embryonic stem (mES) cells. Mouse embryos E6, E8, and E10.5 and pluripotent mES were used for the inmunodetection of GLP-1 and GLP-1 receptor. Quantitative real-time PCR was used to determine the expression levels of GLP-1R in several tissues from E12.5 mouse embryos. Additionally, GLP-1 gene targets were studied in mES by multiple gene expression analyses. GLP-1 and its receptors were identified in mES and during embryonic development. In pluripotent mES, GLP-1 modified the expression of endodermal, ectodermal, and mesodermal gene markers as well as sonic hedgehog, noggin, members of the fibroblast and hepatic growth factor families, and others involved in pancreatic development. Additionally, GLP-1 promoted the expression of the antiapoptotic gene bcl2 and at the same time reduced proapoptotic caspase genes. Our results indicate that apart from the effects and therapeutic benefits of GLP-1 in adulthood, it may have additional gene targets in mES cells during embryonic life. Furthermore, the pathophysiological implications of GLP-1 imbalance in adulthood may have a counterpart during development.

  19. In Vitro-Assembled Alphavirus Core-Like Particles Maintain a Structure Similar to That of Nucleocapsid Cores in Mature Virus

    OpenAIRE

    Mukhopadhyay, Suchetana; Chipman, Paul R.; Hong, Eunmee M.; Kuhn, Richard J.; Rossmann, Michael G.

    2002-01-01

    In vitro-assembled core-like particles produced from alphavirus capsid protein and nucleic acid were studied by cryoelectron microscopy. These particles were found to have a diameter of 420 Å with 240 copies of the capsid protein arranged in a T=4 icosahedral surface lattice, similar to the nucleocapsid core in mature virions. However, when the particles were subjected to gentle purification procedures, they were damaged, preventing generation of reliable structural information. Similarly, pu...

  20. Goose parvovirus structural proteins expressed by recombinant baculoviruses self-assemble into virus-like particles with strong immunogenicity in goose

    International Nuclear Information System (INIS)

    Ju, Huanyu; Wei, Na; Wang, Qian; Wang, Chunyuan; Jing, Zhiqiang; Guo, Lu; Liu, Dapeng; Gao, Mingchun; Ma, Bo; Wang, Junwei

    2011-01-01

    Highlights: → All three capsid proteins can be expressed in insect cells in baculovirus expression system. → All three recombinant proteins were spontaneously self-assemble into virus-like particles whose size and appearance were similar to those of native purified GPV virions. → The immunogenicity of GPV-VLPs was better than commercial inactivated vaccine and attenuated vaccine. -- Abstract: Goose parvovirus (GPV), a small non-enveloped ssDNA virus, can cause Derzsy's disease, and three capsid proteins of VP1, VP2, and VP3 are encoded by an overlapping nucleotide sequence. However, little is known on whether recombinant viral proteins (VPs) could spontaneously assemble into virus-like particles (VLPs) in insect cells and whether these VLPs could retain their immunoreactivity and immunogenicity in susceptible geese. To address these issues, genes for these GPV VPs were amplified by PCR, and the recombinant VPs proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures, immunoreactivity, and immunogenicity. The rVP1, rVP2, and rVP3 expressed in Sf9 cells were detected by anti-GPV sera, anti-VP3 sera, and anti-His antibodies, respectively. Electron microscopy revealed that these rVPs spontaneously assembled into VLPs in insect cells, similar to that of the purified wild-type GPV virions. In addition, vaccination with individual types of VLPs, particularly with the rVP2-VLPs, induced higher titers of antibodies and neutralized different strains of GPVs in primary goose and duck embryo fibroblast cells in vitro. These data indicated that these VLPs retained immunoreactivity and had strong immunogenicity in susceptible geese. Therefore, our findings may provide a framework for development of new vaccines for the prevention of Derzsy's disease and vehicles for the delivery of drugs.

  1. Goose parvovirus structural proteins expressed by recombinant baculoviruses self-assemble into virus-like particles with strong immunogenicity in goose

    Energy Technology Data Exchange (ETDEWEB)

    Ju, Huanyu; Wei, Na; Wang, Qian; Wang, Chunyuan; Jing, Zhiqiang; Guo, Lu; Liu, Dapeng; Gao, Mingchun; Ma, Bo [College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China); Wang, Junwei, E-mail: jwwang@neau.edu.cn [College of Veterinary Medicine, Northeast Agricultural University, Harbin, Heilongjiang 150030 (China)

    2011-05-27

    Highlights: {yields} All three capsid proteins can be expressed in insect cells in baculovirus expression system. {yields} All three recombinant proteins were spontaneously self-assemble into virus-like particles whose size and appearance were similar to those of native purified GPV virions. {yields} The immunogenicity of GPV-VLPs was better than commercial inactivated vaccine and attenuated vaccine. -- Abstract: Goose parvovirus (GPV), a small non-enveloped ssDNA virus, can cause Derzsy's disease, and three capsid proteins of VP1, VP2, and VP3 are encoded by an overlapping nucleotide sequence. However, little is known on whether recombinant viral proteins (VPs) could spontaneously assemble into virus-like particles (VLPs) in insect cells and whether these VLPs could retain their immunoreactivity and immunogenicity in susceptible geese. To address these issues, genes for these GPV VPs were amplified by PCR, and the recombinant VPs proteins were expressed in insect cells using a baculovirus expression system for the characterization of their structures, immunoreactivity, and immunogenicity. The rVP1, rVP2, and rVP3 expressed in Sf9 cells were detected by anti-GPV sera, anti-VP3 sera, and anti-His antibodies, respectively. Electron microscopy revealed that these rVPs spontaneously assembled into VLPs in insect cells, similar to that of the purified wild-type GPV virions. In addition, vaccination with individual types of VLPs, particularly with the rVP2-VLPs, induced higher titers of antibodies and neutralized different strains of GPVs in primary goose and duck embryo fibroblast cells in vitro. These data indicated that these VLPs retained immunoreactivity and had strong immunogenicity in susceptible geese. Therefore, our findings may provide a framework for development of new vaccines for the prevention of Derzsy's disease and vehicles for the delivery of drugs.

  2. Fuel assembly

    International Nuclear Information System (INIS)

    Abe, Hideaki; Sakai, Takao; Ishida, Tomio; Yokota, Norikatsu.

    1992-01-01

    The lower ends of a plurality of plate-like shape memory alloys are secured at the periphery of the upper inside of the handling head of a fuel assembly. As the shape memory alloy, a Cu-Zn alloy, a Ti-Pd alloy or a Fe-Ni alloy is used. When high temperature coolants flow out to the handling head, the shape memory alloy deforms by warping to the outer side more greatly toward the upper portion thereof with the temperature increase of the coolants. As the result, the shape of the flow channel of the coolants is changed so as to enlarge at the exit of the upper end of the fuel assembly. Then, the pressure loss of the coolants in the fuel assembly is decreased by the enlargement. Accordingly, the flow rate of the coolants in the fuel assembly is increased to lower the temperature of the coolants. Further, high temperature coolants and low temperature coolants are mixed sufficiently just above the fuel assembly. This can suppress the temperature fluctuation of the mixed coolants in the upper portion of the reactor core, thereby enabling to decrease a fatigue and failures of the structural components in the upper portion of the reactor core. (I.N.)

  3. Synthesis of embryonic tendon-like tissue by human marrow stromal/mesenchymal stem cells requires a three-dimensional environment and transforming growth factor β3.

    Science.gov (United States)

    Kapacee, Zoher; Yeung, Ching-Yan Chloé; Lu, Yinhui; Crabtree, David; Holmes, David F; Kadler, Karl E

    2010-10-01

    Tendon-like tissue generated from stem cells in vitro has the potential to replace tendons and ligaments lost through injury and disease. However, thus far, no information has been available on the mechanism of tendon formation in vitro and how to accelerate the process. We show here that human mesenchymal stem cells (MSCs) and bone marrow-derived mononuclear cells (BM-MNCs) can generate tendon-like tissue in 7days mediated by transforming growth factor (TGF) β3. MSCs cultured in fixed-length fibrin gels spontaneously synthesized narrow-diameter collagen fibrils and exhibited fibripositors (actin-rich, collagen fibril-containing plasma membrane protrusions) identical to those that occur in embryonic tendon. In contrast, BM-MNCs did not synthesize tendon-like tissue under these conditions. We performed real-time PCR analysis of MSCs and BM-MNCs. MSCs upregulated genes encoding type I collagen, TGFβ3, and Smad2 at the time of maximum contraction of the tendon-like tissue (7days). Western blot analysis showed phosphorylation of Smad2 at maximum contraction. The TGFβ inhibitor SB-431542, blocked the phosphorylation of Smad2 and stopped the formation of tendon-like tissue. Quantitative PCR showed that BM-MNCs expressed very low levels of TGFβ3 compared to MSCs. Therefore we added exogenous TGFβ3 protein to BM-MNCs in fibrin gels, which resulted in phosphorylation of Smad2, synthesis of collagen fibrils, the appearance of fibripositors at the plasma membrane, and the formation of tendon-like tissue. In conclusion, MSCs that self-generate TGFβ signaling or the addition of TGFβ3 protein to BM-MNCs in fixed-length fibrin gels spontaneously make embryonic tendon-like tissue in vitro within 7days. Copyright © 2010 International Society of Matrix Biology. Published by Elsevier B.V. All rights reserved.

  4. Cell and Tissue Imaging with Molecularly Imprinted Polymers.

    Science.gov (United States)

    Panagiotopoulou, Maria; Kunath, Stephanie; Haupt, Karsten; Tse Sum Bui, Bernadette

    2017-01-01

    Advanced tools for cell imaging are of particular interest as they can detect, localize and quantify molecular targets like abnormal glycosylation sites that are biomarkers of cancer and infection. Targeting these biomarkers is often challenging due to a lack of receptor materials. Molecularly imprinted polymers (MIPs) are promising artificial receptors; they can be tailored to bind targets specifically, be labeled easily, and are physically and chemically stable. Herein, we demonstrate the application of MIPs as artificial antibodies for selective labeling and imaging of cellular targets, on the example of hyaluronan and sialylation moieties on fixated human skin cells and tissues. Thus, fluorescently labeled MIP nanoparticles templated with glucuronic acid (MIPGlcA) and N-acetylneuraminic acid (MIPNANA) are respectively applied. Two different fluorescent probes are used: (1) MIPGlcA particles, ~400 nm in size are labeled with the dye rhodamine that target the extracellular hyaluronan on cells and tissue specimens and (2) MIP-coated InP/ZnS quantum dots (QDs) of two different colors, ~125 nm in size that target the extracellular and intracellular hyaluronan and sialylation sites. Green and red emitting QDs are functionalized with MIPGlcA and MIPNANA respectively, enabling multiplexed cell imaging. This is a general approach that can also be adapted to other target molecules on and in cells.

  5. Dynamic culture induces a cell type-dependent response impacting on the thickness of engineered connective tissues.

    Science.gov (United States)

    Fortier, Guillaume Marceau; Gauvin, Robert; Proulx, Maryse; Vallée, Maud; Fradette, Julie

    2013-04-01

    Mesenchymal cells are central to connective tissue homeostasis and are widely used for tissue-engineering applications. Dermal fibroblasts and adipose-derived stromal cells (ASCs) allow successful tissue reconstruction by the self-assembly approach of tissue engineering. This method leads to the production of multilayered tissues, devoid of exogenous biomaterials, that can be used as stromal compartments for skin or vesical reconstruction. These tissues are formed by combining cell sheets, generated through cell stimulation with ascorbic acid, which favours the cell-derived production/organization of matrix components. Since media motion can impact on cell behaviour, we investigated the effect of dynamic culture on mesenchymal cells during tissue reconstruction, using the self-assembly method. Tissues produced using ASCs in the presence of a wave-like movement were nearly twice thicker than under standard conditions, while no difference was observed for tissues produced from dermal fibroblasts. The increased matrix deposition was not correlated with an increased proliferation of ASCs, or by higher transcript levels of fibronectin or collagens I and III. A 30% increase of type V collagen mRNA was observed. Interestingly, tissues engineered from dermal fibroblasts featured a four-fold higher level of MMP-1 transcripts under dynamic conditions. Mechanical properties were similar for tissues reconstructed using dynamic or static conditions. Finally, cell sheets produced using ASCs under dynamic conditions could readily be manipulated, resulting in a 2 week reduction of the production time (from 5 to 3 weeks). Our results describe a distinctive property of ASCs' response to media motion, indicating that their culture under dynamic conditions leads to optimized tissue engineering. Copyright © 2011 John Wiley & Sons, Ltd.

  6. A Comparison of Bone Marrow and Cord Blood Mesenchymal Stem Cells for Cartilage Self-Assembly.

    Science.gov (United States)

    White, Jamie L; Walker, Naomi J; Hu, Jerry C; Borjesson, Dori L; Athanasiou, Kyriacos A

    2018-04-02

    Joint injury is a common cause of premature retirement for the human and equine athlete alike. Implantation of engineered cartilage offers the potential to increase the success rate of surgical intervention and hasten recovery times. Mesenchymal stem cells (MSCs) are a particularly attractive cell source for cartilage engineering. While bone marrow-derived MSCs (BM-MSCs) have been most extensively characterized for musculoskeletal tissue engineering, studies suggest that cord blood MSCs (CB-MSCs) may elicit a more robust chondrogenic phenotype. The objective of this study was to determine a superior equine MSC source for cartilage engineering. MSCs derived from bone marrow or cord blood were stimulated to undergo chondrogenesis through aggregate redifferentiation and used to generate cartilage through the self-assembling process. The resulting neocartilage produced from either BM-MSCs or CB-MSCs was compared by measuring mechanical, biochemical, and histological properties. We found that while BM constructs possessed higher tensile properties and collagen content, CB constructs had superior compressive properties comparable to that of native tissue and higher GAG content. Moreover, CB constructs had alkaline phosphatase activity, collagen type X, and collagen type II on par with native tissue suggesting a more hyaline cartilage-like phenotype. In conclusion, while both BM-MSCs and CB-MSCs were able to form neocartilage, CB-MSCs resulted in tissue more closely resembling native equine articular cartilage as determined by a quantitative functionality index. Therefore, CB-MSCs are deemed a superior source for the purpose of articular cartilage self-assembly.

  7. Impact analysis of spent fuel jacket assemblies

    International Nuclear Information System (INIS)

    Aramayo, G.A.

    1994-01-01

    As part of the analyses performed in support of the reracking of the High Flux Isotope Reactor pool, it became necessary to prove the structural integrity of the spent fuel jacket assemblies subjected to gravity drop that result from postulated accidents associated with the handling of these assemblies while submerged in the pool. The spent fuel jacket assemblies are an integral part of the reracking project, and serve to house fuel assemblies. The structure integrity of the jacket assemblies from loads that result from impact from a height of 10 feet onto specified targets has been performed analytically using the computer program LS-DYNA3D. Nine attitudes of the assembly at the time of impact have been considered. Results of the analyses show that there is no failure of the assemblies as a result of the impact scenarios considered

  8. Challenges, Solutions, and Quality Metrics of Personal Genome Assembly in Advancing Precision Medicine

    Directory of Open Access Journals (Sweden)

    Wenming Xiao

    2016-04-01

    Full Text Available Even though each of us shares more than 99% of the DNA sequences in our genome, there are millions of sequence codes or structure in small regions that differ between individuals, giving us different characteristics of appearance or responsiveness to medical treatments. Currently, genetic variants in diseased tissues, such as tumors, are uncovered by exploring the differences between the reference genome and the sequences detected in the diseased tissue. However, the public reference genome was derived with the DNA from multiple individuals. As a result of this, the reference genome is incomplete and may misrepresent the sequence variants of the general population. The more reliable solution is to compare sequences of diseased tissue with its own genome sequence derived from tissue in a normal state. As the price to sequence the human genome has dropped dramatically to around $1000, it shows a promising future of documenting the personal genome for every individual. However, de novo assembly of individual genomes at an affordable cost is still challenging. Thus, till now, only a few human genomes have been fully assembled. In this review, we introduce the history of human genome sequencing and the evolution of sequencing platforms, from Sanger sequencing to emerging “third generation sequencing” technologies. We present the currently available de novo assembly and post-assembly software packages for human genome assembly and their requirements for computational infrastructures. We recommend that a combined hybrid assembly with long and short reads would be a promising way to generate good quality human genome assemblies and specify parameters for the quality assessment of assembly outcomes. We provide a perspective view of the benefit of using personal genomes as references and suggestions for obtaining a quality personal genome. Finally, we discuss the usage of the personal genome in aiding vaccine design and development, monitoring host

  9. Inverse Problem in Self-assembly

    Science.gov (United States)

    Tkachenko, Alexei

    2012-02-01

    By decorating colloids and nanoparticles with DNA, one can introduce highly selective key-lock interactions between them. This leads to a new class of systems and problems in soft condensed matter physics. In particular, this opens a possibility to solve inverse problem in self-assembly: how to build an arbitrary desired structure with the bottom-up approach? I will present a theoretical and computational analysis of the hierarchical strategy in attacking this problem. It involves self-assembly of particular building blocks (``octopus particles''), that in turn would assemble into the target structure. On a conceptual level, our approach combines elements of three different brands of programmable self assembly: DNA nanotechnology, nanoparticle-DNA assemblies and patchy colloids. I will discuss the general design principles, theoretical and practical limitations of this approach, and illustrate them with our simulation results. Our crucial result is that not only it is possible to design a system that has a given nanostructure as a ground state, but one can also program and optimize the kinetic pathway for its self-assembly.

  10. Design strategies to address the effect of hydrophobic epitope on stability and in vitro assembly of modular virus‐like particle

    Science.gov (United States)

    Tekewe, Alemu; Connors, Natalie K.; Middelberg, Anton P. J.

    2016-01-01

    Abstract Virus‐like particles (VLPs) and capsomere subunits have shown promising potential as safe and effective vaccine candidates. They can serve as platforms for the display of foreign epitopes on their surfaces in a modular architecture. Depending on the physicochemical properties of the antigenic modules, modularization may affect the expression, solubility and stability of capsomeres, and VLP assembly. In this study, three module designs of a rotavirus hydrophobic peptide (RV10) were synthesized using synthetic biology. Among the three synthetic modules, modularization of the murine polyomavirus VP1 with a single copy of RV10 flanked by long linkers and charged residues resulted in the expression of stable modular capsomeres. Further employing the approach of module titration of RV10 modules on each capsomere via Escherichia coli co‐expression of unmodified VP1 and modular VP1‐RV10 successfully translated purified modular capomeres into modular VLPs when assembled in vitro. Our results demonstrate that tailoring the physicochemical properties of modules to enhance modular capsomeres stability is achievable through synthetic biology designs. Combined with module titration strategy to avoid steric hindrance to intercapsomere interactions, this allows bioprocessing of bacterially produced in vitro assembled modular VLPs. PMID:27222486

  11. Integrin-mediated targeting of protein polymer nanoparticles carrying a cytostatic macrolide

    Science.gov (United States)

    Shi, Pu

    Cytotoxicity, low water solubility, rapid clearance from circulation, and offtarget side-effects are common drawbacks of conventional small-molecule drugs. To overcome these shortcomings, many multifunctional nanocarriers have been proposed to enhance drug delivery. In concept, multifunctional nanoparticles might carry multiple agents, control release rate, biodegrade, and utilize target-mediated drug delivery; however, the design of these particles presents many challenges at the stage of pharmaceutical development. An emerging solution to improve control over these particles is to turn to genetic engineering. Genetically engineered nanocarriers are precisely controlled in size and structure and can provide specific control over sites for chemical attachment of drugs. Genetically engineered drug carriers that assemble nanostructures including nanoparticles and nanofibers can be polymeric or nonpolymeric. This chapter summarizes the recent development of applications in drug and gene delivery utilizing nanostructures of polymeric genetically engineered drug carriers such as elastin-like polypeptides, silk-like polypeptides, and silk-elastin-like protein polymers, and non-polymeric genetically engineered drug carriers such as vault proteins and viral proteins. This chapter explores an alternative encapsulation strategy based on high-specificity avidity between a small molecule drug and its cognate protein target fused to the corona of protein polymer nanoparticles. With the new strategy, the drug associates tightly to the carrier and releases slowly, which may decrease toxicity and promote tumor accumulation via the enhanced permeability and retention effect. To test this hypothesis, the drug Rapamycin (Rapa) was selected for its potent anti-proliferative properties, which give it immunosuppressant and anti-tumor activity. Despite its potency, Rapa has low solubility, low oral bioavailability, and rapid systemic clearance, which make it an excellent candidate for

  12. 3D Printing of Personalized Organs and Tissues

    Science.gov (United States)

    Ye, Kaiming

    2015-03-01

    Authors: Kaiming Ye and Sha Jin, Department of Biomedical Engineering, Watson School of Engineering and Applied Science, Binghamton University, State University of New York, Binghamton, NY 13902-6000 Abstract: Creation of highly organized multicellular constructs, including tissues and organs or organoids, will revolutionize tissue engineering and regenerative medicine. The development of these technologies will enable the production of individualized organs or tissues for patient-tailored organ transplantation or cell-based therapy. For instance, a patient with damaged myocardial tissues due to an ischemic event can receive a myocardial transplant generated using the patient's own induced pluripotent stem cells (iPSCs). Likewise, a type-1 diabetic patient can be treated with lab-generated islets to restore his or her physiological insulin secretion capability. These lab-produced, high order tissues or organs can also serve as disease models for pathophysiological study and drug screening. The remarkable advances in stem cell biology, tissue engineering, microfabrication, and materials science in the last decade suggest the feasibility of generating these tissues and organoids in the laboratory. Nevertheless, major challenges still exist. One of the critical challenges that we still face today is the difficulty in constructing or fabricating multicellular assemblies that recapitulate in vivo microenvironments essential for controlling cell proliferation, migration, differentiation, maturation and assembly into a biologically functional tissue or organoid structure. These challenges can be addressed through developing 3D organ and tissue printing which enables organizing and assembling cells into desired tissue and organ structures. We have shown that human pluripotent stem cells differentiated in 3D environments are mature and possess high degree of biological function necessary for them to function in vivo.

