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Sample records for cells up-take cytocompatibility

  1. Investigation of interactions between poly-L-lysine-coated boron nitride nanotubes and C2C12 cells: up-take, cytocompatibility, and differentiation

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    G Ciofani

    2010-04-01

    Full Text Available G Ciofani1, L Ricotti1, S Danti2,3, S Moscato4, C Nesti2, D D’Alessandro2,4, D Dinucci5, F Chiellini5, A Pietrabissa3, M Petrini2,3, A Menciassi1,61Scuola Superiore Sant’Anna, Pisa, Italy; 2CUCCS-RRMR, Center for the Clinical Use of Stem Cells – Regional Network of Regenerative Medicine, 3Department of Oncology, Transplants and Advanced Technologies, 4Department of Human Morphology and Applied Biology, University of Pisa, Pisa, Italy; 5Laboratory of Bioactive Polymeric Materials for Biomedical and Environmental Applications (BIOlab, UdR INSTM, Department of Chemistry and Industrial Chemistry, University of Pisa, San Piero a Grado, Italy; 6Italian Institute of Technology, Genova, ItalyAbstract: Boron nitride nanotubes (BNNTs have generated considerable interest within the scientific community by virtue of their unique physical properties, which can be exploited in the biomedical field. In the present in vitro study, we investigated the interactions of poly-L-lysine-coated BNNTs with C2C12 cells, as a model of muscle cells, in terms of cytocompatibility and BNNT internalization. The latter was performed using both confocal and transmission electron microscopy. Finally, we investigated myoblast differentiation in the presence of BNNTs, evaluating the protein synthesis of differentiating cells, myotube formation, and expression of some constitutive myoblastic markers, such as MyoD and Cx43, by reverse transcription – polymerase chain reaction and Western blot analysis. We demonstrated that BNNTs are highly internalized by C2C12 cells, with neither adversely affecting C2C12 myoblast viability nor significantly interfering with myotube formation.Keywords: boron nitride nanotubes, C2C12 cells, cytocompatibility, up-take, differentiation, MyoD, connexin 43

  2. Bioinspired, cytocompatible mineralization of silica-titania composites: thermoprotective nanoshell formation for individual chlorella cells.

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    Ko, Eun Hyea; Yoon, Yeonjung; Park, Ji Hun; Yang, Sung Ho; Hong, Daewha; Lee, Kyung-Bok; Shon, Hyun Kyong; Lee, Tae Geol; Choi, Insung S

    2013-11-18

    Hard-shell case: Using a (RKK)4 D8 peptide allows mineralization to occur under cytocompatible conditions. Thus individual Chlorella cells could be encapsulated within a SiO2 -TiO2 nanoshell with high cell viability (87 %). The encapsulated Chlorella showed an almost threefold increase in their thermo-tolerance after 2 h at 45 °C.

  3. Cytocompatibility of Self-assembled Hydrogel from IKVAV-containing Peptide Amphiphile with Neural Stem Cells

    Institute of Scientific and Technical Information of China (English)

    SONG Yulin; ZHENG Qixin; GUO Xiaodong; ZHENG Jianfeng

    2009-01-01

    Neural Stem Cells(NSCs)were incubated with self-assembled hydrogel from IKVAV-containing peptide amphiphile(IKVAV-PA)for one week.The cytocompatibility of hydrogel was evaluated.NSCs were seeded in three-dimensional(3D)hydrogels(Experimental Group,EG)or surface of coverslips(Control Group,CG),double-labeled with Calcein-AM and PI.A growth curve of cells was obtained according to CCK-8.TEM study of hydrogel revealed a network of nanofibers. NSCs began to proliferate after 24 h of incubation,and formed bigger neurospheres at 48 h in EG than in CG.Cell proliferation activity was higher in EG than in CG(P<0.05).The self-assembled Hydrogel had good cytocompatibility and promoted the proliferation of NSCs.

  4. Cytocompatibility of HeLa Cells to Nano-Sized Ceramics Particles.

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    Seitoku, Eri; Abe, Shigeaki; Kusaka, Teruo; Nakamura, Mariko; Inoue, Satoshi; Yoshida, Yasuhiro; Sano, Hidehiko

    2016-04-01

    In this study, we investigated the behaviors and cytocompatibility response of human cervical carcinoma (HeLa) cells expose to nano-sized particles. Cultivated cells exposed to titanium oxide and indium oxide nanoparticles remained highly viable. In the presence of copper oxide (CuO); however, the cells became seriously inflamed. To understand the mechanism by which CuO causes cell death, we evaluated cell death and apoptosis cytometry. CuO induced cells apoptosis more strongly than exposure to titania nanoparticles. Confocal fluorescence microscopy revealed that the nano-sized particles penetrate the cells.

  5. Cytocompatibility of Three Corneal Cell Types with Amniotic Membrane

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    CHENJian-su; CHENRui; XUJin-tang; DINGYong; ZHAOSong-bin; LISui-lian

    2004-01-01

    Rabbit limbal corneal epithelial cells, corneal endothelial cells and keratocytes were cultured on amniotic membrane. Phase contrast microscope examination was performed daily. Histological and scan electron microscopic examinations were carried out to observe the growth, arrangement and adhesion of cultivated cells. Results showed that three corneal cell types seeded on amniotic membrane grew well and had normal cell morphology. Cultured cells attached firmly on the surface of amniotic membrane. Corneal epithelial cells showed singular layer or stratification. Cell boundaries were formed and tightly opposed. Corneal endothelial cells showed cobblestone or polygonal morphologic characteristics that appeared uniform in size. The cellular arrangement was compact. Keratocytes elongated and showed triangle or dendritic morphology with many intercellular joints which could form networks. In conclusion, amniotic membrane has good scaffold property, diffusion effect and compatibility with corneal cells. The basement membrane side of amniotic membrane facilitated the growth of corneal epithelial cells and endothelial cells and cell junctions were tightly developed. The spongy layer of amniotic membrane facilitated the growth of keratocytes and intercellular joints were rich. Amniotic membrane is an ideal biomaterial for layering tissue engineered cornea.

  6. Cytocompatible and multifunctional polymeric nanoparticles for transportation of bioactive molecules into and within cells

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    Ishihara, Kazuhiko; Chen, Weixin; Liu, Yihua; Tsukamoto, Yuriko; Inoue, Yuuki

    2016-01-01

    Abstract Multifunctional polymeric nanoparticles are materials with great potential for a wide range of biomedical applications. For progression in this area of research, unfavorable interactions of these nanoparticles with proteins and cells must be avoided in biological environments, for example, through treatment of the nanoparticle surfaces. Construction of an artificial cell membrane structure based on polymers bearing the zwitterionic phosphorylcholine group can prevent biological reactions at the surface effectively. In addition, certain bioactive molecules can be immobilized on the surface of the polymer to generate enough affinity to capture target biomolecules. Furthermore, entrapment of inorganic nanoparticles inside polymeric matrices enhances the nanoparticle functionality significantly. This review summarizes the preparation and characterization of cytocompatible and multifunctional polymeric nanoparticles; it analyzes the efficiency of their fluorescence function, the nature of the artificial cell membrane structure, and their performance as in-cell devices; and finally, it evaluates both their chemical reactivity and effects in cells. PMID:27877883

  7. Fabrication of silk mesh with enhanced cytocompatibility: preliminary in vitro investigation toward cell-based therapy for hernia repair.

    Science.gov (United States)

    Guillaume, O; Park, J; Monforte, X; Gruber-Blum, S; Redl, H; Petter-Puchner, A; Teuschl, A H

    2016-02-01

    Recent studies have demonstrated that combining cells with meshes prior to implantation successfully enhanced hernia repair. The idea is to create a biologic coating surrounding the mesh with autologous cells, before transplantation into the patient. However, due to the lack of a prompt and robust cell adhesion to the meshes, extensive in vitro cultivation is required to obtain a homogenous cell layer covering the mesh. In this context, the objective of this publication is to manufacture meshes made of silk fibres and to enhance the cytoadhesion and cytocompatibility of the biomaterial by surface immobilization of a pro-adhesive wheat germ agglutinin (lectin WGA). We first investigated the affinity between the glycoprotein WGA and cells, in solution and then after covalent immobilization of WGA on silk films. Then, we manufactured meshes made of silk fibres, tailored them with WGA grafting and finally evaluated the cytocompatibility and the inflammatory response of silk and silk-lectin meshes compared to common polypropylene mesh, using fibroblasts and peripheral blood mononuclear cells, respectively. The in vitro experiments revealed that the cytocompatibility of silk can be enhanced by surface immobilization with lectin WGA without exhibiting negative response in terms of pro-inflammatory reaction. Grafting lectin to silk meshes could bring advantages to facilitate cell-coating of meshes prior to implantation, which is an imperative prerequisite for abdominal wall tissue regeneration using cell-based therapy.

  8. Cytocompatibility of brushite and monetite cell culture scaffolds made by three-dimensional powder printing.

    Science.gov (United States)

    Klammert, U; Reuther, T; Jahn, C; Kraski, B; Kübler, A C; Gbureck, U

    2009-02-01

    This study investigated the cytocompatibility of low-temperature direct 3-D printed calcium phosphate scaffolds in vitro. The fabrication of the scaffolds was performed with a commercial 3-D powder printing system. Diluted phosphoric acid was printed into tricalcium phosphate powder, leading to the formation of dicalcium phosphate dihydrate (brushite). Hydrothermal conversion of the brushite matrices led to the formation of dicalcium phosphate anhydrous (monetite). The biocompatibility was investigated using the osteoblastic cell line MC3T3-E1. Cell viability and the expression of alkaline phosphatase served as parameters. The culture medium was analyzed for pH value, concentration of free calcium and phosphate ions and osteocalcin. Both types of scaffolds showed a considerable increase of cell proliferation and viability; the monetite matrices were a little inferior compared with the brushite ones. The activity of alkaline phosphatase showed a similar pattern. Optical and electron microscopy revealed an obvious cell growth on the surface of both materials. Analysis of the culture medium showed minor alterations of pH value within the physiological range. The concentrations of free calcium and phosphate ions were obviously different among brushite and monetite cultures, due to their different solubility. The content of osteocalcin of the culture medium was reduced by the printed scaffolds due to adsorption. We conclude that the powder printed brushite and monetite matrices have a suitable biocompatibility for their use as cell culture scaffolds. Both materials enable osteoblastic cells in vitro to proliferate and differentiate due to the expression of typical osteoblastic markers.

  9. A Comparative Study on Root Canal Repair Materials: A Cytocompatibility Assessment in L929 and MG63 Cells

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    Yuqing Jiang

    2014-01-01

    Full Text Available Cytocompatibility of repair materials plays a significant role in the success of root canal repair. We conducted a comparative study on the cytocompatibility among iRoot BP Plus, iRoot FS, ProRoot MTA, and Super-EBA in L929 cells and MG63 cells. The results revealed that iRoot FS was able to completely solidify within 1 hour. iRoot BP Plus required 7-day incubation, which was much longer than expected (2 hours, to completely set. ProRoot MTA and Super-EBA exhibited a similar setting duration of 12 hours. All the materials except Super-EBA possessed negligible in vitro cytotoxicity. iRoot FS had the best cell adhesion capacity in both L929 and MG63 cells. With rapid setting, negligible cytotoxicity, and enhanced cell adhesion capacity, iRoot FS demonstrated great potential in clinical applications. Future work should focus on longer-term in vitro cytocompatibility and an in vivo assessment.

  10. Cytocompatible biointerface on poly(lactic acid) by enrichment with phosphorylcholine groups for cell engineering

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    Watanabe, Junji [Department of Materials Engineering, School of Engineering, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Nederberg, Fredrik [Department of Materials Chemistry, Angstroem Laboratory, Uppsala University, Uppsala S-751 21 (Sweden); Atthoff, Bjoern [Department of Materials Chemistry, Angstroem Laboratory, Uppsala University, Uppsala S-751 21 (Sweden); Bowden, Tim [Department of Materials Chemistry, Angstroem Laboratory, Uppsala University, Uppsala S-751 21 (Sweden); Hilborn, Joens [Department of Materials Chemistry, Angstroem Laboratory, Uppsala University, Uppsala S-751 21 (Sweden); Ishihara, Kazuhiko [Department of Materials Engineering, School of Engineering, University of Tokyo, 7-3-1, Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan)]. E-mail: ishihara@mpc.t.u-tokyo.ac.jp

    2007-03-15

    A tunable biointerface was designed and prepared using a novel biocompatible phospholipid polymer composed of 2-methacryloyloxyethyl phosphorylcholine (MPC), n-butyl methacrylate, and isomeric poly(lactic acid) macromonomer. The phospholipid polymer was coated on a substrate, and the surface characterization was examined in terms of surface elemental analysis by X-ray photoelectron spectroscopy and dynamic contact angle measurements. The phosphorylcholine (PC) group in the MPC units was enriched after immersion in a buffer solution following heating above its glass transition temperature. After the enrichment of the phosphorylcholine group, the surface wettability was significantly improved and the adsorption behavior of serum proteins was investigated. Albumin and {gamma}-globulin hardly adsorbed on the polymer surface as a result of the surface enriched PC group. On the other hand, adsorption of fibrinogen, which is a cell adhesive protein, was maintained at almost the same level as that from the dry surface. As a result the biointerface on the substrate had dual functions, cytocompatibility by a reduction of the general protein adsorption and cell adhesivity based on the adsorption of fibrinogen. The material duality provides for a tunable biointerface and thus an interesting candidate for cell engineering is formed.

  11. Cytocompatibility of direct water synthesized cadmium selenide quantum dots in colo-205 cells

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    Rodriguez-Torres, Marcos R.; Velez, Christian; Zayas, Beatriz; Rivera, Osvaldo; Arslan, Zikri; Gonzalez-Vega, Maxine N.; Diaz-Diestra, Daysi; Beltran-Huarac, Juan; Morell, Gerardo; Primera-Pedrozo, Oliva M.

    2015-06-01

    Cadmium selenide quantum dots (CdSe QDs), inorganic semiconducting nanocrystals, are alluring increased attraction due to their highly refined chemistry, availability, and super tunable optical properties suitable for many applications in different research areas, such as photovoltaics, light-emitting devices, environmental sciences, and nanomedicine. Specifically, they are being widely used in bio-imaging in contrast to organic dyes due to their high brightness and improved photo-stability, and their ability to tune their absorption and emission spectra upon changing the crystal size. The production of CdSe QDs is mostly assisted by trioctylphosphine oxide compound, which acts as solvent or solubilizing agent and renders the QDs soluble in organic compounds (such as toluene, chloroform, and hexane) that are highly toxic. To circumvent the toxicity-related factor in CdSe QDs, we report the synthesis of CdSe QDs capped with thioglycolic acid (TGA) in an aqueous medium, and their biocompatibility in colo-205 cancer cells. In this study, the [Cd2+]/[TGA] ratio was adjusted to 11:1 and the Se concentration (10 and 15 mM) was monitored in order to evaluate its influence on the optical properties and cytocompatibility. QDs resulted to be quite stable in water (after purification) and RPMI cell medium and no precipitation was observed for long contact times, making them appealing for in vitro experiments. The spectroscopy analysis, advanced electron microscopy, and X-ray diffractometry studies indicate that the final products were successfully formed exhibiting an improved optical response. Colo-205 cells being exposed to different concentrations of TGA-capped CdSe QDs for 12, 24, and 48 h with doses ranging from 0.5 to 2.0 mM show high tolerance reaching cell viabilities as high as 93 %. No evidence of cellular apoptotic pathways was observed as pointed out by our Annexin V assays at higher concentrations. Moreover, confocal microscopy analysis conducted to evaluate the

  12. Cytocompatibility of direct water synthesized cadmium selenide quantum dots in colo-205 cells

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    Rodriguez-Torres, Marcos R. [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States); Velez, Christian; Zayas, Beatriz [Universidad Metropolitana, ChemTox Laboratory, School of Environmental Affairs (United States); Rivera, Osvaldo [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States); Arslan, Zikri [Jackson State University, Department of Chemistry (United States); Gonzalez-Vega, Maxine N. [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States); Diaz-Diestra, Daysi; Beltran-Huarac, Juan; Morell, Gerardo [University of Puerto Rico, Molecular Science Research Center (United States); Primera-Pedrozo, Oliva M., E-mail: oprimera1@suagm.edu [Universidad Metropolitana, Nanomaterials Science Laboratory, School of Science and Technology (United States)

    2015-06-15

    Cadmium selenide quantum dots (CdSe QDs), inorganic semiconducting nanocrystals, are alluring increased attraction due to their highly refined chemistry, availability, and super tunable optical properties suitable for many applications in different research areas, such as photovoltaics, light-emitting devices, environmental sciences, and nanomedicine. Specifically, they are being widely used in bio-imaging in contrast to organic dyes due to their high brightness and improved photo-stability, and their ability to tune their absorption and emission spectra upon changing the crystal size. The production of CdSe QDs is mostly assisted by trioctylphosphine oxide compound, which acts as solvent or solubilizing agent and renders the QDs soluble in organic compounds (such as toluene, chloroform, and hexane) that are highly toxic. To circumvent the toxicity-related factor in CdSe QDs, we report the synthesis of CdSe QDs capped with thioglycolic acid (TGA) in an aqueous medium, and their biocompatibility in colo-205 cancer cells. In this study, the [Cd{sup 2+}]/[TGA] ratio was adjusted to 11:1 and the Se concentration (10 and 15 mM) was monitored in order to evaluate its influence on the optical properties and cytocompatibility. QDs resulted to be quite stable in water (after purification) and RPMI cell medium and no precipitation was observed for long contact times, making them appealing for in vitro experiments. The spectroscopy analysis, advanced electron microscopy, and X-ray diffractometry studies indicate that the final products were successfully formed exhibiting an improved optical response. Colo-205 cells being exposed to different concentrations of TGA-capped CdSe QDs for 12, 24, and 48 h with doses ranging from 0.5 to 2.0 mM show high tolerance reaching cell viabilities as high as 93 %. No evidence of cellular apoptotic pathways was observed as pointed out by our Annexin V assays at higher concentrations. Moreover, confocal microscopy analysis conducted to

  13. Coatings of Different Carbon Nanotubes on Platinum Electrodes for Neuronal Devices: Preparation, Cytocompatibility and Interaction with Spiral Ganglion Cells.

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    Niklas Burblies

    Full Text Available Cochlear and deep brain implants are prominent examples for neuronal prostheses with clinical relevance. Current research focuses on the improvement of the long-term functionality and the size reduction of neural interface electrodes. A promising approach is the application of carbon nanotubes (CNTs, either as pure electrodes but especially as coating material for electrodes. The interaction of CNTs with neuronal cells has shown promising results in various studies, but these appear to depend on the specific type of neurons as well as on the kind of nanotubes. To evaluate a potential application of carbon nanotube coatings for cochlear electrodes, it is necessary to investigate the cytocompatibility of carbon nanotube coatings on platinum for the specific type of neuron in the inner ear, namely spiral ganglion neurons. In this study we have combined the chemical processing of as-delivered CNTs, the fabrication of coatings on platinum, and the characterization of the electrical properties of the coatings as well as a general cytocompatibility testing and the first cell culture investigations of CNTs with spiral ganglion neurons. By applying a modification process to three different as-received CNTs via a reflux treatment with nitric acid, long-term stable aqueous CNT dispersions free of dispersing agents were obtained. These were used to coat platinum substrates by an automated spray-coating process. These coatings enhance the electrical properties of platinum electrodes, decreasing the impedance values and raising the capacitances. Cell culture investigations of the different CNT coatings on platinum with NIH3T3 fibroblasts attest an overall good cytocompatibility of these coatings. For spiral ganglion neurons, this can also be observed but a desired positive effect of the CNTs on the neurons is absent. Furthermore, we found that the well-established DAPI staining assay does not function on the coatings prepared from single-wall nanotubes.

  14. Essential Oil from Berries of Lebanese Juniperus excelsa M. Bieb Displays Similar Antibacterial Activity to Chlorhexidine but Higher Cytocompatibility with Human Oral Primary Cells

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    Barbara Azzimonti

    2015-05-01

    Full Text Available Chlorhexidine (CHX, one of the most effective drugs administered for periodontal treatment, presents collateral effects including toxicity when used for prolonged periods; here, we have evaluated the bactericidal potency and the cytocompatibility of Juniperus excelsa M. Bieb essential oil (EO in comparison with 0.05% CHX. The EO was extracted from berries by hydrodistillation and components identified by gas chromatography and mass spectrometry. Bacterial inhibition halo analysis, quantitative cell viability 2,3-bis(2-methoxy-4-nitro-5-sulphophenyl-5-[(phenyl amino carbonyl]-2H-tetrazolium hydroxide assay (XTT, and colony forming unit (CFU count were evaluated against the two biofilm formers Aggregatibacter actinomycetemcomitans and Streptococcus mutans. Finally, cytocompatibility was assessed with human primary gingival fibroblasts (HGF and mucosal keratinocytes (HK. The resulting EO was mainly composed of monoterpene hydrocarbons and oxygenated monoterpenes. An inhibition halo test demonstrated that both bacteria were sensitive to the EO; XTT analysis and CFU counts confirmed that 10-fold-diluted EO determined a statistically significant (p < 0.05 reduction in bacteria count and viability towards both biofilm and planktonic forms in a comparable manner to those obtained with CHX. Moreover, EO displayed higher cytocompatibility than CHX (p < 0.05. In conclusion, EO exhibited bactericidal activity similar to CHX, but a superior cytocompatibility, making it a promising antiseptic alternative to CHX.

  15. Cytocompatibility and Antibacterial Properties of Capping Materials

    Science.gov (United States)

    Arciola, Carla Renata; Monaco, Annachiara; Lombardini, Marco

    2014-01-01

    The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply), Calcicur (Voco), Calcimol LC (Voco), TheraCal LC (Bisco), MTA Angelus (Angelus), and Biodentine (Septodont). To evaluate antimicrobial activity, materials were challenged in vitro with Streptococcus mutans, Streptococcus salivarius, and Streptococcus sanguis in the agar disc diffusion test. Cytocompatibility of the assayed materials towards rat MDPC-23 cells was evaluated at different times by both MTT and apoptosis assays. Results significantly differed among the different materials tested. Both bacterial growth inhibition halos and cytocompatibility performances were significantly different among materials with different composition. MTA-based products showed lower cytotoxicity and valuable antibacterial activity, different from calcium hydroxide-based materials, which exhibited not only higher antibacterial activity but also higher cytotoxicity. PMID:24959601

  16. Cytocompatibility and Antibacterial Properties of Capping Materials

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    Claudio Poggio

    2014-01-01

    Full Text Available The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply, Calcicur (Voco, Calcimol LC (Voco, TheraCal LC (Bisco, MTA Angelus (Angelus, and Biodentine (Septodont. To evaluate antimicrobial activity, materials were challenged in vitro with Streptococcus mutans, Streptococcus salivarius, and Streptococcus sanguis in the agar disc diffusion test. Cytocompatibility of the assayed materials towards rat MDPC-23 cells was evaluated at different times by both MTT and apoptosis assays. Results significantly differed among the different materials tested. Both bacterial growth inhibition halos and cytocompatibility performances were significantly different among materials with different composition. MTA-based products showed lower cytotoxicity and valuable antibacterial activity, different from calcium hydroxide-based materials, which exhibited not only higher antibacterial activity but also higher cytotoxicity.

  17. Highly cytocompatible and flexible three-dimensional graphene/polydimethylsiloxane composite for culture and electrochemical detection of L929 fibroblast cells.

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    Waiwijit, Uraiwan; Maturos, Thitima; Pakapongpan, Saithip; Phokharatkul, Ditsayut; Wisitsoraat, Anurat; Tuantranont, Adisorn

    2016-08-01

    Recently, three-dimensional graphene interconnected network has attracted great interest as a scaffold structure for tissue engineering due to its high biocompatibility, high electrical conductivity, high specific surface area and high porosity. However, free-standing three-dimensional graphene exhibits poor flexibility and stability due to ease of disintegration during processing. In this work, three-dimensional graphene is composited with polydimethylsiloxane to improve the structural flexibility and stability by a new simple two-step process comprising dip coating of polydimethylsiloxane on chemical vapor deposited graphene/Ni foam and wet etching of nickel foam. Structural characterizations confirmed an interconnected three-dimensional multi-layer graphene structure with thin polydimethylsiloxane scaffold. The composite was employed as a substrate for culture of L929 fibroblast cells and its cytocompatibility was evaluated by cell viability (Alamar blue assay), reactive oxygen species production and vinculin immunofluorescence imaging. The result revealed that cell viability on three-dimensional graphene/polydimethylsiloxane composite increased with increasing culture time and was slightly different from a polystyrene substrate (control). Moreover, cells cultured on three-dimensional graphene/polydimethylsiloxane composite generated less ROS than the control at culture times of 3-6 h. The results of immunofluorescence staining demonstrated that fibroblast cells expressed adhesion protein (vinculin) and adhered well on three-dimensional graphene/polydimethylsiloxane surface. Good cell adhesion could be attributed to suitable surface properties of three-dimensional graphene/polydimethylsiloxane with moderate contact angle and small negative zeta potential in culture solution. The results of electrochemical study by cyclic voltammetry showed that an oxidation current signal with no apparent peak was induced by fibroblast cells and the oxidation current at an

  18. Differences in cytocompatibility between collagen, gelatin and keratin

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    Wang, Yanfang; Zhang, Weiwei; Yuan, Jiang, E-mail: jyuan@njnu.edu.cn; Shen, Jian, E-mail: jshen@njnu.edu.cn

    2016-02-01

    Keratins are cysteine-rich intermediate filament proteins found in the cytoskeleton of the epithelial cells and in the matrix of hair, feathers, wool, nails and horns. The natural abundance of cell adhesion sequences, RGD (Arg-Gly-Asp) and LDV (Leu-Asp-Val), makes them suitable for tissue engineering applications. The purpose of our study is to evaluate their cytocompatibility as compared to well-known collagen and gelatin proteins. Herein, collagen, gelatin and keratin were blended with poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) and electrospun to afford nanofibrous mats, respectively. These PHBV/protein composite mats were characterized by field emission scanning electron microscopy (FE-SEM), attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS), and dynamic mechanical analysis (DMA). The cytocompatibility was evaluated with cell adhesion, cell viability and cell proliferation. The data from MTT and BrDU revealed that collagen had significantly superior cytocompatibility as compared to gelatin and keratin. Gelatin showed a better cytocompatibility than keratin without statistical significance difference. Finally, we gave the reasons to account for the above conclusions. - Highlights: • Collagen, gelatin and keratin were coelectrospun with PHBV to afford nanofibrous mats. • Cytocompatibility was evaluated with cell adhesion, cell viability and cell proliferation. • Collagen had significantly superior cytocompatibility as compared to gelatin and keratin.

  19. Immobilization of biomacromolecules on poly-L-lactide surface via a layer-by-layer method for the improving of its cytocompatibility to bone marrow stromal cells

    Institute of Scientific and Technical Information of China (English)

    L(U) Delong; MENG Sheng; ZHONG Wei; DU Qiangguo; GONG Li; LIU Jinfen; Dusan Bakos

    2005-01-01

    Hyaluronic acid (HA) and chitosan (CS) were immobilized on the surface of poly-L-lactide (PLLA) by the following procedure: Firstly, PLLA was aminolyzed with 1, 6-hexanediamine, and part of the PLLA surface ester groups were converted to free amino groups. Then negatively charged hyaluronic acid and positively charged chitosan were deposited onto the surface of aminolyzed PLLA film in a layer-by-layer assembly manner. The effect of the layer-by- layer deposition was evaluated by ATR-FTIR spectroscopy, Raman spectroscopy and static contact angle measurements. The cytocompatibility of PLLA sample to bone marrow stromal cells (BMSCs) was improved after modification with chitosan and HA. The cell attachment, activity, and proliferation on CS/HA modified PLLA films were enhanced comparing with the control. The cells cultured on the modified PLLA samples excreted abundant cytoplasm and can differentiate to vascular smooth muscle (SM)-like (SM-like) cells. A macroporous three-dimensional PLLA scaffold was prepared by integrating both the technique of freeze-drying and particle leaching. Layer-by-layer modification by HA/CS and cell culture was also applied on this scaffold. The scaffold cultured with BMSCs for 2 weeks has been tested successfully in vivo as a patch for repairing the artificial incision on canine pulmonary artery.

  20. Cytocompatibility of High Nitrogen Nickel-Free Stainless Steel for Orthopedic Implants

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    Tianchi Ma; Peng Wan; Yuyan Cui; Guirong Zhang; Jiqiang Li; Jihui Liu; Yibin Ren; Ke Yangg; Li Lu

    2012-01-01

    Cytocompatibility of high nitrogen nickel-free stainless steel (HNS) with different nitrogen content was evalu- ated and compared with a conventional austenitic stainless steel 317L. The MTT assay (3-(4,5-dimethylthiazol- 2-yl)-2,5-diphenyltetrazolium bromide) was performed on MG63 osteoblasts to assess the cytotoxicity. The expression of selected marker typical of differentiated osteoblasts, such as alkaline phosphatase activity (AKP), was also monitored in MG63 cells cultured on the tested materials. As a result, HNS had higher cell growth than 317L; meanwhile the cytocompatibility was increased with increasing nitrogen content. Furthermore, HNS enhanced osteoblasts differentiation, as confirmed by AKP activity. Overall these facts indicated that HNS had higher cytocompatibility than 317L and the nitrogen content contributed to the higher cytocompatibility of HNS. The influence of nitrogen on surface energy further explained the cytocompatibility of HNS.

  1. Characterization of mechanics and cytocompatibility of fibrin-genipin annulus fibrosus sealant with the addition of cell adhesion molecules.

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    Guterl, Clare C; Torre, Olivia M; Purmessur, Devina; Dave, Khyati; Likhitpanichkul, Morakot; Hecht, Andrew C; Nicoll, Steven B; Iatridis, James C

    2014-09-01

    There is an unmet clinical need for a biomaterial sealant capable of repairing small annulus fibrosus (AF) defects. Causes of these defects include painful intervertebral disc herniations, microdiscectomy procedures, morbidity associated with needle puncture injury from discography, and future nucleus replacement procedures. This study describes the enhancements of a fibrin gel through genipin crosslinking (FibGen) and the addition of the cell adhesion molecules (CAMs), fibronectin and collagen. The gel's performance as a potential AF sealant is assessed using a series of in vitro tests. FibGen gels with CAMs had equivalent adhesive strength, gene expression, cytomorphology, and cell proliferation as fibrin alone. However, FibGen gels had enhanced material behaviors that were tunable to higher shear stiffness values and approximated human annulus tissue as compared with fibrin alone, were more dimensionally stable, and had a slower in vitro degradation rate. Cytomorphology of human AF cells cultured on FibGen gels exhibited increased elongation compared with fibrin alone, and the addition of CAMs to FibGen did not significantly affect elongation. This FibGen gel offers the promise of being used as a sealant material to repair small AF defects or to be used in combination with other biomaterials as an adhesive for larger defects.

  2. The Preparation and Cytocompatibility of Injectable Thermosensitive Chitosan/Poly(vinyl alcohol) Hydrogel

    Institute of Scientific and Technical Information of China (English)

    漆白文; 喻爱喜; 祝少博; 陈彪; 李艳

    2010-01-01

    In order to investigate the strength,structure and cell cytocompatibility of injectable thermosensitive chitosan(CS)/poly(vinyl alcohol)(PVA)composite hydrogel,chitosan hydrochloride solution was transferred to a neutral pH and mixed with different proportions of PVA,then the gelation time and strength of these different hydrogels were tested and spatial structures were observed under a scanning electron microscopy(SEM)after freeze-drying.The cytocompatibility of the hydrogels was evaluated through cytotoxi...

  3. Cytocompatibility and Antibacterial Properties of Capping Materials

    OpenAIRE

    Claudio Poggio; Carla Renata Arciola; Riccardo Beltrami; Annachiara Monaco; Alberto Dagna; Marco Lombardini; Livia Visai

    2014-01-01

    The aim of this study was to evaluate and compare the antimicrobial activity and cytocompatibility of six different pulp-capping materials: Dycal (Dentsply), Calcicur (Voco), Calcimol LC (Voco), TheraCal LC (Bisco), MTA Angelus (Angelus), and Biodentine (Septodont). To evaluate antimicrobial activity, materials were challenged in vitro with Streptococcus mutans, Streptococcus salivarius, and Streptococcus sanguis in the agar disc diffusion test. Cytocompatibility of the assayed materials towa...

  4. Cytocompatible cellulose hydrogels containing trace lignin.

    Science.gov (United States)

    Nakasone, Kazuki; Kobayashi, Takaomi

    2016-07-01

    Sugarcane bagasse was used as a cellulose resource to prepare transparent and flexible cellulose hydrogel films. On the purification process from bagasse to cellulose, the effect of lignin residues in the cellulose was examined for the properties and cytocompatibility of the resultant hydrogel films. The cellulose was dissolved in lithium chloride/N,N-dimethylacetamide solution and converted to hydrogel films by phase inversion. In the purification process, sodium hydroxide (NaOH) treatment time was changed from 1 to 12h. This resulted in cellulose hydrogel films having small amounts of lignin from 1.62 to 0.68%. The remaining lignin greatly affected hydrogel properties. Water content of the hydrogel films was increased from 1153 to 1525% with a decrease of lignin content. Moreover, lower lignin content caused weakening of tensile strength from 0.80 to 0.43N/mm(2) and elongation from 45.2 to 26.5%. Also, similar tendency was observed in viscoelastic behavior of the cellulose hydrogel films. Evidence was shown that the lignin residue was effective for the high strength of the hydrogel films. In addition, scanning probe microscopy in the morphological observation was suggested that the trace lignin in the cellulose hydrogel affected the cellulose fiber aggregation in the hydrogel network. The trace of lignin in the hydrogels also influenced fibroblast cell culture on the hydrogel films. The hydrogel film containing 1.68% lignin showed better fibroblast compatibility as compared to cell culture polystyrene dish used as reference.

  5. Preparation and cytocompatibility of silk fibroin /chitosan scaffolds

    Institute of Scientific and Technical Information of China (English)

    Zhen-ding SHE; Wei-qiang LIU; Qing-ling FENG

    2009-01-01

    One challenge in soft tissue engineering is to find an applicable scaffold, not only having suitable mechanical properties, porous structures, and biodegradable properties, but also being abundant in active groups and having good biocompatibility. In this study, a threedimensional silk fibroin/chitosan (SFCS) scaffold was successfully prepared with interconnected porous structure, excellent hydrophilicity, and proper mechanical properties. Compared with polylactic glycolic acid (PLGA) scaffold, the SFCS scaffold further facilitated the growth of HepG2 cells (human hepatoma cell line). Keeping the good cytocompatibility and combining the advantages of both fibroin and chitosan, the SFCS scaffold should be a prominent candidate for soft tissue engineering, for example, liver.

  6. Surface characterization and cytocompatibility evaluation of silanized magnesium alloy AZ91 for biomedical applications

    Science.gov (United States)

    Witecka, Agnieszka; Yamamoto, Akiko; Dybiec, Henryk; Swieszkowski, Wojciech

    2012-12-01

    Mg alloys with high Al contents have superior corrosion resistance in aqueous environments, but poor cytocompatibility compared to that of pure Mg. We have silanized the cast AZ91 alloy to improve its cytocompatibility using five different silanes: ethyltriethoxysilane (S1), 3-aminopropyltriethoxysilane (S2), 3-isocyanatopyltriethoxysilane (S3), phenyltriethoxysilane (S4) and octadecyltriethoxysilane (S5). The surface hydrophilicity/hydrophobicity was evaluated by water contact angle measurements. X-ray photoelectron analysis was performed to investigate the changes in surface states and chemical composition. All silane reagents increased adsorption of the albumin to the modified surface. In vitro cytocompatibility evaluation revealed that silanization improved cell growth on AZ91 modified by silane S1. Measurement of the concentration of Mg2+ ions released during the cell culture indicated that silanization does not affect substrate degradation.

  7. Surface characterization and cytocompatibility evaluation of silanized magnesium alloy AZ91 for biomedical applications

    Directory of Open Access Journals (Sweden)

    Agnieszka Witecka, Akiko Yamamoto, Henryk Dybiec and Wojciech Swieszkowski

    2012-01-01

    Full Text Available Mg alloys with high Al contents have superior corrosion resistance in aqueous environments, but poor cytocompatibility compared to that of pure Mg. We have silanized the cast AZ91 alloy to improve its cytocompatibility using five different silanes: ethyltriethoxysilane (S1, 3-aminopropyltriethoxysilane (S2, 3-isocyanatopyltriethoxysilane (S3, phenyltriethoxysilane (S4 and octadecyltriethoxysilane (S5. The surface hydrophilicity/hydrophobicity was evaluated by water contact angle measurements. X-ray photoelectron analysis was performed to investigate the changes in surface states and chemical composition. All silane reagents increased adsorption of the albumin to the modified surface. In vitro cytocompatibility evaluation revealed that silanization improved cell growth on AZ91 modified by silane S1. Measurement of the concentration of Mg2+ ions released during the cell culture indicated that silanization does not affect substrate degradation.

  8. Chemically crosslinked nanogels of PEGylated poly ethyleneimine (L-histidine substituted) synthesized via metal ion coordinated self-assembly for delivery of methotrexate: Cytocompatibility, cellular delivery and antitumor activity in resistant cells

    Energy Technology Data Exchange (ETDEWEB)

    Abolmaali, Samira Sadat, E-mail: s.abolmaali@gmail.com [Pharmaceutical Nanotechnology Department, Shiraz University of Medical Sciences, Shiraz 71345 (Iran, Islamic Republic of); Tamaddon, Ali Mohammad, E-mail: amtamadon@gmail.com [Center for Nanotechnology in Drug Delivery, Shiraz University of Medical Sciences, Shiraz 71345 (Iran, Islamic Republic of); Mohammadi, Samaneh, E-mail: samaneh.mohammadi1986@gmail.com [Center for Nanotechnology in Drug Delivery, Shiraz University of Medical Sciences, Shiraz 71345 (Iran, Islamic Republic of); Amoozgar, Zohreh, E-mail: zohreh_amoozgar@dfci.harvard.edu [Department of Cancer Immunology and Aids, Dana-Farber Cancer Institute and Harvard Medical School, Boston, MA 02115 (United States); Dinarvand, Rasoul, E-mail: dinarvand@tums.ac.ir [Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran 14174 (Iran, Islamic Republic of)

    2016-05-01

    Self-assembled nanogels were engineered by forming Zn{sup 2+}-coordinated micellar templates of PEGylated poly ethyleneimine (PEG-g-PEI), chemical crosslinking and subsequent removal of the metal ion. Creation of stable micellar templates is a crucial step for preparing the nanogels. To this aim, imidazole moieties were introduced to the polymer by Fmoc-L-histidine using carbodiimide chemistry. It was hypothesized the nanogels loaded with methotrexate (MTX), a chemotherapeutic agent, circumvent impaired carrier activity in HepG2 cells (MTX-resistant hepatocellular carcinoma). So, the nanogels were post-loaded with MTX and characterized by {sup 1}H-NMR, FTIR, dynamic light scattering-zeta potential, atomic force microscopy, and drug release experiments. Cellular uptake and the antitumor activity of MTX-loaded nanogels were investigated by flow cytometry and MTT assay. Discrete, spherical and uniform nanogels, with sizes about 77–83 nm and a relatively high drug loading (54 ± 4% w/w), showed a low polydispersity and neutral surface charges. The MTX-loaded nanogels, unlike empty nanogels, lowered viability of HepG2 cells; the nanogels demonstrated cell-cycle arrest and apoptosis comparably higher than MTX as free drug that was shown to be through i) cellular uptake of the nanogels by clathrin-mediated transport and ii) endosomolytic activity of the nanogels in HepG2 cells. These findings indicate the potential antitumor application of this preparation, which has to be investigated in-vivo. - Highlights: • Nanogel synthesis through chemical crosslinking of the transition metal ion coordinated polymer self-assembly • An enhanced cytocompatibility if compared to unmodified polymer • A noticeable endocytic cellular internalization and endosomolytic activity • A specific antitumor cytotoxicity, cell cycle arrest and apoptosis in resistant tumor cells.

  9. Cytocompatibility of amine functionalized carbon nanoparticles grafted on polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Žáková, Pavlína, E-mail: pavlina.zakova@vscht.cz [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic); Slepičková Kasálková, Nikola [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic); Kolská, Zdeňka [Faculty of Science, J. E. Purkyně University, Ústí nad Labem (Czech Republic); Leitner, Jindřich [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic); Karpíšková, Jana; Stibor, Ivan [Institute for Nanomaterials, Advanced Technologies and Innovation, Technical University of Liberec (Czech Republic); Slepička, Petr; Švorčík, Václav [Department of Solid State Engineering, University of Chemistry and Technology, 166 28 Prague 6 (Czech Republic)

    2016-03-01

    Five types of amide–amine Carbon Nano-Particles (CNPs) were prepared by functionalization of CNPs and characterized by several analytical methods. The successful grafting of amines on CNPs was verified by X-ray photoelectron spectroscopy (XPS), organic elemental analysis and electrokinetic analysis. The size and morphology of CNPs were determined from transmission electron microscopy. The surface area and porosity of CNPs were examined by adsorption and desorption isotherms. Differential scanning calorimetry was used to investigate thermal stability of CNPs. The amount of bonded amine depends on its dimensionality arrangement. Surface area and pore volumes of CNPs decrease several times after individual amino-compound grafting. Selected types of functionalized CNPs were grafted onto a plasma activated surface of HDPE. The successful grafting of CNPs on the polymer surface was verified by XPS. Wettability was determined by contact angle measurements. Surface morphology and roughness were studied by atomic force microscopy. A dramatic decrease of contact angle and surface morphology was observed on CNP grafted polymer surface. Cytocompatibility of modified surfaces was studied in vitro, by determination of adhesion, proliferation and viability of vascular smooth muscle cells (VSMCs). Grafting of CNPs onto the polymer surface has a positive effect on the adhesion, proliferation and viability of VSMCs. - Highlights: • Amine functionalized CNPs were successfully grafted on HDPE surface. • Significant change to the positive zeta potential for grafted CNPs was induced. • Grafting of CNPs significantly enhanced cell cytocompatibility and viability. • Homogeneous distribution of cells with correct size was achieved.

  10. Cure Behaviors and Water Up-take Evaluation of a New Waterborne Epoxy Resin

    Institute of Scientific and Technical Information of China (English)

    WAN Tao; ZANG Tianshun; ZHANG Rui; SUN Xianchang

    2012-01-01

    Cure behaviors and water up-take evaluation of a low cost,ecofriendly and water soluble epoxy resin prepared by reaction between epichlorohydrin and PEG400,PEG600 and PEG1000,respectively,were investigated using non-isothermal differential scanning calorimetry (DSC) and gravimetrical method,respectively.Factors affecting the cure behaviors as well as water up-take of waterborne epoxy resins,such as amount of triethylenetetramine (TETA) and triethylene diamine (TEDA),PEG molecular weight,curing temperature,were systematically investigated.The prepared water soluble epoxy resins can be cured under room temperature with the shape of the curing curves similar to that expected for an autocatalytic reaction.

  11. Characteristics and cytocompatibility of biodegradable polymer film on magnesium by spin coating.

    Science.gov (United States)

    Xu, Liping; Yamamoto, Akiko

    2012-05-01

    In recent years, magnesium and its alloys have been investigated as biodegradable metallic materials in cardiovascular stents and bone implants. However, rapid corrosion rate in the early stage of the degradation process greatly influences the cytocompatibility and hinters their application. In this research, biodegradable polymer films are prepared under same coating condition by spin coating in order to improve the early corrosion resistance and cytocompatibility of Mg. The results present that uniform, nonporous, amorphous PLLA and semi-crystalline PCL films are coated on Mg. PLLA film shows better adhesion strength to Mg substrate than that of PCL film. For both PLLA and PCL, low molecular weight (LMW) film is thinner and exhibits better adhesion strength than high molecular weight (HMW) one. SaOS-2 cells show significantly good attachment and high growth on the polymer-coated Mg, demonstrating that all the polymer films can significantly improve the cytocompatibility in the 7-day incubation. The pH measurement of the immersion medium and the quantification of released Mg(2+) during the cell culture clearly indicate that the corrosion resistance of Mg substrate is improved by the polymer films to different extents. It can be concluded that both PLLA and PCL films are promising protective coatings for improving the initial corrosion resistance and cytocompatibility.

  12. Biofunctionalization of microgroove titanium surfaces with an antimicrobial peptide to enhance their bactericidal activity and cytocompatibility.

    Science.gov (United States)

    Zhou, Lin; Lai, Yingzhen; Huang, Wenxiu; Huang, Sijia; Xu, Zhiqiang; Chen, Jiang; Wu, Dong

    2015-04-01

    A firm peri-implant soft tissue seal is important for the long-term survival of dental implants, which demands the properties of antibacterial and cytocompatibility of the implant surfaces. In this study, GL13K, a cationic antimicrobial peptide, was immobilized onto microgroove surfaces which were 60 μm in width and 10 μm in depth, and the modified surfaces improved both the properties of antibacterial and cytocompatibility. The method of silanization was used to immobilize the antimicrobial peptide GL13K, which was confirmed by X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), atomic force microscopy (AFM), water contact angle measurement. Then the mechanical stability of the coatings was confirmed by ultrasonication. In vitro antibacterial tests confirmed bactericidal activity against Porphyromonas gingivalis without inhibiting its adhesion. In vitro cytocompatibility tests also confirmed that adhesion at later phase and proliferation of HGFs were greater (P<0.01) on the GL13K-modified microgroove surfaces than on the non-treated microgroove surfaces, and both of them were greater than on the smooth surfaces. The phenomenon of the contact guidance, which is cell growth aligned along the microgrooves, was maintained. Overall, this study developed a promising bi-functional surface that combined the physical and chemical properties to promote cytocompatibility and antibacterial activity simultaneously.

  13. Functionalized Stress Component onto Bio-template as a Pathway of Cytocompatibility

    Science.gov (United States)

    Keshavarz, Meysam; Tan, Bo; Venkatakrishnan, Krishnan

    2016-10-01

    This in-vitro study introduces residual stress as a third dimension of cell stimulus to modulate the interaction between cells and bio-template, without the addition of either chemical or physical stimuli onto the bio-template surface. Ultrashort Pulsed Laser (USPL) irradiation of silicon-based bio-template causes recrystallization of silicon, which mismatches the original crystal orientation of the virgin silicon. Consequently, subsurface Induced Residual Stress (IRS) is generated. The IRS components demonstrated a strong cytocompatibility, whereas the peripheral of IRS, which is the interface between the IRS component and the virgin silicon surface, a significant directional cell alignment was observed. Fibroblast cells shown to be more sensitive to the stress component than Hela cancer cells. It revealed that cytocompatibility in terms of cell migration and directional cell alignment is directly proportional to the level of the IRS component. Higher stress level results in more cell alignment and border migration width. There is a stress threshold below which the stress component completely loses the functionality. These results pointed to a functionalized bio-template with tunable cytocompatibility. This study may lead to a new tool for the designing and engineering of bio-template.

  14. Antimicrobial Properties and Cytocompatibility of PLGA/Ag Nanocomposites

    Directory of Open Access Journals (Sweden)

    Mariangela Scavone

    2016-01-01

    Full Text Available The purpose of this study was to investigate the antimicrobial properties of multifunctional nanocomposites based on poly(dl-Lactide-co-Glycolide (PLGA and increasing concentration of silver (Ag nanoparticles and their effects on cell viability for biomedical applications. PLGA nanocomposite films, produced by solvent casting with 1 wt%, 3 wt% and 7 wt% of Ag nanoparticles were investigated and surface properties were characterized by atomic force microscopy and contact angle measurements. Antibacterial tests were performed using an Escherichia coli RB and Staphylococcus aureus 8325-4 strains. The cell viability and morphology were performed with a murine fibroblast cell line (L929 and a human osteosarcoma cell line (SAOS-2 by cell viability assay and electron microscopy observations. Matrix protein secretion and deposition were also quantified by enzyme-linked immunosorbent assay (ELISA. The results suggest that the PLGA film morphology can be modified introducing a small percentage of silver nanoparticles, which induce the onset of porous round-like microstructures and also affect the wettability. The PLGA/Ag films having silver nanoparticles of more than 3 wt% showed antibacterial effects against E. coli and S. aureus. Furthermore, silver-containing PLGA films displayed also a good cytocompatibility when assayed with L929 and SAOS-2 cells; indicating the PLGA/3Ag nanocomposite film as a promising candidate for tissue engineering applications.

  15. In vitro bioactivity and cytocompatibility of tricalcium silicate

    Indian Academy of Sciences (India)

    Xiaoming Liao; Hongyang Zhu; Guangfu Yin; Zhongbing Huang; Yadong Yao; Xianchun Chen

    2011-08-01

    The in vitro bioactivity of tricalcium silicate (Ca3SiO5) ceramics was investigated by the bone-like apatite-formation ability in simulated body fluid (SBF), and the cytocompatibility was evaluated through osteoblast adhesion and proliferation assay. The results show that the Ca3SiO5 ceramics possess bone-like apatite formation ability in SBF. In vitro cytocompatible evaluation reveals that osteoblasts adhere and spread well on the Ca3SiO5 ceramics, indicating good bioactivity and cytocompatibility.

  16. Structure, physical properties, hemocompatibility and cytocompatibility of starch/zein composites.

    Science.gov (United States)

    Liu, Xing; Xie, Yi; Li, Wei; Sheng, Wen; Li, Yinping; Tong, Zan; Ni, Hong; Huselstein, Celine; Wang, Xiong; Chen, Yun

    2015-01-01

    A series of composite films were prepared from glycerol-plasticized starch and zein by intensive mixing and hot press. The structure and physical properties of the starch/zein (SZ) composite films were characterized by scanning electron microscope (SEM), optical microscopy and water contract angle testing. The hemocompatibility and cytocompatibility of SZ films were evaluated by plasma recalcification time, hemolysis assay and cell culture experiment. SEM and optical observation showed that starch and zein domains can be differed in the films and in a two phase separation status. Glycerol affects the surface hydrophilicity/hydrophobicity of the films. The hemocompatibility and cytocompatibility evaluation showed that SZ composites are anticoagulant materials with no hemolysis and low cytotoxicity. The SZ composites maybe have potentials for applications as biomaterials.

  17. Internal distribution of micro- / nano-sized inorganic particles and their cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Abe, Shigeaki; Iwadera, Nobuki; Esaki, Mitsue; Kida, Ikuhiro; Akasaka, Tsukasa; Uo, Motohiro; Yawaka, Yasutaka; Watari, Fumio [Graduate School of Dental Medicine, Hokkaido University, Sapporo 060-8586 (Japan); Mutoh, Mami [School of Dental Medicine, Hokkaido University, Sapporo 060-8586 (Japan); Morita, Manabu [Department of Oral Health, Okayama University Graduate School of Medicine, Dentisity and Pharmaceutical Science, Okayama 700-8525 (Japan); Haneda, Koichi [Department of Information Technology and Electronics, Senshu University of Ishinomaki, Ishinomaki 986-8580 (Japan); Yonezawa, Tetsu, E-mail: sabe@den.hokudai.ac.jp [Graduate School of Engineering, Hokkaido University, Sapporo 060-8628 (Japan)

    2011-10-29

    Nano-sized materials have received much attention lately, both in terms of their multiple applications and their biocompatibility. From both viewpoints, understanding the biodistribution of administered nano-materials is very important. In this study, we succeeded in visualizing the biodistribution of administered nano-materials using a scanning X-ray analytical microscope and magnetic resonance imaging method. Quantitative observation was carried out by inductively coupled plasma - atomic emission spectroscopy. We observed that the administered nano-particles accumulated in the liver, lung and spleen of mice. To estimate their cytocompatibility, the nano-particles were exposed to human liver cells. The results suggested that the micro-/ nano- particles have good cytocompatibility, except for copper oxide nano-particles.

  18. Cytocompatible and water stable ultrafine protein fibers for tissue engineering

    Science.gov (United States)

    Jiang, Qiuran

    This dissertation proposal focuses on the development of cytocompatible and water stable protein ultrafine fibers for tissue engineering. The protein-based ultrafine fibers have the potential to be used for biomedicine, due to their biocompatibility, biodegradability, similarity to natural extracellular matrix (ECM) in physical structure and chemical composition, and superior adsorption properties due to their high surface to volume ratio. However, the current technologies to produce the protein-based ultrafine fibers for biomedical applications still have several problems. For instance, the current electrospinning and phase separation technologies generate scaffolds composed of densely compacted ultrafine fibers, and cells can spread just on the surface of the fiber bulk, and hardly penetrate into the inner sections of scaffolds. Thus, these scaffolds can merely emulate the ECM as a two dimensional basement membrane, but are difficult to mimic the three dimensional ECM stroma. Moreover, the protein-based ultrafine fibers do not possess sufficient water stability and strength for biomedical applications, and need modifications such as crosslinking. However, current crosslinking methods are either high in toxicity or low in crosslinking efficiency. To solve the problems mentioned above, zein, collagen, and gelatin were selected as the raw materials to represent plant proteins, animal proteins, and denatured proteins in this dissertation. A benign solvent system was developed specifically for the fabrication of collagen ultrafine fibers. In addition, the gelatin scaffolds with a loose fibrous structure, high cell-accessibility and cell viability were produced by a novel ultralow concentration phase separation method aiming to simulate the structure of three dimensional (3D) ECM stroma. Non-toxic crosslinking methods using citric acid as the crosslinker were also developed for electrospun or phase separated scaffolds from these three proteins, and proved to be

  19. Influence of quaternization of ammonium on antibacterial activity and cytocompatibility of thin copolymer layers on titanium.

    Science.gov (United States)

    Waßmann, Marco; Winkel, Andreas; Haak, Katharina; Dempwolf, Wibke; Stiesch, Meike; Menzel, Henning

    2016-10-01

    Antimicrobial coatings are able to improve the osseointegration of dental implants. Copolymers are promising materials for such applications due to their combined properties of two different monomers. To investigate the influence of different monomer mixtures, we have been synthesized copolymers of dimethyl (methacryloxyethyl) phosphonate (DMMEP) and dipicolyl aminoethyl methacrylate in different compositions and have them characterized to obtain the r-parameters. Some of the copolymers with different compositions have also been alkylated with 1-bromohexane, resulting in quaternized ammonium groups. The copolymers have been deposited onto titanium surfaces resulting in ultrathin, covalently bound layers. These layers have been characterized by water contact angle measurements and ellipsometry. The influence of quaternary ammonium groups on antibacterial properties and cytocompatibility was studied: Activity against bacteria was tested with a gram positive Staphylococcus aureus strain. Cytocompatibility was tested with a modified LDH assay after 24 and 72 h to investigate adhesion and proliferation of human fibroblast cells on modified surfaces. The copolymer with the highest content of DMMEP showed a good reduction of S. aureus and in the alkylated version a very good reduction of about 95%. On the other hand, poor cytocompatibility is observed. However, our results show that this trend cannot be generalized for this copolymer system.

  20. Amidated pectin based hydrogels: synthesis, characterization and cytocompatibility study.

    Science.gov (United States)

    Mishra, R K; Singhal, J P; Datt, M; Banthia, A K

    2007-01-01

    The design and development of pectin-based hydrogels were attempted through the chemical modification of pectin with diethanolamine (DA). Diethanolamine modified pectin (DAMP) was synthesized by the chemical modification of pectin with varying concentrations of DA (1:1,1:2,1:3 and 1:4) at 5 oC in methanol. The modified product was used for the preparation of the hydrogel with glutaraldehyde (GA) reagent. The prepared hydrogels were characterized by Fourier transform infrared (FTIR) spectroscopy; organic elemental analysis, and X-ray diffraction (XRD), and swelling, hemocompatibility and cytocompatibility studies of the prepared hydrogels were also done. FTIR spectroscopy indicated the presence of primary and secondary amide absorption bands. The XRD pattern of the DAMP hydrogel clearly indicated that there was a considerable increase in crystallinity as compared to parent pectin. The degree of amidation (DA) and molar and mass reaction yields (Ym and Yn) was calculated based on the results of organic elemental analysis. Drug release studies from the hydrogel membranes were also evaluated in a Franz's diffusion cell. The hydrogels demonstrated good water holding properties and were found to be compatible with B-16 melanoma cells and human blood.

  1. Cytocompatibility of amine functionalized carbon nanoparticles grafted on polyethylene.

    Science.gov (United States)

    Žáková, Pavlína; Slepičková Kasálková, Nikola; Kolská, Zdeňka; Leitner, Jindřich; Karpíšková, Jana; Stibor, Ivan; Slepička, Petr; Švorčík, Václav

    2016-03-01

    Five types of amide-amine Carbon Nano-Particles (CNPs) were prepared by functionalization of CNPs and characterized by several analytical methods. The successful grafting of amines on CNPs was verified by X-ray photoelectron spectroscopy (XPS), organic elemental analysis and electrokinetic analysis. The size and morphology of CNPs were determined from transmission electron microscopy. The surface area and porosity of CNPs were examined by adsorption and desorption isotherms. Differential scanning calorimetry was used to investigate thermal stability of CNPs. The amount of bonded amine depends on its dimensionality arrangement. Surface area and pore volumes of CNPs decrease several times after individual amino-compound grafting. Selected types of functionalized CNPs were grafted onto a plasma activated surface of HDPE. The successful grafting of CNPs on the polymer surface was verified by XPS. Wettability was determined by contact angle measurements. Surface morphology and roughness were studied by atomic force microscopy. A dramatic decrease of contact angle and surface morphology was observed on CNP grafted polymer surface. Cytocompatibility of modified surfaces was studied in vitro, by determination of adhesion, proliferation and viability of vascular smooth muscle cells (VSMCs). Grafting of CNPs onto the polymer surface has a positive effect on the adhesion, proliferation and viability of VSMCs.

  2. Cytocompatibility between novel nerve conduit composite materials and bone marrow mesenchymal stem cells%新型神经导管复合材料与骨髓间充质干细胞的相容性*★

    Institute of Scientific and Technical Information of China (English)

    胡辉; 张伟才; 黄继锋; 严琼娇; 殷义霞; 李世普

    2013-01-01

      结果与结论:MTT检测结果显示,共培养5,7 d,实验组吸光度值高于对照组(P OBJECTIVE:To evaluate the cytocompatibility of rat bone marrow mesenchymal stem cel s with (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composites. METHODS:Passage 3 bone marrow mesenchymal stem cel s which were isolated from Sprague-Dawley rats were co-cultured with (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composite materials or their extracts, serving as experimental control. Another bone marrow mesenchymal stem cel s cultured in the culture medium containing 10%fetal bovine serum served as controls. Cel growth, survival and apoptosis on the composite materials were observed. RESULTS AND CONCLUSION:Results from 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay showed that absorbance values in the experimental group were higher than those in the control group after co-culture for days 5 and 7 (P<0.05). Annexin V-FITC/PI double staining results showed that the apoptosis rate of the experimental group was significantly lower than that of the control group (P<0.05). Under a scanning electron microscope, bone marrow mesenchymal stem cel s grew wel on the surface of (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composite materials. Many protrusions ran out from the cel s, and they were woven into a mesh, which was typical performance of neuron-like cel s. These findings indicate that (glycolic acid-L-lysine-lactic acid)/poly lactic acid/β-tricalcium phosphate/nerve growth factor composite materials have good cytocompatibility with bone marrow mesenchymal stem cel s, which can be regarded as an excel ent carrier for artificial nerve construction.

  3. Sequence-selective DNA recognition and enhanced cellular up-take by peptide-steroid conjugates.

    Science.gov (United States)

    Ruiz García, Yara; Iyer, Abhishek; Van Lysebetten, Dorien; Pabon, Y Vladimir; Louage, Benoit; Honcharenko, Malgorzata; De Geest, Bruno G; Smith, C I Edvard; Strömberg, Roger; Madder, Annemieke

    2015-12-25

    Several GCN4 bZIP TF models have previously been designed and synthesized. However, the synthetic routes towards these constructs are typically tedious and difficult. We here describe the substitution of the Leucine zipper domain of the protein by a deoxycholic acid derivative appending the two GCN4 binding region peptides through an optimized double azide-alkyne cycloaddition click reaction. In addition to achieving sequence specific dsDNA binding, we have investigated the potential of these compounds to enter cells. Confocal microscopy and flow cytometry show the beneficial influence of the steroid on cell uptake. This unique synthetic model of the bZIP TF thus combines sequence specific dsDNA binding properties with enhanced cell-uptake. Given the unique properties of deoxycholic acid and the convergent nature of the synthesis, we believe this work represents a key achievement in the field of TF mimicry.

  4. Enzymatic degradation behavior and cytocompatibility of silk fibroin-starch-chitosan conjugate membranes

    Energy Technology Data Exchange (ETDEWEB)

    Baran, Erkan T., E-mail: erkantur@metu.edu.tr; Tuzlakoglu, Kadriye, E-mail: kadriye@dep.uminho.pt; Mano, Joao F., E-mail: jmano@dep.uminho.pt; Reis, Rui L., E-mail: rgreis@dep.uminho.pt

    2012-08-01

    The objective of this study was to investigate the influence of silk fibroin and oxidized starch conjugation on the enzymatic degradation behavior and the cytocompatability of chitosan based biomaterials. The tensile stress of conjugate membranes, which was at 50 Megapascal (MPa) for the lowest fibroin and starch composition (10 weight percent (wt.%)), was decreased significantly with the increased content of fibroin and starch. The weight loss of conjugates in {alpha}-amylase was more notable when the starch concentration was the highest at 30 wt.%. The conjugates were resistant to the degradation by protease and lysozyme except for the conjugates with the lowest starch concentration. After 10 days of cell culture, the proliferation of osteoblast-like cells (SaOS-2) was stimulated significantly by higher fibroin compositions and the DNA synthesis on the conjugate with the highest fibroin (30 wt.%) was about two times more compared to the native chitosan. The light microscopy and the image analysis results showed that the cell area and the lengths were decreased significantly with higher fibroin/chitosan ratio. The study proved that the conjugation of fibroin and starch with the chitosan based biomaterials by the use of non-toxic reductive alkylation crosslinking significantly improved the cytocompatibility and modulated the biodegradation, respectively. - Highlights: Black-Right-Pointing-Pointer Silk fibroin, starch and chitosan conjugates were prepared by reductive alkylation. Black-Right-Pointing-Pointer The enzymatic biodegradation and the cytocompatibility of conjugates were tested. Black-Right-Pointing-Pointer The conjugate with 30% starch composition was degraded by {alpha}-amylase significantly. Black-Right-Pointing-Pointer Higher starch composition in conjugates prevented protease and lysozyme degradation. Black-Right-Pointing-Pointer Fibroin incorporation effectively increased the cell proliferation of conjugates.

  5. Cytocompatibility of Siloxane-Containing Vaterite/Poly(l-lactic acid Composite Coatings on Metallic Magnesium

    Directory of Open Access Journals (Sweden)

    Shinya Yamada

    2013-12-01

    Full Text Available Poly(l-lactic acid-based films which include 60 wt % of vaterite (V or siloxane-containing vaterite (SiV were coated on a pure magnesium substrate, denoted by PLLA/V or PLLA/SiV, respectively, to suppress early corrosion and improve its cytocompatibility. Both coating films adhered to the Mg substrate with 2.3–2.8 MPa of tensile bonding strength. Soaking test for 7 days in α-modified minimum essential medium revealed that the morphological instability of the PLLA/V film caused a higher amount of Mg2+ ion to be released from the coating sample. On the other hand, in the case of the coating with the PLLA/SiV film, no morphological change even after the soaking test was observed, owing to the suppression of the degradation rate. In cell culture tests, the proliferation of mouse osteoblast-like cell (MC3T3-E1 was significantly enhanced by both coatings, in comparison with the uncoated magnesium substrate. The cell morphology revealed that a few less-spread cells were observed on the PLLA/V film, while more elongated cells were done on the PLLA/SiV film. The cells on the PLLA/SiV film exhibited an extremely higher alkaline phosphatase activity after 21 days of incubation than that on the PLLA/V one. The PLLA/SiV film suppressed the early corrosion and enhanced cytocompatibility on metallic magnesium.

  6. Synthesis and neuro-cytocompatibility of magnetic Zn-ferrite nanorods via peptide-assisted process.

    Science.gov (United States)

    Zou, Yuanwen; Huang, Zhongbing; Deng, Min; Yin, Guangfu; Chen, Xianchun; Liu, Juan; Wang, Yan; Yan, Li; Gu, Jianwen

    2013-10-15

    In order to obtain magnetic nanorods (MNRs) with the neuro-cytocompatibility, silk-fibroin (SF)-coated Zn-ferrite NRs are successfully prepared via a mineralization process, and their saturation magnetization is 32emu g(-)(1). After the mineralization of 2d and 4d in the mixed solution of the concentrations of 15w/w% SF and 0.01M HCl, the lengths of NRs are ∼220nm and ∼2μm, respectively. Cell tests of NRs with 220nm length showed that the as-prepared Zn-ferrite NRs hardly produced toxicity on Escherichiacoli, Staphylococcusaureus, L929, and PC12 cells. The results of the outgrown neurites from PC12 cells indicated that the neurite length and the number of neurites were not significantly decreased at the low concentrations of SF-coated NRs (less than 0.25mg mL(-)(1)) in 1-5d culture time. TEM images of cell ultrathin sections indicated that, although Zn-ferrite NRs were split in the cytosol for 5d at the NR concentrations of 0.125mg mL(-)(1), some integrated mitochondria in a neurite suggested that SF-coated NRs inside cells did not influence the extension activity of neurites. Based on the good neuro-cytocompatibility and magnetic property of Zn-ferrite NRs, their potential applications in safe cell manipulation and axon guidance can be envisioned.

  7. Development of highly luminescent and cytocompatible near-IR-emitting aqueous Ag2S quantum dots

    OpenAIRE

    Hocaoğlu, İbrahim; Sennaroğlu, Alphan ; Acar, Funda Havva Yağcı; Çizmeciyan, M. Natali; Erdem, Rengin ; Özen, Can ; Kurt, Adnan

    2012-01-01

    Colloidally stable and highly luminescent near-IR emitting Ag2S quantum dots (NIRQDs) were prepared by a very simple aqueous method using 2-mercaptopropionic acid (2MPA) as a coating. Emission of Ag2S-2MPA NIRQDs can be tuned between 780 and 950 nm. These NIRQDs have photoluminescence quantum yields (PLQY) around 7–39% and exhibit excellent cytocompatibility even at 600 mg mL 1 in NIH/3T3 cells. With such improved properties, Ag2S-2MPA NIRQDs have a great potential in practical...

  8. Cytocompatibility assessment of chemical surface treatments for phosphate glass to improve adhesion between glass and polyester.

    Science.gov (United States)

    S Hasan, M; Ahmed, I; Parsons, A J; Walker, G S; Scotchford, C A

    2013-11-01

    Fully resorbable phosphate glass fiber reinforced polymer composites have shown real potential for replacing some of the existing metallic bone fracture fixation devices. However, some of these composites have not provided suitable mechanical strength profiles over the required healing period for bone. Typically, it has been seen that these composites can lose up to 50% or more of their strength within the first week of degradation. Functionalizing the glass surface to promote polymer adhesion or to introduce hydrophobicity at the glass surface could potentially introduce control over the mechanical properties of the composite and their retention. In this study eight chemical agents namely, Glycerol 2-phosphate disodium salt; 3-phosphonopropionic acid; 3-aminopropyltriethoxy silane; etidronic acid; hexamethylene diisocyanate; sorbitol/sodium ended PLA oligomers and amino phosphonic acid, were selected to functionalise the bulk phosphate glass surface. Selected chemical agents had one functional group (-OH or O C N) to react with the glass and another functionality (either -OH, NH2, or Na) to react with the polymer matrix and/or produce hydrophobicity at the fiber surface. Bulk phosphate glass surface-treated with the above agents were assessed for the cytotoxicity of degradation products cell-material interaction in short- and long-term direct cytocompatibility studies. Results obtained from these cytocompatibility studies (using human osteosarcoma (MG63) and primary human osteoblast cell lines) revealed no cytotoxicity from the degradation products and a response comparable to controls in terms of cell functions (attachment, viability, metabolic activity, proliferation, and differentiation) and morphology.

  9. Conformal cytocompatible ferrite coatings facilitate the realization of a nanovoyager in human blood.

    Science.gov (United States)

    Venugopalan, Pooyath Lekshmy; Sai, Ranajit; Chandorkar, Yashoda; Basu, Bikramjit; Shivashankar, Srinivasrao; Ghosh, Ambarish

    2014-01-01

    Controlled motion of artificial nanomotors in biological environments, such as blood, can lead to fascinating biomedical applications, ranging from targeted drug delivery to microsurgery and many more. In spite of the various strategies used in fabricating and actuating nanomotors, practical issues related to fuel requirement, corrosion, and liquid viscosity have limited the motion of nanomotors to model systems such as water, serum, or biofluids diluted with toxic chemical fuels, such as hydrogen peroxide. As we demonstrate here, integrating conformal ferrite coatings with magnetic nanohelices offer a promising combination of functionalities for having controlled motion in practical biological fluids, such as chemical stability, cytocompatibility, and the generated thrust. These coatings were found to be stable in various biofluids, including human blood, even after overnight incubation, and did not have significant influence on the propulsion efficiency of the magnetically driven nanohelices, thereby facilitating the first successful "voyage" of artificial nanomotors in human blood. The motion of the "nanovoyager" was found to show interesting stick-slip dynamics, an effect originating in the colloidal jamming of blood cells in the plasma. The system of magnetic "nanovoyagers" was found to be cytocompatible with C2C12 mouse myoblast cells, as confirmed using MTT assay and fluorescence microscopy observations of cell morphology. Taken together, the results presented in this work establish the suitability of the "nanovoyager" with conformal ferrite coatings toward biomedical applications.

  10. Enhanced cytocompatibility of silver-containing biointerface by constructing nitrogen functionalities

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Wei, E-mail: weizhang@mail.ipc.ac.cn [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Liu, Jun [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Wang, Huaiyu [Department of Physics & Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China); Xu, Ying; Wang, Pingli [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Ji, Junhui, E-mail: jhji@mail.ipc.ac.cn [Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190 (China); Chu, Paul K. [Department of Physics & Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

    2015-09-15

    Graphical abstract: Constructing nitrogen functionalities is promising method to enhance cytocompatibility of the biointerface by simultaneous Ag and N{sub 2} plasma modification. - Highlights: • N{sub 2} plasma immersion ion implantation (PIII) treatment generates plenty of nitrogen functionalities on polymer substrate. • N{sub 2} PIII treatment increases surface roughness and hydrophilicity and improves its capability to adsorb protein. • Simultaneous Ag and N{sub 2} plasma modification constructs nitrogen functionalities to enhance cytocompatibility of the biointerface. - Abstract: Silver (Ag) has recently been introduced into polymeric biomedical implants by plasma immersion ion implantation (PIII) to enhance the antibacterial capability. However, Ag ions and nanoparticles can increase the cytotoxicity and inhibit cellular proliferation and the relationship is time- and dose-dependent. In this study, Ag and N{sub 2} PIII is conducted in concert to produce nitrogen functional groups as well as Ag-containing biointerface. In addition to the creation of nitrogen functionalities, the surface roughness and hydrophilicity are improved in favor of protein adsorption. Compared to the biointerface created by Ag PIII only, the nitrogen functionalities generated by N{sub 2} co-PIII do not affect DNA synthesis and the total protein level but evidently enhance cellular adhesion, viability, and proliferation at the biointerface. The modified surface is observed to upregulate the osteogenesis-related marker expression of bone cells in contact. Our findings suggest that dual Ag and N{sub 2} PIII is a desirable technique to enhance both the cytocompatibility and antibacterial capability of medical polymers.

  11. Cytocompatibility of biodegradable poly(ethylene glycol)-b-poly(L-lactide)-b-poly(L-glutamic acid) tri-block copolymer with human umbilical vein endothelial cells%生物可降解材料聚乙二醇-聚乳酸-聚谷氨酸三嵌段共聚物与人脐静脉内皮细胞的相容性

    Institute of Scientific and Technical Information of China (English)

    刘斌; 宋显晶; 刘婕妤; 姜锋; 史永峰; 双东思; 李智博

    2008-01-01

    BACKGROUND: Poly(ethylene glycol)-b-poly(L-lactide)-b-poly(L-glutamic acid) (PEG-PLA-PGL) tri-block copolymers have good applied foreground in constructing tissue engineering scaffold materials. Whether endothelial cells survive and grow on the materials has a direct influence on the application as a biodegradable material for the scaffold of endothelial cell vector.OBJECTIVE: To explore the cytocompatibility of PEG-PLA-PGL tri-block copolymers with human umbilical vein endothelial cells (HUVECs).DESIGN: Randomized control observation.SETTING: the Second Hospital of Jilin University.MATERIALS: The experiment was carried out in the Department of Pathobiology, School of Basic Medical Sciences, Jilin University from February to October in 2006. Human umbilical cord about 20 cm length came from one neonatal infant who was delivered normally after enough months in the Department of Gynecology and Obstetrics, the Second Hospital of Jilin University. Human umbilical cord was sampled in the informed consents of the infant's family member. The experimentation was authorized by the medical ethic committee of the hospital. PEG-PLA-PGL membranes were provided by Changchun Institute of Applied Chemistry, Chinese Academy of Sciences. Inverted microscope and phase-contrast microscope were bought from Olympus Company (Japan).METHODS: HUVECs cultivated and grew steadily, were inoculated onto PEG-PLA-PGL membranes, serving as the experiment group. While the culture medium without PEG-PLA-PGL membranes were taken as the control group.①Cytocompatibility of PEG-PLA-PGL membranes with HUVECs was evaluated by observing cellular growth through phase-contrast microscope.②The proliferation index of cells was detected by MTT method in 1, 3, 5 and 7 days after inoculation.MAIN OUTCOME MEASURES: ①Cytocompatibility of PEG-PLA-PGL membranes with HUVECs;②The proliferation index of cells in l, 3, 5 and 7 days after inoculationRESULTS: ①Cytocompatibility of PEG-PLA-PGL membranes with

  12. Boron nitride nanotubes coated with organic hydrophilic agents: Stability and cytocompatibility studies

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Tiago Hilário; Soares, Daniel Crístian Ferreira; Moreira, Luciana Mara Costa; Ornelas da Silva, Paulo Roberto [Serviço de Nanotecnologia, Centro de Desenvolvimento da Tecnologia Nuclear CDTN/CNEN, Avenida Presidente Antônio Carlos, 6.627, Campus da UFMG, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais (Brazil); Gouvêa dos Santos, Raquel [Laboratório de Radiobiologia, Centro de Desenvolvimento da Tecnologia Nuclear CNEN/CDTN, Av. Presidente Antônio Carlos 6.627, Campus da UFMG, Pampulha, 31270-901 Belo Horizonte, Minas Gerais (Brazil); Barros de Sousa, Edésia Martins, E-mail: sousaem@cdtn.br [Serviço de Nanotecnologia, Centro de Desenvolvimento da Tecnologia Nuclear CDTN/CNEN, Avenida Presidente Antônio Carlos, 6.627, Campus da UFMG, Pampulha, CEP 31270-901 Belo Horizonte, Minas Gerais (Brazil)

    2013-12-01

    In the present study, Boron Nitride Nanotubes (BNNTs) were synthesized and functionalized with organic hydrophilic agents constituted by glucosamine (GA), polyethylene glycol (PEG){sub 1000}, and chitosan (CH) forming new singular systems. Their size, distribution, and homogeneity were determined by photon correlation spectroscopy, while their surface charge was determined by laser Doppler anemometry. The morphology and structural organization were evaluated by Transmission Electron Microscopy. The functionalization was evaluated by Thermogravimetry analysis and Fourier Transformer Infrared Spectroscopy. The results showed that BNNTs were successfully obtained and functionalized, reaching a mean size and dispersity deemed adequate for in vitro studies. The in vitro stability tests also revealed a good adhesion of functionalized agents on BNNT surfaces. Finally, the in vitro cytocompatibility of functionalized BNNTs against MCR-5 cells was evaluated, and the results revealed that none of the different functionalization agents disturbed the propagation of normal cells up to the concentration of 50 μg/mL. Furthermore, in this concentration, no significantly chromosomal or morphologic alterations or increase in ROS (Reactive Oxygen Species) could be observed. Thus, findings from the present study reveal an important stability and cytocompatibility of functionalized BNNTs as new potential drugs or radioisotope nanocarriers to be applied in therapeutic procedures. - Highlights: • BNNTs were synthesized and functionalized with organic hydrophilic agents. • Hydrophilic molecules do not alter the biocompatibility profile of BNNTs. • No significantly chromosomal or morphologic alterations in ROS could be observed.

  13. Properties and osteoblast cytocompatibility of self-curing acrylic cements modified by glass fillers.

    Science.gov (United States)

    Lopes, P; Garcia, M P; Fernandes, M H; Fernandes, M H V

    2013-11-01

    Materials filled with a silicate glass (MSi) and a borate glass (MB) were developed and compared in terms of their in vitro behavior. The effect of filler composition and concentration (0, 30, 40 and 50 wt%) on the curing parameters, residual monomer, water uptake, weight loss, bioactivity, mechanical properties (bending and compression) and osteoblast cytocompatibility was evaluated. The addition of bioactive glass filler significantly improved the cements curing parameters and the mechanical properties. The most relevant results were obtained for the lower filler concentration (30 t%) a maximum flexural strength of 40.4 Pa for MB3 and a maximum compressive strength of 95.7 MPa for MSi3. In vitro bioactivity in acellular media was enhanced by the higher glass contents in the cements. Regarding the biological assessment, the incorporation of the silicate glass significantly improved osteoblast cytocompatibility, whereas the presence of the borate glass resulted in a poor cell response. Nevertheless it was shown that the surviving cells on the MB surface were in a more differentiated stage compared to those growing over non-filled poly(methyl methacrylate). Results suggest that the developed formulations offer a high range of properties that might be interesting for their use as self-curing cements.

  14. Bioactivity and cytocompatibility of zirconia (ZrO(2)) films fabricated by cathodic arc deposition.

    Science.gov (United States)

    Liu, Xuanyong; Huang, Anping; Ding, Chuanxian; Chu, Paul K

    2006-07-01

    Zirconium oxide thin films were fabricated on silicon wafers using a filtered cathodic arc system in concert with oxygen plasma. The structure and phase composition of the zirconium oxide thin films were characterized by atomic force microscopy (AFM), X-ray diffraction (XRD), Rutherford backscattering spectrometry (RBS), and transmission electron microscopy (TEM). The bioactivity was assessed by investigating the formation of apatite on the film surface after soaking in simulated body fluids. Bone marrow mesenchymal stem cells (BMMSC) were used to further evaluate the cytocompatibility of the materials. The results indicate that the films are composed of stoichiometric ZrO(2) and the composition is quite uniform throughout the thickness. Bone-like apatite can be formed on the surface of the ZrO(2) thin film in our SBF immersion experiments, suggesting that the surface is bioactive. The outermost layer of the ZrO(2) thin film comprises nano-sized particles that can be identified by AFM images taken on the thin film surface and TEM micrographs obtained from the interface between the ZrO(2) thin film and apatite layer. The nanostructured surface is believed to be the key factor that apatite is induced to precipitate on the surface. Bone marrow mesenchymal stem cells are observed to grow and proliferate in good states on the film surface. Our results show that ZrO(2) thin films fabricated by cathodic arc deposition exhibit favorable bioactivity and cytocompatibility.

  15. Guanidine hydrochloride embedded polyurethanes as antimicrobial and absorptive wound dressing membranes with promising cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Sahraro, Maryam; Yeganeh, Hamid, E-mail: h.yeganeh@ippi.ac.ir; Sorayya, Marziyeh

    2016-02-01

    Preparation and assessments of novel absorptive wound dressing materials with efficient antimicrobial activity as well as very good cytocompatibility were described in this work. An amine terminated poly(hexamethylene guanidine hydrochloride) was prepared and used as curing agent of different epoxy-terminated polyurethane prepolymers. The structures of prepared materials were elucidated by evaluation of their {sup 1}H NMR and FTIR spectra. The recorded tensile strength of membranes confirmed the excellent dimensional stability of the film type dressings even at fully hydrated conditions. Therefore, these dressings could protect the wound bed from external forces during the healing period. The structurally optimized dressing membranes could preserve the desired moist environment over the wounded area, as a result of their balanced equilibrium, water absorption and water vapor transmission rate. Therefore, a very good condition for stimulation of self-healing of wound bed was attained. Also, owing to the presence of guanidine hydrochloride moieties embedded into the structure of dressings, efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans were detected. In vitro cytotoxicity assay of the prepared dressings revealed cytocompatibility of these materials against fibroblast cells. Therefore, they could support cell growth and proliferation at the wounded area. - Highlights: • New polyurethane wound dressings with guanidine hydrochloride based antimicrobials • Maintaining moist and warm wound environment for accelerating healing • Proper tensile strength of dressings even at fully hydrated state • Excellent biocompatibility index due to proper selection of starting materials.

  16. Guanidine hydrochloride embedded polyurethanes as antimicrobial and absorptive wound dressing membranes with promising cytocompatibility.

    Science.gov (United States)

    Sahraro, Maryam; Yeganeh, Hamid; Sorayya, Marziyeh

    2016-02-01

    Preparation and assessments of novel absorptive wound dressing materials with efficient antimicrobial activity as well as very good cytocompatibility were described in this work. An amine terminated poly(hexamethylene guanidine hydrochloride) was prepared and used as curing agent of different epoxy-terminated polyurethane prepolymers. The structures of prepared materials were elucidated by evaluation of their (1)H NMR and FTIR spectra. The recorded tensile strength of membranes confirmed the excellent dimensional stability of the film type dressings even at fully hydrated conditions. Therefore, these dressings could protect the wound bed from external forces during the healing period. The structurally optimized dressing membranes could preserve the desired moist environment over the wounded area, as a result of their balanced equilibrium, water absorption and water vapor transmission rate. Therefore, a very good condition for stimulation of self-healing of wound bed was attained. Also, owing to the presence of guanidine hydrochloride moieties embedded into the structure of dressings, efficient antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans were detected. In vitro cytotoxicity assay of the prepared dressings revealed cytocompatibility of these materials against fibroblast cells. Therefore, they could support cell growth and proliferation at the wounded area.

  17. Regenerated collagen fibers with grooved surface texture: Physicochemical characterization and cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Xiang [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China); Wu, Tong [College of Chemistry, Chemical Engineering and Biotechnology, Donghua University, Shanghai 201620 (China); Wang, Wei [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China); Huang, Chen, E-mail: hc@dhu.edu.cn [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China); Jin, Xiangyu [Engineering Research Center of Technical Textiles, Ministry of Education, College of Textiles, Donghua University, Shanghai 201620 (China)

    2016-01-01

    A novel type of protein fibers, regenerated collagen fibers (RC) from cattle skin, was prepared through wet-spinning. Due to the combined effect of solvent exchange and subsequent drawing process, the fibers were found to have a grooved surface texture. The grooves provided not only ordered topographical cues, but also increased surface area. Protein content of the RC fibers was confirmed by Fourier Transform infrared spectroscopy (FTIR) and ninhydrin color reaction. The fibers could be readily fabricated into nonwovens or other textiles, owning to their comparable physical properties to other commercialized fibers. Cell growth behavior on RC nonwovens suggested both early adhesion and prompt proliferation. The high moisture regain, good processability, along with the excellent cytocompatibility indicated that the RC fibers and nonwovens developed in this study might offer a good candidate for biomedical and healthcare applications. - Highlights: • Wet-spun regenerated collagen fibers having aligned surface grooves • Comparable physiochemical properties to commercialized fibers • Readily processed into nonwovens • Excellent cytocompatibility with prompt cell adhesion and proliferation.

  18. Cytocompatibility studies of vertically-aligned multi-walled carbon nanotubes: Raw material and functionalized by oxygen plasma

    Energy Technology Data Exchange (ETDEWEB)

    Lobo, A.O., E-mail: loboao@yahoo.com [Laboratorio Associado de Sensores e Materiais, INPE, Sao Jose dos Campos/SP (Brazil); Instituto Tecnologico de Aeronautica, ITA, Sao Jose dos Campos/SP (Brazil); Laboratorio de Nanotecnologia Biomedica, Universidade do Vale do Paraiba, Sao Jose dos Campos/SP (Brazil); Corat, M.A.F. [Centro Multidisciplinar para Investigacao Biologica na Area da Ciencia em Animais de Laboratorio, CEMIB, UNICAMP, Campinas/SP (Brazil); Antunes, E.F. [Laboratorio Associado de Sensores e Materiais, INPE, Sao Jose dos Campos/SP (Brazil); Instituto Tecnologico de Aeronautica, ITA, Sao Jose dos Campos/SP (Brazil); Ramos, S.C. [Instituto Tecnologico de Aeronautica, ITA, Sao Jose dos Campos/SP (Brazil); Pacheco-Soares, C. [Laboratorio de Dinamica de Compartimentos Celulares, UNIVAP, Sao Jose dos Campos/SP (Brazil); and others

    2012-05-01

    It was presented a strong difference on cell adhesion and proliferation of functionalized vertically-aligned multi-walled carbon nanotube (VACNT) scaffolds compared to raw-VACNT. Biocompatibility in vitro tests were performed on raw-VACNT after superficial modification by oxygen plasma, which changes its superhydrophobic character to superhydrophilic. Two cytocompatibility tests were applied: 1) total lactate dehydrogenase colorimetric assay for the study of proliferating cells; and 2) cellular adhesion by scanning electron microscopy. Results showed that superhydrophilic VACNT scaffolds stimulate cell growth with proliferation up to 70% higher than normal growth of cell culture.

  19. 物理联合化学或化学方法处理去抗原异种松质骨支架与骨髓间充质干细胞的细胞相容性%Cytocompatibility of bone marrow mesenchymal stem cells and antigen-extracted xenogeneic cancellous bone scaffold treated by physiochemical or chemical method

    Institute of Scientific and Technical Information of China (English)

    许慧芬; 何惠宇; 唐小雪

    2012-01-01

    背景:研究证明去抗原异种松质骨支架具有良好的理化性能和三维立体多孔结构,但应用于临床还需要考虑其安全性和生物相容性.目的:比较物理联合化学及化学方法处理去抗原异种松质骨支架与羊骨髓间充质干细胞的细胞相容性.方法:用梯度密度离心法分离培养羊骨髓间充质干细胞,四甲基偶氮唑盐比色法检测物理联合化学及化学方法处理去抗原异种松质骨支架材料对骨髓间充质干细胞增殖的影响.取第3代骨髓间充质干细胞,接种在两种支架上共同培养,倒置相差显微镜和扫描电镜观察细胞在两种支架材料上的形态、黏附、生长和增殖情况.结果与结论:物理联合化学组细胞毒性为0或1级,细胞能在材料上良好地黏附、增殖、生长,细胞活性未受到支架材料的影响.化学组细胞毒性为3级,细胞在材料上生长受到抑制,支架孔隙内无细胞黏附.提示经过物理联合化学处理的去抗原异种松质骨支架材料与羊骨髓间充质干细胞具有良好的生物相容性;单纯经过化学处理的支架材料生物相容性较差,不符合生物材料安全性标准.%BACKGROUND: Antigen-extracted xenogeneic cancellous bone has been shown to be characterized by well physicochemical performance and three-dimensional stereo porous structure, however, the biocompatibility and safely still need to be further studied in clinical application.OBJECTIVE: To study the cytocompatibility of bone marrow mesenchymal stem cells (BMSCs) and antigen-extracted xenogeneic cancellous bone scaffold treated by chemical or physicochemical method.METHODS: The gradient density centrifugation was used to separate and cultivate sheep BMSCs, the influence of antigen-extracted xenogeneic cancellous bone scaffold materials treated by chemical or physicochemical method on the proliferation of the BMSCs were measured by four thiazole salt colorimetric experiment (MTT method). The

  20. Cytocompatibility of Highly Dispersed Nano Hydroxyapatite Sol

    Institute of Scientific and Technical Information of China (English)

    MAOXuan; WUPei-zhu; TANGShun-qing; YANYan-ling; DAIYun

    2004-01-01

    Nano hydroxyapatite (HA) crystals were prepared and dispersed in water to form HA sol by simple methods. The cytotoxicity of the sols were tested by MTT assay and lymphocytotoxicity test. Results show that the average secondary particle size of the sol containing uncalcined HA crystals is around 750 nm, within micrograde; while the sol of calcined HA contains over 88% nanoparticles with the size between 65~86 nm, in which nano HA crystals are highly dispersed. Both the HA sols have no toxicity on the proliferation of 3T3 cells and lymphocytes. It demonstrates that the nano sol is safe for the application of drug delivery.

  1. Regenerated collagen fibers with grooved surface texture: Physicochemical characterization and cytocompatibility.

    Science.gov (United States)

    Wang, Xiang; Wu, Tong; Wang, Wei; Huang, Chen; Jin, Xiangyu

    2016-01-01

    A novel type of protein fibers, regenerated collagen fibers (RC) from cattle skin, was prepared through wet-spinning. Due to the combined effect of solvent exchange and subsequent drawing process, the fibers were found to have a grooved surface texture. The grooves provided not only ordered topographical cues, but also increased surface area. Protein content of the RC fibers was confirmed by Fourier Transform infrared spectroscopy (FTIR) and ninhydrin color reaction. The fibers could be readily fabricated into nonwovens or other textiles, owning to their comparable physical properties to other commercialized fibers. Cell growth behavior on RC nonwovens suggested both early adhesion and prompt proliferation. The high moisture regain, good processability, along with the excellent cytocompatibility indicated that the RC fibers and nonwovens developed in this study might offer a good candidate for biomedical and healthcare applications.

  2. Improving gelation efficiency and cytocompatibility of visible light polymerized thiol-norbornene hydrogels via addition of soluble tyrosine.

    Science.gov (United States)

    Shih, Han; Liu, Hung-Yi; Lin, Chien-Chi

    2017-02-28

    Hydrogels immobilized with biomimetic peptides have been used widely for tissue engineering and drug delivery applications. Photopolymerization has been among the most commonly used techniques to fabricate peptide-immobilized hydrogels as it offers rapid and robust peptide immobilization within a crosslinked hydrogel network. Both chain-growth and step-growth photopolymerizations can be used to immobilize peptides within covalently crosslinked hydrogels. A previously developed visible light mediated step-growth thiol-norbornene gelation scheme has demonstrated efficient crosslinking of hydrogels composed of an inert poly(ethylene glycol)-norbornene (PEGNB) macromer and a small molecular weight bis-thiol linker, such as dithiothreitol (DTT). Compared with conventional visible light mediated chain-polymerizations where multiple initiator components are required, step-growth photopolymerized thiol-norbornene hydrogels are more cytocompatible for the in situ encapsulation of radical sensitive cells (e.g., pancreatic β-cells). This contribution explored visible light based crosslinking of various bis-cysteine containing peptides with macromer 8-arm PEGNB to form biomimetic hydrogels suitable for in situ cell encapsulation. It was found that the addition of soluble tyrosine during polymerization not only significantly accelerated gelation, but also improved the crosslinking efficiency of PEG-peptide hydrogels as evidenced by a decreased gel point and enhanced gel modulus. In addition, soluble tyrosine drastically enhanced the cytocompatibility of the resulting PEG-peptide hydrogels, as demonstrated by in situ encapsulation and culture of pancreatic MIN6 β-cells. This visible light based thiol-norbornene crosslinking mechanism provides an attractive gelation method for preparing cytocompatible PEG-peptide hydrogels for tissue engineering applications.

  3. Cytocompatibility of Plasma and Thermally Treated Biopolymers

    Directory of Open Access Journals (Sweden)

    Petr Slepička

    2013-01-01

    Full Text Available This paper is focused on the surface characterization of plasma and consequently thermally treated biocompatible polymers. PLLA (poly(L-lactide acid and PMP (poly-4-methyl-1-pentene are studied. The influence of Ar plasma treatment on the surface polarity of substrate measured immediately after treatment and during the polymer surface aging is studied. Surface roughness, morphology, wettability, and surface chemistry were determined. Plasma treatment leads to significant changes in PLLA surface morphology and chemistry, with the PMP being slightly affected. The higher resistance to plasma fluence results in smaller ablation of PMP than that of PLLA. The plasma treatment improves cell adhesion and proliferation on the PMP. Plasma treatment of PLLA influences mostly the homogeneity of adhered and proliferated VSMC.

  4. Hydroxyapatite coatings with oriented nanoplate and nanorod arrays: Fabrication, morphology, cytocompatibility and osteogenic differentiation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Wei [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Tian, Bo [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Lei, Yong; Ke, Qin-Fei [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Zhu, Zhen-An, E-mail: zhuzhenan2006@126.com [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Guo, Ya-Ping, E-mail: ypguo@shnu.edu.cn [The Education Ministry Key Lab of Resource Chemistry and Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China)

    2016-10-01

    Hydroxyapatite (HA) crystals exhibit rod-like shape with c-axis orientation and plate-like shape with a(b)-axis orientation in vertebrate bones and tooth enamel surfaces, respectively. Herein, we report the synthesis of HA coatings with the oriented nanorod arrays (RHACs) and HA coatings with oriented nanoplate arrays (PHACs) by using bioglass coatings as sacrificial templates. After soaking in simulated body fluid (SBF) at 120 °C, the bioglass coatings are hydrothermally converted into the HA coatings via a dissolution-precipitation reaction. If the Ca/P ratios in SBF are 2.50 and 1.25, the HA crystals on the coatings are oriented nanorod arrays and oriented nanoplate arrays, respectively. Moreover, the bioglass coatings are treated with SBF at 37 °C, plate-like HA coatings with a low crystallinity (SHACs) are prepared. As compared with the Ti6Al4V and SHACs, the human bone marrow stromal cells (hBMSCs) on the RHACs and PHACs have better cell adhesion, spreading, proliferation and osteogenic differentiation because of their moderately hydrophilic surfaces and similar chemical composition, morphology and crystal orientation to human hard tissues. Notably, the morphologies of HA crystals have no obvious effects on cytocompatibility and osteogenic differentiation. Hence, the HA coatings with oriented nanoplate arrays or oriented nanorod arrays have a great potential for orthopedic applications. - Highlights: • We prepare hydroxyapatite coatings with oriented nanoplate and nanorod arrays. • Hydroxyapatite coatings are in situ converted from bioglass coatings. • Hydroxyapatite coatings have good cytocompatibility and osteogenic differentiation. • Oriented hydroxyapatite coatings are used for orthopedic implants.

  5. In vitro haematic proteins adsorption and cytocompatibility study on acrylic copolymer to realise coatings for drug-eluting stents

    Energy Technology Data Exchange (ETDEWEB)

    Gagliardi, Mariacristina, E-mail: mariacristina.gagliardi@iit.it

    2012-12-01

    In the present paper, a preliminary in vitro analysis of biocompatibility of newly-synthesised acrylic copolymers is reported. In particular, with the aim to obtain coatings for drug-eluting stents, blood protein absorption and cytocompatibility were studied. For protein absorption tests, bovine serum albumin and bovine plasma fibrinogen were considered. Cytocompatibility was tested using C2C12 cell line as model, analysing the behaviour of polymeric matrices and of drug-eluting systems, obtained loading polymeric matrices with paclitaxel, an anti-mitotic drug, in order to evaluate the efficacy of a pharmacological treatment locally administered from these materials. Results showed that the amount of albumin absorbed was greater than the amount of fibrinogen (comprised in the range of 70%-85% and 10%-22% respectively) and it is a good behaviour in terms of haemocompatibility. Cell culture tests showed good adhesion properties and a relative poor proliferation. In addition, a strong effect related to drug elution and a correlation with the macromolecular composition were detected. In this preliminary analysis, tested materials showed good characteristics and can be considered possible candidates to obtain coatings for drug-eluting stents. Highlights: Black-Right-Pointing-Pointer Preliminary evaluation of haemo- and cytocompatibility of newly-synthesised acrylic copolymers Black-Right-Pointing-Pointer Materials adsorb higher amounts of albumin and with a faster rate than fibrinogen. Black-Right-Pointing-Pointer Protein adsorption depended on the macromolecular composition and surface properties. Black-Right-Pointing-Pointer Cell viability on pure samples and efficacy of paclitaxel release were verified in C2C12 cultures.

  6. Antibacterial activity and cytocompatibility of Cu-Ti-O nanotubes.

    Science.gov (United States)

    Hang, Ruiqiang; Gao, Ang; Huang, Xiaobo; Wang, Xiaoguang; Zhang, Xiangyu; Qin, Lin; Tang, Bin

    2014-06-01

    TiO2 nanotubes (NTs) have favorable biological properties, but the poor antibacterial activity limits their application especially in orthopedics fields. In this article, Cu-Ti-O nanotubes with different Cu contents are fabricated on sputtered TiCu films. Scanning electron microscopy reveals the NTs can be formed on sputtered TiCu films when the Cu content is less than 14.6 at %. X-ray photoelectron spectroscopy results indicate the NTs are consist of CuO mixed with TiO2 and the Cu content in NTs decreases dramatically compared with that in TiCu films. Biological experiments show that although these NTs have poor release antibacterial activity, their contact antibacterial activity has proven to be excellent, indicating the NT surface can effectively inhibit biomaterial-associated infections. The cytocompatibility of the NTs is closely related to the Cu content and when its content is relatively low (1.01 at %), there is no appreciable cytotoxicity. So Cu-Ti-O NTs with 1 at % Cu may be suitable to achieve proper antibacterial activity and desired cytocompatibility. The Cu-Ti-O NTs integrate the favorable antibacterial activity of Cu and excellent biological properties of TiO2 NTs therefore have potential applications in orthopedics, dentistry, and other biomedical fields.

  7. Influence of modified polyester on the material properties of collagen-based biocomposites and in vitro evaluation of cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Chin-San, E-mail: t50008@cc.kyu.edu.tw

    2015-03-01

    The cytocompatibility of composite materials collagen (Col)/poly(hydroxyalkanoate) (PHA) and collagen/maleic anhydride-grafted PHA (PHA-g-MA) was investigated in this study. Col was homogeneously dispersed in the PHA-g-MA matrix as a result of condensation reactions. Mechanical characterisation indicated that the improved adhesion between Col and PHA-g-MA enhanced the tensile strength of the composite compared with that of PHA/Col. PHA-g-MA/Col composites were also more water-resistant than PHA/Col composites. Collagen and cell proliferation analysis indicated that PHA and PHA-g-MA and their composites were biocompatible with respect to FB proliferation. Cell-cycle and apoptosis assays by FBs on the PHA series composite samples were not affected by DNA content related to damage, i.e. rapid apoptosis/necrosis was not observed, demonstrating the potential of PHA/Col or PHA-g-MA/Col membranes for biomedical material applications. - Highlights: • Composites were prepared using polyester and collagen to explore their cytocompatibility. • The mechanical properties of the composite were significantly enhanced by the use of grafted polyester and collagen. • The polyester and collagen composites facilitated excellent cell viability and collagen production. • The cell cycle was not affected by DNA content related to damage, and it did not lead to rapid apoptosis or necrosis of the cells by the composite.

  8. Corrosion behavior and cytocompatibility of fluoride-incorporated plasma electrolytic oxidation coating on biodegradable AZ31 alloy

    Science.gov (United States)

    Tian, Peng; Peng, Feng; Wang, Donghui; Liu, Xuanyong

    2017-01-01

    Fluoride-incorporated plasma electrolytic oxidation (PEO) coating was fabricated on biodegradable AZ31 alloy. The surface morphologies and phases were investigated by scanning electron microscopy and X-ray diffraction. The effect of fluoride incorporation in coatings on corrosion behaviour was investigated in simulated body fluid and in vitro cytocompatibility of the coatings was also studied by evaluating cytotoxicity, adhesion, proliferation and live–dead stain of osteoblast cells (MC3T3-E1). Furthermore, the corrosion morphologies in vivo were examined. The results showed that the fluoride could be incorporated into the coating to form MgF2 phase. In vitro and in vivo degradation tests revealed that the corrosion resistance of the coating could be improved by the incorporation of fluoride, which may attribute to the chemical stability of MgF2 phase. Moreover, good cytocompatibility of fluoride-incorporated coating was confirmed with no obvious cytotoxicity, enhanced cell adhesion and proliferation. However, when the fluoride content was high, a slight inhibition of cell growth was observed. The results indicate that although fluoride incorporation can enhance the corrosion resistance of the coatings, thus resulting a more suitable environment for cells, the high content of fluoride in the coating also kill cells ascribed to the high released of fluorine. If the content of fluoride is well controlled, the PEO coating with MgF2 phase is a promising surface modification of Mg alloys. PMID:28149524

  9. Corrosion behavior and cytocompatibility of fluoride-incorporated plasma electrolytic oxidation coating on biodegradable AZ31 alloy.

    Science.gov (United States)

    Tian, Peng; Peng, Feng; Wang, Donghui; Liu, Xuanyong

    2017-02-01

    Fluoride-incorporated plasma electrolytic oxidation (PEO) coating was fabricated on biodegradable AZ31 alloy. The surface morphologies and phases were investigated by scanning electron microscopy and X-ray diffraction. The effect of fluoride incorporation in coatings on corrosion behaviour was investigated in simulated body fluid and in vitro cytocompatibility of the coatings was also studied by evaluating cytotoxicity, adhesion, proliferation and live-dead stain of osteoblast cells (MC3T3-E1). Furthermore, the corrosion morphologies in vivo were examined. The results showed that the fluoride could be incorporated into the coating to form MgF2 phase. In vitro and in vivo degradation tests revealed that the corrosion resistance of the coating could be improved by the incorporation of fluoride, which may attribute to the chemical stability of MgF2 phase. Moreover, good cytocompatibility of fluoride-incorporated coating was confirmed with no obvious cytotoxicity, enhanced cell adhesion and proliferation. However, when the fluoride content was high, a slight inhibition of cell growth was observed. The results indicate that although fluoride incorporation can enhance the corrosion resistance of the coatings, thus resulting a more suitable environment for cells, the high content of fluoride in the coating also kill cells ascribed to the high released of fluorine. If the content of fluoride is well controlled, the PEO coating with MgF2 phase is a promising surface modification of Mg alloys.

  10. Physicochemical properties and in vitro cytocompatibility of modified titanium surfaces prepared via micro-arc oxidation with different calcium concentrations

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Sui-Dan; Zhang, Hui [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China); Dong, Xu-Dong [Faculty of Pharmaceutical Sciences, University of British Columbia, Vancouver, BC V6T 1Z3 (Canada); Ning, Cheng-Yun [College of Material Science and Engineering, South China University of Technology, Guangzhou 510641 (China); Fok, Alex S.L. [Minnesota Dental Research Center of Biomaterials and Biomechanics, School of Dentistry, University of Minnesota, Minneapolis, MN 55414 (United States); Wang, Yan, E-mail: wyan65@163.com [Guanghua School of Stomatology, Hospital of Stomatology, Guangdong Key Laboratory of Stomatology, Sun Yat-sen University, Guangzhou 510055 (China)

    2015-02-28

    Highlights: • MAO coating improves the surface characteristics and cytocompatibility of titanium. • Composition of MAO coating varies with the electrolyte concentration. • MAO coating properties can be optimized by adjusting the electrolyte concentration. • Higher CA concentration contributes to more favorable MAO coating cytocompatibility. - Abstract: Objective: To explore the effect of calcium concentration in the electrolyte solution on the physicochemical properties and biocompatibility of coatings formed by micro-arc oxidation (MAO) on titanium surfaces. Methods: The surfaces of pure titanium plates were modified by MAO in an electrolytic solution containing calcium acetate (CA; C{sub 4}H{sub 6}CaO{sub 4}) at concentrations of 0.05, 0.1, 0.2, or 0.3 M and β-glycerophosphate disodium salt pentahydrate (β-GP; C{sub 3}H{sub 7}Na{sub 2}O{sub 6}P·5H{sub 2}O) at a fixed concentration of 0.02 M. Surface topography, elemental characteristics, phase composition, and roughness were investigated by scanning electron microscopy, energy-dispersive X-ray analysis, X-ray diffraction, and a surface roughness tester, respectively. To assess the cytocompatibility and osteoinductivity of the surfaces, MC3T3-E1 preosteoblasts were cultured on the surfaces in vitro, and cell morphology, adhesion, proliferation, and differentiation were observed. Results: The porous MAO coating was composed primarily of TiO{sub 2} rutile and anatase. The amount of TiO{sub 2} rutile, the Ca/P ratio, and the surface roughness of the MAO coating increased with increasing CA concentration in the electrolyte solution. Ca{sub 3}(PO{sub 4}){sub 2}, CaCO{sub 3}, and CaTiO{sub 3} were formed on MAO-treated surfaces prepared with CA concentrations of 0.2 and 0.3 M. Cell proliferation and differentiation increased with increasing CA concentration, with MC3T3-E1 cells exhibiting favorable morphologies for bone–implant integration. Conclusions: MAO coating improves the surface characteristics and

  11. In vitro degradation behavior and cytocompatibility of biodegradable AZ31 alloy with PEO/HT composite coating.

    Science.gov (United States)

    Tian, Peng; Liu, Xuanyong; Ding, Chuanxian

    2015-04-01

    Biodegradable magnesium-based implants have attracted much attention recently in orthopedic applications because of their good mechanical properties and biocompatibility. However, their rapid degradation in vivo will not only reduce their mechanical strength, but also induce some side effects, such as local alkalization and gas cavity, which may lead to a failure of the implant. In this work, a hydroxyapatite (HA) layer was prepared on plasma electrolytic oxidization (PEO) coating by hydrothermal treatment (HT) to fabricate a PEO/HT composite coating on biodegradable AZ31 alloy. The in vitro degradation behaviors of all samples were evaluated in simulated body fluid (SBF) and their surface cytocompatibility was also investigated by evaluating the adhesion and proliferation of osteoblast cells (MC3T3-E1). The results showed that the HA layer consisted of a dense inner layer and a needle-like outer layer, which successfully sealed the PEO coating. The in vitro degradation tests showed that the PEO/HT composite coating improved the corrosion resistance of AZ31 alloy in SBF, presenting nearly no severe local alkalization and hydrogen evolution. The lasting corrosion resistance of the PEO/HT composite coating may attribute to the new hydroxyapatite formation during the degradation process. Moreover, compared with AZ31 alloy and PEO coating, PEO/HT composite coating was more suitable for cells adhesion and proliferation, indicating improved surface cytocompatibility. The results show that the PEO/HT composite coating is promising as protective coating on biodegradable magnesium-based implants to enhance their corrosion resistance as well as improve their surface cytocompatibility for orthopedic applications.

  12. Preparation and preliminary cytocompatibility of magnesium doped apatite cement with degradability for bone regeneration.

    Science.gov (United States)

    Lu, Jingxiong; Wei, Jie; Yan, Yonggang; Li, Hong; Jia, Junfeng; Wei, Shicheng; Guo, Han; Xiao, Tiqiao; Liu, Changsheng

    2011-03-01

    In the present study, we fabricated magnesium doped apatite cement (md-AC) with rapid self-setting characteristic by adding the mixed powders of magnesium oxide and calcium dihydrogen phosphate (MO-CDP) into hydroxyapatite cement (HAC). The results revealed that the md-AC with 50 wt% MO-CDP could set within 6 min and the compression strength could reach 51 MPa after setting for 1 h, indicating that the md-AC had highly initial mechanical strength. The degradability of the md-AC in Tris-HCl solution increased with the increase of MO-CDP amount, and the weight loss ratio of md-AC with 50 wt% MO-CDP was 57.5 wt% after soaked for 12 weeks. Newly flake-like apatite could be deposited on the md-AC surfaces after soaked in simulated body fluid (SBF) for 7 days. Cell proliferation ratio of MG(63) cells on md-AC was obviously higher than that of HAC on days 4 and 7. The cells with normal phenotype spread well on the md-AC surfaces and attached intimately with the substrate, and alkaline phosphatase (ALP) activity of the cells on md-AC significantly improved compared with HAC on day 7. The results demonstrate that the md-AC has a good ability to support cell proliferation and differentiation, and indicate a good cytocompatibility.

  13. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    Directory of Open Access Journals (Sweden)

    Birgit Huber

    2016-04-01

    Full Text Available Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM, biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap® technology by the authors.

  14. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization

    Science.gov (United States)

    Huber, Birgit; Engelhardt, Sascha; Meyer, Wolfdietrich; Krüger, Hartmut; Wenz, Annika; Schönhaar, Veronika; Tovar, Günter E. M.; Kluger, Petra J.; Borchers, Kirsten

    2016-01-01

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM), biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap® technology by the authors. PMID:27104576

  15. Polydopamine-Templated Hydroxyapatite Reinforced Polycaprolactone Composite Nanofibers with Enhanced Cytocompatibility and Osteogenesis for Bone Tissue Engineering.

    Science.gov (United States)

    Gao, Xiang; Song, Jinlin; Ji, Ping; Zhang, Xiaohong; Li, Xiaoman; Xu, Xiao; Wang, Mengke; Zhang, Siqi; Deng, Yi; Deng, Feng; Wei, Shicheng

    2016-02-10

    Nanohydroxyapatite (HA) synthesized by biomimetic strategy is a promising nanomaterial as bone substitute due to its physicochemical features similar to those of natural nanocrystal in bone tissue. Inspired by mussel adhesive chemistry, a novel nano-HA was synthesized in our work by employing polydopamine (pDA) as template under weak alkaline condition. Subsequently, the as-prepared pDA-templated HA (tHA) was introduced into polycaprolactone (PCL) matrix via coelectrospinning, and a bioactive tHA/PCL composite nanofiber scaffold was developed targeted at bone regeneration application. Our research showed that tHA reinforced PCL composite nanofibers exhibited favorable cytocompatibility at given concentration of tHA (0-10 w.t%). Compared to pure PCL and traditional nano-HA enriched PCL (HA/PCL) composite nanofibers, enhanced cell adhesion, spreading and proliferation of human mesenchymal stem cells (hMSCs) were observed on tHA/PCL composite nanofibers on account of the contribution of pDA present in tHA. More importantly, tHA nanoparticles exposed on the surface of composite nanofibers could further promote osteogenesis of hMSCs in vitro even in the absence of osteogenesis soluble inducing factors when compared to traditional HA/PCL scaffolds, which was supported by in vivo test as well according to the histological analysis. Overall, our study demonstrated that the developed tHA/PCL composite nanofibers with enhanced cytocompatibility and osteogenic capacity hold great potential as scaffolds for bone tissue engineering.

  16. Blood-Vessel Mimicking Structures by Stereolithographic Fabrication of Small Porous Tubes Using Cytocompatible Polyacrylate Elastomers, Biofunctionalization and Endothelialization.

    Science.gov (United States)

    Huber, Birgit; Engelhardt, Sascha; Meyer, Wolfdietrich; Krüger, Hartmut; Wenz, Annika; Schönhaar, Veronika; Tovar, Günter E M; Kluger, Petra J; Borchers, Kirsten

    2016-04-20

    Blood vessel reconstruction is still an elusive goal for the development of in vitro models as well as artificial vascular grafts. In this study, we used a novel photo-curable cytocompatible polyacrylate material (PA) for freeform generation of synthetic vessels. We applied stereolithography for the fabrication of arbitrary 3D tubular structures with total dimensions in the centimeter range, 300 µm wall thickness, inner diameters of 1 to 2 mm and defined pores with a constant diameter of approximately 100 µm or 200 µm. We established a rinsing protocol to remove remaining cytotoxic substances from the photo-cured PA and applied thio-modified heparin and RGDC-peptides to functionalize the PA surface for enhanced endothelial cell adhesion. A rotating seeding procedure was introduced to ensure homogenous endothelial monolayer formation at the inner luminal tube wall. We showed that endothelial cells stayed viable and adherent and aligned along the medium flow under fluid-flow conditions comparable to native capillaries. The combined technology approach comprising of freeform additive manufacturing (AM), biomimetic design, cytocompatible materials which are applicable to AM, and biofunctionalization of AM constructs has been introduced as BioRap(®) technology by the authors.

  17. Cytocompatibility of magnesium alloys after surface fluoridation tested by human bone marrow mesenchymal cells%人骨髓间充质干细胞检测表面氟化处理镁合金材料的细胞相容性

    Institute of Scientific and Technical Information of China (English)

    姜海英; 闫征斌; 张照; 艾红军

    2011-01-01

    BACKGROUND: AZ31B magnesium alloy with surface flouridization is a new type of magnesium alloy developed by Institute of Metal Research, Chinese Academy of Sciences. Its biocompatibility is unclear.OBJECTIVE: To observe the cytocompatibility of magnesium alloys with surface fluoridation tested by human bone marrow mesenchymal cells (BMSCs).METHODS: Human BMSCs were identified and cultured. The AZ31B magnesium alloy was taken as control and the AZ31B magnesium alloy with surface fluoridation was experimental group. Human BMSCs were the test cells. Leaching liquor of the alloy in both groups was used for cell compatibility experiments in vitro in order to evaluate the biocompatibility of AZ31B magnesium alloy.RESULTS AND CONCLUSION: The cell survival rate of AZ31B magnesium alloys with surface fluoridation was significantly higher than AZ31B magnesium alloys without surface fluoridation. The toxicity of cells in the leaching liquor of AZ31B magnesium alloys with surface fluoridation was Grade 1 and was non-toxic to the basic cell growth. The biocompatibility of the AZ31B magnesium alloys with surface fluoridation is superior to the AZ31B magnesium alloys without surface fluoridation.%背景:表面氟化处理的AZ31B镁合金是中科院金属研究所新研制的镁合金,是否具有良好的生物相容性尚不确切.目的:以人骨髓间充质干细胞作为检测细胞,评价表面氟处理的镁合金材料的细胞相容性.方法:人骨髓间充质干细胞培养并予以鉴定,将镁合金AZ31B作为对照组,氟处理的镁合金AZ31B材料为实验组.以人骨髓间充质干细胞作为检测细胞,取两组材料浸提液进行体外细胞相容性实验,评价氟处理的镁合金AZ31B材料的生物相容性.结果与结论:与未经氟处理镁合金AZ31B材料相比,经氟处理镁合金AZ31B材料能显著提高细胞存活率,细胞毒性分级1级,对细胞生长基本无毒性作用.结果表明,经氟处理镁合金AZ31B材料生物相容性

  18. In Vitro Corrosion and Cytocompatibility of ZK60 Magnesium Alloy Coated with Hydroxyapatite by a Simple Chemical Conversion Process for Orthopedic Applications

    Directory of Open Access Journals (Sweden)

    Bing Wang

    2013-12-01

    Full Text Available Magnesium and its alloys—a new class of degradable metallic biomaterials—are being increasingly investigated as a promising alternative for medical implant and device applications due to their advantageous mechanical and biological properties. However, the high corrosion rate in physiological environments prevents the clinical application of Mg-based materials. Therefore, the objective of this study was to develop a hydroxyapatite (HA coating on ZK60 magnesium alloy substrates to mediate the rapid degradation of Mg while improving its cytocompatibility for orthopedic applications. A simple chemical conversion process was applied to prepare HA coating on ZK60 magnesium alloy. Surface morphology, elemental compositions, and crystal structures were characterized using scanning electron microscopy, energy dispersive spectroscopy, and X-ray diffraction, respectively. The corrosion properties of samples were investigated by immersion test and electrochemical test. Murine fibroblast L-929 cells were harvested and cultured with coated and non-coated ZK60 samples to determine cytocompatibility. The degradation results suggested that the HA coatings decreased the degradation of ZK60 alloy. No significant deterioration in compression strength was observed for all the uncoated and coated samples after 2 and 4 weeks’ immersion in simulated body fluid (SBF. Cytotoxicity test indicated that the coatings, especially HA coating, improved cytocompatibility of ZK60 alloy for L929 cells.

  19. Cytocompatibility and antibacterial properties of zirconia coatings with different silver contents on titanium

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Heng-Li [School of Dentistry, China Medical University, Taichung 404, Taiwan (China); Chang, Yin-Yu, E-mail: yinyu@mail2000.com.tw [Department of Mechanical and Computer-Aided Engineering, National Formosa University, Yunlin 632, Taiwan (China); Chen, Ya-Chi [Department of Materials Science and Engineering, Mingdao University, Changhua 52345, Taiwan (China); Lai, Chih-Ho [School of Medicine, China Medical University, Taichung 404, Taiwan (China); Chen, Michael Y.C. [School of Dentistry, China Medical University, Taichung 404, Taiwan (China); Division of Oral and Maxillofacial Surgery, China Medical University Hospital, Taichung 404, Taiwan (China)

    2013-12-31

    This study used a twin-gun magnetron sputtering system to deposit ZrO{sub 2}-silver (Ag) coatings on biograde pure-titanium implant materials, and the Ag content in the deposited coatings was controlled by the magnetron power. The films were then annealed using rapid thermal annealing at 350 °C for 2 min to induce the nucleation and growth of nanoparticles on the film surface. Staphylococcus aureus (S. aureus) and Actinobacillus actinomycetemcomitans (A. actinomycetemcomitans) were used for in vitro antibacterial analyses. The cytocompatibility, mRNA expression, and adhesive morphology of human gingival fibroblast (HGF) cells on the coatings were also determined. The obtained results suggest that ZrO{sub 2}-Ag composite coatings containing less than 10.6 at.% Ag show hydrophobicity, good viability and proliferation of HGF cells, and antibacterial effects on S. aureus and A. actinomycetemcomitans. Moreover, the antibacterial performance of ZrO{sub 2}-Ag coatings is superior to that pure-titanium whilst maintaining biological compatibility. - Highlights: • The annealed ZrO{sub 2}-Ag coatings showed a tetragonal-and-monoclinic structure. • Nanoparticles were well distributed in the annealed ZrO{sub 2}-Ag composite coatings. • The ZrO{sub 2}-Ag coated Ti showed hydrophobic feature. • The ZrO{sub 2}-Ag showed good antibacterial performance. • The ZrO{sub 2}-Ag showed good human gingival fibroblast cell viability.

  20. In situ plasma fabrication of ceramic-like structure on polymeric implant with enhanced surface hardness, cytocompatibility and antibacterial capability.

    Science.gov (United States)

    Liu, Jun; Zhang, Wei; Shi, Haigang; Yang, Kun; Wang, Gexia; Wang, Pingli; Ji, Junhui; Chu, Paul K

    2016-05-01

    Polymeric materials are commonly found in orthopedic implants due to their unique mechanical properties and biocompatibility but the poor surface hardness and bacterial infection hamper many biomedical applications. In this study, a ceramic-like surface structure doped with silver is produced by successive plasma implantation of silicon (Si) and silver (Ag) into the polyamine 66 (PA66) substrate. Not only the surface hardness and elastic modulus are greatly enhanced due to the partial surface carbonization and the ceramic-like structure produced by the reaction between energetic Si and the carbon chain of PA66, but also the antibacterial activity is improved because of the combined effects rendered by Ag and SiC structure. Furthermore, the modified materials which exhibit good cytocompatibility upregulate bone-related genes and proteins expressions of the contacted bone mesenchymal stem cells (BMSCs). For the first time, it explores out that BMSCs osteogenesis on the antibacterial ceramic-like structure is mediated via the iNOS and nNOS signal pathways. The results reveal that in situ plasma fabrication of an antibacterial ceramic-like structure can endow PA66 with excellent surface hardness, cytocompatibility, as well as antibacterial capability.

  1. Cytocompatibility of novel extracellular matrix protein analogs of biodegradable polyester polymers derived from α-hydroxy amino acids.

    Science.gov (United States)

    Lecht, Shimon; Cohen-Arazi, Naomi; Cohen, Gadi; Ettinger, Keren; Momic, Tatjana; Kolitz, Michal; Naamneh, Majdi; Katzhendler, Jehoshua; Domb, Abraham J; Lazarovici, Philip; Lelkes, Peter I

    2014-01-01

    One of the challenges in regenerative medicine is the development of novel biodegradable materials to build scaffolds that will support multiple cell types for tissue engineering. Here we describe the preparation, characterization, and cytocompatibility of homo- and hetero-polyesters of α-hydroxy amino acid derivatives with or without lactic acid conjugation. The polymers were prepared by a direct condensation method and characterized using gel permeation chromatography, (1)H-nuclear magnetic resonance spectroscopy, Fourier transform infrared spectroscopy, differential scanning calorimetry, optical activity, and solubility. The surface charge of the polymers was evaluated using zeta potential measurements. The polymers were coated onto glass cover slips followed by characterization using nano-surface profiler, thin film reflectometry, and atomic force microscopy (AFM). Their interaction with endothelial and neuronal cells was assessed using adhesion, proliferation, and differentiation assays. Of the characterized polymers, Poly-HOVal-LA, but not Poly-(D)HOPhe, significantly augmented nerve growth factor (NGF)-induced neuronal differentiation of the PC12 pheochromcytoma cells. In contrast, Poly-HOLeu increased by 20% the adhesion of endothelial cells, but did not affect PC12 cell differentiation. NGF-induced Erk1/2 phosphorylation in PC12 cells grown on the different polymers was similar to the effect observed for cells cultured on collagen type I. While no significant association could be established between charge and the differentiative/proliferative properties of the polymers, AFM analysis indicated augmentation of NGF-induced neuronal differentiation on smooth polymer surfaces. We conclude that overall selective cytocompatibility and bioactivity might render α-hydroxy amino acid polymers useful as extracellular matrix-mimicking materials for tissue engineering.

  2. Antibacterial properties and cytocompatibility of tantalum oxide coatings with different silver content

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Heng-Li [School of Dentistry, China Medical University, Taichung 404, Taiwan (China); Chang, Yin-Yu, E-mail: yinyu@mail2000.com.tw; Chen, Hung-Jui; Chou, Yu-Kai [Department of Mechanical and Computer-Aided Engineering, National Formosa University, Yunlin 632, Taiwan (China); Lai, Chih-Ho [School of Medicine, China Medical University, Taichung 404, Taiwan (China); Chen, Michael Y. C. [Division of Oral and Maxillofacial Surgery, China Medical University Hospital, Taichung 404, Taiwan (China)

    2014-03-15

    Tantalum (Ta) oxides and their coatings have been proved to increase their applications in the biomedical fields by improving osseointegration and wear resistance. In this study, Ta oxide coatings containing different proportions of Ag are deposited on SS304 materials. A twin-gun magnetron sputtering system is used to deposit the tantalum oxide-Ag coating. In this study, Staphylococcus aureus, which exhibits physiological commensalism on the human skin, nares, and mucosal and oral areas, is chosen as the model for in vitro antibacterial analyses via a fluorescence staining method using Syto9. The cytocompatibility and adhesive morphology of human skin fibroblast cells (CCD-966SK) on the coatings are also determined by using the microculture tetrazolium assay. This study shows that Ta{sub 2}O{sub 5} and Ta{sub 2}O{sub 5}-Ag coatings with 12.5 at. % of Ag exhibit improved antibacterial effects against S. aureus and have good skin fibroblast cell cellular biocompatibility.

  3. Effect of Boron Addition on the Thermal, Degradation, and Cytocompatibility Properties of Phosphate-Based Glasses

    Directory of Open Access Journals (Sweden)

    Nusrat Sharmin

    2013-01-01

    Full Text Available In this study eight different phosphate-based glass compositions were prepared by melt-quenching: four in the (P2O545-(CaO16--(MgO24- system and four in the system (P2O550-(CaO16--(MgO24-, where and 10 mol%. The effect of B2O3 addition on the thermal properties, density, molar volume, dissolution rates, and cytocompatibility were studied for both glass systems. Addition of B2O3 increased the glass transition (, crystallisation (, melting (, Liquidus ( and dilatometric softening ( temperature and molar volume (. The thermal expansion coefficient (α and density ( were seen to decrease. An assessment of the thermal stability of the glasses was made in terms of their processing window (crystallisation onset, minus glass transition temperature, , and an increase in the processing window was observed with increasing B2O3 content. Degradation studies of the glasses revealed that the rates decreased with increasing B2O3 content and a decrease in degradation rates was also observed as the P2O5 content reduced from 50 to 45 mol%. MG63 osteoblast-like cells cultured in direct contact with the glass samples for 14 days revealed comparative data to the positive control for the cell metabolic activity, proliferation, ALP activity, and morphology for glasses containing up to 5 mol% of B2O3.

  4. Graphene oxide-reinforced biodegradable genipin-cross-linked chitosan fluorescent biocomposite film and its cytocompatibility

    Directory of Open Access Journals (Sweden)

    Li JH

    2013-09-01

    Full Text Available Jianhua Li,1 Na Ren1, Jichuan Qiu,1 Xiaoning Mou,2 Hong Liu1,21Center of Bio and Micro/Nano Functional Materials, State Key Laboratory of Crystal Materials, Shandong University, Jinan, People's Republic of China; 2Beijing Institute of Nanoenergy and Nanosystems, Chinese Academy of Sciences, Beijing, People's Republic of ChinaAbstract: A genipin-cross-linked chitosan/graphene oxide (GCS/GO composite film was prepared using a solution casting method. Fourier transform infrared (FTIR and ultraviolet-visible (UV-Vis spectroscopy of the composite films showed that the interactions between the CS and oxygen-containing groups of GO resulted in good dispersion of the GO sheets in the CS network. The addition of GO decreased the expansion ratio of the composite films in physiological conditions and increased the resistance to degradation by lysozymes in vitro. As well, the tensile strength values of the GCS/GO films were significantly increased with the increasing load of GO. Moreover, the GCS/GO composite film also maintained the intrinsic fluorescence of GCS. The in vitro cell study results revealed that the composite films were suitable for the proliferation and adhesion of mouse preosteoblast (MC3T3-E1 cells. The GCS/GO biocomposite films might have a potential use in tissue engineering, bioimaging, and drug delivery.Keywords: chitosan film degradation, fluorescence, cytocompatibility

  5. Fabrication and cytocompatibility of spherical magnesium ammonium phosphate granules.

    Science.gov (United States)

    Christel, Theresa; Geffers, Martha; Klammert, Uwe; Nies, Berthold; Höß, Andreas; Groll, Jürgen; Kübler, Alexander C; Gbureck, Uwe

    2014-09-01

    Magnesium phosphate compounds, as for example struvite (MgNH4PO4·6H2O), have comparable characteristics to calcium phosphate bone substitutes, but degrade faster under physiological conditions. In the present work, we used a struvite forming calcium doped magnesium phosphate cement with the formulation Ca0.75Mg2.25(PO4)2 and an ammonium phosphate containing aqueous solution to produce round-shaped granules. For the fabrication of spherical granules, the cement paste was dispersed in a lipophilic liquid and stabilized by surfactants. The granules were characterized with respect to morphology, size distribution, phase composition, compressive strength, biocompatibility and solubility. In general, it was seen that small granules can hardly be produced by means of emulsification, when the raw material is a hydraulic paste, because long setting times promote coalescence of initially small unhardened cement droplets. Here, this problem was solved by using an aqueous solution containing both the secondary (NH4)2HPO4 and primary ammonium phosphates NH4H2PO4 to accelerate the setting reaction. This resulted in granules with 97 wt.% having a size in the range between 200 and 1,000 μm. The novel solution composition doubled the compressive strength of the cement to 37 ± 5 MPa without affecting either the conversion to struvite or the cytocompatibility using human fetal osteoblasts.

  6. Regular pattern formation on surface of aromatic polymers and its cytocompatibility

    Science.gov (United States)

    Michaljaničová, I.; Slepička, P.; Rimpelová, S.; Slepičková Kasálková, N.; Švorčík, V.

    2016-05-01

    In this work, we describe ripple and dot nanopatterning of three different aromatic polymer substrates by KrF excimer laser treatment. The conditions for regular structures were established by laser fluence and number of pulses. Subsequently, the influence of the angle of incidence of a laser beam was investigated. We have chosen polyethersulfone (PES), polyetherimide (PEI) and polyetheretherketone (PEEK) as substrates for modification since they are thermally, chemically and mechanically resistant aromatic polymers with high absorption coefficients at excimer laser wavelength. As a tool of wettability investigation, we used contact angle measurement and for determination of the absorption edge, UV-vis spectroscopy was used. Material surface chemistry was analyzed using FTIR and the changes caused by modification were gained as differential spectra by subtraction of the spectra of non-modified material. Surface morphology was investigated by atomic force microscopy, also the roughness and surface area of modified samples were studied. The scans showed the formation of regular periodic structures, ripples and dots, after treatment by 8 and 16 mJ cm-2 and 6000 pulses. Further, initial in vitro cytocompatibility tests were performed using U-2 OS cell line growing on PES samples subjected to scanning electron microscopy analysis. The structure formation mapping contributes strongly to development of new applications using nanostructured polymers, e.g. in tissue engineering or in combination with metallization in selected electronics and metamaterials construction.

  7. Cytocompatibility and antibacterial activity of titania nanotubes incorporated with gold nanoparticles.

    Science.gov (United States)

    Yang, Tingting; Qian, Shi; Qiao, Yuqing; Liu, Xuanyong

    2016-09-01

    TiO2 nanotubes prepared by electrochemical anodization have received considerable attention in the biomedical field. In this work, different amounts of gold nanoparticles were immobilized onto TiO2 nanotubes using 3-aminopropyltrimethoxysilane as coupling agent. Field emission scanning electron microscopy and X-ray photoelectron spectroscopy were used to investigate the surface morphology and composition. Photoluminescence spectra and surface zeta potential were also measured. The obtained results indicate that the surface modified gold nanoparticles can significantly enhance the electron storage capability and reduce the surface zeta potential compared to pristine TiO2 nanotubes. Moreover, the surface modified gold nanoparticles can stimulate initial adhesion and spreading of rat bone mesenchymal stem cells as well as proliferation, while the osteogenous performance of TiO2 nanotubes will not be reduced. The gold-modified surface presents moderate antibacterial effect on both Staphylococcus aureus and Escherichia coli. It should be noted that the surface modified fewer gold nanoparticles has better antibacterial effect compared to the surface of substantial modification of gold nanoparticles. Our study illustrates a composite surface with favorable cytocompatibility and antibacterial effect and provides a promising candidate for orthopedic and dental implant.

  8. Mechanical Properties and Cytocompatibility Improvement of Vertebroplasty PMMA Bone Cements by Incorporating Mineralized Collagen

    Directory of Open Access Journals (Sweden)

    Hong-Jiang Jiang

    2015-05-01

    Full Text Available Polymethyl methacrylate (PMMA bone cement is a commonly used bone adhesive and filling material in percutaneous vertebroplasty and percutaneous kyphoplasty surgeries. However, PMMA bone cements have been reported to cause some severe complications, such as secondary fracture of adjacent vertebral bodies, and loosening or even dislodgement of the set PMMA bone cement, due to the over-high elastic modulus and poor osteointegration ability of the PMMA. In this study, mineralized collagen (MC with biomimetic microstructure and good osteogenic activity was added to commercially available PMMA bone cement products, in order to improve both the mechanical properties and the cytocompatibility. As the compressive strength of the modified bone cements remained well, the compressive elastic modulus could be significantly down-regulated by the MC, so as to reduce the pressure on the adjacent vertebral bodies. Meanwhile, the adhesion and proliferation of pre-osteoblasts on the modified bone cements were improved compared with cells on those unmodified, such result is beneficial for a good osteointegration formation between the bone cement and the host bone tissue in clinical applications. Moreover, the modification of the PMMA bone cements by adding MC did not significantly influence the injectability and processing times of the cement.

  9. In vitro hemocompatibility and cytocompatibility of dexamethasone-eluting PLGA stent coatings

    Science.gov (United States)

    Zhang, Jiang; Liu, Yang; Luo, Rifang; Chen, Si; Li, Xin; Yuan, Shuheng; Wang, Jin; Huang, Nan

    2015-02-01

    Drug-eluting stents (DESs) have been an important breakthrough for interventional cardiology applications since 2002. Though successful in reducing restenosis, some adverse clinical problems still emerged, which were mostly caused by the bare-metal stents and non-biodegradable polymer coatings, associated with the delayed endothelialization process. In this study, dexamethasone-loaded poly (lactic-co-glycolic acid) (PLGA) coatings were developed to explore the potential application of dexamethasone-eluting stents. Dexamethasone-eluting PLGA stents were prepared using ultrasonic atomization spray method. For other tests like stability and cytocompatibility and hemocompatibility tests, dexamethasone loaded coatings were deposited on 316L SS wafers. Fourier transform-infrared spectroscopy (FT-IR) results demonstrated that there was no chemical reaction between PLGA and dexamethasone. The balloon expansion experiment and surface morphology observation suggested that the stent coatings were smooth and uniform, and could also withstand the compressive and tensile strains imparted without cracking after stent expansion. The drug release behavior in vitro indicated that dexamethasone existed burst release within 1 day, but it presented linear release characteristics after 6 days. In vitro platelets adhesion, activation test and APTT test were also done, which showed that after blending dexamethasone into PLGA, the hemocompatibility was improved. Besides, dexamethasone and dexamethasone-loaded PLGA coatings could significantly inhibit the attachment and proliferation of smooth muscle cells.