  13. Do Neuroendocrine Peptides and Their Receptors Qualify as Novel Therapeutic Targets in Osteoarthritis?

    Directory of Open Access Journals (Sweden)

    Susanne Grässel

    2018-01-01

    Full Text Available Joint tissues like synovium, articular cartilage, meniscus and subchondral bone, are targets for neuropeptides. Resident cells of these tissues express receptors for various neuroendocrine-derived peptides including proopiomelanocortin (POMC-derived peptides, i.e., α-melanocyte-stimulating hormone (α-MSH, adrenocorticotropin (ACTH and β-endorphin (β-ED, and sympathetic neuropeptides like vasoactive intestinal peptide (VIP and neuropeptide y (NPY. Melanocortins attained particular attention due to their immunomodulatory and anti-inflammatory effects in several tissues and organs. In particular, α-MSH, ACTH and specific melanocortin-receptor (MCR agonists appear to have promising anti-inflammatory actions demonstrated in animal models of experimentally induced arthritis and osteoarthritis (OA. Sympathetic neuropeptides have obtained increasing attention as they have crucial trophic effects that are critical for joint tissue and bone homeostasis. VIP and NPY are implicated in direct and indirect activation of several anabolic signaling pathways in bone and synovial cells. Additionally, pituitary adenylate cyclase-activating polypeptide (PACAP proved to be chondroprotective and, thus, might be a novel target in OA. Taken together, it appears more and more likely that the anabolic effects of these neuroendocrine peptides or their respective receptor agonists/antagonists may be exploited for the treatment of patients with inflammatory and degenerative joint diseases in the future.

  14. Preliminary High-Throughput Metagenome Assembly

    Energy Technology Data Exchange (ETDEWEB)

    Dusheyko, Serge; Furman, Craig; Pangilinan, Jasmyn; Shapiro, Harris; Tu, Hank

    2007-03-26

    Metagenome data sets present a qualitatively different assembly problem than traditional single-organism whole-genome shotgun (WGS) assembly. The unique aspects of such projects include the presence of a potentially large number of distinct organisms and their representation in the data set at widely different fractions. In addition, multiple closely related strains could be present, which would be difficult to assemble separately. Failure to take these issues into account can result in poor assemblies that either jumble together different strains or which fail to yield useful results. The DOE Joint Genome Institute has sequenced a number of metagenomic projects and plans to considerably increase this number in the coming year. As a result, the JGI has a need for high-throughput tools and techniques for handling metagenome projects. We present the techniques developed to handle metagenome assemblies in a high-throughput environment. This includes a streamlined assembly wrapper, based on the JGI?s in-house WGS assembler, Jazz. It also includes the selection of sensible defaults targeted for metagenome data sets, as well as quality control automation for cleaning up the raw results. While analysis is ongoing, we will discuss preliminary assessments of the quality of the assembly results (http://fames.jgi-psf.org).

  15. Tissue factor is an angiogenic-specific receptor for factor VII-targeted immunotherapy and photodynamic therapy.

    Science.gov (United States)

    Hu, Zhiwei; Cheng, Jijun; Xu, Jie; Ruf, Wolfram; Lockwood, Charles J

    2017-02-01

    Identification of target molecules specific for angiogenic vascular endothelial cells (VEC), the inner layer of pathological neovasculature, is critical for discovery and development of neovascular-targeting therapy for angiogenesis-dependent human diseases, notably cancer, macular degeneration and endometriosis, in which vascular endothelial growth factor (VEGF) plays a central pathophysiological role. Using VEGF-stimulated vascular endothelial cells (VECs) isolated from microvessels, venous and arterial blood vessels as in vitro angiogenic models and unstimulated VECs as a quiescent VEC model, we examined the expression of tissue factor (TF), a membrane-bound receptor on the angiogenic VEC models compared with quiescent VEC controls. We found that TF is specifically expressed on angiogenic VECs in a time-dependent manner in microvessels, venous and arterial vessels. TF-targeted therapeutic agents, including factor VII (fVII)-IgG1 Fc and fVII-conjugated photosensitizer, can selectively bind angiogenic VECs, but not the quiescent VECs. Moreover, fVII-targeted photodynamic therapy can selectively and completely eradicate angiogenic VECs. We conclude that TF is an angiogenic-specific receptor and the target molecule for fVII-targeted therapeutics. This study supports clinical trials of TF-targeted therapeutics for the treatment of angiogenesis-dependent diseases such as cancer, macular degeneration and endometriosis.

  16. Combined scanning probe and light scattering characterization of multi-stage self-assembly of targeted liposome-based delivery systems

    International Nuclear Information System (INIS)

    Farkas, N; Dagata, J A; Yang, C; Rait, A; Pirollo, K F; Chang, E H

    2011-01-01

    The mean size and size distribution of a targeted nanoparticle delivery system (NDS) strongly influences the intrinsic stability and functionality of this molecular complex, affects its performance as a systemic drug delivery platform and ultimately determines its efficacy toward early detection and treatment of cancer. Since its components undergo significant reorganization during multiple stages of self-assembly, it is essential to monitor the size and stability of the complex throughout the NDS formulation in order to ensure its potency and manufacturability prior to entering clinical trials. This work combines scanning probe microscopy (SPM) and dynamic light scattering (DLS) techniques to obtain quantitative and reliable size measurements of the NDS, and to investigate how variations in the NDS formulation or self-assembly process impact the size, structure and functionality of the complex with various therapeutic and diagnostic agent payloads. These combined SPM and DLS methods, when implemented at an early stage of the NDS formulation, present a potential measurement approach to facilitate drug discovery and development, optimization and quality control during manufacturing of the NDS

  17. Monocyte-mediated delivery of polymeric backpacks to inflamed tissues: a generalized strategy to deliver drugs to treat inflammation.

    Science.gov (United States)

    Anselmo, Aaron C; Gilbert, Jonathan B; Kumar, Sunny; Gupta, Vivek; Cohen, Robert E; Rubner, Michael F; Mitragotri, Samir

    2015-02-10

    Targeted delivery of drugs and imaging agents to inflamed tissues, as in the cases of cancer, Alzheimer's disease, Parkinson's disease, and arthritis, represents one of the major challenges in drug delivery. Monocytes possess a unique ability to target and penetrate into sites of inflammation. Here, we describe a broad approach to take advantage of the natural ability of monocytes to target and deliver flat polymeric particles ("Cellular Backpacks") to inflamed tissues. Cellular backpacks attach strongly to the surface of monocytes but do not undergo phagocytosis due to backpack's size, disk-like shape and flexibility. Following attachment of backpacks, monocytes retain important cellular functions including transmigration through an endothelial monolayer and differentiation into macrophages. In two separate in vivo inflammation models, backpack-laden monocytes exhibit increased targeting to inflamed tissues. Cellular backpacks, and their abilities to attach to monocytes without impairing monocyte functions and 'hitchhike' to a variety of inflamed tissues, offer a new platform for both cell-mediated therapies and broad targeting of inflamed tissues. Copyright © 2014 Elsevier B.V. All rights reserved.

  18. Tissue vascularization with endothelial-like mesenchymal stromal cells

    NARCIS (Netherlands)

    Portalska, K.K.

    2014-01-01

    Although most tissues in the human body have self-renewal capabilities, there are defects, e.g. caused by trauma or disease, which are beyond regenerative potential. Tissue engineering offers a possibility to heal such defects without the necessity of finding a suitable graft donor. While a number

  19. A simple and efficient method for assembling TALE protein based on plasmid library.

    Science.gov (United States)

    Zhang, Zhiqiang; Li, Duo; Xu, Huarong; Xin, Ying; Zhang, Tingting; Ma, Lixia; Wang, Xin; Chen, Zhilong; Zhang, Zhiying

    2013-01-01

    DNA binding domain of the transcription activator-like effectors (TALEs) from Xanthomonas sp. consists of tandem repeats that can be rearranged according to a simple cipher to target new DNA sequences with high DNA-binding specificity. This technology has been successfully applied in varieties of species for genome engineering. However, assembling long TALE tandem repeats remains a big challenge precluding wide use of this technology. Although several new methodologies for efficiently assembling TALE repeats have been recently reported, all of them require either sophisticated facilities or skilled technicians to carry them out. Here, we described a simple and efficient method for generating customized TALE nucleases (TALENs) and TALE transcription factors (TALE-TFs) based on TALE repeat tetramer library. A tetramer library consisting of 256 tetramers covers all possible combinations of 4 base pairs. A set of unique primers was designed for amplification of these tetramers. PCR products were assembled by one step of digestion/ligation reaction. 12 TALE constructs including 4 TALEN pairs targeted to mouse Gt(ROSA)26Sor gene and mouse Mstn gene sequences as well as 4 TALE-TF constructs targeted to mouse Oct4, c-Myc, Klf4 and Sox2 gene promoter sequences were generated by using our method. The construction routines took 3 days and parallel constructions were available. The rate of positive clones during colony PCR verification was 64% on average. Sequencing results suggested that all TALE constructs were performed with high successful rate. This is a rapid and cost-efficient method using the most common enzymes and facilities with a high success rate.

  20. Structure and vascular tissue expression of duplicated TERMINAL EAR1-like paralogues in poplar.

    Science.gov (United States)

    Charon, Céline; Vivancos, Julien; Mazubert, Christelle; Paquet, Nicolas; Pilate, Gilles; Dron, Michel

    2010-02-01

    TERMINAL EAR1-like (TEL) genes encode putative RNA-binding proteins only found in land plants. Previous studies suggested that they may regulate tissue and organ initiation in Poaceae. Two TEL genes were identified in both Populus trichocarpa and the hybrid aspen Populus tremula x P. alba, named, respectively, PoptrTEL1-2 and PtaTEL1-2. The analysis of the organisation around the PoptrTEL genes in the P. trichocarpa genome and the estimation of the synonymous substitution rate for PtaTEL1-2 genes indicate that the paralogous link between these two Populus TEL genes probably results from the Salicoid large-scale gene-duplication event. Phylogenetic analyses confirmed their orthology link with the other TEL genes. The expression pattern of both PtaTEL genes appeared to be restricted to the mother cells of the plant body: leaf founder cells, leaf primordia, axillary buds and root differentiating tissues, as well as to mother cells of vascular tissues. Most interestingly, PtaTEL1-2 transcripts were found in differentiating cells of secondary xylem and phloem, but probably not in the cambium itself. Taken together, these results indicate specific expression of the TEL genes in differentiating cells controlling tissue and organ development in Populus (and other Angiosperm species).

  1. Tracking targeted bimodal nanovaccines: immune responses and routing in cells, tissue, and whole organism.

    Science.gov (United States)

    Cruz, Luis J; Tacken, Paul J; Zeelenberg, Ingrid S; Srinivas, Mangala; Bonetto, Fernando; Weigelin, Bettina; Eich, Christina; de Vries, I Jolanda; Figdor, Carl G

    2014-12-01

    Dendritic cells (DCs) are the most potent antigen-presenting cells (APCs), involved in the induction of immunity and currently exploited for antitumor immunotherapies. An optimized noninvasive imaging modality capable of determining and quantifying DC-targeted nanoparticle (NP) trajectories could provide valuable information regarding therapeutic vaccine outcome. Here, targeted poly(d,l-lactide-co-glycolide) nanoparticles (PLGA NPs) recognizing DC receptors were equipped with superparamagnetic iron oxide particles (SPIO) or gold nanoparticles with fluorescently labeled antigen. The fluorescent label allowed for rapid analysis and quantification of DC-specific uptake of targeted PLGA NPs in comparison to uptake by other cells. Transmission electron microscopy (TEM) showed that a fraction of the encapsulated antigen reached the lysosomal compartment of DCs, where SPIO and gold were already partially released. However, part of the PLGA NPs localized within the cytoplasm, as confirmed by confocal microscopy. DCs targeted with NPs carrying SPIO or fluorescent antigen were detected within lymph nodes as early as 1 h after injection by magnetic resonance imaging (MRI). Despite the fact that targeting did not markedly affect PLGA NP biodistribution on organism and tissue level, it increased delivery of NPs to DCs residing in peripheral lymph nodes and resulted in enhanced T cell proliferation. In conclusion, two imaging agents within a single carrier allows tracking of targeted PLGA NPs at the subcellular, cellular, and organismal levels, thereby facilitating the rational design of in vivo targeted vaccination strategies.

  2. Dynamic Multi-Component Hemiaminal Assembly

    Science.gov (United States)

    You, Lei; Long, S. Reid; Lynch, Vincent M.

    2012-01-01

    A simple approach to generating in situ metal templated tris-(2-picolyl)amine-like multi-component assemblies with potential applications in molecular recognition and sensing is reported. The assembly is based on the reversible covalent association between di-(2-picolyl)amine and aldehydes. Zinc ion is the best for inducing assembly among the metal salts investigated, while 2-picolinaldehyde is the best among the heterocyclic aldehydes studied. Although an equilibrium constant of 6.6 * 103 M-1 was measured for the assembly formed by 2-picolinaldehdye, di-(2-picolyl)amine, and zinc triflate, the equilibrium constants for other systems are in the 102 M-1 range. X-ray structural analysis revealed that zinc adopts a trigonal bipyramidal geometry within the assembled ligand. The diversity and equilibrium of the assemblies are readily altered by simply changing concentrations, varying components, or adding counter anions. PMID:21919095

  3. Cardiac tissue engineering using perfusion bioreactor systems

    Science.gov (United States)

    Radisic, Milica; Marsano, Anna; Maidhof, Robert; Wang, Yadong; Vunjak-Novakovic, Gordana

    2009-01-01

    This protocol describes tissue engineering of synchronously contractile cardiac constructs by culturing cardiac cell populations on porous scaffolds (in some cases with an array of channels) and bioreactors with perfusion of culture medium (in some cases supplemented with an oxygen carrier). The overall approach is ‘biomimetic’ in nature as it tends to provide in vivo-like oxygen supply to cultured cells and thereby overcome inherent limitations of diffusional transport in conventional culture systems. In order to mimic the capillary network, cells are cultured on channeled elastomer scaffolds that are perfused with culture medium that can contain oxygen carriers. The overall protocol takes 2–4 weeks, including assembly of the perfusion systems, preparation of scaffolds, cell seeding and cultivation, and on-line and end-point assessment methods. This model is well suited for a wide range of cardiac tissue engineering applications, including the use of human stem cells, and high-fidelity models for biological research. PMID:18388955

  4. Tissue remodeling and nonendometrium-like menstrual cycling are hallmarks of peritoneal endometriosis lesions.

    Science.gov (United States)

    Sohler, Florian; Sommer, Anette; Wachter, David L; Agaimy, Abbas; Fischer, Oliver M; Renner, Stefan P; Burghaus, Stefanie; Fasching, Peter A; Beckmann, Matthias W; Fuhrmann, Ulrike; Strick, Reiner; Strissel, Pamela L

    2013-01-01

    We identified differentially expressed genes comparing peritoneal endometriosis lesions (n = 18), eutopic endometrium (n = 17), and peritoneum (n = 22) from the same patients with complete menstrual cycles using microarrays (54 675 probe sets) and immunohistochemistry. Peritoneal lesions and peritoneum demonstrated 3901 and 4973 significantly differentially expressed genes compared to eutopic endometrium, respectively. Peritoneal lesions significantly revealed no correlation with a specific menstrual cycle phase by gene expression and histopathology, exhibited low expressed proliferation genes, and constant levels of steroid hormone receptor genes. Tissue remodeling genes in cytoskeleton, smooth muscle contraction, cellular adhesion, tight junctions, and O-glycan biosynthesis were the most significant to lesions, including desmin and smooth muscle myosin heavy chain 11. Protein expression and location of desmin, alpha-actin, and h-caldesmon in peritoneal lesions discriminated between smooth muscle hyperplasia and metaplasia. Peritoneal lesions demonstrate no menstrual cycle phasing but constant steroid hormone receptor expression where a slow but steady growth is linked with tissue remodeling. Our study contributes to the molecular pathology of peritoneal endometriosis and will help to identify clinical targets for treatment and management.

  5. Pancreatic polypeptide: Identification of target tissues and investigation of possible physiologic significance

    International Nuclear Information System (INIS)

    Shetzline, M.A.

    1988-01-01

    Pancreatic Polypeptide (PP) is a 36 amino acid peptide with hormonal properties but whose physiologic function remains unknown. In order to determine the function of this peptide we investigated potential target tissues using an in vivo radioreceptor assay. In vitro high concentrations of unlabeled hormone competitively inhibit low concentrations of labeled hormone from binding to receptors. Our in vivo studies indicate that, in the presence of concentrated unlabeled peptide, labeled PP distributes between the plasma and interstitial fluid. When saline rather than excess unlabeled PP is injected, the labeled peptide appears to distribute in a volume exceeding the combined plasma and interstitial fluid volume of tissue. The distribution volume which exceeds the anatomic extracellular volume and which is not present with excess unlabeled peptide, is the receptor compartment. With this assay we demonstrated in the rat specific and displaceable PP binding to the ductus choledochus, duodenum, ileum, and adrenal gland. In vitro rat adrenal cell membranes showed specific I-125 labeled PP binding. Specific binding also occurred in bovine cortical and medullary membranes

  6. Targeted gene disruption by use of transcription activator-like effector nuclease (TALEN) in the water flea Daphnia pulex.

    Science.gov (United States)

    Hiruta, Chizue; Ogino, Yukiko; Sakuma, Tetsushi; Toyota, Kenji; Miyagawa, Shinichi; Yamamoto, Takashi; Iguchi, Taisen

    2014-11-18

    The cosmopolitan microcrustacean Daphnia pulex provides a model system for both human health research and monitoring ecosystem integrity. It is the first crustacean to have its complete genome sequenced, an unprecedented ca. 36% of which has no known homologs with any other species. Moreover, D. pulex is ideally suited for experimental manipulation because of its short reproductive cycle, large numbers of offspring, synchronization of oocyte maturation, and other life history characteristics. However, existing gene manipulation techniques are insufficient to accurately define gene functions. Although our previous investigations developed an RNA interference (RNAi) system in D. pulex, the possible time period of functional analysis was limited because the effectiveness of RNAi is transient. Thus, in this study, we developed a genome editing system for D. pulex by first microinjecting transcription activator-like effector nuclease (TALEN) mRNAs into early embryos and then evaluating TALEN activity and mutation phenotypes. We assembled a TALEN construct specific to the Distal-less gene (Dll), which is a homeobox transcription factor essential for distal limb development in invertebrates and vertebrates, and evaluated its activity in vitro by single-strand annealing assay. Then, we injected TALEN mRNAs into eggs within 1 hour post-ovulation. Injected embryos presented with defects in the second antenna and altered appendage development, and indel mutations were detected in Dll loci, indicating that this technique successfully knocked out the target gene. We succeeded, for the first time in D. pulex, in targeted mutagenesis by use of Platinum TALENs. This genome editing technique makes it possible to conduct reverse genetic analysis in D. pulex, making this species an even more appropriate model organism for environmental, evolutionary, and developmental genomics.

  7. Toll-like receptors as therapeutic targets in cystic fibrosis.

    LENUS (Irish Health Repository)

    Greene, Catherine M

    2008-12-01

    Background: Toll-like receptors (TLRs) are pattern recognition receptors that act as a first-line of defence in the innate immune response by recognising and responding to conserved molecular patterns in microbial factors and endogenous danger signals. Cystic fibrosis (CF)-affected airways represent a milieu potentially rich in TLR agonists and the chronic inflammatory phenotype evident in CF airway epithelial cells is probably due in large part to activation of TLRs. Objective\\/methods: To examine the prospects of developing novel therapies for CF by targeting TLRs. We outline the expression and function of TLRs and explore the therapeutic potential of naturally-occurring and synthetic TLR inhibitors for CF. Results\\/conclusion: Modulation of TLRs has therapeutic potential for the inflammatory lung manifestations of CF.