  10. Hydrophobic modification of polymethyl methacrylate as intraocular lenses material to improve the cytocompatibility.

    Science.gov (United States)

    Wang, Bailiang; Lin, Quankui; Shen, Chenghui; Tang, Junmei; Han, Yuemei; Chen, Hao

    2014-10-01

    The development of posterior capsule opacification (PCO) after intraocular lenses (IOL) implantation for dealing with cataract is mainly due to the severe loss of the human lens epithelial cells (HLECs) during surgery contact. A novel poly (hedral oligomeric silsesquioxane-co-methyl methacrylate) copolymer (allyl POSS-PMMA) was synthesized by free radical polymerization method to promote the adhesion of HLECs. FT-IR and (1)H NMR measurements indicated the existence of POSS cage in the product, which demonstrated the successful synthesis of allyl POSS-PMMA copolymer. Effect of allyl POSS in the hybrids on crystal structure, surface wettability and morphology, optical transmission, thermodynamic properties and cytocompatibility was investigated in detail. X-ray diffraction peaks at 2θ∼11° and 12° indicated that POSS molecules had aggregated and crystallized. Thermogravimetric analysis-differential scanning calorimeter and optical transmission measurements confirmed that the allyl POSS-PMMA copolymer had high glass transition temperatures (more than 100°C) and good transparency. The hydrophilicity and morphology of PMMA and copolymers surfaces were characterized by static water contact angle and atomic force microscopy. The results revealed that the surface of the allyl POSS-PMMA copolymer displayed higher hydrophobicity and higher roughness than that of pure PMMA. The surface biocompatibility was evaluated by morphology and activity measurement with HLECs in vitro. The results verified that the surface of allyl POSS-PMMA copolymer films had more HLECs adhesion and better spreading morphology than that of PMMA film.

  11. Chitosan-based gels as bioactive carriers for bone marrow mesenchymal stem cells:A cytocompatibility study%壳聚糖凝胶活性载体与骨髓间充质干细胞的相容性

    Institute of Scientific and Technical Information of China (English)

    李忠; 杨柳; 戴刚; 王富友; 金旭红; 段小军

    2008-01-01

    BACKGROUND: Chitosan-disodium β-glycerol phosphate (C/GP) gel has been shown to be compatible with the entrapment of viable chondrocytes, and bone marrow mesenchymal stem cells (BMSCs) are considered to be the potential cells used in tissue engineering. This experiment is aimed to observe the cytocompatibility of BMSCs with C/GP gel.OBJECTIVE: To study the effect of C/GP gel on the growth, proliferation and chondrogenic differentiation in vitro cultured BMSCs and explore a new carrier for the application of cartilage tissue engineering.DESIGN: Completely randomized controlled experiment.SETTING: Department of Bone and Joint Surgery, Affiliated Hospital of Luzhou Medical College; Center Laboratory of Southwest Hospital Affiliated to the Third Military Medical University of Chinese PLA.MATERIALS: The experiment was performed in Center Laboratory of Southwest Hospital Affiliated to the Third Military Medical University of Chinese PLA between October 2005 and April 2006, Six adult female mini-pigss were employed. C/GP gel is prepared by mixture the HCI solution of chitosan with salt solution of β-glycerol phosphate, allowed gel at 37 ℃ in incubator for about 5 to 10 minutes.METHODS: ① BMSCs culture: 4-6 mL of bone marrow harvested from the posterior superior lilac crest were plated at 20 ×10/100 mm dish and then grown for 14 days in complete media, consisting of DMEM/F-12 supplemented with 10% fetal ovine serum. Cells were harvested and re-seeded for subculture. ② BMSCs differentiation assays: Osteogenic differentiation was assessed by histologic detection of alkaline phosphatase activity and calcium in cultures under osteogenic conditions. Chondrogenic differentiation was evaluated by histology for toluidine blue and immunohistochemistry for type Ⅱ collagen in cultures under chondrogenic conditions. ③ In vitro assays, expanded BMSCs were suspended in C/GP solution and allowed gel at 37 ℃ in incubator for about 5 to 10 minutes, then cultured under

  12. Barium Titanate Nanoparticles: Highly Cytocompatible Dispersions in Glycol-chitosan and Doxorubicin Complexes for Cancer Therapy

    Science.gov (United States)

    Ciofani, Gianni; Danti, Serena; D'Alessandro, Delfo; Moscato, Stefania; Petrini, Mario; Menciassi, Arianna

    2010-07-01

    In the latest years, innovative nanomaterials have attracted a dramatic and exponentially increasing interest, in particular for their potential applications in the biomedical field. In this paper, we reported our findings on the cytocompatibility of barium titanate nanoparticles (BTNPs), an extremely interesting ceramic material. A rational and systematic study of BTNP cytocompatibility was performed, using a dispersion method based on a non-covalent binding to glycol-chitosan, which demonstrated the optimal cytocompatibility of this nanomaterial even at high concentration (100 μg/ml). Moreover, we showed that the efficiency of doxorubicin, a widely used chemotherapy drug, is highly enhanced following the complexation with BTNPs. Our results suggest that innovative ceramic nanomaterials such as BTNPs can be realistically exploited as alternative cellular nanovectors.

  13. Cytocompatibility evaluation of NiMnSn meta-magnetic shape memory alloys for biomedical applications.

    Science.gov (United States)

    Guiza-Arguello, Viviana R; Monroe, James A; Karaman, Ibrahim; Hahn, Mariah S

    2016-07-01

    Recently, magnetic shape memory alloys (MSMAs) have emerged as an interesting extension to conventional shape memory alloys (SMAs) due to their capacity to undergo reversible deformation in response to an externally applied magnetic field. Meta-magnetic SMAs (M-MSMAs) are a class of MSMAs that are able to transform magnetic energy to mechanical work by harnessing a magnetic-field induced phase transformation, and thus have the capacity to impose up to 10 times greater stress than conventional MSMAs. As such, M-MSMAs may hold substantial promise in biomedical applications requiring extracorporeal device activation. In the present study, the cytotoxicity and ion release from an Ni50 Mn36 Sn14 atomic percent composition M-MSMA were evaluated using NIH/3T3 fibroblasts. Initial studies showed that the viability of cells exposed to NiMnSn ion leachants was 60 to 67% of tissue culture polystyrene (TCP) controls over 10 to 14 days of culture. This represents a significant improvement in cytocompatibility relative to NiMnGa alloys, one of the most extensively studied MSMA systems, which have been reported to induce 80% cell death in only 48 h. Furthermore, NiMnSn M-MSMA associated cell viability was increased to 80% of TCP controls following layer-by-layer alloy coating with poly(allylamine hydrochloride)/poly(acrylic acid) [PAH/PAA]. Ion release measures revealed that the PAH/PAA coatings decreased total Sn and Mn ion release by 50% and 25%, respectively, and optical microscopy evaluation indicated that the coatings reduced NiMnSn surface oxidation. To our knowledge, this study presents the first cytotoxicity evaluation of NiMnSn M-MSMAs and lays the groundwork for their further biological evaluation. © 2015 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 104B: 853-863, 2016.

  14. Novel tricalcium silicate/magnesium phosphate composite bone cement having high compressive strength, in vitro bioactivity and cytocompatibility.

    Science.gov (United States)

    Liu, Wenjuan; Zhai, Dong; Huan, Zhiguang; Wu, Chengtie; Chang, Jiang

    2015-07-01

    Although inorganic bone cements such as calcium phosphate cements have been widely applied in orthopaedic and dental fields because of their self-setting ability, development of high-strength bone cement with bioactivity and biodegradability remains a major challenge. Therefore, the purpose of this study is to prepare a tricalcium silicate/magnesium phosphate (C3S/MPC) composite bone cement, which is intended to combine the excellent bioactivity of C3S with remarkable self-setting properties and mechanical strength of MPC. The self-setting and mechanical properties, in vitro induction of apatite formation and degradation behaviour, and cytocompatibility of the composite cements were investigated. Our results showed that the C3S/MPC composite cement with an optimal composition had compressive strength up to 87 MPa, which was significantly higher than C3S (25 MPa) and MPC (64 MPa). The setting time could be adjusted between 3 min and 29 min with the variation of compositions. The hydraulic reaction products of the C3S/MPC composite cement were composed of calcium silicate hydrate (CSH) derived from the hydration of C3S and gel-like amorphous substance. The C3S/MPC composite cements could induce apatite mineralization on its surface in SBF solution and degraded gradually in Tris-HCl solution. Besides, the composite cements showed good cytocompatibility and stimulatory effect on the proliferation of MC3T3-E1 osteoblast cells. Our results indicated that the C3S/MPC composite bone cement might be a new promising high-strength inorganic bioactive material which may hold the potential for bone repair in load-bearing site.

  15. Pyrolytic carbon coating for cytocompatibility of titanium oxide nanoparticles: a promising candidate for medical applications.

    NARCIS (Netherlands)

    Behzadi, S.; Imani, M.; Yousefi, M.; Galinetto, P.; Simchi, A.; Amiri, H.; Stroeve, P.; Mahmoudi, M.

    2012-01-01

    Nanoparticles for biomedical use must be cytocompatible with the biological environment that they are exposed to. Current research has focused on the surface functionalization of nanoparticles by using proteins, polymers, thiols and other organic compounds. Here we show that inorganic nanoparticles

  16. Cytocompatibility and biocompatibility of nanostructured carbonated hydroxyapatite spheres for bone repair

    Science.gov (United States)

    CALASANS-MAIA, Mônica Diuana; de MELO, Bruno Raposo; ALVES, Adriana Terezinha Neves Novellino; RESENDE, Rodrigo Figueiredo de Brito; LOURO, Rafael Seabra; SARTORETTO, Suelen Cristina; GRANJEIRO, José Mauro; ALVES, Gutemberg Gomes

    2015-01-01

    ABSTRACT Objective The aim of this study was to investigate the in vitro and in vivo biological responses to nanostructured carbonated hydroxyapatite/calcium alginate (CHA) microspheres used for alveolar bone repair, compared to sintered hydroxyapatite (HA). Material and Methods The maxillary central incisors of 45 Wistar rats were extracted, and the dental sockets were filled with HA, CHA, and blood clot (control group) (n=5/period/group). After 7, 21 and 42 days, the samples of bone with the biomaterials were obtained for histological and histomorphometric analysis, and the plasma levels of RANKL and OPG were determined via immunoassay. Statistical analysis was performed by Two-Way ANOVA with post-hoc Tukey test at 95% level of significance. Results The CHA and HA microspheres were cytocompatible with both human and murine cells on an in vitro assay. Histological analysis showed the time-dependent increase of newly formed bone in control group characterized by an intense osteoblast activity. In HA and CHA groups, the presence of a slight granulation reaction around the spheres was observed after seven days, which was reduced by the 42nd day. A considerable amount of newly formed bone was observed surrounding the CHA spheres and the biomaterials particles at 42-day time point compared with HA. Histomorphometric analysis showed a significant increase of newly formed bone in CHA group compared with HA after 21 and 42 days from surgery, moreover, CHA showed almost 2-fold greater biosorption than HA at 42 days (two-way ANOVA, p<0.05) indicating greater biosorption. An increase in the RANKL/OPG ratio was observed in the CHA group on the 7th day. Conclusion CHA spheres were osteoconductive and presented earlier biosorption, inducing early increases in the levels of proteins involved in resorption. PMID:26814461

  17. Niobium-Doped Hydroxyapatite Bioceramics: Synthesis, Characterization and In Vitro Cytocompatibility

    Directory of Open Access Journals (Sweden)

    Nádia S. V. Capanema

    2015-07-01

    Full Text Available Doping calcium phosphates with ionic species can play an important role in biological responses promoting alkaline phosphatase activity, and, therefore inducing the generation of new bone. Thus, in this study, the synthesis of niobium-doped hydroxyapatite (Nb-HA nanosize particles obtained by the precipitation process in aqueous media followed by thermal treatment is presented. The bioceramics were extensively characterized by X-ray diffraction, wavelength dispersive X-ray fluorescence spectrometry, Fourier transform infrared spectroscopy, scanning electron microscopy/energy dispersive X-ray spectroscopy analysis, transmission electron microscopy, atomic force microscopy and thermal analysis regarding their chemical composition, structure and morphology. The results showed that the precipitate dried at 110 °C was composed of amorphous calcium phosphate and HA, with polidisperse particles ranging from micro to nano dimensions. After the thermal treatment at 900 °C, the bioceramic system evolved predominantly to HA crystalline phase, with evident features of particle sintering and reduction of surface area. Moreover, the addition of 10 mol% of niobium salt precursor during the synthesis indicated the complete incorporation of the Nb(V species in the HA crystals with detectable changes in the original lattice parameters. Furthermore, the incorporation of Nb ions caused a significant refinement on the average particle size of HA. Finally, the preliminary cytocompatibility response of the biomaterials was accessed by human osteoblast cell culture using MTT and resazurin assays, which demonstrated no cytotoxicity of the Nb-alloyed hydroxyapatite. Thus, these findings seem promising for developing innovative Nb-doped calcium phosphates as artificial biomaterials for potential use in bone replacements and repair.

  18. Novel naturally crosslinked electrospun nanofibrous chitosan mats for guided bone regeneration membranes: material characterization and cytocompatibility.

    Science.gov (United States)

    Norowski, Peter A; Fujiwara, Tomoko; Clem, William C; Adatrow, Pradeep C; Eckstein, Eugene C; Haggard, Warren O; Bumgardner, Joel D

    2015-05-01

    Guided bone regeneration (GBR) barrier membranes are used to prevent soft tissue infiltration into the graft space during dental procedures that involve bone grafting. Chitosan materials have shown promise as GBR barrier membranes, due to their biocompatibility and predictable biodegradability, but degradation rates may still be too high for clinical applications. In this study, chitosan GBR membranes were electrospun using chitosan (70% deacetylated, 312 kDa, 5.5 w/v%), with or without the addition of 5 or 10 mm genipin, a natural crosslinking agent, in order to extend the degradation to meet the clinical target time frame of 4-6 months. Membranes were evaluated for fibre diameter, tensile strength, biodegradation rate, bond structure and cytocompatibility. Genipin addition, at 5 or 10 mm, resulted in median fibre diameters 184, 144 and 154 nm for uncrosslinked, 5 mm and 10 mm crosslinked, respectively. Crosslinking, examined by Fourier transform infrared spectroscopy, showed a decrease in N-H stretch as genipin levels were increased. Genipin-crosslinked mats exhibited only 22% degradation based on mass loss, as compared to 34% for uncrosslinked mats at 16 weeks in vitro. The ultimate tensile strength of the mats was increased by 165% to 32 MPa with 10 mm crosslinking as compared to the uncrosslinked mats. Finally, genipin-crosslinked mats supported the proliferation of SAOS-2 cells in a 5 day growth study, similar to uncrosslinked mats. These results suggest that electrospun chitosan mats may benefit from genipin crosslinking and have the potential to meet clinical degradation time frames for GBR applications.

  19. In vitro hemocompatibility and cytocompatibility of dexamethasone-eluting PLGA stent coatings

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Jiang; Liu, Yang; Luo, Rifang; Chen, Si; Li, Xin; Yuan, Shuheng; Wang, Jin, E-mail: jinxxwang@263.net; Huang, Nan

    2015-02-15

    Highlights: • Biodegradable dexamethasone-eluting PLGA stent coatings were developed. • Stent coatings can withstand the compressive and tensile strains without cracking. • Stent coatings presented favorable release kinetic for the lesion site. • Stent coatings can effectively inhibit the adhesion and activation of platelets. • Stent coatings can effectively inhibit the proliferation of SMC. - Abstract: Drug-eluting stents (DESs) have been an important breakthrough for interventional cardiology applications since 2002. Though successful in reducing restenosis, some adverse clinical problems still emerged, which were mostly caused by the bare-metal stents and non-biodegradable polymer coatings, associated with the delayed endothelialization process. In this study, dexamethasone-loaded poly (lactic-co-glycolic acid) (PLGA) coatings were developed to explore the potential application of dexamethasone-eluting stents. Dexamethasone-eluting PLGA stents were prepared using ultrasonic atomization spray method. For other tests like stability and cytocompatibility and hemocompatibility tests, dexamethasone loaded coatings were deposited on 316L SS wafers. Fourier transform-infrared spectroscopy (FT-IR) results demonstrated that there was no chemical reaction between PLGA and dexamethasone. The balloon expansion experiment and surface morphology observation suggested that the stent coatings were smooth and uniform, and could also withstand the compressive and tensile strains imparted without cracking after stent expansion. The drug release behavior in vitro indicated that dexamethasone existed burst release within 1 day, but it presented linear release characteristics after 6 days. In vitro platelets adhesion, activation test and APTT test were also done, which showed that after blending dexamethasone into PLGA, the hemocompatibility was improved. Besides, dexamethasone and dexamethasone-loaded PLGA coatings could significantly inhibit the attachment and

  20. Synthesis, characterization, and cytocompatibility of potential cockle shell aragonite nanocrystals for osteoporosis therapy and hormonal delivery

    Directory of Open Access Journals (Sweden)

    Jaji AZ

    2017-01-01

    at pH 7.5, enabling sustained slow release of PTH 1-34 for 168 h (1 week. A 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide cytocompatibility assay in Human Foetal Osteoblast Cell Line hFOB 1.19 showed that ANC can safely support osteoblast proliferation up to 48 h whereas PTH-ANC can safely support the proliferation at 72 h and beyond due to the sustained slow release of PTH 1-34. It was concluded that due to its biogenic nature, ANC is a cytocompatible antiosteoporotic agent. It doubles as a nanocarrier for the enhancement of efficacy and safety of the bone anabolic PTH 1-34. ANC is expected to reduce the cost, dosage, and dose frequency associated with the use of PTH 1-34 management of primary and secondary forms of osteoporosis. Keywords: bone, FESEM, FT-IR, MTT viability, PTH 1-34, sustained release, TEM, XRD, zeta potential

  1. Composite bone cements loaded with a bioactive and ferrimagnetic glass-ceramic: Leaching, bioactivity and cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Verné, Enrica, E-mail: enrica.verne@polito.it [Institute of Materials Physics and Engineering, Applied Science and Technology Department, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino (Italy); Bruno, Matteo [Institute of Materials Physics and Engineering, Applied Science and Technology Department, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino (Italy); Miola, Marta [Institute of Materials Physics and Engineering, Applied Science and Technology Department, Politecnico di Torino, C. so Duca degli Abruzzi 24, 10129 Torino (Italy); Department of Health Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Via Solaroli 17, 28100 Novara (Italy); Maina, Giovanni; Bianco, Carlotta [Traumatology Orthopedics and Occupational Medicine Dept., Università di Torino, Via G. Zuretti 29, 10126 Torino (Italy); Cochis, Andrea [Department of Health Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Via Solaroli 17, 28100 Novara (Italy); Rimondini, Lia [Department of Health Sciences, Università del Piemonte Orientale “Amedeo Avogadro”, Via Solaroli 17, 28100 Novara (Italy); Consorzio Interuniversitario Nazionale per la Scienza e Tecnologia dei Materiali, Via G. Giusti, 9, 50121 Firenze (Italy)

    2015-08-01

    In this work, composite bone cements, based on a commercial polymethylmethacrylate matrix (Palamed®) loaded with ferrimagnetic bioactive glass-ceramic particles (SC45), were produced and characterized in vitro. The ferrimagnetic bioactive glass-ceramic belongs to the system SiO{sub 2}–Na{sub 2}O–CaO–P{sub 2}O{sub 5}–FeO–Fe{sub 2}O{sub 3} and contains magnetite (Fe{sub 3}O{sub 4}) crystals into a residual amorphous bioactive phase. Three different formulations (containing 10, 15 and 20 wt.% of glass-ceramic particles respectively) have been investigated. These materials are intended to be applied as bone fillers for the hyperthermic treatment of bone tumors. The morphological, compositional, calorimetric and mechanical properties of each formulation have been already discussed in a previous paper. The in vitro properties of the composite bone cements described in the present paper are related to iron ion leaching test (by graphite furnace atomic absorption spectrometer), bioactivity (i.e. the ability to stimulate the formation of a hydroxyapatite – HAp – layer on their surface after soaking in simulated body fluid SBF) and cytocompatibility toward human osteosarcoma cells (ATCC CRL-1427, Mg63). Morphological and chemical characterizations by scanning electron microscopy and energy dispersion spectrometry have been performed on the composite samples after each test. The iron release was negligible and all the tested samples showed the growth of HAp on their surface after 28 days of immersion in a simulated body fluid (SBF). Cells showed good viability, morphology, adhesion, density and the ability to develop bridge-like structures on all investigated samples. A synergistic effect between bioactivity and cell mineralization was also evidenced. - Highlights: • An in vitro biological characterization was carried out on ferromagnetic and bioactive composite cements. • No release of iron was revealed in the physiological solution. • Bioactivity tests

  2. Poly(hydroxybutyrate)/cellulose acetate blend nanofiber scaffolds: Preparation, characterization and cytocompatibility

    Energy Technology Data Exchange (ETDEWEB)

    Zhijiang, Cai, E-mail: caizhijiang@hotmail.com [School of Textiles, Tianjin Polytechnic University, Tianjin 300387 (China); State Key Laboratory of Hollow Fiber Membrane Material and Processes, No 399 BingShuiXi Street, XiQing District, Tianjin, China, 300387 (China); Yi, Xu; Haizheng, Yang; Jia, Jianru; Liu, Yuanpei [School of Textiles, Tianjin Polytechnic University, Tianjin 300387 (China)

    2016-01-01

    Poly(hydroxybutyrate) (PHB)/cellulose acetate (CA) blend nanofiber scaffolds were fabricated by electrospinning using the blends of chloroform and DMF as solvent. The blend nanofiber scaffolds were characterized by SEM, FTIR, XRD, DSC, contact angle and tensile test. The blend nanofibers exhibited cylindrical, uniform, bead-free and random orientation with the diameter ranged from 80–680 nm. The scaffolds had very well interconnected porous fibrous network structure and large aspect surface areas. It was found that the presence of CA affected the crystallization of PHB due to formation of intermolecular hydrogen bonds, which restricted the preferential orientation of PHB molecules. The DSC result showed that the PHB and CA were miscible in the blend nanofiber. An increase in the glass transition temperature was observed with increasing CA content. Additionally, the mechanical properties of blend nanofiber scaffolds were largely influenced by the weight ratio of PHB/CA. The tensile strength, yield strength and elongation at break of the blend nanofiber scaffolds increased from 3.3 ± 0.35 MPa, 2.8 ± 0.26 MPa, and 8 ± 0.77% to 5.05 ± 0.52 MPa, 4.6 ± 0.82 MPa, and 17.6 ± 1.24% by increasing PHB content from 60% to 90%, respectively. The water contact angle of blend nanofiber scaffolds decreased about 50% from 112 ± 2.1° to 60 ± 0.75°. The biodegradability was evaluated by in vitro degradation test and the results revealed that the blend nanofiber scaffolds showed much higher degradation rates than the neat PHB. The cytocompatibility of the blend nanofiber scaffolds was preliminarily evaluated by cell adhesion studies. The cells incubated with PHB/CA blend nanofiber scaffold for 48 h were capable of forming cell adhesion and proliferation. It showed much better biocompatibility than pure PHB film. Thus, the prepared PHB/CA blend nanofiber scaffolds are bioactive and may be more suitable for cell proliferation suggesting that these scaffolds can be used for

  3. PDMS-SiO{sub 2}-TiO{sub 2}-CaO hybrid materials – Cytocompatibility and nanoscale surface features

    Energy Technology Data Exchange (ETDEWEB)

    Almeida, J. Carlos [CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Wacha, András [Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok körútja 2, Budapest 1117 (Hungary); Gomes, Pedro S.; Fernandes, M. Helena R. [Laboratory for Bone Metabolism and Regeneration, Faculdade de Medicina Dentária, Universidade do Porto (Portugal); Fernandes, M. Helena Vaz [CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro (Portugal); Salvado, Isabel M. Miranda, E-mail: isabelmsalvado@ua.pt [CICECO - Aveiro Institute of Materials, Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro (Portugal)

    2016-07-01

    Two PDMS-SiO{sub 2}-TiO{sub 2}-CaO porous hybrid materials were prepared using the same base composition, precursors, and solvents, but following two different sol-gel procedures, based on the authors' previous works where for the first time, in this hybrid system, calcium acetate was used as calcium source. The two different procedures resulted in monolithic materials with different structures, microstructures, and surface wettability. Even though both are highly hydrophobic (contact angles of 127.2° and 150.6°), and present different filling regimes due to different surface topographies, they have demonstrated to be cytocompatible when tested with human osteoblastic cells, against the accepted idea that high-hydrophobic surfaces are not suitable to cell adhesion and proliferation. At the nanoscale, the existence of hydrophilic silica domains containing calcium, where water molecules are physisorbed, is assumed to support this capability, as discussed. - Highlights: • Two hybrid materials were prepared following two different sol-gel procedures. • Both are highly hydrophobic but demonstrated to be cytocompatible. • Different filling regimes were observed.

  4. Oxygen plasma surface modification augments poly(L-lactide-co-glycolide) cytocompatibility toward osteoblasts and minimizes immune activation of macrophages.

    Science.gov (United States)

    Scislowska-Czarnecka, Anna; Szmigiel, Dariusz; Genet, Michel; Dupont-Gillain, Christine; Pamula, Elzbieta; Kolaczkowska, Elzbieta

    2015-12-01

    Here, we report on modification of one of the model biomedical polymers, poly L-lactide-co-glycolide (PLGA; 85:15), by reactive ion etching (RIE) oxygen plasma treatment. PLGA's major disadvantage is high hydrophobicity which restrains binding of cell-adhesive proteins and host cells. In the current approach, we aimed to answer two questions: (1) will only short (10 s) and moderate (20-200 mTorr, 45-90 W) RIE oxygen plasma treatment, leading to decrease of water contact angle by only up to 10°, sufficiently improve PLGA adherence to cells, and (2) how will this affect osteoblasts and activation of the immune system? All obtained modified PLGAs had improved hydrophilicity but unaltered roughness (as revealed by water contact angle measurements, X-ray photoelectron spectroscopy, and atomic force microscopy) resulting in significantly improved adhesion of osteoblasts (MG-63) and their low activation. Importantly, macrophages (RAW 264.7), one of the key cells initiating inflammation and bone resorption, responded significantly less vigorously to the modified polymers, expressing/releasing lower amounts of nitric oxide, matrix metalloproteinases (MMP-9), and pro-inflammatory cytokines (TNF-α, IL-6, IL-12p70, IFN-γ, IL-10). We conclude that already slight RIE oxygen plasma modification of PLGA is sufficient to improve its surface properties, and enhance cytocompatibility. Most importantly, this type of modification prevents excessive immune response.

  5. In Vitro Assessment of Antibacterial Activity and Cytocompatibility of Quercetin-Containing PLGA Nanofibrous Scaffolds for Tissue Engineering

    Directory of Open Access Journals (Sweden)

    Zhi-Cai Xing

    2012-01-01

    Full Text Available Flavonoids, such as quercetin, have been reported to exhibit a wide range of biological activities related to their antioxidant capacity. The aim of this study was to investigate the protective effect of quercetin on cell adhesion, and the viability and proliferation of KB epithelial cells. Quercetin- (1, 5 wt%-containing poly (l-lactide-co-glycolide (PLGA nanofibrous scaffolds (PLGA/Q 1, PLGA/Q 5 were prepared by electrospinning technique and their antibacterial properties were examined. Two types of bacteria strains, Staphylococcus aureus (SA and Klebsiella pneumoniae (KP, were used to evaluate the antibacterial properties of the scaffolds. The results showed that the quercetin-containing PLGA nanofibrous scaffolds exhibited significant antibacterial effects against the two bacterial strains. KB epithelial cells were also used to evaluate the cytocompatibility of the scaffolds. From the results, it was found that the PLGA nanofibrous scaffolds with 1 wt% of quercetin had good cell compatibility. It is considered that the PLGA nanofibrous scaffolds with 1 wt% quercetin have potential to be used in tissue engineering.

  6. Improvement of bioactivity, degradability, and cytocompatibility of biocement by addition of mesoporous magnesium silicate into sodium-magnesium phosphate cement.

    Science.gov (United States)

    Wu, Yingyang; Tang, Xiaofeng; Chen, Jie; Tang, Tingting; Guo, Han; Tang, Songchao; Zhao, Liming; Ma, Xuhui; Hong, Hua; Wei, Jie

    2015-09-01

    A novel mesoporous magnesium-based cement (MBC) was fabricated by using the mixed powders of magnesium oxide, sodium dihydrogen phosphate, and mesoporous magnesium silicate (m-MS). The results indicate that the setting time and water absorption of the MBC increased as a function of increasing m-MS content, while compressive strength decreased. In addition, the degradability of the MBC in a solution of Tris-HCl and the ability of apatite formation on the MBC were significantly improved with the increase in m-MS content. In cell culture experiments, the results show that the attachment, proliferation, and alkaline phosphatase activity of the MC3T3-E1 cells on the MBC were significantly enhanced with the increase of the content of m-MS. It can be suggested that the MBC with good cytocompatibility could promote the proliferation and differentiation of the MC3T3-E1 cells. In short, our findings indicate that the MBC containing m-MS had promising potential as a new biocement for bone regeneration and repair applications.

  7. Chemo-Enzymatic Synthesis of Perfluoroalkyl-Functionalized Dendronized Polymers as Cyto-Compatible Nanocarriers for Drug Delivery Applications

    Directory of Open Access Journals (Sweden)

    Badri Parshad

    2016-08-01

    Full Text Available Among amphiphilic polymers with diverse skeletons, fluorinated architectures have attracted significant attention due to their unique property of segregation and self-assembly into discrete supramolecular entities. Herein, we have synthesized amphiphilic copolymers by grafting hydrophobic alkyl/perfluoroalkyl chains and hydrophilic polyglycerol [G2.0] dendrons onto a co-polymer scaffold, which itself was prepared by enzymatic polymerization of poly[ethylene glycol bis(carboxymethyl ether]diethylester and 2-azidopropan-1,3-diol. The resulting fluorinated polymers and their alkyl chain analogs were then compared in terms of their supramolecular aggregation behavior, solubilization capacity, transport potential, and release profile using curcumin and dexamethasone drugs. The study of the release profile of encapsulated curcumin incubated with/without a hydrolase enzyme Candida antarctica lipase (CAL-B suggested that the drug is better stabilized in perfluoroalkyl chain grafted polymeric nanostructures in the absence of enzyme for up to 12 days as compared to its alkyl chain analogs. Although both the fluorinated as well as non-fluorinated systems showed up to 90% release of curcumin in 12 days when incubated with lipase, a comparatively faster release was observed in the fluorinated polymers. Cell viability of HeLa cells up to 95% in aqueous solution of fluorinated polymers (100 μg/mL demonstrated their excellent cyto-compatibility.

  8. Influence of modified polyester on the material properties of collagen-based biocomposites and in vitro evaluation of cytocompatibility.

    Science.gov (United States)

    Wu, Chin-San

    2015-03-01

    The cytocompatibility of composite materials collagen (Col)/poly(hydroxyalkanoate) (PHA) and collagen/maleic anhydride-grafted PHA (PHA-g-MA) was investigated in this study. Col was homogeneously dispersed in the PHA-g-MA matrix as a result of condensation reactions. Mechanical characterisation indicated that the improved adhesion between Col and PHA-g-MA enhanced the tensile strength of the composite compared with that of PHA/Col. PHA-g-MA/Col composites were also more water-resistant than PHA/Col composites. Collagen and cell proliferation analysis indicated that PHA and PHA-g-MA and their composites were biocompatible with respect to FB proliferation. Cell-cycle and apoptosis assays by FBs on the PHA series composite samples were not affected by DNA content related to damage, i.e. rapid apoptosis/necrosis was not observed, demonstrating the potential of PHA/Col or PHA-g-MA/Col membranes for biomedical material applications.

  9. Characterization and in vitro cytocompatibility of piezoelectric electrospun scaffolds.

    Science.gov (United States)

    Weber, N; Lee, Y-S; Shanmugasundaram, S; Jaffe, M; Arinzeh, T L

    2010-09-01

    Previous studies have shown that electrical charges influence cell behavior (e.g. enhancement of nerve regeneration, cell adhesion, cell morphology). Thus, piezoelectric scaffolds might be useful for various tissue engineering applications. Fibrous scaffolds were successfully fabricated from permanent piezoelectric poly(vinylidene fluoride-trifluoroethylene) (PVDF-TrFE) by the electrospinning technique. Scanning electron microscopy and capillary flow analyses verified that the fiber mats had an average fiber diameter of 970 +/- 480 nm and a mean pore diameter of 1.7 microm, respectively. Thermally stimulated depolarization current spectroscopy measurements confirmed the piezoelectric property of the PVDF-TrFE fibrous scaffolds by the generation of a spontaneous current with the increase in temperature in the absence of an electric field, which was not detected in the unprocessed PVDF-TrFE powder. Differential scanning calorimetry, thermogravimetric analysis, X-ray diffraction and Fourier transform infrared spectroscopy results showed that the electrospinning process increased the crystallinity and presence of the polar, beta-phase crystal compared with the unprocessed powder. Confocal fluorescence microscopy and a cell proliferation assay demonstrated spreading and increased cell numbers (human skin fibroblasts) over time on PVDF-TrFE scaffolds, which was comparable with tissue culture polystyrene. The relative quantity of gene expression for focal adhesion proteins (measured by real-time RT-PCR) increased in the following order: paxillin PVDF-TrFE scaffolds in the field of regenerative medicine.

  10. In vitro degradation and cytocompatibility of dicalcium phosphate dihydrate cements prepared using the monocalcium phosphate monohydrate/hydroxyapatite system reveals rapid conversion to HA as a key mechanism.

    Science.gov (United States)

    Alge, Daniel L; Goebel, W Scott; Chu, Tien-Min Gabriel

    2012-04-01

    We previously showed that dicalcium phosphate dihydrate (DCPD) cements can be prepared using monocalcium phosphate monohydrate (MCPM) and hydroxyapatite (HA). In this study, we have characterized the degradation properties and biocompatibility of these novel cements. To study the degradation properties, cements were prepared using MCPM:HA molar ratios of 4:1, 2:1, 2:3, and 2:5. Degradation was evaluated in vitro by static soaking in PBS, and changes in pH, mass, compressive strength, and composition were monitored. Conversion of DCPD to HA was noted in the 4:1 group, which initially consisted of pure DCPD. However, the 2:1 group, which initially consisted of DCPD and an intermediate amount of unreacted HA, underwent rapid conversion to HA associated with significantly greater pH drop and mass loss as well as a complete loss of mechanical integrity. On the basis of these results, we directly compared the cytocompatibility of 2:1 MCPM:HA cements to DCPD cements prepared with an equivalent percent molar excess of β-tricalcium phosphate (β-TCP) using an in vitro cell viability assay. Viability of cells co-cultured with 2:1 MCPM:HA cements was significantly reduced after just 48 h, while viability of cells cultured with the β-TCP-based cements was no different from control cells. In conclusion, this study demonstrates that conversion to HA plays an important role in the degradation of DCPD cements prepared with the MCPM/HA system, affecting both physical properties and cytocompatibility. These results could have important clinical implications for MCPM/HA cements.

  11. Nanostructured titanium-silver coatings with good antibacterial activity and cytocompatibility fabricated by one-step magnetron sputtering

    Science.gov (United States)

    Bai, Long; Hang, Ruiqiang; Gao, Ang; Zhang, Xiangyu; Huang, Xiaobo; Wang, Yueyue; Tang, Bin; Zhao, Lingzhou; Chu, Paul K.

    2015-11-01

    Bacterial infection and loosing are serious complications for biomedical implants in the orthopedic, dental, and other biomedical fields and the ideal implants should combine good antibacterial ability and bioactivity. In this study, nanostructured titanium-silver (Ti-Ag) coatings with different Ag contents (1.2 to 21.6 at%) are prepared on Ti substrates by magnetron sputtering. As the Ag concentration is increased, the coatings change from having dense columnar crystals to sparse ones and eventually no columnar structure. The Ti-Ag coatings can effectively kill Staphylococcus aureus during the first few days and remain moderately antibacterial after immersion for 75 days. Compared to pure Ti, the Ti-Ag coatings show good cytocompatibility as indicated by good osteoblast adhesion, proliferation, intracellular total protein synthesis, and alkaline phosphatase (ALP) activity. In addition, cell spreading, collagen secretion, and extracellular matrix mineralization are promoted on the coatings with the proper Ag contents due to the nanostructured morphological features. Our results indicate that favorable antibacterial activity and osseointegration ability can be simultaneously achieved by regulating the Ag contents in Ti-Ag coatings.

  12. Cross-linked, biodegradable, cytocompatible salicylic acid based polyesters for localized, sustained delivery of salicylic acid: an in vitro study.

    Science.gov (United States)

    Chandorkar, Yashoda; Bhagat, Rajesh K; Madras, Giridhar; Basu, Bikramjit

    2014-03-10

    In order to suppress chronic inflammation while supporting cell proliferation, there has been a continuous surge toward development of polymers with the intention of delivering anti-inflammatory molecules in a sustained manner. In the above backdrop, we report the synthesis of a novel, stable, cross-linked polyester with salicylic acid (SA) incorporated in the polymeric backbone and propose a simple synthesis route by melt condensation. The as-synthesized polymer was hydrophobic with a glass transition temperature of 1 °C, which increases to 17 °C upon curing. The combination of NMR and FT-IR spectral techniques established the ester linkages in the as-synthesized SA-based polyester. The pH-dependent degradation rate and the rate of release of salicylic acid from the as-synthesized SA-based polymer were studied at physiological conditions in vitro. The polyester underwent surface erosion and exhibited linear degradation kinetics in which a change in degradation rate is observed after 4-10 days and 24% mass loss was recorded after 4 months at 37 °C and pH 7.4. The delivery of salicylic acid also showed a similar change in slopes, with a sustained release rate of 3.5% in 4 months. The cytocompatibility studies of these polyesters were carried out with C2C12 murine myoblast cells using techniques like MTT assay and flow cytometry. Our results strongly suggest that SA-based polyester supports cell proliferation for 3 days in culture and do not cause cell death (salicylic acid and have applications in adjuvant cancer therapy, chronic wound healing, and as an alternative to commercially available polymers like poly(lactic acid) and poly(glycolic acid) or their copolymers.

  13. Cytocompatible antifungal acrylic resin containing silver nanoparticles for dentures

    Directory of Open Access Journals (Sweden)

    Acosta-Torres LS

    2012-09-01

    Full Text Available Laura Susana Acosta-Torres,1 Irasema Mendieta,2 Rosa Elvira Nuñez-Anita,3 Marcos Cajero-Juárez,3 Víctor M Castaño41National School of Higher Education, School of Dentistry - Leon Unit, National Autonomus University of Mexico (UNAM, Leon, Guanajuato, 2Neurobiology Institute, National Autonomus University of Mexico (UNAM, Juriquilla, Queretaro, 3Animal Biotechnology Laboratory, Faculty of Veterinary Medicine at San Nicolas de Hidalgo, Michoacán University, Michoacán, 4Molecular Materials Department, Applied Physics and Advanced Technology Center, National Autonomus University of Mexico (UNAM, Juriquilla, Queretaro, MexicoBackground: Inhibition of Candida albicans on denture resins could play a significant role in preventing the development of denture stomatitis. The safety of a new dental material with antifungal properties was analyzed in this work.Methods: Poly(methyl methacrylate [PMMA] discs and PMMA-silver nanoparticle discs were formulated, with the commercial acrylic resin, Nature-CrylTM, used as a control. Silver nanoparticles were synthesized and characterized by ultraviolet-visible spectroscopy, dispersive Raman spectroscopy, and transmission electron microscopy. The antifungal effect was assessed using a luminescent microbial cell viability assay. Biocompatibility tests were carried out using NIH-3T3 mouse embryonic fibroblasts and a Jurkat human lymphocyte cell line. Cells were cultured for 24 or 72 hours in the presence or absence of the polymer formulations and analyzed using three different tests, ie, cellular viability by 3-(4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide (MTT assay, and cell proliferation by enzyme-linked immunosorbent assay BrdU, and genomic DNA damage (Comet assay. Finally, the samples were evaluated mechanically, and the polymer-bearing silver nanoparticles were analyzed microscopically to evaluate dispersion of the nanoparticles.Results: The results show that PMMA-silver nanoparticle discs

  14. Cytocompatibility and early osseointegration of nanoTiO{sub 2}-modified Ti-24 Nb-4 Zr-7.9 Sn surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Liu, X.H. [Department of Prosthodontics, China Medical University School of Stomatology, Shenyang (China); Wu, L., E-mail: wulin13@163.com [Department of Prosthodontics, China Medical University School of Stomatology, Shenyang (China); Ai, H.J. [Department of Prosthodontics, China Medical University School of Stomatology, Shenyang (China); Han, Y. [State Key laboratory for Mechanical Behaviour of Materials, Xi' an Jiaotong University, Xi' an (China); Hu, Y. [Department of Prosthodontics, China Medical University School of Stomatology, Shenyang (China)

    2015-03-01

    This study aimed to evaluate the cytocompatibility and early osseointegration of Ti-24 Nb-4 Zr-7.9 Sn (Ti-2448) surfaces that were modified with a nanoscale TiO{sub 2} coating. The coating was fabricated using a hydrothermal synthesis method to generate nanoTiO{sub 2}/Ti-2448. The surface characteristics of the samples were evaluated using scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and X-ray diffraction (XRD). The cytotoxicity of the fabricated nanoTiO{sub 2}/Ti-2448 was determined using MTT assays. The proliferation and alkaline phosphatase (ALP) activity of MC3T3-E1 osteoblasts cultured on nanoTiO{sub 2}/Ti-2448 were compared with those cultured on Ti-2448. Disk-shaped implants were placed in Wistar rats. The histological sections were stained with haematoxylin and eosin (HE), and the histocompatibility was analysed at 4 and 12 weeks post-implantation. Cylindrical implants were embedded in Japanese white rabbits, and the histological sections were stained with HE and anti-TGF-β1 to evaluate the histocompatibility and early osseointegration at 4, 12 and 26 weeks post-implantation. NanoTiO{sub 2}/Ti-2448 exhibited a rougher surface than did Ti-2448. NanoTiO{sub 2}/Ti-2448 was determined to be non-cytotoxic. More osteoblasts and higher ALP activity were observed for nanoTiO{sub 2}/Ti-2448 than Ti-2448 (p < 0.05). Few inflammatory cells were detected around nanoTiO{sub 2}/Ti-2448, and the expression of TGF-β1 on nanoTiO{sub 2}/Ti-2448 peaked at earlier time than that on Ti-2448. The results indicate that the cytocompatibility and early osseointegration were enhanced by the nanoTiO{sub 2} coating. - Highlights: • The cytocompatibility of nanoTiO2/Ti-2448 is first reported in our work. • The early osseointegration of nanoTiO2/Ti-2448 is first reported in our work. • We evaluate the biocompatibility of nanoTiO2/Ti-2448 by in-vitro and in-vivo tests.

  15. Hemocompatibility and cytocompatibility of the hirudin-modified silk fibroin.

    Science.gov (United States)

    Sun, Dan; Hao, Yunxia; Yang, Gaoqiang; Wang, Jiannan

    2015-04-01

    Hirudin (Hir), a thrombin direct inhibitor, was used to modify a polyethylene glycol diglycidyl ether (PEG-DE) crosslinked regenerated silk fibroin (SF) material to improve hemocompatibility. Hemolysis characteristics, platelet adhesion, platelet activity, and plasma recalcification time were investigated using absorption spectrometry, scanning electron microscopy, MTT analysis, and the time counting method. Hirudin could be grafted evenly to the silk fibroin, and the modified material was resistant to hemolysis at ratios of less than 0.5%. Scanning electron microscopy and MTT results showed that platelet adhesion and aggregation activity decreased after modificaton with trace amounts of hirudin, compared with PEG-DE crosslinked and ethanol-treated silk fibroin film. Plasma recalcification of PEG-DE crosslinked silk fibroin film was slower than with ethanol-treated material, and this increased slightly after hirudin modification. Furthermore, L929, HAVSMC, and HUVEC cells adhered to the modified material, grew well, and possessed high proliferation activity on SF/Hir blend films. This study suggests that hirudin could improve the anticoagulation properties of regenerated silk fibroin materials.

  16. In vitro degradation, hemolysis, and cytocompatibility of PEO/PLLA composite coating on biodegradable AZ31 alloy.

    Science.gov (United States)

    Wei, Zhongling; Tian, Peng; Liu, Xuanyong; Zhou, Bangxin

    2015-02-01

    Magnesium and its alloys have large potential as degradable and absorbable biomaterials because of their mechanical properties and biocompatibility. However, their corrosion resistance is usually inadequate especially in physiological environment, which limits their broad applications in biomedical areas. In this work, plasma electrolytic oxidized/poly(l-lactide) (PEO/PLLA) composite coating was successfully fabricated on biodegradable AZ31 alloy by combing PEO process and sealing with PLLA. The microstructure, elemental composition, and phase composition of the PEO/PLLA composite coating were investigated. The in vitro degradation of the PEO/PLLA composite coating in simulated body fluid (SBF) was also systematically evaluated. The results revealed that the PEO/PLLA composite coating improved the corrosion resistance of AZ31 alloy significantly. The corrosion potential shifted from -1.663V to more positive position -1.317 V and the corrosion current density was reduced with six-order of magnitude. The Mg(2+) ions, hydrogen release, and pH value change of solution caused by degradation were all decreased significantly. Moreover, the PEO process played a critical role in sustaining the integrity of the implant in long-term service. The result of hemolysis test showed that the PEO/PLLA composite coating vested AZ31 alloy a low hemolysis ratio (0.806 ± 0.771)%, which is much lower than the safe value of 5% according to ISO 10993-4. For the cytocompatibility test, compared with bare AZ31 alloy and PEO coating, MC3T3-E1 cells showed much better adhesion and proliferation on the PEO/PLLA composite coating with nearly 4-fold increase of cells after 7-day cultivation, indicating that the PEO/PLLA composite coating has good biocompatibility for biomedical applications.

  17. Formation mechanism, degradation behavior, and cytocompatibility of a nanorod-shaped HA and pore-sealed MgO bilayer coating on magnesium.

    Science.gov (United States)

    Li, Bo; Han, Yong; Qi, Kai

    2014-10-22

    A novel bilayer coating (HT24h) was fabricated on magnesium using microarc oxidation (MAO) and hydrothermal treatment (HT). The coating comprises an outer layer of narrow interrod spaced hydroxyapatite (HA) nanorods and an inner layer of MgO containing Mg(OH)2/HA-sealing-pores. The hydrothermal formation mechanism of HA nanorods on MAO-formed MgO was explored. Also, evolution of structure and bonding integrity of HT24h coating with immersion in physiological saline (PS) for 0-90 days, corrosion resistance and cytocompatibility of the coating were investigated, together with MgO containing Mg(OH)2-sealing-pores (HT2h) and porous MgO (MAO) coatings. Corrosion resistance was identified by three-point bending and electrochemical tests in PS, while cytocompatibility was determined by MTT, live/dead staining, and vinculin-actin-nucleus tricolor staining assays of hFOB1.19 cells. Immersion tests indicate that cracking rather than delamination is a common feature in most areas of the coatings up to day 90 and degradation is the reason for thinning in thickness of the coatings. MAO and HT2h coatings exhibit a significant thinning due to fast degradation of MgO. However, HT24h coating shows a quite small thinning, owing to the fact that the HA nanorods underwent quite slow degradation while the underlying MgO only underwent conversion to Mg(OH)2 without dissolution of the Mg(OH)2. Scratch tests reveal that HT24h coating still retains relatively high bonding integrity, although the failure position changes from the MgO interior to a point between the HA and MgO layers after 90 days of immersion. HT24h coating appears far more effective than MAO and HT2h coatings in reducing degradation and maintaining the mechanical integrity of Mg, as well as enhancing the mitochondrial activity, adhesion, and proliferation of osteoblasts.

  18. Modulation, functionality, and cytocompatibility of three-dimensional printing materials made from chitosan-based polysaccharide composites.

    Science.gov (United States)

    Wu, Chin-San

    2016-12-01

    The mechanical properties, cytocompatibility, and fabrication of three-dimensional (3D) printing strips of composite materials containing polylactide (PLA) and chitosan (CS) were evaluated. Maleic anhydride-grafted polylactide (PLA-g-MA) and CS were used to enhance the desired characteristics of these composites. The PLA-g-MA/CS materials exhibited better mechanical properties than the PLA/CS composites; this effect was attributed to a greater compatibility between the grafted polyester and CS. The water resistance of the PLA-g-MA/CS composites was greater than that of the PLA/CS composites; cytocompatibility evaluation with human foreskin fibroblasts (FBs) indicated that both materials were nontoxic. Moreover, CS enhanced the antibacterial activity properties of PLA-g-MA and PLA/CS composites.

  19. Synthesis, characterization and cytocompatibility of a poly(diol-tricarballylate) visible light photo-cross-linked biodegradable elastomer.

    Science.gov (United States)

    Shaker, Mohamed A; Doré, Jules J E; Younes, Husam M

    2010-01-01

    The synthesis, characterization and in vitro cytocompatibility of a new family of photo-cross-linked amorphous poly(diol-tricarballylate) (PDT) biodegradable elastomeric polyesters are reported. The synthesis was based on the polycondensation reaction between tricarballylic acid and alkylene diols, followed by acrylation. The prepared and acrylated poly(diol-tricarballylate) (APDT) was characterized by means of FT-IR, (1)H-NMR, GPC and DSC. Liquid-to-solid photo-curing was carried out by exposing the APDT to visible light in the presence of camphorquinone as a photoinitiator. The thermal properties, mechanical characteristics, sol content, long-term in vitro degradation and cytocompatibility of the prepared PDT elastomers were also reported. The mechanical and degradation properties of this new photocurable elastomer can be precisely controlled by varying the density of acrylate moieties in the matrix of the polymer, and through changes in the pre-polymer chain length. The use of visible light cross-linking, possibility of solventless drug loading, controllable mechanical properties and cytocompatibility of these new elastomers make them excellent candidates for use in controlled implantable drug-delivery systems of protein drugs and other biomedical applications.

  20. Enhanced mechanical properties and cytocompatibility of electrospun poly(L-lactide) composite fiber membranes assisted by polydopamine-coated halloysite nanotubes

    Science.gov (United States)

    Luo, Chuang; Zou, Ziping; Luo, Binghong; Wen, Wei; Li, Huihua; Liu, Mingxian; Zhou, Changren

    2016-04-01

    To improve the dispersion and interfacial interaction between halloysite nanotubes (HNTs) and poly(L-lactide) (PLLA) matrix, and hence to increase the mechanical properties and cytocompatibility of the HNTs/PLLA composite, a facile approach was developed to prepare polydopamine-coated HNTs (D-HNTs) by the self-polymerization of dopamine (DOPA), and then HNTs and D-HNTs were further introduced into PLLA matrix to fabricate HNTs/PLLA and D-HNTs/PLLA fiber membranes based on electrospinning technique. The successful immobilization of the polydopamine (PDOPA) coating on the surfaces of HNTs was confirmed, and such PDOPA coating played an important role in improving the interfacial interaction between the nanotubes and PLLA matrix. The D-HNTs were dispersed in the matrix more uniformly than untreated HNTs, and relative smooth and uniform fiber were obtained for the D-HNTs/PLLA fiber membrane. As a result, the tensile strength and modulus of the D-HNTs/PLLA fiber membrane were obviously superior to those of the HNTs/PLLA fiber membrane. Cell culture results revealed that D-HNTs/PLLA fiber membrane was more effectively to promote MC3T3-E1 cells adhesion and proliferation than neat PLLA and HNTs/PLLA fiber membrane.

  1. Cytocompatibility of chitosan -based thermosensitive hydrogel to human periodontal ligament cell

    Institute of Scientific and Technical Information of China (English)

    PAN Jian-feng; Ji Qiu-xia; Lv Bing-hua; Li Chang-chun; Wu Hong; Li Dan-dan; Li-Hui

    2015-01-01

    Objective:To investigate the ef ect of thermosensitive chitosan /β-glycerophosphate (CS /β-GP)hydrogel on proliferation of human periodontal ligament cel s (HPDLCs). Methods:CS /β-GP were prepared into a thermosensitive hydrogel and its three -dimensional structure was observed under electron microscope.HPDLCs harvested and cultured in vitro were co -cultured with the thermosensitive CS /β-GP hydrogel.Growth of the cel s in the hydrogel was observed with HE staining,and the ef ect of the extract on proliferation of HPDLCs was exam-ined by CCK -8 assay.Results:Observations of SEMand HE staining showed that the thermosensitive CS /β-GP hydrogel was large in pore size and appropriate for cel growth.Dif erent levels of CS /α,β-GP extracts could promote proliferation of HPDLCs.Conclusion:Thermosensitive CS /β-GP hydrogel can promote proliferation of HPDLCs and be a good carrier for periodontal tis-sue engineering because of its thermosensitivity.

  2. Cytocompatibility of direct water synthesized cadmium selenide quantum dots in colo-205 cells

    OpenAIRE

    Rodriguez-Torres, Marcos R.; Velez, Christian; Zayas, Beatriz; Rivera, Osvaldo; Arslan, Zikri; Gonzalez-Vega, Maxine N.; Diaz-Diestra, Daysi; Beltran-Huarac, Juan; Morell, Gerardo; Primera-Pedrozo, Oliva M.

    2015-01-01

    Cadmium selenide quantum dots (CdSe QDs), inorganic semiconducting nanocrystals, are alluring increased attraction due to their highly refined chemistry, availability, and super tunable optical properties suitable for many applications in different research areas, such as photovoltaics, light-emitting devices, environmental sciences, and nanomedicine. Specifically, they are being widely used in bio-imaging in contrast to organic dyes due to their high brightness and improved photo-stability, ...

  3. Antimicrobial activity and cytocompatibility of silver nanoparticles coated catheters via a biomimetic surface functionalization strategy

    Directory of Open Access Journals (Sweden)

    Wu K

    2015-12-01

    Full Text Available Ke Wu,1 Yun Yang,2,3 Yanmei Zhang,2,3 Jiexi Deng,1 Changjian Lin2,31Department of Cardiology, The Affiliated Dongnan Hospital of Xiamen University, Zhangzhou, 2Department of Medical Materials, Beijing Medical Implant Engineering Research Center, Beijing Naton Technology Group, Beijing, 3State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, People’s Republic of ChinaAbstract: Catheter-related bloodstream infections are a significant problem in the clinic and may result in a serious infection. Here, we developed a facile and green procedure for buildup of silver nanoparticles (AgNPs on the central venous catheters (CVCs surface. Inspired by mussel adhesive proteins, dopamine was used to form a thin polydopamine layer and induce AgNPs formation without additional reductants or stabilizers. The chemical and physicochemical properties of AgNPs coated CVCs were characterized by scanning electron microscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, and water contact angle. The Staphylococcus aureus culture experiment was used to study the antibacterial properties. The cytocompatibility was assessed by water soluble tetrazolium salts (WST-1 assay, fluorescence staining, and scanning electron microscopy analysis. The results indicated that the CVCs surface was successfully coated with compact AgNPs. AgNPs were significantly well separated and spherical with a size of 30–50 nm. The density of AgNPs could be modulated by the concentration of silver nitrate solution. The antibacterial activity was dependent on the AgNPs dose. The high dose of AgNPs showed excellent antibacterial activity while associated with increased cytotoxicity. The appropriate density of AgNPs coated CVCs could exhibit improved biocompatibility and maintained evident sterilization effect. It is promising to design mussel-inspired silver releasing CVCs with both

  4. PLGA/DPPC/trimethylchitosan spray-dried microparticles for the nasal delivery of ropinirole hydrochloride: in vitro, ex vivo and cytocompatibility assessment

    Energy Technology Data Exchange (ETDEWEB)

    Karavasili, Christina [Laboratory of Pharmaceutical Technology, Department of Pharmacy, Aristotle University of Thessaloniki, 54124 (Greece); Bouropoulos, Nikolaos [Department of Materials Science, University of Patras, 26504 Rio, Patras (Greece); Foundation for Research and Technology, Hellas-Institute of Chemical Engineering and High Temperature, P.O. Box 1414, 26504 Patras (Greece); Sygellou, Lamprini [Foundation for Research and Technology, Hellas-Institute of Chemical Engineering and High Temperature, P.O. Box 1414, 26504 Patras (Greece); Amanatiadou, Elsa P.; Vizirianakis, Ioannis S. [Laboratory of Pharmacology, Department of Pharmaceutical Sciences, Aristotle University of Thessaloniki, GR-54124 Thessaloniki (Greece); Fatouros, Dimitrios G., E-mail: dfatouro@pharm.auth.gr [Laboratory of Pharmaceutical Technology, Department of Pharmacy, Aristotle University of Thessaloniki, 54124 (Greece)

    2016-02-01

    In the present study we investigated polymer-lipid microparticles loaded with ropinirole hydrochloride (RH) for nasal delivery. RH microparticles were further evaluated by means of scanning electron microscopy (SEM), ζ-potential measurements, Fourier-transform infrared spectroscopy (FT-IR), X-ray photoelectron spectroscopy (XPS) and x-ray diffraction (XRD). In vitro release studies were performed in simulated nasal electrolyte solution (SNES) pH 5.5 at 35 °C. Ex vivo permeation studies were conducted across sheep nasal mucosa. Cytocompatibility was tested in cultured human airway epithelial cells (Calu-3). SEM studies revealed spheroid microparticles in the range of 2.09 μm to 2.41 μm. The presence of trimethylchitosan (TMC) induced a slight shift towards less negative ζ-potential values. Surface chemistry (XPS) revealed the presence of dipalmitoylphospatidylcholine (DPPC) and poly(lactic-co-glycolic acid) (PLGA) onto microparticles' surface, further corroborating the FT-IR and XRD findings. In vitro release studies showed that the microparticle composition can partly modulate the release of RH. Ex vivo studies demonstrated a 2.35-folded enhancement of RH permeation when RH was co-formulated with TMC of low molecular weight, compared to the control. All formulations tested were found to be non-toxic to cells. The results suggest that polymer-lipid microparticles may be a promising carrier for the nasal delivery of RH. - Highlights: • Development of microparticles comprising PLGA/DPPC/TMC for nasal drug delivery. • Physicochemical characterization showed that DPPC dominated microparticles' surface. • Microparticles enhanced permeation of ropinirole across sheep nasal epithelium. • The cytotoxicity assay with Calu-3 cells demonstrated satisfactory cell viability.

  5. Cytocompatibility, mechanical and dissolution properties of high strength boron and iron oxide phosphate glass fibre reinforced bioresorbable composites.

    Science.gov (United States)

    Sharmin, Nusrat; Hasan, Muhammad S; Parsons, Andrew J; Rudd, Chris D; Ahmed, Ifty

    2016-06-01

    In this study, Polylactic acid (PLA)/phosphate glass fibres (PGF) composites were prepared by compression moulding. Fibres produced from phosphate based glasses P2O5-CaO-MgO-Na2O (P45B0), P2O5-CaO-MgO-Na2O-B2O3 (P45B5), P2O5-CaO-MgO-Na2O-Fe2O3 (P45Fe3) and P2O5-CaO-MgO-Na2O-B2O3-Fe2O3 (P45B5Fe3) were used to reinforce the bioresorbable polymer PLA. Fibre mechanical properties and degradation rate were investigated, along with the mechanical properties, degradation and cytocompatibility of the composites. Retention of the mechanical properties of the composites was evaluated during degradation in PBS at 37°C for four weeks. The fibre volume fraction in the composite varied from 19 to 23%. The flexural strength values (ranging from 131 to 184MPa) and modulus values (ranging from 9.95 to 12.29GPa) obtained for the composites matched those of cortical bone. The highest flexural strength (184MPa) and modulus (12.29GPa) were observed for the P45B5Fe3 composite. After 28 days of immersion in PBS at 37°C, ~35% of the strength profile was maintained for P45B0 and P45B5 composites, while for P45Fe3 and P45B5Fe3 composites ~40% of the initial strength was maintained. However, the overall wet mass change of P45Fe3 and P45B5Fe3 remained significantly lower than that of the P45B0 and P45B5 composites. The pH profile also revealed that the P45B0 and P45B5 composites degraded quicker, correlating well with the degradation profile. From SEM analysis, it could be seen that after 28 days of degradation, the fibres in the fractured surface of P45B5Fe3 composites remain fairly intact as compared to the other formulations. The in vitro cell culture studies using MG63 cell lines revealed both P45Fe3 and P45B5Fe3 composites maintained and showed higher cell viability as compared to the P45B0 and P45B5 composites. This was attributed to the slower degradation rate of the fibres in P45Fe3 and P45B5Fe3 composites as compared with the fibres in P45B0 and P45B5 composites.

  6. Antimicrobial Efficacy and Cytocompatibility of Calcium Hypochlorite Solution as a Root Canal Irrigant: An in Vitro Investigation

    Science.gov (United States)

    Sedigh-Shams, Mahdi; Gholami, Ahmad; Abbaszadegan, Abbas; Yazdanparast, Roohollah; Saberi Nejad, Milad; Safari, Azam; Nabavizadeh, Mohammadreza; Ghasemi, Younes

    2016-01-01

    Introduction: The purpose of this study was to compare the antimicrobial efficacy of sodium hypochlorite (SH) and calcium hypochlorite (CH) against Enterococcus faecalis (E. faecalis) using quantitative real-time polymerase chain reaction (qPCR) analysis and also to compare their cytocompatibility on L929 murine fibroblasts using Mossman’s tetrazolium toxicity (MTT) assay. Methods and Materials: A broth micro-dilution susceptibility test was used to determine the minimum inhibitory concentration (MIC) of each irrigant against E. faecalis. Then, the root canals of 50 mature extracted human mandibular premolars were contaminated with E. faecalis and were randomly divided into three groups according to the irrigant used (n=20). Canals were irrigated with SH in group I (n=20) and CH in group II (n=20) at their obtained MIC. In group III (n=10), sterile saline was used. Microbial sampling was performed before and after biomechanical preparation. Quantitative PCR was used to quantify E. faecalis in the root canal samples. For cytocompatibility assessment, L929 murine fibroblasts were exposed to various concentrations of the irrigants. Results: Irrigation with test materials resulted in significant reduction in colony forming units (CFU) in post-instrumentation samples (with the MIC values of SH and CH against E. faecalis being 0.5% and 5%, respectively). However, the reduction in the normal saline group was not significant (P=0.203). In addition, 5% CH was more effective than 0.5% SH (P=0.006) in eliminating E. faecalis. Among the different concentrations of tested irrigants, 0.5% CH and 5% SH showed the least and the most cytotoxicity, respectively (Pfaecalis in planktonic state and also its biofilm and exhibited comparable cytocompatibility to that of 0.5% SH. PMID:27471525

  7. In Vitro Corrosion and Cytocompatibility Properties of Nano-Whisker Hydroxyapatite Coating on Magnesium Alloy for Bone Tissue Engineering Applications

    Directory of Open Access Journals (Sweden)

    Huawei Yang

    2015-03-01

    Full Text Available We report here the successful fabrication of nano-whisker hydroxyapatite (nHA coatings on Mg alloy by using a simple one-step hydrothermal process in aqueous solution. The nHA coating shows uniform structure and high crystallinity. Results indicate that nHA coating is promising for improving the in vitro corrosion and cytocompatibility properties of Mg-based implants and devices for bone tissue engineering. In addition, the simple hydrothermal deposition method used in the current study is also applicable to substrates with complex shapes or surface geometries.

  8. Highly luminescent and cytocompatible cationic Ag2S NIR-emitting quantum dots for optical imaging and gene transfection

    OpenAIRE

    Duman, Fatma Demir; Hocaoğlu, İbrahim; Hocaoglu, Ibrahim; Öztürk, Deniz Gülfem; Ozturk, Deniz Gulfem; Gözüaçık, Devrim; Gozuacik, Devrim; Kiraz, Alper; Yağcı Acar, Havva; Yagci Acar, Havva

    2015-01-01

    Nanoscale PAPER Cite this: Nanoscale, 2015, 7, 11352 Received 12th January 2015, Accepted 23rd May 2015 DOI: 10.1039/c5nr00189g www.rsc.org/nanoscale Highly luminescent and cytocompatible cationic Ag2S NIR-emitting quantum dots for optical imaging and gene transfection† Fatma Demir Duman,a Ibrahim Hocaoglu,a Deniz Gulfem Ozturk,b Devrim Gozuacik,b Alper Kiraza,c and Havva Yagci Acar*a,d,e The development of non-toxic theranostic nanoparticles capable of del...

  9. Enhanced mechanical properties and cytocompatibility of electrospun poly(L-lactide) composite fiber membranes assisted by polydopamine-coated halloysite nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Chuang; Zou, Ziping [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Luo, Binghong, E-mail: tluobh@jnu.edu.cn [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Wen, Wei [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Li, Huihua [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Liu, Mingxian [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China); Zhou, Changren, E-mail: tcrz9@jnu.edu.cn [Biomaterial Research Laboratory, Department of Material Science and Engineering, College of Science and Engineering, Jinan University, Guangzhou 510632 (China); Engineering Research Center of Artificial Organs and Materials, Ministry of Education, Guangzhou 510632 (China)

    2016-04-30

    Graphical abstract: - Highlights: • D-HNTs was prepared by a facile approach based on the self-polymerization of DOPA. • The D-HNTs can disperse more uniformly in PLLA matrix than untreated HNTs. • The interfacial adhesion between D-HNTs and PLLA matrix was obviously improved. • D-HNTs/PLLA fiber membrane has better tensile properties compared with HNTs/PLLA. • The D-HNTs/PLLA fiber membrane is favorable to cell adhesion and proliferation. - Abstract: To improve the dispersion and interfacial interaction between halloysite nanotubes (HNTs) and poly(L-lactide) (PLLA) matrix, and hence to increase the mechanical properties and cytocompatibility of the HNTs/PLLA composite, a facile approach was developed to prepare polydopamine-coated HNTs (D-HNTs) by the self-polymerization of dopamine (DOPA), and then HNTs and D-HNTs were further introduced into PLLA matrix to fabricate HNTs/PLLA and D-HNTs/PLLA fiber membranes based on electrospinning technique. The successful immobilization of the polydopamine (PDOPA) coating on the surfaces of HNTs was confirmed, and such PDOPA coating played an important role in improving the interfacial interaction between the nanotubes and PLLA matrix. The D-HNTs were dispersed in the matrix more uniformly than untreated HNTs, and relative smooth and uniform fiber were obtained for the D-HNTs/PLLA fiber membrane. As a result, the tensile strength and modulus of the D-HNTs/PLLA fiber membrane were obviously superior to those of the HNTs/PLLA fiber membrane. Cell culture results revealed that D-HNTs/PLLA fiber membrane was more effectively to promote MC3T3-E1 cells adhesion and proliferation than neat PLLA and HNTs/PLLA fiber membrane.