  8. Bioprinting synthetic self-assembling peptide hydrogels for biomedical applications

    International Nuclear Information System (INIS)

    Loo, Yihua; Hauser, Charlotte A E

    2016-01-01

    Three-dimensional (3D) bioprinting is a disruptive technology for creating organotypic constructs for high-throughput screening and regenerative medicine. One major challenge is the lack of suitable bioinks. Short synthetic self-assembling peptides are ideal candidates. Several classes of peptides self-assemble into nanofibrous hydrogels resembling the native extracellular matrix. This is a conducive microenvironment for maintaining cell survival and physiological function. Many peptides also demonstrate stimuli-responsive gelation and tuneable mechanical properties, which facilitates extrusion before dispensing and maintains the shape fidelity of the printed construct in aqueous media. The inherent biocompatibility and biodegradability bodes well for in vivo applications as implantable tissues and drug delivery matrices, while their short length and ease of functionalization facilitates synthesis and customization. By applying self-assembling peptide inks to bioprinting, the dynamic complexity of biological tissue can be recreated, thereby advancing current biomedical applications of peptide hydrogel scaffolds. (paper)

  9. Gefarnate stimulates mucin-like glycoprotein secretion in conjunctival tissue and ameliorates corneal epithelial damage in animal dry-eye models

    Directory of Open Access Journals (Sweden)

    Dota A

    2013-01-01

    Full Text Available Atsuyoshi Dota, Yuko Takaoka-Shichijo, Masatsugu NakamuraOphthalmic Research and Development Center, Santen Pharmaceutical Co, Ltd, Ikoma-shi, Nara, JapanPurpose: The aim of this study was to evaluate the effect of gefarnate on mucin-like glycoprotein secretion in isolated rabbit conjunctival tissue, and on corneal epithelial damage in rabbit and cat dry-eye models.Methods: Conjunctival tissue isolated from rabbits was treated with gefarnate. Mucin-like glycoprotein was detected in the culture supernatant by an enzyme-linked lectin assay. Gefarnate ointment was topically applied to eyes once daily for 7 days in the rabbit dry-eye model, in which the lacrimal glands, Harderian gland, and nictitating membrane were removed, or for 4 weeks in the cat dry-eye model, in which the lacrimal gland and nictitating membrane were removed. Corneal epithelial damage was evaluated by measurement of corneal permeability by rose bengal in the rabbit model or by fluorescein staining in the cat model.Results: Gefarnate stimulated mucin-like glycoprotein secretion in conjunctival tissue in a dose-dependent manner. In the rabbit dry-eye model, application of gefarnate ointment to the eyes resulted in a dose-dependent decrease in rose bengal permeability in the cornea, with the effect being significant at concentrations of ≥0.3%. In the cat dry-eye model, application of gefarnate ointment resulted in a significant decrease in the corneal fluorescein staining score.Conclusion: These results suggest that gefarnate stimulates in vitro secretion of mucin-like glycoprotein in conjunctival tissue and ameliorates corneal epithelial damage in animal dry-eye models. Gefarnate may therefore be effective for treating dry eye.Keywords: gefarnate, fluorescein staining, rose bengal permeability, rabbit, cat, dry eye

  10. Cellular self-assembly and biomaterials-based organoid models of development and diseases.

    Science.gov (United States)

    Shah, Shivem B; Singh, Ankur

    2017-04-15

    Organogenesis and morphogenesis have informed our understanding of physiology, pathophysiology, and avenues to create new curative and regenerative therapies. Thus far, this understanding has been hindered by the lack of a physiologically relevant yet accessible model that affords biological control. Recently, three-dimensional ex vivo cellular cultures created through cellular self-assembly under natural extracellular matrix cues or through biomaterial-based directed assembly have been shown to physically resemble and recapture some functionality of target organs. These "organoids" have garnered momentum for their applications in modeling human development and disease, drug screening, and future therapy design or even organ replacement. This review first discusses the self-organizing organoids as materials with emergent properties and their advantages and limitations. We subsequently describe biomaterials-based strategies used to afford more control of the organoid's microenvironment and ensuing cellular composition and organization. In this review, we also offer our perspective on how multifunctional biomaterials with precise spatial and temporal control could ultimately bridge the gap between in vitro organoid platforms and their in vivo counterparts. Several notable reviews have highlighted PSC-derived organoids and 3D aggregates, including embryoid bodies, from a development and cellular assembly perspective. The focus of this review is to highlight the materials-based approaches that cells, including PSCs and others, adopt for self-assembly and the controlled development of complex tissues, such as that of the brain, gut, and immune system. Copyright © 2017 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

  11. Real-time visualization of perforin nanopore assembly

    Science.gov (United States)

    Leung, Carl; Hodel, Adrian W.; Brennan, Amelia J.; Lukoyanova, Natalya; Tran, Sharon; House, Colin M.; Kondos, Stephanie C.; Whisstock, James C.; Dunstone, Michelle A.; Trapani, Joseph A.; Voskoboinik, Ilia; Saibil, Helen R.; Hoogenboom, Bart W.

    2017-05-01

    Perforin is a key protein of the vertebrate immune system. Secreted by cytotoxic lymphocytes as soluble monomers, perforin can self-assemble into oligomeric pores of 10-20 nm inner diameter in the membranes of virus-infected and cancerous cells. These large pores facilitate the entry of pro-apoptotic granzymes, thereby rapidly killing the target cell. To elucidate the pathways of perforin pore assembly, we carried out real-time atomic force microscopy and electron microscopy studies. Our experiments reveal that the pore assembly proceeds via a membrane-bound prepore intermediate state, typically consisting of up to approximately eight loosely but irreversibly assembled monomeric subunits. These short oligomers convert to more closely packed membrane nanopore assemblies, which can subsequently recruit additional prepore oligomers to grow the pore size.

  12. Hydrogel-laden paper scaffold system for origami-based tissue engineering.

    Science.gov (United States)

    Kim, Su-Hwan; Lee, Hak Rae; Yu, Seung Jung; Han, Min-Eui; Lee, Doh Young; Kim, Soo Yeon; Ahn, Hee-Jin; Han, Mi-Jung; Lee, Tae-Ik; Kim, Taek-Soo; Kwon, Seong Keun; Im, Sung Gap; Hwang, Nathaniel S

    2015-12-15

    In this study, we present a method for assembling biofunctionalized paper into a multiform structured scaffold system for reliable tissue regeneration using an origami-based approach. The surface of a paper was conformally modified with a poly(styrene-co-maleic anhydride) layer via initiated chemical vapor deposition followed by the immobilization of poly-l-lysine (PLL) and deposition of Ca(2+). This procedure ensures the formation of alginate hydrogel on the paper due to Ca(2+) diffusion. Furthermore, strong adhesion of the alginate hydrogel on the paper onto the paper substrate was achieved due to an electrostatic interaction between the alginate and PLL. The developed scaffold system was versatile and allowed area-selective cell seeding. Also, the hydrogel-laden paper could be folded freely into 3D tissue-like structures using a simple origami-based method. The cylindrically constructed paper scaffold system with chondrocytes was applied into a three-ring defect trachea in rabbits. The transplanted engineered tissues replaced the native trachea without stenosis after 4 wks. As for the custom-built scaffold system, the hydrogel-laden paper system will provide a robust and facile method for the formation of tissues mimicking native tissue constructs.

  13. Liver tissue engineering based on aggregate assembly: efficient formation of endothelialized rat hepatocyte aggregates and their immobilization with biodegradable fibres

    International Nuclear Information System (INIS)

    Pang, Y; Shinohara, M; Komori, K; Sakai, Y; Montagne, K

    2012-01-01

    To realize long-term in vitro culture of hepatocytes at a high density while maintaining a high hepatic function for aggregate-based liver tissue engineering, we report here a novel culture method whereby endothelialized rat hepatocyte aggregates were formed using a PDMS microwell device and cultured in a perfusion bioreactor by introducing spacers between aggregates to improve oxygen and nutrient supply. Primary rat hepatocyte aggregates around 100 µm in diameter coated with human umbilical vein endothelial cells were spontaneously and quickly formed after 12 h of incubation, thanks to the continuous supply of oxygen by diffusion through the PDMS honeycomb microwell device. Then, the recovered endothelialized rat hepatocyte aggregates were mixed with biodegradable poly-l-lactic acid fibres in suspension and packed into a PDMS-based bioreactor. Perfusion culture of 7 days was successfully achieved with more than 73.8% cells retained in the bioreactor. As expected, the fibres acted as spacers between aggregates, which was evidenced from the enhanced albumin production and more spherical morphology compared with fibre-free packing. In summary, this study shows the advantages of using PDMS-based microwells to form heterotypic aggregates and also demonstrates the feasibility of spacing tissue elements for improving oxygen and nutrient supply to tissue engineering based on modular assembly. (paper)

  14. Extracellular matrix fragmentation in young, healthy cartilaginous tissues.

    Science.gov (United States)

    Craddock, R J; Hodson, N W; Ozols, M; Shearer, T; Hoyland, J A; Sherratt, M J

    2018-02-09

    Although the composition and structure of cartilaginous tissues is complex, collagen II fibrils and aggrecan are the most abundant assemblies in both articular cartilage (AC) and the nucleus pulposus (NP) of the intervertebral disc (IVD). Whilst structural heterogeneity of intact aggrecan ( containing three globular domains) is well characterised, the extent of aggrecan fragmentation in healthy tissues is poorly defined. Using young, yet skeletally mature (18-30 months), bovine AC and NP tissues, it was shown that, whilst the ultrastructure of intact aggrecan was tissue-dependent, most molecules (AC: 95 %; NP: 99.5 %) were fragmented (lacking one or more globular domains). Fragments were significantly smaller and more structurally heterogeneous in the NP compared with the AC (molecular area; AC: 8543 nm2; NP: 4625 nm2; p tissue-invariant. Molecular fragmentation is considered indicative of a pathology; however, these young, skeletally mature tissues were histologically and mechanically (reduced modulus: AC: ≈ 500 kPa; NP: ≈ 80 kPa) comparable to healthy tissues and devoid of notable gelatinase activity (compared with rat dermis). As aggrecan fragmentation was prevalent in neonatal bovine AC (99.5 % fragmented, molecular area: 5137 nm2) as compared with mature AC (95.0 % fragmented, molecular area: 8667 nm2), it was hypothesised that targeted proteolysis might be an adaptive process that modified aggrecan packing (as simulated computationally) and, hence, tissue charge density, mechanical properties and porosity. These observations provided a baseline against which pathological and/or age-related fragmentation of aggrecan could be assessed and suggested that new strategies might be required to engineer constructs that mimic the mechanical properties of native cartilaginous tissues.

  15. Tissue Distribution of a Therapeutic Monoclonal Antibody Determined by Large Pore Microdialysis.

    Science.gov (United States)

    Jadhav, Satyawan B; Khaowroongrueng, Vipada; Fueth, Matthias; Otteneder, Michael B; Richter, Wolfgang; Derendorf, Hartmut

    2017-09-01

    Therapeutic monoclonal antibodies (mAbs) exhibit limited distribution to the target tissues. Determination of target tissue interstitial concentration of mAbs is an important aspect in the assessment of their pharmacokinetic/pharmacodynamics relationship especially for mAbs targeting membrane bound receptors. The pharmacokinetics of R7072, a full length mAb (IgG) targeting human insulin-like growth factor-1 receptor was evaluated following a single intravenous dose at 1, 6.25, and 25 mg/kg in healthy female SCID-beige mice. R7072 showed linear pharmacokinetics over the dose range tested and was characterized by low systemic clearance and long terminal half-life. Furthermore, interstitial distribution of R7072 was evaluated in liver, skin, kidney, and muscle tissues using large pore microdialysis (MD) after intravenous administration of 10 mg/kg dose in mice. The relative recoveries of R7072 were consistent and similar between in vitro and in vivo MD experiments. The tissue and interstitial concentrations were significantly lower compared to serum concentrations and found to be highest in liver and lowest in muscle. The interstitial concentrations of R7072 were approximately 2-fold to 4-fold lower than corresponding total tissue concentrations. Large pore MD appears to be an attractive approach for direct measurement of pharmacologically relevant concentrations of therapeutic mAbs in tissue interstitial fluid. Copyright © 2017 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  16. In Vivo-Like Culture Conditions in a Bioreactor Facilitate Improved Tissue Quality in Corneal Storage.

    Science.gov (United States)

    Schmid, Richard; Tarau, Ioana-Sandra; Rossi, Angela; Leonhardt, Stefan; Schwarz, Thomas; Schuerlein, Sebastian; Lotz, Christian; Hansmann, Jan

    2018-01-01

    The cornea is the most-transplanted tissue worldwide. However, the availability and quality of grafts are limited due to the current methods of corneal storage. In this study, a dynamic bioreactor system is employed to enable the control of intraocular pressure and the culture at the air-liquid interface. Thereby, in vivo-like storage conditions are achieved. Different media combinations for endothelium and epithelium are tested in standard and dynamic conditions to enhance the viability of the tissue. In contrast to culture conditions used in eye banks, the combination of the bioreactor and biochrom medium 1 allows to preserve the corneal endothelium and the epithelium. Assessment of transparency, swelling, and the trans-epithelial-electrical-resistance (TEER) strengthens the impact of the in vivo-like tissue culture. For example, compared to corneas stored under static conditions, significantly lower optical densities and significantly higher TEER values were measured (p-value <0.05). Furthermore, healing of epithelial defects is enabled in the bioreactor, characterized by re-epithelialization and initiated stromal regeneration. Based on the obtained results, an easy-to-use 3D-printed bioreactor composed of only two parts was derived to translate the technology from the laboratory to the eye banks. This optimized bioreactor facilitates noninvasive microscopic monitoring. The improved storage conditions ameliorate the quality of corneal grafts and the storage time in the eye banks to increase availability and reduce re-grafting. © 2017 The Authors. Biotechnology Journal Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  17. Assembly of the CMS hadronic calorimeter

    CERN Multimedia

    Maximilien Brice

    2004-01-01

    The hadronic calorimeter is assembled on the end-cap of the CMS detector in the assembly hall. Hadronic calorimeters measure the energy of particles that interact via the strong force, called hadrons. The detectors are made in a sandwich-like structure where these scintillator tiles are placed between metal sheets.

  18. Thermal infrared images to quantify thermal ablation effects of acid and base on target tissues

    Science.gov (United States)

    Liu, Ran; Wang, Jia; Liu, Jing

    2015-07-01

    Hyperthermia (42-46°C), treatment of tumor tissue through elevated temperature, offers several advantages including high cost-effectiveness, highly targeted ablation and fewer side effects and hence higher safety level over traditional therapies such as chemotherapy and radiotherapy. Recently, hyperthermia using heat release through exothermic acid-base neutralization comes into view owing to its relatively safe products of salt and water and highly confined ablation. However, lack of quantitative understanding of the spatial and temporal temperature profiles that are produced by simultaneous diffusion of liquid chemical and its chemical reaction within tumor tissue impedes the application of this method. This article is dedicated to quantify thermal ablation effects of acid and base both individually and as in neutralization via infrared captured thermal images. A theoretical model is used to approximate specific heat absorption rate (SAR) based on experimental measurements that contrast two types of tissue, normal pork and pig liver. According to the computation, both pork and liver tissue has a higher ability in absorbing hydrochloric acid (HCl) than sodium hydroxide, hence suggesting that a reduced dosage for HCl is appropriate in a surgery. The heating effect depends heavily on the properties of tissue types and amount of chemical reagents administered. Given thermal parameters such as SAR for different tissues, a computational model can be made in predicting temperature transitions which will be helpful in planning and optimizing surgical hyperthermia procedures.

  19. Thermal infrared images to quantify thermal ablation effects of acid and base on target tissues

    Directory of Open Access Journals (Sweden)

    Ran Liu

    2015-07-01

    Full Text Available Hyperthermia (42-46°C, treatment of tumor tissue through elevated temperature, offers several advantages including high cost-effectiveness, highly targeted ablation and fewer side effects and hence higher safety level over traditional therapies such as chemotherapy and radiotherapy. Recently, hyperthermia using heat release through exothermic acid-base neutralization comes into view owing to its relatively safe products of salt and water and highly confined ablation. However, lack of quantitative understanding of the spatial and temporal temperature profiles that are produced by simultaneous diffusion of liquid chemical and its chemical reaction within tumor tissue impedes the application of this method. This article is dedicated to quantify thermal ablation effects of acid and base both individually and as in neutralization via infrared captured thermal images. A theoretical model is used to approximate specific heat absorption rate (SAR based on experimental measurements that contrast two types of tissue, normal pork and pig liver. According to the computation, both pork and liver tissue has a higher ability in absorbing hydrochloric acid (HCl than sodium hydroxide, hence suggesting that a reduced dosage for HCl is appropriate in a surgery. The heating effect depends heavily on the properties of tissue types and amount of chemical reagents administered. Given thermal parameters such as SAR for different tissues, a computational model can be made in predicting temperature transitions which will be helpful in planning and optimizing surgical hyperthermia procedures.

  20. Thermal infrared images to quantify thermal ablation effects of acid and base on target tissues

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ran, E-mail: jliubme@tsinghua.edu.cn, E-mail: liuran@tsinghua.edu.cn; Liu, Jing, E-mail: jliubme@tsinghua.edu.cn, E-mail: liuran@tsinghua.edu.cn [Department of Biomedical Engineering, School of Medicine, Tsinghua University, Beijing 100084 (China); Wang, Jia [Department of Biomedical Engineering, Johns Hopkins University, Baltimore, MD 21218 (United States)

    2015-07-15

    Hyperthermia (42-46°C), treatment of tumor tissue through elevated temperature, offers several advantages including high cost-effectiveness, highly targeted ablation and fewer side effects and hence higher safety level over traditional therapies such as chemotherapy and radiotherapy. Recently, hyperthermia using heat release through exothermic acid-base neutralization comes into view owing to its relatively safe products of salt and water and highly confined ablation. However, lack of quantitative understanding of the spatial and temporal temperature profiles that are produced by simultaneous diffusion of liquid chemical and its chemical reaction within tumor tissue impedes the application of this method. This article is dedicated to quantify thermal ablation effects of acid and base both individually and as in neutralization via infrared captured thermal images. A theoretical model is used to approximate specific heat absorption rate (SAR) based on experimental measurements that contrast two types of tissue, normal pork and pig liver. According to the computation, both pork and liver tissue has a higher ability in absorbing hydrochloric acid (HCl) than sodium hydroxide, hence suggesting that a reduced dosage for HCl is appropriate in a surgery. The heating effect depends heavily on the properties of tissue types and amount of chemical reagents administered. Given thermal parameters such as SAR for different tissues, a computational model can be made in predicting temperature transitions which will be helpful in planning and optimizing surgical hyperthermia procedures.

  1. Automatic detection of multiple UXO-like targets using magnetic anomaly inversion and self-adaptive fuzzy c-means clustering

    Science.gov (United States)

    Yin, Gang; Zhang, Yingtang; Fan, Hongbo; Ren, Guoquan; Li, Zhining

    2017-12-01

    We have developed a method for automatically detecting UXO-like targets based on magnetic anomaly inversion and self-adaptive fuzzy c-means clustering. Magnetic anomaly inversion methods are used to estimate the initial locations of multiple UXO-like sources. Although these initial locations have some errors with respect to the real positions, they form dense clouds around the actual positions of the magnetic sources. Then we use the self-adaptive fuzzy c-means clustering algorithm to cluster these initial locations. The estimated number of cluster centroids represents the number of targets and the cluster centroids are regarded as the locations of magnetic targets. Effectiveness of the method has been demonstrated using synthetic datasets. Computational results show that the proposed method can be applied to the case of several UXO-like targets that are randomly scattered within in a confined, shallow subsurface, volume. A field test was carried out to test the validity of the proposed method and the experimental results show that the prearranged magnets can be detected unambiguously and located precisely.

  2. Size and spatial orientation of uterine tissue transplants on the peritoneum crucially determine the growth and cyst formation of endometriosis-like lesions in mice.

    Science.gov (United States)

    Körbel, Christina; Menger, Michael D; Laschke, Matthias W

    2010-10-01

    In many studies in rodents, intraperitoneal endometriosis-like lesions are surgically induced by syngeneic or autologous transplantation of uterine tissue samples, which are sutured to the abdominal wall. However, until now the surgical techniques have not been standardized, and we address this issue here. Uterine tissue samples were transplanted to the peritoneum of C57BL/6 mice (four study groups, n = 7 each). Using non-invasive high-resolution ultrasound imaging over a period of 4 weeks, we analyzed growth characteristics and cyst formation of the endometriosis-like lesions which developed, in relation to mode of transplantation (syngeneic versus autologous), type of tissue fixed adjacent to the peritoneum (endometrium versus perimetrium), and size of tissue transplanted (2 versus 3 mm). Immunohistochemical analysis was also performed. When the perimetrium, with underlying myometrium, was sutured next to the host peritoneum the endometriosis-like lesions which developed exhibited a higher growth rate (Pendometriosis-like lesions. Our study demonstrates that size and spatial orientation of peritoneally fixed uterine tissue samples crucially determine growth and cyst formation of endometriotic lesions in mice. These findings should improve the standardization and reliability of future studies, performed in the frequently used mouse model of surgically induced endometriosis.