  10. Triethyl orthoformate mediated a novel crosslinking method for the preparation of hydrogels for tissue engineering applications: characterization and in vitro cytocompatibility analysis

    Energy Technology Data Exchange (ETDEWEB)

    Yar, Muhammad, E-mail: drmyar@ciitlahore.edu.pk [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Shahzad, Sohail [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Siddiqi, Saadat Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Mahmood, Nasir [Department of Allied Health Sciences and Chemical Pathology, Department of Human Genetics and Molecular Biology, University of Health Sciences, Lahore (Pakistan); Rauf, Abdul [Department of Chemistry, The Islamia University of Bahawalpur, Bahawalpur 63100 (Pakistan); Anwar, Muhammad Sabieh [Department of Physics, Syed Babar Ali School of Science and Engineering, Lahore University of Management Sciences (LUMS), Opposite Sector U, D.H.A., Lahore 54792 (Pakistan); Chaudhry, Aqif Anwar [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Rehman, Ihtesham ur [Interdisciplinary Research Center in Biomedical Materials, COMSATS Institute of Information Technology, Lahore 54000 (Pakistan); Department of Materials Science and Engineering, The Kroto Research Institute, The University of Sheffield, North Campus, Broad Lane, Sheffield S3 7HQ (United Kingdom)

    2015-11-01

    This paper describes the development of a new crosslinking method for the synthesis of novel hydrogel films from chitosan and PVA for potential use in various biomedical applications. These hydrogel membranes were synthesized by blending different ratios of chitosan (CS) and poly(vinyl alcohol) (PVA) solutions and were crosslinked with 2.5% (w/v) triethyl orthoformate (TEOF) in the presence of 17% (w/v) sulfuric acid. The physical/chemical interactions and the presence of specific functional groups in the synthesized materials were evaluated by Fourier transform infrared (FT-IR) spectroscopy. The morphology, structure and pore size of the materials were investigated by scanning electron microscopy (SEM). Thermal gravimetric analysis (TGA) proved that these crosslinked hydrogel films have good thermal stability which was decreased as the CS ratio was increased. Differential scanning calorimetry (DSC) exhibited that CS and PVA were present in the amorphous form. The solution absorption properties were performed in phosphate buffer saline (PBS) solution of pH 7.4. The 20% PVA–80% CS crosslinked hydrogel films showed a greater degree of solution absorption (183%) as compared to other compositions. The hydrogels with greater CS concentration (60% and 80%) demonstrated relatively more porous structure, better cell viability and proliferation and also revealed good blood clotting ability even after crosslinking. Based on the observed facts these hydrogels can be tailored for their potential utilization in wound healing and skin tissue engineering applications. - Highlights: • A new method for covalently crosslinking of chitosan and PVA. • Triethyl orthoformate (TEOF) a new polymer–polymer crosslinking agent. • Hydrogels displayed a good solution absorption capacity. • Hydrogels demonstrated good cytocompatibility. • Good blood clotting potential was shown by these scaffolds.

  11. Surface mechanical properties, corrosion resistance, and cytocompatibility of nitrogen plasma-implanted nickel-titanium alloys: a comparative study with commonly used medical grade materials.

    Science.gov (United States)

    Yeung, K W K; Poon, R W Y; Chu, P K; Chung, C Y; Liu, X Y; Lu, W W; Chan, D; Chan, S C W; Luk, K D K; Cheung, K M C

    2007-08-01

    Stainless steel and titanium alloys are the most common metallic orthopedic materials. Recently, nickel-titanium (NiTi) shape memory alloys have attracted much attention due to their shape memory effect and super-elasticity. However, this alloy consists of equal amounts of nickel and titanium, and nickel is a well known sensitizer to cause allergy or other deleterious effects in living tissues. Nickel ion leaching is correspondingly worse if the surface corrosion resistance deteriorates. We have therefore modified the NiTi surface by nitrogen plasma immersion ion implantation (PIII). The surface chemistry and corrosion resistance of the implanted samples were studied and compared with those of the untreated NiTi alloys, stainless steel, and Ti-6Al-4V alloy serving as controls. Immersion tests were carried out to investigate the extent of nickel leaching under simulated human body conditions and cytocompatibility tests were conducted using enhanced green fluorescent protein mice osteoblasts. The X-ray photoelectron spectroscopy results reveal that a thin titanium nitride (TiN) layer with higher hardness is formed on the surface after nitrogen PIII. The corrosion resistance of the implanted sample is also superior to that of the untreated NiTi and stainless steel and comparable to that of titanium alloy. The release of nickel ions is significantly reduced compared with the untreated NiTi. The sample with surface TiN exhibits the highest amount of cell proliferation whereas stainless steel fares the worst. Compared with coatings, the plasma-implanted structure does not delaminate as easily and nitrogen PIII is a viable way to improve the properties of NiTi orthopedic implants.

  12. 壳聚糖纳米银复合物基温敏水凝胶的抑菌性及细胞相容性研究%Antibacterial activity and cytocompatibility of chitosan-nano-silver complex thermosensitive hydrogel

    Institute of Scientific and Technical Information of China (English)

    李高青; 桑青; 崔凯

    2016-01-01

    Objective To explore the antibacterial activity and cytocompatibility of chitosan-nano-silver complex thermosensitive hydrogel. Methods There were 4 groups: group A (containing 1 ×10-5 chitosan-nano-silver complex thermosensitive hydrogel), group B (containing 5 ×10-6 chitosan-nano-silver complex thermosensitive hydrogel) , group C ( containing 2 ×10-6 chitosan-nano-silver complex thermosensitive hydrogel) , group D ( chitosan thermosensitive hydrogel ) .The antibacterial activity of the samples against six kinds of gram-negative bacteria, one kind of gram-positive bacterium, three kinds of fungi were measured by bacteriostatic circle.The cytocompatibility of the extraction to NIH-3T3 cells was studied by SRB. Results The antibacterial activity enhanced with the increasing of nano silver concentration in chitosan-nano-silver complex thermosensitive hydrogel, whose antibacterial activity was better than chitosan thermosensitive hydrogel; its extraction has no cytotoxicity, thus showed good cytocompatibility. Conclusion The chitosan-nano-silver complex thermosensitive hydrogel is a potential novel wound dressing.%目的:以实验室自制的壳聚糖纳米银复合物基温敏水凝胶为材料,探讨其抑菌性及细胞相容性。方法设置4组:A (含纳米银1×10-5的壳聚糖纳米银复合物基温敏水凝胶),B(含纳米银5×10-6的壳聚糖纳米银复合物基温敏水凝胶),C(含纳米银2×10-6的壳聚糖纳米银复合物基温敏水凝胶),D(壳聚糖温敏水凝胶,不含纳米银)。通过抑菌圈法测定4种样品对6种革兰阴性菌,1种革兰阳性菌,3种真菌的抑菌作用;以SRB法测定其浸提液的细胞相容性。结果随着壳聚糖纳米银复合物基温敏水凝胶中纳米银含量增加,抑菌作用增强,壳聚糖纳米银复合物基温敏水凝胶的抑菌作用优于壳聚糖温敏水凝胶;其浸提液无细胞毒性,具有良好的细胞相容性。结论壳聚

  13. Cytocompatibility and Mechanical Properties of Short Phosphate Glass Fibre Reinforced Polylactic Acid (PLA Composites: Effect of Coupling Agent Mediated Interface

    Directory of Open Access Journals (Sweden)

    Gavin Walker

    2012-10-01

    Full Text Available In this study three chemical agents Amino-propyl-triethoxy-silane (APS, sorbitol ended PLA oligomer (SPLA and Hexamethylene diisocyanate (HDI were identified to be used as coupling agents to react with the phosphate glass fibre (PGF reinforcement and the polylactic acid (PLA polymer matrix of the composite. Composites were prepared with short chopped strand fibres (l = 20 mm, ϕ = 20 µm in a random arrangement within PLA matrix. Improved, initial composite flexural strength (~20 MPa was observed for APS treated fibres, which was suggested to be due to enhanced bonding between the fibres and polymer matrix. Both APS and HDI treated fibres were suggested to be covalently linked with the PLA matrix. The hydrophobicity induced by these coupling agents (HDI, APS helped to resist hydrolysis of the interface and thus retained their mechanical properties for an extended period of time as compared to non-treated control. Approximately 70% of initial strength and 65% of initial modulus was retained by HDI treated fibre composites in contrast to the control, where only ~50% of strength and modulus was retained after 28 days of immersion in PBS at 37 °C. All coupling agent treated and control composites demonstrated good cytocompatibility which was comparable to the tissue culture polystyrene (TCP control, supporting the use of these materials as coupling agent’s within medical implant devices.

  14. Gas Permeation, Mechanical Behavior and Cytocompatibility of Ultrathin Pure and Doped Diamond-Like Carbon and Silicon Oxide Films

    Directory of Open Access Journals (Sweden)

    Juergen M. Lackner

    2013-12-01

    Full Text Available Protective ultra-thin barrier films gather increasing economic interest for controlling permeation and diffusion from the biological surrounding in implanted sensor and electronic devices in future medicine. Thus, the aim of this work was a benchmarking of the mechanical oxygen permeation barrier, cytocompatibility, and microbiological properties of inorganic ~25 nm thin films, deposited by vacuum deposition techniques on 50 µm thin polyetheretherketone (PEEK foils. Plasma-activated chemical vapor deposition (direct deposition from an ion source was applied to deposit pure and nitrogen doped diamond-like carbon films, while physical vapor deposition (magnetron sputtering in pulsed DC mode was used for the formation of silicon as well as titanium doped diamond-like carbon films. Silicon oxide films were deposited by radio frequency magnetron sputtering. The results indicate a strong influence of nanoporosity on the oxygen transmission rate for all coating types, while the low content of microporosity (particulates, etc. is shown to be of lesser importance. Due to the low thickness of the foil substrates, being easily bent, the toughness as a measure of tendency to film fracture together with the elasticity index of the thin films influence the oxygen barrier. All investigated coatings are non-pyrogenic, cause no cytotoxic effects and do not influence bacterial growth.

  15. Glycosaminoglycan-functionalized poly-lactide-co-glycolide nanoparticles: synthesis, characterization, cytocompatibility, and cellular uptake

    Directory of Open Access Journals (Sweden)

    Lamichhane SP

    2015-01-01

    Full Text Available Surya P Lamichhane,1 Neha Arya,1,2 Nirdesh Ojha,3 Esther Kohler,1 V Prasad Shastri1,2,41Institute for Macromolecular Chemistry, University of Freiburg, Freiburg, 2Helmholtz Virtual Institute on “Multifunctional Biomaterials for Medicine”, 3Laboratory for Process Technology, Department of Microsystems Engineering, University of Freiburg, Freiburg, 4Centre for Biological Signaling Studies (BIOSS, University of Freiburg, Freiburg, GermanyAbstract: The efficient delivery of chemotherapeutics to the tumor via nanoparticle (NP-based delivery systems remains a significant challenge. This is compounded by the fact that the tumor is highly dynamic and complex environment composed of a plurality of cell types and extracellular matrix. Since glycosaminoglycan (GAG production is altered in many diseases (or pathologies, NPs bearing GAG moieties on the surface may confer some unique advantages in interrogating the tumor microenvironment. In order to explore this premise, in the study reported here poly-lactide-co-glycolide (PLGA NPs in the range of 100–150 nm bearing various proteoglycans were synthesized by a single-step nanoprecipitation and characterized. The surface functionalization of the NPs with GAG moieties was verified using zeta potential measurements and X-ray photoelectron spectroscopy. To establish these GAG-bearing NPs as carriers of therapeutics, cellular toxicity assays were undertaken in lung epithelial adenocarcinoma (A549 cells, human pulmonary microvascular endothelial cells (HPMEC, and renal proximal tubular epithelial cells. In general NPs were well tolerated over a wide concentration range (100–600 µg/mL by all cell types and were taken up to appreciable extents without any adverse cell response in A549 cells and HPMEC. Further, GAG-functionalized PLGA NPs were taken up to different extents in A459 cells and HPMEC. In both cell systems, the uptake of heparin-modified NPs was diminished by 50%–65% in comparison to that of

  16. Bioactivity and cytocompatibility of dicalcium phosphate/poly (amino acid) biocomposite with degradability

    Science.gov (United States)

    Zhang, Yunfei; Shan, Wenpeng; Li, Xiangde; Wei, Jie; Li, Hong; Ma, Jian; Yan, Yonggang

    2012-01-01

    A bioactive composite of dicalcium phosphate (DCP) and poly (amino acid) (PAA) was fabricated, and the in vitro bioactivity, degradability, and cellular responses to the DCP/PAA composite (DPC) were investigated as compared to PAA. Apatite formation on DPC surfaces occurred after immersion into simulated body fluid (SBF) for 7 days, but not on the surface of PAA. The weight loss ratio of DPC could reach 18.6 ± 0.3 wt% after soaking into phosphate buffered saline (PBS) for 2 months, which was higher than PAA (11.0 ± 0.2 wt%). Cell attachment and proliferation of MG-63 cells on DPC was obviously higher than on PAA. Moreover, the cells spread and formed confluent layer on the DPC surfaces. The alkaline phosphatase activity (ALP) of the cells on DPC was significantly greater than PAA at day 5 and day 7. The results suggested that introducing DCP into PAA makes the composite bioactive and more degradable, and meanwhile enhances osteoblast-like cells attach, proliferation and osteogenic differentiation.

  17. Bioactivity and cytocompatibility of dicalcium phosphate/poly (amino acid) biocomposite with degradability

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Yunfei [College of Chemistry, Sichuan University, Chengdu 610064 (China); Shan Wenpeng; Li Xiangde [Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Wei Jie, E-mail: biomater2006@yahoo.com.cn [Key Laboratory for Ultrafine Materials of Ministry of Education, East China University of Science and Technology, Shanghai 200237 (China); Li Hong [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China); Ma Jian [Hospital of Stomatology, Tongji University, Shanghai 200072 (China); Yan Yonggang, E-mail: yan_yonggang@vip.163.com [College of Physical Science and Technology, Sichuan University, Chengdu 610064 (China)

    2012-01-15

    A bioactive composite of dicalcium phosphate (DCP) and poly (amino acid) (PAA) was fabricated, and the in vitro bioactivity, degradability, and cellular responses to the DCP/PAA composite (DPC) were investigated as compared to PAA. Apatite formation on DPC surfaces occurred after immersion into simulated body fluid (SBF) for 7 days, but not on the surface of PAA. The weight loss ratio of DPC could reach 18.6 {+-} 0.3 wt% after soaking into phosphate buffered saline (PBS) for 2 months, which was higher than PAA (11.0 {+-} 0.2 wt%). Cell attachment and proliferation of MG-63 cells on DPC was obviously higher than on PAA. Moreover, the cells spread and formed confluent layer on the DPC surfaces. The alkaline phosphatase activity (ALP) of the cells on DPC was significantly greater than PAA at day 5 and day 7. The results suggested that introducing DCP into PAA makes the composite bioactive and more degradable, and meanwhile enhances osteoblast-like cells attach, proliferation and osteogenic differentiation.

  18. Cytocompatibility and mechanical properties of novel porous 316 L stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Kato, Komei, E-mail: kkato@mmc.co.jp [Mitsubishi Material Corp. 1-297 Kitabukuro-cho, Omiya-ku, Saitama, 330-8508 (Japan); Yamamoto, Akiko [Biomaterials Center, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); International Center for Materials Nanoarchitectonics (WPI-MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan); Ochiai, Shojiro [Department of Materials Science and Engineering, Graduate School of Engineering, Kyoto University, Yoshida, Sakyo-ku, Kyoto 606-8501 (Japan); Wada, Masahiro; Daigo, Yuzo [Mitsubishi Materials Corp. Advanced and Tools Company, High Performance Alloy Products Div. 476 Shimoishido-shimo, Kitamoto, Saitama 364-0023 (Japan); Kita, Koichi [Mitsubishi Materials C.M.I. Corp. Alloy Products Div. 46-1 Sempuku Susono Shizuoka-ken 410-1116 (Japan); Omori, Kenichi [Biomaterials Center, National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044 (Japan)

    2013-07-01

    Novel 316 L stainless steel (SS) foam with 85% porosity and an open pore diameter of 70–440 μm was developed for hard tissue application. The foam sheet with a 200-μm diameter had superior cell proliferation and penetration as identified through in vitro experiments. Calcification of human osteosarcoma cells in the SS foam was observed. Multi-layered foam preparation is a potential alternative technique that satisfies multi-functional requirements such as cell penetration and binding strength to the solid metal. In tensile tests, Young's modulus and the strength of the SS foam were 4.0 GPa and 11.2 MPa respectively, which is comparable with human cancellous bone. - Highlights: • Novel 316 L stainless steel foam with 85% porosity and a pore diameter of 70–440 μm was developed. • The optimum pore diameter of the foam was 200 μm for cell proliferation and penetration. • Cell penetration in the multi-layered foam was controlled by the pore structures of the top layer. • Calcification of human osteosarcoma was confirmed in the foam and increased with incubation time. • Young's modulus and the tensile strength of the foam were comparable with human cancellous bone.

  19. [Research on the extracorporeal cytocompatibility of a composite of HA, carbon fiber and polyetheretherket-one].

    Science.gov (United States)

    Liu, Xueyong; Deng, Chunbo; Liu, Jiquan; Li, Jianjun; Sui, Guoxin

    2011-12-01

    The present research was to study the biocompatibility of a composite of hydroxyapatite (HA), carbon fiber (CF) and polyetheretherket-one (PEEK) by co-culturing with the osteoblasts in vitro. Cell relative growth (RGR) was used as a quantitative assessment for cytotoxicity of the biomaterials by CCK-8. The proliferation index of the co-cultured cells and ALP activity was measured to study the effect of PEEK-HA-CF composites. Morphological properties of the osteoblast cells in vitro were observed by scanning electro-microscopy (SEM). The PEEK-HA-CF materials have no cytotoxicity to osteoblasts. The proliferation index of PEEK-HA-CF was higher than that of Ti alloy group, but these was no significant difference compared to that of control group. The ALP activity was the highest on PEEK-HA-CF composites surface after 7 days. The osteoblast cells co-cultured with the PEEK-HA-CF composite were adhered well to the biomaterial as observed under the SEM. The results suggested that the PEEK-HA-CF composites had good biocompatibility in vitro and might be a novel orthopedic implanted material.

  20. Fabrication, nanomechanical characterization, and cytocompatibility of gold-reinforced chitosan bio-nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Patel, Nimitt G. [Department of Mechanical and Aeronautical Engineering, Clarkson University, Potsdam, NY, 13699 (United States); Materials Science and Engineering PhD Program, Clarkson University, Potsdam, NY, 13699 (United States); Kumar, Ajeet [Center for Advanced Materials Processing, Clarkson University, Potsdam, NY, 13699 (United States); Jayawardana, Veroni N. [Department of Mathematics, Clarkson University, Potsdam, NY, 13699 (United States); Woodworth, Craig D. [Department of Biology, Clarkson University, Potsdam, NY, 13699 (United States); Yuya, Philip A., E-mail: pyuya@clarkson.edu [Department of Mechanical and Aeronautical Engineering, Clarkson University, Potsdam, NY, 13699 (United States)

    2014-11-01

    Chitosan, a naturally derived polymer represents one of the most technologically important classes of active materials with applications in a variety of industrial and biomedical fields. Gold nanoparticles (∼ 32 nm) were synthesized via a citrate reduction method from chloroauric acid and incorporated in Chitosan matrix. Bio-nanocomposite films with varying concentrations of gold nanoparticles were prepared through solution casting process. Uniform distribution of gold nanoparticles was achieved throughout the chitosan matrix and was confirmed with SEM. Synthesis outcomes and prepared nanocomposites were characterized using SEM, TEM, EDX, SAED, UV–vis, XRD, DLS, and Zeta potential for their physical, morphological and structural properties. Nanoscale properties of materials under the influence of temperature were characterized through nanoindentation techniques. From quasi-static nanoindentation, it was observed that hardness and reduced modulus of the nanocomposites were increased significantly in direct proportion to the gold nanoparticle concentration. Gold nanoparticle concentration also showed positive impact on storage modulus and thermal stability of the material. The obtained films were confirmed to be biocompatible by their ability to support growth of human cells in vitro. In summary, the results show enhanced mechanical properties with increasing gold nanoparticle concentration, and provide better understanding of the structure–property relationships of such biocompatible materials for potential biomedical applications. - Highlights: • We fabricated gold reinforced chitosan nanocomposite for biomedical applications. • Gold nanoparticles significantly enhanced nanomechanical properties of chitosan. • Nanocomposite films supported growth of human cells in vitro. • Gold nanoparticles significantly improved cell proliferation on chitosan films.

  1. In vitro bioactivity and cytocompatibility of porous scaffolds of bioactive borosilicate glasses

    Institute of Scientific and Technical Information of China (English)

    ZHANG Xin; FU HaiLuo; LIU Xin; YAO AiHua; WANG DePing; HUANG WenHai; ZHAO Ying; JIANG XinQuan

    2009-01-01

    The bioactive borosilicate scaffolds (R2O-RO-B2O3-SiO2-P2O5) with four different contents of borate were fabricated by replication technique. The bioactivity,degradability and the cytotoxicity of the scaffolds were studied in this paper. The porosity of the scaffolds was found to be 73%-80%,and the pore size was in the range of 200-300 μm. The porous scaffolds immersed in 0.02 mol. L-1 K2HPO4 solution were transformed into hydroxyapatite. And it is notable that the D-AIk-2B,D-AIk-3B-scaffolds were covered by hydroxyapatite layers after 7 h-immersion,which proved their high bioactivity. In the cell adhesion test,cells could be seen growing well on the scaffolds,showing stretched morphology and obvious pseudopodia,and only the high cumulative concentration of B ions released from the D-AIk-3B-scaffold samples had an inhibition effect on cell proliferation. But the inhibition effect could be alleviated by diluting the extract solution to a certain concentration (dilution ratio:1:8). Therefore,after suitable pretreatment,the porous borosilicate bioactive glass scaffold can be e desirable candidate for bone tissue engineering.

  2. Apatite forming ability and cytocompatibility of pure and Zn-doped bioactive glasses.

    Science.gov (United States)

    Oudadesse, H; Dietrich, E; Gal, Y L; Pellen, P; Bureau, B; Mostafa, A A; Cathelineau, G

    2011-06-01

    The use of bone grafts permits the filling of a bone defect without risk of virus transmission. In this work, pure bioactive glass (46S6) and zinc-doped bioactive glass (46S6Zn10) with 0.1 wt% zinc are used to elaborate highly bioactive materials by melting and rapid quenching. Cylinders of both types of glasses were soaked in a simulated body fluid (SBF) solution with the aim of determining the effect of zinc addition as a trace element on the chemical reactivity and bioactivity of glass. Several physico-chemical characterization methods such as x-ray diffraction, Fourier transform infrared spectroscopy and nuclear magnetic resonance methods, with particular focus on the latter, were chosen to investigate the fine structural behaviour of pure and Zn-doped bioactive glasses as a function of the soaking time of immersion in SBF. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) was used to measure the concentrations of Ca and P ions in the SBF solution after different durations of immersion. The effect of the investigated samples on the proliferation rate of human osteoblast cells was assessed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, and tested on two different sizes of pure and zinc-doped glasses in powder form, with particle sizes that ranged between 40 to 63 µm and 500 to 600 µm. The obtained results showed the delay release of ions by Zn-doped glass (46S6Zn10) and the slower CaP deposition. Cytotoxicity and cell viability were affected by the particle size of the glass. The release rate of ions was found to influence the cell viability.

  3. Drug delivery property, bactericidal property and cytocompatibility of magnetic mesoporous bioactive glass

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Yi-Zhuo [The Education Ministry Key Lab of Resource Chemistry, Shanghai Normal University, Shanghai 200234 (China); Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Li, Yang [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Yu, Xi-Bin [The Education Ministry Key Lab of Resource Chemistry, Shanghai Normal University, Shanghai 200234 (China); Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China); Liu, Li-Na [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Zhu, Zhen-An, E-mail: zhuzhenan2006@126.com [Shanghai Key Laboratory of Orthopedic Implant, Department of Orthopedic Surgery, Shanghai Ninth People' s Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai 200011 (China); Guo, Ya-Ping, E-mail: ypguo@shnu.edu.cn [The Education Ministry Key Lab of Resource Chemistry, Shanghai Normal University, Shanghai 200234 (China); Shanghai Key Laboratory of Rare Earth Functional Materials, Shanghai Normal University, Shanghai 200234 (China)

    2014-08-01

    A multifunctional magnetic mesoporous bioactive glass (MMBG) has been widely used for a drug delivery system, but its biological properties have been rarely reported. Herein, the effects of mesopores and Fe{sub 3}O{sub 4} nanoparticles on drug loading–release property, bactericidal property and biocompatibility have been investigated by using mesoporous bioactive glass (MBG) and non-mesoporous bioactive glass (NBG) as control samples. Both MMBG and MBG have better drug loading efficiency than NBG because they possess ordered mesoporous channels, big specific surface areas and high pore volumes. As compared with MBG, the Fe{sub 3}O{sub 4} nanoparticles in MMBG not only provide magnetic property, but also improve sustained drug release property. For gentamicin-loaded MMBG (Gent-MMBG), the sustained release of gentamicin and the Fe{sub 3}O{sub 4} nanoparticles minimize bacterial adhesion significantly and prevent biofilm formation against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis). Moreover, the magnetic Fe{sub 3}O{sub 4} nanoparticles in MMBG can promote crucial cell functions such as cell adhesion, spreading and proliferation. The excellent biocompatibility and drug delivery property of MMBG suggest that Gent-MMBG has great potentials for treatment of implant-associated infections. - Highlights: • Multifunctional magnetic mesoporous bioactive glass is fabricated. • The bioactive glass has great biocompatibility. • The bioactive glass exhibits high drug loading–release properties. • The drug delivery system has bactericidal property. • Magnetic particles improve cell adhesion, spreading and proliferation.

  4. Apatite forming ability and cytocompatibility of pure and Zn-doped bioactive glasses

    Energy Technology Data Exchange (ETDEWEB)

    Oudadesse, H; Dietrich, E; Gal, Y L; Pellen, P; Bureau, B; Mostafa, A A; Cathelineau, G, E-mail: hassane.oudadesse@univ-rennes1.fr [SCR, UMR-CNRS 6226, Campus de Beaulieu, Universite de Rennes 1, 263 Avenue du General Leclerc, 35042 Rennes Cedex (France)

    2011-06-15

    The use of bone grafts permits the filling of a bone defect without risk of virus transmission. In this work, pure bioactive glass (46S6) and zinc-doped bioactive glass (46S6Zn10) with 0.1 wt% zinc are used to elaborate highly bioactive materials by melting and rapid quenching. Cylinders of both types of glasses were soaked in a simulated body fluid (SBF) solution with the aim of determining the effect of zinc addition as a trace element on the chemical reactivity and bioactivity of glass. Several physico-chemical characterization methods such as x-ray diffraction, Fourier transform infrared spectroscopy and nuclear magnetic resonance methods, with particular focus on the latter, were chosen to investigate the fine structural behaviour of pure and Zn-doped bioactive glasses as a function of the soaking time of immersion in SBF. Inductively coupled plasma-optical emission spectroscopy (ICP-OES) was used to measure the concentrations of Ca and P ions in the SBF solution after different durations of immersion. The effect of the investigated samples on the proliferation rate of human osteoblast cells was assessed by the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assay, and tested on two different sizes of pure and zinc-doped glasses in powder form, with particle sizes that ranged between 40 to 63 {mu}m and 500 to 600 {mu}m. The obtained results showed the delay release of ions by Zn-doped glass (46S6Zn10) and the slower CaP deposition. Cytotoxicity and cell viability were affected by the particle size of the glass. The release rate of ions was found to influence the cell viability.

  5. Surface characterization, hemo- and cytocompatibility of segmented poly(dimethylsiloxane-based polyurethanes

    Directory of Open Access Journals (Sweden)

    Pergal Marija V.

    2014-01-01

    Full Text Available Segmented polyurethanes based on poly(dimethylsiloxane, currently used for biomedical applications, have sub-optimal biocompatibility which reduces their efficacy. Improving the endothelial cell attachment and blood-contacting properties of PDMS-based copolymers would substantially improve their clinical applications. We have studied the surface properties and in vitro biocompatibility of two series of segmented poly(urethane-dimethylsiloxanes (SPU-PDMS based on hydroxypropyl- and hydroxyethoxypropyl- terminated PDMS with potential applications in blood-contacting medical devices. SPU-PDMS copolymers were characterized by contact angle measurements, surface free energy determination (calculated using the van Oss-Chaudhury-Good and Owens-Wendt methods, and atomic force microscopy. The biocompatibility of copolymers was evaluated using an endothelial EA.hy926 cell line by direct contact assay, before and after pre-treatment of copolymers with multicomponent protein mixture, as well as by a competitive blood-protein adsorption assay. The obtained results suggested good blood compatibility of synthesized copolymers. All copolymers exhibited good resistance to fibrinogen adsorption and all favored albumin adsorption. Copolymers based on hydroxyethoxypropyl-PDMS had lower hydrophobicity, higher surface free energy, and better microphase separation in comparison with hydroxypropyl-PDMS-based copolymers, which promoted better endothelial cell attachment and growth on the surface of these polymers as compared to hydroxypropyl-PDMS-based copolymers. The results showed that SPU-PDMS copolymers display good surface properties, depending on the type of soft PDMS segments, which can be tailored for biomedical application requirements such as biomedical devices for short- and long-term uses. [Projekat Ministarstva nauke Republike Srbije, br. 172062

  6. Stereo imaging and cytocompatibility of a model dental implant surface formed by direct laser fabrication.

    Science.gov (United States)

    Mangano, Carlo; Raspanti, Mario; Traini, Tonino; Piattelli, Adriano; Sammons, Rachel

    2009-03-01

    Direct laser fabrication (DLF) allows solids with complex geometry to be produced by sintering metal powder particles in a focused laser beam. In this study, 10 Ti6Al4V alloy model dental root implants were obtained by DLF, and surface characterization was carried out using stereo scanning electron microscopy to produce 3D reconstructions. The surfaces were extremely irregular, with approximately 100 microm deep, narrow intercommunicating crevices, shallow depressions and deep, rounded pits of widely variable shape and size, showing ample scope for interlocking with the host bone. Roughness parameters were as follows: R(t), 360.8 microm; R(z), 358.4 microm; R(a), 67.4 microm; and R(q), 78.0 microm. Disc specimens produced by DLF with an identically prepared surface were used for biocompatibility studies with rat calvarial osteoblasts: After 9 days, cells had attached and spread on the DLF surface, spanning across the crevices, and voids. Cell density was similar to that on a commercial rough microtextured surface but lower than on commercial smooth machined and smooth-textured grit-blasted, acid-etched surfaces. Human fibrin clot extension on the DLF surface was slightly improved by inorganic acid etching to increase the microroughness. With further refinements, DLF could be an economical means of manufacturing implants from titanium alloys.

  7. Degradation of electrospun PLGA-chitosan/PVA membranes and their cytocompatibility in vitro.

    Science.gov (United States)

    Duan, Bin; Wu, Lili; Li, Xiaoran; Yuan, Xiaoyan; Li, Xiulan; Zhang, Yang; Yao, Kangde

    2007-01-01

    Nanofibrious composite poly(lactide-co-glycolide) (PLGA) and chitosan/poly(vinyl alcohol) (PVA) membranes were prepared by simultaneously electrospinning PLGA and chitosan/PVA from two different syringes. The in vitro degradation of PLGA and cross-linked composite membranes was examined for up to 10 weeks in phosphate-buffered saline (PBS, pH 7.4) at 37 degrees C. The pH of PBS, the weight average molecular weight of PLGA, fiber morphology and mechanical properties, including tensile strength, Young's modulus and elongation-at-break, were measured as a function of degradation time. The fibrous composite membranes were further investigated as a promising scaffold for human embryo skin fibroblasts (hESFs) culture. The cell adhesion and morphology of hESFs seeded on each electrospun membrane was observed using scanning electron microscope and inverted phase contrast microscopy after Wright-Giemsa staining. The introduction of chitosan/PVA component changed the hydrophilic/hydrophobic balance and, thus, influenced degradation behavior and mechanical properties of the composite membranes during degradation. The cells could not only favorably attach and grow well on the composite membranes, but were also able to migrate and infiltrate the membranes. Therefore, the results suggest that the composite membranes can positively mimic the structure of natural extracellular matrices and have the potential for application as three-dimensional tissue-engineering scaffolds.

  8. Drug delivery property, bactericidal property and cytocompatibility of magnetic mesoporous bioactive glass.

    Science.gov (United States)

    Liu, Yi-Zhuo; Li, Yang; Yu, Xi-Bin; Liu, Li-Na; Zhu, Zhen-An; Guo, Ya-Ping

    2014-08-01

    A multifunctional magnetic mesoporous bioactive glass (MMBG) has been widely used for a drug delivery system, but its biological properties have been rarely reported. Herein, the effects of mesopores and Fe3O4 nanoparticles on drug loading-release property, bactericidal property and biocompatibility have been investigated by using mesoporous bioactive glass (MBG) and non-mesoporous bioactive glass (NBG) as control samples. Both MMBG and MBG have better drug loading efficiency than NBG because they possess ordered mesoporous channels, big specific surface areas and high pore volumes. As compared with MBG, the Fe3O4 nanoparticles in MMBG not only provide magnetic property, but also improve sustained drug release property. For gentamicin-loaded MMBG (Gent-MMBG), the sustained release of gentamicin and the Fe3O4 nanoparticles minimize bacterial adhesion significantly and prevent biofilm formation against Staphylococcus aureus (S. aureus) and Staphylococcus epidermidis (S. epidermidis). Moreover, the magnetic Fe3O4 nanoparticles in MMBG can promote crucial cell functions such as cell adhesion, spreading and proliferation. The excellent biocompatibility and drug delivery property of MMBG suggest that Gent-MMBG has great potentials for treatment of implant-associated infections.

  9. Incorporation of strontium up to 5 Mol. (% to hydroxyapatite did not affect its cytocompatibility

    Directory of Open Access Journals (Sweden)

    Débora dos Santos Tavares

    2011-12-01

    Full Text Available The aim of this work was to produce hydroxyapatite (HA granules containing 0, 0.5, 1 and 5 mol. (% of strontium (Sr, evaluate the physico-chemical properties and also the cytotoxicity by three different parameters of cell viability (ISO 10993-5, 10993-12. The physico-chemical characterization was carried out by using X-ray diffraction (XRD, Fourier-transform infrared spectroscopy (FTIR and X-ray fluorescence (XRF. The XRD profile presented the main peaks of HA (JCPDS 860740 and the absorption bands of HA were identified by FTIR. The XRF results showed that the strontium concentration was close to the theoretical value. Regarding the cytotoxicity assays, the incorporation of strontium up to 5 mol. (% to the HA did not affected dehydrogenase activity (XTT, 2,3-bis[2-methyloxy-4-nitro-5-sulfophenyl]-2H-tetrazolium-5-carboxanilide, membrane integrity (neutral red uptake or DNA contend (incorporation of crystal violet, in relation to HA alone. In conclusion, hydroxyapatite containing from 0.5 to 5 mol. (% of Sr was successfully produced and presented no cytotoxicity.

  10. Cytocompatibility of Ar{sup +} plasma treated and Au nanoparticle-grafted PE

    Energy Technology Data Exchange (ETDEWEB)

    Svorcik, V. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic)], E-mail: vaclav.svorcik@vscht.cz; Kasalkova, N.; Slepicka, P. [Department of Solid State Engineering, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Zaruba, K.; Kral, V. [Department of Analytical Chemistry, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Bacakova, L.; Parizek, M.; Lisa, V. [Institute of Physiology, Academy of Sciences of the Czech Republic 142 20 Prague (Czech Republic); Ruml, T.; Gbelcova, H.; Rimpelova, S. [Department of Biochemistry and Microbiology, Institute of Chemical Technology, 166 28 Prague (Czech Republic); Mackova, A. [Nuclear Physics Institute, Academy of Sciences of the Czech Republic, 250 68 Rez (Czech Republic); Department of Physics, J.E. Purkinje University, 400 96 Usti nad Labem (Czech Republic)

    2009-06-01

    Polyethylene (PE) was irradiated with inert Ar plasma, and the chemically active PE surface was grafted with Au nanoparticles. The composition and the structure of the modified PE surface were studied using X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectroscopy (RBS). Changes in the surface wettability were determined from the contact angle measured in a reflection goniometer. The changes in the surface roughness and morphology were followed by atomic force microscopy (AFM). The modified PE samples were seeded with rat vascular smooth muscle cells (VSMC) or mouse NIH 3T3 fibroblasts, and their adhesion and proliferation were studied. We found that plasma discharge and Au grafting lead to dramatic changes in the surface morphology and roughness of PE. The Au nanoparticles were found not only on the sample surface, but also in the sample interior up to the depth of about 100 nm. In addition, plasma modification of the PE surface, followed with grafting Au-nanoparticles, significantly increased the attractiveness of the PE surface for the adhesion and growth of VSMC, and particularly for mouse embryonic 3T3 fibroblasts.

  11. Cytocompatibility of Ar + plasma treated and Au nanoparticle-grafted PE

    Science.gov (United States)

    Švorčík, V.; Kasálková, N.; Slepička, P.; Záruba, K.; Král, V.; Bačáková, L.; Pařízek, M.; Lisá, V.; Ruml, T.; Gbelcová, H.; Rimpelová, S.; Macková, A.

    2009-06-01

    Polyethylene (PE) was irradiated with inert Ar plasma, and the chemically active PE surface was grafted with Au nanoparticles. The composition and the structure of the modified PE surface were studied using X-ray photoelectron spectroscopy (XPS) and Rutherford backscattering spectroscopy (RBS). Changes in the surface wettability were determined from the contact angle measured in a reflection goniometer. The changes in the surface roughness and morphology were followed by atomic force microscopy (AFM). The modified PE samples were seeded with rat vascular smooth muscle cells (VSMC) or mouse NIH 3T3 fibroblasts, and their adhesion and proliferation were studied. We found that plasma discharge and Au grafting lead to dramatic changes in the surface morphology and roughness of PE. The Au nanoparticles were found not only on the sample surface, but also in the sample interior up to the depth of about 100 nm. In addition, plasma modification of the PE surface, followed with grafting Au-nanoparticles, significantly increased the attractiveness of the PE surface for the adhesion and growth of VSMC, and particularly for mouse embryonic 3T3 fibroblasts.

  12. Minocycline-released hydroxyapatite-gelatin nanocomposite and its cytocompatibility in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Dou Xiaochen; Zhu Xiaopeng; Zhou Jian; Cai Huaqiong; Li Quanli [Key Laboratory of Oral Disease Research of Anhui Province, Stomatologic Hospital and Collage, Anhui Medical University, Hefei (China); Tang Jian, E-mail: ql-li@126.com [Department of Orthopedic Surgery, The First Hospital of Anhui Medical University, Hefei (China)

    2011-04-15

    The incorporation of antibacterial agents into biomaterials is extremely desirable for repairing bone defects. Minocycline, a semi-synthetic tetracycline antibiotic, is active against aerobic, anaerobic, Gram-positive and Gram-negative bacteria, and can enhance bone formation, decrease connective tissue breakdown and diminish bone resorption. In this study, a novel minocycline-releasing biomaterial was synthesized using a biomimetic method. A measured amount of an acidic hydroxyapatite and minocycline solution was respectively added to a gelatin solution and kept at 40 deg. C and pH 7-8 for 2 h. The mixture was aged overnight, lyophilized and a hydroxyapatite-gelatin-minocycline composite was obtained. The composite was co-cultured with rat bone marrow stromal cells (BMSCs) in vitro. Our results show that nanohydroxyapatite was distributed evenly in the fibrils of the gelatin. Minocycline was incorporated into the composite and could be released from the composite particles slowly over 2 weeks in vitro. The composite promoted BMSC adhesion, proliferation and differentiation in vitro. The approach described here may provide a basis for the preparation of an antibacterial biomaterial for bone regeneration.

  13. Foldable and Cytocompatible Sol-gel TiO2 Photonics

    Science.gov (United States)

    Li, Lan; Zhang, Ping; Wang, Wei-Ming; Lin, Hongtao; Zerdoum, Aidan B.; Geiger, Sarah J.; Liu, Yangchen; Xiao, Nicholas; Zou, Yi; Ogbuu, Okechukwu; Du, Qingyang; Jia, Xinqiao; Li, Jingjing; Hu, Juejun

    2015-09-01

    Integrated photonics provides a miniaturized and potentially implantable platform to manipulate and enhance the interactions between light and biological molecules or tissues in in-vitro and in-vivo settings, and is thus being increasingly adopted in a wide cross-section of biomedical applications ranging from disease diagnosis to optogenetic neuromodulation. However, the mechanical rigidity of substrates traditionally used for photonic integration is fundamentally incompatible with soft biological tissues. Cytotoxicity of materials and chemicals used in photonic device processing imposes another constraint towards these biophotonic applications. Here we present thin film TiO2 as a viable material for biocompatible and flexible integrated photonics. Amorphous TiO2 films were deposited using a low temperature (sol-gel process fully compatible with monolithic integration on plastic substrates. High-index-contrast flexible optical waveguides and resonators were fabricated using the sol-gel TiO2 material, and resonator quality factors up to 20,000 were measured. Following a multi-neutral-axis mechanical design, these devices exhibit remarkable mechanical flexibility, and can sustain repeated folding without compromising their optical performance. Finally, we validated the low cytotoxicity of the sol-gel TiO2 devices through in-vitro cell culture tests. These results demonstrate the potential of sol-gel TiO2 as a promising material platform for novel biophotonic devices.

  14. Foldable and Cytocompatible Sol-gel TiO2 Photonics.

    Science.gov (United States)

    Li, Lan; Zhang, Ping; Wang, Wei-Ming; Lin, Hongtao; Zerdoum, Aidan B; Geiger, Sarah J; Liu, Yangchen; Xiao, Nicholas; Zou, Yi; Ogbuu, Okechukwu; Du, Qingyang; Jia, Xinqiao; Li, Jingjing; Hu, Juejun

    2015-09-07

    Integrated photonics provides a miniaturized and potentially implantable platform to manipulate and enhance the interactions between light and biological molecules or tissues in in-vitro and in-vivo settings, and is thus being increasingly adopted in a wide cross-section of biomedical applications ranging from disease diagnosis to optogenetic neuromodulation. However, the mechanical rigidity of substrates traditionally used for photonic integration is fundamentally incompatible with soft biological tissues. Cytotoxicity of materials and chemicals used in photonic device processing imposes another constraint towards these biophotonic applications. Here we present thin film TiO2 as a viable material for biocompatible and flexible integrated photonics. Amorphous TiO2 films were deposited using a low temperature (<250 °C) sol-gel process fully compatible with monolithic integration on plastic substrates. High-index-contrast flexible optical waveguides and resonators were fabricated using the sol-gel TiO2 material, and resonator quality factors up to 20,000 were measured. Following a multi-neutral-axis mechanical design, these devices exhibit remarkable mechanical flexibility, and can sustain repeated folding without compromising their optical performance. Finally, we validated the low cytotoxicity of the sol-gel TiO2 devices through in-vitro cell culture tests. These results demonstrate the potential of sol-gel TiO2 as a promising material platform for novel biophotonic devices.

  15. Compatibility of embryonic stem cells with biomaterials.

    Science.gov (United States)

    Handschel, Jörg; Berr, Karin; Depprich, Rita; Naujoks, Christian; Kübler, Norbert R; Meyer, Ulrich; Ommerborn, Michelle; Lammers, Lydia

    2009-05-01

    Periodontal bone defects and atrophy of the jaws in an aging population are of special concern. Tissue engineering using embryonic stem cells (ESCs) and biomaterials may offer new therapeutic options. The purpose of this study is to evaluate the compatibility of ESCs with biomaterials and the influence of biomaterials on the osteogenic gene expression profile.Therefore, ESCs are cultured with various biomaterials. The cytocompatibility of murine ESCs is measured regarding the proliferation of the cells on the materials by CyQUANT assay, the morphology by scanning electron microscopy, and the influence on the gene expression by real time PCR.The results show that insoluble collagenous bone matrix, followed by beta-tricalciumphosphate, is most suitable for bone tissue engineering regarding cell proliferation, and phenotype. The gene expression analysis indicates that biomaterials do influence the gene expression of ESCs.Our results provide new insight into the cytocompatibility of ESCs on different scaffolds.

  16. Effect of Polyethylene Glycol on Properties and Drug Encapsulation-Release Performance of Biodegradable/Cytocompatible Agarose-Polyethylene Glycol-Polycaprolactone Amphiphilic Co-Network Gels.

    Science.gov (United States)

    Chandel, Arvind K Singh; Kumar, Chinta Uday; Jewrajka, Suresh K

    2016-02-10

    We synthesized agarose-polycaprolactone (Agr-PCL) bicomponent and Agr-polyethylene glycol-PCL (Agr-PEG-PCL) tricomponent amphiphilic co-network (APCN) gels by the sequential nucleophilic substitution reaction between amine-functionalized Agr and activated halide terminated PCL or PCL-b-PEG-b-PCL copolymer for the sustained and localized delivery of hydrophilic and hydrophobic drugs. The biodegradability of the APCNs was confirmed using lipase and by hydrolytic degradation. These APCN gels displayed good cytocompatibility and blood compatibility. Importantly, these APCN gels exhibited remarkably high drug loading capacity coupled with sustained and triggered release of both hydrophilic and hydrophobic drugs. PEG in the APCNs lowered the degree of phase separation and enhanced the mechanical property of the APCN gels. The drug loading capacity and the release kinetics were also strongly influenced by the presence of PEG, the nature of release medium, and the nature of the drug. Particularly, PEG in the APCN gels significantly enhanced the 5-fluorouracil loading capacity and lowered its release rate and burst release. Release kinetics of highly water-soluble gemcitabine hydrochloride and hydrophobic prednisolone acetate depended on the extent of water swelling of the APCN gels. Cytocompatibility/blood compatibility and pH and enzyme-triggered degradation together with sustained release of drugs show great promise for the use of these APCN gels in localized drug delivery and tissue engineering applications.

  17. Cytocompatibility, antibacterial activity and biodegradability of self-assembling beta-hairpin peptide-based hydrogels for tissue regenerative applications

    Science.gov (United States)

    Salick, Daphne Ann

    Every year, millions of people suffer from tissue loss or failure. One approach to repair damaged or diseased tissue is through tissue/organ transplantation. However, one of the major problems which exist with this approach is that there are more people in need of a transplant than there are donors. Over the past several decades, scientists and doctors have come together to find a way to overcome this challenge. This collaboration has led to the development of biomimetic scaffolds, which closely mimic the desired tissue of interest to act as a substitute for the unfunctional tissue, with hopes to improve the quality of life. The Schneider and Pochan labs have developed a biomimetic scaffold using self-assembling beta-hairpin peptides. The self-assembly event can be triggered in response to physiological conditions, which is dictated by the monomer, to form non covalently crosslinked mechanically rigid hydrogels. In vitro studies showed that hydrogels were cytocompatible and may not elicit a pro-inflammatory response from murine macrophages. These material properties show promise for the use of these hydrogels in tissue engineering. When implanting a material into a host, a major concern is the introduction of infection. Infection, if not prevented or halted, results in poor tissue integration and function, ultimately leading to implant removal from the host. Interestingly, the beta-hairpin hydrogels were shown to exhibit antibacterial properties against pathogens commonly found in hospital environments. This inherently antibacterial hydrogel is advantageous because it may help decrease or diminish bacterial contamination when implanted in vivo, which may help to increase the success of implants. Also, a unique and exciting feature of these peptide-based hydrogels is their ability to shear-thin and self-heal. Hydrogels can be directly formed in a syringe and be subsequently delivered to a tissue defect in a minimally invasive manner where they will recover to their

  18. Biofabrication of cell-loaded 3D spider silk constructs.

    Science.gov (United States)

    Schacht, Kristin; Jüngst, Tomasz; Schweinlin, Matthias; Ewald, Andrea; Groll, Jürgen; Scheibel, Thomas

    2015-02-23

    Biofabrication is an emerging and rapidly expanding field of research in which additive manufacturing techniques in combination with cell printing are exploited to generate hierarchical tissue-like structures. Materials that combine printability with cytocompatibility, so called bioinks, are currently the biggest bottleneck. Since recombinant spider silk proteins are non-immunogenic, cytocompatible, and exhibit physical crosslinking, their potential as a new bioink system was evaluated. Cell-loaded spider silk constructs can be printed by robotic dispensing without the need for crosslinking additives or thickeners for mechanical stabilization. Cells are able to adhere and proliferate with good viability over at least one week in such spider silk scaffolds. Introduction of a cell-binding motif to the spider silk protein further enables fine-tuned control over cell-material interactions. Spider silk hydrogels are thus a highly attractive novel bioink for biofabrication.

  19. 磷酸钙表面改性镁合金的生物腐蚀性能及细胞相容性%Biocorrosion property and cytocompatibility of calcium phosphate coated Mg alloy

    Institute of Scientific and Technical Information of China (English)

    徐丽萍; 张二林; 杨珂

    2012-01-01

    Calcium phosphate coated Mg alloy was prepared.The phase constitute and surface morphology were identified and observed by X-ray diffractometer (XRD) and SEM.The results show that the coating is composed of flake-like CaHPO4·2H2O crystals.The corrosion resistance of the coated Mg alloy was measured by electrochemical polarization and immersion test in comparison with uncoated Mg alloy.Cytocompatibility was designed by observing the attachment,growth and proliferation of L929 cell on both coated and uncoated Mg alloy samples.The results display that the corrosion resistance of the coated Mg alloy is better than that of uncoated one.The immersion test also shows that the calcium phosphate coating can mitigate the corrosion of Mg alloy substrate,and tends to transform into hydroxyapatite (HA).Compared with uncoated Mg alloy,L929 cells exhibit good adherence,growth and proliferation characteristics on the coated Mg alloy,indicating that the cytocompatibility is significantly improved with the calcium phosphate coating.%在镁合金表面制备磷酸钙涂层,利用X射线衍射仪确定涂层的相组成.用扫描电镜观察涂层的微观形貌.结果表明,涂层由板条状的CaHPO4·2H2O晶体组成.采用电化学测试和浸泡实验研究磷酸钙改性镁合金的生物腐蚀性能,并与未改性合金进行对比.通过观察L929细胞在材料表面的粘附生长状况来评价材料的生物相容性.电化学测试结果表明,磷酸钙改性镁合金比未改性合金显示出更好的耐腐蚀性能.浸泡实验表明,磷酸钙涂层可以减缓合金的腐蚀,且在浸泡过程中磷酸钙涂层发生了向羟基磷灰石(HA)的转变.与未改性合金相比,L929细胞在磷酸钙改性镁合金表面显示出良好的粘附、生长和分化特征,表明磷酸钙改性能明显提高基体合金的细胞相容性.

  20. Influence of non-thermal TiCl4/Ar+O2 plasma-assisted TiOx based coatings on the surface of polypropylene (PP) films for the tailoring of surface properties and cytocompatibility.

    Science.gov (United States)

    Pandiyaraj, K N; Kumar, A Arun; Ramkumar, M C; Sachdev, A; Gopinath, P; Cools, Pieter; De Geyter, N; Morent, R; Deshmukh, R R; Hegde, P; Han, C; Nadagouda, M N

    2016-05-01

    The superior bulk properties (corrosion resistance, high strength to weight ratio, relatively low cost and easy processing) of hydrocarbon based polymers such as polypropylene (PP) have contributed significantly to the development of new biomedical applications such as artificial organs and cell scaffolds. However, low cell affinity is one of the main draw backs for PP due to its poor surface properties. In tissue engineering, physico-chemical surface properties such as hydrophilicity, polar functional groups, surface charge and morphology play a crucial role to enrich the cell proliferation and adhesion. In this present investigation TiOx based biocompatible coatings were developed on the surface of PP films via DC excited glow discharge plasma, using TiCl4/Ar+O2 gas mixture as a precursor. Various TiOx-based coatings are deposited on the surface of PP films as a function of discharge power. The changes in hydrophilicity of the TiOx/PP film surfaces were studied using contact angle analysis and surface energy calculations by Fowke's approximation. X-ray photo-electron spectroscopy (XPS) was used to investigate the surface chemical composition of TiOx/PP films. The surface morphology of the obtained TiOx/PP films was investigated by scanning electron and transmission electron microscopy (SEM &TEM). Moreover, the surface topography of the material was analyzed by atomic force microscopy (AFM). The cytocompatibility of the TiOx/PP films was investigated via in vitro analysis (cell viability, adhesion and cytotoxicity) using NIH3T3 (mouse embryonic fibroblast) cells. Furthermore the antibacterial activities of TiOx/PP films were also evaluated against two distinct bacterial models namely Gram positive Staphylococcus aureus (S.aureus) and Gram negative Escherichia coli DH5α. (E.coli) bacteria. XPS results clearly indicate the successful incorporation of TiOx and oxygen containing polar functional groups on the surface of plasma treated PP films. Moreover the surface

  1. 聚D,L-乳酸多孔支架的体外相容性研究%In vitro cytocompatibility of poly-D, L-lactic acid porous scaffolds

    Institute of Scientific and Technical Information of China (English)

    朱水涛; 王群波; 邵高海; 卢旻鹏; 余雨; 李波

    2015-01-01

    as controls.Cell viability,cytotoxicity,and osteogenic differentiation were detected for study on cytocompatibility of PDLLA.Scanning electron microscopy was used to observe the growth of BMSCs on the surface of PDLLA scaffolds.Results PDLLA scaffolds presented no significant cytotoxic on the growth of BMSCs.PDLLA scaffolds had no negative effect on cell viability compared with the controls (t3 =-0.441,P =0.671; t6 =1.596,P =0.154; t9 =-0.492,P =0.636; t12 =-1.135,P=0.283).ALP staining and calcium nodule staining were positive and there were no significant differences in ALP and collagen Ⅰ protein quantitative detection compared with the controls.BMSCs grew well on the inner surface of the PDLLA three-dimensional porous scaffolds.Conclusion Three-dimensional porous scaffolds of PDLLA present good cytocompatibility in vitro and can be used as bone tissue engineering scaffolds for subsequent in vivo research.

  2. Preparation and in vitro cytocompatibility of collagen sponge from newborn bovine skin%新生牛皮胶原蛋白海绵的制备及其体外细胞相容性

    Institute of Scientific and Technical Information of China (English)

    马忠仁; 冯玉萍; 李明生; 冯若飞; 乔自林; 李琼毅; 侯兰新; 李倬

    2008-01-01

    newborn bovine skin,prepare the collagen sponge for biomedical application,and observe the biocompatibility and cytocompatibility of collagen sponge with lamb fibroblasts.DESIGN,TIME AND SETTING:Controlled study was performed in the Key Laboratory of Bioengineering of State Ethical Committee,Life Science and Engineering College,Northwest University for Nationalities from May 2006 to February 2007.MATERIALS:Newborn Galiba bovine within 24 hours and black fur lamb kidney fibroblasts were used.METHODS:Newborn bovine skin was harvested to prepare the collagen sponge with a series of procedures,including depilation,pepsin+glacial acetic acid,salting-out,dialysis and freeze drying.The obtained collagen sponge was inoculated with fibroblast suspension,which were divided into collagen sponge group,negative control group (saline) and positive control group (rubber bung leaching liquor).MAIN OUTCOME MEASURES:Inverted phase contrast microscope and JVC digital camera system were used to observe the cell morphology and growth.Acridine orange dyeing was used to observe the proliferation of cell in collagen sponge at 20 and 35 days of culture.Hematoxylin-eosin staining was used to observe the growth of cells in collagen sponge at 65 days of culture.RESULTS:The cells of positive control group were not adhesive and all died three days later.Those of collagen sponge group and negative control group were normal and adhesive.With the prolong of culture time,the sponge pore decreased gradually,sponge appearance became eminent and transparent,the cell increased in number but decreased in morphology.Acridine orange dyeing at 20 and 35 days of culture showed that a large amount of cells appeared in the co-culture of collagen sponge with lamb kidney fibroblast,and pack of cell clumps grew.Abundant blue nuclei and newborn red collagen fiber were found by hematoxylin-eosin staining.CONCLUSION:The collagen sponge from newborn bovine skin has a good biocompatibility with lamb kidney fibroblast cell

  3. Significance of nano- and microtopography for cell-surface interactions in orthopaedic implants.

    Science.gov (United States)

    Jäger, M; Zilkens, C; Zanger, K; Krauspe, R

    2007-01-01

    Cell-surface interactions play a crucial role for biomaterial application in orthopaedics. It is evident that not only the chemical composition of solid substances influence cellular adherence, migration, proliferation and differentiation but also the surface topography of a biomaterial. The progressive application of nanostructured surfaces in medicine has gained increasing interest to improve the cytocompatibility and osteointegration of orthopaedic implants. Therefore, the understanding of cell-surface interactions is of major interest for these substances. In this review, we elucidate the principle mechanisms of nano- and microscale cell-surface interactions in vitro for different cell types onto typical orthopaedic biomaterials such as titanium (Ti), cobalt-chrome-molybdenum (CoCrMo) alloys, stainless steel (SS), as well as synthetic polymers (UHMWPE, XLPE, PEEK, PLLA). In addition, effects of nano- and microscaled particles and their significance in orthopaedics were reviewed. The significance for the cytocompatibility of nanobiomaterials is discussed critically.

  4. Highly Fluorescent and Photostable Polymeric Nanofibers as Scaffolds for Cell Interfacing and Long-Term Tracking.

    Science.gov (United States)

    Diao, Hua Jia; Wang, Kai; Long, Hong Yan; Wang, Mingfeng; Chew, Sing Yan

    2016-03-09

    Highly fluorescent polymeric nanofibers fabricated via electrospinning of PCL-DPP-PCL (photostable polycaprolactones-di(thiophene-2-yl)-diketopyrrolopyrrole-photostable polycaprolactones) and commercial PCL mixture show superior photostability and cytocompatibility for long-term tracking of cell-substrate interaction. As a proof of concept, these PCL-DPP-PCL nanofibers enable clear visualization of intricate cell-substrate interactions such as oligodendrocyte myelination.

  5. Mesenchymal stem cell interaction with ultra smooth nanostructured diamond for wear resistant orthopaedic implants

    OpenAIRE

    Clem, William C.; Chowdhury, Shafiul; Catledge, Shane A.; Weimer, Jeffrey J.; Shaikh, Faheem M; Hennessy, Kristin M; Konovalov, Valery V.; Hill, Michael R; Waterfeld, Alfred; Bellis, Susan L.; Vohra, Yogesh K.

    2008-01-01

    Ultra smooth nanostructured diamond (USND) can be applied to greatly increase the wear resistance of orthopaedic implants over conventional designs. Herein we describe surface modification techniques and cytocompatibility studies performed on this new material. We report that hydrogen (H) -terminated USND surfaces supported robust mesenchymal stem cell (MSC) adhesion and survival, while oxygen (O) and fluorine (F) -terminated surfaces resisted cell adhesion, indicating that USND can be modifi...

  6. Construction of physical crosslink-based chitosan/liquid crystal composite hydrogel and evaluation on their cytocompatibility

    Science.gov (United States)

    Du, Lin; Yang, Xiaohui; Li, Wenqiang; Luo, Xuhui; Wu, Hao; Zhang, Jiaqing; Tu, Mei

    2017-01-01

    In order to provide a novel biomimetic composite substrate for tissue engineering and explore the interaction between cells and this type of material, we developed chitosan/liquid crystal (CS/LC) composite hydrogel with embedded LC phases by composing of cholesterol hydroxypropyl cellulose ester liquid crystalline material and CS. The micromorphology of CS/LC composite hydrogels exhibited ‘islands-sea’ phase separation structures similar to the ‘fluid mosaic model’ of biomembrane. In vitro cell compatibility study suggested that 3T3 is fibroblasts exhibited better initial cell adhesions and higher proliferation rates on the composite hydrogel than on the polystyrene control plate and the pure LC membrane. This novel CS/LC composite hydrogel provides more favorable interface for cell growth and proliferation and may serve as potentially active substrate for engineering interfaces to live cells. PMID:28149528

  7. Influence of biocompatible metal ions (Ag, Fe, Y) on the surface chemistry, corrosion behavior and cytocompatibility of Mg-1Ca alloy treated with MEVVA.

    Science.gov (United States)

    Liu, Yang; Bian, Dong; Wu, Yuanhao; Li, Nan; Qiu, Kejin; Zheng, Yufeng; Han, Yong

    2015-09-01

    Mg-1Ca samples were implanted with biocompatible alloy ions Ag, Fe and Y respectively with a dose of 2×10(17)ionscm(-2) by metal vapor vacuum arc technique (MEVVA). The surface morphologies and surface chemistry were investigated by SEM, AES and XPS. Surface changes were observed after all three kinds of elemental ion implantation. The results revealed that the modified layer was composed of two sublayers, including an outer oxidized layer with mixture of oxides and an inner implanted layer, after Ag and Fe ion implantation. Y ion implantation induced an Mg/Ca-deficient outer oxidized layer and the distribution of Y along with depth was more homogeneous. Both electrochemical test and immersion test revealed accelerated corrosion rate of Ag-implanted Mg-1Ca and Fe-implanted Mg-1Ca, whereas Y ion implantation showed a short period of protection since enhanced corrosion resistance was obtained by electrochemical test, but accelerated corrosion rate was found by long period immersion test. Indirect cytotoxicity assay indicated good cytocompatibility of Y-implanted Mg-1Ca. Moreover, the corresponding corrosion mechanisms involving implanting ions into magnesium alloys were proposed, which might provide guidance for further application of plasma ion implantation to biodegradable Mg alloys.

  8. Preliminarily study of a novel porous composite: cytocompatibility in vitro and osteogenesis in vivo%多孔复合材料PHBV-SGBG的体外细胞相容性和体内成骨性

    Institute of Scientific and Technical Information of China (English)

    唐倩; 陈建洪; 吴坚; 王萍; 彭助力; 梁焕友; 陈晓峰; 吴刚

    2010-01-01

    目的 研究新型复合材料3-羟基丁酸-co-3-羟基戊酸共聚物-溶胶-凝胶生物活性玻璃(PHBV-SGBG)对骨髓基质细胞的细胞相容性,并建立动物骨缺损模型,探讨PHBV-SGBG的体内成骨效能.方法 采用MTT法和直接接触法检测复合材料PHBV-SGBG的细胞相容性.制备犬胫骨骨缺损模型,实验组在骨缺损区植入PHBV-SGBG材料,对照组不作处理,分别于术后2、4、8、12周取材,扫描电镜和X线能谱分析观察该材料的体内成骨效能.结果 复合材料PHBV-SGBG的细胞毒性分级在0~1之间,骨髓基质细胞可紧密附着于材料表面,黏附、生长、增殖,并有突起向材料的连通微孔内伸展.实验组术后2周已有明显新骨生成,术后4周时Ca/P元素比值(1.086±0.034),对照组为(0.793±0.053),术后12周时骨缺损区充填新生的成熟骨组织,扫描电镜和能谱分析显示实验组Ca峰值逐渐升高:12周时Ca/P元素比值(1.603±0.067),优于对照组(11456±0.036)(P<0.05).结论 复合材料PHBV-SGBG无细胞毒性,具有很好的骨传导性和骨再生能力,有望成为新型的骨组织工程材料.%Objective To study the cytocompatibility of poly (3-hydroxybutyrate-co-3 -hydroxyvalerate)/sol-gel bioactive glass (PHBV/SGBG)composite with bone marrow stromal cells in vitro, and the in vivo osteogenesis efficiency of PHBV/SGBG composite under periosteal flap in bone defect animal models. Methods The cytocompatibility of PHBV/SGBG composite was tested by MTT assay and direct contact assay. Of established tibial defect canine models, PHBV/SGBG composite was embedded into the defects of the experimental group, while no treatment was given to the control group. Samples were harvested at weeks 2,4, 8, and 12 post-surgery. The effect of osteogenesis was inspected by scanning electron microscope observation and energy-dispersive X-ray analysis. Results The cytotoxicity score of PHBV/SGBG composite in the serial dilution extract and different culture

  9. Microstructure, corrosion resistance and cytocompatibility of Mg-5Y-4Rare Earth-0.5Zr (WE54) alloy

    Energy Technology Data Exchange (ETDEWEB)

    Smola, Bohumil, E-mail: bohumil.smola@mff.cuni.cz [Charles University Prague, Faculty of Mathematics and Physics, Ke Karlovu 5, 121 16 Praha 2 (Czech Republic); Joska, Ludek [Institute of Chemical Technology Prague, Faculty of Chemical Technology, Technicka 5, 166 28 Praha 6 (Czech Republic); Brezina, Vitezslav [University of South Bohemia, Institute of Physical Biology, Zamek 136, 373 33 Nove Hrady (Czech Republic); Stulikova, Ivana [Charles University Prague, Faculty of Mathematics and Physics, Ke Karlovu 5, 121 16 Praha 2 (Czech Republic); Hnilica, Frantisek [Czech Technical University in Prague, Faculty of Mechanical Engineering, Karlovo namesti 13, 121 35 Praha 2 (Czech Republic)

    2012-05-01

    Conventionally cast Mg-5Y-4Rare Earth-0.5Zr alloy (WE54) was solution treated (525 Degree-Sign C/8 h - T4) and one part subsequently aged (200 Degree-Sign C/16 h - T6). Powder from the cast WE54 alloy prepared by gas atomizing was consolidated by extrusion at 250 Degree-Sign C or 400 Degree-Sign C. Dense triangular arrangement of prismatic plates of transient D0{sub 19} and C-base centered orthorhombic phases precipitated in the {alpha}-Mg matrix during the T6 treatment. Both alloys prepared by powder metallurgy exhibit similar microstructure consisting of {approx} 4-6 {mu}m {alpha}-Mg matrix fibers surrounded by particles of the equilibrium Mg{sub 5}(Y, Nd) phase and of oxides. Open circuit potential and polarization resistance in the isotonic saline (9 g/l NaCl/H{sub 2}O) were monitored for 24 h. The corrosion rate of the T4 and T6 treated alloys was about 80 times lower than that of commercial Mg. Both alloys prepared by powder metallurgy exhibited approximately 8 times higher corrosion resistance than commercial Mg. The human MG-63 osteoblast-like cells spreading and division in the extracts (0.28 g in 28 ml of EMEM) of all 4 alloys were monitored by cinemicrography for 24 h. The MG-63 cells proliferate without cytotoxicity in all extracts. - Highlights: Black-Right-Pointing-Pointer T6 treated WE54 alloy exhibit dense triangular arrangement of {beta} Double-Prime and {beta} Prime phase prismatic plates. Black-Right-Pointing-Pointer Microstructure of PM prepared WE54 alloy consists of {alpha}-Mg phase cells surrounded by {beta} phase particles. Black-Right-Pointing-Pointer PM produced WE54 corroded 10 times faster in physiological solution thanT4 and T6 treated WE54. Black-Right-Pointing-Pointer MG63 cell spreading in EMEM extracts of PM prepared WE54 is comparable to that in control EMEM. Black-Right-Pointing-Pointer Cell mitosis is enhanced in PM WE54 extracts compared to the control and extracts of T4 and T6 WE54.

  10. Enhancement of interaction of L-929 cells with functionalized graphene via COOH+ ion implantation vs. chemical method

    Science.gov (United States)

    Zhao, Meng-Li; Liu, Xiao-Qi; Cao, Ye; Li, Xi-Fei; Li, De-Jun; Sun, Xue-Liang; Gu, Han-Qing; Wan, Rong-Xin

    2016-11-01

    Low hydrophilicity of graphene is one of the major obstacles for biomaterials application. To create some hydrophilic groups on graphene is addressed this issue. Herein, COOH+ ion implantation modified graphene (COOH+/graphene) and COOH functionalized graphene were designed by physical ion implantation and chemical methods, respectively. The structure and surface properties of COOH+/graphene and COOH functionalized graphene were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), and contact angle measurement. Compared with graphene, COOH+/graphene and COOH functionalized graphene revealed improvement of cytocompatibility, including in vitro cell viability and morphology. More importantly, COOH+/graphene exhibited better improvement effects than functionalized graphene. For instance, COOH+/graphene with 1 × 1018 ions/cm2 showed the best cell-viability, proliferation and stretching. This study demonstrated that ion implantation can better improve the cytocompatibility of the graphene.

  11. Hepatic Bel-7402 Cell Proliferation on Different Phospholipid Surfaces

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Phospholipids are believed to be important biomaterials.However, limited information is available on their cytocompatibilities.The objective of this study is to evaluate the effects of different phospholipids on the proliferation of hepatic Bel-7402 cells by comparing the adhesion, viability and proliferation of Bel-7402 cells cultured on different phospholipid surfaces.The cell adhesion, determined by counting the number of adhered cells to the surface, indicated that the cell adhesion was enhanced on charged phospolipid membranes.The cell viability evaluated by MTT[3 (4,5-dimethylthiazole-2-yl)-2,5-diphenyl tetrazolium-bromide] showed that cells cultured on charged phospholipids have greater viability than those cultured on the control, while cells cultured on neutral phospholipids showed lower viability.The cell cycle analysis using flow cytometry demonstrated that S phase entry increased on charged phospholipids, while S phase entry decreased on neutral phospholipids.The results suggested that charged phospholipids, especially positively charged phospholipids, show better cytocompatibilities than neutral phospholipids to hepatic Bel-7402 cell.

  12. Evaluation for cell affinity of the composite material containing carbon nanotubes

    Institute of Scientific and Technical Information of China (English)

    KANG Shizhao; WAN Yuqing; YAN Huijuan; BEI Jianzhong; WANG Chen; WANG Shenguo; WANG Chunru; WAN Lijun; BAI Chunli

    2004-01-01

    The composite material of poly-(L-lactide) (PLLA) and carbon nanotubes (CNTs) were prepared. Its surface morphologies and property were worked out by using atomic force microscopy (AFM) and contact angle measurement. Moreover, the prime cytocompatibility was used to investigate the biocompatibility of the composite material containing CNTs and the effects of CNTs on one aspect of cell function, cell affinity. The results obtained indicate that the composite material of PLLA and CNTs possesses good biocompatibility for both the 3T3 fibroblasts and Oct-1 osteoblast-like cells. The addition of CNTs will greatly affect cell affinity of the material, which may be disadvantage for the cell adhesion.

  13. Photoclick Hydrogels Prepared from Functionalized Cyclodextrin and Poly(ethylene glycol) for Drug Delivery and in Situ Cell Encapsulation.

    Science.gov (United States)

    Shih, Han; Lin, Chien-Chi

    2015-07-13

    Polymers or hydrogels containing modified cyclodextrin (CD) are highly useful in drug delivery applications, as CD is a cytocompatible amphiphilic molecule that can complex with a variety of hydrophobic drugs. Here, we designed modular photoclick thiol-ene hydrogels from derivatives of βCD and poly(ethylene glycol) (PEG), including βCD-allylether (βCD-AE), βCD-thiol (βCD-SH), PEG-thiol (PEGSH), and PEG-norbornene (PEGNB). Two types of CD-PEG hybrid hydrogels were prepared using radical-mediated thiol-ene photoclick reactions. Specifically, thiol-allylether hydrogels were formed by reacting multiarm PEGSH and βCD-AE, and thiol-norbornene hydrogels were formed by cross-linking βCD-SH and multiarm PEGNB. We characterized the properties of these two types of thiol-ene hydrogels, including gelation kinetics, gel fractions, hydrolytic stability, and cytocompatibility. Compared with thiol-allylether hydrogels, thiol-norbornene photoclick reaction formed hydrogels with faster gelation kinetics at equivalent macromer contents. Using curcumin, an anti-inflammatory and anticancer hydrophobic molecule, we demonstrated that CD-cross-linked PEG-based hydrogels, when compared with pure PEG-based hydrogels, afforded higher drug loading efficiency and prolonged delivery in vitro. Cytocompatibility of these CD-cross-linked hydrogels were evaluated by in situ encapsulation of radical sensitive pancreatic MIN6 β-cells. All formulations and cross-linking conditions tested were cytocompatible for cell encapsulation. Furthermore, hydrogels cross-linked by βCD-SH showed enhanced cell proliferation and insulin secretion as compared to gels cross-linked by either dithiothreitol (DTT) or βCD-AE, suggesting the profound impact of both macromer compositions and gelation chemistry on cell fate in chemically cross-linked hydrogels.

  14. Synthesis of an AlE-active fluorogen and its application in cell imaging

    Institute of Scientific and Technical Information of China (English)

    YU Yong; HONG YuNing; FENG Chao; LIU JianZhao; LAM Jacky Wing Yip; FAISAL Mahtab; NG Ka Ming; LUO Kathy Qian; TANG Ben Zhong

    2009-01-01

    A fluorogen named 1-decyl-1-methyl-2,5-bis{4-[(N,N-diethylamino)methyl]phenyl}-3,4-diphenylsilole (3) was synthesized. It emitted weakly as isolated molecule but strongly as supramolecular aggregate, showing a characteristic behavior of aggregation-induced emission (ALE). The molecules of 3 formed highly emissive nanoparticles in aqueous media, which quickly and selectively marked cytoplasm of HeLa cells and posed no toxicity to the living cells. The fluorogen is thus a promising candidate mate-rial for cell imaging as a sensitive, selective and cytocompatible biosensor.

  15. Synthesis of an AIE-active fluorogen and its application in cell imaging

    Institute of Scientific and Technical Information of China (English)

    LAM; Jacky; Wing; Yip; FAISAL; Mahtab; NG; Ka; Ming; LUO; Kathy; Qian

    2009-01-01

    A fluorogen named 1-decyl-1-methyl-2,5-bis{4-[(N,N-diethylamino)methyl]phenyl}-3,4-diphenylsilole (3) was synthesized. It emitted weakly as isolated molecule but strongly as supramolecular aggregate, showing a characteristic behavior of aggregation-induced emission (AIE). The molecules of 3 formed highly emissive nanoparticles in aqueous media, which quickly and selectively marked cytoplasm of HeLa cells and posed no toxicity to the living cells. The fluorogen is thus a promising candidate mate-rial for cell imaging as a sensitive, selective and cytocompatible biosensor.

  16. Effect of polytetrafluoroethylene artificial blood vessels on platelet aggregation and its cytocompatibility%聚四氟乙烯人工血管对血小板聚集的影响及细胞相容性

    Institute of Scientific and Technical Information of China (English)

    姜正明; 陈魁; 胡彩娜

    2016-01-01

    背景:聚四氟乙烯人工血管是临床常用的医用材料,但其具体的基础研究内容尚未完善。目的:观察聚四氟乙烯人工血管对血小板聚集的作用及细胞相容性。方法:①对血小板聚集的作用:检测聚四氟乙烯人工血管的凝血时间、复钙时间。将生理盐水、蒸馏水及聚四氟乙烯人工血管分别加入兔红细胞悬液中,计算溶血率;②细胞生物相容性:将SD大鼠原代心肌细胞分别接种于普通玻璃爬片与聚四氟乙烯人工血管片上,3 d后,检测细胞乳酸脱氢酶释放;5 d后,检测细胞增殖。结果与结论:①聚四氟乙烯人工血管对兔血的动态凝血时间、复钙时间没有影响;聚四氟乙烯人工血管的溶血率为2.3%;②与接种于普通玻璃爬片上的心肌细胞相比,接种于聚四氟乙烯人工血管片上的心肌细胞增殖及乳酸脱氢酶释放无明显变化;③结果表明,聚四氟乙烯人工血管血小板聚集无影响,具有良好的血液相容性与细胞相容性。%BACKGROUND:Polytetrafluoroethylene artificial blood vessels have been extensively used in clinic. However, there is stil a lack of basic study on it. OBJECTIVE:To observe the effect of polytetrafluoroethylene artificial blood vessels on platelet aggregation and its cytocompatibility. METHODS:Effect on platelet aggregation:Dynamic platelet clotting time and plasma recalcification time were detected. Normal saline, distil ed water and polytetrafluoroethylene artificial blood vessels were added into the rabbit red cel suspensions, respectively, to count the hemolysis ratio. Cytocompatibility:Primary myocardial cel s from Sprague-Dawley rats were respectively seeded onto the common round coverslip and polytetrafluoroethylene artificial blood vessels, and the lactate deshydrogenase release and cel proliferation were detected at 3 and 5 days, respectively. RESULTS AND CONCLUSION:Polytetrafluoroethylene artificial

  17. PEG hydrogels formed by thiol-ene photo-click chemistry and their effect on the formation and recovery of insulin-secreting cell spheroids.

    Science.gov (United States)

    Lin, Chien-Chi; Raza, Asad; Shih, Han

    2011-12-01

    Hydrogels provide three-dimensional frameworks with tissue-like elasticity and high permeability for culturing therapeutically relevant cells or tissues. While recent research efforts have created diverse macromer chemistry to form hydrogels, the mechanisms of hydrogel polymerization for in situ cell encapsulation remain limited. Hydrogels prepared from chain-growth photopolymerization of poly(ethylene glycol) diacrylate (PEGDA) are commonly used to encapsulate cells. However, free radical associated cell damage poses significant limitation for this gel platform. More recently, PEG hydrogels formed by thiol-ene photo-click chemistry have been developed for cell encapsulation. While both chain-growth and step-growth photopolymerizations offer spatial-temporal control over polymerization kinetics, step-growth thiol-ene hydrogels offer more diverse and preferential properties. Here, we report the superior properties of step-growth thiol-ene click hydrogels, including cytocompatibility of the reactions, improved hydrogel physical properties, and the ability for 3D culture of pancreatic β-cells. Cells encapsulated in thiol-ene hydrogels formed spherical clusters naturally and were retrieved via rapid chymotrypsin-mediated gel erosion. The recovered cell spheroids released insulin in response to glucose treatment, demonstrating the cytocompatibility of thiol-ene hydrogels and the enzymatic mechanism of cell spheroids recovery. Thiol-ene click reactions provide an attractive means to fabricate PEG hydrogels with superior gel properties for in situ cell encapsulation, as well as to generate and recover 3D cellular structures for regenerative medicine applications.

  18. Use of the methylcellulose gum for fat up-take absorption in coated products

    Directory of Open Access Journals (Sweden)

    Daniele Domingues Dill

    2008-08-01

    Full Text Available Even though coated meats have added value to products and gained consumers confidence, by improving these product’s appearance and taste, they go through a pre-frying stage during processing which releases the water and allows fat to enter the product, thus increasing fat content. The purpose of this work was to develop a coating system that absorbs less fat during the pre-frying stage of a chicken coated product. To do that, methylcellulose gum was added (MC in different concentrations in the covering systems, batter (coating liquid and breading (covering expresses. Five experiments were carried out, a standard experiment, without ingredient addition with technological function, formulations with addition of MC in the batter (0,5% and 2,0%, with addition of MC in the batter and in the breading (1% in each and with addition of MC in the breading (2,0%. Results showed that fat uptake reduction in formulations with 0,5 and 2,0% of MC in the batter were of 5,81% and 8,40%, respectively, and in experiments with 1% of MC in the batter and 1% of MC in the breading was of 7,66%. In experiments that received 2% of MC in the breading , fat uptake reduction was of 10,51%. Formulations with 2% of MC added to the breading (10,51% and 2% of MC added to the batter (8,40% presented the largest reductions in fat uptake during the pre-fried stage. Analysis of sensorial acceptance showed that all formulations had a superior acceptance index of 70%, with no significant difference among the other tested formulations acceptance results (p <0,05. These findings show the efficiency of MC as a fat uptake barrier during the pre-fried stage, increasing humidity content, and becoming an advantageous technological alternative for the food industry.

  19. Ractopamine up take by alfalfa (Medicago sativa) and wheat (Triticum aestivum) from soil.

    Science.gov (United States)

    Shelver, Weilin L; DeSutter, Thomas M

    2015-08-01

    Ractopamine is a beta adrenergic agonist used as a growth promoter in swine, cattle and turkeys. To test whether ractopamine has the potential to accumulate in plants grown in contaminated soil, a greenhouse study was conducted with alfalfa (Medicago sativa) and wheat (Triticum aestivum) grown in two soils having different concentrations of organic matter (1.3% and 2.1%), amended with 0, 0.5, and 10 μg/g of ractopamine. Plant growth ranged from 2.7 to 8.8 g dry weight (dw) for alfalfa, and 8.7 to 40 g dw for wheat and was generally greater in the higher organic matter content soil. The uptake of ractopamine in plant tissues ranged from non-detectable to 897 ng/g and was strongly dependent on soil ractopamine concentration across soil and plant tissue. When adjusted to the total fortified quantities, the amount of ractopamine taken up by the plant tissue was low, <0.01% for either soil.

  20. Biocorrosion behavior and cell viability of adhesive polymer coated magnesium based alloys for medical implants

    Energy Technology Data Exchange (ETDEWEB)

    Abdal-hay, Abdalla [Departmentt of Bionano System Engineering, College of Engineering, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Department of Mechanical Design Engineering, Advanced wind power system research institute, Chonbuk National University, Jeonju 561-756 (Korea, Republic of); Dewidar, Montasser [Department of Materials and Mechanical Design, Faculty of Energy Engineering, South Valley University, Aswan (Egypt); Lim, Jae Kyoo, E-mail: jklim@jbnu.ac.kr [Department of Mechanical Design Engineering, Advanced wind power system research institute, Chonbuk National University, Jeonju 561-756 (Korea, Republic of)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer The corrosion behavior of magnesium for orthopedic applications is extremely poor. Black-Right-Pointing-Pointer The solvent (DCM, THF and DMF) had a strong effect on the coatings performance. Black-Right-Pointing-Pointer Mg bar alloy coated with PVAc/DCM layers provided an excellent bonding strength. Black-Right-Pointing-Pointer Treated samples indicated significant damping for the degradation rate. Black-Right-Pointing-Pointer Cytocompatibility on MC3T3 cells of the PVAc/DCM samples revealed a good behavior. - Abstract: The present study was ultimately aimed to design novel adhesive biodegradable polymer, poly(vinyl acetate) (PVAc), coatings onto Mg based alloys by the dip-coating technique in order to control the degradation rate and enhance the biocompatibility of magnesium alloys. The influence of various solvents on PVAc surface topography and their protection of Mg alloys were dramatically studied in vitro. Electrochemical polarization, degradation, and PVAc film cytocompatibility were also tested. Our results showed that the solvent had a significant effect on coating quality. PVAc/dichloromethane solution showed a porous structure and solution concentration could control the porous size. The coatings prepared using tetrahydrofuran and dimethylformamide solvents are exceptional in their ability to generate porous morphology even at low polymer concentration. In general, the corrosion performance appears to be different on different PVAc-solvent system. Immersion tests illustrated that the porous morphology on PVAc stabilized corrosion rates. A uniform corrosion attack in artificial simulation body fluid was also exhibited. The cytocompatibility of osteoblast cells (MC3T3) revealed high adherence, proliferation, and survival on the porous structure of PVAc coated Mg alloy, which was not observed for the uncoated samples. This novel PVAc coating is a promising candidate for biodegradable implant materials, which might

  1. Cell proliferation, viability, and in vitro differentiation of equine mesenchymal stem cells seeded on bacterial cellulose hydrogel scaffolds

    Energy Technology Data Exchange (ETDEWEB)

    Favi, Pelagie M.; Benson, Roberto S. [Department of Materials Science and Engineering, College of Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Neilsen, Nancy R. [Department of Biomedical and Diagnostic Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996 (United States); Hammonds, Ryan L. [Department of Materials Science and Engineering, College of Engineering, University of Tennessee, Knoxville, TN 37996 (United States); Bates, Cassandra C. [Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996 (United States); Stephens, Christopher P. [Department of Surgery, Graduate School of Medicine, University of Tennessee, Knoxville, TN 37996 (United States); Center for Materials Processing, University of Tennessee, Knoxville, TN 37996 (United States); Dhar, Madhu S., E-mail: mdhar@utk.edu [Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN 37996 (United States)

    2013-05-01

    The culture of multipotent mesenchymal stem cells on natural biopolymers holds great promise for treatments of connective tissue disorders such as osteoarthritis. The safety and performance of such therapies relies on the systematic in vitro evaluation of the developed stem cell-biomaterial constructs prior to in vivo implantation. This study evaluates bacterial cellulose (BC), a biocompatible natural polymer, as a scaffold for equine-derived bone marrow mesenchymal stem cells (EqMSCs) for application in bone and cartilage tissue engineering. An equine model was chosen due to similarities in size, load and types of joint injuries suffered by horses and humans. Lyophilized and critical point dried BC hydrogel scaffolds were characterized using scanning electron microscopy (SEM) to confirm nanostructure morphology which demonstrated that critical point drying induces fibre bundling unlike lyophilisation. EqMSCs positively expressed the undifferentiated pluripotent mesenchymal stem cell surface markers CD44 and CD90. The BC scaffolds were shown to be cytocompatible, supporting cellular adhesion and proliferation, and allowed for osteogenic and chondrogenic differentiation of EqMSCs. The cells seeded on the BC hydrogel were shown to be viable and metabolically active. These findings demonstrate that the combination of a BC hydrogel and EqMSCs are promising constructs for musculoskeletal tissue engineering applications. - Highlights: ► Critical point drying induces fibre bundling unlike lyophilisation. ► Cells positively expressed undifferentiated pluripotent stem cell markers. ► BCs were cytocompatible, supported cell adhesion, proliferation and differentiation ► Cells seeded on BC scaffolds were viable and metabolically active. ► Findings demonstrate that BC and EqMSCs are promising tissue engineered constructs.

  2. 3D patterned stem cell differentiation using thermo-responsive methylcellulose hydrogel molds

    Science.gov (United States)

    Lee, Wonjae; Park, Jon

    2016-07-01

    Tissue-specific patterned stem cell differentiation serves as the basis for the development, remodeling, and regeneration of the multicellular structure of the native tissues. We herein proposed a cytocompatible 3D casting process to recapitulate this patterned stem cell differentiation for reconstructing multicellular tissues in vitro. We first reconstituted the 2D culture conditions for stem cell fate control within 3D hydrogel by incorporating the sets of the diffusible signal molecules delivered through drug-releasing microparticles. Then, utilizing thermo-responsivity of methylcellulose (MC), we developed a cytocompatible casting process to mold these hydrogels into specific 3D configurations, generating the targeted spatial gradients of diffusible signal molecules. The liquid phase of the MC solution was viscous enough to adopt the shapes of 3D impression patterns, while the gelated MC served as a reliable mold for patterning the hydrogel prepolymers. When these patterned hydrogels were integrated together, the stem cells in each hydrogel distinctly differentiated toward individually defined fates, resulting in the formation of the multicellular tissue structure bearing the very structural integrity and characteristics as seen in vascularized bones and osteochondral tissues.

  3. Long-term stem cell labeling by collagen-functionalized single-walled carbon nanotubes

    Science.gov (United States)

    Mao, Hongli; Cai, Rong; Kawazoe, Naoki; Chen, Guoping

    2014-01-01

    The monitoring of grafted stem cells is crucial to assess the efficiency, effectiveness and safety of such stem cell-based therapies. In this regard, a reliable and cytocompatible labeling method for stem cells is critically needed. In this study, the collagen-functionalized single-walled carbon nanotubes (Col-SWCNTs) were used as imaging probes for labeling of human mesenchymal stem cells (hMSCs) and the inherent Raman scattering of SWCNTs was used to image the SWCNT-labeled cells. The results showed that the Col-SWCNTs exhibit efficient cellular internalization by hMSCs without affecting their proliferation and differentiation. The prolonged dwell time of Col-SWCNTs in cells ensured the long-term labeling for up to 2 weeks. This work reveals the potential of Col-SWCNTs as probes for long-term stem cell labeling.

  4. Intelligent thermoresponsive substrate from modified overhead projection sheet as a tool for construction and support of cell sheets in vitro.

    Science.gov (United States)

    Nithya, Joseph; Kumar, P R Anil; Tilak, Prasad; Leena, Joseph; Sreenivasan, K; Kumary, T V

    2011-02-01

    Cell sheet engineering using thermoresponsive culture dishes allows harvesting of intact in vitro cell sheet. In this study, commercially available polyethylene terephthalate-based overhead projection transparency sheet (OHPS) was identified as a substrate for coating thermoresponsive poly(N-isopropylacrylamide-co-glycidylmethacrylate) (NGMA) copolymer having lower critical solution temperature of 28°C. Since OHPS is highly hydrophobic and rigid, the surface was modified by alkali treatment (OHPS-M) to functionalize the surface with carboxyl and hydroxyl groups so as to make it more suitable for efficient coating of NGMA copolymer and cell culture. To impart thermoresponsiveness, OHPS-M was coated with NGMA (OHPS-MC). Surface morphology, surface chemistry, and thermoresponsive coating were analyzed by profilometry, scanning electron microscopy, water contact angle, and Fourier transform infrared spectroscopy. The cytotoxicity, cell adhesion, and proliferation on OHPS-M and OHPS-MC were analyzed using L929 cells. Specific cytocompatibility analysis was done using SIRC (Rabbit corneal) cells. Data revealed cytocompatible nature of OHPS-M and OHPS-MC. Suitability of OHPS-MC for cell sheet harvest and transfer efficiency was assessed using primary corneal cells. Corneal cell sheet constructs retrieved by temperature variation was characterized by reverse transcriptase polymerase chain reaction for markers specific to differentiated corneal cells (keratin 3 and keratin 12) and proliferating cell nuclear antigen, and assessed for viability using fluorescein diacetate staining, tissue architecture by scanning electron microscopy, and cell-cell contacts by connexin-43 staining. The retrieved cell sheets retained corneal epithelial characteristics such as keratin 3/12, viability, and tissue architecture with intact cell-cell contacts as in native tissue. The results proved that surface modification and coating with NGMA on OHPS offer a novel biocompatible thermosensitive

  5. Cell surface engineering with edible protein nanoshells.

    Science.gov (United States)

    Drachuk, Irina; Shchepelina, Olga; Harbaugh, Svetlana; Kelley-Loughnane, Nancy; Stone, Morley; Tsukruk, Vladimir V

    2013-09-23

    Natural protein (silk fibroin) nanoshells are assembled on the surface of Saccharomyces cerevisiae yeast cells without compromising their viability. The nanoshells facilitate initial protection of the cells and allow them to function in encapsulated state for some time period, afterwards being completely biodegraded and consumed by the cells. In contrast to a traditional methanol treatment, the gentle ionic treatment suggested here stabilizes the shell silk fibroin structure but does not compromise the viability of the cells, as indicated by the fast response of the encapsulated cells, with an immediate activation by the inducer molecules. Extremely high viability rates (up to 97%) and preserved activity of encapsulated cells are facilitated by cytocompatibility of the natural proteins and the formation of highly porous shells in contrast to traditional polyelectrolyte-based materials. Moreover, in a high contrast to traditional synthetic shells, the silk proteins are biodegradable and can be consumed by cells at a later stage of growth, thus releasing the cells from their temporary protective capsules. These on-demand encapsulated cells can be considered a valuable platform for biocompatible and biodegradable cell encapsulation, controlled cell protection in a synthetic environment, transfer to a device environment, and cell implantation followed by biodegradation and consumption of protective protein shells.

  6. Fabrication and cyto-compatibility of Fe3O4/SiO2/graphene-CdTe QDs/CS nanocomposites for drug delivery.

    Science.gov (United States)

    Ou, Jun; Wang, Fang; Huang, Yuanjie; Li, Duosheng; Jiang, Yuming; Qin, Qing-Hua; Stachurski, Z H; Tricoli, Antonio; Zhang, Tina

    2014-05-01

    Synthesis of magnetic Fe3O4/SiO2/graphene-CdTe QDs/chitosan nanocomposites (FGQCs) is investigated with respect to their potential of improving the drug loading content above that of magnetic/fluorescent bifunctional nanocomposites. To evaluate the performance of the FGQCs, their surface morphology was thoroughly assessed. The in vitro interaction between the FGQCs and heptoma cell line smmc-7721 cells was observed for the first time by TEM ultrathin section imaging. At an excitation wavelength of 365 nm, the graphene-QDs exhibit a strong luminescence in aqueous environments. The loading content and entrapment efficiency of the FGQCs were 70% and 50%, respectively. The cytotoxicity of this novel drug delivery system was evaluated in vitro using heptoma cell line smmc-7721 and quantified by the 3-(4,5-dimethylthiazol-z-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The results show that FGQCs are a promising new multifunctional material for drug delivery in biological and medical applications.

  7. Eu/Tb codoped spindle-shaped fluorinated hydroxyapatite nanoparticles for dual-color cell imaging.

    Science.gov (United States)

    Ma, Baojin; Zhang, Shan; Qiu, Jichuan; Li, Jianhua; Sang, Yuanhua; Xia, Haibing; Jiang, Huaidong; Claverie, Jerome; Liu, Hong

    2016-06-02

    Lanthanide doped fluorinated hydroxyapatite (FAp) nanoparticles are promising cell imaging nanomaterials but they are excited at wavelengths which do not match the light sources usually found in a commercial confocal laser scanning microscope (CLSM). In this work, we have successfully prepared spindle-shaped Eu/Tb codoped FAp nanoparticles by a hydrothermal method. Compared with single Eu doped FAp, Eu/Tb codoped FAp can be excited by a 488 nm laser, and exhibit both green and red light emission. By changing the amounts of Eu and Tb peaks, the emission in the green region (500-580 nm) can be decreased to the benefit of the emission in the red region (580-720 nm), thus reaching a balanced dual color emission. Using MC3T3-E1 cells co-cultured with Eu/Tb codoped FAp nanoparticles, it is observed that the nanoparticles are cytocompatible even at a concentration as high as 800 μg ml(-1). The Eu/Tb codoped FAp nanoparticles are located in the cytoplasm and can be monitored by dual color-green and red imaging with a single excitation light at 488 nm. At a concentration of 200 μg ml(-1), the cytoplasm is saturated in 8 hours, and Eu/Tb codoped FAp nanoparticles retain their fluorescence for at least 3 days. The cytocompatible Eu/Tb codoped FAp nanoparticles with unique dual color emission will be of great use for cell and tissue imaging.

  8. In vitro hemocompatibility and cytocompatibility of a three-layered vascular scaffold fabricated by sequential electrospinning of PCL, collagen, and PLLA nanofibers.

    Science.gov (United States)

    Haghjooy Javanmard, Shaghayegh; Anari, Jamal; Zargar Kharazi, Anousheh; Vatankhah, Elham

    2016-09-01

    Aiming to mimic a blood vessel structurally, morphologically, and mechanically, a sequential electrospinning technique using a small diameter mandrel collector was performed and a three-layered tubular scaffold composed of nanofibers of polycaprolactone, collagen, and poly(l-lactic acid) as inner, intermediate, and outer layers, respectively, was developed. Biological performances of the scaffold in terms of compatibility with blood and endothelial cells were assessed to get some insights into its potential use as a tissue engineered small-diameter vascular replacement compared to an expanded polytetrafluoroethylene vascular graft. Due to direct contact of the blood and endothelial cells with inner surface of the scaffold, polycaprolactone fibers were characterized using SEM, water contact angle measurement, and ATR-FTIR. Despite similar surface wettability of the electrospun scaffold and the expanded polytetrafluoroethylene graft, the three-layered scaffold significantly reduced platelet adhesion and hemolysis ratio compared to expanded polytetrafluoroethylene graft while comparable blood clotting profiles were observed for both electrospun scaffold and expanded polytetrafluoroethylene graft. However, inflammatory response to nanofibrous surface of the scaffold was reduced compared to expanded polytetrafluoroethylene graft. The electrospun scaffold also presented a significantly more supportive substrate for endothelialization than the expanded polytetrafluoroethylene graft. The results described herein suggested that the three-layered scaffold has superior biological properties compared to an expanded polytetrafluoroethylene graft for vascular tissue engineering.

  9. Biosynthesis of magnetic nanoparticles by human mesenchymal stem cells following transfection with the magnetotactic bacterial gene mms6.

    Science.gov (United States)

    Elfick, Alistair; Rischitor, Grigore; Mouras, Rabah; Azfer, Asim; Lungaro, Lisa; Uhlarz, Marc; Herrmannsdörfer, Thomas; Lucocq, John; Gamal, Wesam; Bagnaninchi, Pierre; Semple, Scott; Salter, Donald M

    2017-01-04

    The use of stem cells to support tissue repair is facilitated by loading of the therapeutic cells with magnetic nanoparticles (MNPs) enabling magnetic tracking and targeting. Current methods for magnetizing cells use artificial MNPs and have disadvantages of variable uptake, cellular cytotoxicity and loss of nanoparticles on cell division. Here we demonstrate a transgenic approach to magnetize human mesenchymal stem cells (MSCs). MSCs are genetically modified by transfection with the mms6 gene derived from Magnetospirillum magneticum AMB-1, a magnetotactic bacterium that synthesises single-magnetic domain crystals which are incorporated into magnetosomes. Following transfection of MSCs with the mms6 gene there is bio-assimilated synthesis of intracytoplasmic magnetic nanoparticles which can be imaged by MR and which have no deleterious effects on cell proliferation, migration or differentiation. The assimilation of magnetic nanoparticle synthesis into mammalian cells creates a real and compelling, cytocompatible, alternative to exogenous administration of MNPs.

  10. Biosynthesis of magnetic nanoparticles by human mesenchymal stem cells following transfection with the magnetotactic bacterial gene mms6

    Science.gov (United States)

    Elfick, Alistair; Rischitor, Grigore; Mouras, Rabah; Azfer, Asim; Lungaro, Lisa; Uhlarz, Marc; Herrmannsdörfer, Thomas; Lucocq, John; Gamal, Wesam; Bagnaninchi, Pierre; Semple, Scott; Salter, Donald M

    2017-01-01

    The use of stem cells to support tissue repair is facilitated by loading of the therapeutic cells with magnetic nanoparticles (MNPs) enabling magnetic tracking and targeting. Current methods for magnetizing cells use artificial MNPs and have disadvantages of variable uptake, cellular cytotoxicity and loss of nanoparticles on cell division. Here we demonstrate a transgenic approach to magnetize human mesenchymal stem cells (MSCs). MSCs are genetically modified by transfection with the mms6 gene derived from Magnetospirillum magneticum AMB-1, a magnetotactic bacterium that synthesises single-magnetic domain crystals which are incorporated into magnetosomes. Following transfection of MSCs with the mms6 gene there is bio-assimilated synthesis of intracytoplasmic magnetic nanoparticles which can be imaged by MR and which have no deleterious effects on cell proliferation, migration or differentiation. The assimilation of magnetic nanoparticle synthesis into mammalian cells creates a real and compelling, cytocompatible, alternative to exogenous administration of MNPs. PMID:28051139

  11. An in vitro evaluation of the Ca/P ratio for the cytocompatibility of nano-to-micron particulate calcium phosphates for bone regeneration.

    Science.gov (United States)

    Liu, Huinan; Yazici, Hilal; Ergun, Celaletdin; Webster, Thomas J; Bermek, Hakan

    2008-09-01

    Calcium phosphate based bioceramics have been widely used for orthopedic applications due to their chemical similarity to natural bone. The Ca/P stoichiometry of calcium phosphates strongly influences their performance under biological conditions, which have not yet been fully elucidated to date. For this reason, the objective of this in vitro study was to understand the relationship between the Ca/P ratio of nano-to-micron particulate calcium phosphate substrates and their biological properties, such as osteoblast (bone-forming cell) viability, collagen production, alkaline phosphatase activity and nitric oxide (NO) production. A group of calcium phosphates with Ca/P ratios between 0.5 and 2.5 were obtained by intentionally adjusting the Ca/P stoichiometry of the initial reactants necessary for calcium phosphate precipitation. For samples with 0.5 and 0.75 Ca/P ratios, tricalcium phosphate (TCP) and Ca(2)P(2)O(7) phases were observed. In contrast, for samples with 1.0 and 1.33 Ca/P ratios, the only stable phase was TCP. For samples with a 1.5 Ca/P ratio, the TCP phase was dominant; however, small amounts of the hydroxyapatite (HA) phase started to appear. For samples with a 1.6 Ca/P ratio, the HA phase was dominant. Lastly, for samples with 2.0 and 2.5 Ca/P ratios, the CaO phase started to appear in the HA phase which was the dominant phase. Moreover, the average grain size and the average pore size decreased from micron-scale (e.g. 1370nm for a 0.5 Ca/P ratio) to nano-scale (e.g. 262nm for a 2.5 Ca/P ratio) with increasing Ca/P ratios. The porosity (%) of calcium phosphate substrates also decreased with increasing Ca/P ratios. Previous in vitro results demonstrated increased osteoblast adhesion on calcium phosphates with higher Ca/P ratios (up to 2.5). The present study showed that the collagen production by osteoblasts was similar between all the calcium phosphates but slightly lower with a 1.6 Ca/P ratio. Greater alkaline phosphatase activity by osteoblasts was

  12. A cytocompatible micro/nano-textured surface with Si-doped titania mesoporous arrays fabricated by a one-step anodization.

    Science.gov (United States)

    Liu, Huibing; Huang, Xiaobo; Yu, Hanwu; Yang, Xiaoning; Zhang, Xiangyu; Hang, Ruiqiang; Tang, Bin

    2017-04-01

    To mimic the hierarchical structure of bone tissues, a hybrid micro/nano-textured titanium surface with Si-doped TiO2 mesoporous arrays is fabricated by a one-step high current anodization (HCA). Specifically, the HCA is carried out in a electrolyte containing NO3(-) and SiO3(2-). The NO3(-) in the electrolyte is demonstrated to play a key role in mediating the formation of honeycombed TiO2 mesoporous arrays, which are different than the nanotubes formed by the mediating of F(-) ion in the conventional anodization. This unique structure endows the coating with improved mechanical properties compared to the nanotube layer. In addition, the Si is incorporated into the coating in a concentration-dependent manner. With the increase of Si doping amount in the coating, both the hydrophilic properties and surface free energy of coatings are obviously enhanced. The cell culture test shows that the osteoblast behaviors on this surface are positively influenced by the doped Si. Therefore, this micro/nano-textured surface coating doped with Si may endow the Ti-based implants long-term stability and good osseointegration.

  13. An artificial blood vessel implanted three-dimensional microsystem for modeling transvascular migration of tumor cells.

    Science.gov (United States)

    Wang, Xue-Ying; Pei, Ying; Xie, Min; Jin, Zi-He; Xiao, Ya-Shi; Wang, Yang; Zhang, Li-Na; Li, Yan; Huang, Wei-Hua

    2015-02-21

    Reproducing a tumor microenvironment consisting of blood vessels and tumor cells for modeling tumor invasion in vitro is particularly challenging. Here, we report an artificial blood vessel implanted 3D microfluidic system for reproducing transvascular migration of tumor cells. The transparent, porous and elastic artificial blood vessels are obtained by constructing polysaccharide cellulose-based microtubes using a chitosan sacrificial template, and possess excellent cytocompatibility, permeability, and mechanical characteristics. The artificial blood vessels are then fully implanted into the collagen matrix to reconstruct the 3D microsystem for modeling transvascular migration of tumor cells. Well-defined simulated vascular lumens were obtained by proliferation of the human umbilical vein endothelial cells (HUVECs) lining the artificial blood vessels, which enables us to reproduce structures and functions of blood vessels and replicate various hemodynamic parameters. Based on this model, the adhesion and transvascular migration of tumor cells across the artificial blood vessel have been well reproduced.

  14. A cytoprotective and degradable metal-polyphenol nanoshell for single-cell encapsulation.

    Science.gov (United States)

    Park, Ji Hun; Kim, Kyunghwan; Lee, Juno; Choi, Ji Yu; Hong, Daewha; Yang, Sung Ho; Caruso, Frank; Lee, Younghoon; Choi, Insung S

    2014-11-10

    Single-cell encapsulation promises the cytoprotection of the encased cells against lethal stressors, reminiscent of the sporulation process in nature. However, the development of a cytocompatible method for chemically mimicking the germination process (i.e., shell degradation on-demand) has been elusive, despite the shell degradation being pivotal for the practical use of functional cells as well as for single cell-based biology. We report that an artificial shell, composed of tannic acid (TA) and Fe(III) , on individual Saccharomyces cerevisiae controllably degrades on-demand, while protecting the yeast from multiple external aggressors, including UV-C irradiation, lytic enzymes, and silver nanoparticles. Cell division is suppressed by the TA-Fe(III) shell, but restored fully upon shell degradation. The formation of a TA-Fe(III) shell would provide a versatile tool for achieving the chemical version of "sporulation and germination".

  15. Engineered Hypopharynx from Coculture of Epithelial Cells and Fibroblasts Using Poly(ester urethane as Substratum

    Directory of Open Access Journals (Sweden)

    Zhisen Shen

    2013-01-01

    Full Text Available Porous polymeric scaffolds have been much investigated and applied in the field of tissue engineering research. Poly(ester urethane (PEU scaffolds, comprising pores of 1–20 μm in diameter on one surface and ≥200 μm on the opposite surface and in bulk, were fabricated using phase separation method for hypopharyngeal tissue engineering. The scaffolds were grafted with silk fibroin (SF generated from natural silkworm cocoon to enhance the scaffold’s hydrophilicity and further improve cytocompatibility to both primary epithelial cells (ECs and fibroblasts of human hypopharynx tissue. Coculture of ECs and fibroblasts was conducted on the SF-grafted PEU scaffold (PEU-SF to evaluate its in vitro cytocompatibility. After co-culture for 14 days, ECs were lined on the scaffold surface while fibroblasts were distributed in scaffold bulk. The results of in vivo investigation showed that PEU porous scaffold possessed good biocompatibility after it was grafted by silk fibroin. SF grafting improved the cell/tissue infiltration into scaffold bulk. Thus, PEU-SF porous scaffold is expected to be a good candidate to support the hypopharynx regeneration.

  16. Human mesenchymal stem cell behavior on segmented polyurethanes prepared with biologically active chain extenders.

    Science.gov (United States)

    Kavanaugh, Taylor E; Clark, Amy Y; Chan-Chan, Lerma H; Ramírez-Saldaña, Maricela; Vargas-Coronado, Rossana F; Cervantes-Uc, José M; Hernández-Sánchez, Fernando; García, Andrés J; Cauich-Rodríguez, Juan V

    2016-02-01

    The development of elastomeric, bioresorbable and biocompatible segmented polyurethanes (SPUs) for use in tissue-engineering applications has attracted considerable interest because of the existing need of mechanically tunable scaffolds for regeneration of different tissues, but the incorporation of osteoinductive molecules into SPUs has been limited. In this study, SPUs were synthesized from poly (ε-caprolactone)diol, 4,4'-methylene bis(cyclohexyl isocyanate) using biologically active compounds such as ascorbic acid, L-glutamine, β-glycerol phosphate, and dexamethasone as chain extenders. Fourier transform infrared spectroscopy (FTIR) revealed the formation of both urethanes and urea linkages while differential scanning calorimetry, dynamic mechanical analysis, X-ray diffraction and mechanical testing showed that these polyurethanes were semi-crystalline polymers exhibiting high deformations. Cytocompatibility studies showed that only SPUs containing β-glycerol phosphate supported human mesenchymal stem cell adhesion, growth, and osteogenic differentiation, rendering them potentially suitable for bone tissue regeneration, whereas other SPUs failed to support either cell growth or osteogenic differentiation, or both. This study demonstrates that modification of SPUs with osteogenic compounds can lead to new cytocompatible polymers for regenerative medicine applications.

  17. Collagen-IV supported embryoid bodies formation and differentiation from buffalo (Bubalus bubalis) embryonic stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Taru Sharma, G., E-mail: gts553@gmail.com [Reproductive Physiology Laboratory, Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243 122, Bareilly, U.P. (India); Dubey, Pawan K.; Verma, Om Prakash; Pratheesh, M.D.; Nath, Amar; Sai Kumar, G. [Reproductive Physiology Laboratory, Division of Physiology and Climatology, Indian Veterinary Research Institute, Izatnagar-243 122, Bareilly, U.P. (India)

    2012-08-03

    Graphical abstract: EBs formation, characterization and expression of germinal layers marker genes of in vivo developed teratoma using four different types of extracellular matrices. Highlights: Black-Right-Pointing-Pointer Collagen-IV matrix is found cytocompatible for EBs formation and differentiation. Black-Right-Pointing-Pointer Established 3D microenvironment for ES cells development and differentiation into three germ layers. Black-Right-Pointing-Pointer Collagen-IV may be useful as promising candidate for ES cells based therapeutic applications. -- Abstract: Embryoid bodies (EBs) are used as in vitro model to study early extraembryonic tissue formation and differentiation. In this study, a novel method using three dimensional extracellular matrices for in vitro generation of EBs from buffalo embryonic stem (ES) cells and its differentiation potential by teratoma formation was successfully established. In vitro derived inner cell masses (ICMs) of hatched buffalo blastocyst were cultured on buffalo fetal fibroblast feeder layer for primary cell colony formation. For generation of EBs, pluripotent ES cells were seeded onto four different types of extracellular matrices viz; collagen-IV, laminin, fibronectin and matrigel using undifferentiating ES cell culture medium. After 5 days of culture, ESCs gradually grew into aggregates and formed simple EBs having circular structures. Twenty-six days later, they formed cystic EBs over collagen matrix with higher EBs formation and greater proliferation rate as compared to other extracellular matrices. Studies involving histological observations, fluorescence microscopy and RT-PCR analysis of the in vivo developed teratoma revealed that presence of all the three germ layer derivatives viz. ectoderm (NCAM), mesoderm (Flk-1) and endoderm (AFP). In conclusion, the method described here demonstrates a simple and cost-effective way of generating EBs from buffalo ES cells. Collagen-IV matrix was found cytocompatible as it

  18. Physico-chemical properties of PDMS surfaces suitable as substrates for cell cultures

    Science.gov (United States)

    Raczkowska, Joanna; Prauzner-Bechcicki, Szymon; Lukes, Jaroslav; Sepitka, Josef; Bernasik, Andrzej; Awsiuk, Kamil; Paluszkiewicz, Czesława; Pabijan, Joanna; Lekka, Małgorzata; Budkowski, Andrzej

    2016-12-01

    Elastic properties of the substrate have profound effect on adhesion and proliferation of cells. Here, we introduce a method to produce polydimethylsiloxane (PDMS) substrates with stiffness tuned monotonically from 1.67 to 0.24 MPa, by the time of UV irradiation adjusted up to 5 h. The Young's modulus (determined by using nanoindenter) scales linearly with stiffness calculated using AFM-based force spectroscopy data. Such a relation enables the determination of the Young modulus from AFM force - distance curves also when the Herz model is not applicable. Our findings demonstrate that surface properties of PDMS substrates are not affected by the applied methodology of tuning substrate elasticity. Finally, the colorimetric proliferation assay (MTT) carried out for non-malignant (HCV29) and cancerous (T24) bladder cancer cells depicted a significant contribution of PDMS substrate elasticity to the behavior of cells. The softer PDMS substrate demonstrated excellent cytocompatibility whereas the stiff one is more cell-repellent.

  19. Calcification of MC3T3-E1 cells on titanium and zirconium.

    Science.gov (United States)

    Umezawa, Takayuki; Chen, Peng; Tsutsumi, Yusuke; Doi, Hisashi; Ashida, Maki; Suzuki, Shoichi; Moriyama, Keiji; Hanawa, Takao

    2015-01-01

    To confirm similarity of hard tissue compatibility between titanium and zirconium, calcification of MC3T3-E1 cells on titanium and zirconium was evaluated in this study. Mirror-polished titanium (Ti) and zirconium (Zr) disks and zirconium-sputter deposited titanium (Zr/Ti) were employed in this study. The surface of specimens were characterized using scanning electron microscopy and X-ray diffraction. Then, the cellular proliferation, differentiation and calcification of MC3T3-E1 cells on specimens were investigated. The surface of Zr/Ti was much smoother and cleaner than those of Ti and Zr. The proliferation of the cell was the same among three specimens, while the differentiation and calcification on Zr/Ti were faster than those on Ti and Zr. Therefore, Ti and Zr showed the identical hard tissue compatibility according to the evaluation with MC3T3-E1 cells. Sputter deposition may improve cytocompatibility.

  20. Biocorrosion behavior and cell viability of adhesive polymer coated magnesium based alloys for medical implants

    Science.gov (United States)

    Abdal-hay, Abdalla; Dewidar, Montasser; Lim, Jae Kyoo

    2012-11-01

    The present study was ultimately aimed to design novel adhesive biodegradable polymer, poly(vinyl acetate) (PVAc), coatings onto Mg based alloys by the dip-coating technique in order to control the degradation rate and enhance the biocompatibility of magnesium alloys. The influence of various solvents on PVAc surface topography and their protection of Mg alloys were dramatically studied in vitro. Electrochemical polarization, degradation, and PVAc film cytocompatibility were also tested. Our results showed that the solvent had a significant effect on coating quality. PVAc/dichloromethane solution showed a porous structure and solution concentration could control the porous size. The coatings prepared using tetrahydrofuran and dimethylformamide solvents are exceptional in their ability to generate porous morphology even at low polymer concentration. In general, the corrosion performance appears to be different on different PVAc-solvent system. Immersion tests illustrated that the porous morphology on PVAc stabilized corrosion rates. A uniform corrosion attack in artificial simulation body fluid was also exhibited. The cytocompatibility of osteoblast cells (MC3T3) revealed high adherence, proliferation, and survival on the porous structure of PVAc coated Mg alloy, which was not observed for the uncoated samples. This novel PVAc coating is a promising candidate for biodegradable implant materials, which might widen the use of Mg based implants.

  1. Nafion and modified-Nafion membranes for polymer electrolyte fuel cells: An overview

    Indian Academy of Sciences (India)

    A K Sahu; S Pitchumani; P Sridhar; A K Shukla

    2009-06-01

    Polymer electrolyte fuel cells (PEFCs) employ membrane electrolytes for proton transport during the cell reaction. The membrane forms a key component of the PEFC and its performance is controlled by several physical parameters, viz. water up-take, ion-exchange capacity, proton conductivity and humidity. The article presents an overview on Nafion membranes highlighting their merits and demerits with efforts on modified-Nafion membranes.

  2. Spontaneous Packaging and Hypothermic Storage of Mammalian Cells with a Cell-Membrane-Mimetic Polymer Hydrogel in a Microchip.

    Science.gov (United States)

    Xu, Yan; Mawatari, Kazuma; Konno, Tomohiro; Kitamori, Takehiko; Ishihara, Kazuhiko

    2015-10-21

    Currently, continuous culture/passage and cryopreservation are two major, well-established methods to provide cultivated mammalian cells for experiments in laboratories. Due to the lack of flexibility, however, both laboratory-oriented methods are unable to meet the need for rapidly growing cell-based applications, which require cell supply in a variety of occasions outside of laboratories. Herein, we report spontaneous packaging and hypothermic storage of mammalian cells under refrigerated (4 °C) and ambient conditions (25 °C) using a cell-membrane-mimetic methacryloyloxyethyl phosphorylcholine (MPC) polymer hydrogel incorporated within a glass microchip. Its capability for hypothermic storage of cells was comparatively evaluated over 16 days. The results reveal that the cytocompatible MPC polymer hydrogel, in combination with the microchip structure, enabled hypothermic storage of cells with quite high viability, high intracellular esterase activity, maintained cell membrane integrity, and small morphological change for more than 1 week at 4 °C and at least 4 days at 25 °C. Furthermore, the stored cells could be released from the hydrogel and exhibited the ability to adhere to a surface and achieve confluence under standard cell culture conditions. Both hypothermic storage conditions are ordinary flexible conditions which can be easily established in places outside of laboratories. Therefore, cell packaging and storage using the hydrogel incorporated within the microchip would be a promising miniature and portable solution for flexible supply and delivery of small amounts of cells from bench to bedside.

  3. Chitosan hydrogels enriched with polyphenols: Antibacterial activity, cell adhesion and growth and mineralization.

    Science.gov (United States)

    Lišková, Jana; Douglas, Timothy E L; Beranová, Jana; Skwarczyńska, Agata; Božič, Mojca; Samal, Sangram Keshari; Modrzejewska, Zofia; Gorgieva, Selestina; Kokol, Vanja; Bačáková, Lucie

    2015-09-20

    Injectable hydrogels for bone regeneration consisting of chitosan, sodium beta-glycerophosphate (Na-β-GP) and alkaline phosphatase (ALP) were enriched with the polyphenols phloroglucinol (PG) and gallic acid (GA) and characterized physicochemically and biologically with respect to properties relevant for applications in bone regeneration, namely gelation kinetics, mineralizability, antioxidant properties, antibacterial activity, cytocompatibility and ability to support adhesion and growth of human osteoblast-like MG63 cells. Enrichment with PG and GA had no negative effect on gelation kinetics and mineralizability. PG and GA both enhanced antioxidant activity of unmineralized hydrogels. Mineralization reduced antioxidant activity of hydrogels containing GA. Hydrogels containing GA, PG and without polyphenols reduced colony forming ability of Escherichia coli after 1h, 3h and 6h incubation and slowed E. coli growth in liquid culture for 150min. Hydrogels containing GA were cytotoxic and supported cell growth more poorly than polyphenol-free hydrogels. PG had no negative effect on cell adhesion and growth.

  4. Multifunctional fluorescent magnetic nanoparticles for lung cancer stem cells research.

    Science.gov (United States)

    Zhou, Xuan; Chen, Lisha; Wang, Anxin; Ma, Yufei; Zhang, Hailu; Zhu, Yimin

    2015-10-01

    In this paper, a multifunctional peptide-fluorescent-magnetic nanocomposites (Fe₃O₄@PEI@Cy5.5@PEG@HCBP-1 NPs) was synthesized via a layer-by-layer approach for potential application to cancer diagnoses. The multifunctional nanocomposites have great dispersibility and homogeneous particle sizes in aqueous solution. Meanwhile, it has perfect hemocompatibility and satisfying cytocompatibility in a relatively high concentration. Data from in vitro cytotoxicity assay indicated that the nanocomposites could recognize the lung cancer stem cells (CSCs) specifically and enrich the HCBP-1 positive CSCs from H460 tumor xenografts effectively. Additionally, the results of in vivo live fluorescent imaging and magnetic resonance imaging (MRI) showed that the nanocomposites could identify lung CSCs in tumor xenografts. These results suggested that the nanocomposites could be used as a potential cancer diagnostic agent through modifying diverse fluorescence dyes and targeting ligands on its surface.

  5. Assessment of using laponite cross-linked poly(ethylene oxide) for controlled cell adhesion and mineralization.

    Science.gov (United States)

    Gaharwar, Akhilesh K; Schexnailder, Patrick J; Kline, Benjamin P; Schmidt, Gudrun

    2011-02-01

    The in vitro cytocompatibility of silicate (Laponite clay) cross-linked poly(ethylene oxide) (PEO) nanocomposite films using MC3T3-E1 mouse preosteoblast cells was investigated while cell adhesion, spreading, proliferation and mineralization were assessed as a function of film composition. By combining the advantageous characteristics of PEO polymer (hydrophilic, prevents protein and cell adhesion) with those of a synthetic and layered silicate (charged, degradable and potentially bioactive) some of the physical and chemical properties of the resulting polymer nanocomposites could be controlled. Hydration, dissolution and mechanical properties were examined and related to cell adhesion. Overall, this feasibility study demonstrates the ability of using model Laponite cross-linked PEO nanocomposites to create bioactive scaffolds.

  6. Dual-functionalized graphene oxide for enhanced siRNA delivery to breast cancer cells.

    Science.gov (United States)

    Imani, Rana; Shao, Wei; Taherkhani, Samira; Emami, Shahriar Hojjati; Prakash, Satya; Faghihi, Shahab

    2016-11-01

    The aim of this study is to improve hydrocolloid stability and siRNA transfection ability of a reduced graphene oxide (rGO) based nano-carrier using a phospholipid-based amphiphilic polymer (PL-PEG) and cell penetrating peptide (CPPs). The dual functionalized nano-carrier is comprehensively characterized for its chemical structure, size, surface charge and morphology as well as thermal stability. The nano-carrier cytocompatibility, siRNA condensation ability both in the presence and absence of enzyme, endosomal buffering capacity, cellular uptake and intracellular localization are also assessed. The siRNA loaded nano-carrier is used for internalization to MCF-7 cells and its gene silencing ability is compared with AllStars Hs Cell Death siRNA as a model gene. The nano-carrier remains stable in biological solution, exhibits excellent cytocompatibility, retards the siRNA migration and protects it against enzyme degradation. The buffering capacity analysis shows that incorporation of the peptide in nano-carrier structure would increase the resistance to endo/lysosomal like acidic condition (pH 6-4) The functionalized nano-carrier which is loaded with siRNA in an optimal N:P ratio presents superior internalization efficiency (82±5.1% compared to HiPerFect(®)), endosomal escape quality and capable of inducing cell death in MCF-7 cancer cells (51±3.1% compared to non-treated cells). The success of siRNA-based therapy is largely dependent on the safe and efficient delivery system, therefore; the dual functionalized rGO introduced here could have a great potential to be used as a carrier for siRNA delivery with relevancy in therapeutics and clinical applications.

  7. Magnetic-directed patterning of cell spheroids.

    Science.gov (United States)

    Whatley, Benjamin R; Li, Xiaowei; Zhang, Ning; Wen, Xuejun

    2014-05-01

    We have described an approach to fabricate three-dimensional (3D) cell-based structures using functionalized super paramagnetic iron oxide nanoparticles (SPIONs) as patterning agents to guide the assembly of endothelial cell spheroids into 3D patterns using the magnetic forces generated by a prefabricated magnetic template. SPIONs were first uptaken by endothelial cells before they were assembled into uniform-sized spheroids through a home-made robotic spheroid maker. To guide the magnetic spheroids, a unique magnetic template was fabricated using computer-aided design and cut from a magnetic sheet. The spheroids were then guided to the prefabricated magnetic template through the attractive magnetic forces between the SPIONs inside the endothelial cells and the magnetic template. Fusion of endothelial cell spheroids over time while adhered to the magnetic template allowed for the formation of 3D cell-based structures. Subsequent removal of the prefabricated magnetic template left 3-D endothelial cell sheets, which may be stacked to fabricate complicated 3D multicellular tissue structures. To enhance the cytocompatibility, SPIONs were silica-coated before use. At low concentrations, the SPIONs did not adversely affect cell viability, proliferation, and phenotype stability. Light and confocal microscopy showed that endothelial cell spheroids could be reproducibly created with high uniformity. The endothelial cells were able to remain viable and maintain the 3D structure in vitro. We have proved the concept to use SPIONs as a patterning agent to direct the attachment and self assembly of SPION-loaded endothelial cell spheroids on a prefabricated magnetic template for the formation of 3D cell based structures. A magnetic-directed technique allows quick patterning of cell spheroids in accordance with desirable magnetic patterns, therefore, holding promise for scalable fabrication of complicated 3D multicellular tissue structures. By varying the cell types and the

  8. Biophysical response of living cells to boron nitride nanoparticles: uptake mechanism and bio-mechanical characterization

    Energy Technology Data Exchange (ETDEWEB)

    Rasel, Md. Alim Iftekhar; Li, Tong; Nguyen, Trung Dung; Singh, Sanjleena [Queensland University of Technology (QUT), School of Chemistry, Physics and Mechanical Engineering (Australia); Zhou, Yinghong; Xiao, Yin [Queensland University of Technology (QUT), Institute of Health and Biomedical Innovation (Australia); Gu, YuanTong, E-mail: yuantong.gu@qut.edu.au [Queensland University of Technology (QUT), School of Chemistry, Physics and Mechanical Engineering (Australia)

    2015-11-15

    Boron nitride nanomaterials have attracted significant interest due to their superior chemical and physical properties. Despite these novel properties, investigation on the interaction between boron nitride nanoparticle (BN NP) and living systems has been limited. In this study, BN NP (100–250 nm) is assessed as a promising biomaterial for medical applications. The toxicity of BN NP is evaluated by assessing the cells behaviours both biologically (MTT assay, ROS detection etc.) and physically (atomic force microscopy). The uptake mechanism of BN NP is studied by analysing the alternations in cellular morphology based on cell imaging techniques. The results demonstrate in vitro cytocompatibility of BN NP with immense potential for use as an effective nanoparticle for various bio-medical applications.

  9. Biophysical response of living cells to boron nitride nanoparticles: uptake mechanism and bio-mechanical characterization

    Science.gov (United States)

    Rasel, Md. Alim Iftekhar; Li, Tong; Nguyen, Trung Dung; Singh, Sanjleena; Zhou, Yinghong; Xiao, Yin; Gu, YuanTong

    2015-11-01

    Boron nitride nanomaterials have attracted significant interest due to their superior chemical and physical properties. Despite these novel properties, investigation on the interaction between boron nitride nanoparticle (BN NP) and living systems has been limited. In this study, BN NP (100-250 nm) is assessed as a promising biomaterial for medical applications. The toxicity of BN NP is evaluated by assessing the cells behaviours both biologically (MTT assay, ROS detection etc.) and physically (atomic force microscopy). The uptake mechanism of BN NP is studied by analysing the alternations in cellular morphology based on cell imaging techniques. The results demonstrate in vitro cytocompatibility of BN NP with immense potential for use as an effective nanoparticle for various bio-medical applications.

  10. Porous titanium-niobium alloys with different porosities:biomechanical strength and cytocompatibility%不同孔隙率多孔钛铌合金的生物力学强度及细胞生物相容性

    Institute of Scientific and Technical Information of China (English)

    王雷; 李强

    2016-01-01

    背景:钛铌合金具有较高的生物力学强度及较低的弹性模量,更加接近于人皮质骨,目前已被广泛作为牙科、骨科及人工髋关节植入材料。  目的:观察不同孔隙率多孔钛铌合金的生物力学强度及细胞相容性。  方法:利用粉末冶金技术制备40%、70%孔隙率的多孔钛铌合金,检测两种多孔钛铌合金的孔径、弹性模量及抗压强度。将兔骨髓间充质干细胞分别接种于40%、70%孔隙率的多孔钛铌合金表面,接种3,24,72 h,观察细胞黏附与增殖情况。  结果与结论:①多孔钛铌合金孔径为200-500μm,两种均以350,400μm孔径为主,孔隙间三维连通,材料表面粗糙,70%孔隙率组孔隙呈蜂窝状,部分断裂,孔隙间连通;40%孔隙率组孔隙分布不均匀,孔隙间少有连通;两组钛铌合金均具有较高的抗压强度及较低的弹性模量,组间比较无差异;②两组钛铌合金均有利于细胞的黏附,70%孔隙率组表面的细胞黏附数量多于40%孔隙率组(P<0.05),且70%孔隙率组表面可见细胞外基质已形成,结果表明70%孔隙率多孔钛铌合金更有利于细胞的黏附。%BACKGROUND:Titanium-niobium al oy holds high biomechanical strength and low elastic modulus that is close to the human cortical bone, so it has been extensively used as implant materials of dental, orthopedics and artificial hip joints. OBJECTIVE:To observe the biomechanical strength and cytocompatibility of porous titanium-niobium al oys with different porosities. METHODS:Porous titanium-niobium al oys with the porosity of 40%and 70%were prepared using powder metal urgy technology. Afterwards, the pore size, elasticity modulus and compressive strength of the two al oys were detected. Then the rabbit bone marrow mesenchymal stem cel s were seeded onto the 40%and 70%porous titanium-niobium al oys, and cel adhesion and proliferation were observed at 3, 24 and 72

  11. Cells

    Directory of Open Access Journals (Sweden)

    Zhao-Hui Jin

    2012-11-01

    Full Text Available As cancer stem cells (CSCs are postulated to play critical roles in cancer development, including metastasis and recurrence, CSC imaging would provide valuable information for cancer treatment and lead to CSC-targeted therapy. To assess the possibility of in vivo CSC targeting, we conducted basic studies on radioimmunotargeting of cancer cells positive for CD133, a CSC marker recognized in various cancers. Antibodies against CD133 were labeled with 125I, and their in vitro cell binding properties were tested. Using the same isotype IgG as a control, in vivo biodistribution of the labeled antibody retaining immunoreactivity was examined in mice bearing an HCT116 xenograft in which a population of the cancer cells expressed CD133. Intratumoral distribution of the labeled antibody was examined and compared to the CD133 expression pattern. The 125I-labeled anti-CD133 antibody showed a modest but significantly higher accumulation in the HCT116 xenograft compared to the control IgG. The intratumoral distribution of the labeled antibody mostly overlapped with the CD133 expression, whereas the control IgG was found in the area close to the necrotic tumor center. Our results indicate that noninvasive in vivo targeting of CSCs could be possible with radiolabeled antibodies against cell membrane markers.

  12. Chitosan-gelatin scaffolds for tissue engineering: physico-chemical properties and biological response of buffalo embryonic stem cells and transfectant of GFP-buffalo embryonic stem cells.

    Science.gov (United States)

    Thein-Han, W W; Saikhun, J; Pholpramoo, C; Misra, R D K; Kitiyanant, Y

    2009-11-01

    The favorable cellular response of newly developed cell line, buffalo embryonic stem (ES) cells to three-dimensional biodegradable chitosan-gelatin composite scaffolds with regard to stem-cell-based tissue engineering is described. Chitosan-gelatin composites were characterized by a highly porous structure with interconnected pores, and the mechanical properties were significantly enhanced. Furthermore, X-ray diffraction study indicated increased amorphous content in the scaffold on the addition of gelatin to chitosan. To develop a transfectant of green fluorescence protein (GFP)-buffalo ES cell, transfection of GFP plasmid to the cell was carried out via the electroporation procedure. In comparison with pure chitosan, cell spreading and proliferation were greater in highly visualized GFP-expressing cell-chitosan-gelatin scaffold constructs. The relative comparison of biological response involving cell proliferation and viability on the scaffolds suggests that blending of gelatin in chitosan improved cellular efficiency. Studies involving scanning electron and fluorescence microscopy, histological observations and flow cytometer analysis of the constructs implied that the polygonal cells attached to and penetrated the pores, and proliferated well, while maintaining their pluripotency during the culture period for 28days. Chitosan-gelatin scaffolds were cytocompatible with respect to buffalo ES cells. The study underscores for the first time that chitosan-gelatin scaffolds are promising candidates for ES-cell-based tissue engineering.

  13. Phenotypic nutrient up-take differences in an alley cropping system in semi-arid Machakos, Kenya

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Alley cropping of Cassia siamea and maize was studied insemi-arid Kenya for soil fertility improvement. Katumani composite maize was planted except in the short rains of 1988 (SR88) when a hybrid variety was sown. Therefore the grain yield per row increased differently in the alley cropped maize (CM). Sole maize (SM) and CM yields were higher in SR88 than in the long rains of 1988 (LR88) by 62% and 38%, while yields from the same treatments in LR89 were only 21% and 45% of those in SR88. These differences in relative maize yields are attributed to differences between the two maize varieties in competition under nutrient stress conditions.

  14. Effect of Arbuscular Mycorrhiza Fungi Inoculation on Growth and Up take of Mineral Nutrition in Ipomoea Aquatica.

    Directory of Open Access Journals (Sweden)

    Milton Halder

    2015-04-01

    Full Text Available A green house experiment was conducted to investigate the effect of arbuscular mycorrhiza inoculation on plant growth and uptake of mineral nutrition in Ipomoea aquatica considering the objective of using environmental friendly biofertilizer instead of chemical fertilizer. A common leafy vegetable plant Ipomoea aquatica was grown with mycorrhiza and without mycorrhiza for 42 days. After harvest the plants were analyzed for mineral nutrition concentration. Plant fresh weight, dry weight, macronutrient (P, K, Mg, Na, micronutrient (Fe, Mn, Zn concentration was higher in arbuscular mycorrhiza inoculated plant than non-mycorrhiza inoculated plant. For sustainable agriculture, introducing biofertilizer by using arbuscular mycorrhiza inoculation would be one of the most efficient techniques for replacing chemical fertilizer to meet the nutrient deficiency in nutrient deficient soils of Bangladesh.