  3. Targeted Delivery of Neutralizing Anti-C5 Antibody to Renal Endothelium Prevents Complement-Dependent Tissue Damage

    Directory of Open Access Journals (Sweden)

    Paolo Durigutto

    2017-09-01

    Full Text Available Complement activation is largely implicated in the pathogenesis of several clinical conditions and its therapeutic neutralization has proven effective in preventing tissue and organ damage. A problem that still needs to be solved in the therapeutic control of complement-mediated diseases is how to avoid side effects associated with chronic neutralization of the complement system, in particular, the increased risk of infections. We addressed this issue developing a strategy based on the preferential delivery of a C5 complement inhibitor to the organ involved in the pathologic process. To this end, we generated Ergidina, a neutralizing recombinant anti-C5 human antibody coupled with a cyclic-RGD peptide, with a distinctive homing property for ischemic endothelial cells and effective in controlling tissue damage in a rat model of renal ischemia/reperfusion injury (IRI. As a result of its preferential localization on renal endothelium, the molecule induced complete inhibition of complement activation at tissue level, and local protection from complement-mediated tissue damage without affecting circulating C5. The ex vivo binding of Ergidina to surgically removed kidney exposed to cold ischemia supports its therapeutic use to prevent posttransplant IRI leading to delay of graft function. Moreover, the finding that the ex vivo binding of Ergidina was not restricted to the kidney, but was also seen on ischemic heart, suggests that this RGD-targeted anti-C5 antibody may represent a useful tool to treat organs prior to transplantation. Based on this evidence, we propose preliminary data showing that Ergidina is a novel targeted drug to prevent complement activation on the endothelium of ischemic kidney.

  4. Toll-like receptor 5 in obesity: the role of gut microbiota and adipose tissue inflammation.

    Science.gov (United States)

    Pekkala, Satu; Munukka, Eveliina; Kong, Lingjia; Pöllänen, Eija; Autio, Reija; Roos, Christophe; Wiklund, Petri; Fischer-Posovszky, Pamela; Wabitsch, Martin; Alen, Markku; Huovinen, Pentti; Cheng, Sulin

    2015-03-01

    This study aimed at establishing bacterial flagellin-recognizing toll-like receptor 5 (TLR5) as a novel link between gut microbiota composition, adipose tissue inflammation, and obesity. An adipose tissue microarray database was used to compare women having the highest (n = 4, H-TLR) and lowest (n = 4, L-TLR) expression levels of TLR5-signaling pathway genes. Gut microbiota composition was profiled using flow cytometry and FISH. Standard laboratory techniques were used to determine anthropometric and clinical variables. In vivo results were verified using cultured human adipocytes. The H-TLR group had higher flagellated Clostridium cluster XIV abundance and Firmicutes-to-Bacteroides ratio. H-TLR subjects had obese phenotype characterized by greater waist circumference, fat %, and blood pressure (P development of obesity through distorted adipose tissue metabolism and inflammation. The in vitro studies in adipocytes show that the underlying mechanisms of the human findings may be due to flagellin-activated TLR5 signaling. © 2015 The Obesity Society.

  5. Draft Genome Sequence of a Picorna-Like Virus Associated with Gill Tissue in Clinically Normal Brook Trout, Salvelinus fontinalis

    OpenAIRE

    Iwanowicz, Luke R.; Iwanowicz, Deborah D.; Adams, Cynthia R.; Galbraith, Heather; Aunins, Aaron; Cornman, Robert S.

    2017-01-01

    ABSTRACT Here, we report a draft genome sequence of a picorna-like virus associated with brook trout, Salvelinus fontinalis, gill tissue. The draft genome comprises 8,681 nucleotides, excluding the poly(A) tract, and contains two open reading frames. It is most similar to picorna-like viruses that infect invertebrates.

  6. Draft Genome Sequence of a Picorna-Like Virus Associated with Gill Tissue in Clinically Normal Brook Trout, Salvelinus fontinalis.

    Science.gov (United States)

    Iwanowicz, Luke R; Iwanowicz, Deborah D; Adams, Cynthia R; Galbraith, Heather; Aunins, Aaron; Cornman, Robert S

    2017-10-12

    Here, we report a draft genome sequence of a picorna-like virus associated with brook trout, Salvelinus fontinalis , gill tissue. The draft genome comprises 8,681 nucleotides, excluding the poly(A) tract, and contains two open reading frames. It is most similar to picorna-like viruses that infect invertebrates.

  7. A novel snowflake-like SnO2 hierarchical architecture with superior gas sensing properties

    Science.gov (United States)

    Li, Yanqiong

    2018-02-01

    Snowflake-like SnO2 hierarchical architecture has been synthesized via a facile hydrothermal method and followed by calcination. The SnO2 hierarchical structures are assembled with thin nanoflakes blocks, which look like snowflake shape. A possible mechanism for the formation of the SnO2 hierarchical structures is speculated. Moreover, gas sensing tests show that the sensor based on snowflake-like SnO2 architectures exhibited excellent gas sensing properties. The enhancement may be attributed to its unique structures, in which the porous feature on the snowflake surface could further increase the active surface area of the materials and provide facile pathways for the target gas.

  8. Targeting hepatic heparin-binding EGF-like growth factor (HB-EGF) induces anti-hyperlipidemia leading to reduction of angiotensin II-induced aneurysm development.

    Science.gov (United States)

    Kim, Seonwook; Yang, Lihua; Kim, Seongu; Lee, Richard G; Graham, Mark J; Berliner, Judith A; Lusis, Aldons J; Cai, Lei; Temel, Ryan E; Rateri, Debra L; Lee, Sangderk

    2017-01-01

    The upregulated expression of heparin binding EGF-like growth factor (HB-EGF) in the vessel and circulation is associated with risk of cardiovascular disease. In this study, we tested the effects of HB-EGF targeting using HB-EGF-specific antisense oligonucleotide (ASO) on the development of aortic aneurysm in a mouse aneurysm model. Low-density lipoprotein receptor (LDLR) deficient mice (male, 16 weeks of age) were injected with control and HB-EGF ASOs for 10 weeks. To induce aneurysm, the mice were fed a high fat diet (22% fat, 0.2% cholesterol; w/w) at 5 week point of ASO administration and infused with angiotensin II (AngII, 1,000ng/kg/min) for the last 4 weeks of ASO administration. We confirmed that the HB-EGF ASO administration significantly downregulated HB-EGF expression in multiple tissues including the liver. Importantly, the HB-EGF ASO administration significantly suppressed development of aortic aneurysms including thoracic and abdominal types. Interestingly, the HB-EGF ASO administration induced a remarkable anti-hyperlipidemic effect by suppressing very low density lipoprotein (VLDL) level in the blood. Mechanistically, the HB-EGF targeting suppressed hepatic VLDL secretion rate without changing heparin-releasable plasma triglyceride (TG) hydrolytic activity or fecal neutral cholesterol excretion rate. This result suggested that the HB-EGF targeting induced protection against aneurysm development through anti-hyperlipidemic effects. Suppression of hepatic VLDL production process appears to be a key mechanism for the anti-hyperlipidemic effects by the HB-EGF targeting.

  9. Plasma membrane is the site of productive HIV-1 particle assembly.

    Directory of Open Access Journals (Sweden)

    Nolwenn Jouvenet

    2006-12-01

    Full Text Available Recently proposed models that have gained wide acceptance posit that HIV-1 virion morphogenesis is initiated by targeting the major structural protein (Gag to late endosomal membranes. Thereafter, late endosome-based secretory pathways are thought to deliver Gag or assembled virions to the plasma membrane (PM and extracellular milieu. We present several findings that are inconsistent with this model. Specifically, we demonstrate that HIV-1 Gag is delivered to the PM, and virions are efficiently released into the extracellular medium, when late endosome motility is abolished. Furthermore, we show that HIV-1 virions are efficiently released when assembly is rationally targeted to the PM, but not when targeted to late endosomes. Recently synthesized Gag first accumulates and assembles at the PM, but a proportion is subsequently internalized via endocytosis or phagocytosis, thus accounting for observations of endosomal localization. We conclude that HIV-1 assembly is initiated and completed at the PM, and not at endosomal membranes.

  10. Metabolic analysis of radioresistant medulloblastoma stem-like clones and potential therapeutic targets.

    Directory of Open Access Journals (Sweden)

    Lue Sun

    Full Text Available Medulloblastoma is a fatal brain tumor in children, primarily due to the presence of treatment-resistant medulloblastoma stem cells. The energy metabolic pathway is a potential target of cancer therapy because it is often different between cancer cells and normal cells. However, the metabolic properties of medulloblastoma stem cells, and whether specific metabolic pathways are essential for sustaining their stem cell-like phenotype and radioresistance, remain unclear. We have established radioresistant medulloblastoma stem-like clones (rMSLCs by irradiation of the human medulloblastoma cell line ONS-76. Here, we assessed reactive oxygen species (ROS production, mitochondria function, oxygen consumption rate (OCR, energy state, and metabolites of glycolysis and tricarboxylic acid cycle in rMSLCs and parental cells. rMSLCs showed higher lactate production and lower oxygen consumption rate than parental cells. Additionally, rMSLCs had low mitochondria mass, low endogenous ROS production, and existed in a low-energy state. Treatment with the metabolic modifier dichloroacetate (DCA resulted in mitochondria dysfunction, glycolysis inhibition, elongated mitochondria morphology, and increased ROS production. DCA also increased radiosensitivity by suppression of the DNA repair capacity through nuclear oxidization and accelerated the generation of acetyl CoA to compensate for the lack of ATP. Moreover, treatment with DCA decreased cancer stem cell-like characters (e.g., CD133 positivity and sphere-forming ability in rMSLCs. Together, our findings provide insights into the specific metabolism of rMSLCs and illuminate potential metabolic targets that might be exploited for therapeutic benefit in medulloblastoma.

  11. De novo assembly and transcriptome analysis of five major tissues of Jatropha curcas L. using GS FLX titanium platform of 454 pyrosequencing

    Directory of Open Access Journals (Sweden)

    Parani Madasamy

    2011-04-01

    Full Text Available Abstract Background Jatropha curcas L. is an important non-edible oilseed crop with promising future in biodiesel production. However, factors like oil yield, oil composition, toxic compounds in oil cake, pests and diseases limit its commercial potential. Well established genetic engineering methods using cloned genes could be used to address these limitations. Earlier, 10,983 unigenes from Sanger sequencing of ESTs, and 3,484 unique assembled transcripts from 454 pyrosequencing of uncloned cDNAs were reported. In order to expedite the process of gene discovery, we have undertaken 454 pyrosequencing of normalized cDNAs prepared from roots, mature leaves, flowers, developing seeds, and embryos of J. curcas. Results From 383,918 raw reads, we obtained 381,957 quality-filtered and trimmed reads that are suitable for the assembly of transcript sequences. De novo contig assembly of these reads generated 17,457 assembled transcripts (contigs and 54,002 singletons. Average length of the assembled transcripts was 916 bp. About 30% of the transcripts were longer than 1000 bases, and the size of the longest transcript was 7,173 bases. BLASTX analysis revealed that 2,589 of these transcripts are full-length. The assembled transcripts were validated by RT-PCR analysis of 28 transcripts. The results showed that the transcripts were correctly assembled and represent actively expressed genes. KEGG pathway mapping showed that 2,320 transcripts are related to major biochemical pathways including the oil biosynthesis pathway. Overall, the current study reports 14,327 new assembled transcripts which included 2589 full-length transcripts and 27 transcripts that are directly involved in oil biosynthesis. Conclusion The large number of transcripts reported in the current study together with existing ESTs and transcript sequences will serve as an invaluable genetic resource for crop improvement in jatropha. Sequence information of those genes that are involved in oil

  12. De novo assembly and transcriptome analysis of five major tissues of Jatropha curcas L. using GS FLX titanium platform of 454 pyrosequencing.

    Science.gov (United States)

    Natarajan, Purushothaman; Parani, Madasamy

    2011-04-15

    Jatropha curcas L. is an important non-edible oilseed crop with promising future in biodiesel production. However, factors like oil yield, oil composition, toxic compounds in oil cake, pests and diseases limit its commercial potential. Well established genetic engineering methods using cloned genes could be used to address these limitations. Earlier, 10,983 unigenes from Sanger sequencing of ESTs, and 3,484 unique assembled transcripts from 454 pyrosequencing of uncloned cDNAs were reported. In order to expedite the process of gene discovery, we have undertaken 454 pyrosequencing of normalized cDNAs prepared from roots, mature leaves, flowers, developing seeds, and embryos of J. curcas. From 383,918 raw reads, we obtained 381,957 quality-filtered and trimmed reads that are suitable for the assembly of transcript sequences. De novo contig assembly of these reads generated 17,457 assembled transcripts (contigs) and 54,002 singletons. Average length of the assembled transcripts was 916 bp. About 30% of the transcripts were longer than 1000 bases, and the size of the longest transcript was 7,173 bases. BLASTX analysis revealed that 2,589 of these transcripts are full-length. The assembled transcripts were validated by RT-PCR analysis of 28 transcripts. The results showed that the transcripts were correctly assembled and represent actively expressed genes. KEGG pathway mapping showed that 2,320 transcripts are related to major biochemical pathways including the oil biosynthesis pathway. Overall, the current study reports 14,327 new assembled transcripts which included 2589 full-length transcripts and 27 transcripts that are directly involved in oil biosynthesis. The large number of transcripts reported in the current study together with existing ESTs and transcript sequences will serve as an invaluable genetic resource for crop improvement in jatropha. Sequence information of those genes that are involved in oil biosynthesis could be used for metabolic engineering of

  13. A Novel bioreactor with mechanical stimulation for skeletal tissue engineering

    Directory of Open Access Journals (Sweden)

    M. Petrović

    2009-01-01

    Full Text Available The provision of mechanical stimulation is believed to be necessary for the functional assembly of skeletal tissues, which are normally exposed to a variety of biomechanical signals in vivo. In this paper, we present a development and validation of a novel bioreactor aimed for skeletal tissue engineering that provides dynamic compression and perfusion of cultivated tissues. Dynamic compression can be applied at frequencies up to 67.5 Hz and displacements down to 5 m thus suitable for the simulation of physiological conditions in a native cartilage tissue (0.1-1 Hz, 5-10 % strain. The bioreactor also includes a load sensor that was calibrated so to measure average loads imposed on tissue samples. Regimes of the mechanical stimulation and acquisition of load sensor outputs are directed by an automatic control system using applications developed within the LabView platform. In addition, perfusion of tissue samples at physiological velocities (10–100 m/s provides efficient mass transfer, as well as the possibilities to expose the cells to hydrodynamic shear and simulate the conditions in a native bone tissue. Thus, the novel bioreactor is suited for studies of the effects of different biomechanical signals on in vitro regeneration of skeletal tissues, as well as for the studies of newly formulated biomaterials and cell biomaterial interactions under in vivo-like settings.

  14. Detection of a Usp-like gene in Calotropis procera plant from the de novo assembled genome contigs of the high-throughput sequencing dataset

    KAUST Repository

    Shokry, Ahmed M.

    2014-02-01

    The wild plant species Calotropis procera (C. procera) has many potential applications and beneficial uses in medicine, industry and ornamental field. It also represents an excellent source of genes for drought and salt tolerance. Genes encoding proteins that contain the conserved universal stress protein (USP) domain are known to provide organisms like bacteria, archaea, fungi, protozoa and plants with the ability to respond to a plethora of environmental stresses. However, information on the possible occurrence of Usp in C. procera is not available. In this study, we uncovered and characterized a one-class A Usp-like (UspA-like, NCBI accession No. KC954274) gene in this medicinal plant from the de novo assembled genome contigs of the high-throughput sequencing dataset. A number of GenBank accessions for Usp sequences were blasted with the recovered de novo assembled contigs. Homology modelling of the deduced amino acids (NCBI accession No. AGT02387) was further carried out using Swiss-Model, accessible via the EXPASY. Superimposition of C. procera USPA-like full sequence model on Thermus thermophilus USP UniProt protein (PDB accession No. Q5SJV7) was constructed using RasMol and Deep-View programs. The functional domains of the novel USPA-like amino acids sequence were identified from the NCBI conserved domain database (CDD) that provide insights into sequence structure/function relationships, as well as domain models imported from a number of external source databases (Pfam, SMART, COG, PRK, TIGRFAM). © 2014 Académie des sciences.

  15. Target tissue influences on cholinergic development of parasympathetic motor neurons

    International Nuclear Information System (INIS)

    Tuttle, J.B.; Pilar, G.

    1986-01-01

    The normal function of neurons in the nervous system depends upon the orderly formation and maintenance of appropriate connections with other neurons and with non-neural target tissues. Having formed an appropriate synapse, the authors attempt to find how the interaction influences the subsequent program of neuronal differentiation and survival. The studies were made on neurons from the avian ciliary ganglion and their terminals in the iris. Concomitantly in time with the shift from an embryonic, fatiguable junction to the mature, more secure transmission, there is a large change in the capacity for ACh synthesis measured using radiolableled substrate. Only at this point in development does one detect and increase in the amount of tritium-ACh synthesized from tritium-choline in response to a pre-conditioning depolarization. The studies of development in vivo have provided a description of the steps taking place during maturation of a neuromuscular junction

  16. Thermosensitive Self-Assembling Block Copolymers as Drug Delivery Systems

    Directory of Open Access Journals (Sweden)

    Giovanni Filippo Palmieri

    2011-04-01

    Full Text Available Self-assembling block copolymers (poloxamers, PEG/PLA and PEG/PLGA diblock and triblock copolymers, PEG/polycaprolactone, polyether modified poly(Acrylic Acid with large solubility difference between hydrophilic and hydrophobic moieties have the property of forming temperature dependent micellar aggregates and, after a further temperature increase, of gellifying due to micelle aggregation or packing. This property enables drugs to be mixed in the sol state at room temperature then the solution can be injected into a target tissue, forming a gel depot in-situ at body temperature with the goal of providing drug release control. The presence of micellar structures that give rise to thermoreversible gels, characterized by low toxicity and mucomimetic properties, makes this delivery system capable of solubilizing water-insoluble or poorly soluble drugs and of protecting labile molecules such as proteins and peptide drugs.

  17. Targeted Sterically Stabilized Phospholipid siRNA Nanomedicine for Hepatic and Renal Fibrosis

    Directory of Open Access Journals (Sweden)

    Fatima Khaja

    2016-01-01

    Full Text Available Since its discovery, small interfering RNA (siRNA has been considered a potent tool for modulating gene expression. It has the ability to specifically target proteins via selective degradation of messenger RNA (mRNA not easily accessed by conventional drugs. Hence, RNA interference (RNAi therapeutics have great potential in the treatment of many diseases caused by faulty protein expression such as fibrosis and cancer. However, for clinical application siRNA faces a number of obstacles, such as poor in vivo stability, and off-target effects. Here we developed a unique targeted nanomedicine to tackle current siRNA delivery issues by formulating a biocompatible, biodegradable and relatively inexpensive nanocarrier of sterically stabilized phospholipid nanoparticles (SSLNPs. This nanocarrier is capable of incorporating siRNA in its core through self-association with a novel cationic lipid composed of naturally occuring phospholipids and amino acids. This overall assembly protects and delivers sufficient amounts of siRNA to knockdown over-expressed protein in target cells. The siRNA used in this study, targets connective tissue growth factor (CTGF, an important regulator of fibrosis in both hepatic and renal cells. Furthermore, asialoglycoprotein receptors are targeted by attaching the galactosamine ligand to the nanocarries which enhances the uptake of nanoparticles by hepatocytes and renal tubular epithelial cells, the major producers of CTGF in fibrosis. On animals this innovative nanoconstruct, small interfering RNA in sterically stabilized phospholipid nanoparticles (siRNA-SSLNP, showed favorable pharmacokinetic properties and accumulated mostly in hepatic and renal tissues making siRNA-SSLNP a suitable system for targeting liver and kidney fibrotic diseases.

  18. Supracolloidal Assemblies as Sacrificial Templates for Porous Silk-Based Biomaterials

    Directory of Open Access Journals (Sweden)

    John G. Hardy

    2015-08-01

    Full Text Available Tissues in the body are hierarchically structured composite materials with tissue-specific properties. Urea self-assembles via hydrogen bonding interactions into crystalline supracolloidal assemblies that can be used to impart macroscopic pores to polymer-based tissue scaffolds. In this communication, we explain the solvent interactions governing the solubility of urea and thereby the scope of compatible polymers. We also highlight the role of solvent interactions on the morphology of the resulting supracolloidal crystals. We elucidate the role of polymer-urea interactions on the morphology of the pores in the resulting biomaterials. Finally, we demonstrate that it is possible to use our urea templating methodology to prepare Bombyx mori silk protein-based biomaterials with pores that human dermal fibroblasts respond to by aligning with the long axis of the pores. This methodology has potential for application in a variety of different tissue engineering niches in which cell alignment is observed, including skin, bone, muscle and nerve.