  15. Interaction between mesenchymal stem cells and Ti-30Ta alloy after surface treatment.

    Science.gov (United States)

    Capellato, Patricia; Escada, Ana L A; Popat, Ketul C; Claro, Ana P R Alves

    2014-07-01

    In this study, in vitro cytocompatibility was investigated in the Ti-30Ta alloy after two kinds of surfaces treatments: alkaline and biomimetic treatment. Each condition was evaluated by scanning electron microscopy/energy-dispersive X-ray spectroscopy. Cellular adhesion, viability, protein expression, morphology, and differentiation were evaluated with Bone marrow stromal cells (MSCs) to investigate the short and long-term cellular response by fluorescence microscope imaging and colorimetric assays techniques. Two treatments exhibited similar results with respect to total protein content and enzyme activity as compared with alloy without treatment. However, it was observed improved of the biomineralization, bone matrix formation, enzyme activity, and MSCs functionality after biomimetic treatment. These results indicate that the biomimetic surface treatment has a high potential for enhanced osseointegration.

  16. Fabrication of uniform multi-compartment particles using microfludic electrospray technology for cell co-culture studies.

    Science.gov (United States)

    Liu, Zhou; Shum, Ho Cheung

    2013-01-01

    In this work, we demonstrate a robust and reliable approach to fabricate multi-compartment particles for cell co-culture studies. By taking advantage of the laminar flow within our microfluidic nozzle, multiple parallel streams of liquids flow towards the nozzle without significant mixing. Afterwards, the multiple parallel streams merge into a single stream, which is sprayed into air, forming monodisperse droplets under an electric field with a high field strength. The resultant multi-compartment droplets are subsequently cross-linked in a calcium chloride solution to form calcium alginate micro-particles with multiple compartments. Each compartment of the particles can be used for encapsulating different types of cells or biological cell factors. These hydrogel particles with cross-linked alginate chains show similarity in the physical and mechanical environment as the extracellular matrix of biological cells. Thus, the multi-compartment particles provide a promising platform for cell studies and co-culture of different cells. In our study, cells are encapsulated in the multi-compartment particles and the viability of cells is quantified using a fluorescence microscope after the cells are stained for a live/dead assay. The high cell viability after encapsulation indicates the cytocompatibility and feasibility of our technique. Our multi-compartment particles have great potential as a platform for studying cell-cell interactions as well as interactions of cells with extracellular factors.

  17. Cellular internalization of LiNbO3 nanocrystals for second harmonic imaging and the effects on stem cell differentiation

    Science.gov (United States)

    Li, Jianhua; Qiu, Jichuan; Guo, Weibo; Wang, Shu; Ma, Baojin; Mou, Xiaoning; Tanes, Michael; Jiang, Huaidong; Liu, Hong

    2016-03-01

    Second harmonic generation (SHG) nanocrystals have recently been reported to label cancer cells and other functional cell lines due to their unique double-frequency property. In this paper, we report for the first time the use of lithium niobate (LiNbO3, LN) nanocrystals as SHG labels for imaging stem cells. Rat mesenchymal stem cells (rMSCs) were labeled with LN nanocrystals in order to study the cellular internalization of the nanocrystals and the influence on stem cell differentiation. The results showed that LN nanocrystals were endocytosed by the rMSCs and the distribution of the internalized nanoparticles demonstrated a high consistency with the orientation of the actin filaments. Besides, LN-labeled rMSCs showed a concentration-dependent viability. Most importantly, rMSCs labeled with 50 μg per mL of LN nanocrystals retained their ability to differentiate into both osteogenic and adipogenic lineages. The results prove that LN nanocrystals can be used as a cytocompatible, near-infrared (NIR) light driven cell label for long-term imaging, without hindering stem cell differentiation. This work will promote the use of LN nanocrystals to broader applications like deep-tissue tracking, remote drug delivery and stem cell therapy.Second harmonic generation (SHG) nanocrystals have recently been reported to label cancer cells and other functional cell lines due to their unique double-frequency property. In this paper, we report for the first time the use of lithium niobate (LiNbO3, LN) nanocrystals as SHG labels for imaging stem cells. Rat mesenchymal stem cells (rMSCs) were labeled with LN nanocrystals in order to study the cellular internalization of the nanocrystals and the influence on stem cell differentiation. The results showed that LN nanocrystals were endocytosed by the rMSCs and the distribution of the internalized nanoparticles demonstrated a high consistency with the orientation of the actin filaments. Besides, LN-labeled rMSCs showed a concentration

  18. Protocol and cell responses in three-dimensional conductive collagen gel scaffolds with conductive polymer nanofibres for tissue regeneration.

    Science.gov (United States)

    Sirivisoot, Sirinrath; Pareta, Rajesh; Harrison, Benjamin S

    2014-02-06

    It has been established that nerves and skeletal muscles respond and communicate via electrical signals. In regenerative medicine, there is current emphasis on using conductive nanomaterials to enhance electrical conduction through tissue-engineered scaffolds to increase cell differentiation and tissue regeneration. We investigated the role of chemically synthesized polyaniline (PANI) and poly(3,4-ethylenedioxythiophene) (PEDOT) conductive polymer nanofibres for conductive gels. To mimic a naturally derived extracellular matrix for cell growth, type I collagen gels were reconstituted with conductive polymer nanofibres and cells. Cell viability and proliferation of PC-12 cells and human skeletal muscle cells on these three-dimensional conductive collagen gels were evaluated in vitro. PANI and PEDOT nanofibres were found to be cytocompatible with both cell types and the best results (i.e. cell growth and gel electrical conductivity) were obtained with a low concentration (0.5 wt%) of PANI. After 7 days of culture in the conductive gels, the densities of both cell types were similar and comparable to collagen positive controls. Moreover, PC-12 cells were found to differentiate in the conductive hydrogels without the addition of nerve growth factor or electrical stimulation better than collagen control. Importantly, electrical conductivity of the three-dimensional gel scaffolds increased by more than 400% compared with control. The increased conductivity and injectability of the cell-laden collagen gels to injury sites in order to create an electrically conductive extracellular matrix makes these biomaterials very conducive for the regeneration of tissues.

  19. Adhesion, vitality and osteogenic differentiation capacity of adipose derived stem cells seeded on nitinol nanoparticle coatings.

    Directory of Open Access Journals (Sweden)

    Sarah Strauss

    Full Text Available Autologous cells can be used for a bioactivation of osteoimplants to enhance osseointegration. In this regard, adipose derived stem cells (ASCs offer interesting perspectives in implantology because they are fast and easy to isolate. However, not all materials licensed for bone implants are equally suited for cell adhesion. Surface modifications are under investigation to promote cytocompatibility and cell growth. The presented study focused on influences of a Nitinol-nanoparticle coating on ASCs. Possible toxic effects as well as influences on the osteogenic differentiation potential of ASCs were evaluated by viability assays, scanning electron microscopy, immunofluorescence and alizarin red staining. It was previously shown that Nitinol-nanoparticles exert no cell toxic effects to ASCs either in soluble form or as surface coating. Here we could demonstrate that a Nitinol-nanoparticle surface coating enhances cell adherence and growth on Nitinol-surfaces. No negative influence on the osteogenic differentiation was observed. Nitinol-nanoparticle coatings offer new possibilities in implantology research regarding bioactivation by autologous ASCs, respectively enhancement of surface attraction to cells.

  20. Adhesion, vitality and osteogenic differentiation capacity of adipose derived stem cells seeded on nitinol nanoparticle coatings.

    Science.gov (United States)

    Strauss, Sarah; Neumeister, Anne; Barcikowski, Stephan; Kracht, Dietmar; Kuhbier, Jörn W; Radtke, Christine; Reimers, Kerstin; Vogt, Peter M

    2013-01-01

    Autologous cells can be used for a bioactivation of osteoimplants to enhance osseointegration. In this regard, adipose derived stem cells (ASCs) offer interesting perspectives in implantology because they are fast and easy to isolate. However, not all materials licensed for bone implants are equally suited for cell adhesion. Surface modifications are under investigation to promote cytocompatibility and cell growth. The presented study focused on influences of a Nitinol-nanoparticle coating on ASCs. Possible toxic effects as well as influences on the osteogenic differentiation potential of ASCs were evaluated by viability assays, scanning electron microscopy, immunofluorescence and alizarin red staining. It was previously shown that Nitinol-nanoparticles exert no cell toxic effects to ASCs either in soluble form or as surface coating. Here we could demonstrate that a Nitinol-nanoparticle surface coating enhances cell adherence and growth on Nitinol-surfaces. No negative influence on the osteogenic differentiation was observed. Nitinol-nanoparticle coatings offer new possibilities in implantology research regarding bioactivation by autologous ASCs, respectively enhancement of surface attraction to cells.

  1. Injectable in situ forming xylitol-PEG-based hydrogels for cell encapsulation and delivery.

    Science.gov (United States)

    Selvam, Shivaram; Pithapuram, Madhav V; Victor, Sunita P; Muthu, Jayabalan

    2015-02-01

    Injectable in situ crosslinking hydrogels offer unique advantages over conventional prefabricated hydrogel methodologies. Herein, we synthesize poly(xylitol-co-maleate-co-PEG) (pXMP) macromers and evaluate their performance as injectable cell carriers for tissue engineering applications. The designed pXMP elastomers were non-toxic and water-soluble with viscosity values permissible for subcutaneous injectable systems. pXMP-based hydrogels prepared via free radical polymerization with acrylic acid as crosslinker possessed high crosslink density and exhibited a broad range of compressive moduli that could match the natural mechanical environment of various native tissues. The hydrogels displayed controlled degradability and exhibited gradual increase in matrix porosity upon degradation. The hydrophobic hydrogel surfaces preferentially adsorbed albumin and promoted cell adhesion and growth in vitro. Actin staining on cells cultured on thin hydrogel films revealed subconfluent cell monolayers composed of strong, adherent cells. Furthermore, fabricated 3D pXMP cell-hydrogel constructs promoted cell survival and proliferation in vitro. Cumulatively, our results demonstrate that injectable xylitol-PEG-based hydrogels possess excellent physical characteristics and exhibit exceptional cytocompatibility in vitro. Consequently, they show great promise as injectable hydrogel systems for in situ tissue repair and regeneration.

  2. Cell-in-Shell Hybrids: Chemical Nanoencapsulation of Individual Cells.

    Science.gov (United States)

    Park, Ji Hun; Hong, Daewha; Lee, Juno; Choi, Insung S

    2016-05-17

    Nature has developed a fascinating strategy of cryptobiosis ("secret life") for counteracting the stressful, and often lethal, environmental conditions that fluctuate sporadically over time. For example, certain bacteria sporulate to transform from a metabolically active, vegetative state to an ametabolic endospore state. The bacterial endospores, encased within tough biomolecular shells, withstand the extremes of harmful stressors, such as radiation, desiccation, and malnutrition, for extended periods of time and return to a vegetative state by breaking their protective shells apart when their environment becomes hospitable for living. Certain ciliates and even higher organisms, for example, tardigrades, and others are also found to adopt a cryptobiotic strategy for survival. A common feature of cryptobiosis is the structural presence of tough sheaths on cellular structures. However, most cells and cellular assemblies are not "spore-forming" and are vulnerable to the outside threats. In particular, mammalian cells, enclosed with labile lipid bilayers, are highly susceptible to in vitro conditions in the laboratory and daily life settings, making manipulation and preservation difficult outside of specialized conditions. The instability of living cells has been a main bottleneck to the advanced development of cell-based applications, such as cell therapy and cell-based sensors. A judicious question arises: can cellular tolerance against harmful stresses be enhanced by simply forming cell-in-shell hybrid structures? Experimental results suggest that the answer is yes. A micrometer-sized "Iron Man" can be generated by chemically forming an ultrathin (cell. Since the report on silica nanoencapsulation of yeast cells, in which cytoprotective yeast-in-silica hybrids were formed, several synthetic strategies have been developed to encapsulate individual cells in a cytocompatible fashion, mimicking the cryptobiotic cell-in-shell structures found in nature, for example

  3. Adhesion, Proliferation and Migration of NIH/3T3 Cells on Modified Polyaniline Surfaces

    Science.gov (United States)

    Rejmontová, Petra; Capáková, Zdenka; Mikušová, Nikola; Maráková, Nela; Kašpárková, Věra; Lehocký, Marián; Humpolíček, Petr

    2016-01-01

    Polyaniline shows great potential and promises wide application in the biomedical field thanks to its intrinsic conductivity and material properties, which closely resemble natural tissues. Surface properties are crucial, as these predetermine any interaction with biological fluids, proteins and cells. An advantage of polyaniline is the simple modification of its surface, e.g., by using various dopant acids. An investigation was made into the adhesion, proliferation and migration of mouse embryonic fibroblasts on pristine polyaniline films and films doped with sulfamic and phosphotungstic acids. In addition, polyaniline films supplemented with poly (2-acrylamido-2-methyl-1-propanesulfonic) acid at various ratios were tested. Results showed that the NIH/3T3 cell line was able to adhere, proliferate and migrate on the pristine polyaniline films as well as those films doped with sulfamic and phosphotungstic acids; thus, utilization of said forms in biomedicine appears promising. Nevertheless, incorporating poly (2-acrylamido-2-methyl-1-propanesulfonic) acid altered the surface properties of the polyaniline films and significantly affected cell behavior. In order to reveal the crucial factor influencing the surface/cell interaction, cell behavior is discussed in the context of the surface energy of individual samples. It was clearly demonstrated that the lesser the difference between the surface energy of the sample and cell, the more cyto-compatible the surface is. PMID:27649159

  4. Fabrication of poly (ϵ-caprolactone) microfiber scaffolds with varying topography and mechanical properties for stem cell-based tissue engineering applications.

    Science.gov (United States)

    Ko, Junghyuk; Mohtaram, Nima Khadem; Ahmed, Farid; Montgomery, Amy; Carlson, Michael; Lee, Patrick C D; Willerth, Stephanie M; Jun, Martin B G

    2014-01-01

    Highly porous poly (ϵ-caprolactone) microfiber scaffolds can be fabricated using electrospinning for tissue engineering applications. Melt electrospinning produces such scaffolds by direct deposition of a polymer melt instead of dissolving the polymer in a solvent as performed during solution electrospinning. The objective of this study was to investigate the significant parameters associated with the melt electrospinning process that influence fiber diameter and scaffold morphology, including processing temperature, collection distance, applied, voltage and nozzle size. The mechanical properties of these microfiber scaffolds varied with microfiber diameter. Additionally, the porosity of scaffolds was determined by combining experimental data with mathematical modeling. To test the cytocompatability of these fibrous scaffolds, we seeded neural progenitors derived from murine R1 embryonic stem cell lines onto these scaffolds, where they could survive, migrate, and differentiate into neurons; demonstrating the potential of these melt electrospun scaffolds for tissue engineering applications.

  5. Development of Composite Poly(Lactide-co-Glycolide)- Nanodiamond Scaffolds for Bone Cell Growth.

    Science.gov (United States)

    Brady, Mariea A; Renzing, Andrea; Douglas, Timothy E L; Liu, Qin; Wille, Sebastian; Parizek, Martin; Bacakova, Lucie; Kromka, Alexander; Jarosova, Marketa; Godier, Greetje; Warnkel, Patrick H

    2015-02-01

    There are relatively few nanotechnologies that can produce nanocomposite scaffolds for cell growth. Electrospinning has emerged as the foremost method of producing nanofibrous biomimetic scaffolds for tissue engineering applications. In this study diamond nanoparticles were integrated into a polymer solution to develop a nanocomposite scaffold containing poly(lactide-co-glycolide) (PLGA) loaded with diamond nanoparticles. To investigate the effect of adding diamond nanoparticles to PLGA scaffolds, primary human mesenchymal stem cells (hMSCs) were seeded on the scaffolds. The cytocompatibility results showed that addition of diamond nanoparticles did not impinge upon cell proliferation, nor was there a cytotoxic cellular response after 9 days in culture. Scanning electron microscopy, transmission electron microscopy, atomic force microscopy and confocal microscopy enabled qualitative characterization of the fibres and revealed cell morphology and number. Furthermore, surface roughness was measured to evaluate diamond nanoparticle modifications, and no significant difference was found between the diamond nanocomposite and pure polymer scaffolds. On the other hand, bright spots on phase images performed by atomic force microscopy suggested a higher hardness at certain points on fibers of the PLGA-nanodiamond composites, which was supported by nanoindentation measurements. This study shows that PLGA nanofibers can be reinforced with nanodiamond without adversely affecting cell behaviour, and thus it sets the foundation for future application of these scaffolds in bone tissue engineering.

  6. Fabrication of endothelial progenitor cell capture surface via DNA aptamer modifying dopamine/polyethyleneimine copolymer film

    Science.gov (United States)

    Li, Xin; Deng, Jinchuan; Yuan, Shuheng; Wang, Juan; Luo, Rifang; Chen, Si; Wang, Jin; Huang, Nan

    2016-11-01

    Endothelial progenitor cells (EPCs) are mainly located in bone marrow and circulate, and play a crucial role in repairmen of injury endothelium. One of the most promising strategies of stents designs were considered to make in-situ endothelialization in vivo via EPC-capture biomolecules on a vascular graft to capture EPCs directly from circulatory blood. In this work, an EPC specific aptamer with a 34 bases single strand DNA sequence was conjugated onto the stent surface via dopamine/polyethyleneimine copolymer film as a platform and linker. The assembled density of DNA aptamer could be regulated by controlling dopamine percentage in this copolymer film. X-ray photoelectron spectroscopy (XPS), water contact angle (WCA) and fluorescence test confirmed the successful immobilization of DNA aptamer. To confirm its biofunctionality and cytocompatibility, the capturing cells ability of the aptamer modified surface and the effects on the growth behavior of human umbilical vein endothelial cells (HUVECs), smooth muscle cells (SMCs) were investigated. The aptamer functionalized sample revealed a good EPC-capture ability, and had a cellular friendly feature for both EPC and EC growth, while not stimulated the hyperplasia of SMCs. And, the co-culture experiment of three types of cells confirmed the specificity capturing of EPCs to aptamer modified surface, rather than ECs and SMCs. These data suggested that this aptamer functionalized surface may have a large potentiality for the application of vascular grafts with targeted endothelialization.

  7. Endothelial cell functions in vitro cultured on poly(L-lactic acid) membranes modified with different methods.

    Science.gov (United States)

    Zhu, Yabin; Gao, Changyou; Liu, Yunxiao; Shen, Jiacong

    2004-06-01

    We recently developed several methods to enhance the cell-polymer interactions. Optimal conditions for each method have been revealed separately by in vitro cell culture. As a practical consideration for construction of tissue-engineered organs, it is necessary to consider which is the most suitable and convenient in clinical applications. To compare the efficiency of these methods with respect to cell functions, poly-L-lactic acid (PLLA) was selected as matrix being modified by 1) aminolysis (PLLA-NH(2)), 2) collagen immobilization with GA (PLLA-GA-Col), 3) chondroitin sulfate (CS)/collagen layer-by-layer (LBL) assembly (PLLA-CS/Col), 4) photo-induced grafting copolymerization of hydrophilic methacrylic acid (MAA) (PLLA-g-PMAA), and 5) further immobilization of collagen with 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride (EDAC) (PLLA-g-PMAA-Col). The surface wettability of the modified PLLA was determined by water contact angle measurements. The cell response to the modified PLLA was quantitatively assessed and compared by using human umbilical endothelial cells (HUVECs) culture. Our results indicate that all the modifications can improve the cytocompatibility of PLLA (e.g., cells can attach with spreading morphology, proliferate and secret vWF and 6-keto-PGF(1 alpha)). All the collagen-modified PLLA showed more positive cell response than those purely aminolyzed or PMAA grafted. Among all the methods, collagen immobilization by LBL assembly or GA bridging after aminolysis is more acceptable for the convenience and applicability to scaffolds.

  8. Biodegradable electrospun nanofibers coated with platelet-rich plasma for cell adhesion and proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Diaz-Gomez, Luis [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Alvarez-Lorenzo, Carmen, E-mail: carmen.alvarez.lorenzo@usc.es [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Concheiro, Angel [Departamento de Farmacia y Tecnología Farmacéutica, Facultad de Farmacia, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Silva, Maite [Instituto de Ortopedia y Banco de Tejidos Musculoesqueléticos, Universidad de Santiago de Compostela, 15872 Santiago de Compostela (Spain); Dominguez, Fernando [Fundación Publica Galega de Medicina Xenómica, Santiago de Compostela (Spain); Sheikh, Faheem A.; Cantu, Travis; Desai, Raj; Garcia, Vanessa L. [Department of Chemistry, University of Texas Pan American, Edinburg, TX 78541 (United States); Macossay, Javier, E-mail: jmacossay@utpa.edu [Department of Chemistry, University of Texas Pan American, Edinburg, TX 78541 (United States)

    2014-07-01

    Biodegradable electrospun poly(ε-caprolactone) (PCL) scaffolds were coated with platelet-rich plasma (PRP) to improve cell adhesion and proliferation. PRP was obtained from human buffy coat, and tested on human adipose-derived mesenchymal stem cells (MSCs) to confirm cell proliferation and cytocompatibility. Then, PRP was adsorbed on the PCL scaffolds via lyophilization, which resulted in a uniform sponge-like coating of 2.85 (S.D. 0.14) mg/mg. The scaffolds were evaluated regarding mechanical properties (Young's modulus, tensile stress and tensile strain), sustained release of total protein and growth factors (PDGF-BB, TGF-β1 and VEGF), and hemocompatibility. MSC seeded on the PRP–PCL nanofibers showed an increased adhesion and proliferation compared to pristine PCL fibers. Moreover, the adsorbed PRP enabled angiogenesis features observed as neovascularization in a chicken chorioallantoic membrane (CAM) model. Overall, these results suggest that PRP–PCL scaffolds hold promise for tissue regeneration applications. - Highlights: • Platelet-rich plasma (PRP) can be adsorbed on electrospun fibers via lyophilization. • PRP coating enhanced mesenchymal stem cell adhesion and proliferation on scaffolds. • PRP-coated scaffolds showed sustained release of growth factors. • Adsorbed PRP provided angiogenic features. • PRP-poly(ε-caprolactone) scaffolds hold promise for tissue regeneration applications.

  9. Influence of the addition of β-TCP on the morphology, thermal properties and cell viability of poly (lactic acid) fibers obtained by electrospinning

    Energy Technology Data Exchange (ETDEWEB)

    Siqueira, L. [Laboratory of Bioceramics, Institute of Science and Technology, UNIFESP, São José dos Campos, SP (Brazil); Passador, F.R. [Laboratory of Polymer Processing, Institute of Science and Technology, UNIFESP, São José dos Campos, SP (Brazil); Costa, M.M. [Laboratory of Biomedical Nanotechnology, Development Research Institute IP& D, UNIVAP, São José dos Campos, SP (Brazil); Lobo, A.O., E-mail: aolobo@pq.cnpq.br [Laboratory of Biomedical Nanotechnology, Development Research Institute IP& D, UNIVAP, São José dos Campos, SP (Brazil); Sousa, E., E-mail: eliandra.sousa@unifesp.br [Laboratory of Bioceramics, Institute of Science and Technology, UNIFESP, São José dos Campos, SP (Brazil)

    2015-07-01

    Electrospinning is a simple and low-cost way to fabricate fibers. Among the various polymers used in electrospinning process, the poly (lactic acid) (PLA) stands out due to its excellent biodegradability and biocompatibility. Calcium phosphate ceramics has been recognized as an attractive biomaterial because their chemical composition is similar to the mineral component of the hard tissue in the body. Furthermore, they are bioactive and osteoinductive and some are even quite biodegradable. The beta-tricalcium phosphate (β-TCP) particles were synthesized by solid state reaction. Different contents of β-TCP particles were incorporated in polymer matrices to form fibers of PLA/β-TCP composites by electrospinning aiming a possible application as a scaffold for tissue engineering. The fibers were characterized by scanning electron microscopy (SEM), infrared (FTIR), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The average diameter of the fibers varied in the range of 260–519.6 ± 50 nm. The presence of β-TCP particles promoted changes on thermal properties of the fibers. The composite with 8 wt-% of β-TCP showed a low degree of crystallinity and can be used for application in tissue engineering. The cell viability was analyzed by reduction of the methyl tetrazolium salt by the pyruvate dehydrogenase enzymatic complex present in the matrix of mitochondria (MTT test). All PLA fiber groups, with different contents of β-TCP, showed cytocompatibility ability with non-cytotoxicity effect and bioactive properties using SBF assay. - Highlights: • PLA fibers with β-TCP particles incorporated were obtained by electrospinning aiming an application in tissue engineering.. • The average diameter of the fibers varied in the range of 260–519.6 ± 50 nm. • The composite with 8 wt.% of β-TCP showed a low degree of crystallinity and can be used for application in tissue engineering. • All PLA fibers groups, with different contents of

  10. Osteogenic Capacity of Human Adipose-Derived Stem Cells is Preserved Following Triggering of Shape Memory Scaffolds.

    Science.gov (United States)

    Tseng, Ling-Fang; Wang, Jing; Baker, Richard M; Wang, Guirong; Mather, Patrick T; Henderson, James H

    2016-08-01

    Recent advances in shape memory polymers have enabled the study of programmable, shape-changing, cytocompatible tissue engineering scaffolds. For treatment of bone defects, scaffolds with shape memory functionality have been studied for their potential for minimally invasive delivery, conformal fitting to defect margins, and defect stabilization. However, the extent to which the osteogenic differentiation capacity of stem cells resident in shape memory scaffolds is preserved following programmed shape change has not yet been determined. As a result, the feasibility of shape memory polymer scaffolds being employed in stem cell-based treatment strategies remains unclear. To test the hypothesis that stem cell osteogenic differentiation can be preserved during and following triggering of programmed architectural changes in shape memory polymer scaffolds, human adipose-derived stem cells were seeded in shape memory polymer foam scaffolds or in shape memory polymer fibrous scaffolds programmed to expand or contract, respectively, when warmed to body temperature. Osteogenic differentiation in shape-changing and control scaffolds was compared using mineral deposition, protein production, and gene expression assays. For both shape-changing and control scaffolds, qualitatively and quantitatively comparable amounts of mineral deposition were observed; comparable levels of alkaline phosphatase activity were measured; and no significant differences in the expression of genetic markers of osteogenesis were detected. These findings support the feasibility of employing shape memory in scaffolds for stem cell-based therapies for bone repair.

  11. Influence of layer-by-layer assembled electrospun poly (L-lactic acid) nanofiber mats on the bioactivity of endothelial cells

    Science.gov (United States)

    Wu, Keke; Zhang, Xiazhi; Yang, Wufeng; Liu, Xiaoyan; Jiao, Yanpeng; Zhou, Changren

    2016-12-01

    Electrospun poly(L-lactic acid) (PLLA) nanofiber mats were successfully modified by deposition of multilayers with chitosan (CS), heparin (Hep) and graphene oxide (GO) through electrostatic layer-by-layer (LBL) self-assembly method. In this study, the surface properties of PLLA nanofiber mats before and after modification were investigated via scanning electron microscope (SEM), atomic force microscopy (AFM), attenuated total reflectance fourier transformation infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and water contact angle measurement. In addition, the cytocompatibility of the modified PLLA nanofiber mats were investigated by testing endothelial cells compatibility, including cell attachment, cell proliferation and cell cycle. The results revealed that the surfaces of modified PLLA nanofiber mats become much rougher, stifiness and the hydrophilicity of the LBL modified PLLA nanofiber mats were improved compared to original PLLA one. Moreover, the modified PLLA nanofiber mats had promoted the endothelial cells viability attachment significantly. Besides, we studied the PLLA nanofiber mats on the expression of necrosis factor (TNF-α), interleukine-1β (IL-1β), monocyte chemoattractant protein-1 (MCP-1) and vascular cell adhesion molecule-1 (VCAM-1) in endothelial cells. The results showed that modified PLLA nanofiber mats had inhibited the inflammatory response to some extent.

  12. One-pot synthesis of aptamer-functionalized silver nanoclusters for cell-type-specific imaging.

    Science.gov (United States)

    Li, Jingjing; Zhong, Xiaoqin; Cheng, Fangfang; Zhang, Jian-Rong; Jiang, Li-Ping; Zhu, Jun-Jie

    2012-05-01

    As an emerging category of fluorescent metal nanoclusters, oligonucleotide-templated silver nanoclusters (Ag NCs) have attracted a lot of interest and have shown wide application in biorelated disciplines. However, the weak fluorescence emission and poor permeability to cell membranes tethered further intracellular applications of Ag NCs. AS1411 is an antiproliferative G-rich phosphodiester oligonucleotide and currently an anticancer agent under phase II clinical trials. Herein, we present a strategy to synthesize AS1411-functionalized Ag NCs with excellent fluorescence through a facile one-pot process. Confocal laser scanning microscopy and Z-axis scanning confirmed that the AS1411-functionalized Ag NCs could be internalized into MCF-7 human breast cancer cells and were able to specifically stain nuclei with red color. To our surprise, 3-[4,5-dimethylthiazol-z-yl]-2,5-diphenyltetrazolium bromide (MTT) assay demonstrated the Ag NCs were cytocompatible and showed better inhibition effects than pure AS1411 on MCF-7 human breast cancer cells. In addition, a universal design of the oligonucleotide scaffold for synthesis of Ag NCs was extended to other aptamers, such as Sgc8c and mucin 1 aptamer. Due to the facile synthesis procedure and capability of specific target recognition, this fluorescent platform will potentially broaden the applications of Ag NCs in biosensing and biological imaging.

  13. Cytocompatible antifungal acrylic resin containing silver nanoparticles for dentures

    OpenAIRE

    Acosta-Torres LS; Mendieta I; Nuñez-Anita RE; Cajero-Juárez M; Castaño VM

    2012-01-01

    Laura Susana Acosta-Torres,1 Irasema Mendieta,2 Rosa Elvira Nuñez-Anita,3 Marcos Cajero-Juárez,3 Víctor M Castaño41National School of Higher Education, School of Dentistry - Leon Unit, National Autonomus University of Mexico (UNAM), Leon, Guanajuato, 2Neurobiology Institute, National Autonomus University of Mexico (UNAM), Juriquilla, Queretaro, 3Animal Biotechnology Laboratory, Faculty of Veterinary Medicine at San Nicolas de Hidalgo, Michoac&aa...

  14. Tubular Scaffold with Shape Recovery Effect for Cell Guide Applications

    Directory of Open Access Journals (Sweden)

    Kazi M. Zakir Hossain

    2015-07-01

    Full Text Available Tubular scaffolds with aligned polylactic acid (PLA fibres were fabricated for cell guide applications by immersing rolled PLA fibre mats into a polyvinyl acetate (PVAc solution to bind the mats. The PVAc solution was also mixed with up to 30 wt % β-tricalcium phosphate (β-TCP content. Cross-sectional images of the scaffold materials obtained via scanning electron microscopy (SEM revealed the aligned fibre morphology along with a significant number of voids in between the bundles of fibres. The addition of β-TCP into the scaffolds played an important role in increasing the void content from 17.1% to 25.3% for the 30 wt % β-TCP loading, which was measured via micro-CT (µCT analysis. Furthermore, µCT analyses revealed the distribution of aggregated β-TCP particles in between the various PLA fibre layers of the scaffold. The compressive modulus properties of the scaffolds increased from 66 MPa to 83 MPa and the compressive strength properties decreased from 67 MPa to 41 MPa for the 30 wt % β-TCP content scaffold. The scaffolds produced were observed to change into a soft and flexible form which demonstrated shape recovery properties after immersion in phosphate buffered saline (PBS media at 37 °C for 24 h. The cytocompatibility studies (using MG-63 human osteosarcoma cell line revealed preferential cell proliferation along the longitudinal direction of the fibres as compared to the control tissue culture plastic. The manufacturing process highlighted above reveals a simple process for inducing controlled cell alignment and varying porosity features within tubular scaffolds for potential tissue engineering applications.

  15. PEG-OCL micelles for quercetin solubilization and inhibition of cancer cell growth.

    Science.gov (United States)

    Khonkarn, Ruttiros; Mankhetkorn, Samlee; Hennink, Wim E; Okonogi, Siriporn

    2011-10-01

    In this study, quercetin (QCT), a flavonoid with high anticancer potential, was loaded into polymeric micelles of PEG-OCL (poly(ethylene glycol)-b-oligo(ε-caprolactone)) with naphthyl or benzyl end groups in order to increase its aqueous solubility. The cytostatic activity of the QCT-loaded micelles toward different human cancer cell lines and normal cells was investigated. The results showed that the solubility of QCT entrapped in mPEG750-b-OCL micelles was substantially increased up to 1 mg/ml, which is approximately 110 times higher than that of its solubility in water (9 μg/ml). The average particle size of QCT-loaded micelles ranged from 14 to 19 nm. The QCT loading capacity of the polymeric micelles with naphthyl groups was higher than that with benzyl groups (10% and 6%, respectively). QCT-loaded, benzyl- and naphthyl-modified micelles effectively inhibited the growth of both sensitive and resistance cancer cells (human erythromyelogenous leukemia cells (K562) and small lung carcinoma cells (GLC4)). However, the benzyl-modified micelles have a good cytocompatibility (in the concentration range investigated (up to 100 μg/ml), they are well tolerated by living cells), whereas their naphthyl counterparts showed some cytotoxicity at higher concentrations (60-100 μg/ml). Flow cytometry demonstrated that the mechanism underlying the growth inhibitory effect of QCT in its free form was inducing cell cycle arrest at the G2/M phase. Benzyl-modified micelles loaded with QCT also exhibited this cycle arresting the effect of cancer cells. In conclusion, this paper shows the enhancement of solubility and cell cycle arrest of QCT loaded into micelles composed of mPEG750-b-OCL modified with benzyl end groups. These micelles are therefore considered to be an attractive vehicle for the (targeted) delivery of QCT to tumors.

  16. Novel strontium-doped bioactive glass nanoparticles enhance proliferation and osteogenic differentiation of human bone marrow stromal cells

    Energy Technology Data Exchange (ETDEWEB)

    Strobel, L. A. [University of Erlangen-Nuremberg Medical Center, Department of Plastic and Hand Surgery (Germany); Hild, N.; Mohn, D.; Stark, W. J. [ETH Zurich, Department of Chemistry and Applied Biosciences, Institute for Chemical and Bioengineering (Switzerland); Hoppe, A. [University of Erlangen-Nuremberg, Department of Materials Science and Engineering, Institute of Biomaterials (Germany); Gbureck, U. [University of Wuerzburg, Department for Functional Materials in Medicine and Dentistry (Germany); Horch, R. E.; Kneser, U. [University of Erlangen-Nuremberg Medical Center, Department of Plastic and Hand Surgery (Germany); Boccaccini, A. R., E-mail: aldo.boccaccini@ww.uni-erlangen.de [University of Erlangen-Nuremberg, Department of Materials Science and Engineering, Institute of Biomaterials (Germany)

    2013-07-15

    The present study investigates a new family of bioactive glass nanoparticles with and without Sr-doping focusing on the influence of the nanoparticles on human bone marrow stromal cells (hBMSCs) in vitro. The bioactive glass nanoparticles were fabricated by flame spray synthesis and a particle diameter of 30-35 nm was achieved. Glass nanoparticles were undoped (BG 13-93-0Sr) or doped with 5 wt% strontium (Sr) (BG 13-93-5Sr) and used at concentrations of 10 and 100 {mu}g/cm Superscript-Two (particles per culture plate area), respectively. Cells were cultured for 14 days after which the samples were analysed regarding metabolic activity and expression of various bone-specific genes. Cell growth and morphology indicated the high cytocompatibility of the nanoparticulate bioactive glass. The presence of the nanoparticles enhanced cell growth compared to the plain polystyrene control group. At a concentration of 100 {mu}g/cm Superscript-Two , Sr-doped particles led to significantly enhanced gene expression of osteocalcin, collagen type 1 and vascular endothelial growth factor. Thus, Sr-doped nanoparticles showing a dose-dependent increase of osteogenic differentiation in hBMSCs are a promising biomaterial for bone regeneration purposes.

  17. Cyclodextrin-Modified Porous Silicon Nanoparticles for Efficient Sustained Drug Delivery and Proliferation Inhibition of Breast Cancer Cells.

    Science.gov (United States)

    Correia, Alexandra; Shahbazi, Mohammad-Ali; Mäkilä, Ermei; Almeida, Sérgio; Salonen, Jarno; Hirvonen, Jouni; Santos, Hélder A

    2015-10-21

    Over the past decade, the potential of polymeric structures has been investigated to overcome many limitations related to nanosized drug carriers by modulating their toxicity, cellular interactions, stability, and drug-release kinetics. In this study, we have developed a successful nanocomposite consisting of undecylenic acid modified thermally hydrocarbonized porous silicon nanoparticles (UnTHCPSi NPs) loaded with an anticancer drug, sorafenib, and surface-conjugated with heptakis(6-amino-6-deoxy)-β-cyclodextrin (HABCD) to show the impact of the surface polymeric functionalization on the physical and biological properties of the drug-loaded nanoparticles. Cytocompatibility studies showed that the UnTHCPSi-HABCD NPs were not toxic to breast cancer cells. HABCD also enhanced the suspensibility and both the colloidal and plasma stabilities of the UnTHCPSi NPs. UnTHCPSi-HABCD NPs showed a significantly increased interaction with breast cancer cells compared to bare NPs and also sustained the drug release. Furthermore, the sorafenib-loaded UnTHCPSi-HABCD NPs efficiently inhibited cell proliferation of the breast cancer cells.

  18. Enhanced adherence of mouse fibroblast and vascular cells to plasma modified polyethylene

    Energy Technology Data Exchange (ETDEWEB)

    Reznickova, Alena, E-mail: alena.reznickova@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Novotna, Zdenka, E-mail: zdenka1.novotna@vscht.cz [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Kolska, Zdenka [Faculty of Science, J.E. Purkyně University, 400 96 Usti nad Labem (Czech Republic); Kasalkova, Nikola Slepickova [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Rimpelova, Silvie [Department of Biochemistry and Microbiology, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic); Svorcik, Vaclav [Department of Solid State Engineering, Institute of Chemical Technology Prague, 166 28 Prague 6 (Czech Republic)

    2015-07-01

    Since the last decade, tissue engineering has shown a sensational promise in providing more viable alternatives to surgical procedures for harvested tissues, implants and prostheses. Biomedical polymers, such as low-density polyethylene (LDPE), high-density polyethylene (HDPE) and ultra-high molecular weight polyethylene (UHMWPE), were activated by Ar plasma discharge. Degradation of polymer chains was examined by determination of the thickness of ablated layer. The amount of an ablated polymer layer was measured by gravimetry. Contact angle, measured by goniometry, was studied as a function of plasma exposure and post-exposure aging times. Chemical structure of modified polymers was characterized by angle resolved X-ray photoelectron spectroscopy. Surface chemistry and polarity of the samples were investigated by electrokinetic analysis. Changes in surface morphology were followed using atomic force microscopy. Cytocompatibility of plasma activated polyethylene foils was studied using two distinct model cell lines; VSMCs (vascular smooth muscle cells) as a model for vascular graft testing and connective tissue cells L929 (mouse fibroblasts) approved for standardized material cytotoxicity testing. Specifically, the cell number, morphology, and metabolic activity of the adhered and proliferated cells on the polyethylene matrices were studied in vitro. It was found that the plasma treatment caused ablation of the polymers, resulting in dramatic changes in their surface morphology and roughness. ARXPS and electrokinetic measurements revealed oxidation of the polymer surface. It was found that plasma activation has a positive effect on the adhesion and proliferation of VSMCs and L929 cells. - Highlights: • Plasma activation of LDPE, HDPE and UHMWPE • Study of surface properties by several techniques: ARXPS, AFM, zeta-potential, and goniometry • Investigation of adhesion and spreading of vascular smooth muscle cells (VSMCs) and mouse fibroblasts (L929)

  19. Induction of osteogenic differentiation of adipose derived stem cells by microstructured nitinol actuator-mediated mechanical stress.

    Directory of Open Access Journals (Sweden)

    Sarah Strauß

    Full Text Available The development of large tissue engineered bone remains a challenge in vitro, therefore the use of hybrid-implants might offer a bridge between tissue engineering and dense metal or ceramic implants. Especially the combination of the pseudoelastic implant material Nitinol (NiTi with adipose derived stem cells (ASCs opens new opportunities, as ASCs are able to differentiate osteogenically and therefore enhance osseointegration of implants. Due to limited knowledge about the effects of NiTi-structures manufactured by selective laser melting (SLM on ASCs the study started with an evaluation of cytocompatibility followed by the investigation of the use of SLM-generated 3-dimensional NiTi-structures preseeded with ASCs as osteoimplant model. In this study we could demonstrate for the first time that osteogenic differentiation of ASCs can be induced by implant-mediated mechanical stimulation without support of osteogenic cell culture media. By use of an innovative implant design and synthesis via SLM-technique we achieved high rates of vital cells, proper osteogenic differentiation and mechanically loadable NiTi-scaffolds could be achieved.

  20. LBL coating of type I collagen and hyaluronic acid on aminolyzed PLLA to enhance the cell-material interaction

    Directory of Open Access Journals (Sweden)

    M. Y. Zhao

    2014-05-01

    Full Text Available The aim of the present work is to assemble extracellular matrix components onto poly (L-lactic acid (PLLA films using layer-by-layer (LBL depositing method to enhance the cell-material interaction. To introduce charges onto the hydrophobic and neutral PLLA surface so that the electronic assembly can be processed, poly (ethylene imine (PEI was covalently bonded to modify the PLLA films. Positively charged collagen I (Col I was then deposited onto the aminolyzed PLLA film surface in a LBL assembly manner using hyaluronic acid (HA as a negatively charged polyelectrolyte. The PEI modification efficiency was monitored via X-ray photoelectron spectroscopy (XPS measurements. The results of Surface Plasmon Resonance (SPR and Water contact angle (WCA monitoring the LBL assemble process presented that the HA/Col I deposited alternately onto the PLLA surface. The surface topography of the films was observed by Atomic force microscope (AFM. In vitro osteoblast culture found that the presence of Col I layer greatly improved the cytocompatibility of the PLLA films in terms of cell viability, cell proliferation and Alkaline Phosphatase (ALP expression. Furthermore, osteoblast extensions were found to be directed by contact guidance of the aligned Col I fibrils. Thus, these very flexible systems may allow broad applications for improve the bioactivity of polymeric materials, which might be a potential application for bone tissue engineering.

  1. Modeling Alveolar Epithelial Cell Behavior In Spatially Designed Hydrogel Microenvironments

    Science.gov (United States)

    Lewis, Katherine Jean Reeder

    The alveolar epithelium consists of two cell phenotypes, elongated alveolar type I cells (AT1) and rounded alveolar type II cells (ATII), and exists in a complex three-dimensional environment as a polarized cell layer attached to a thin basement membrane and enclosing a roughly spherical lumen. Closely surrounding the alveolar cysts are capillary endothelial cells as well as interstitial pulmonary fibroblasts. Many factors are thought to influence alveolar epithelial cell differentiation during lung development and wound repair, including physical and biochemical signals from the extracellular matrix (ECM), and paracrine signals from the surrounding mesenchyme. In particular, disrupted signaling between the alveolar epithelium and local fibroblasts has been implicated in the progression of several pulmonary diseases. However, given the complexity of alveolar tissue architecture and the multitude of signaling pathways involved, designing appropriate experimental platforms for this biological system has been difficult. In order to isolate key factors regulating cellular behavior, the researcher ideally should have control over biophysical properties of the ECM, as well as the ability to organize multiple cell types within the scaffold. This thesis aimed to develop a 3D synthetic hydrogel platform to control alveolar epithelial cyst formation, which could then be used to explore how extracellular cues influence cell behavior in a tissue-relevant cellular arrangement. To accomplish this, a poly(ethylene glycol) (PEG) hydrogel network containing enzymatically-degradable crosslinks and bioadhesive pendant peptides was employed as a base material for encapsulating primary alveolar epithelial cells. First, an array of microwells of various cross-sectional shapes was photopatterned into a PEG gel containing photo-labile crosslinks, and primary ATII cells were seeded into the wells to examine the role of geometric confinement on differentiation and multicellular arrangement

  2. Evaluation of biodegradable electric conductive tube-guides and mesenchymal stem cells

    Science.gov (United States)

    Ribeiro, Jorge; Pereira, Tiago; Caseiro, Ana Rita; Armada-da-Silva, Paulo; Pires, Isabel; Prada, Justina; Amorim, Irina; Amado, Sandra; França, Miguel; Gonçalves, Carolina; Lopes, Maria Ascensão; Santos, José Domingos; Silva, Dina Morais; Geuna, Stefano; Luís, Ana Lúcia; Maurício, Ana Colette

    2015-01-01

    AIM: To study the therapeutic effect of three tube-guides with electrical conductivity associated to mesenchymal stem cells (MSCs) on neuro-muscular regeneration after neurotmesis. METHODS: Rats with 10-mm gap nerve injury were tested using polyvinyl alcohol (PVA), PVA-carbon nanotubes (CNTs) and MSCs, and PVA-polypyrrole (PPy). The regenerated nerves and tibialis anterior muscles were processed for stereological studies after 20 wk. The functional recovery was assessed serially for gait biomechanical analysis, by extensor postural thrust, sciatic functional index and static sciatic functional index (SSI), and by withdrawal reflex latency (WRL). In vitro studies included cytocompatibility, flow cytometry, reverse transcriptase polymerase chain reaction and karyotype analysis of the MSCs. Histopathology of lung, liver, kidneys, and regional lymph nodes ensured the biomaterials biocompatibility. RESULTS: SSI remained negative throughout and independently from treatment. Differences between treted groups in the severity of changes in WRL existed, showing a faster regeneration for PVA-CNTs-MSCs (P < 0.05). At toe-off, less acute ankle joint angles were seen for PVA-CNTs-MSCs group (P = 0.051) suggesting improved ankle muscles function during the push off phase of the gait cycle. In PVA-PPy and PVA-CNTs groups, there was a 25% and 42% increase of average fiber area and a 13% and 21% increase of the “minimal Feret’s diameter” respectively. Stereological analysis disclosed a significantly (P < 0.05) increased myelin thickness (M), ratio myelin thickness/axon diameter (M/d) and ratio axon diameter/fiber diameter (d/D; g-ratio) in PVA-CNT-MSCs group (P < 0.05). CONCLUSION: Results revealed that treatment with MSCs and PVA-CNTs tube-guides induced better nerve fiber regeneration. Functional and kinematics analysis revealed positive synergistic effects brought by MSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy are promising scaffolds with electric conductive properties, bio

  3. Evaluation of biodegradable electric conductive tube-guidesand mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    2015-01-01

    AIM To study the therapeutic effect of three tubeguideswith electrical conductivity associated tomesenchymal stem cells (MSCs) on neuro-muscularregeneration after neurotmesis.METHODS: Rats with 10-mm gap nerve injury weretested using polyvinyl alcohol (PVA), PVA-carbonnanotubes (CNTs) and MSCs, and PVA-polypyrrole(PPy). The regenerated nerves and tibialis anteriormuscles were processed for stereological studies after20 wk. The functional recovery was assessed serially forgait biomechanical analysis, by extensor postural thrust,sciatic functional index and static sciatic functional index (SSI), and by withdrawal reflex latency (WRL). Invitro studies included cytocompatibility, flow cytometry,reverse transcriptase polymerase chain reaction andkaryotype analysis of the MSCs. Histopathology of lung,liver, kidneys, and regional lymph nodes ensured thebiomaterials biocompatibility.RESULTS: SSI remained negative throughout andindependently from treatment. Differences betweentreted groups in the severity of changes in WRL existed,showing a faster regeneration for PVA-CNTs-MSCs (P〈 0.05). At toe-off, less acute ankle joint angles wereseen for PVA-CNTs-MSCs group (P = 0.051) suggestingimproved ankle muscles function during the push offphase of the gait cycle. In PVA-PPy and PVA-CNTsgroups, there was a 25% and 42% increase of averagefiber area and a 13% and 21% increase of the "minimalFeret's diameter" respectively. Stereological analysisdisclosed a significantly (P 〈 0.05) increased myelinthickness (M), ratio myelin thickness/axon diameter (M/d) and ratio axon diameter/fiber diameter (d/D; g-ratio)in PVA-CNT-MSCs group (P 〈 0.05).CONCLUSION: Results revealed that treatmentwith MSCs and PVA-CNTs tube-guides induced betternerve fiber regeneration. Functional and kinematicsanalysis revealed positive synergistic effects brought byMSCs and PVA-CNTs. The PVA-CNTs and PVA-PPy arepromising scaffolds with electric

  4. Peanut cultivar selection for BLSS in terms of the biomass productivity, nutritional quality, photosynthetic character and mineral ions up-take by PTNDS cultivation

    Science.gov (United States)

    Liu, Hui; Wang, Minjuan; Fu, Yuming; Liu, Hong

    2016-11-01

    Peanut (Arachis hypogaea L.) has been selected as one of the crop candidates for BLSS, because its seeds have high nutritional value, being rich in vegetable oil and protein. Porous-Tube Nutrient Delivery System (PTNDS) has been successfully used for crop cultivation in controllable environments. In this paper, four peanut cultivars ('HY25', 'HY28', 'HY31' and 'BS1016') were evaluated in terms of yield, photosynthetic efficiency, insoluble fiber and ions uptake efficiency. Besides protein, total oil content and fatty acid composition were monitored in the seeds. 'HY25' plants showed much higher yield and harvest index, in addition to the lower lignin content of inedible biomass. Data showed that 'HY25' had the higher photosynthetic capacity of peanut leaves with regard to highest photosynthetic rate, qP and ΦPSII, lowest energy dissipation (qN) values, whereas instantaneous carboxylation efficiency and water use efficiency carotenoids content were no difference with the other cultivars. 'BS1016‧ showed the lowest photosynthetic capacity contrarily. These suggested that 'HY25‧ could be the most suitable for the cultivation in a closed controlled environment with PTNDS. While, both cations and anions except NH4+ and H2PO4-, were accumulated excessively compared to controls, especially with anions in PTNDS. Hence, further studies are needed in order to improve the nutritional quality of seeds and modify the fertilization strategy of this cultivar in the growth environment feasible during a closed environment and space mission.

  5. Fabrication of endothelial progenitor cell capture surface via DNA aptamer modifying dopamine/polyethyleneimine copolymer film

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xin; Deng, Jinchuan; Yuan, Shuheng; Wang, Juan; Luo, Rifang; Chen, Si [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu 610031 (China); School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China); Wang, Jin, E-mail: jinxxwang@263.net [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu 610031 (China); Huang, Nan [Key Lab. of Advanced Technology for Materials of Education Ministry, Southwest Jiaotong University, Chengdu 610031 (China); School of Material Science and Engineering, Southwest Jiaotong University, Chengdu 610031 (China)

    2016-11-15

    Highlights: • The dopamine/PEI film with controlled amine density was successfully prepared. • The DNA aptamer was assembled onto the film via electrostatic incorporation. • The A@DPfilmscanspecificallyandeffectivelycaptureEPCs. • The A@DP film can support the survival of ECs, control the hyperplasia of SMCs. • The dynamic/co-culture models are useful for studying cells competitive adhesion. - Abstract: Endothelial progenitor cells (EPCs) are mainly located in bone marrow and circulate, and play a crucial role in repairmen of injury endothelium. One of the most promising strategies of stents designs were considered to make in-situ endothelialization in vivo via EPC-capture biomolecules on a vascular graft to capture EPCs directly from circulatory blood. In this work, an EPC specific aptamer with a 34 bases single strand DNA sequence was conjugated onto the stent surface via dopamine/polyethyleneimine copolymer film as a platform and linker. The assembled density of DNA aptamer could be regulated by controlling dopamine percentage in this copolymer film. X-ray photoelectron spectroscopy (XPS), water contact angle (WCA) and fluorescence test confirmed the successful immobilization of DNA aptamer. To confirm its biofunctionality and cytocompatibility, the capturing cells ability of the aptamer modified surface and the effects on the growth behavior of human umbilical vein endothelial cells (HUVECs), smooth muscle cells (SMCs) were investigated. The aptamer functionalized sample revealed a good EPC-capture ability, and had a cellular friendly feature for both EPC and EC growth, while not stimulated the hyperplasia of SMCs. And, the co-culture experiment of three types of cells confirmed the specificity capturing of EPCs to aptamer modified surface, rather than ECs and SMCs. These data suggested that this aptamer functionalized surface may have a large potentiality for the application of vascular grafts with targeted endothelialization.

  6. Live-cell super-resolution imaging of intrinsically fast moving flagellates

    Science.gov (United States)

    Glogger, M.; Stichler, S.; Subota, I.; Bertlein, S.; Spindler, M.-C.; Teßmar, J.; Groll, J.; Engstler, M.; Fenz, S. F.

    2017-02-01

    Recent developments in super-resolution microscopy make it possible to resolve structures in biological cells at a spatial resolution of a few nm and observe dynamical processes with a temporal resolution of ms to μs. However, the optimal structural resolution requires repeated illumination cycles and is thus limited to chemically fixed cells. For live cell applications substantial improvement over classical Abbe-limited imaging can already be obtained in adherent or slow moving cells. Nonetheless, a large group of cells are fast moving and thus could not yet be addressed with live cell super-resolution microscopy. These include flagellate pathogens like African trypanosomes, the causative agents of sleeping sickness in humans and nagana in livestock. Here, we present an embedding method based on a in situ forming cytocompatible UV-crosslinked hydrogel. The fast cross-linking hydrogel immobilizes trypanosomes efficiently to allow microscopy on the nanoscale. We characterized both the trypanosomes and the hydrogel with respect to their autofluorescence properties and found them suitable for single-molecule fluorescence microscopy (SMFM). As a proof of principle, SMFM was applied to super-resolve a structure inside the living trypanosome. We present an image of a flagellar axoneme component recorded by using the intrinsic blinking behavior of eYFP. , which features invited work from the best early-career researchers working within the scope of J Phys D. This project is part of the Journal of Physics series’ 50th anniversary celebrations in 2017. Susanne Fenz was selected by the Editorial Board of J Phys D as an Emerging Talent/Leader.

  7. Chitosan/TiO2 composite membrane improves proliferation and survival of L929 fibroblast cells: Application in wound dressing and skin regeneration.

    Science.gov (United States)

    Behera, Sudhanshu Shekhar; Das, Urmimala; Kumar, Awanish; Bissoyi, Akalabya; Singh, Abhishek Kumar

    2017-05-01

    The microbial infection and growth of fibroblasts are the critical factors for the effective wound healing. The natural polymer-based dressing membranes may mimic extracellular matrix to support the survival, proliferation and differentiation of fibroblasts. The present study deals with the preparation of chitosan/titanium dioxide (CS/TiO2) composite membranes with different degree of TiO2 incorporation, and their characterization in terms of morphology, ultrastructure, thermal behavior and mechanical properties with SEM, FTIR, XRD and tensile strength analyses. The data demonstrated the formation of strong O-Ti-O bonding between TiO2 and CS resulting in superior porosity, mechanical strength, crystallinity and flexibility of the composite membranes. Further, the cyto-compatibility, proliferation, oxidative stress, cell cycle and apoptosis analyses of fibroblast L929 cells demonstrated the enhanced proliferation and survival, and decreased oxidative stress and apoptosis in L929 cells grown on CS/TiO2 membrane incorporated with 025% TiO2. Next, we measured the significant up-regulation in the expression of fibroblast-markers in L929 cells cultured on CS/TiO2 (0.25%) membrane. Furthermore, the CS/TiO2 composite membranes exhibited a superior antibacterial activity against Staphylococcus aureus. Taken together, the data confirmed that CS/TiO2 (0.25%) membrane improved the growth, survival and functional integrity of fibroblasts, and exerted antibacterial activity which may be utilized as potential dressing materials.

  8. Porous polymer scaffold for on-site delivery of stem cells--Protects from oxidative stress and potentiates wound tissue repair.

    Science.gov (United States)

    Geesala, Ramasatyaveni; Bar, Nimai; Dhoke, Neha R; Basak, Pratyay; Das, Amitava

    2016-01-01

    Wound healing by cell transplantation techniques often suffer setbacks due to oxidative stress encountered at injury sites. A porous polyethyleneglycol-polyurethane (PEG-PU) scaffold that facilitates cell delivery and boosts tissue repair was developed through semi-interpenetrating polymer network approach. The key physico-chemical properties assessed confirms these polymeric matrices are highly thermostable, barostable, degrade at an acidic pH (5.8), biodegradable, cytocompatible and possess excellent porosity. Mechanism of cellular penetration into porous polymer networks was evident by a ≥6 - fold increase in gene expression of MMP-13 and MMP-2 via activation of Akt and Erk. H2O2-induced apoptosis of mouse bone marrow stem cells (BMSCs) was abrogated in presence of polymer networks indicating a protective effect from oxidative stress. Transplantation of BMSC + PEG-PU at murine excisional splint wound site depicted significant increase in fibroblast proliferation, collagen deposition, anti-oxidant enzyme activities of catalase, SOD and GPx. Furthermore it significantly decreased expression of pro-inflammatory cytokines (IL-1β, TNF-α, IL-8, etc) with a concomitant increase in anti-inflammatory cytokines (IL-10, IL-13) at an early healing period of day 7. Finally, immunostaining revealed an enhanced engraftment and vascularity indicating an accelerated wound tissue closure. This pre-clinical study demonstrates the proof-of-concept and further necessitates their clinical evaluation as potential cell delivery vehicle scaffolds.

  9. Cytocompatibility of oxygen plasma-treated polylactic acid and bioactive glass guided bone regeneration membrane%氧等离子处理聚乳酸与生物活性玻璃引导骨再生膜的细胞相容性

    Institute of Scientific and Technical Information of China (English)

    齐磊; 同志超; 伍骥

    2015-01-01

    BACKGROUND:Currently, bioactive glass and polylactic acid have been used in clinical dentistry and plastic surgery; however, their therapeutic outcomes are not satisfactory, because the material properties have some limitations. OBJECTIVE:To explore the cytocompatibility of oxygen plasma-treated polylactic acid and bioactive glass guided bone regeneration membrane. METHODS:Bioactive glass and polylactic acid were used as the basic materials to prepare polylactic acid membrane, polylactic acid and bioactive glass composite membrane and oxygen plasme-treated polylactic acid and bioactive glass composite membrane, al of which were used to culture MG63 cels. Cel adhesion rate, cel proliferation rate and alkaline phosphatase activity of MG63 cels on these three kinds of membranes were observed. RESULTS AND CONCLUSION: With the growth of time, in these three groups of membranes, the cel adhesion rate and cel proliferation rate were al significantly increased. Alkaline phosphatase activity showed a decreasing trend after the first increase, and reached its peak at the 7thday of culture. The cel adhesion rate and cel proliferation rate in oxygen plasma-treated polylactic acid and bioactive glass group were significantly higher than those in the other two groups, while the cel adhesion and proliferation rates in polylactic acid and polylactic acid and bioactive glass groups were similar. At the 3rd day of culture, the alkaline phosphatase activity in the polylactic acid and bioactive glass group and oxygen plasma-treated polylactic acid and bioactive glass group was significantly higher than that in the polylactic acid group. At the 7th and 14th days, there was no significant difference in the alkaline phosphatase activity among these three groups. These results show that oxygen plasma-treated polylactic acid and bioactive glass composite membrane has good biocompatibility, which can better promote cel adhesion, proliferation and matrix secretion from osteogenic cels.%背

  10. Biocompatibility Properties of Polyamide 6/ PCL Blends Composite Textile Scaffold using EA.hy926 Human Endothelial Cells.

    Science.gov (United States)

    Abdal-Hay, Abdalla; Abdelrazek Khalil, Khalil; Al-Jassir, Fawzi F; Gamal-Eldeen, Amira

    2017-02-27

    Enhancing the cytocompatibility profiles including cell attachment, growth and viability of designed synthetic scaffolds have a pivotal role in tissue engineering applications. Polymer blending is one of the most effective methods for providing new desirable biomaterials for tissue scaffolds. This article reports a novel polyamide 6/ poly(Ɛ-caprolactone) (PA6/PCL) blends solution by varying the concentrations ratios of PA6 and PCL which was fabricated to create composite fibrous tissue scaffolds. Highly porous blends fibrous scaffold has been fabricated and their suitability as cell-support for EA.hy926 human endothelial cells has been studied. Our results demonstrated that the unique nanoscale morphological properties and tune porosity of the blends scaffold were controlled. We found that these properties are mainly depending on the PA6/PCL blending viscosity value, and the viscosity of the blending solution has an intense effect on the properties of the blends scaffold. The influence of the scaffolds extraction fluids and the scaffold direct contact of both of the metabolic viability and the DNA integrity of EA.hy926 endothelial cells as well as the cell/ scaffold interaction analysis by Scanning Electron Microscope, after different co-culturing intervals, demonstrated that PA6/PCL blend scaffolds showed different behavior. Blend scaffolds of PA6/PCL of 90:10 ratio proved to be excellent endothelial cell carrier, which provided a good cell morphology, DNA integrity and viability, induced DNA synthesis/replication, and enhanced cell proliferation, attachment, and invasion. These results indicate that blends of PA6/PCL composite fibers is a promising 3D substitute for the next generation of synthetic tissue scaffold that could soon find clinical applications.

  11. Adapting biodegradable oligo(poly(ethylene glycol) fumarate) hydrogels for pigment epithelial cell encapsulation and lens regeneration.

    Science.gov (United States)

    Zhang, Mimi W; Park, Hansoo; Guo, Xuan; Nakamura, Kenta; Raphael, Robert M; Kasper, F Kurtis; Mikos, Antonios G; Tsonis, Panagiotis A

    2010-04-01

    This study investigated the encapsulation of newt iris pigment epithelial cells (PECs), which have the ability to regenerate a lens by trans-differentiation in vivo, within a biodegradable hydrogel of oligo(poly(ethylene glycol) fumarate) crosslinked with poly(ethylene glycol)-diacrylate. Hydrogel beads of initial diameter of 1 mm were fabricated by a molding technique. The swelling ratio and degradation rate of the hydrogel beads decreased with increasing crosslinking ratios. Confocal microscopy confirmed the cytocompatibility of crosslinking hydrogel formulations as evidenced by the viability of an encapsulated model cell line within a crosslinked hydrogel bead. Hydrogel beads encapsulating iris PECs were also implanted into lentectomized newts in vivo; histological evaluation of explants after 30 days revealed a regenerated lens, thus demonstrating that the presence of degrading hydrogel did not adversely affect lens regeneration. The results of this study suggest the potential of a method for lens regeneration involving oligo(poly(ethylene glycol) fumarate) hydrogels for iris PEC encapsulation and transplantation.

  12. Synergistic acceleration in the osteogenic and angiogenic differentiation of human mesenchymal stem cells by calcium silicate-graphene composites.

    Science.gov (United States)

    Shie, Ming-You; Chiang, Wei-Hung; Chen, I-Wen Peter; Liu, Wen-Yi; Chen, Yi-Wen

    2017-04-01

    Recent exciting findings of the biological interactions of graphene materials have shed light on potential biomedical applications of graphene-containing composites. Owing to the superior mechanical properties and low coefficient of thermal expansion, graphene has been widely used in the reinforcement of biocomposites. In the present study, various ratios of graphene (0.25wt%, 0.5wt% and 1.0wt%) were reinforced into calcium silicate (CS) for bone graft application. Results show that the graphene was embedded in the composites homogeneously. Adding 1wt% graphene into CS increased the young's modulus by ~47.1%. The formation of bone-like apatite on a range of composites with graphene weight percentages ranging from 0 to 1 has been investigated in simulated body fluid. The presence of a bone-like apatite layer on the composites surface after immersion in simulated body fluid was considered by scanning electron microscopy. In vitro cytocompatibility of the graphene-contained CS composites was evaluated using human marrow stem cells (hMSCs). The proliferation and alkaline phosphatase, osteopontin and osteocalcin osteogenesis-related protein expression of the hMSCs on the 1wt% graphene-contained specimens showed better results than on the pure CS. In addition, the angiogenesis-related protein (vWF and ang-1) secretion of cells was significantly stimulated when the graphene concentration in the composites was increased. These results suggest that graphene-contained CS bone graft are promising materials for bone tissue engineering applications.

  13. Fabrication, bioactivity, in vitro cytotoxicity and cell viability of cryo-treated nanohydroxyapatite–gelatin–polyvinyl alcohol macroporous scaffold

    Directory of Open Access Journals (Sweden)

    Sanjaya Kumar Swain

    2014-09-01

    Full Text Available Freeze casting and cryogenic treatment both low temperature process have been employed to fabricate nanobiocomposite hydroxyapatite (HA–gelatin–polyvinyl alcohol (PVA macroporous scaffolds from synthesized three different spherical, rod and fibrous HA nanoparticles and composition optimized vis-á-vis porosity architecture, content and compressive strength. A critical HA morphology, solid loading and liquid nitrogen interaction time have a significant effect to enhance the mechanical response of developed scaffolds. Cryo-treated 40 wt.% nanorod HA–gelatin–PVA scaffold posses interconnected pore structure with 80 vol.% porosity, average pore diameter 50–200 μm and highest 5.8 MPa compressive strength. Different degree of the apatite deposition phenomenon in simulated body fluid solution at 37 °C and pH ∼ 7.4 varies with respect to time. In vitro cytotoxicity and L929 mouse fibroblast cell culture in the presence of Dulbecco's Modified Eagle Medium and 10% Fetal Bovine Serum at 37 °C and 5% CO2 atmosphere exhibit excellent cytocompatibility and cell viability at low extract concentration up to 25%.

  14. Experimental Study on Silk Protein- Three-dimensional Gelatin Scaffold and Compatibility of Liver Cells%蚕丝蛋白和明胶复合组织工程材料与肝细胞相容性的实验研究

    Institute of Scientific and Technical Information of China (English)

    徐丽莎; 刘文晶; 申少波; 杨照; 陈蕊蕊; 韩英; 尹芳; 时永全; 周新民

    2011-01-01

    Objective: To study the silk fibroin material's effect on proliferation of human normal hepatic cell line QZG,and to testify the cytocompatibility when blending of silk fibroin and gelatin into 3D scaffold. Methods:The activity of cell proliferation and relative growth rate (RGR) were assessed by MTT colorimetric assay and viable cell counting, The effect of silk protein materials on growth of cells was observed by scanning electron microscopy (SEM). Results: Human normal hepatic cell line QZG were cultivated in vitro directly on pure silk protein materials and silk fibroin/gelatin materials. Cells solidly adhered to the materials. The activity of cell proliferation on silk fibroin/gelatin materials was significantly more than that in the group of pure silk fibroin materials. The result of viable cell counting was compatible to MTT colorimetric assay. Conclusion:The silk fibroin materials together with gelatin has a good cytocompatibility with human normal hepatic cell line QZG. It will be useful in liver tissue engineering.%目的:研究蚕丝蛋白-明胶三维材料支架对人永生化肝细胞系QZG 贴附及增殖的影响.方法:采用四氮唑盐比色法(MTT)、细胞计数法检测QZG 细胞在纯蚕丝生物材料上与在蚕丝蛋白-明胶复合材料上的增殖情况,用扫描电镜观察QZG细胞在两种三维生物材料上的贴附与增殖情况.结果:QZG细胞可以在蚕丝蛋白生物材料贴附及增殖.在引入明胶的蚕丝蛋白材料上细胞贴附更紧密,增殖更明显.结论:蚕丝蛋白与明胶复合材料支架具有良好的细胞贴附性能.通过改进在肝组织工程应用方面将具有一定应用前景.