  19. Dual Targeting of the Insulin-Like Growth Factor and Collateral Pathways in Cancer: Combating Drug Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Ludwig, Joseph A., E-mail: jaludwig@mdanderson.org; Lamhamedi-Cherradi, Salah-Eddine [Departments of Sarcoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Lee, Ho-Young [Departments of Thoracic Head & Neck Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Naing, Aung [Investigational Cancer Therapeutics, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Benjamin, Robert [Departments of Sarcoma Medical Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States)

    2011-07-26

    The insulin-like growth factor pathway, regulated by a complex interplay of growth factors, cognate receptors, and binding proteins, is critically important for many of the hallmarks of cancer such as oncogenesis, cell division, growth, and antineoplastic resistance. Naturally, a number of clinical trials have sought to directly abrogate insulin-like growth factor receptor 1 (IGF-1R) function and/or indirectly mitigate its downstream mediators such as mTOR, PI3K, MAPK, and others under the assumption that such therapeutic interventions would provide clinical benefit, demonstrable by impaired tumor growth as well as prolonged progression-free and overall survival for patients. Though a small subset of patients enrolled within phase I or II clinical trials revealed dramatic clinical response to IGF-1R targeted therapies (most using monoclonal antibodies to IGF-1R), in toto, the anticancer effect has been underwhelming and unsustained, as even those with marked clinical responses seem to rapidly acquire resistance to IGF-1R targeted agents when used alone through yet to be identified mechanisms. As the IGF-1R receptor is just one of many that converge upon common intracellular signaling cascades, it is likely that effective IGF-1R targeting must occur in parallel with blockade of redundant signaling paths. Herein, we present the rationale for dual targeting of IGF-1R and other signaling molecules as an effective strategy to combat acquired drug resistance by carcinomas and sarcomas.

  20. Dual Targeting of the Insulin-Like Growth Factor and Collateral Pathways in Cancer: Combating Drug Resistance

    International Nuclear Information System (INIS)

    Ludwig, Joseph A.; Lamhamedi-Cherradi, Salah-Eddine; Lee, Ho-Young; Naing, Aung; Benjamin, Robert

    2011-01-01

    The insulin-like growth factor pathway, regulated by a complex interplay of growth factors, cognate receptors, and binding proteins, is critically important for many of the hallmarks of cancer such as oncogenesis, cell division, growth, and antineoplastic resistance. Naturally, a number of clinical trials have sought to directly abrogate insulin-like growth factor receptor 1 (IGF-1R) function and/or indirectly mitigate its downstream mediators such as mTOR, PI3K, MAPK, and others under the assumption that such therapeutic interventions would provide clinical benefit, demonstrable by impaired tumor growth as well as prolonged progression-free and overall survival for patients. Though a small subset of patients enrolled within phase I or II clinical trials revealed dramatic clinical response to IGF-1R targeted therapies (most using monoclonal antibodies to IGF-1R), in toto, the anticancer effect has been underwhelming and unsustained, as even those with marked clinical responses seem to rapidly acquire resistance to IGF-1R targeted agents when used alone through yet to be identified mechanisms. As the IGF-1R receptor is just one of many that converge upon common intracellular signaling cascades, it is likely that effective IGF-1R targeting must occur in parallel with blockade of redundant signaling paths. Herein, we present the rationale for dual targeting of IGF-1R and other signaling molecules as an effective strategy to combat acquired drug resistance by carcinomas and sarcomas

  1. Dual Targeting of the Insulin-Like Growth Factor and Collateral Pathways in Cancer: Combating Drug Resistance

    Directory of Open Access Journals (Sweden)

    Aung Naing

    2011-07-01

    Full Text Available The insulin-like growth factor pathway, regulated by a complex interplay of growth factors, cognate receptors, and binding proteins, is critically important for many of the hallmarks of cancer such as oncogenesis, cell division, growth, and antineoplastic resistance. Naturally, a number of clinical trials have sought to directly abrogate insulin-like growth factor receptor 1 (IGF-1R function and/or indirectly mitigate its downstream mediators such as mTOR, PI3K, MAPK, and others under the assumption that such therapeutic interventions would provide clinical benefit, demonstrable by impaired tumor growth as well as prolonged progression-free and overall survival for patients. Though a small subset of patients enrolled within phase I or II clinical trials revealed dramatic clinical response to IGF-1R targeted therapies (most using monoclonal antibodies to IGF-1R, in toto, the anticancer effect has been underwhelming and unsustained, as even those with marked clinical responses seem to rapidly acquire resistance to IGF-1R targeted agents when used alone through yet to be identified mechanisms. As the IGF-1R receptor is just one of many that converge upon common intracellular signaling cascades, it is likely that effective IGF-1R targeting must occur in parallel with blockade of redundant signaling paths. Herein, we present the rationale for dual targeting of IGF-1R and other signaling molecules as an effective strategy to combat acquired drug resistance by carcinomas and sarcomas.

  2. De novo Transcriptome Assembly of Common Wild Rice (Oryza rufipogon Griff.) and Discovery of Drought-Response Genes in Root Tissue Based on Transcriptomic Data.

    Science.gov (United States)

    Tian, Xin-Jie; Long, Yan; Wang, Jiao; Zhang, Jing-Wen; Wang, Yan-Yan; Li, Wei-Min; Peng, Yu-Fa; Yuan, Qian-Hua; Pei, Xin-Wu

    2015-01-01

    The perennial O. rufipogon (common wild rice), which is considered to be the ancestor of Asian cultivated rice species, contains many useful genetic resources, including drought resistance genes. However, few studies have identified the drought resistance and tissue-specific genes in common wild rice. In this study, transcriptome sequencing libraries were constructed, including drought-treated roots (DR) and control leaves (CL) and roots (CR). Using Illumina sequencing technology, we generated 16.75 million bases of high-quality sequence data for common wild rice and conducted de novo assembly and annotation of genes without prior genome information. These reads were assembled into 119,332 unigenes with an average length of 715 bp. A total of 88,813 distinct sequences (74.42% of unigenes) significantly matched known genes in the NCBI NT database. Differentially expressed gene (DEG) analysis showed that 3617 genes were up-regulated and 4171 genes were down-regulated in the CR library compared with the CL library. Among the DEGs, 535 genes were expressed in roots but not in shoots. A similar comparison between the DR and CR libraries showed that 1393 genes were up-regulated and 315 genes were down-regulated in the DR library compared with the CR library. Finally, 37 genes that were specifically expressed in roots were screened after comparing the DEGs identified in the above-described analyses. This study provides a transcriptome sequence resource for common wild rice plants and establishes a digital gene expression profile of wild rice plants under drought conditions using the assembled transcriptome data as a reference. Several tissue-specific and drought-stress-related candidate genes were identified, representing a fully characterized transcriptome and providing a valuable resource for genetic and genomic studies in plants.

  3. Lysyl oxidase‑like 2 is expressed in kidney tissue and is associated with the progression of tubulointerstitial fibrosis.

    Science.gov (United States)

    Choi, Sung-Eun; Jeon, Nara; Choi, Hoon Young; Shin, Jae Il; Jeong, Hyeon Joo; Lim, Beom Jin

    2017-09-01

    Tubulointerstitial fibrosis is a common end point of chronic kidney diseases, and preventing its progression is key to avoiding renal failure. Transforming growth factor‑β (TGF‑β) and associated molecules promote tubulointerstitial fibrosis; however, effective therapies targeting these molecules have yet to be developed. Lysyl oxidase‑like 2 (LOXL2), which is involved in invasive growth and metastasis of malignant neoplasms, has recently been reported to serve a key role in hepatic and pulmonary fibrosis. However, little is currently known regarding LOXL2 expression in the kidney and its involvement in tubulointerstitial fibrosis. The present study evaluated LOXL2 expression in human and mouse kidney tissues, as well as in cultured renal cells. LOXL2 protein expression was detected in glomerular capillary loops and tubular epithelial cells in human and mouse kidneys. Glomerular LOXL2 was localized to the cytoplasm of podocytes, as determined by double immunofluorescence microscopy using a podocyte marker (synaptopodin). This result was supported by western blot analysis, which demonstrated that LOXL2 protein expression is present in cultured human podocytes and HK‑2 human proximal tubular cells. In addition, the mRNA and protein expression levels of LOXL2 were higher in a mouse model of tubulointerstitial fibrosis compared with in control mice. In addition, immunohistochemistry results demonstrated that LOXL2 is present in the fibrous interstitium and infiltrating mononuclear cells in a mouse model of tubulointerstitial fibrosis. The present study demonstrated that LOXL2 is expressed in compartments of renal tissue, where it appears to contribute to the progression of tubulointerstitial fibrosis.

  4. Matrix metalloprotease-3 expression in the medial plica and pannus-like tissue in knees from patients with medial compartment osteoarthritis.

    Science.gov (United States)

    Wang, Hwai-Shi; Kuo, Pei-Yin; Yang, Chih-Chang; Lyu, Shaw-Ruey

    2011-03-01

    The severity of cartilage degeneration is positively correlated with the severity of the pathologic change of medial plica. However, knowledge of the pathogenic mechanisms and the impact of plica on cartilage destruction is limited. The aim of the present study was therefore to investigate matrix metalloprotease-3 (MMP-3) expression in the plica isolated from patients with medial compartment osteoarthritis of the knee. Immunohistochemistry showed that MMP-3 was highly expressed in pannus-like tissue and the plica. Western blotting of culture supernatants showed that interleukin-1β (IL-1β) treatment induced MMP-3 release by cells isolated from pannus tissue or the plica. Furthermore, reverse transcriptase polymerase chain reaction and real-time polymerase chain reaction analysis showed that MMP-3 mRNA levels were increased after IL-1β treatment of the cultured cells. MMP-3 and IL-1β mRNAs were expressed in the plica and pannus-like tissue, with MMP-3 mRNA being expressed at significantly higher levels in the plica than in normal synovial membrane and highly expressed in the plica at different stages in osteoarthritis (OA) patients. Pannus-like tissue and the plica express IL-1β and MMP-3. Moreover, MMP-3 mRNA and protein expression in the plica may contribute to the pathogenesis of OA. © 2011 Blackwell Publishing Limited.

  5. Syntactic sequencing in Hebbian cell assemblies.

    Science.gov (United States)

    Wennekers, Thomas; Palm, Günther

    2009-12-01

    Hebbian cell assemblies provide a theoretical framework for the modeling of cognitive processes that grounds them in the underlying physiological neural circuits. Recently we have presented an extension of cell assemblies by operational components which allows to model aspects of language, rules, and complex behaviour. In the present work we study the generation of syntactic sequences using operational cell assemblies timed by unspecific trigger signals. Syntactic patterns are implemented in terms of hetero-associative transition graphs in attractor networks which cause a directed flow of activity through the neural state space. We provide regimes for parameters that enable an unspecific excitatory control signal to switch reliably between attractors in accordance with the implemented syntactic rules. If several target attractors are possible in a given state, noise in the system in conjunction with a winner-takes-all mechanism can randomly choose a target. Disambiguation can also be guided by context signals or specific additional external signals. Given a permanently elevated level of external excitation the model can enter an autonomous mode, where it generates temporal grammatical patterns continuously.

  6. Regulatory aspects of tissue donation, banking and transplantation in India.

    Science.gov (United States)

    Lobo Gajiwala, Astrid

    2018-05-04

    Amendments to India's Transplantation of Human Organs Act, 1994, have established the legality of tissue donation and transplantation from deceased donors and the conditions under which they are permitted. The amended Act, now known as The Transplantation of Human Organs and Tissues Act, 1994, seeks to prevent the commercialization of tissue donation and to guarantee the safety of indigenous allografts. Registration of tissue banks, compliance with national standards and the appointment of transplant co-ordinators in hospitals registered under the Act are now mandatory. A national registry and Regional and State networks for donation and transplantation of tissues have been introduced. Despite the amendments a few anomalies of the principal Act persist as some of the differences between tissue and organ donation and transplantation have been overlooked. These include the possibility of skin donation in locations other than hospitals; the donation of medical and surgical tissue residues which does not pose any risk to the living donor; the non-requirement for compatibility between donor and recipient; the delayed time factor between tissue donation and transplantation which makes identification of a recipient at the time of donation impossible; and the easy availability of alternatives to tissues which make waiting lists redundant for many tissues. Rules for the implementation of the amended Act were framed in 2014 but like the Act must be adopted by the State health assemblies to become universally applicable in the country.

  7. Stem Cells from Cryopreserved Human Dental Pulp Tissues Sequentially Differentiate into Definitive Endoderm and Hepatocyte-Like Cells in vitro.

    Science.gov (United States)

    Han, Young-Jin; Kang, Young-Hoon; Shivakumar, Sarath Belame; Bharti, Dinesh; Son, Young-Bum; Choi, Yong-Ho; Park, Won-Uk; Byun, June-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-01-01

    We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro . Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro , the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro . Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering.

  8. Giant reversible magnetocaloric effect in flower-like β-Co(OH){sub 2} hierarchical superstructures self-assembled by nanosheets

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Xianguo; Feng, Chao; Xiao, Feng; Jin, Chuangui; Xia, Ailin, E-mail: liuxianguohugh@gmail.com, E-mail: eeswor@polyu.edu.hk [Anhui Key Laboratory of Metal Materials and Processing, School of Materials Science and Engineering, Anhui University of Technology, Ma' anshan, PR (China); Or, Siu Wing [Department of Electrical Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon (Hong Kong); Sun, Yuping [Center for Engineering Practice and Innovation Education, Anhui University of Technology, Ma' anshan, PR (China)

    2014-01-15

    A facile hydrothermal strategy is proposed to synthesize flower-like β- Co(OH){sub 2} hierarchical microspherical superstructures with a diameter of 0.5-1.5 µm, which are self-assembled by β - Co(OH){sub 2} nano sheets with the average thickness ranging between 20 and 40 nm. The magnetocaloric effect associated with magnetic phase transitions in Co(OH){sub 2} superstructures has been investigated. A sign change in the magnetocaloric effect is induced by a magnetic field, which is related to a filed-induced transition from the antiferromagnetic to the ferromagnetic state below the Néel temperature. The large reversible magnetic-entropy change –ΔS{sub m} (13.4 J/kg K at 15 K for a field change of 5 T) indicates that flower-like Co(OH){sub 2} superstructures is a potential candidate for application in magnetic refrigeration in the low-temperature range. (author)

  9. Targeting Adipose Tissue Lipid Metabolism to Improve Glucose Metabolism in Cardiometabolic Disease

    Directory of Open Access Journals (Sweden)

    Johan W.E. Jocken

    2014-10-01

    Full Text Available With Type 2 diabetes mellitus and cardiovascular disease prevalence on the rise, there is a growing need for improved strategies to prevent or treat obesity and insulin resistance, both of which are major risk factors for these chronic diseases. Impairments in adipose tissue lipid metabolism seem to play a critical role in these disorders. In the classical picture of intracellular lipid breakdown, cytosolic lipolysis was proposed as the sole mechanism for triacylglycerol hydrolysis in adipocytes. Recent evidence suggests involvement of several hormones, membrane receptors, and intracellular signalling cascades, which has added complexity to the regulation of cytosolic lipolysis. Interestingly, a specific form of autophagy, called lipophagy, has been implicated as alternative lipolytic pathway. Defective regulation of cytosolic lipolysis and lipophagy might have substantial effects on lipid metabolism, thereby contributing to adipose tissue dysfunction, insulin resistance, and related cardiometabolic (cMet diseases. This review will discuss recent advances in our understanding of classical lipolysis and lipophagy in adipocyte lipid metabolism under normal and pathological conditions. Furthermore, the question of whether modulation of adipocyte lipolysis and lipophagy might be a potential therapeutic target to combat cMet disorders will be addressed.

  10. Target cells in internal dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Goessner, W

    2003-07-01

    Data related to radium induced bone sarcomas in humans are used as a model for defining target cells on bone surfaces and in the bone marrow. The differential distribution of radiation induced bone sarcoma types with a high ratio of non-bone producing, mainly fibroblastic tumours, challenges the ICRP concept that the bone lining cells are target cells. Multipotential mesenchymal stem cells are located within the range of alpha particles, and are the most likely target cells for the fibroblastic type of bone sarcoma. The histogenesis of bone sarcomas after irradiation with alpha emitters shows that their final histopathology is not dependent on a single target cell. Each target cell has a microenvironment, which has to be regarded as a synergistic morpho-functional tissue unit. For this the concept of 'histion', a term used in general pathology, is proposed. Interactions between target cells that have been hit by alpha-particles, leading to lethal, mutational or transformation events with all components of a 'histion', will prove critical to understanding the pathogenesis of both deterministic and stochastic late effects. (author)

  11. Target cells in internal dosimetry

    International Nuclear Information System (INIS)

    Goessner, W.

    2003-01-01

    Data related to radium induced bone sarcomas in humans are used as a model for defining target cells on bone surfaces and in the bone marrow. The differential distribution of radiation induced bone sarcoma types with a high ratio of non-bone producing, mainly fibroblastic tumours, challenges the ICRP concept that the bone lining cells are target cells. Multipotential mesenchymal stem cells are located within the range of alpha particles, and are the most likely target cells for the fibroblastic type of bone sarcoma. The histogenesis of bone sarcomas after irradiation with alpha emitters shows that their final histopathology is not dependent on a single target cell. Each target cell has a microenvironment, which has to be regarded as a synergistic morpho-functional tissue unit. For this the concept of 'histion', a term used in general pathology, is proposed. Interactions between target cells that have been hit by alpha-particles, leading to lethal, mutational or transformation events with all components of a 'histion', will prove critical to understanding the pathogenesis of both deterministic and stochastic late effects. (author)

  12. The accumulation of assembly intermediates of the mitochondrial complex I matrix arm is reduced by limiting glucose uptake in a neuronal-like model of MELAS syndrome.

    Science.gov (United States)

    Geffroy, Guillaume; Benyahia, Rayane; Frey, Samuel; Desquiret-Dumas, Valerie; Gueguen, Naig; Bris, Celine; Belal, Sophie; Inisan, Aurore; Renaud, Aurelie; Chevrollier, Arnaud; Henrion, Daniel; Bonneau, Dominique; Letournel, Franck; Lenaers, Guy; Reynier, Pascal; Procaccio, Vincent

    2018-05-01

    Ketogenic diet (KD) which combined carbohydrate restriction and the addition of ketone bodies has emerged as an alternative metabolic intervention used as an anticonvulsant therapy or to treat different types of neurological or mitochondrial disorders including MELAS syndrome. MELAS syndrome is a severe mitochondrial disease mainly due to the m.3243A > G mitochondrial DNA mutation. The broad success of KD is due to multiple beneficial mechanisms with distinct effects of very low carbohydrates and ketones. To evaluate the metabolic part of carbohydrate restriction, transmitochondrial neuronal-like cybrid cells carrying the m.3243A > G mutation, shown to be associated with a severe complex I deficiency was exposed during 3 weeks to glucose restriction. Mitochondrial enzyme defects were combined with an accumulation of complex I (CI) matrix intermediates in the untreated mutant cells, leading to a drastic reduction in CI driven respiration. The severe reduction of CI was also paralleled in post-mortem brain tissue of a MELAS patient carrying high mutant load. Importantly, lowering significantly glucose concentration in cell culture improved CI assembly with a significant reduction of matrix assembly intermediates and respiration capacities were restored in a sequential manner. In addition, OXPHOS protein expression and mitochondrial DNA copy number were significantly increased in mutant cells exposed to glucose restriction. The accumulation of CI matrix intermediates appeared as a hallmark of MELAS pathophysiology highlighting a critical pathophysiological mechanism involving CI disassembly, which can be alleviated by lowering glucose fuelling and the induction of mitochondrial biogenesis, emphasizing the usefulness of metabolic interventions in MELAS syndrome. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Targeting an Oncolytic Influenza A Virus to Tumor Tissue by Elastase

    Directory of Open Access Journals (Sweden)

    Irina Kuznetsova

    2017-12-01

    Full Text Available Oncolytic viruses are currently established as a novel type of immunotherapy. The challenge is to safely target oncolytic viruses to tumors. Previously, we have generated influenza A viruses (IAVs containing deletions in the viral interferon antagonist. Those deletions have attenuated the virus in normal tissue but allowed replication in tumor cells. IAV entry is mediated by hemagglutinin (HA, which needs to be activated by a serine protease, for example, through trypsin. To further target the IAV to tumors, we have changed the trypsin cleavage site to an elastase cleavage site. We chose this cleavage site because elastase is expressed in the tumor microenvironment. Moreover, the exchange of the cleavage site previously has been shown to attenuate viral growth in lungs. Newly generated elastase-activated influenza viruses (AE viruses grew to similar titers in tumor cells as the trypsin-activated counterparts (AT viruses. Intratumoral injection of AE viruses into syngeneic B16f1 melanoma-derived tumors in mice reduced tumor growth similar to AT viruses and had a better therapeutic effect in heterologous human PANC-1-derived tumors. Therefore, the introduction of the attenuation marker “elastase cleavage site” in viral HA allows for safe, effective oncolytic virus therapy.