  15. Effect of physicochemical properties of a cement based on silicocarnotite/calcium silicate on in vitro cell adhesion and in vivo cement degradation.

    Science.gov (United States)

    Aparicio, Julia Lucas; Rueda, Carmen; Manchón, Ángel; Ewald, Andrea; Gbureck, Uwe; Alkhraisat, Mohammad Hamdan; Jerez, Luis Blanco; Cabarcos, Enrique López

    2016-08-02

    A silicon calcium phosphate cement (Si-CPC) was developed to produce a composite of calcium phosphate and calcium silicate. The silicon cements prepared with low silicon (Si) content were composed of crystalline phases of brushite and silicocarnotite. However, the cements prepared with high Si content were mainly composed of amorphous phases of silicocarnotite, hydroxyapatite and calcium silicate. The cement porosity was about 40% with a shift of the average pore diameter to the nanometric range with increasing Si content. Interestingly, this new cement system provides a matrix with a high specific surface area of up to 29 m(2) g(-1). The cytocompatibility of the new Si-doped cements was tested with a human osteoblast-like cell line (MG-63) showing an enhancement of cell proliferation (up to threefold) when compared with unsubstituted material. Cements with a high silica content also improved the cell attachment. The in vivo results indicated that Si-CPCs induce the formation of new bone tissue, and modify cement resorption. We conclude that this cement provides an optimal environment to enhance osteoblast growth and proliferation that could be of interest in bone engineering.

  16. Effect of an Experimental Direct Pulp-capping Material on the Properties and Osteogenic Differentiation of Human Dental Pulp Stem Cells

    Science.gov (United States)

    Yu, Fan; Dong, Yan; Yang, Yan-Wei; Lin, Ping-Ting; Yu, Hao-Han; Sun, Xiang; Sun, Xue-Fei; Zhou, Huan; Huang, Li; Chen, Ji-Hua

    2016-10-01

    Effective pulp-capping materials must have antibacterial properties and induce dentin bridge formation; however, many current materials do not satisfy clinical requirements. Accordingly, the effects of an experiment pulp-capping material (Exp) composed of an antibacterial resin monomer (MAE-DB) and Portland cement (PC) on the viability, adhesion, migration, and differentiation of human dental pulp stem cells (hDPSCs) were examined. Based on a Cell Counting Kit-8 assay, hDPSCs exposed to Exp extracts showed limited viability at 24 and 48 h, but displayed comparable viability to the control at 72 h. hDPSC treatment with Exp extracts enhanced cellular adhesion and migration according to in vitro scratch wound healing and Transwell migration assays. Exp significantly upregulated the expression of osteogenesis-related genes. The hDPSCs cultured with Exp exhibited higher ALP activity and calcium deposition in vitro compared with the control group. The novel material showed comparable cytocompatibility to control cells and promoted the adhesion, migration, and osteogenic differentiation of hDPSCs, indicating excellent biocompatibility. This new direct pulp-capping material containing MAE-DB and PC shows promise as a potential alternative to conventional materials for direct pulp capping.

  17. Effect of an Experimental Direct Pulp-capping Material on the Properties and Osteogenic Differentiation of Human Dental Pulp Stem Cells

    Science.gov (United States)

    Yu, Fan; Dong, Yan; Yang, Yan-wei; Lin, Ping-ting; Yu, Hao-han; Sun, Xiang; Sun, Xue-fei; Zhou, Huan; Huang, Li; Chen, Ji-hua

    2016-01-01

    Effective pulp-capping materials must have antibacterial properties and induce dentin bridge formation; however, many current materials do not satisfy clinical requirements. Accordingly, the effects of an experiment pulp-capping material (Exp) composed of an antibacterial resin monomer (MAE-DB) and Portland cement (PC) on the viability, adhesion, migration, and differentiation of human dental pulp stem cells (hDPSCs) were examined. Based on a Cell Counting Kit-8 assay, hDPSCs exposed to Exp extracts showed limited viability at 24 and 48 h, but displayed comparable viability to the control at 72 h. hDPSC treatment with Exp extracts enhanced cellular adhesion and migration according to in vitro scratch wound healing and Transwell migration assays. Exp significantly upregulated the expression of osteogenesis-related genes. The hDPSCs cultured with Exp exhibited higher ALP activity and calcium deposition in vitro compared with the control group. The novel material showed comparable cytocompatibility to control cells and promoted the adhesion, migration, and osteogenic differentiation of hDPSCs, indicating excellent biocompatibility. This new direct pulp-capping material containing MAE-DB and PC shows promise as a potential alternative to conventional materials for direct pulp capping. PMID:27698421

  18. Efficient delivery of C/EBP beta gene into human mesenchymal stem cells via polyethylenimine-coated gold nanoparticles enhances adipogenic differentiation

    Science.gov (United States)

    Joydeep, Das; Choi, Yun-Jung; Yasuda, Hideyo; Han, Jae Woong; Park, Chankyu; Song, Hyuk; Bae, Hojae; Kim, Jin-Hoi

    2016-01-01

    The controlled differentiation of stem cells via the delivery of specific genes encoding appropriate differentiation factors may provide useful models for regenerative medicine and aid in developing therapies for human patients. However, the majority of non-viral vectors are not efficient enough to manipulate difficult-to-transfect adult human stem cells in vitro. Herein, we report the first use of 25 kDa branched polyethylenimine-entrapped gold nanoparticles (AuPEINPs) and covalently bound polyethylenimine-gold nanoparticles (AuMUAPEINPs) as carriers for efficient gene delivery into human mesenchymal stem cells (hMSCs). We determined a functional application of these nanoparticles by transfecting hMSCs with the C/EBP beta gene, fused to EGFP, to induce adipogenic differentiation. Transfection efficacy with AuPEINPs and AuMUAPEINPs was 52.3% and 40.7%, respectively, which was 2.48 and 1.93 times higher than that by using Lipofectamine 2000. Luciferase assay results also demonstrated improved gene transfection efficiency of AuPEINPs/AuMUAPEINPs over Lipofectamine 2000 and polyethylenimine. Overexpression of exogenous C/EBP beta significantly enhanced adipogenesis in hMSCs as indicated by both of Oil Red O staining and mRNA expression analyses. Nanoparticle/DNA complexes exhibited favorable cytocompatibility in hMSCs. Taken together, AuPEINPs and AuMUAPEINPs potentially represent safe and highly efficient vehicles for gene delivery to control hMSC differentiation and for therapeutic gene delivery applications. PMID:27677463

  19. Anticoagulation and endothelial cell behaviors of heparin-loaded graphene oxide coating on titanium surface.

    Science.gov (United States)

    Pan, Chang-Jiang; Pang, Li-Qun; Gao, Fei; Wang, Ya-Nan; Liu, Tao; Ye, Wei; Hou, Yan-Hua

    2016-06-01

    Owing to its unique physical and chemical properties, graphene oxide (GO) has attracted tremendous interest in many fields including biomaterials and biomedicine. The purpose of the present study is to investigate the endothelial cell behaviors and anticoagulation of heparin-loaded GO coating on the titanium surface. To this end, the titanium surface was firstly covered by the polydopamine coating followed by the deposition of the GO coating. Heparin was finally loaded on the GO coating to improve the blood compatibility. The results of attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) indicated that the heparin-loaded GO coating was successfully created on the titanium surface. The scanning electron microscopy (SEM) images indicated that a relative uniform GO coating consisting of multilayer GO sheets was formed on the substrate. The hydrophilicity of the titanium surface was enhanced after the deposition of GO and further improved significantly by the loading heparin. The GO coating can enhance the endothelial cell adhesion and proliferation as compared with polydopamine coating and the blank titanium. Loading heparin on the GO coating can significantly reduce the platelet adhesion and prolong the activated partial thromboplastin time (APTT) while not influence the endothelial cell adhesion and proliferation. Therefore, the heparin-loaded GO coating can simultaneously enhance the cytocompatibility to endothelial cells and blood compatibility of biomaterials. Because the polydopamine coating can be easily prepared on most of biomaterials including polymer, ceramics and metal, thus the approach of the present study may open up a new window of promising an effective and efficient way to promote endothelialization and improve the blood compatibility of blood-contact biomedical devices such as intravascular stents.

  20. In Vitro Response of Retinal Pigment Epithelial Cells Exposed to Chitosan Materials Prepared with Different Cross-Linkers

    Directory of Open Access Journals (Sweden)

    Jui-Yang Lai

    2010-12-01

    Full Text Available The interaction between cells and biopolymers is the evaluation indicator of the biocompatibility of materials. The purpose of this work was to examine the responses of retinal pigment epithelial (RPE cells to genipin (GP or glutaraldehyde (GTA cross-linked chitosan by means of cell viability assays, cytokine expression analyses, and apoptosis assays. Evaluations of non-cross-linked chitosan were conducted simultaneously for comparison. Both GP and GTA treated samples with the same extent of cross-linking (around 80% were prepared by varying cross-linking time. Our results showed that GP cross-linking was carried out by either radical polymerization of the monomers or SN2 nucleophilic substitution reaction involving the replacement of the ester group on the monomer with a secondary amide linkage. On the other hand, GTA could react with free amino groups of chitosan, leading to the formation of either the Schiff bases or the Michael-type adducts with terminal aldehydes. The biocompatibility of non-cross-linked chitosan membranes was demonstrated by the absence of any signs of toxicity or inflammation reaction. The present study showed that the ARPE-19 cells exposed to GTA cross-linked chitosan membranes had significantly higher cytotoxicity, interleukin-6 levels, and number of TUNEL-positive nuclei than did those exposed to GP treated samples. In addition, the materials modified with GTA trigger apoptosis at an early stage and may induce toxicity in the RPE cells later. The findings suggest that while the chitosan molecules bridged by GP are satisfactorily cytocompatible, the counterparts treated by GTA do not seem to be tolerated. In terms of material safety, the GP cross-linked chitosan may be compatible with human RPE cells and may have a potential application as delivery carriers in the treatment of posterior segment diseases.

  1. Effects of carbon nanotubes in a chitosan/collagen-based composite on mouse fibroblast cell proliferation.

    Science.gov (United States)

    Zhao, Wen; Yu, Wenwen; Zheng, Jiawei; Wang, Ying; Zhang, Zhiyuan; Zhang, Dongsheng

    2014-01-01

    This study investigated the in vitro cytocompatibility of carbon nanotubes (CNTs) in a chitosan/collagen-based composite. Mouse fibroblasts were cultured on the surface of a novel material consisting of CNTs in a chitosan/collagen-based composite (chitosan/collagen+CNTs group). Chitosan/collagen composites without CNTs served as the control material (chitosan/collagen group) and cells cultured normally in tissue culture plates served as blank controls (blank control group). Cell adhesion and proliferation were observed, and cell apoptosis was measured. The doubling time (DT1) of cells was significantly shorter in the chitosan/collagen+CNTs group than in the chitosan/collagen group, and that in the chitosan/collagen group was shorter than in the blank control group. The CNTs in the chitosan/collagen-based composites promoted mouse fibroblast adhesion, producing a distinct cytoskeletal structure. At 24 h after culture, the cytoskeleton of the cells in the chitosan/collagen+CNTs group displayed typical fibroblastic morphology, with clear microfilaments. Cells in the chitosan/collagen group were typically round, with an unclear cytoskeleton. The blank control group even had a few unattached cells. At 4 days after incubation, no early apoptosis of cells was detected in the blank control group, whereas early apoptosis of cells was observed in the chitosan/collagen+CNTs and chitosan/collagen groups. No significant difference in the proportion of living cells was detected among the three groups. After entering the plateau stage, the average cell number in the chitosan/collagen+CNTs group was similar to that in the chitosan/collagen group and significantly smaller than that in the blank control group. Early apoptosis of cells in the blank control group was not detectable. There were significant differences in early apoptosis among the three groups. These results suggest that CNTs in a chitosan/collagen-based composite did not cause significant cytotoxic effects on mouse

  2. Characterization and anticancer potential of ferulic acid-loaded chitosan nanoparticles against ME-180 human cervical cancer cell lines

    Science.gov (United States)

    Panwar, Richa; Sharma, Asvene K.; Kaloti, Mandeep; Dutt, Dharm; Pruthi, Vikas

    2016-08-01

    Ferulic acid (FA) is a widely distributed hydroxycinnamic acid found in various cereals and fruits exhibiting potent antioxidant and anticancer activities. However, due to low solubility and permeability, its availability to biological systems is limited. Non-toxic chitosan-tripolyphosphate pentasodium (CS-TPP) nanoparticles (NPs) are used to load sparingly soluble molecules and drugs, increasing their bioavailability. In the present work, we have encapsulated FA into the CS-TPP NPs to increase its potential as a therapeutic agent. Different concentrations of FA were tested to obtain optimum sized FA-loaded CS-TPP nanoparticles (FA/CS-TPP NPs) by ionic gelation method. Nanoparticles were characterized by scanning electron microscopy, Fourier transformation infrared spectroscopy (FTIR), thermogravimetric analyses and evaluated for their anticancer activity against ME-180 human cervical cancer cell lines. The FTIR spectra confirmed the encapsulation of FA and thermal analysis depicted its degradation profile. A concentration-dependent relationship between FA encapsulation efficiency and FA/CS-TPP NPs diameter was observed. Smooth and spherical FA-loaded cytocompatible nanoparticles with an average diameter of 125 nm were obtained at 40 µM FA conc. The cytotoxicity of 40 µM FA/CS-TPP NPs against ME-180 cervical cancer cell lines was found to be higher as compared to 40 µM native FA. Apoptotic morphological changes as cytoplasmic remnants and damaged wrinkled cells in ME-180 cells were visualized using scanning electron microscopic and fluorescent microscopic techniques. Data concluded that chitosan enveloped FA nanoparticles could be exploited as an excellent therapeutic drug against cancer cells proliferation.

  3. Preparation, characterisation, and in vitro evaluation of electrically conducting poly(ɛ-caprolactone)-based nanocomposite scaffolds using PC12 cells.

    Science.gov (United States)

    Gopinathan, Janarthanan; Quigley, Anita F; Bhattacharyya, Amitava; Padhye, Rajiv; Kapsa, Robert M I; Nayak, Rajkishore; Shanks, Robert A; Houshyar, Shadi

    2016-04-01

    In the current study, we describe the synthesis, material characteristics, and cytocompatibility of conducting poly (ɛ-caprolactone) (PCL)-based nano-composite films. Electrically conducting carbon nano-fillers (carbon nano-fiber (CNF), nano-graphite (NG), and liquid exfoliated graphite (G)) were used to prepare porous film type scaffolds using modified solvent casting methods. The electrical conductivity of the nano-composite films was increased when carbon nano-fillers were incorporated in the PCL matrix. CNF-based nano-composite films showed the highest increase in electrical conductivity. The presence of an ionic solution significantly improved the conductivity of some of the polymers, however at least 24 h was required to absorb the simulated ion solutions. CNF-based nano-composite films were found to have good thermo-mechanical properties compared to other conducting polymer films due to better dispersion and alignment in the critical direction. Increased nano-filler content increased the crystallisation temperature. Analysis of cell viability revealed no increase in cell death on any of the polymers compared to tissue culture plastic controls, or compared to PCL polymer without nano-composites. The scaffolds showed some variation when tested for PC12 cell attachment and proliferation, however all the polymers supported PC12 attachment and differentiation in the absence of cell adhesion molecules. In general, CNF-based nano-composite films with highest electrical conductivity and moderate roughness showed highest cell attachment and proliferation. These polymers are promising candidates for use in neural applications in the area of bionics and tissue engineering due to their unique properties.

  4. Stem Cells

    Science.gov (United States)

    Stem cells are cells with the potential to develop into many different types of cells in the body. ... the body. There are two main types of stem cells: embryonic stem cells and adult stem cells. Stem ...

  5. Mg ion implantation on SLA-treated titanium surface and its effects on the behavior of mesenchymal stem cell

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Beom-Su; Kim, Jin Seong [Wonkwang Bone Regeneration Research Institute, Wonkwang University, Iksan 570-749 (Korea, Republic of); Bonecell Biotech Inc., 77, Dunsan-ro, Seo-gu, Daejeon 302-830 (Korea, Republic of); Park, Young Min [DIO Corporation, 66, Centum seo-ro, Haeundae-gu, Busan (Korea, Republic of); Choi, Bo-Young [Department of Oral and maxillofacial Surgery, Wonkwang University Daejeon Dental Hospital, Daejeon 302-830 (Korea, Republic of); Lee, Jun, E-mail: omslee@wku.ac.kr [Wonkwang Bone Regeneration Research Institute, Wonkwang University, Iksan 570-749 (Korea, Republic of); Bonecell Biotech Inc., 77, Dunsan-ro, Seo-gu, Daejeon 302-830 (Korea, Republic of)

    2013-04-01

    Magnesium (Mg) is one of the most important ions associated with bone osseointegration. The aim of this study was to evaluate the cellular effects of Mg implantation in titanium (Ti) surfaces treated with sand blast using large grit and acid etching (SLA). Mg ions were implanted into the surface via vacuum arc source ion implantation. The surface morphology, chemical properties, and the amount of Mg ion release were evaluated by scanning electron microscopy (SEM), Auger electron spectroscopy (AES), Rutherford backscattering spectroscopy (RBS), and inductively coupled plasma-optical emission spectrometer (ICP-OES). Human mesenchymal stem cells (hMSCs) were used to evaluate cellular parameters such as proliferation, cytotoxicity, and adhesion morphology by MTS assay, live/dead assay, and SEM. Furthermore, osteoblast differentiation was determined on the basis of alkaline phosphatase (ALP) activity and the degree of calcium accumulation. In the Mg ion-implanted disk, 2.3 × 10{sup 16} ions/cm{sup 2} was retained. However, after Mg ion implantation, the surface morphology did not change. Implanted Mg ions were rapidly released during the first 7 days in vitro. The MTS assay, live/dead assay, and SEM demonstrated increased cell attachment and growth on the Mg ion-implanted surface. In particular, Mg ion implantation increased the initial cell adhesion, and in an osteoblast differentiation assay, ALP activity and calcium accumulation. These findings suggest that Mg ion implantation using the plasma source ion implantation (PSII) technique may be useful for SLA-treated Ti dental implants to improve their osseointegration capacity. - Highlights: ► Mg ion was coated onto surface of SLA treated titanium via vacuum arc source ion implantation method. ► The morphological characteristics did not change after Mg ion implantation. ► Mg ion implanted SLA Ti is highly cytocompatible. ► Initial cell adhesion of MSCs is improved by Mg ion implantation. ► Mg ion implantation

  6. In vitro investigation of a tissue-engineered cell-tendon complex mimicking the transitional architecture at the ligament-bone interface.

    Science.gov (United States)

    Wang, Zhibing; Zhang, Yuan; Zhu, Jie; Dong, Shiwu; Jiang, Tao; Zhou, Yue; Zhang, Xia

    2015-03-01

    Restoration of the transitional ligament-bone interface is critical for graft-bone integration. We postulated that an allogenic scaffold mimicking the fibrogenic, chondrogenic, and osteogenic transition gradients could physiologically promote ligament-bone incorporation. The aim of this study was to construct and characterize a composite tendon scaffold with a continuous and heterogeneous transition region mimicking a native ligament insertion site. Genetically modified heterogeneous cell populations were seeded within specific regions of decellularized rabbit Achilles tendons to fabricate a stratified scaffold containing three biofunctional regions supporting fibrogenesis, chondrogenesis, and osteogenesis. The observed morphology, architecture, cytocompatibility, and biomechanics of the scaffolds demonstrated their improved bio-physico-chemical properties. The formation of the transitional regions was augmented via enhanced delivery of two transcription factors, sex determining region Y-box 9 and runt-related transcription factor 2, which also triggered early up-regulated expression of cartilage- and bone-relevant markers, according to quantitative PCR and immunoblot analyses. Gradient tissue-specific matrix formation was also confirmed within the predesignated regions via histological staining and immunofluorescence assays. These results suggest that a transitional interface could be replicated on an engineered tendon through stratified tissue integration. The scaffold offers the advantages of a multitissue transition involving controlled cellular interactions and matrix heterogeneity, which can be applied for the regeneration of the ligament-bone interface.

  7. Influence of the addition of β-TCP on the morphology, thermal properties and cell viability of poly (lactic acid) fibers obtained by electrospinning.

    Science.gov (United States)

    Siqueira, L; Passador, F R; Costa, M M; Lobo, A O; Sousa, E

    2015-01-01

    Electrospinning is a simple and low-cost way to fabricate fibers. Among the various polymers used in electrospinning process, the poly (lactic acid) (PLA) stands out due to its excellent biodegradability and biocompatibility. Calcium phosphate ceramics has been recognized as an attractive biomaterial because their chemical composition is similar to the mineral component of the hard tissue in the body. Furthermore, they are bioactive and osteoinductive and some are even quite biodegradable. The beta-tricalcium phosphate (β-TCP) particles were synthesized by solid state reaction. Different contents of β-TCP particles were incorporated in polymer matrices to form fibers of PLA/β-TCP composites by electrospinning aiming a possible application as a scaffold for tissue engineering. The fibers were characterized by scanning electron microscopy (SEM), infrared (FTIR), differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). The average diameter of the fibers varied in the range of 260-519.6 ± 50 nm. The presence of β-TCP particles promoted changes on thermal properties of the fibers. The composite with 8 wt-% of β-TCP showed a low degree of crystallinity and can be used for application in tissue engineering. The cell viability was analyzed by reduction of the methyl tetrazolium salt by the pyruvate dehydrogenase enzymatic complex present in the matrix of mitochondria (MTT test). All PLA fiber groups, with different contents of β-TCP, showed cytocompatibility ability with non-cytotoxicity effect and bioactive properties using SBF assay.

  8. Performance of polymer nano composite membrane electrode assembly using Alginate as a dopant in polymer electrolyte membrane fuel cell

    Science.gov (United States)

    Mulijani, S.

    2016-11-01

    Polymer membrane and composite polymer for membrane electrode assembly (MEAs) are synthesized and studied for usage in direct methanol fuel cell (DMFC). In this study, we prepared 3 type of MEAs, polystyrene (PS), sulfonated polystyrene (SPS) and composite polymer SPS-alginat membrane via catalyst hot pressed method. The performance and properties of prepared MEAs were evaluated and analyzed by impedance spectrometry and scanning electron microscopy (SEM). The result showed that, water up take of MEA composite polymer SPS-alginate was obtained higher than that in SPS and PS. The proton conductivity of MEA-SPS-alginate was also higher than that PS and PSS. SEM characterization revealed that the intimate contact between the carbon catalyst layers (CL) and the membranes, and the uniformly porous structure correlate positively with the MEAs prepared by hot pressed method, exhibiting high performances for DMFC.

  9. Performance of polymer nano composite membrane electrode assembly using Alginate as a dopant in polymer electrolyte membrane fuel cell

    Science.gov (United States)

    Mulijani, S.

    2017-01-01

    Polymer membrane and composite polymer for membrane electrode assembly (MEAs) are synthesized and studied for usage in direct methanol fuel cell (DMFC). In this study, we prepared 3 type of MEAs, polystyrene (PS), sulfonated polystyrene (SPS) and composite polymer SPS-alginat membrane via catalyst hot pressed method. The performance and properties of prepared MEAs were evaluated and analyzed by impedance spectrometry and scanning electron microscopy (SEM). The result showed that, water up take of MEA composite polymer SPS-alginate was obtained higher than that in SPS and PS. The proton conductivity of MEA-SPS-alginate was also higher than that PS and PSS. SEM characterization revealed that the intimate contact between the carbon catalyst layers (CL) and the membranes, and the uniformly porous structure correlate positively with the MEAs prepared by hot pressed method, exhibiting high performances for DMFC.

  10. Nanocrystalline spherical hydroxyapatite granules for bone repair: in vitro evaluation with osteoblast-like cells and osteoclasts.

    Science.gov (United States)

    Bernhardt, A; Dittrich, R; Lode, A; Despang, F; Gelinsky, M

    2013-07-01

    Conventionally sintered hydroxyapatite-based materials for bone repair show poor resorbability due to the loss of nanocrystallinity. The present study describes a method to establish nanocrystalline hydroxyapatite granules. The material was prepared by ionotropic gelation of an alginate sol containing hydroxyapatite (HA) powder. Subsequent thermal elimination of alginate at 650 °C yielded non-sintered, but unexpectedly stable hydroxyapatite granules. By adding stearic acid as an organic filler to the alginate/HA suspension, the granules exhibited macropores after thermal treatment. A third type of material was achieved by additional coating of the granules with silica particles. Microstructure and specific surface area of the different materials were characterized in comparison to the already established granular calcium phosphate material Cerasorb M(®). Cytocompatibility and potential for bone regeneration of the materials was evaluated by in vitro examinations with osteosarcoma cells and osteoclasts. Osteoblast-like SaOS-2 cells proliferated on all examined materials and showed the typical increase of alkaline phosphatase (ALP) activity during cultivation. Expression of bone-related genes coding for ALP, osteonectin, osteopontin, osteocalcin and bone sialoprotein II on the materials was proven by RT-PCR. Human monocytes were seeded onto the different granules and osteoclastogenesis was examined by activity measurement of tartrate-specific acid phosphatase (TRAP). Gene expression analysis after 23 days of cultivation revealed an increased expression of osteoclast-related genes TRAP, vitronectin receptor and cathepsin K, which was on the same level for all examined materials. These results indicate, that the nanocrystalline granular materials are of clinical interest, especially for bone regeneration.

  11. Cell protective, ABC triblock polymer-based thermoresponsive hydrogels with ROS-triggered degradation and drug release.

    Science.gov (United States)

    Gupta, Mukesh K; Martin, John R; Werfel, Thomas A; Shen, Tianwei; Page, Jonathan M; Duvall, Craig L

    2014-10-22

    A combination of anionic and RAFT polymerization was used to synthesize an ABC triblock polymer poly[(propylenesulfide)-block-(N,N-dimethylacrylamide)-block-(N-isopropylacrylamide)] (PPS-b-PDMA-b-PNIPAAM) that forms physically cross-linked hydrogels when transitioned from ambient to physiologic temperature and that incorporates mechanisms for reactive oxygen species (ROS) triggered degradation and drug release. At ambient temperature (25 °C), PPS-b-PDMA-b-PNIPAAM assembled into 66 ± 32 nm micelles comprising a hydrophobic PPS core and PNIPAAM on the outer corona. Upon heating to physiologic temperature (37 °C), which exceeds the lower critical solution temperature (LCST) of PNIPAAM, micelle solutions (at ≥2.5 wt %) sharply transitioned into stable, hydrated gels. Temperature-dependent rheology indicated that the equilibrium storage moduli (G') of hydrogels at 2.5, 5.0, and 7.5 wt % were 20, 380, and 850 Pa, respectively. The PPS-b-PDMA-b-PNIPAAM micelles were preloaded with the model drug Nile red, and the resulting hydrogels demonstrated ROS-dependent drug release. Likewise, exposure to the peroxynitrite generator SIN-1 degraded the mechanical properties of the hydrogels. The hydrogels were cytocompatible in vitro and were demonstrated to have utility for cell encapsulation and delivery. These hydrogels also possessed inherent cell-protective properties and reduced ROS-mediated cellular death in vitro. Subcutaneously injected PPS-b-PDMA-b-PNIPAAM polymer solutions formed stable hydrogels that sustained local release of the model drug Nile red for 14 days in vivo. These collective data demonstrate the potential use of PPS-b-PDMA-b-PNIPAAM as an injectable, cyto-protective hydrogel that overcomes conventional PNIPAAM hydrogel limitations such as syneresis, lack of degradability, and lack of inherent drug loading and environmentally responsive release mechanisms.

  12. In vitro studies of multiwalled carbon nanotube/ultrahigh molecular weight polyethylene nanocomposites with osteoblast-like MG63 cells

    Directory of Open Access Journals (Sweden)

    J. Reis

    2010-05-01

    Full Text Available Carbon nanotubes are highly versatile materials; new applications using them are continuously being developed. Special attention is being dedicated to the possible use of multiwalled carbon nanotubes in biomaterials contacting with bone. However, carbon nanotubes are also controversial in regards to effects exerted on living organisms. Carbon nanotubes can be used to improve the tribological properties of polymer/composite materials. Ultrahigh molecular weight polyethylene (UHMWPE is a polymer widely used in orthopedic applications that imply wear and particle generation. We describe here the response of human osteoblast-like MG63 cells after 6 days of culture in contact with artificially generated particles from both UHMWPE polymer and multiwalled carbon nanotubes (MWCNT/UHMWPE nanocomposites. This novel composite has superior wear behavior, having thus the potential to reduce the number of revision hip arthroplasty surgeries required by wear failure of acetabular cups and diminish particle-induced osteolysis. The results of an in vitro study of viability and proliferation and interleukin-6 (IL-6 production suggest good cytocompatibility, similar to that of conventional UHMWPE (WST-1 assay results are reported as percentage of control ± SD: UHMWPE = 96.19 ± 7.92, MWCNT/UHMWPE = 97.92 ± 8.29%; total protein: control = 139.73 ± 10.78, UHMWPE = 137.07 ± 6.17, MWCNT/UHMWPE = 163.29 ± 11.81 µg/mL; IL-6: control = 90.93 ± 10.30, UHMWPE = 92.52 ± 11.02, MWCNT/UHMWPE = 108.99 ± 9.90 pg/mL. Standard cell culture conditions were considered as control. These results, especially the absence of significant elevation in the osteolysis inductor IL-6 values, reinforce the potential of this superior wear-resistant composite for future orthopedic applications, when compared to traditional UHMWPE.

  13. Dendritic Cell

    OpenAIRE

    Sevda Söker

    2005-01-01

    Dendritic cells, a member of family of antigen presenting cells, are most effective cells in the primary immune response. Dendritic cells originated from dendron, in mean of tree in the Greek, because of their long and elaborate cytoplasmic branching processes. Dendritic cells constitute approximately 0.1 to 1 percent of the blood’s mononuclear cell. Dendritic cells are widely distributed, and specialized for antigen capture and T cell stimulation. In this article, structures and functions of...

  14. Interleukin-3 greatly expands non-adherent endothelial forming cells with pro-angiogenic properties

    Directory of Open Access Journals (Sweden)

    Lachlan M. Moldenhauer

    2015-05-01

    Full Text Available Circulating endothelial progenitor cells (EPCs provide revascularisation for cardiovascular disease and the expansion of these cells opens up the possibility of their use as a cell therapy. Herein we show that interleukin-3 (IL3 strongly expands a population of human non-adherent endothelial forming cells (EXnaEFCs with low immunogenicity as well as pro-angiogenic capabilities in vivo, making their therapeutic utilisation a realistic option. Non-adherent CD133+ EFCs isolated from human umbilical cord blood and cultured under different conditions were maximally expanded by day 12 in the presence of IL3 at which time a 350-fold increase in cell number was obtained. Cell surface marker phenotyping confirmed expression of the hematopoietic progenitor cell markers CD133, CD117 and CD34, vascular cell markers VEGFR2 and CD31, dim expression of CD45 and absence of myeloid markers CD14 and CD11b. Functional experiments revealed that EXnaEFCs exhibited classical properties of endothelial cells (ECs, namely binding of Ulex europaeus lectin, up-take of acetylated-low density lipoprotein and contribution to EC tube formation in vitro. These EXnaEFCs demonstrated a pro-angiogenic phenotype within two independent in vivo rodent models. Firstly, a Matrigel plug assay showed increased vascularisation in mice. Secondly, a rat model of acute myocardial infarction demonstrated reduced heart damage as determined by lower levels of serum creatinine and a modest increase in heart functionality. Taken together, these studies show IL3 as a potent growth factor for human CD133+ cell expansion with clear pro-angiogenic properties (in vitro and in vivo and thus may provide clinical utility for humans in the future.

  15. Study on cytocompatibility of poly(trimethylene carbonate) viaself-polymerization of dopamine and covalent immobilization of peptide%基于多巴胺自聚合及多肽固定的聚三亚甲基碳酸酯的细胞相容性评价

    Institute of Scientific and Technical Information of China (English)

    张江; 刘阳; 袁书恒; 温煦; 许芷菡; 杨晓婷; 王进; 黄楠

    2014-01-01

    针对聚三亚甲基碳酸酯(PTMC)内皮细胞相容性不足的特点,通过在其表面沉积聚多巴胺涂层并固定精氨酸-谷氨酸-天冬氨酸-缬氨酸(REDV)多肽改善PTMC的细胞相容性。水接触角测试表明 PT-MC表面沉积聚多巴胺及固定REDV后亲水性得到显著改善;原子力显微镜观察可以发现相比于PTMC,沉积聚多巴胺及固定REDV后的表面粗糙度明显增加;QCM-D 结果显示表面固定的 REDV 密度可达到98.4 ng/cm2,证明REDV可实现对 PTMC薄膜的固定修饰。体外内皮细胞和平滑肌细胞粘附与增殖评价表明REDV改性的PTMC 薄膜可促进内皮细胞的粘附与增殖,但对平滑肌细胞粘附增殖的促进作用并不显著。%In this study,due to the poor compatibility of poly (trimethylene carbonate)(PTMC)with endotheli-al cells (ECs),the polydopamine coating and further immobilization of the peptide REDV (Arg-Glu-Asp-Val) were used to promote adhesion and proliferation of ECs.The hydrophilicity of PTMC film modified by polydo-paminecoating and immobilization of the peptide REDV was significantly improved;compared to the surface of PTMC,the surfaces of P-D-48 h and P-D-REDV had higher average roughness.The result of QCM-D indicated that 98.4 ng/cm2 REDV was immobilized on the PTMC.Endothelial cells in vitro indicated that the PTMC film immobilized with REDV peptidescan promote the adhesion,spreading and proliferation of ECs,but this REDV-modified PTMC film had no significant influence on the adhesion and proliferation of smooth muscle cells.

  16. Cellular interactions of lauric acid and dextran-coated magnetite nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Pradhan, Pallab [School of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai 400076 (India); Giri, Jyotsnendu [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Mumbai 400076 (India); Banerjee, Rinti [School of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai 400076 (India); Bellare, Jayesh [School of Biosciences and Bioengineering, Indian Institute of Technology, Mumbai 400076 (India); Bahadur, Dhirendra [Department of Metallurgical Engineering and Materials Science, Indian Institute of Technology, Mumbai 400076 (India)]. E-mail: dhirenb@iitb.ac.in

    2007-04-15

    In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.

  17. Cellular interactions of lauric acid and dextran-coated magnetite nanoparticles

    Science.gov (United States)

    Pradhan, Pallab; Giri, Jyotsnendu; Banerjee, Rinti; Bellare, Jayesh; Bahadur, Dhirendra

    2007-04-01

    In vitro cytocompatibility and cellular interactions of lauric acid and dextran-coated magnetite nanoparticles were evaluated with two different cell lines (mouse fibroblast and human cervical carcinoma). Lauric acid-coated magnetite nanoparticles were less cytocompatible than dextran-coated magnetite nanoparticles and cellular uptake of lauric acid-coated magnetic nanoparticles was more than that of dextran-coated magnetite nanoparticles. Lesser cytocompatibility and higher uptake of lauric acid-coated magnetite nanoparticles as compared to dextran-coated magnetic nanoparticles may be due to different cellular interactions by coating material. Thus, coating plays an important role in modulation of biocompatibility and cellular interaction of magnetic nanoparticles.

  18. The effect of injectable gelatin-hydroxyphenylpropionic acid hydrogel matrices on the proliferation, migration, differentiation and oxidative stress resistance of adult neural stem cells.

    Science.gov (United States)

    Lim, Teck Chuan; Toh, Wei Seong; Wang, Li-Shan; Kurisawa, Motoichi; Spector, Myron

    2012-04-01

    Transplanted or endogenous neural stem cells often lack appropriate matrix in cavitary lesions in the central nervous system. In this study, gelatin-hydroxyphenylpropionic acid (Gtn-HPA), which could be enzymatically crosslinked with independent tuning of crosslinking degree and gelation rate, was explored as an injectable hydrogel for adult neural stem cells (aNSCs). The storage modulus of Gtn-HPA could be tuned (449-1717 Pa) to approximate adult brain tissue. Gtn-HPA was cytocompatible with aNSCs (yielding high viability >93%) and promoted aNSC adhesion. Gtn-HPA demonstrated a crosslinking-based approach for preconditioning aNSCs and increased the resistance of aNSCs to oxidative stress, improving their viability from 8-15% to 84% when challenged with 500 μM H(2)O(2). In addition, Gtn-HPA was able to modulate proliferation and migration of aNSCs in relation to the crosslinking degree. Finally, Gtn-HPA exhibited bias for neuronal cells. In mixed differentiation conditions, Gtn-HPA increased the proportion of aNSCs expressing neuronal marker β-tubulin III to a greater extent than that for astrocytic marker glial fibrillary acidic protein, indicating an enhancement in differentiation towards neuronal lineage. Between neuronal and astrocytic differentiation conditions, Gtn-HPA also selected for higher survival in the former. Overall, Gtn-HPA hydrogels are promising injectable matrices for supporting and influencing aNSCs in ways that may be beneficial for brain tissue regeneration after injuries.

  19. Molecular Mechanisms of Microcystin Toxicity in Animal Cells

    Directory of Open Access Journals (Sweden)

    Alexandre Campos

    2010-01-01

    Full Text Available Microcystins (MC are potent hepatotoxins produced by the cyanobacteria of the genera Planktothrix, Microcystis, Aphanizomenon, Nostoc and Anabaena. These cyclic heptapeptides have strong affinity to serine/threonine protein phosphatases (PPs thereby acting as an inhibitor of this group of enzymes. Through this interaction a cascade of events responsible for the MC cytotoxic and genotoxic effects in animal cells may take place. Moreover MC induces oxidative stress in animal cells and together with the inhibition of PPs, this pathway is considered to be one of the main mechanisms of MC toxicity. In recent years new insights on the key enzymes involved in the signal-transduction and toxicity have been reported demonstrating the complexity of the interaction of these toxins with animal cells. Key proteins involved in MC up-take, biotransformation and excretion have been identified, demonstrating the ability of aquatic animals to metabolize and excrete the toxin. MC have shown to interact with the mitochondria. The consequences are the dysfunction of the organelle, induction of reactive oxygen species (ROS and cell apoptosis. MC activity leads to the differential expression/activity of transcriptional factors and protein kinases involved in the pathways of cellular differentiation, proliferation and tumor promotion activity. This activity may result from the direct inhibition of the protein phosphatases PP1 and PP2A. This review aims to summarize the increasing data regarding the molecular mechanisms of MC toxicity in animal systems, reporting for direct MC interacting proteins and key enzymes in the process of toxicity biotransformation/excretion of these cyclic peptides.

  20. Hierarchical micro/nanostructured titanium with balanced actions to bacterial and mammalian cells for dental implants

    Directory of Open Access Journals (Sweden)

    Zhu Y

    2015-10-01

    Full Text Available Yu Zhu,1,* Huiliang Cao,2,* Shichong Qiao,1,* Manle Wang,2,3 Yingxin Gu,1 Huiwen Luo,1 Fanhao Meng,2 Xuanyong Liu,2 Hongchang Lai1 1Department of Oral and Maxillofacial Implantology, Shanghai Key Laboratory of Stomatology, Shanghai Ninth People’s Hospital, School of Medicine, Shanghai Jiao Tong University, 2State Key Laboratory of High Performance Ceramics and Superfine Microstructure, Shanghai Institute of Ceramics, Chinese Academy of Sciences, 3School of Materials Engineering, Shanghai University of Engineering Science, Shanghai, People’s Republic of China *These authors contributed equally to this work Abstract: A versatile strategy to endow dental implants with long-term antibacterial ability without compromising the cytocompatibility is highly desirable to combat implant-related infection. Silver nanoparticles (Ag NPs have been utilized as a highly effective and broad-spectrum antibacterial agent for surface modification of biomedical devices. However, the high mobility and subsequent hazardous effects of the particles on mammalian cells may limit its practical applications. Thus, Ag NPs were immobilized on the surface of sand-blasted, large grit, and acid-etched (SLA titanium by manipulating the atomic-scale heating effect of silver plasma immersion ion implantation. The silver plasma immersion ion implantation-treated SLA surface gave rise to both good antibacterial activity and excellent compatibility with mammalian cells. The antibacterial activity rendered by the immobilized Ag NPs was assessed using Fusobacterium nucleatum and Staphylococcus aureus, commonly suspected pathogens for peri-implant disease. The immobilized Ag NPs offered a good defense against multiple cycles of bacteria attack in both F. nucleatum and S. aureus, and the mechanism was independent of silver release. F. nucleatum showed a higher susceptibility to Ag NPs than S. aureus, which might be explained by the presence of different wall structures. Moreover, the

  1. Galvanic Cells

    Science.gov (United States)

    Young, I. G.

    1973-01-01

    Many standard physical chemistry textbooks contain ambiguities which lead to confusion about standard electrode potentials, calculating cell voltages, and writing reactions for galvanic cells. This article shows how standard electrode potentials can be used to calculate cell voltages and deduce cell reactions. (Author/RH)

  2. Cell Biochips

    Science.gov (United States)

    Pioufle, B. Le; Picollet-D'Hahan, N.

    A cell biochip is a microsystem, equipped with electronic and microfluidic functions, designed to manipulate or analyse living cells. The first publications in this emerging area of research appeared toward the end of the 1980s. In 1989 Washizu described a biochip designed to fuse two cells by electropermeabilisation of the cytoplasmic membrane [1]. Research centers have devised a whole range of cell chip structures, for simultaneous or sequential analysis of single cells, cell groups, or cell tissues reconstituted on the chip. The cells are arranged in a square array on a parallel cell chip for parallel analysis, while they are examined and processed one by one in a microchannel in the case of a series cell chip. In contrast to these biochips for high-throughput analysis of a large number of cells, single-cell chips focus on the analysis of a single isolated cell. As in DNA microarrays, where a large number of oligonucleotides are ordered in a matrix array, parallel cell chips order living cells in a similar way. At each point of the array, the cells can be isolated, provided that the cell type allows this, e.g., blood cells, or cultivated in groups (most adhesion cells can only survive in groups). The aim is to allow massively parallel analysis or processing. Le Pioufle et al. describe a microdevice for the culture of single cells or small groups of cells in a micropit array [2]. Each pit is equipped to stimulate the cell or group of cells either electrically or fluidically. Among the applications envisaged are gene transfer, cell sorting, and screening in pharmacology. A complementary approach, combining the DNA microarray and cell biochip ideas, has been put forward by Bailey et al. [3]. Genes previously arrayed on the chip transfect the cultured cells on the substrate depending on their position in the array (see Fig. 19.1). This way of achieving differential lipofection on a chip was then taken up again by Yoshikawa et al. [4] with primary cells, more

  3. An in vitro mechanism study on the proliferation and pluripotency of human embryonic stems cells in response to magnesium degradation.

    Directory of Open Access Journals (Sweden)

    Thanh Yen Nguyen

    Full Text Available Magnesium (Mg is a promising biodegradable metallic material for applications in cellular/tissue engineering and biomedical implants/devices. To advance clinical translation of Mg-based biomaterials, we investigated the effects and mechanisms of Mg degradation on the proliferation and pluripotency of human embryonic stem cells (hESCs. We used hESCs as the in vitro model system to study cellular responses to Mg degradation because they are sensitive to toxicants and capable of differentiating into any cell types of interest for regenerative medicine. In a previous study when hESCs were cultured in vitro with either polished metallic Mg (99.9% purity or pre-degraded Mg, cell death was observed within the first 30 hours of culture. Excess Mg ions and hydroxide ions induced by Mg degradation may have been the causes for the observed cell death; hence, their respective effects on hESCs were investigated for the first time to reveal the potential mechanisms. For this purpose, the mTeSR®1 hESC culture media was either modified to an alkaline pH of 8.1 or supplemented with 0.4-40 mM of Mg ions. We showed that the initial increase of media pH to 8.1 had no adverse effect on hESC proliferation. At all tested Mg ion dosages, the hESCs grew to confluency and retained pluripotency as indicated by the expression of OCT4, SSEA3, and SOX2. When the supplemental Mg ion dosages increased to greater than 10 mM, however, hESC colony morphology changed and cell counts decreased. These results suggest that Mg-based implants or scaffolds are promising in combination with hESCs for regenerative medicine applications, providing their degradation rate is moderate. Additionally, the hESC culture system could serve as a standard model for cytocompatibility studies of Mg in vitro, and an identified 10 mM critical dosage of Mg ions could serve as a design guideline for safe degradation of Mg-based implants/scaffolds.

  4. Higher prevalence of sexual transmitted diseases and correlates of genital warts among heterosexual males attending sexually transmitted infection clinics (MSCs in Jiangmen, China: implication for the up-taking of STD related service.

    Directory of Open Access Journals (Sweden)

    Shujie Huang

    Full Text Available Increasing burden of STDs is one of China's major public health concerns. However, only a limited number of studies have ever investigated the prevalence of these STDs, particular for genital warts and its correlates among heterosexual males attending STD clinics in China. In order to fill this gap, we conducted a cross-sectional study among MSCs in Jiangmen, China, between the years of 2009 and 2010.The eligible participants were recruited from several STD-clinics in public hospitals. We collected demographic information and behaviors of the participants. After HIV and syphilis testing, we further checked whether the participants had genital warts and genital herpes. In addition, urine samples were collected from part of the participants for CT and NG testing.Of the 533 eligible participants, over three-fifths were aged 35 or below, nearly three quarters had no college degree, over three-fifths were residence of Jiangmen. The prevalence of HIV, syphilis, genital warts, genital herpes, CT and NG were 0.19%, 7.50%, 7.32%, 5.25%, 9.73% and 6.19%, respectively. Living with family members (versus living alone, no STD-related service in past year, experiencing STDs related symptoms in past year, and sex with FSWs in last three months were positively associated with genital warts, with adjusted ORs of 5.54 (95% CI 1.94-15.81, 2.26 (95% CI 1.08-4.74, 1.99 (95% CI 1.00-3.99 and 2.01 (95% CI 1.00-4.04, respectively.Our study indicates that the prevalence of STDs among MSCs in Jiangmen was high, which may further spread HIV among MSCs. Targeted interventions that focused on STDs related services uptake should be implemented urgently.

  5. Higher Prevalence of Sexual Transmitted Diseases and Correlates of Genital Warts among Heterosexual Males Attending Sexually Transmitted Infection Clinics (MSCs) in Jiangmen, China: Implication for the Up-Taking of STD Related Service

    Science.gov (United States)

    Zhu, Zhengjun; Lu, Hekun; Tan, Xueling; Zhang, Baoyuan; Best, John; Yang, Ligang; Zheng, Heping; Jiang, Ning; Yin, Yueping; Yang, Bin; Chen, Xiangsheng

    2015-01-01

    Background Increasing burden of STDs is one of China’s major public health concerns. However, only a limited number of studies have ever investigated the prevalence of these STDs, particular for genital warts and its correlates among heterosexual males attending STD clinics in China. In order to fill this gap, we conducted a cross-sectional study among MSCs in Jiangmen, China, between the years of 2009 and 2010. Method The eligible participants were recruited from several STD-clinics in public hospitals. We collected demographic information and behaviors of the participants. After HIV and syphilis testing, we further checked whether the participants had genital warts and genital herpes. In addition, urine samples were collected from part of the participants for CT and NG testing. Results Of the 533 eligible participants, over three-fifths were aged 35 or below, nearly three quarters had no college degree, over three-fifths were residence of Jiangmen. The prevalence of HIV, syphilis, genital warts, genital herpes, CT and NG were 0.19%, 7.50%, 7.32%, 5.25%, 9.73% and 6.19%, respectively. Living with family members (versus living alone), no STD-related service in past year, experiencing STDs related symptoms in past year, and sex with FSWs in last three months were positively associated with genital warts, with adjusted ORs of 5.54 (95% CI 1.94–15.81), 2.26 (95% CI 1.08–4.74), 1.99 (95% CI 1.00–3.99) and 2.01 (95% CI 1.00–4.04), respectively. Conclusion Our study indicates that the prevalence of STDs among MSCs in Jiangmen was high, which may further spread HIV among MSCs. Targeted interventions that focused on STDs related services uptake should be implemented urgently. PMID:25811185

  6. Stem cells in cell transplantation.

    Science.gov (United States)

    Sanmartin, Agneta; English, Denis; Sanberg, Paul R

    2006-12-01

    This commentary documents the increased number of stem cell-related research reports recently published in the cell transplantation field in the journal Cell Transplantation. The journal covers a wide range of issues in cell-based therapy and regenerative medicine and is attracting clinical and preclinical articles from around the world. It thereby complements and extends the basic coverage of stem cell physiology reported in Stem Cells and Development. Sections in Cell Transplantation cover neuroscience, diabetes, hepatocytes, bone, muscle, cartilage, skin, vessels, and other tissues, as well as tissue engineering that employs novel methods with stem cells. Clearly, the continued use of biomedical engineering will depend heavily on stem cells, and these two journals are well positioned to provide comprehensive coverage of these developments.

  7. Engineering cell-cell signaling.

    Science.gov (United States)

    Blagovic, Katarina; Gong, Emily S; Milano, Daniel F; Natividad, Robert J; Asthagiri, Anand R

    2013-10-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling on the basis of quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilize synthetic cells, advanced 'chassis' and predictive modeling to engineer the form and function of living tissues.

  8. Glucose-induced Ca2 + signals in rat pancreatic β cells

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Using microfluorometry to assay intracellular Ca2+ , the influences of varied factors on glucose induced Ca22+ signals, such as glucose-induced initial decline phase (GIDP), Ca2+ oscillation, and Ca2+ release from internal stores, were investigated in single rat pancreatic β cells. Glucose was able to evoke GIDP even at non-stimulus concentration (5 mol/L), which is insufficient to induce Ca2+ spikes. GIDP was dependent on neither membrane depo larization nor extraeellular Ca2+ . However, GIDP was inhibited by thapsigargin, indicating a dependence on Ca2+ up take by Ca22+ stores. The glucose-induced calcium oscillation was inhibited when external Ca2+ was removed. However, thapsigargin could not block the Ca2+ oscillation. These results suggest that maintenance of Ca22+ oscillation requires ex tracellular Ca2+ but not Ca2+ stores. Glucose was able to evoke Ca2+ signals even in the absence of external Ca2+ . The glucose-induced Ca2+ release from intracellular Ca2+ stores was blocked by TTX. However, TTX had no effect on high K--induced Ca2+ store release, suggesting that membrane depolarization can directly release Ca2+ from some internal Ca2+ stores in β cells.

  9. Synthesis, characterization, and in-vitro cytocompatibility of amorphous β-tri-calcium magnesium phosphate ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Satish S., E-mail: sss42@pitt.edu [Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Roy, Abhijit, E-mail: abr20@pitt.edu [Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Lee, Boeun, E-mail: bol11@pitt.edu [Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Banerjee, Ipsita [Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Kumta, Prashant N., E-mail: pkumta@pitt.edu [Department of Chemical & Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Center for Craniofacial Regeneration, University of Pittsburgh, Pittsburgh, PA 15261 (United States); Department of Mechanical Engineering and Materials Science, University of Pittsburgh, PA 15261 (United States)

    2016-10-01

    Biphasic mixtures of crystalline β-tricalcium magnesium phosphate (β-TCMP) and an amorphous calcium magnesium phosphate have been synthesized and reported to support enhanced hMSC differentiation in comparison to β-tricalcium phosphate (β-TCP) due to the release of increased amounts of bioactive ions. In the current study, completely amorphous β-TCMP has been synthesized which is capable of releasing increased amounts of Mg{sup 2+} and PO{sub 4}{sup 3−} ions, rather than a biphasic mixture as earlier reported. The amorphous phase formed was observed to crystallize between temperatures of 400–600 °C. The scaffolds prepared with amorphous β-TCMP were capable of supporting enhanced hMSC proliferation and differentiation in comparison to commercially available β-TCP. However, a similar gene expression of mature osteoblast markers, OCN and COL-1, in comparison to biphasic β-TCMP was observed. To further study the role of Mg{sup 2+} and PO{sub 4}{sup 3−} ions in regulating hMSC osteogenic differentiation, the capability of hMSCs to mineralize in growth media supplemented with Mg{sup 2+} and PO{sub 4}{sup 3−} ions was studied. Interestingly, 5 mM PO{sub 4}{sup 3−} supported mineralization while the addition of 5 mM Mg{sup 2+} to 5 mM PO{sub 4}{sup 3−} inhibited mineralization. It was therefore concluded that the release of Ca{sup 2+} ions from β-TCMP scaffolds also plays a role in regulating osteogenic differentiation on these scaffolds and it is noted that further work is required to more accurately determine the exact role of Mg{sup 2+} in regulating hMSC osteogenic differentiation. - Highlights: • Synthesis of amorphous Mg containing beta tricalcium phosphate ceramics • Amorphous beta TCMP supports enhanced hMSC proliferation and differentiation. • Amorphous beta TCMP shows comparable OCN and COL-1 expression to biphasic TCMP. • Presence of 5 mM Mg{sup 2+} and PO{sub 4}{sup 3−} ions in growth media inhibits hMSC mineralization.

  10. Antimicrobial activity and cytocompatibility of silver nanoparticles coated catheters via a biomimetic surface functionalization strategy

    OpenAIRE

    Deng, Jiexi; Wu, Ke; Yang, Yun; Zhang, Yanmei; Lin,Changjian

    2015-01-01

    Ke Wu,1 Yun Yang,2,3 Yanmei Zhang,2,3 Jiexi Deng,1 Changjian Lin2,31Department of Cardiology, The Affiliated Dongnan Hospital of Xiamen University, Zhangzhou, 2Department of Medical Materials, Beijing Medical Implant Engineering Research Center, Beijing Naton Technology Group, Beijing, 3State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, People’s Republic of ChinaAbstract: Ca...

  11. Antimicrobial activity and cytocompatibility of silver nanoparticles coated catheters via a biomimetic surface functionalization strategy

    OpenAIRE

    Wu K; Yang Y.; YM, Zhang; Deng JX; Lin CJ

    2015-01-01

    Ke Wu,1 Yun Yang,2,3 Yanmei Zhang,2,3 Jiexi Deng,1 Changjian Lin2,31Department of Cardiology, The Affiliated Dongnan Hospital of Xiamen University, Zhangzhou, 2Department of Medical Materials, Beijing Medical Implant Engineering Research Center, Beijing Naton Technology Group, Beijing, 3State Key Laboratory of Physical Chemistry of Solid Surfaces, Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, People’s Republic of ChinaAbstract: Cathet...

  12. Cytocompatibility of aliphatic polyesters - in vitro study on fibroblasts and macrophages

    NARCIS (Netherlands)

    Pamula, E.; Dobrzynski, P.; Szot, B.; Kretek, M.; Krawciow, M.; Plytycz, B.; Chadzinska, M.K.

    2008-01-01

    A resorbable copolymer of glycolide and L-lactide (PGLA), a terpolymer of glycolide, L-lactide, and epsilon-caprolactone (PGLCL), and a copolymer of glycolide and E-caprolactone (PGCL) were synthesized by ring opening polymerization Using Zirconium acetylacetonate (Zr(acac)(4)) as an initiator. The

  13. A study of cytocompatibility and degradation of iron-based biodegradable materials.

    Science.gov (United States)

    Oriňaková, Renáta; Oriňak, Andrej; Giretová, Mária; Medvecký, L'ubomír; Kupková, Miriam; Hrubovčáková, Monika; Maskal'ová, Iveta; Macko, Ján; Kal'avský, František

    2016-02-01

    Biodegradable metallic implants are of significant importance in the replacement of bones or the repair of bone defects. Iron-phosphate-coated carbonyl iron powder (Fe/P) was prepared by the phosphating method. Moreover, Fe/P-Mn alloy was produced by sintering the Fe/P powder mixed with manganese powder. Bare carbonyl iron samples and the Fe/P and Fe/P-Mn sintered samples were evaluated for their microstructure, cytotoxicity, and hemocompatibility. The microstructure of the sintered samples was examined using an optical microscope and scanning electron microscopic analysis. Corrosion behavior was evaluated by potentiodynamic polarization in Hank's solution. The in vitro biocompatibilities were investigated by cytotoxicity and hemolysis tests. The results obtained demonstrate that the addition of Mn resulted in higher surface inhomogeneity, porosity and roughness as well as in increased cytotoxicity. The phosphate coating has a moderately negative effect on the cytotoxicity. The corrosion rates determined from Tafel diagrams were ordered in the following sequence: Fe/P-Mn, Fe, Fe/P from high to low. The hemocompatibility of experimental samples was ordered in the following sequence: Fe/P, Fe/P-Mn, Fe from high to low. All samples were found to be hemocompatible.

  14. Preparation, physical-chemical characterization, and cytocompatibility of polymeric calcium phosphate cements.

    Science.gov (United States)

    Khashaba, Rania M; Moussa, Mervet; Koch, Christopher; Jurgensen, Arthur R; Missimer, David M; Rutherford, Ronny L; Chutkan, Norman B; Borke, James L

    2011-01-01

    Aim. Physicochemical mechanical and in vitro biological properties of novel formulations of polymeric calcium phosphate cements (CPCs) were investigated. Methods. Monocalcium phosphate, calcium oxide, and synthetic hydroxyapatite were combined with either modified polyacrylic acid, light activated polyalkenoic acid, or polymethyl vinyl ether maleic acid to obtain Types I, II, and III CPCs. Setting time, compressive and diametral strength of CPCs was compared with zinc polycarboxylate cement (control). Specimens were characterized using X-ray diffraction, scanning electron microscopy, and infrared spectroscopy. In vitro cytotoxicity of CPCs and control was assessed. Results. X-ray diffraction analysis showed hydroxyapatite, monetite, and brushite. Acid-base reaction was confirmed by the appearance of stretching peaks in IR spectra of set cements. SEM revealed rod-like crystals and platy crystals. Setting time of cements was 5-12 min. Type III showed significantly higher strength values compared to control. Type III yielded high biocompatibility. Conclusions. Type III CPCs show promise for dental applications.

  15. Preparation, Physical-Chemical Characterization, and Cytocompatibility of Polymeric Calcium Phosphate Cements

    Science.gov (United States)

    Khashaba, Rania M.; Moussa, Mervet; Koch, Christopher; Jurgensen, Arthur R.; Missimer, David M.; Rutherford, Ronny L.; Chutkan, Norman B.; Borke, James L.

    2011-01-01

    Aim. Physicochemical mechanical and in vitro biological properties of novel formulations of polymeric calcium phosphate cements (CPCs) were investigated. Methods. Monocalcium phosphate, calcium oxide, and synthetic hydroxyapatite were combined with either modified polyacrylic acid, light activated polyalkenoic acid, or polymethyl vinyl ether maleic acid to obtain Types I, II, and III CPCs. Setting time, compressive and diametral strength of CPCs was compared with zinc polycarboxylate cement (control). Specimens were characterized using X-ray diffraction, scanning electron microscopy, and infrared spectroscopy. In vitro cytotoxicity of CPCs and control was assessed. Results. X-ray diffraction analysis showed hydroxyapatite, monetite, and brushite. Acid-base reaction was confirmed by the appearance of stretching peaks in IR spectra of set cements. SEM revealed rod-like crystals and platy crystals. Setting time of cements was 5–12 min. Type III showed significantly higher strength values compared to control. Type III yielded high biocompatibility. Conclusions. Type III CPCs show promise for dental applications. PMID:21941551

  16. Preparation, Physical-Chemical Characterization, and Cytocompatibility of Polymeric Calcium Phosphate Cements

    Directory of Open Access Journals (Sweden)

    Rania M. Khashaba

    2011-01-01

    Full Text Available Aim. Physicochemical mechanical and in vitro biological properties of novel formulations of polymeric calcium phosphate cements (CPCs were investigated. Methods. Monocalcium phosphate, calcium oxide, and synthetic hydroxyapatite were combined with either modified polyacrylic acid, light activated polyalkenoic acid, or polymethyl vinyl ether maleic acid to obtain Types I, II, and III CPCs. Setting time, compressive and diametral strength of CPCs was compared with zinc polycarboxylate cement (control. Specimens were characterized using X-ray diffraction, scanning electron microscopy, and infrared spectroscopy. In vitro cytotoxicity of CPCs and control was assessed. Results. X-ray diffraction analysis showed hydroxyapatite, monetite, and brushite. Acid-base reaction was confirmed by the appearance of stretching peaks in IR spectra of set cements. SEM revealed rod-like crystals and platy crystals. Setting time of cements was 5–12 min. Type III showed significantly higher strength values compared to control. Type III yielded high biocompatibility. Conclusions. Type III CPCs show promise for dental applications.

  17. Cell Motility

    CERN Document Server

    Lenz, Peter

    2008-01-01

    Cell motility is a fascinating example of cell behavior which is fundamentally important to a number of biological and pathological processes. It is based on a complex self-organized mechano-chemical machine consisting of cytoskeletal filaments and molecular motors. In general, the cytoskeleton is responsible for the movement of the entire cell and for movements within the cell. The main challenge in the field of cell motility is to develop a complete physical description on how and why cells move. For this purpose new ways of modeling the properties of biological cells have to be found. This long term goal can only be achieved if new experimental techniques are developed to extract physical information from these living systems and if theoretical models are found which bridge the gap between molecular and mesoscopic length scales. Cell Motility gives an authoritative overview of the fundamental biological facts, theoretical models, and current experimental developments in this fascinating area.

  18. Photovoltaic Cells

    Directory of Open Access Journals (Sweden)

    Karolis Kiela

    2012-04-01

    Full Text Available The article deals with an overview of photovoltaic cells that are currently manufactured and those being developed, including one or several p-n junction, organic and dye-sensitized cells using quantum dots. The paper describes the advantages and disadvantages of various photovoltaic cells, identifies the main parameters, explains the main reasons for the losses that may occur in photovoltaic cells and looks at the ways to minimize them.Article in Lithuanian

  19. The pan-DAC inhibitor LBH589 is a multi-functional agent in breast cancer cells: cytotoxic drug and inducer of sodium-iodide symporter (NIS).

    Science.gov (United States)

    Fortunati, N; Catalano, M G; Marano, F; Mugoni, V; Pugliese, M; Bosco, O; Mainini, F; Boccuzzi, G

    2010-12-01

    New drugs with anti-tumor activity, also able to modify the expression of selected molecules, are under evaluation in breast cancer which is becoming resistant to conventional treatment, or in metastatic disease. The sodium-iodide symporter (NIS), which mediates iodide uptake into thyroid cells, and is the molecular basis of radioiodine imaging and therapy in thyroid cancer, is also expressed in a large portion of breast tumors. Since NIS expression in breast cancer is not sufficient for a significant iodide uptake, drugs able to induce its expression and correct function are under evaluation. In the present study, we report for the first time that the pan-deacetylase (DAC) inhibitor LBH589 (panobinostat) significantly induced NIS, both as mRNA and as protein, through the increase of NIS promoter activity, with the final consequence of obtaining a significant up-take of iodide in MCF7, T47D, and MDA-MB231 breast cancer cells. Moreover, we observed that LBH589 causes a significant reduction in cell viability of estrogen-sensitive and -insensitive breast cancer cells within nanomolar range. The anti-tumor effect of LBH589 is sustained by apoptosis induction and cell cycle arrest in G(2)/M. In conclusion, our data suggest that LBH589 might be a powerful tool in the management of breast cancer due to its multiple effects and support a potential application of LBH589 in the diagnosis and treatment of this disease.

  20. Novel 3D scaffold with enhanced physical and cell response properties for bone tissue regeneration, fabricated by patterned electrospinning/electrospraying.

    Science.gov (United States)

    Hejazi, Fatemeh; Mirzadeh, Hamid

    2016-09-01

    Developing three dimensional scaffolds mimicking the nanoscale structure of native extracellular matrix is a key parameter in tissue regeneration. In this study, we aimed to introduce a novel 3D structures composed of nanofibers (NF) and micro particles (MP) and compare their efficiency with 2D nanofibrous scaffold. The conventional nanofibrous PCL scaffolds are 2D mats fabricated by the electrospinning technique, whereas the NF/MP and patterned NF/MP PCL scaffolds are three dimensional structures fabricated by a modified electrospinning/electrospraying technique. The mentioned method was carried out by varying the electrospinning solution parameters and use of a metal mesh as the collector. Detailed fabrication process and morphological properties of the fabricated structures is discussed and porosity, pore size and PBS solution absorption value of the prepared structures are reported. Compared with the 2D structure, 3D scaffolds possessed enhanced porosity and pore size which led to the significant increase in their water uptake capacity. In vitro cell experiments were carried out on the prepared structures by the use of MG-63 osteosarcoma cell line. The fabricated 3D structures offered significantly increased cell attachment, spread and diffusion which were confirmed by SEM analysis. In vitro cytocompatibility assessed by MTT colorimetric assay indicated a continuous cell proliferation over 21 days on the innovative 3D structure, while on 2D mat cell proliferation stopped at early time points. Enhanced osteogenic differentiation of the seeded MG-63 cells on 3D scaffold was confirmed by the remarkable ALP activity together with increased and accelerated calcium deposition on this structure compared to 2D mat. Massive and well distributed bone minerals formed on patterned 3D structure were shown by EDX analysis. In comparison between NF/MP quasi-3D and Patterned NF/MP 3D scaffolds, patterned structures proceeded in all of the above properties. As such, the

  1. Engineering Cell-Cell Signaling

    OpenAIRE

    Blagovic, Katarina; Gong, Emily S.; Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R

    2013-01-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cel...

  2. Anion-Channel Blockers Inhibit S-Type Anion Channels and Abscisic Acid Responses in Guard Cells.

    Science.gov (United States)

    Schwartz, A.; Ilan, N.; Schwarz, M.; Scheaffer, J.; Assmann, S. M.; Schroeder, J. I.