  14. Matrix development in self-assembly of articular cartilage.

    Directory of Open Access Journals (Sweden)

    Gidon Ofek

    2008-07-01

    Full Text Available Articular cartilage is a highly functional tissue which covers the ends of long bones and serves to ensure proper joint movement. A tissue engineering approach that recapitulates the developmental characteristics of articular cartilage can be used to examine the maturation and degeneration of cartilage and produce fully functional neotissue replacements for diseased tissue.This study examined the development of articular cartilage neotissue within a self-assembling process in two phases. In the first phase, articular cartilage constructs were examined at 1, 4, 7, 10, 14, 28, 42, and 56 days immunohistochemically, histologically, and through biochemical analysis for total collagen and glycosaminoglycan (GAG content. Based on statistical changes in GAG and collagen levels, four time points from the first phase (7, 14, 28, and 56 days were chosen to carry into the second phase, where the constructs were studied in terms of their mechanical characteristics, relative amounts of collagen types II and VI, and specific GAG types (chondroitin 4-sulfate, chondroitin 6-sulfate, dermatan sulfate, and hyaluronan. Collagen type VI was present in initial abundance and then localized to a pericellular distribution at 4 wks. N-cadherin activity also spiked at early stages of neotissue development, suggesting that self-assembly is mediated through a minimization of free energy. The percentage of collagen type II to total collagen significantly increased over time, while the proportion of collagen type VI to total collagen decreased between 1 and 2 wks. The chondroitin 6- to 4- sulfate ratio decreased steadily during construct maturation. In addition, the compressive properties reached a plateau and tensile characteristics peaked at 4 wks.The indices of cartilage formation examined in this study suggest that tissue maturation in self-assembled articular cartilage mirrors known developmental processes for native tissue. In terms of tissue engineering, it is

  15. Self-assembling triblock proteins for biofunctional surface modification

    Science.gov (United States)

    Fischer, Stephen E.

    Despite the tremendous promise of cell/tissue engineering, significant challenges remain in engineering functional scaffolds to precisely regulate the complex processes of tissue growth and development. As the point of contact between the cells and the scaffold, the scaffold surface plays a major role in mediating cellular behaviors. In this dissertation, the development and utility of self-assembling, artificial protein hydrogels as biofunctional surface modifiers is described. The design of these recombinant proteins is based on a telechelic triblock motif, in which a disordered polyelectrolyte central domain containing embedded bioactive ligands is flanked by two leucine zipper domains. Under moderate conditions of temperature and pH, the leucine zipper end domains form amphiphilic alpha-helices that reversibly associate into homo-trimeric aggregates, driving hydrogel formation. Moreover, the amphiphilic nature of these helical domains enables surface adsorption to a variety of scaffold materials to form biofunctional protein coatings. The nature and stability of these coatings in various solution conditions, and their interaction with mammalian cells is the primary focus of this dissertation. In particular, triblock protein coatings functionalized with cell recognition sequences are shown to produce well-defined surfaces with precise control over ligand density. The impact of this is demonstrated in multiple cell types through ligand density-dependent cell-substrate interactions. To improve the stability of these physically self-assembled coatings, two covalent crosslinking strategies are described---one in which a zero-length chemical crosslinker (EDC) is utilized and a second in which disulfide bonds are engineered into the recombinant proteins. These targeted crosslinking approaches are shown to increase the stability of surface adsorbed protein layers with minimal effect on the presentation of many bioactive ligands. Finally, to demonstrate the versatility

  16. Expression of lectin-like transcript-1 in human tissues [version 1; referees: 1 approved, 2 approved with reservations

    Directory of Open Access Journals (Sweden)

    Alba Llibre

    2016-12-01

    Full Text Available Background: Receptor-ligand pairs of C-type lectin-like proteins have been shown to play an important role in cross talk between lymphocytes, as well as in immune responses within concrete tissues and structures, such as the skin or the germinal centres. The CD161-Lectin-like Transcript 1 (LLT1 pair has gained particular attention in recent years, yet a detailed analysis of LLT1 distribution in human tissue is lacking. One reason for this is the limited availability and poor characterisation of anti-LLT1 antibodies. Methods: We assessed the staining capabilities of a novel anti-LLT1 antibody clone (2H7, both by immunohistochemistry and flow cytometry, showing its efficiency at LLT1 recognition in both settings. We then analysed LLT1 expression in a wide variety of human tissues. Results: We found LLT1 expression in circulating B cells and monocytes, but not in lung and liver-resident macrophages. We found strikingly high LLT1 expression in immune-privileged sites, such as the brain, placenta and testes, and confirmed the ability of LLT1 to inhibit NK cell function. Conclusions: Overall, this study contributes to the development of efficient tools for the study of LLT1. Moreover, its expression in different healthy human tissues and, particularly, in immune-privileged sites, establishes LLT1 as a good candidate as a regulator of immune responses.

  17. Combining Targeted Agents With Modern Radiotherapy in Soft Tissue Sarcomas

    Science.gov (United States)

    Wong, Philip; Houghton, Peter; Kirsch, David G.; Finkelstein, Steven E.; Monjazeb, Arta M.; Xu-Welliver, Meng; Dicker, Adam P.; Ahmed, Mansoor; Vikram, Bhadrasain; Teicher, Beverly A.; Coleman, C. Norman; Machtay, Mitchell; Curran, Walter J.

    2014-01-01

    Improved understanding of soft-tissue sarcoma (STS) biology has led to better distinction and subtyping of these diseases with the hope of exploiting the molecular characteristics of each subtype to develop appropriately targeted treatment regimens. In the care of patients with extremity STS, adjunctive radiation therapy (RT) is used to facilitate limb and function, preserving surgeries while maintaining five-year local control above 85%. In contrast, for STS originating from nonextremity anatomical sites, the rate of local recurrence is much higher (five-year local control is approximately 50%) and a major cause of death and morbidity in these patients. Incorporating novel technological advancements to administer accurate RT in combination with novel radiosensitizing agents could potentially improve local control and overall survival. RT efficacy in STS can be increased by modulating biological pathways such as angiogenesis, cell cycle regulation, cell survival signaling, and cancer-host immune interactions. Previous experiences, advancements, ongoing research, and current clinical trials combining RT with agents modulating one or more of the above pathways are reviewed. The standard clinical management of patients with STS with pretreatment biopsy, neoadjuvant treatment, and primary surgery provides an opportune disease model for interrogating translational hypotheses. The purpose of this review is to outline a strategic vision for clinical translation of preclinical findings and to identify appropriate targeted agents to combine with radiotherapy in the treatment of STS from different sites and/or different histology subtypes. PMID:25326640

  18. Design of a nanocomposite substrate inducing adult stem cell assembly and progression toward an Epiblast-like or Primitive Endoderm-like phenotype via mechanotransduction.

    Science.gov (United States)

    Morena, Francesco; Armentano, Ilaria; Montanucci, Pia; Argentati, Chiara; Fortunati, Elena; Montesano, Simona; Bicchi, Ilaria; Pescara, Teresa; Pennoni, Ilaria; Mattioli, Samantha; Torre, Luigi; Latterini, Loredana; Emiliani, Carla; Basta, Giuseppe; Calafiore, Riccardo; Kenny, Josè Maria; Martino, Sabata

    2017-11-01

    This work shows that the active interaction between human umbilical cord matrix stem cells and Poly (l-lactide)acid (PLLA) and PLLA/Multi Walled Carbon Nanotubes (MWCNTs) nanocomposite films results in the stem cell assembly as a spheroid conformation and affects the stem cell fate transition. We demonstrated that spheroids directly respond to a tunable surface and the bulk properties (electric, dielectric and thermal) of plain and nanocomposite PLLA films by triggering a mechanotransduction axis. This stepwise process starts from tethering of the cells' focal adhesion proteins to the surface, together with the adherens junctions between cells. Both complexes transmit traction forces to F-Actin stress fibres that link Filamin-A and Myosin-IIA proteins, generating a biological scaffold, with increased stiffening conformation from PLLA to PLLA/MWCNTs, and enable the nucleoskeleton proteins to boost chromatin reprogramming processes. Herein, the opposite expression of NANOG and GATA6 transcription factors, together with other lineage specification related proteins, steer spheroids toward an Epiblast-like or Primitive Endoderm-like lineage commitment, depending on the absence or presence of 1 wt% MWCNTs, respectively. This work represents a pioneering effort to create a stem cell/material interface that can model the stem cell fate transition under growth culture conditions. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Extracellular matrix fragmentation in young, healthy cartilaginous tissues

    Directory of Open Access Journals (Sweden)

    RJ Craddock

    2018-02-01

    Full Text Available Although the composition and structure of cartilaginous tissues is complex, collagen II fibrils and aggrecan are the most abundant assemblies in both articular cartilage (AC and the nucleus pulposus (NP of the intervertebral disc (IVD. Whilst structural heterogeneity of intact aggrecan ( containing three globular domains is well characterised, the extent of aggrecan fragmentation in healthy tissues is poorly defined. Using young, yet skeletally mature (18-30 months, bovine AC and NP tissues, it was shown that, whilst the ultrastructure of intact aggrecan was tissue-dependent, most molecules (AC: 95 %; NP: 99.5 % were fragmented (lacking one or more globular domains. Fragments were significantly smaller and more structurally heterogeneous in the NP compared with the AC (molecular area; AC: 8543 nm2; NP: 4625 nm2; p < 0.0001. In contrast, fibrillar collagen appeared structurally intact and tissue-invariant. Molecular fragmentation is considered indicative of a pathology; however, these young, skeletally mature tissues were histologically and mechanically (reduced modulus: AC: ≈ 500 kPa; NP: ≈ 80 kPa comparable to healthy tissues and devoid of notable gelatinase activity (compared with rat dermis. As aggrecan fragmentation was prevalent in neonatal bovine AC (99.5 % fragmented, molecular area: 5137 nm2 as compared with mature AC (95.0 % fragmented, molecular area: 8667 nm2, it was hypothesised that targeted proteolysis might be an adaptive process that modified aggrecan packing (as simulated computationally and, hence, tissue charge density, mechanical properties and porosity. These observations provided a baseline against which pathological and/or age-related fragmentation of aggrecan could be assessed and suggested that new strategies might be required to engineer constructs that mimic the mechanical properties of native cartilaginous tissues.

  20. Self-assembled nanomaterials for photoacoustic imaging

    Science.gov (United States)

    Wang, Lei; Yang, Pei-Pei; Zhao, Xiao-Xiao; Wang, Hao

    2016-01-01

    In recent years, extensive endeavors have been paid to construct functional self-assembled nanomaterials for various applications such as catalysis, separation, energy and biomedicines. To date, different strategies have been developed for preparing nanomaterials with diversified structures and functionalities via fine tuning of self-assembled building blocks. In terms of biomedical applications, bioimaging technologies are urgently calling for high-efficient probes/contrast agents for high-performance bioimaging. Photoacoustic (PA) imaging is an emerging whole-body imaging modality offering high spatial resolution, deep penetration and high contrast in vivo. The self-assembled nanomaterials show high stability in vivo, specific tolerance to sterilization and prolonged half-life stability and desirable targeting properties, which is a kind of promising PA contrast agents for biomedical imaging. Herein, we focus on summarizing recent advances in smart self-assembled nanomaterials with NIR absorption as PA contrast agents for biomedical imaging. According to the preparation strategy of the contrast agents, the self-assembled nanomaterials are categorized into two groups, i.e., the ex situ and in situ self-assembled nanomaterials. The driving forces, assembly modes and regulation of PA properties of self-assembled nanomaterials and their applications for long-term imaging, enzyme activity detection and aggregation-induced retention (AIR) effect for diagnosis and therapy are emphasized. Finally, we conclude with an outlook towards future developments of self-assembled nanomaterials for PA imaging.

  1. Self-assembled nanomaterials for photoacoustic imaging.

    Science.gov (United States)

    Wang, Lei; Yang, Pei-Pei; Zhao, Xiao-Xiao; Wang, Hao

    2016-02-07

    In recent years, extensive endeavors have been paid to construct functional self-assembled nanomaterials for various applications such as catalysis, separation, energy and biomedicines. To date, different strategies have been developed for preparing nanomaterials with diversified structures and functionalities via fine tuning of self-assembled building blocks. In terms of biomedical applications, bioimaging technologies are urgently calling for high-efficient probes/contrast agents for high-performance bioimaging. Photoacoustic (PA) imaging is an emerging whole-body imaging modality offering high spatial resolution, deep penetration and high contrast in vivo. The self-assembled nanomaterials show high stability in vivo, specific tolerance to sterilization and prolonged half-life stability and desirable targeting properties, which is a kind of promising PA contrast agents for biomedical imaging. Herein, we focus on summarizing recent advances in smart self-assembled nanomaterials with NIR absorption as PA contrast agents for biomedical imaging. According to the preparation strategy of the contrast agents, the self-assembled nanomaterials are categorized into two groups, i.e., the ex situ and in situ self-assembled nanomaterials. The driving forces, assembly modes and regulation of PA properties of self-assembled nanomaterials and their applications for long-term imaging, enzyme activity detection and aggregation-induced retention (AIR) effect for diagnosis and therapy are emphasized. Finally, we conclude with an outlook towards future developments of self-assembled nanomaterials for PA imaging.

  2. Micro- and nanotechnology in cardiovascular tissue engineering

    International Nuclear Information System (INIS)

    Zhang Boyang; Xiao Yun; Hsieh, Anne; Thavandiran, Nimalan; Radisic, Milica

    2011-01-01

    While in nature the formation of complex tissues is gradually shaped by the long journey of development, in tissue engineering constructing complex tissues relies heavily on our ability to directly manipulate and control the micro-cellular environment in vitro. Not surprisingly, advancements in both microfabrication and nanofabrication have powered the field of tissue engineering in many aspects. Focusing on cardiac tissue engineering, this paper highlights the applications of fabrication techniques in various aspects of tissue engineering research: (1) cell responses to micro- and nanopatterned topographical cues, (2) cell responses to patterned biochemical cues, (3) controlled 3D scaffolds, (4) patterned tissue vascularization and (5) electromechanical regulation of tissue assembly and function.

  3. Modeling of heat transfer in a vascular tissue-like medium during an interstitial hyperthermia process.

    Science.gov (United States)

    Hassanpour, Saeid; Saboonchi, Ahmad

    2016-12-01

    This paper aims to evaluate the role of small vessels in heat transfer mechanisms of a tissue-like medium during local intensive heating processes, for example, an interstitial hyperthermia treatment. To this purpose, a cylindrical tissue with two co- and counter-current vascular networks and a central heat source is introduced. Next, the energy equations of tissue, supply fluid (arterial blood), and return fluid (venous blood) are derived using porous media approach. Then, a 2D computer code is developed to predict the temperature of blood (fluid phase) and tissue (solid phase) by conventional volume averaging method and a more realistic solution method. In latter method, despite the volume averaging the blood of interconnect capillaries is separated from the arterial and venous blood phases. It is found that in addition to blood perfusion rate, the arrangement of vascular network has considerable effects on the pattern and amount of the achieved temperature. In contrast to counter-current network, the co-current network of vessels leads to considerable asymmetric pattern of temperature contours and relocation of heat affected zone along the blood flow direction. However this relocation can be prevented by changing the site of hyperthermia heat source. The results show that the cooling effect of co-current blood vessels during of interstitial heating is more efficient. Despite much anatomical dissimilarities, these findings can be useful in designing of protocols for hyperthermia cancer treatment of living tissue. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Portable fluorescence lifetime spectroscopy system for in-situ interrogation of biological tissues

    Science.gov (United States)

    Saito Nogueira, Marcelo; Cosci, Alessandro; Teixeira Rosa, Ramon Gabriel; Salvio, Ana Gabriela; Pratavieira, Sebastião; Kurachi, Cristina

    2017-12-01

    Fluorescence spectroscopy and lifetime techniques are potential methods for optical diagnosis and characterization of biological tissues with an in-situ, fast, and noninvasive interrogation. Several diseases may be diagnosed due to differences in the fluorescence spectra of targeted fluorophores, when, these spectra are similar, considering steady-state fluorescence, others may be detected by monitoring their fluorescence lifetime. Despite this complementarity, most of the current fluorescence lifetime systems are not robust and portable, and not being feasible for clinical applications. We describe the assembly of a fluorescence lifetime spectroscopy system in a suitcase, its characterization, and validation with clinical measurements of skin lesions. The assembled system is all encased and robust, maintaining its mechanical, electrical, and optical stability during transportation, and is feasible for clinical measurements. The instrument response function measured was about 300 ps, and the system is properly calibrated. At the clinical study, the system showed to be reliable, and the achieved spectroscopy results support its potential use as an auxiliary tool for skin diagnostics.

  5. Assembly line performance and modeling

    Science.gov (United States)

    Rane, Arun B.; Sunnapwar, Vivek K.

    2017-09-01

    Automobile sector forms the backbone of manufacturing sector. Vehicle assembly line is important section in automobile plant where repetitive tasks are performed one after another at different workstations. In this thesis, a methodology is proposed to reduce cycle time and time loss due to important factors like equipment failure, shortage of inventory, absenteeism, set-up, material handling, rejection and fatigue to improve output within given cost constraints. Various relationships between these factors, corresponding cost and output are established by scientific approach. This methodology is validated in three different vehicle assembly plants. Proposed methodology may help practitioners to optimize the assembly line using lean techniques.

  6. Method of transporting fuel assemblies

    International Nuclear Information System (INIS)

    Okada, Katsutoshi.

    1979-01-01

    Purpose: To enable safety transportation of fuel assemblies for FBR type reactors by surrounding each of fuel elements in a wrapper tube by a rubbery, hollow cylindrical container and by sealing medium such as air to the inside of the container. Method: A fuel element is contained in a hollow cylindrical rubber-like tube. The fuel element has an upper end plug, a lower end plug and a wire spirally wound around the outer periphery. Upon transportation of the fuel assemblies, each of the fuel elements is covered with the container and arranged in the wrapper tube and then the fuel assemblies are assembled. Then, medium such as air is sealed for each of the fuel elements by way of an opening and then the opening is tightly closed. Before loading the transported fuel assemblies in the reactor, the medium is discharged through the opening and the container is completely extracted and removed from the inside of the wrapper tube. (Seki, T.)

  7. Self-Assembly of Octopus Nanoparticles into Pre-Programmed Finite Clusters

    Science.gov (United States)

    Halverson, Jonathan; Tkachenko, Alexei

    2012-02-01

    The precise control of the spatial arrangement of nanoparticles (NP) is often required to take full advantage of their novel optical and electronic properties. NPs have been shown to self-assemble into crystalline structures using either patchy surface regions or complementary DNA strands to direct the assembly. Due to a lack of specificity of the interactions these methods lead to only a limited number of structures. An emerging approach is to bind ssDNA at specific sites on the particle surface making so-called octopus NPs. Using octopus NPs we investigate the inverse problem of the self-assembly of finite clusters. That is, for a given target cluster (e.g., arranging the NPs on the vertices of a dodecahedron) what are the minimum number of complementary DNA strands needed for the robust self-assembly of the cluster from an initially homogeneous NP solution? Based on the results of Brownian dynamics simulations we have compiled a set of design rules for various target clusters including cubes, pyramids, dodecahedrons and truncated icosahedrons. Our approach leads to control over the kinetic pathway and has demonstrated nearly perfect yield of the target.

  8. The assembly of GM1 glycolipid- and cholesterol-enriched raft-like membrane microdomains is important for giardial encystation.

    Science.gov (United States)

    De Chatterjee, Atasi; Mendez, Tavis L; Roychowdhury, Sukla; Das, Siddhartha

    2015-05-01

    Although encystation (or cyst formation) is an important step of the life cycle of Giardia, the cellular events that trigger encystation are poorly understood. Because membrane microdomains are involved in inducing growth and differentiation in many eukaryotes, we wondered if these raft-like domains are assembled by this parasite and participate in the encystation process. Since the GM1 ganglioside is a major constituent of mammalian lipid rafts (LRs) and known to react with cholera toxin B (CTXB), we used Alexa Fluor-conjugated CTXB and GM1 antibodies to detect giardial LRs. Raft-like structures in trophozoites are located in the plasma membranes and on the periphery of ventral discs. In cysts, however, they are localized in the membranes beneath the cyst wall. Nystatin and filipin III, two cholesterol-binding agents, and oseltamivir (Tamiflu), a viral neuraminidase inhibitor, disassembled the microdomains, as evidenced by reduced staining of trophozoites with CTXB and GM1 antibodies. GM1- and cholesterol-enriched LRs were isolated from Giardia by density gradient centrifugation and found to be sensitive to nystatin and oseltamivir. The involvement of LRs in encystation could be supported by the observation that raft inhibitors interrupted the biogenesis of encystation-specific vesicles and cyst production. Furthermore, culturing of trophozoites in dialyzed medium containing fetal bovine serum (which is low in cholesterol) reduced raft assembly and encystation, which could be rescued by adding cholesterol from the outside. Our results suggest that Giardia is able to form GM1- and cholesterol-enriched lipid rafts and these raft domains are important for encystation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  9. MiR-338-5p Promotes Inflammatory Response of Fibroblast-Like Synoviocytes in Rheumatoid Arthritis via Targeting SPRY1.

    Science.gov (United States)

    Yang, Yan; Wang, Yanfeng; Liang, Qingwei; Yao, Lutian; Gu, Shizhong; Bai, Xizhuang

    2017-08-01

    Our purpose is to study the roles of microRNA-338-5p (miR-338-5p) on the proliferation, invasion, and inflammatory response of fibroblast-like synoviocytes (SFs) in rheumatoid arthritis patients by regulating SPRY1. The target relationship between miR-338-5p and SPRY1 was validated through luciferase reporter system. The expression of miR-338-5p and SPRY1 in synovial tissues and synovial cells were detected using RT-PCR and western blot. The mimics and inhibitors of miR-338-5p were transfected into SFs. MTT, Transwell, and ELISA assays were used to analyze cell proliferation, invasiveness, and the secreted extracellular pro-inflammatory cytokines (such as IL-1a, IL-6, COX2) levels of SFs. MiR-338-5p was highly expressed in rheumatoid arthritis tissues and cells, and directly down-regulated the expression of SPRY1 in the SFs of rheumatoid arthritis patients. Cell proliferation, invasiveness and the expression level of pro-inflammatory cytokines in synovial cells increased after the transfection of miR-338-5p mimics, while the proliferation, invasion and expression level of pro-inflammatory cytokines decreased after the transfection of miR-338-5p inhibitors. In conclusion,miR-338-5p promoted the proliferation, invasion and inflammatory reaction in SFs of rheumatoid arthritis by directly down-regulating SPRY1 expression. J. Cell. Biochem. 118: 2295-2301, 2017. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  10. CAD Parts-Based Assembly Modeling by Probabilistic Reasoning

    KAUST Repository

    Zhang, Kai-Ke

    2016-04-11

    Nowadays, increasing amount of parts and sub-assemblies are publicly available, which can be used directly for product development instead of creating from scratch. In this paper, we propose an interactive design framework for efficient and smart assembly modeling, in order to improve the design efficiency. Our approach is based on a probabilistic reasoning. Given a collection of industrial assemblies, we learn a probabilistic graphical model from the relationships between the parts of assemblies. Then in the modeling stage, this probabilistic model is used to suggest the most likely used parts compatible with the current assembly. Finally, the parts are assembled under certain geometric constraints. We demonstrate the effectiveness of our framework through a variety of assembly models produced by our prototype system. © 2015 IEEE.

  11. CAD Parts-Based Assembly Modeling by Probabilistic Reasoning

    KAUST Repository

    Zhang, Kai-Ke; Hu, Kai-Mo; Yin, Li-Cheng; Yan, Dongming; Wang, Bin

    2016-01-01

    Nowadays, increasing amount of parts and sub-assemblies are publicly available, which can be used directly for product development instead of creating from scratch. In this paper, we propose an interactive design framework for efficient and smart assembly modeling, in order to improve the design efficiency. Our approach is based on a probabilistic reasoning. Given a collection of industrial assemblies, we learn a probabilistic graphical model from the relationships between the parts of assemblies. Then in the modeling stage, this probabilistic model is used to suggest the most likely used parts compatible with the current assembly. Finally, the parts are assembled under certain geometric constraints. We demonstrate the effectiveness of our framework through a variety of assembly models produced by our prototype system. © 2015 IEEE.

  12. LBNF 1.2 MW TARGET: CONCEPTUAL DESIGN & FABRICATION

    Energy Technology Data Exchange (ETDEWEB)

    Crowley, Cory F. [Fermilab; Ammigan, K. [Fermilab; Anderson, K. [Fermilab; Hartsell, B. [Fermilab; Hurh, P. [Fermilab; Hylen, J. [Fermilab; Zwaska, R. [Fermilab

    2015-06-29

    Fermilab’s Long-Baseline Neutrino Facility (LBNF) will utilize a modified design based on the NuMI low energy target that is reconfigured to accommodate beam operation at 1.2 MW. Achieving this power with a graphite target material and ancillary systems originally rated for 400 kW requires several design changes and R&D efforts related to material bonding and electrical isolation. Target cooling, structural design, and fabrication techniques must address higher stresses and heat loads that will be present during 1.2 MW operation, as the assembly will be subject to cyclic loads and thermal expansion. Mitigations must be balanced against compromises in neutrino yield. Beam monitoring and subsystem instrumentation will be updated and added to ensure confidence in target positioning and monitoring. Remote connection to the target hall support structure must provide for the eventual upgrade to a 2.4 MW target design, without producing excessive radioactive waste or unreasonable exposure to technicians during reconfiguration. Current designs and assembly layouts will be presented, in addition to current findings on processes and possibilities for prototype and final assembly fabrication.

  13. LBNF 1.2 MW Target: Conceptual Design & Fabrication

    Energy Technology Data Exchange (ETDEWEB)

    Crowley, C. [Fermilab; Ammigan, K. [Fermilab; Anderson, K. [Fermilab; Hartsell, B. [Fermilab; Hurh, P. [Fermilab; Hylen, J. [Fermilab; Zwaska, R. [Fermilab

    2015-06-01

    Fermilab’s Long-Baseline Neutrino Facility (LBNF) will utilize a modified design based on the NuMI low energy target that is reconfigured to accommodate beam operation at 1.2 MW. Achieving this power with a graphite target material and ancillary systems originally rated for 400 kW requires several design changes and R&D efforts related to material bonding and electrical isolation. Target cooling, structural design, and fabrication techniques must address higher stresses and heat loads that will be present during 1.2 MW operation, as the assembly will be subject to cyclic loads and thermal expansion. Mitigations must be balanced against compromises in neutrino yield. Beam monitoring and subsystem instrumentation will be updated and added to ensure confidence in target positioning and monitoring. Remote connection to the target hall support structure must provide for the eventual upgrade to a 2.4 MW target design, without producing excessive radioactive waste or unreasonable exposure to technicians during reconfiguration. Current designs and assembly layouts will be presented, in addition to current findings on processes and possibilities for prototype and final assembly fabrication.

  14. Self-Assembled Nanocarriers Based on Amphiphilic Natural Polymers for Anti- Cancer Drug Delivery Applications.

    Science.gov (United States)

    Sabra, Sally; Abdelmoneem, Mona; Abdelwakil, Mahmoud; Mabrouk, Moustafa Taha; Anwar, Doaa; Mohamed, Rania; Khattab, Sherine; Bekhit, Adnan; Elkhodairy, Kadria; Freag, May; Elzoghby, Ahmed

    2017-01-01

    Micellization provides numerous merits for the delivery of water insoluble anti-cancer therapeutic agents including a nanosized 'core-shell' drug delivery system. Recently, hydrophobically-modified polysaccharides and proteins are attracting much attention as micelle forming polymers to entrap poorly soluble anti-cancer drugs. By virtue of their small size, the self-assembled micelles can passively target tumor tissues via enhanced permeation and retention effect (EPR). Moreover, the amphiphilic micelles can be exploited for active-targeted drug delivery by attaching specific targeting ligands to the outer micellar hydrophilic surface. Here, we review the conjugation techniques, drug loading methods, physicochemical characteristics of the most important amphiphilic polysaccharides and proteins used as anti-cancer drug delivery systems. Attention focuses on the mechanisms of tumor-targeting and enhanced anti-tumor efficacy of the encapsulated drugs. This review will highlight the remarkable advances of hydrophobized polysaccharide and protein micelles and their potential applications as anti-cancer drug delivery nanosystems. Micellar nanocarriers fabricated from amphiphilic natural polymers hold great promise as vehicles for anti-cancer drugs. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  15. Comprehensive irradiation of head and neck cancer using conformal multisegmental fields: assessment of target coverage and noninvolved tissue sparing

    International Nuclear Information System (INIS)

    Eisbruch, Avraham; Marsh, Lon H.; Martel, Mary K.; Ship, Jonathan A.; Haken, Randall ten; Pu, Anthony T.; Fraass, Benedick A.; Lichter, Allen S.

    1998-01-01

    Purpose: Conformal treatment using static multisegmental intensity modulation was developed for patients requiring comprehensive irradiation for head and neck cancer. The major aim is sparing major salivary gland function while adequately treating the targets. To assess the adequacy of the conformal plans regarding target coverage and dose homogeneity, they were compared with standard irradiation plans. Methods and Materials: Fifteen patients with stage III/IV head and neck cancer requiring comprehensive, bilateral neck irradiation participated in this study. CT-based treatment plans included five to six nonopposed fields, each having two to four in-field segments. Fields and segments were devised using beam's eye views of the planning target volumes (PTVs), noninvolved organs, and isodose surfaces, to achieve homogeneous dose distribution that encompassed the targets and spared major salivary gland tissue. For comparison, standard three-field radiation plans were devised retrospectively for each patient, with the same CT-derived targets used for the clinical (conformal) plans. Saliva flow rates from each major salivary gland were measured before and periodically after treatment. Results: On average, the minimal dose to the primary PTVs in the conformal plans [95.2% of the prescribed dose, standard deviation (SD) 4%] was higher than in the standard plans (91%, SD 7%; p = 0.02), and target volumes receiving <95% or <90% of the prescribed dose were smaller in the conformal plans (p = 0.004 and 0.02, respectively). Similar advantages of the conformal plans compared to standard plans were found in ipsilateral jugular nodes PTV coverage. The reason for underdosing in the standard treatment plans was primarily failure of electron beams to fully encompass targets. No significant differences were found in contralateral jugular or posterior neck nodes coverage. The minimal dose to the retropharyngeal nodes was higher in the standard plans. However, all conformal plans

  16. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    “Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  17. Establishment and characterization of novel epithelial-like cell lines derived from human periodontal ligament tissue in vitro.

    Science.gov (United States)

    Tansriratanawong, Kallapat; Ishikawa, Hiroshi; Toyomura, Junko; Sato, Soh

    2017-10-01

    In this study, novel human-derived epithelial-like cells (hEPLCs) lines were established from periodontal ligament (PDL) tissues, which were composed of a variety of cell types and exhibited complex cellular activities. To elucidate the putative features distinguishing these from epithelial rest of Malassez (ERM), we characterized hEPLCs based on cell lineage markers and tight junction protein expression. The aim of this study was, therefore, to establish and characterize hEPLCs lines from PDL tissues. The hEPLCs were isolated from PDL of third molar teeth. Cellular morphology and cell organelles were observed thoroughly. The characteristics of epithelial-endothelial-mesenchymal-like cells were compared in several markers by gene expression and immunofluorescence, to ERM and human umbilical-vein endothelial cells (HUVECs). The resistance between cellular junctions was assessed by transepithelial electron resistance, and inflammatory cytokines were detected by ELISA after infecting hEPLCs with periodontopathic bacteria. The hEPLCs developed into small epithelial-like cells in pavement appearance similar to ERM. However, gene expression patterns and immunofluorescence results were different from ERM and HUVECs, especially in tight junction markers (Claudin, ZO-1, and Occludins), and endothelial markers (vWF, CD34). The transepithelial electron resistance indicated higher resistance in hEPLCs, as compared to ERM. Periodontopathic bacteria were phagocytosed with upregulation of inflammatory cytokine secretion within 24 h. In conclusion, hEPLCs that were derived using the single cell isolation method formed tight multilayers colonies, as well as strongly expressed tight junction markers in gene expression and immunofluorescence. Novel hEPLCs lines exhibited differently from ERM, which might provide some specific functions such as metabolic exchange and defense mechanism against bacterial invasion in periodontal tissue.

  18. Targeting Extracellular DNA to Deliver IGF-1 to the Injured Heart

    Science.gov (United States)

    Khan, Raffay S.; Martinez, Mario D.; Sy, Jay C.; Pendergrass, Karl D.; Che, Pao-Lin; Brown, Milton E.; Cabigas, E. Bernadette; Dasari, Madhuri; Murthy, Niren; Davis, Michael E.

    2014-03-01

    There is a great need for the development of therapeutic strategies that can target biomolecules to damaged myocardium. Necrosis of myocardium during a myocardial infarction (MI) is characterized by extracellular release of DNA, which can serve as a potential target for ischemic tissue. Hoechst, a histological stain that binds to double-stranded DNA can be conjugated to a variety of molecules. Insulin-like growth factor-1 (IGF-1), a small protein/polypeptide with a short circulating-half life is cardioprotective following MI but its clinical use is limited by poor delivery, as intra-myocardial injections have poor retention and chronic systemic presence has adverse side effects. Here, we present a novel delivery vehicle for IGF-1, via its conjugation to Hoechst for targeting infarcted tissue. Using a mouse model of ischemia-reperfusion, we demonstrate that intravenous delivery of Hoechst-IGF-1 results in activation of Akt, a downstream target of IGF-1 and protects from cardiac fibrosis and dysfunction following MI.

  19. Quantifying quality in DNA self-assembly

    Science.gov (United States)

    Wagenbauer, Klaus F.; Wachauf, Christian H.; Dietz, Hendrik

    2014-01-01

    Molecular self-assembly with DNA is an attractive route for building nanoscale devices. The development of sophisticated and precise objects with this technique requires detailed experimental feedback on the structure and composition of assembled objects. Here we report a sensitive assay for the quality of assembly. The method relies on measuring the content of unpaired DNA bases in self-assembled DNA objects using a fluorescent de-Bruijn probe for three-base ‘codons’, which enables a comparison with the designed content of unpaired DNA. We use the assay to measure the quality of assembly of several multilayer DNA origami objects and illustrate the use of the assay for the rational refinement of assembly protocols. Our data suggests that large and complex objects like multilayer DNA origami can be made with high strand integration quality up to 99%. Beyond DNA nanotechnology, we speculate that the ability to discriminate unpaired from paired nucleic acids in the same macromolecule may also be useful for analysing cellular nucleic acids. PMID:24751596

  20. Tissue- and stage-specific Wnt target gene expression is controlled subsequent to beta-catenin recruitment to cis-regulatory modules

    NARCIS (Netherlands)

    Nakamura, Y.; de Paiva Alves, E.; Veenstra, G.J.C.; Hoppler, S.

    2016-01-01

    Key signalling pathways, such as canonical Wnt/beta-catenin signalling, operate repeatedly to regulate tissue- and stage-specific transcriptional responses during development. Although recruitment of nuclear beta-catenin to target genomic loci serves as the hallmark of canonical Wnt signalling,

  1. Sol gel-derived hydroxyapatite films over porous calcium polyphosphate substrates for improved tissue engineering of osteochondral-like constructs.

    Science.gov (United States)

    Lee, Whitaik David; Gawri, Rahul; Pilliar, Robert M; Stanford, William L; Kandel, Rita A

    2017-10-15

    Integration of in vitro-formed cartilage on a suitable substrate to form tissue-engineered implants for osteochondral defect repair is a considerable challenge. In healthy cartilage, a zone of calcified cartilage (ZCC) acts as an intermediary for mechanical force transfer from soft to hard tissue, as well as an effective interlocking structure to better resist interfacial shear forces. We have developed biphasic constructs that consist of scaffold-free cartilage tissue grown in vitro on, and interdigitated with, porous calcium polyphosphate (CPP) substrates. However, as CPP degrades, it releases inorganic polyphosphates (polyP) that can inhibit local mineralization, thereby preventing the formation of a ZCC at the interface. Thus, we hypothesize that coating CPP substrate with a layer of hydroxyapatite (HA) might prevent or limit this polyP release. To investigate this we tested both inorganic or organic sol-gel processing methods, asa barrier coating on CPP substrate to inhibit polyP release. Both types of coating supported the formation of ZCC in direct contact with the substrate, however the ZCC appeared more continuous in the tissue formed on the organic HA sol gel coated CPP. Tissues formed on coated substrates accumulated comparable quantities of extracellular matrix and mineral, but tissues formed on organic sol-gel (OSG)-coated substrates accumulated less polyP than tissues formed on inorganic sol-gel (ISG)-coated substrates. Constructs formed with OSG-coated CPP substrates had greater interfacial shear strength than those formed with ISG-coated and non-coated substrates. These results suggest that the OSG coating method can modify the location and distribution of ZCC and can be used to improve the mechanical integrity of tissue-engineered constructs formed on porous CPP substrates. Articular cartilage interfaces with bone through a zone of calcified cartilage. This study describes a method to generate an "osteochondral-like" implant that mimics this

  2. Yeast Microcapsule-Mediated Targeted Delivery of Diverse Nanoparticles for Imaging and Therapy via the Oral Route.

    Science.gov (United States)

    Zhou, Xing; Zhang, Xiangjun; Han, Songling; Dou, Yin; Liu, Mengyu; Zhang, Lin; Guo, Jiawei; Shi, Qing; Gong, Genghao; Wang, Ruibing; Hu, Jiang; Li, Xiaohui; Zhang, Jianxiang

    2017-02-08

    Targeting of nanoparticles to distant diseased sites after oral delivery remains highly challenging due to the existence of many biological barriers in the gastrointestinal tract. Here we report targeted oral delivery of diverse nanoparticles in multiple disease models, via a "Trojan horse" strategy based on a bioinspired yeast capsule (YC). Diverse charged nanoprobes including quantum dots (QDs), iron oxide nanoparticles (IONPs), and assembled organic fluorescent nanoparticles can be effectively loaded into YC through electrostatic force-driven spontaneous deposition, resulting in different diagnostic YC assemblies. Also, different positive nanotherapies containing an anti-inflammatory drug indomethacin (IND) or an antitumor drug paclitaxel (PTX) are efficiently packaged into YC. YCs containing either nanoprobes or nanotherapies may be rapidly endocytosed by macrophages and maintained in cells for a relatively long period of time. Post oral administration, nanoparticles packaged in YC are first transcytosed by M cells and sequentially endocytosed by macrophages, then transported to neighboring lymphoid tissues, and finally delivered to remote diseased sites of inflammation or tumor in mice or rats, all through the natural route of macrophage activation, recruitment, and deployment. For the examined acute inflammation model, the targeting efficiency of YC-delivered QDs or IONPs is even higher than that of control nanoprobes administered at the same dose via intravenous injection. Assembled IND or PTX nanotherapies orally delivered via YCs exhibit remarkably potentiated efficacies as compared to nanotherapies alone in animal models of inflammation and tumor, which is consistent with the targeting effect and enhanced accumulation of drug molecules at diseased sites. Consequently, through the intricate transportation route, nanoprobes or nanotherapies enveloped in YC can be preferentially delivered to desired targets, affording remarkably improved efficacies for the

  3. Design study of ITER-like divertor target for DEMO

    International Nuclear Information System (INIS)

    Crescenzi, Fabio; Bachmann, C.; Richou, M.; Roccella, S.; Visca, E.; You, J.-H.

    2015-01-01

    Highlights: • ‘DEMO’ is a near-term Power Plant Conceptual Study (PPCS). • The ITER-like design concept represents a promising solution also for DEMO plasma facing units. • The optimization of PFUs aims to enhance the thermo-mechanical behaviour of the component. • The optimized geometry was evaluated by ITER SDC-IC criteria and in terms of low cycle fatigue (LCF). - Abstract: A near-term water-cooled target solution has to be evaluated together with the required technologies and its power exhaust limit under ‘DEMO’ conditions. The ITER-like design concept based on the mono-block technology using W as armour material and the CuCrZr-IG as structural material with an interlayer of pure copper represents a promising solution also for DEMO. This work reports the design study of an “optimized” ITER-like Water Cooled Divertor able to withstand a heat flux of 10 MW m"−"2, as requested for DEMO operating conditions. The optimization of plasma facing unit (PFU) aims to enhance the thermo-mechanical behaviour of the component by varying some geometrical parameters (monoblock size, interlayer thickness and, tube diameter and thickness). The optimization was performed by means of the multi-variable optimization algorithms using the FEM code ANSYS. The coolant hydraulic conditions (inlet pressure, temperature and velocity) were fixed for simplicity. This study is based on elastic analysis and 3 dimensional modelling. The resulting optimized geometry was evaluated on the basis of the ITER SDC-IC criteria and in terms of low cycle fatigue (LCF). The margin to the critical heat flux (CHF) was also estimated. Further design study (taking into account the effect of neutron radiation on the material properties) together with mock-up fabrication and high-heat-flux (HHF) tests are foreseen in next work programmes.

  4. Design study of ITER-like divertor target for DEMO

    Energy Technology Data Exchange (ETDEWEB)

    Crescenzi, Fabio, E-mail: fabio.crescenzi@enea.it [ENEA, Unità Tecnica Fusione, ENEA C. R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); Bachmann, C. [EFDA, Power Plant Physics and Technology, Boltzmannstraße 2, 85748 Garching (Germany); Richou, M. [CEA, IRFM, F-13108 Saint Paul Lez Durance (France); Roccella, S.; Visca, E. [ENEA, Unità Tecnica Fusione, ENEA C. R. Frascati, via E. Fermi 45, 00044 Frascati (Roma) (Italy); You, J.-H. [Max-Planck-Institut für Plasmaphysik, Boltzmannstr. 2, 85748 Garching (Germany)

    2015-10-15

    Highlights: • ‘DEMO’ is a near-term Power Plant Conceptual Study (PPCS). • The ITER-like design concept represents a promising solution also for DEMO plasma facing units. • The optimization of PFUs aims to enhance the thermo-mechanical behaviour of the component. • The optimized geometry was evaluated by ITER SDC-IC criteria and in terms of low cycle fatigue (LCF). - Abstract: A near-term water-cooled target solution has to be evaluated together with the required technologies and its power exhaust limit under ‘DEMO’ conditions. The ITER-like design concept based on the mono-block technology using W as armour material and the CuCrZr-IG as structural material with an interlayer of pure copper represents a promising solution also for DEMO. This work reports the design study of an “optimized” ITER-like Water Cooled Divertor able to withstand a heat flux of 10 MW m{sup −2}, as requested for DEMO operating conditions. The optimization of plasma facing unit (PFU) aims to enhance the thermo-mechanical behaviour of the component by varying some geometrical parameters (monoblock size, interlayer thickness and, tube diameter and thickness). The optimization was performed by means of the multi-variable optimization algorithms using the FEM code ANSYS. The coolant hydraulic conditions (inlet pressure, temperature and velocity) were fixed for simplicity. This study is based on elastic analysis and 3 dimensional modelling. The resulting optimized geometry was evaluated on the basis of the ITER SDC-IC criteria and in terms of low cycle fatigue (LCF). The margin to the critical heat flux (CHF) was also estimated. Further design study (taking into account the effect of neutron radiation on the material properties) together with mock-up fabrication and high-heat-flux (HHF) tests are foreseen in next work programmes.

  5. Self-assembly model, hepatocytes attachment and inflammatory response for silk fibroin/chitosan scaffolds

    International Nuclear Information System (INIS)

    She Zhending; Feng Qingling; Liu Weiqiang

    2009-01-01

    Silk fibroin is an attractive natural fibrous protein for biomedical application due to its good biocompatibility and high tensile strength. Silk fibroin is apt to form a sheet-like structure during the freeze-drying process, which is not suitable for the scaffold of tissue engineering. In our former study, the adding of chitosan promoted the self-assembly of silk fibroin/chitosan (SFCS) into a three-dimensional (3D) homogeneous porous structure. In this study, a model of the self-assembly is proposed; furthermore, hepatocytes attachment and inflammatory response for the SFCS scaffold were examined. The rigid chain of chitosan may be used as a template for β-sheet formation of silk fibroin, and this may break the sheet structure of the silk fibroin scaffold and promote the formation of a 3D porous structure of the SFCS scaffold. Compared with the polylactic glycolic acid scaffold, the SFCS scaffold further facilitates the attachment of hepatocytes. To investigate the inflammatory response, SFCS scaffolds were implanted into the greater omentum of rats. From the results of implantation, we could demonstrate in vivo that the implantation of SFCS scaffolds resulted in only slight inflammation. Keeping the good histocompatibility and combining the advantages of both fibroin and chitosan, the SFCS scaffold could be a prominent candidate for soft tissue engineering, for example, in the liver.

  6. Self-assembly model, hepatocytes attachment and inflammatory response for silk fibroin/chitosan scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    She Zhending; Feng Qingling [State Key Laboratory of New Ceramics and Fine Processing, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Liu Weiqiang, E-mail: biomater@mail.tsinghua.edu.c [Center for Advanced Materials and Biotechnology, Research Institute of Tsinghua University in Shenzhen, Shenzhen 518057 (China)

    2009-08-15

    Silk fibroin is an attractive natural fibrous protein for biomedical application due to its good biocompatibility and high tensile strength. Silk fibroin is apt to form a sheet-like structure during the freeze-drying process, which is not suitable for the scaffold of tissue engineering. In our former study, the adding of chitosan promoted the self-assembly of silk fibroin/chitosan (SFCS) into a three-dimensional (3D) homogeneous porous structure. In this study, a model of the self-assembly is proposed; furthermore, hepatocytes attachment and inflammatory response for the SFCS scaffold were examined. The rigid chain of chitosan may be used as a template for beta-sheet formation of silk fibroin, and this may break the sheet structure of the silk fibroin scaffold and promote the formation of a 3D porous structure of the SFCS scaffold. Compared with the polylactic glycolic acid scaffold, the SFCS scaffold further facilitates the attachment of hepatocytes. To investigate the inflammatory response, SFCS scaffolds were implanted into the greater omentum of rats. From the results of implantation, we could demonstrate in vivo that the implantation of SFCS scaffolds resulted in only slight inflammation. Keeping the good histocompatibility and combining the advantages of both fibroin and chitosan, the SFCS scaffold could be a prominent candidate for soft tissue engineering, for example, in the liver.

  7. Structural Aspects of Bacterial Outer Membrane Protein Assembly.

    Science.gov (United States)

    Calmettes, Charles; Judd, Andrew; Moraes, Trevor F

    2015-01-01

    The outer membrane of Gram-negative bacteria is predominantly populated by β-Barrel proteins and lipid anchored proteins that serve a variety of biological functions. The proper folding and assembly of these proteins is essential for bacterial viability and often plays a critical role in virulence and pathogenesis. The β-barrel assembly machinery (Bam) complex is responsible for the proper assembly of β-barrels into the outer membrane of Gram-negative bacteria, whereas the localization of lipoproteins (Lol) system is required for proper targeting of lipoproteins to the outer membrane.

  8. Three-dimensional spheroid culture targeting versatile tissue bioassays using a PDMS-based hanging drop array.

    Science.gov (United States)

    Kuo, Ching-Te; Wang, Jong-Yueh; Lin, Yu-Fen; Wo, Andrew M; Chen, Benjamin P C; Lee, Hsinyu

    2017-06-29

    Biomaterial-based tissue culture platforms have emerged as useful tools to mimic in vivo physiological microenvironments in experimental cell biology and clinical studies. We describe herein a three-dimensional (3D) tissue culture platform using a polydimethylsiloxane (PDMS)-based hanging drop array (PDMS-HDA) methodology. Multicellular spheroids can be achieved within 24 h and further boosted by incorporating collagen fibrils in PDMS-HDA. In addition, the spheroids generated from different human tumor cells exhibited distinct sensitivities toward drug chemotherapeutic agents and radiation as compared with two-dimensional (2D) cultures that often lack in vivo-like biological insights. We also demonstrated that multicellular spheroids may enable key hallmarks of tissue-based bioassays, including drug screening, tumor dissemination, cell co-culture, and tumor invasion. Taken together, these results offer new opportunities not only to achieve the active control of 3D multicellular spheroids on demand, but also to establish a rapid and cost-effective platform to study anti-cancer therapeutics and tumor microenvironments.

  9. Self-Assembled Polymeric Micelles Based on Hyaluronic Acid-g-Poly(d,l-lactide-co-glycolide) Copolymer for Tumor Targeting

    Science.gov (United States)

    Son, Gyung Mo; Kim, Hyun Yul; Ryu, Je Ho; Chu, Chong Woo; Kang, Dae Hwan; Park, Su Bum; Jeong, Young-IL

    2014-01-01

    Graft copolymer composed hyaluronic acid (HA) and poly(d,l-lactide-co-glycolide) (PLGA) (HAgLG) was synthesized for antitumor targeting via CD44 receptor of tumor cells. The carboxylic end of PLGA was conjugated with hexamethylenediamine (HMDA) to have amine end group in the end of chain (PLGA-amine). PLGA-amine was coupled with carboxylic acid of HA. Self-assembled polymeric micelles of HAgLG have spherical morphologies and their sizes were around 50–200 nm. Doxorubicin (DOX)-incorporated polymeric micelles were prepared by dialysis procedure. DOX was released over 4 days and its release rate was accelerated by the tumoric enzyme hyaluronidase. To assess targetability of polymeric micelles, CD44-positive HepG2 cells were employed treated with fluorescein isothiocyanate (FITC)-labeled polymeric micelles. HepG2 cells strongly expressed green fluorescence at the cell membrane and cytosol. However, internalization of polymeric micelles were significantly decreased when free HA was pretreated to block the CD44 receptor. Furthermore, the CD44-specific anticancer activity of HAgLG polymeric micelles was confirmed using CD44-negative CT26 cells and CD44-positive HepG2 cells. These results indicated that polymeric micelles of HaLG polymeric micelles have targetability against CD44 receptor of tumor cells. We suggest HAgLG polymeric micelles as a promising candidate for specific drug targeting. PMID:25216338

  10. Self-Assembled Polymeric Micelles Based on Hyaluronic Acid-g-Poly(d,l-lactide-co-glycolide Copolymer for Tumor Targeting

    Directory of Open Access Journals (Sweden)

    Gyung Mo Son

    2014-09-01

    Full Text Available Graft copolymer composed hyaluronic acid (HA and poly(d,l-lactide-co-glycolide (PLGA (HAgLG was synthesized for antitumor targeting via CD44 receptor of tumor cells. The carboxylic end of PLGA was conjugated with hexamethylenediamine (HMDA to have amine end group in the end of chain (PLGA-amine. PLGA-amine was coupled with carboxylic acid of HA. Self-assembled polymeric micelles of HAgLG have spherical morphologies and their sizes were around 50–200 nm. Doxorubicin (DOX-incorporated polymeric micelles were prepared by dialysis procedure. DOX was released over 4 days and its release rate was accelerated by the tumoric enzyme hyaluronidase. To assess targetability of polymeric micelles, CD44-positive HepG2 cells were employed treated with fluorescein isothiocyanate (FITC-labeled polymeric micelles. HepG2 cells strongly expressed green fluorescence at the cell membrane and cytosol. However, internalization of polymeric micelles were significantly decreased when free HA was pretreated to block the CD44 receptor. Furthermore, the CD44-specific anticancer activity of HAgLG polymeric micelles was confirmed using CD44-negative CT26 cells and CD44-positive HepG2 cells. These results indicated that polymeric micelles of HaLG polymeric micelles have targetability against CD44 receptor of tumor cells. We suggest HAgLG polymeric micelles as a promising candidate for specific drug targeting.

  11. Identifying wrong assemblies in de novo short read primary ...

    Indian Academy of Sciences (India)

    2016-08-05

    Aug 5, 2016 ... Most of these assemblies are done using some de novo short read assemblers and other related approaches. .... benchmarking projects like Assemblathon 1, Assemblathon ... from a large insert library (at least 1000 bases).

  12. Cadherin adhesion, tissue tension, and noncanonical Wnt signaling regulate fibronectin matrix organization.

    Science.gov (United States)

    Dzamba, Bette J; Jakab, Karoly R; Marsden, Mungo; Schwartz, Martin A; DeSimone, Douglas W

    2009-03-01

    In this study we demonstrate that planar cell polarity signaling regulates morphogenesis in Xenopus embryos in part through the assembly of the fibronectin (FN) matrix. We outline a regulatory pathway that includes cadherin adhesion and signaling through Rac and Pak, culminating in actin reorganization, myosin contractility, and tissue tension, which, in turn, directs the correct spatiotemporal localization of FN into a fibrillar matrix. Increased mechanical tension promotes FN fibril assembly in the blastocoel roof (BCR), while reduced BCR tension inhibits matrix assembly. These data support a model for matrix assembly in tissues where cell-cell adhesions play an analogous role to the focal adhesions of cultured cells by transferring to integrins the tension required to direct FN fibril formation at cell surfaces.

  13. Epithelial-mesenchymal transition: An emerging target in tissue fibrosis

    Science.gov (United States)

    Li, Meirong; Luan, Fuxin; Zhao, Yali; Hao, Haojie; Zhou, Yong; Han, Weidong

    2016-01-01

    Epithelial-mesenchymal transition (EMT) is involved in a variety of tissue fibroses. Fibroblasts/myofibroblasts derived from epithelial cells contribute to the excessive accumulation of fibrous connective tissue in damaged tissue, which can lead to permanent scarring or organ malfunction. Therefore, EMT-related fibrosis cannot be neglected. This review highlights the findings that demonstrate the EMT to be a direct contributor to the fibroblast/myofibroblast population in the development of tissue fibrosis and helps to elucidate EMT-related anti-fibrotic strategies, which may enable the development of therapeutic interventions to suppress EMT and potentially reverse organ fibrosis. PMID:26361988

  14. A novel method to fabricate superhydrophobic surfaces based on well-defined mulberry-like particles and self-assembly of polydimethylsiloxane

    Science.gov (United States)

    Yang, Jinxin; Pi, Pihui; Wen, Xiufang; Zheng, Dafeng; Xu, Mengyi; Cheng, Jiang; Yang, Zhuoru

    2009-01-01

    A superhydrophobic surface was obtained by combining application of CaCO 3/SiO 2 mulberry-like composite particles, which originated from violent stirring and surface modification, and self-assembly of polydimethylsiloxane. Water contact angle and sliding angle of the superhydrophobic surface were measured to be about 164 ± 2.5° and 5°, respectively. The excellent hydrophobicity is attributed to the synergistic effect of micro-submicro-nano-meter scale roughness (fabricated by composite particles) and the low surface energy (provided by polydimethylsiloxane). This procedure makes it possible for widespread applications of superhydrophobic film due to its simplicity and practicability.

  15. Immunodetection of 11 beta-hydroxysteroid dehydrogenase type 2 in human mineralocorticoid target tissues: evidence for nuclear localization.

    Science.gov (United States)

    Shimojo, M; Ricketts, M L; Petrelli, M D; Moradi, P; Johnson, G D; Bradwell, A R; Hewison, M; Howie, A J; Stewart, P M

    1997-03-01

    11 beta-Hydroxysteroid dehydrogenase (11 beta HSI) is an enzyme complex responsible for the conversion of hormonally active cortisol to inactive cortisone; two isoforms of the enzyme have been cloned and characterized. Clinical observations from patients with the hypertensive syndrome apparent mineralocorticoid excess, recently explained on the basis of mutations in the human 11 beta HSD2 gene, suggest that it is the 11 beta HSD2 isoform that serves a vital role in dictating specificity upon the mineralocorticoid receptor (MR). We have raised a novel antibody in sheep against human 11 beta HSD2 using synthetic multiantigenic peptides and have examined the localization and subcellular distribution of 11 beta HSD2 in mineralocorticoid target tissues. The immunopurified antibody recognized a single band of approximately 44 kDa in placenta, trophoblast, and distal colon. In kidney tissue, two bands of approximately 44 and 48 kDa were consistently observed. No signal was seen in decidua, adrenal, or liver. Immunoperoxidase studies on the mineralocorticoid target tissues, kidney, colon, and parotid gland indicated positive staining in epithelial cells known to express the MR: respectively, renal collecting ducts, surface and crypt colonic epithelial cells, and parotid duct epithelial cells. No staining was seen in these tissues in other sites. The intracellular localization of 11 beta HSD2 in kidney and colon epithelial cells was addressed using confocal laser microscopy. Parallel measurements of 11 beta HSD2 and nuclear propidium iodide fluorescence on sections scanned through an optical section of approximately 0.1 micron indicated significant 11 beta HSD2 immunofluorescence in the nucleus. In human kidney, colon, and salivary gland, 11 beta HSD2 protects the MR from glucocorticoid excess in an autocrine fashion. Furthermore, within these tissues, 11 beta HSD2, which had been considered to be a microsomal enzyme, is also found in the nucleus, suggesting that the

  16. Synovial tissue research

    DEFF Research Database (Denmark)

    Orr, Carl; Sousa, Elsa; Boyle, David L

    2017-01-01

    The synovium is the major target tissue of inflammatory arthritides such as rheumatoid arthritis. The study of synovial tissue has advanced considerably throughout the past few decades from arthroplasty and blind needle biopsy to the use of arthroscopic and ultrasonographic technologies that enable...... easier visualization and improve the reliability of synovial biopsies. Rapid progress has been made in using synovial tissue to study disease pathogenesis, to stratify patients, to discover biomarkers and novel targets, and to validate therapies, and this progress has been facilitated by increasingly...... diverse and sophisticated analytical and technological approaches. In this Review, we describe these approaches, and summarize how their use in synovial tissue research has improved our understanding of rheumatoid arthritis and identified candidate biomarkers that could be used in disease diagnosis...

  17. Layer-by-layer cell membrane assembly

    Science.gov (United States)

    Matosevic, Sandro; Paegel, Brian M.

    2013-11-01

    Eukaryotic subcellular membrane systems, such as the nuclear envelope or endoplasmic reticulum, present a rich array of architecturally and compositionally complex supramolecular targets that are as yet inaccessible. Here we describe layer-by-layer phospholipid membrane assembly on microfluidic droplets, a route to structures with defined compositional asymmetry and lamellarity. Starting with phospholipid-stabilized water-in-oil droplets trapped in a static droplet array, lipid monolayer deposition proceeds as oil/water-phase boundaries pass over the droplets. Unilamellar vesicles assembled layer-by-layer support functional insertion both of purified and of in situ expressed membrane proteins. Synthesis and chemical probing of asymmetric unilamellar and double-bilayer vesicles demonstrate the programmability of both membrane lamellarity and lipid-leaflet composition during assembly. The immobilized vesicle arrays are a pragmatic experimental platform for biophysical studies of membranes and their associated proteins, particularly complexes that assemble and function in multilamellar contexts in vivo.

  18. Remote Control of Tissue Interactions via Engineered Photo-switchable Cell Surfaces

    Science.gov (United States)

    Luo, Wei; Pulsipher, Abigail; Dutta, Debjit; Lamb, Brian M.; Yousaf, Muhammad N.

    2014-09-01

    We report a general cell surface molecular engineering strategy via liposome fusion delivery to create a dual photo-active and bio-orthogonal cell surface for remote controlled spatial and temporal manipulation of microtissue assembly and disassembly. Cell surface tailoring of chemoselective functional groups was achieved by a liposome fusion delivery method and quantified by flow cytometry and characterized by a new cell surface lipid pull down mass spectrometry strategy. Dynamic co-culture spheroid tissue assembly in solution and co-culture tissue multilayer assembly on materials was demonstrated by an intercellular photo-oxime ligation that could be remotely cleaved and disassembled on demand. Spatial and temporal control of microtissue structures containing multiple cell types was demonstrated by the generation of patterned multilayers for controlling stem cell differentiation. Remote control of cell interactions via cell surface engineering that allows for real-time manipulation of tissue dynamics may provide tools with the scope to answer fundamental questions of cell communication and initiate new biotechnologies ranging from imaging probes to drug delivery vehicles to regenerative medicine, inexpensive bioreactor technology and tissue engineering therapies.

  19. Efficient methods for targeted mutagenesis in zebrafish using zinc-finger nucleases: data from targeting of nine genes using CompoZr or CoDA ZFNs.

    Directory of Open Access Journals (Sweden)

    Raman Sood

    Full Text Available Recently, it has been shown that targeted mutagenesis using zinc-finger nucleases (ZFNs and transcription activator-like effector nucleases (TALENs can be used to generate knockout zebrafish lines for analysis of their function and/or developing disease models. A number of different methods have been developed for the design and assembly of gene-specific ZFNs and TALENs, making them easily available to most zebrafish researchers. Regardless of the choice of targeting nuclease, the process of generating mutant fish is similar. It is a time-consuming and multi-step process that can benefit significantly from development of efficient high throughput methods. In this study, we used ZFNs assembled through either the CompoZr (Sigma-Aldrich or the CoDA (context-dependent assembly platforms to generate mutant zebrafish for nine genes. We report our improved high throughput methods for 1 evaluation of ZFNs activity by somatic lesion analysis using colony PCR, eliminating the need for plasmid DNA extractions from a large number of clones, and 2 a sensitive founder screening strategy using fluorescent PCR with PIG-tailed primers that eliminates the stutter bands and accurately identifies even single nucleotide insertions and deletions. Using these protocols, we have generated multiple mutant alleles for seven genes, five of which were targeted with CompoZr ZFNs and two with CoDA ZFNs. Our data also revealed that at least five-fold higher mRNA dose was required to achieve mutagenesis with CoDA ZFNs than with CompoZr ZFNs, and their somatic lesion frequency was lower (<5% when compared to CopmoZr ZFNs (9-98%. This work provides high throughput protocols for efficient generation of zebrafish mutants using ZFNs and TALENs.

  20. Introduction to the ultrasound targeted microbubble destruction technique.

    Science.gov (United States)

    Walton, Chad B; Anderson, Cynthia D; Boulay, Rachel; Shohet, Ralph V

    2011-06-12

    In UTMD, bioactive molecules, such as negatively charged plasmid DNA vectors encoding a gene of interest, are added to the cationic shells of lipid microbubble contrast agents. In mice these vector-carrying microbubbles can be administered intravenously or directly to the left ventricle of the heart. In larger animals they can also be infused through an intracoronary catheter. The subsequent delivery from the circulation to a target organ occurs by acoustic cavitation at a resonant frequency of the microbubbles. It seems likely that the mechanical energy generated by the microbubble destruction results in transient pore formation in or between the endothelial cells of the microvasculature of the targeted region. As a result of this sonoporation effect, the transfection efficiency into and across the endothelial cells is enhanced, and transgene-encoding vectors are deposited into the surrounding tissue. Plasmid DNA remaining in the circulation is rapidly degraded by nucleases in the blood, which further reduces the likelihood of delivery to non-sonicated tissues and leads to highly specific target-organ transfection.