    1995-10-01

    The effects of anion-channel blockers on light-mediated stomatal opening, on the potassium dependence of stomatal opening, on stomatal responses to abscisic acid (ABA), and on current through slow anion channels in the plasma membrane of guard cells were investigated. The anion-channel blockers anthracene-9-carboxylic acid (9-AC) and niflumic acid blocked current through slow anion channels of Vicia faba L. guard cells. Both 9-AC and niflumic acid reversed ABA inhibition of stomatal opening in V. faba L. and Commelina communis L. The anion-channel blocker probenecid also abolished ABA inhibition of stomatal opening in both species. Additional tests of 9-AC effects on stomatal aperture in Commelina revealed that application of this anion-channel blocker allowed wide stomatal opening under low (1 mM) KCI conditions and increased the rate of stomatal opening under both low and high (100 mM) KCI conditions. These results indicate that anion channels can function as a negative regulator of stomatal opening, presumably by allowing anion efflux and depolarization, which prohibits ion up-take in guard cells. Furthermore, 9-AC prevented ABA induction of stomatal closure. A model in which ABA activation of anion channels contributes a rate-limiting mechanism during ABA-induced stomatal closure and inhibition of stomatal opening is discussed.

  3. Stem Cells

    Directory of Open Access Journals (Sweden)

    Madhukar Thakur

    2015-02-01

    Full Text Available Objective: The objective of this presentation is to create awareness of stem cell applications in the ISORBE community and to foster a strategy of how the ISORBE community can disseminate information and promote the use of radiolabeled stem cells in biomedical applications. Methods: The continued excitement in Stem Cells, in many branches of basic and applied biomedical science, stems from the remarkable ability of stem cells to divide and develop into different types of cells in the body. Often called as Magic Seeds, stem cells are produced in bone marrow and circulate in blood, albeit at a relatively low concentration. These virtues together with the ability of stem cells to grow in tissue culture have paved the way for their applications to generate new and healthy tissues and to replace diseased or injured human organs. Although possibilities of stem cell applications are many, much remains yet to be understood of these remarkable magic seeds. Conclusion: This presentation shall briefly cover the origin of stem cells, the pros and cons of their growth and division, their potential application, and shall outline some examples of the contributions of radiolabeled stem cells, in this rapidly growing branch of biomedical science

  4. Types of Stem Cells

    Science.gov (United States)

    ... Stem Cell Glossary Search Toggle Nav Types of Stem Cells Stem cells are the foundation from which all ... Learn About Stem Cells > Types of Stem Cells Stem cells Stem cells are the foundation for every organ ...

  5. Water-soluble nanoconjugates of quantum dot-chitosan-antibody for in vitro detection of cancer cells based on “enzyme-free” fluoroimmunoassay

    Energy Technology Data Exchange (ETDEWEB)

    Mansur, Herman S., E-mail: hmansur@demet.ufmg.br [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Mansur, Alexandra A.P. [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Soriano-Araújo, Amanda [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Department of Preventive Veterinary Medicine, Veterinary School, UFMG (Brazil); Lobato, Zélia I.P. [Department of Preventive Veterinary Medicine, Veterinary School, UFMG (Brazil); Carvalho, Sandhra M. de [Center of Nanoscience, Nanotechnology, and Innovation-CeNano" 2I, Department of Metallurgical and Materials Engineering, Federal University of Minas Gerais, UFMG, Av. Presidente Antônio Carlos, 6627, Belo Horizonte, MG 31.270-901 (Brazil); Department of Physiology and Biophysics, ICB, UFMG (Brazil); Leite, Maria de Fatima [Department of Physiology and Biophysics, ICB, UFMG (Brazil)

    2015-07-01

    chitosan-antibody immunoconjugate ligands. • Water-soluble CdS QDs/chitosan conjugates were prepared via one-step route. • Fluorescent nanoconjugates were effective for in vitro detection of cancer antigen. • “Enzyme-free” QD-Fluoroimmunoassay was developed for detection of cancer antigen. • Cytocompatibility of CdS-QDs/immunoconjugates was evaluated by cell viability assays.

  6. Fuel Cells

    DEFF Research Database (Denmark)

    Smith, Anders; Pedersen, Allan Schrøder

    2014-01-01

    Fuel cells have been the subject of intense research and development efforts for the past decades. Even so, the technology has not had its commercial breakthrough yet. This entry gives an overview of the technological challenges and status of fuel cells and discusses the most promising applications...... of the different types of fuel cells. Finally, their role in a future energy supply with a large share of fluctuating sustainable power sources, e.g., solar or wind, is surveyed....

  7. Stem cells.

    Science.gov (United States)

    Redi, Carlo Alberto; Monti, Manuela; Merico, Valeria; Neri, Tui; Zanoni, Mario; Zuccotti, Maurizio; Garagna, Silvia

    2007-01-01

    The application of stem cells to regenerative medicine is one of the actual hot topics in biomedicine. This research could help the cure of a number of diseases that are affecting a large share of the population. Some good results in cell replacement have already been obtained (infarcted heart, diabetes, Parkinson disease), apart from those of more traditional applications like severe burns and blood tumors. We are now facing crucial questions in stem cell biology. One of the key questions is how a cell begins to proliferate or differentiate. Genome reprogramming, both following nuclear transfer and cytoplast action, will likely highlight some of the molecular mechanisms of cell differentiation and dedifferentiation. In turn, these clues should be useful to the production of populations of reprogrammed cells that could develop into tissues or, in the future, into proper organs. We will overview what stem cells are, what roles they play in normal developmental processes and how stem cells could have the potential to treat diseases.

  8. Fuel Cells

    Science.gov (United States)

    Hawkins, M. D.

    1973-01-01

    Discusses the theories, construction, operation, types, and advantages of fuel cells developed by the American space programs. Indicates that the cell is an ideal small-scale power source characterized by its compactness, high efficiency, reliability, and freedom from polluting fumes. (CC)

  9. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    '. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...... and tantalizing than stem cells, in research, in medicine, or as products....

  10. Sickle cell anemia

    Science.gov (United States)

    ... Anemia - sickle cell; Hemoglobin SS disease (Hb SS); Sickle cell disease Images Red blood cells, sickle cell Red blood cells, normal Red blood ... multiple sickle cells Red blood cells, sickle cells Red blood cells, sickle and ... Heeney MM, Ware RE. Sickle cell disease. In: Orkin SH, Fisher DE, Ginsburg D, Look ...

  11. Bi-Cell Unit for Fuel Cell.

    Science.gov (United States)

    The patent concerns a bi-cell unit for a fuel cell . The bi-cell unit is comprised of two electrode packs. Each of the electrode packs includes an...invention relates in general to a bi-cell unit for a fuel cell and in particular, to a bi-cell unit for a hydrazine-air fuel cell .

  12. Cell, cell, cell: fuel cell applications moving ahead

    Energy Technology Data Exchange (ETDEWEB)

    Ross, E.

    2001-11-01

    Developments in fuel cell technology within the last decade, such as the targeting by major automakers of non-polluting fuel cells as an alternative to the internal combustion engine, are reviewed. For example, Ballard Power Systems of Vancouver is the exclusive supplier to both DaimlerCrysler and the Ford Motor Company of the fuel cell stacks that produce the power in fuel cell systems. Ballard plans the commercial launch of transit bus engines in 2002 and automotive products between 2003 and 2005. The company also sees huge opportunities for fuel cells in stationary and portable power applications. At the same time, the Calgary-based fuel cell division of Energy Ventures Inc. is developing a direct methanol fuel cell that eliminates the intermediate step of 'reforming' methanol into hydrogen that is required in the Ballard process. Energy Ventures targets small niche markets such as small utility vehicles for its direct methanol fuel cell. A completely self-contained fuel cell of this type is expected to be ready in 2002. Solid oxide fuel cells for off-grid remote power units as well as for home heat and power is yet another field of development that will be particularly attractive to operations in remote areas where reliable grid electricity is expensive and hard to obtain. A prototype 2.3 kW residential power system using natural gas was made available by Global Thermoelectric Inc in June 2001; field testing is planned for 2002, with commercial production in late 2003 or 2004. The Calgary-based Snow Leopard Resources Inc plans to use pure hydrogen sulphide obtained from sour natural gas as a hydrogen source. The prime focus of Snow Leopard is on gas plants looking for ways to increase their efficiency, obtain carbon dioxide credits and generate electricity on site. This type of fuel cell also could be of interest to companies with shut-in sour gas since these companies could use the stationary fuel cell system to generate electricity.

  13. Learn About Stem Cells

    Science.gov (United States)

    ... Patient Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... original cell’s DNA, cytoplasm and cell membrane. About stem cells Stem cells are the foundation of development in ...

  14. Surface chemical immobilization of parylene C with thermosensitive block copolymer brushes based on N-isopropylacrylamide and N-tert-butylacrylamide: synthesis, characterization, and cell adhesion/detachment.

    Science.gov (United States)

    Zhang, Changhong; Vernier, P Thomas; Wu, Yu-Hsuan; Yang, Wangrong; Thompson, Mark E

    2012-01-01

    Poly(N-isopropylacrylamide) (pNIPAM), poly(N-tert-butylacrylamide) (pNTBAM), and their copolymer brushes were covalently immobilized onto parylene C (PC) surfaces via surface initiated atom transfer radical polymerization (ATRP). Contact angle measurement between 13 and 40°C showed that the hydrophobicity of the modified PC surfaces was thermally sensitive. Among these samples, PC grafted with pNIPAM (PC-NI), PC grafted with pNTBAM (PC-NT) and PC grafted with copolymer brushes containing pNTBAM and pNIPAM (PC-NT-NI) exhibited the lower critical solution temperature (LCST) at 29, 22, and 24°C, respectively. Cytocompatibility study for the modified surfaces was performed by 5 days human skin fibroblast culture at 37°C. Data showed that only a very small amount of cells adhered on the PC and PC-NI surfaces, while a significantly higher amount of cell adhesion and growth was observed on PC-NT and PC-NT-NI surfaces. Furthermore, cell detachment at the temperatures of 24 and 6°C were studied after the substrates were cultured with cells at 37°C for 24 h. The results showed that the cells on PC-NI formed the aggregations and loosely attached on the substrate after 30-min culture at 24°C, while no significant cell detachment was observed for PC-NT and PC-NT-NI samples at this temperature. By continuing the cell culture for additional 100 min at 6°C for PC-NT and PC-NT-NI, about 10 and 35% of the cells were found detached respectively, and the unattached cells aggregated on the substrate. In comparison, cells cultured on the tissue culture petri dish (TCP) exhibited no quantity and morphology changes at the culture temperatures of 37, 24, and 6°C. This study showed that: (1) immobilization of PC with nonthermal sensitive pNTBAM could provide PC surface thermal sensitive hydrophilicity; (2) the chlorines on the polymer brushes of PC-NT could be used to further initiate the ATRP pNIPAM and form block copolymer brushes; (3) the incorporation of pNTBAM into pNIPAM on PC

  15. Fuel cells

    Directory of Open Access Journals (Sweden)

    D. N. Srivastava

    1962-05-01

    Full Text Available The current state of development of fuel cells as potential power sources is reviewed. Applications in special fields with particular reference to military requirements are pointed out.

  16. Electrochemical cell

    Science.gov (United States)

    Nagy, Zoltan; Yonco, Robert M.; You, Hoydoo; Melendres, Carlos A.

    1992-01-01

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90.degree. in either direction while maintaining the working and counter electrodes submerged in the electrolyte.

  17. Fuel cells:

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2013-01-01

    A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil and nucl......A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil...

  18. CellTracks cell analysis system for rare cell detection

    NARCIS (Netherlands)

    Kagan, Michael T.; Trainer, Michael N.; Bendele, Teresa; Rao, Chandra; Horton, Allen; Tibbe, Arjan G.; Greve, Jan; Terstappen, Leon W.M.M.

    2002-01-01

    The CellTracks system is a Compact Disk-based cell analyzer that, similar to flow cytometry, differentiates cells that are aligned while passing through focused laser beams. In CellTracks, only immuno-magnetically labeled cells are aligned and remain in position for further analysis. This feature is

  19. Experimental investigation of air relative humidity (RH) cycling tests on MEA/cell aging in PEMFC. Pt. II. Study of low RH cycling test with air RH at 62%/0%

    Energy Technology Data Exchange (ETDEWEB)

    Huang, B.T.; Chatillon, Y.; Bonnet, C.; Lapicque, F. [Laboratoire Reactions et Genie des Procedes, CNRS-Nancy University, Nancy (France); Leclerc, S. [Laboratoire d' Energetique et de Mecanique Theorique et Appliquee, CNRS-Nancy University, Vandoeuvre-les-Nancy (France); Hinaje, M.; Rael, S. [Groupe de Recherche en Electrotechnique et Electronique de Nancy, Nancy University, Vandoeuvre-les-Nancy (France)

    2012-06-15

    The effect of low relative humidity (RH) cycling (RH{sub C} 62%/0%) on the degradation mechanisms of a single proton exchange membrane fuel cell (5 x 5 cm{sup 2}) was investigated and compared to a cell operated at constant humidification (RH{sub C} = 62%). The overall cell performance loss was near 33 {mu}V h{sup -1}, which is greater than the voltage decay under constant RH condition near 3 {mu}V h{sup -1}. The electroactive surface was reduced but to an acceptable level. Impedance spectroscopy revealed that the ohmic and charge transfer resistances were reduced by the likely improved hydration of the ionomeric layer at the catalyst due to hydrogen crossover. This was so important that H{sub 2} starvation was finally responsible for the collapse of the cell after 650 h. Transmission electron microscopy showed occurrence of various phenomena, e.g., bubbles and pinholes formation in the membrane due to local overheat from hydrogen combustion at the cathode, and thickness reduction of catalytic layers. The water up take obtained by {sup 1}H NMR within the membrane electrode assembly (MEA) after low RH cycling reduced by 24% compared to a fresh MEA. Observations are also compared to those obtained at high RH cycling (RH{sub C} 62%/100%) presented in Part I of this study [1]. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  20. Sickle Cell Anemia

    Science.gov (United States)

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells ... red blood cells. This leads to anemia. The sickle cells also get stuck in blood vessels, blocking blood ...

  1. Sickle Cell Disease

    Science.gov (United States)

    ... sickle cell disease?Sickle cell disease, also called sickle cell anemia, is a hereditary condition (which means it runs ... disease, hemoglobin SS disease, hemoglobin synthesis, hemoglobinopathies, ... cell anemia, sickle cell crisis, vaso-occlusive crisis Family Health, ...

  2. Stem Cell Information: Glossary

    Science.gov (United States)

    ... bone, cartilage, stromal cells that support blood formation, fat, and fibrous tissue. Cell-based therapies —Treatment in which stem cells are induced to differentiate into the specific cell type required to repair damaged or destroyed cells or ...

  3. Squamous Cell Carcinoma

    Science.gov (United States)

    ... Kids’ zone Video library Find a dermatologist Squamous cell carcinoma Overview Squamous cell carcinoma: This man's skin ... a squamous cell carcinoma on his face. Squamous cell carcinoma: Overview Squamous cell carcinoma (SCC) is a ...

  4. Electrochemical Cell

    DEFF Research Database (Denmark)

    1999-01-01

    The invention relates to a rechargeable electrochemical cell comprising a negative electrode, an electrolyte and a positive electrode in which the positive electrode structure comprises a lithium cobalt manganese oxide of the composition Li¿2?Co¿y?Mn¿2-y?O¿4? where 0

  5. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  6. Photovoltaic cell

    Science.gov (United States)

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  7. Fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, Hirofumi.

    1989-05-22

    This invention aims to maintain a long-term operation with stable cell output characteristics by uniformly supplying an electrolyte from the reserver to the matrix layer over the entire matrix layer, and further to prevent the excessive wetting of the catalyst layer by smoothly absorbing the volume change of the electrolyte, caused by the repeated stop/start-up of the fuel cell, within the reserver system. For this purpose, in this invention, an electrolyte transport layer, which connects with an electrolyte reservor formed at the electrode end, is partly formed between the electrode material and the catalyst layer; a catalyst layer, which faces the electrolyte transport layer, has through-holes, which connect to the matrix, dispersely distributed. The electrolyte-transport layer is a thin sheet of a hydrophilic fibers which are non-wovens of such fibers as carbon, silicon carbide, silicon nitride or inorganic oxides. 11 figs.

  8. Ghost cell lesions

    Directory of Open Access Journals (Sweden)

    E Rajesh

    2015-01-01

    Full Text Available Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms.

  9. [Inflammatory dendritic cells].

    Science.gov (United States)

    Segura, Elodie; Amigorena, Sebastian

    2014-01-01

    Dendritic cells are a rare and heterogeneous population of professional antigen-presenting cells. Several murine dendritic cell subpopulations have been identified that differ in their phenotype and functional properties. In the steady state, committed dendritic cell precursors differentiate into lymphoid organ-resident dendritic cells and migratory tissue dendritic cells. During inflammation appears an additional dendritic cell subpopulation that has been termed « inflammatory dendritic cells ». Inflammatory dendritic cells differentiate in situ from monocytes recruited to the site of inflammation. Here, we discuss how mouse inflammatory dendritic cells differ from macrophages and from other dendritic cell populations. Finally, we review recent work on human inflammatory dendritic cells.

  10. Red blood cells, sickle cell (image)

    Science.gov (United States)

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). ... abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  11. Red blood cells, multiple sickle cells (image)

    Science.gov (United States)

    Sickle cell anemia is an inherited disorder in which abnormal hemoglobin (the red pigment inside red blood cells) is produced. The abnormal hemoglobin causes red blood cells to assume a sickle shape, like the ones seen in this photomicrograph.

  12. CellFinder: a cell data repository

    OpenAIRE

    Stachelscheid, H.; Seltmann, S.; Lekschas, F.; Fontaine, J.F.; Mah, N.; Neves, M.; Andrade-Navarro, M.A.; Leser, U; Kurtz, A.

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue t...

  13. Molluscan cells in culture: primary cell cultures and cell lines

    OpenAIRE

    2013-01-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as bi...

  14. Stem Cell Basics

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... Basics » Stem Cell Basics I. Back to top Stem Cell Basics I. Introduction: What are stem cells, and ...

  15. Basal Cell Carcinoma

    Science.gov (United States)

    ... Kids’ zone Video library Find a dermatologist Basal cell carcinoma Overview Basal cell carcinoma: This skin cancer ... that has received years of sun exposure. Basal cell carcinoma: Overview Basal cell carcinoma (BCC) is the ...

  16. Electrorefining cell evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bronson, M.C.; Thomas, R.L. (ed.)

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  17. Antiparietal cell antibody test

    Science.gov (United States)

    APCA; Anti-gastric parietal cell antibody; Atrophic gastritis - anti-gastric parietal cell antibody; Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; ...

  18. Molluscan cells in culture: primary cell cultures and cell lines.

    Science.gov (United States)

    Yoshino, T P; Bickham, U; Bayne, C J

    2013-06-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as biomonitors for environmental contaminants, as models for gene transfer technologies, and for studies of innate immunity and neoplastic disease. Despite efforts to isolate proliferative cell lines from molluscs, the snail Biomphalaria glabrata Say, 1818 embryonic (Bge) cell line is the only existing cell line originating from any molluscan species. Taking an organ systems approach, this review summarizes efforts to establish molluscan cell cultures and describes the varied applications of primary cell cultures in research. Because of the unique status of the Bge cell line, an account is presented of the establishment of this cell line, and of how these cells have contributed to our understanding of snail host-parasite interactions. Finally, we detail the difficulties commonly encountered in efforts to establish cell lines from molluscs and discuss how these difficulties might be overcome.

  19. DNA-cell conjugates

    Science.gov (United States)

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  20. Molecular Mechanisms of Cell-cell Recognition

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-Huai

    2004-01-01

    Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.

  1. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  2. Photoelectrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Rauh, R. David (Newton, MA); Boudreau, Robert A. (Norton, MA)

    1983-06-14

    A photoelectrochemical cell comprising a sealed container having a light-transmitting window for admitting light into the container across a light-admitting plane, an electrolyte in the container, a photoelectrode in the container having a light-absorbing surface arranged to receive light from the window and in contact with the electrolyte, the surface having a plurality of spaced portions oblique to the plane, each portion having dimensions at least an order of magnitude larger than the maximum wavelength of incident sunlight, the total surface area of the surface being larger than the area of the plane bounded by the container, and a counter electrode in the container in contact with the electrolyte.

  3. nduced pluripotent stem cells and cell therapy

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2013-12-01

    Full Text Available Human embryonic stem cells are derived from the inner cell mass of a blastocyst-stage embryo. They hold a huge promise for cell therapy with their self-renewing ability and pluripotency, which is known as the potential to differentiate into all cell types originating from three embryonic germ layers. However, their unique pluripotent feature could not be utilised for therapeutic purposes due to the ethical and legal problems during derivation. Recently, it was shown that the cells from adult tissues could be reverted into embryonic state, thereby restoring their pluripotent feature. This has strenghtened the possiblity of directed differentition of the reprogrammed somatic cells into the desired cell types in vitro and their use in regenerative medicine. Although these cells were termed as induced pluripotent cells, the mechanism of pluripotency has yet to be understood. Still, induced pluripotent stem cell technology is considered to be significant by proposing novel approaches in disease modelling, drug screening and cell therapy. Besides their self-renewing ability and their potential to differentiate into all cell types in a human body, they arouse a great interest in scientific world by being far from the ethical concerns regarding their embryonic counterparts and their unique feature of being patient-specific in prospective cell therapies. In this review, induced pluripotent stem cell technology and its role in cell-based therapies from past to present will be discussed. J Clin Exp Invest 2013; 4 (4: 550-561

  4. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; Wang, S.; Wang, Y; Wang, X-N.

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ‘entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  5. Tumor cell "dead or alive": caspase and survivin regulate cell death, cell cycle and cell survival.

    Science.gov (United States)

    Suzuki, A; Shiraki, K

    2001-04-01

    Cell death and cell cycle progression are two sides of the same coin, and these two different phenomenons are regulated moderately to maintain the cellular homeostasis. Tumor is one of the disease states produced as a result of the disintegrated regulation and is characterized as cells showing an irreversible progression of cell cycle and a resistance to cell death signaling. Several investigations have been performed for the understanding of cell death or cell cycle, and cell death research has remarkably progressed in these 10 years. Caspase is a nomenclature referring to ICE/CED-3 cysteine proteinase family and plays a central role during cell death. Recently, several investigations raised some possible hypotheses that caspase is also involved in cell cycle regulation. In this issue, therefore, we review the molecular basis of cell death and cell cycle regulated by caspase in tumor, especially hepatocellular carcinoma cells.

  6. Cell culture purity issues and DFAT cells

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Shengjuan [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi Province 712100 (China); Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States); Bergen, Werner G. [Program in Cellular and Molecular Biosciences/Department of Animal Sciences, Auburn University, Auburn, AL 36849 (United States); Hausman, Gary J. [Animal Science Department, University of Georgia, Athens, GA 30602-2771 (United States); Zan, Linsen, E-mail: zanls@yahoo.com.cn [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi Province 712100 (China); Dodson, Michael V., E-mail: dodson@wsu.edu [Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States)

    2013-04-12

    Highlights: •DFAT cells are progeny cells derived from dedifferentiated mature adipocytes. •Common problems in this research is potential cell contamination of initial cultures. •The initial cell culture purity is crucial in DFAT cell research field. -- Abstract: Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  7. A comparative study on poly(xylitol sebacate) and poly(glycerol sebacate): mechanical properties, biodegradation and cytocompatibility.

    Science.gov (United States)

    Li, Yuan; Huang, Wenchao; Cook, Wayne D; Chen, Qizhi

    2013-06-01

    In order to develop degradable elastomers with a satisfactory combination of flexibility and enzyme-mediated degradation rate, the mechanical properties, enzymatic degradation kinetics and biocompatibility of poly(xylitol sebcate) (PXS) has been systematically investigated in comparison with poly(glycerol sebacate) (PGS). Under the same level of crosslinked density, the PXS elastomer networks have approximately twice the stretchability (elongation at break) of their PGS counterparts. This observation is attributable to the relatively longer and more orientable xylitol monomers, compared with glycerol molecules. Although xylitol monomers have two more hydroxyl groups, we, surprisingly, found that the hydrophilic side chains did not accelerate the water attack on the ester bonds of the PXS network, compared with their PGS counterpart. This observation was attributed to a steric hindrance effect, i.e. the large-sized hydroxyl groups can shield ester bonds from the attack of water molecules. In conclusion, the use of polyols of more than three -OH groups is an effective approach enhancing flexibility, whilst maintaining the degradation rate of polyester elastomers. Further development could be seen in the copolymerization of PPS with appropriate thermoplastic polyesters, such as poly(lactic acid) and polyhydroxyalkanoate.

  8. Green electrospun grape seed extract-loaded silk fibroin nanofibrous mats with excellent cytocompatibility and antioxidant effect.

    Science.gov (United States)

    Lin, Si; Chen, Mengxia; Jiang, Huayue; Fan, Linpeng; Sun, Binbin; Yu, Fan; Yang, Xingxing; Lou, Xiangxin; He, Chuanglong; Wang, Hongsheng

    2016-03-01

    Silk fibroin (SF) from Bombyx mori has an excellent biocompatibility and thus be widely applied in the biomedical field. Recently, various SF-based composite nanofibers have been developed for more demanding applications. Additionally, grape seed extract (GSE) has been demonstrated to be powerful on antioxidation. In the present study, we dedicate to fabricate a GSE-loaded SF/polyethylene oxide (PEO) composite nanofiber by green electrospinning. Our results indicated the successful loading of GSE into the SF/PEO composite nanofibers. The introduction of GSE did not affect the morphology of the SF/PEO nanofibers and GSE can be released from the nanofibers with a sustained manner. Furthermore, comparing with the raw SF/PEO nanofibrous mats, the GSE-loaded SF/PEO nanofibrous mats significantly enhanced the proliferation of the skin fibroblasts and also protected them against the damage from tert-butyl hydroperoxide-induced oxidative stress. All these findings suggest a promising potential of this novel GSE-loaded SF/PEO composite nanofibrous mats applied in skin care, tissue regeneration and wound healing.

  9. Electrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Heuts, J.J.F.G.; Willems, J.J.G.S.A.

    1987-10-13

    An electrochemical cell is described comprising a negative electrode. The electrochemically active material of which consists of an intermetallic compound forming a hydride with hydrogen, which compound has the CaCu/sub 5/-structure and the compositional formula AB/sub m/C/sub n/, where m+n is between 4.8 and 5.4, where n is between 0.05 and 0.6, in which A consists of Misch-metal or of one or more elements selected from the group consisting of Y, Ti, Hf, Zr, Ca, Th, La and the remaining rare earth metals, in which the total atomic quantities of the elements Y, Ti, Hf and Zr may not be more than 40% of A. B consists of two or more elements selected from the group formed by Ni, Co, Cu, Fe and Mn, where the maximum atomic quantity per gram atom of A is for Ni: 3.5, for Co:3.5, for Cu:3.5, for Fe:2.0 and for Mn:1.0, and C consists of one or more elements selected from the group formed by Al, Cr and Si in the indicated atomic quantities: Al:0.05-0.6, Cr:0.05-0.5 and Si:0.05-0.5, characterized in that the electrochemically active material additionally comprises one or more metals selected from the group formed by Pd, Pt, Ir and Rh, the atomic quantity per gram atom of A being from 0.001 to 0.5.

  10. CELL RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    REVIEWSInducible resistance to Fas-mediated apoptosis in B cells…………………………………ROTHSTEIN Thomas L (245)Executionary pathway for apoptosis: lessons from mutant mice………………………………………WOO Minna, Razqallah Hakem, Tak W Mak (267)The SHP-2 tyrosine phosphatase: Signaling mechanisms and biological functions…………………………………QU Cheng Kui (279)REGULAR ARTICLESTemperature dependent expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis…………………………KONG Wei Hua, Zheng GU, Jining LU, Jiake TSO (289)Transgenic mice overexpressing γ-aminobutyric acid transporter subtype I develop obesity…………………………………MA Ying Hua, Jia Hua HU, Xiao Gang ZHOU, Ruo Wang ZENG, Zhen Tong MEI, Jian FEI, Li He GUO (303)Genetic aberration in primary hepatocellular carcinoma: correlation between p53 gene mutation and loss-of-heterozygosity on chromosome 16q21-q23 and 9p21-p23………………………………………WANG Gang, Chang Hui HUANG, Yan ZHAO, Ling CAI, Ying WANG, Shi Jin XIU, Zheng Wen JIANG, Shuang YANG, Xin Tai ZHAO, Wei HUANG, Jian Ren GU (311)Identification and genetic mapping of four novel genes that regulate leaf deve- lopment in Arabidopsis………………………………………………SUN Yue, Wei ZHANG, Feng Ling LI, Ying Li GUO, Tian Lei LIU, Hai HUANG (325)NOTICE FOR CONTRIBUTORS…………………………………(337)CONTENTS of Vol. 10, 2000…………………………………………………(338)

  11. Cell culture purity issues and DFAT cells.

    Science.gov (United States)

    Wei, Shengjuan; Bergen, Werner G; Hausman, Gary J; Zan, Linsen; Dodson, Michael V

    2013-04-12

    Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  12. Cell Membrane Softening in Cancer Cells

    Science.gov (United States)

    Schmidt, Sebastian; Händel, Chris; Käs, Josef

    Biomechanical properties are useful characteristics and regulators of the cell's state. Current research connects mechanical properties of the cytoskeleton to many cellular processes but does not investigate the biomechanics of the plasma membrane. We evaluated thermal fluctuations of giant plasma membrane vesicles, directly derived from the plasma membranes of primary breast and cervical cells and observed a lowered rigidity in the plasma membrane of malignant cells compared to non-malignant cells. To investigate the specific role of membrane rigidity changes, we treated two cell lines with the Acetyl-CoA carboxylase inhibitor Soraphen A. It changed the lipidome of cells and drastically increased membrane stiffness by up regulating short chained membrane lipids. These altered cells had a decreased motility in Boyden chamber assays. Our results indicate that the thermal fluctuations of the membrane, which are much smaller than the fluctuations driven by the cytoskeleton, can be modulated by the cell and have an impact on adhesion and motility.

  13. Mammary stem cells have myoepithelial cell properties.

    Science.gov (United States)

    Prater, Michael D; Petit, Valérie; Alasdair Russell, I; Giraddi, Rajshekhar R; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F; Metzger, Daniel; Faraldo, Marisa M; Deugnier, Marie-Ange; Glukhova, Marina A; Stingl, John

    2014-10-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt actin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using two independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage-tracing approach we follow the progeny of myoepithelial cells that express α-smooth muscle actin and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy.

  14. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL) Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  15. Cell sheet engineering

    Directory of Open Access Journals (Sweden)

    Masayuki Yamato

    2004-05-01

    Full Text Available We have developed ‘cell sheet engineering’ in order to avoid the limitations of tissue reconstruction using biodegradable scaffolds or single cell suspension injection. Our concept is tissue reconstruction, not from single cells, but from cell sheets. Cell sheets are prepared using temperature-responsive culture dishes. Temperature-responsive polymers are covalently grafted onto the dishes, allowing various types of cells to adhere and proliferate at 37°C. The cells spontaneously detach when the temperature is reduced below 32°C without the need for proteolytic enzymes. The confluent cells are noninvasively harvested as single, contiguous cell sheets with intact cell-cell junctions and deposited extracellular matrix (ECM. We have used these harvested cell sheets for various tissue reconstructions, including ocular surfaces, periodontal ligaments, cardiac patches, and bladder augmentation.

  16. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  17. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL)Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  18. Fuel cells: A survey

    Science.gov (United States)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  19. CellFinder: a cell data repository.

    Science.gov (United States)

    Stachelscheid, Harald; Seltmann, Stefanie; Lekschas, Fritz; Fontaine, Jean-Fred; Mah, Nancy; Neves, Mariana; Andrade-Navarro, Miguel A; Leser, Ulf; Kurtz, Andreas

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue types from RNA-seq and microarrays and 553 905 protein expressions for 535 cells/tissues. Text mining of a corpus of >2000 publications followed by manual curation confirmed expression information on ∼900 proteins and genes. CellFinder's data model is capable to seamlessly represent entities from single cells to the organ level, to incorporate mappings between homologous entities in different species and to describe processes of cell development and differentiation. Its ontological backbone currently consists of 204 741 ontology terms incorporated from 10 different ontologies unified under the novel CELDA ontology. CellFinder's web portal allows searching, browsing and comparing the stored data, interactive construction of developmental trees and navigating the partonomic hierarchy of cells and tissues through a unique body browser designed for life scientists and clinicians.

  20. Snail modulates cell metabolism in MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  1. Cell aggregation and sedimentation.

    Science.gov (United States)

    Davis, R H

    1995-01-01

    The aggregation of cells into clumps or flocs has been exploited for decades in such applications as biological wastewater treatment, beer brewing, antibiotic fermentation, and enhanced sedimentation to aid in cell recovery or retention. More recent research has included the use of cell aggregation and sedimentation to selectively separate subpopulations of cells. Potential biotechnological applications include overcoming contamination, maintaining plasmid-bearing cells in continuous fermentors, and selectively removing nonviable hybridoma cells from perfusion cultures.

  2. Cell control report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This extensive report provides an essential overview of cells and their use as factory automation building blocks. The following issues are discussed in depth: Cell integration Cell software and standards Future technologies applied to cells Plus Cell control applications including: - rotary parts manufacturing - diesel engine component development - general cell control development at the General Electric Corporation - a vendor list.

  3. Nanostructured Solar Cells

    Science.gov (United States)

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-01-01

    We are glad to announce the Special Issue “Nanostructured Solar Cells”, published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  4. Squamous cell skin cancer

    Science.gov (United States)

    ... that reflect light more, such as water, sand, concrete, and areas that are painted white. The higher ... - skin - squamous cell; Skin cancer - squamous cell; Nonmelanoma skin cancer - squamous ...

  5. Cell mechanics: a dialogue

    Science.gov (United States)

    Tao, Jiaxiang; Li, Yizeng; Vig, Dhruv K.; Sun, Sean X.

    2017-03-01

    Under the microscope, eukaryotic animal cells can adopt a variety of different shapes and sizes. These cells also move and deform, and the physical mechanisms driving these movements and shape changes are important in fundamental cell biology, tissue mechanics, as well as disease biology. This article reviews some of the basic mechanical concepts in cells, emphasizing continuum mechanics description of cytoskeletal networks and hydrodynamic flows across the cell membrane. We discuss how cells can generate movement and shape changes by controlling mass fluxes at the cell boundary. These mass fluxes can come from polymerization/depolymerization of actin cytoskeleton, as well as osmotic and hydraulic pressure-driven flow of water across the cell membrane. By combining hydraulic pressure control with force balance conditions at the cell surface, we discuss a quantitative mechanism of cell shape and volume control. The broad consequences of this model on cell mechanosensation and tissue mechanics are outlined.

  6. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  7. T-Cell Lymphoma

    Science.gov (United States)

    Getting the Facts T-Cell Lymphoma Overview Lymphoma is the most common blood cancer. The two main forms of lymphoma are Hodgkin lymphoma ... develop into lymphomas: B-lymphocytes (B-cells) and T-lymphocytes (T-cells). T-cell lymphomas account for ...

  8. Tracking adult stem cells

    NARCIS (Netherlands)

    Snippert, H.J.G.; Clevers, H.

    2011-01-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context,

  9. Insect Cell Culture

    NARCIS (Netherlands)

    Oers, van M.M.; Lynn, D.E.

    2010-01-01

    Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from lepidoptera

  10. Ganglion cell like cells, diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Anand Shankar Ammanagi

    2013-01-01

    Full Text Available We report a case of cutaneous swelling found on the left anterior axillary fold of a 41-year-old man. Gross examination of specimen excised from the dermis showed a well-circumscribed nodule histologically composed of spindle cells with interspersed ganglion cell like cells. On hematoxylin and eosine (H and E staining it was diagnosed as ganglioneuroma. Ganglioneuromas are rare, benign, fully differentiated tumors that contain mature schwann cells, ganglion cells, fibrous tissue, and nerve fibers. They are commonly found along the paravertebral sympathetic ganglia and sometimes in the adrenal medulla. However primary cutaneous ganglioneuroma is an extremely rare tumor. Immunohistochemical workup revealed a fibroblastic origin and hence the case was diagnosed as fibromatosis with ganglion cell like fibroblasts. This case report suggests that the features considered diagnostic of ganglioneuromas can occur in other cutaneous lesions and, therefore, this diagnosis cannot be offered only on the basis of H and E.

  11. Generation of iPS Cells from Granulosa Cells.

    Science.gov (United States)

    Mao, Jian; Liu, Lin

    2016-01-01

    Various types of somatic cells can be reprogrammed to induced pluripotent stem (iPS) cells. Somatic stem cells may generate iPS cells more efficiently than do differentiated cells. We show that granulosa cells exhibit characteristic of somatic stem cells and can be reprogrammed to iPS cells more efficiently or with few factors. Here, we describe generation of mouse and pig iPS cells from granulosa cells with high efficiency.

  12. B cell helper assays.

    Science.gov (United States)

    Abrignani, Sergio; Tonti, Elena; Casorati, Giulia; Dellabona, Paolo

    2009-01-01

    Activation, proliferation and differentiation of naïve B lymphocytes into memory B cells and plasma cells requires engagement of the B cell receptor (BCR) coupled to T-cell help (1, 2). T cells deliver help in cognate fashion when they are activated upon recognition of specific MHC-peptide complexes presented by B cells. T cells can also deliver help in a non-cognate or bystander fashion, when they do not find specific MHC-peptide complexes on B cells and are activated by alternative mechanisms. T-cell dependent activation of B cells can be studied in vitro by experimental models called "B cell helper assays" that are based on the co-culture of B cells with activated T cells. These assays allow to decipher the molecular bases for productive T-dependent B cell responses. We show here examples of B cell helper assays in vitro, which can be reproduced with any subset of T lymphocytes that displays the appropriate helper signals.

  13. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    Science.gov (United States)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  14. Sertoli-Leydig cell tumor

    Science.gov (United States)

    Sertoli-stromal cell tumor; Arrhenoblastoma; Androblastoma; Ovarian cancer - Sertoli-Leydig cell tumor ... The Sertoli cells are normally located in the male reproductive glands (the testes). They feed sperm cells. The Leydig cells, also ...

  15. Single cell mechanics of keratinocyte cells.

    Science.gov (United States)

    Lulevich, Valentin; Yang, Hsin-ya; Isseroff, R Rivkah; Liu, Gang-yu

    2010-11-01

    Keratinocytes represent the major cell type of the uppermost layer of human skin, the epidermis. Using AFM-based single cell compression, the ability of individual keratinocytes to resist external pressure and global rupturing forces is investigated and compared with various cell types. Keratinocytes are found to be 6-70 times stiffer than other cell types, such as white blood, breast epithelial, fibroblast, or neuronal cells, and in contrast to other cell types they retain high mechanic strength even after the cell's death. The absence of membrane rupturing peaks in the force-deformation profiles of keratinocytes and their high stiffness during a second load cycle suggests that their unique mechanical resistance is dictated by the cytoskeleton. A simple analytical model enables the quantification of Young's modulus of keratinocyte cytoskeleton, as high as 120-340 Pa. Selective disruption of the two major cytoskeletal networks, actin filaments and microtubules, does not significantly affect keratinocyte mechanics. F-actin is found to impact cell deformation under pressure. During keratinocyte compression, the plasma membrane stretches to form peripheral blebs. Instead of blebbing, cells with depolymerized F-actin respond to pressure by detaching the plasma membrane from the cytoskeleton underneath. On the other hand, the compression force of keratinocytes expressing a mutated keratin (cell line, KEB-7) is 1.6-2.2 times less than that for the control cell line that has normal keratin networks. Therefore, we infer that the keratin intermediate filament network is responsible for the extremely high keratinocyte stiffness and resilience. This could manifest into the rugged protective nature of the human epidermis.

  16. Plant stem cell niches.

    Science.gov (United States)

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  17. Lung Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Sharon R. Pine

    2008-01-01

    Full Text Available Lung cancer remains a major cause of cancer-related lethality because of high incidence and recurrence in spite of significant advances in staging and therapies. Recent data indicates that stem cells situated throughout the airways may initiate cancer formation. These putative stem cells maintain protumorigenic characteristics including high proliferative capacity, multipotent differentiation, drug resistance and long lifespan relative to other cells. Stem cell signaling and differentiation pathways are maintained within distinct cancer types, and destabilization of this machinery may participate in maintenance of cancer stem cells. Characterization of lung cancer stem cells is an area of active research and is critical for developing novel therapies. This review summarizes the current knowledge on stem cell signaling pathways and cell markers used to identify the lung cancer stem cells.

  18. What are Stem Cells?

    Directory of Open Access Journals (Sweden)

    Ahmadshah Farhat

    2014-05-01

    Full Text Available   Stem cells are undifferentiated self regenerating multi potential cells. There are three types of stem cells categories by the ability to form after cells and correlated with the body’s development process. Totipotent: these stem cells can form an entire organism such as fertilized egg. Ploripotent: ploripotent cells are those that can form any cell in the body but cannot form an entire organism such as developing embryo’s totipotent cells become ploripotent  Multipotent: Multi potent stem cells are those that can only form specific cells in the body such as blood cells based. Based on the sources of stem cells we have three types of these cells: Autologous: Sources of the patient own cells are (Autologous either the cells from patient own body or his or her cord blood. For this type of transplant the physician now usually collects the periphery rather than morrow because the procedure is easier on like a bane morrow harvest it take place outside of an operating room, and the patient does not to be under general unsetting . Allogenic: Sources of stem cells from another donore are primarily relatives (familial allogenic or completely unrelated donors. Xenogenic: In these stem cells from different species are transplanted e .g striatal porcine fetal mesan cephalic (FVM xenotransplants for Parkinson’s disease. On sites of isolation such as embryo, umbilical cord and other body tissues stem cells are named embnyonic, cord blood, and adult stem cells. The scope of results and clinical application of stem cells are such as: Neurodegenerative conditions (MS,ALS, Parkinson’s, Stroke, Ocular disorders- Glaucoma, retinitis Pigmentosa (RP, Auto Immune Conditions (Lupus, MS,R. arthritis, Diabetes, etc, Viral Conditions (Hepatitis C and AIDS, Heart Disease, Adrenal Disorders, Injury(Nerve, Brain, etc, Anti aging (hair, skin, weight control, overall well being/preventive, Emotional disorders, Organ / Tissue Cancers, Blood cancers, Blood diseases

  19. Tracking adult stem cells.

    Science.gov (United States)

    Snippert, Hugo J; Clevers, Hans

    2011-02-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context, rather than outside their natural environment. The mouse is an attractive model in which to study adult mammalian stem cells, as numerous experimental systems and genetic tools are available. In this review, we describe strategies commonly used to identify and functionally characterize adult stem cells in mice and discuss their potential, limitations and interpretations, as well as how they have informed our understanding of adult stem-cell biology. An accurate interpretation of physiologically relevant stem-cell assays is crucial to identify adult stem cells and elucidate how they self-renew and give rise to differentiated progeny.

  20. Stem cells in urology.

    Science.gov (United States)

    Aboushwareb, Tamer; Atala, Anthony

    2008-11-01

    The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

  1. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    Directory of Open Access Journals (Sweden)

    Quanwen Liu

    2016-01-01

    Full Text Available In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment.

  2. Cell shape recognition by colloidal cell imprints

    NARCIS (Netherlands)

    Borovička, Josef; Stoyanov, S.D.; Paunov, V.N.

    2015-01-01

    The results presented in this study are aimed at the theoretical estimate of the interactions between a spherical microbial cell and the colloidal cell imprints in terms of the Derjaguin, Landau, Vervey, and Overbeek (DLVO) surface forces. We adapted the Derjaguin approximation to take into accou

  3. Pluripotent Stem Cells for Schwann Cell Engineering

    NARCIS (Netherlands)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-01-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitu

  4. Are mesenchymal stromal cells immune cells?

    NARCIS (Netherlands)

    M.J. Hoogduijn (Martin)

    2015-01-01

    textabstractMesenchymal stromal cells (MSCs) are considered to be promising agents for the treatment of immunological disease. Although originally identified as precursor cells for mesenchymal lineages, in vitro studies have demonstrated that MSCs possess diverse immune regulatory capacities. Pre-cl

  5. The cell cycle as a brake for β-cell regeneration from embryonic stem cells.

    Science.gov (United States)

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-13

    The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle machinery. Both β cells and ES cells possess unique cell cycle machinery yet with significant contrasts. In this review, we compare the cell cycle control mechanisms in both ES cells and β cells, and highlight the fundamental differences between pluripotent cells of embryonic origin and differentiated β cells. Through critical analysis of the differences of the cell cycle between these two cell types, we propose that the cell cycle of ES cells may act as a brake for β-cell regeneration. Based on these differences, we discuss the potential of modulating the cell cycle of ES cells for the large-scale generation of functionally mature β cells in vitro. Further understanding of the factors that modulate the ES cell cycle will lead to new approaches to enhance the production of functional mature insulin-producing cells, and yield a reliable system to generate bona fide β cells in vitro.

  6. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  7. FUEL CELL ELECTRODE MATERIALS

    Science.gov (United States)

    FUEL CELL ELECTRODE MATERIALS. RAW MATERIAL SELECTION INFLUENCES POLARIZATION BUT IS NOT A SINGLE CONTROLLING FACTOR. AVAILABLE...DATA INDICATES THAT AN INTERRELATIONSHIP OF POROSITY, AVERAGE PORE VOLUME, AND PERMEABILITY CONTRIBUTES TO ELECTRODE FUEL CELL BEHAVIOR.

  8. NIA Aging Cell Repository

    Data.gov (United States)

    Federal Laboratory Consortium — To facilitate aging research on cells in culture, the NIA provides support for the NIA Aging Cell Repository, located at the Coriell Institute for Medical Research...

  9. Cell signaling review series

    Institute of Scientific and Technical Information of China (English)

    Aiming Lin; Zhenggang Liu

    2008-01-01

    @@ Signal transduction is pivotal for many, if not all, fundamental cellular functions including proliferation, differentiation, transformation and programmed cell death. Deregulation of cell signaling may result in certain types of cancers and other human diseases.

  10. Stem Cell Transplant

    Science.gov (United States)

    ... transplant is a procedure that infuses healthy blood stem cells into your body to replace your damaged or ... A bone marrow transplant is also called a stem cell transplant. A bone marrow transplant may be necessary ...

  11. Sickle cell test

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003666.htm Sickle cell test To use the sharing features on this page, please enable JavaScript. The sickle cell test looks for the abnormal hemoglobin in the ...

  12. Sickle Cell Tests

    Science.gov (United States)

    ... AACC products and services. Advertising & Sponsorship: Policy | Opportunities Sickle Cell Tests Share this page: Was this page helpful? ... else I should know? How is it used? Sickle cell tests are used to identify the presence of ...

  13. Sickle Cell Disease Quiz

    Science.gov (United States)

    ... Websites About Us Information For... Media Policy Makers Sickle Cell Disease Quiz Language: English Español (Spanish) Recommend on ... 1. True or False: Only African Americans get sickle cell disease. A True B False 2. True or ...

  14. Sickle Cell Trait

    Science.gov (United States)

    ... Websites About Us Information For... Media Policy Makers Sickle Cell Trait Language: English Español (Spanish) Recommend on Facebook ... pass the trait on to their children. How Sickle Cell Trait is Inherited If both parents have SCT, ...

  15. Sickle cell anemia.

    OpenAIRE

    ŘÍHOVÁ, Tereza

    2013-01-01

    This thesis is about the disease called sickle cell anemia, or drepanocytosis. In this thesis is described the history of the disease, pathophysiology, laboratory features, various clinical features, diferencial diagnosis, quality of life in sickle cell anemia and therapy.

  16. Giant Cell Arteritis

    Science.gov (United States)

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  17. White Blood Cell Count

    Science.gov (United States)

    ... limited. Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? ... Count; Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , ...

  18. Sickle Cell Information Center

    Science.gov (United States)

    ... Nature, Wash Post, SciAm, CNN - Google Custom Search Sickle Cell Anemia News -- ScienceDaily January 18, 1970 Read articles summarizing medical research on sickle-cell anemia. NYT, Nature, Wash Post, SciAm, CNN - Google Custom ...

  19. Sickle Cell Disease

    Science.gov (United States)

    ... About Us Overview of CDC’s work. Advancements in Sickle Cell Disease New supplement from the American Journal of Preventive Medicine describes the state of sickle cell disease related care in the United States. Read Supplement ...

  20. Red blood cell production

    Science.gov (United States)

    ... to one part of the body or another. Red blood cells are an important element of blood. Their job ... is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of ...

  1. Cell phone explosion.

    Science.gov (United States)

    Atreya, Alok; Kanchan, Tanuj; Nepal, Samata; Pandey, Bhuwan Raj

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging.

  2. Mast cell proteoglycans.

    Science.gov (United States)

    Rönnberg, Elin; Melo, Fabio R; Pejler, Gunnar

    2012-12-01

    Mast cells are versatile effector cells of the immune system, contributing to both innate and adaptive immunity toward pathogens but also having profound detrimental activities in the context of inflammatory disease. A hallmark morphological feature of mast cells is their large content of cytoplasmic secretory granules, filled with numerous secretory compounds, including highly negatively charged heparin or chondroitin sulfate proteoglycans of serglycin type. These anionic proteoglycans provide the basis for the strong metachromatic staining properties of mast cells seen when applying various cationic dyes. Functionally, the mast cell proteoglycans have been shown to have an essential role in promoting the storage of other granule-contained compounds, including bioactive monoamines and different mast cell-specific proteases. Moreover, granule proteoglycans have been shown to regulate the enzymatic activities of mast cell proteases and to promote apoptosis. Here, the current knowledge of mast cell proteoglycans is reviewed.

  3. Diagram of Cell to Cell Communication

    Science.gov (United States)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  4. STEM CELLS AND PROTEOMICS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yong-ming; GUO Tian-nan; HUANG Shi-ang

    2006-01-01

    The distinctive features of proteomics are large-scale and high throughput. The key techniques of proteomics are two-dimensional gel electrophoresis, mass spectrometry and bioinformatics. Stem cell can differentiate into all kinds of cells, tissues and organs. There are many proteins and cytokines involved in the process of differentiation. Applying proteomics techniques to the research of the complex process of stem cell differentiation is of great importance to study the mechanism and applications of stem cell differentiation.

  5. Kidney Cell Electrophoresis

    Science.gov (United States)

    Todd, P.

    1985-01-01

    Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated, ground support in the form of analytical cell electrophoresis and flow cytometry was provided and cells returned from space flight were analyzed. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. The protocol established and utilized is given.

  6. Fish stem cell cultures.

    Science.gov (United States)

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  7. Fish Stem Cell Cultures

    Directory of Open Access Journals (Sweden)

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Full Text Available Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  8. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  9. Storage of cell lines.

    Science.gov (United States)

    Parker, Katharine A

    2011-01-01

    The successful storage of cell lines depends upon many factors, including the condition of the cells to be frozen and the experience of the operator. Attempting to freeze down unhealthy, contaminated or poorly labelled cells can have huge implications for a research laboratory. This chapter outlines the importance of good record keeping, vigilant monitoring, aseptic technique, and high-quality reagents in the successful storage and downstream propagation of cell lines.

  10. Skeletal (stromal) stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Kermani, Abbas Jafari; Zaher, Walid

    2015-01-01

    Skeletal (marrow stromal) stem cells (BMSCs) are a group of multipotent cells that reside in the bone marrow stroma and can differentiate into osteoblasts, chondrocytes and adipocytes. Studying signaling pathways that regulate BMSC differentiation into osteoblastic cells is a strategy....../preadipocyte factor 1 (Dlk1/Pref-1), the Wnt co-receptor Lrp5 and intracellular kinases. This article is part of a Special Issue entitled: Stem Cells and Bone....

  11. Stem cell heterogeneity revealed

    DEFF Research Database (Denmark)

    Andersen, Marianne S; Jensen, Kim B

    2016-01-01

    The skin forms a protective, water-impermeable barrier consisting of heavily crosslinked epithelial cells. However, the specific role of stem cells in sustaining this barrier remains a contentious issue. A detailed analysis of the interfollicular epidermis now proposes a model for how a composite...... of cells with different properties are involved in its maintenance....

  12. Advanced Cell Technology, Inc.

    Science.gov (United States)

    Caldwell, William M

    2007-03-01

    Advanced Cell Technology, Inc. (OTCBB: ACTC) is a biotechnology company applying novel human embryonic stem cell technologies in the emerging field of regenerative medicine. We believe that regenerative medicine has the potential to revolutionize the field by enabling scientists to produce human cells of any kind for use in a wide array of therapies.

  13. Adventures with Cell Phones

    Science.gov (United States)

    Kolb, Liz

    2011-01-01

    Teachers are finding creative ways to turn the basic cell phone from a digital distraction into a versatile learning tool. In this article, the author explains why cell phones are important in learning and suggests rather than banning them that they be integrated into learning. She presents activities that can be done on a basic cell phone with a…

  14. Cell phones and cancer

    Science.gov (United States)

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  15. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  16. Dazlin' pluripotent stem cells

    NARCIS (Netherlands)

    Welling, M.A.

    2014-01-01

    Pluripotent embryonic stem cells (ESCs) can be isolated from the inner cell mass (ICM) of blastocyst embryos and differentiate into all three germ layers in vitro. However, despite their similar origin, mouse embryonic stem cells represent a more naïve ICM-like pluripotent state whereas human embryo

  17. Mammalian Cell Culture Simplified.

    Science.gov (United States)

    Moss, Robert; Solomon, Sondra

    1991-01-01

    A tissue culture experiment that does not require elaborate equipment and that can be used to teach sterile technique, the principles of animal cell line maintenance, and the concept of cell growth curves is described. The differences between cancerous and normal cells can be highlighted. The procedure is included. (KR)

  18. Cell Culture Made Easy.

    Science.gov (United States)

    Dye, Frank J.

    1985-01-01

    Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

  19. SYNOVIAL CELL SARCOMA

    Directory of Open Access Journals (Sweden)

    M. Farzan

    1997-06-01

    Full Text Available Ten cases of synovial cell sarcoma are reported. The youngest patient was a 2'A years old boy with synovial cell sarcoma of the knee and the oldest one was a man with synovial cell sarcoma of the elbow.

  20. Embryonic Stem Cell Markers

    Directory of Open Access Journals (Sweden)

    Lan Ma

    2012-05-01

    Full Text Available Embryonic stem cell (ESC markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM technique and magnetic cell sorting (MACS are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs, which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells.

  1. Mouse Leydig Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo-Syong Pan

    2011-01-01

    Full Text Available Cordycepin is a natural pure compound extracted from Cordyceps sinensis (CS. We have demonstrated that CS stimulates steroidogenesis in primary mouse Leydig cell and activates apoptosis in MA-10 mouse Leydig tumor cells. It is highly possible that cordycepin is the main component in CS modulating Leydig cell functions. Thus, our aim was to investigate the steroidogenic and apoptotic effects with potential mechanism of cordycepin on MA-10 mouse Leydig tumor cells. Results showed that cordycepin significantly stimulated progesterone production in dose- and time-dependent manners. Adenosine receptor (AR subtype agonists were further used to treat MA-10 cells, showing that A1, A 2A , A 2B , and A3, AR agonists could stimulate progesterone production. However, StAR promoter activity and protein expression remained of no difference among all cordycepin treatments, suggesting that cordycepin might activate AR, but not stimulated StAR protein to regulate MA-10 cell steroidogenesis. Meanwhile, cordycepin could also induce apoptotic cell death in MA-10 cells. Moreover, four AR subtype agonists induced cell death in a dose-dependent manner, and four AR subtype antagonists could all rescue cell death under cordycepin treatment in MA-10 cells. In conclusion, cordycepin could activate adenosine subtype receptors and simultaneously induce steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells.

  2. Battery cell module

    Energy Technology Data Exchange (ETDEWEB)

    Shambaugh, J.S.

    1981-11-23

    A modular lithium battery having a plurality of cells, having electrical connecting means connecting the cells to output terminals, and venting means for releasing discharge byproducts to a chemical scrubber is disclosed. Stainless steel cell casings are potted in an aluminum modular case with syntactic foam and epoxy. The wall thickness resulting is about 0.5 inches.

  3. Aneuploidy in stem cells

    NARCIS (Netherlands)

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to real

  4. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  5. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission

    Directory of Open Access Journals (Sweden)

    Christine Gross

    2016-03-01

    Full Text Available The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1, a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4+ T-cells, and to a lesser extent, CD8+ T-cells, dendritic cells, and monocytes. Efficient infection of CD4+ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1 polarized budding of HTLV-1 into synaptic clefts; and (2 cell surface transfer of viral biofilms at virological synapses. In contrast to CD4+ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation.

  6. When size matters: differences in demineralized bone matrix particles affect collagen structure, mesenchymal stem cell behavior, and osteogenic potential.

    Science.gov (United States)

    Dozza, B; Lesci, I G; Duchi, S; Della Bella, E; Martini, L; Salamanna, F; Falconi, M; Cinotti, S; Fini, M; Lucarelli, E; Donati, D

    2017-04-01

    Demineralized bone matrix (DBM) is a natural, collagen-based, osteoinductive biomaterial. Nevertheless, there are conflicting reports on the efficacy of this product. The purpose of this study was to evaluate whether DBM collagen structure is affected by particle size and can influence DBM cytocompatibility and osteoinductivity. Sheep cortical bone was ground and particles were divided in three fractions with different sizes, defined as large (L, 1-2 mm), medium (M, 0.5-1 mm), and small (S, structure, with DBM-M being altered but not as much as DBM-S. DBM-M displayed a preferable trend in almost all biological characteristics tested, although all DBM particles revealed an optimal cytocompatibility. Subcutaneous implantation of DBM particles into immunocompromised mice resulted in bone induction only for DBM-M. When sheep MSC were seeded onto particles before implantation, all DBM particles were able to induce new bone formation with the best incidence for DBM-M and DBM-S. In conclusion, the collagen alteration in DBM-M is likely the best condition to promote bone induction in vivo. Furthermore, the choice of 0.5-1 mm particles may enable to obtain more efficient and consistent results among different research groups in bone tissue-engineering applications. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 105A: 1019-1033, 2017.

  7. Fuel cell catalyst degradation

    DEFF Research Database (Denmark)

    Arenz, Matthias; Zana, Alessandro

    2016-01-01

    Fuel cells are an important piece in our quest for a sustainable energy supply. Although there are several different types of fuel cells, the by far most popular is the proton exchange membrane fuel cell (PEMFC). Among its many favorable properties are a short start up time and a high power density...... increasing focus. Activity of the catalyst is important, but stability is essential. In the presented perspective paper, we review recent efforts to investigate fuel cell catalysts ex-situ in electrochemical half-cell measurements. Due to the amount of different studies, this review has no intention to give...

  8. Mechanics rules cell biology

    Directory of Open Access Journals (Sweden)

    Wang James HC

    2010-07-01

    Full Text Available Abstract Cells in the musculoskeletal system are subjected to various mechanical forces in vivo. Years of research have shown that these mechanical forces, including tension and compression, greatly influence various cellular functions such as gene expression, cell proliferation and differentiation, and secretion of matrix proteins. Cells also use mechanotransduction mechanisms to convert mechanical signals into a cascade of cellular and molecular events. This mini-review provides an overview of cell mechanobiology to highlight the notion that mechanics, mainly in the form of mechanical forces, dictates cell behaviors in terms of both cellular mechanobiological responses and mechanotransduction.

  9. Transparent ultraviolet photovoltaic cells.

    Science.gov (United States)

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

  10. Dental pulp stem cells

    DEFF Research Database (Denmark)

    Ashri, N. Y.; Ajlan, S. A.; Aldahmash, Abdullah M.

    2015-01-01

    scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from...... an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors.......Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable...

  11. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  12. Internalization of NK cells into tumor cells requires ezrin and leads to programmed cell-in-cell death

    Institute of Scientific and Technical Information of China (English)

    Shan Wang; Zhen Guo; Peng Xia; Tingting Liu; Jufang Wang; Shan Li; Lihua Sun; Jianxin Lu; Qian Wen; Mingqian Zhou; Li Ma; Xia Ding; Xiaoning Wang; Xuebiao Yao

    2009-01-01

    Cytotoxic lymphocytes are key players in the orchestration of immune response and elimination of defective cells. We have previously reported that natural killer (NK) cells enter target tumor cells, leading to either target cell death or self-destruction within tumor cells. However, it has remained elusive as to the fate of NK cells after internaliza-tion and whether the heterotypic cell-in-cell process is different from that of the homotypic cell-in-cell event recently named entosis. Here, we show that NK cells undergo a cell-in-cell process with the ultimate fate of apoptosis within tumor cells and reveal that the internalization process requires the actin cytoskeletal regulator, ezrin. To visualize how NK cells enter into tumor cells, we carried out real-time dual color imaging analyses of NK cell internalization into tumor cells. Surprisingly, most NK cells commit to programmed cell death after their entry into tumor cells, which is distinctively different from entosis observed in the homotypic cell-in-cell process. The apoptotic cell death of the internalized NK cells was evident by activation of caspase 3 and DNA fragmentation. Furthermore, NK cell death after internalization is attenuated by the caspase inhibitor, Z-VAD-FMK, confirming apoptosis as the mode of NK cell death within tumor cells. To determine protein factors essential for the entry of NK cells into tumor cells, we car-ried out siRNA-based knockdown analysis and discovered a critical role of ezrin in NK cell internalization. Impor-tantly, PKA-mediated phosphorylation of ezrin promotes the NK cell internalization process. Our findings suggest a novel regulatory mechanism by which ezrin governs NK cell internalization into tumor cells.

  13. Islet cell development.

    Science.gov (United States)

    Rojas, Anabel; Khoo, Adrian; Tejedo, Juan R; Bedoya, Francisco J; Soria, Bernat; Martín, Franz

    2010-01-01

    Over the last years, there has been great success in driving stem cells toward insulin-expressing cells. However, the protocols developed to date have some limitations, such as low reliability and low insulin production. The most successful protocols used for generation of insulin-producing cells from stem cells mimic in vitro pancreatic organogenesis by directing the stem cells through stages that resemble several pancreatic developmental stages. Islet cell fate is coordinated by a complex network of inductive signals and regulatory transcription factors that, in a combinatorial way, determine pancreatic organ specification, differentiation, growth, and lineage. Together, these signals and factors direct the progression from multipotent progenitor cells to mature pancreatic cells. Later in development and adult life, several of these factors also contribute to maintain the differentiated phenotype of islet cells. A detailed understanding of the processes that operate in the pancreas during embryogenesis will help us to develop a suitable source of cells for diabetes therapy. In this chapter, we will discuss the main transcription factors involved in pancreas specification and beta-cell formation.

  14. Cell biology. Metabolic control of cell death.

    Science.gov (United States)

    Green, Douglas R; Galluzzi, Lorenzo; Kroemer, Guido

    2014-09-19

    Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries, including oxidative phosphorylation and transport of metabolites across membranes, may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of "metabolic checkpoints" that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss.

  15. 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 ...

  16. Enteroendocrine cell types revisited

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Egerod, Kristoffer Lihme; Lund, Mari L

    2013-01-01

    The GI-tract is profoundly involved in the control of metabolism through peptide hormones secreted from enteroendocrine cells scattered throughout the gut mucosa. A large number of recently generated transgenic reporter mice have allowed for direct characterization of biochemical and cell...... biological properties of these previously highly elusive enteroendocrine cells. In particular the surprisingly broad co-expression of six functionally related hormones in the intestinal enteroendocrine cells indicates that it should be possible to control not only the hormone secretion but also the type...... and number of enteroendocrine cells. However, this will require a more deep understanding of the factors controlling differentiation, gene expression and specification of the enteroendocrine cells during their weekly renewal from progenitor cells in the crypts of the mucosa....

  17. Cell Factory Engineering.

    Science.gov (United States)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-03-22

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta-review provides general strategy guides for the broad range of applications of rational engineering of cell factories.

  18. Peripheral giant cell granuloma

    Directory of Open Access Journals (Sweden)

    Padam Narayan Tandon

    2012-01-01

    Full Text Available Peripheral giant cell granuloma or the so-called "giant cell epulis" is the most common oral giant cell lesion. It normally presents as a soft tissue purplish-red nodule consisting of multinucleated giant cells in a background of mononuclear stromal cells and extravasated red blood cells. This lesion probably does not represent a true neoplasm, but rather may be reactive in nature, believed to be stimulated by local irritation or trauma, but the cause is not certainly known. This article reports a case of peripheral giant cell granuloma arising at the maxillary anterior region in a 22-year-old female patient. The lesion was completely excised to the periosteum level and there is no residual or recurrent swelling or bony defect apparent in the area of biopsy after a follow-up period of 6 months.

  19. Cell viability assays: introduction.

    Science.gov (United States)

    Stoddart, Martin J

    2011-01-01

    The measurement of cell viability plays a fundamental role in all forms of cell culture. Sometimes it is the main purpose of the experiment, such as in toxicity assays. Alternatively, cell viability can be used to -correlate cell behaviour to cell number, providing a more accurate picture of, for example, anabolic -activity. There are wide arrays of cell viability methods which range from the most routine trypan blue dye exclusion assay to highly complex analysis of individual cells, such as using RAMAN microscopy. The cost, speed, and complexity of equipment required will all play a role in determining the assay used. This chapter aims to provide an overview of many of the assays available today.

  20. Involvement of plant stem cells or stem cell-like cells in dedifferentiation

    Directory of Open Access Journals (Sweden)

    Fangwei eJiang

    2015-11-01

    Full Text Available Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation.

  1. Stages of Renal Cell Cancer

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  2. Cutaneous hamartoma with pagetoid cells.

    Science.gov (United States)

    Piérard-Franchimont, C; Dosal, F L; Estrada, J A; Piérard, G E

    1991-04-01

    We report an unusual cutaneous hamartoma with pagetoid cells characterized by the presence of intraepidermal cells resembling Toker's cells of the nipple. These cells were EMA positive and could be related to the histogenesis of some Paget's disease.

  3. Sickle Cell Disease (For Parents)

    Science.gov (United States)

    ... Old Feeding Your 1- to 2-Year-Old Sickle Cell Disease KidsHealth > For Parents > Sickle Cell Disease Print ... healthy, and productive lives. A Closer Look at Sickle Cell Disease The different types of sickle cell disease ...

  4. Membrane Cells for Brine Electrolysis.

    Science.gov (United States)

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  5. High Red Blood Cell Count

    Science.gov (United States)

    Symptoms High red blood cell count By Mayo Clinic Staff A high red blood cell count is an increase in oxygen-carrying cells in your bloodstream. Red blood cells transport oxygen from your lungs to tissues throughout ...

  6. PEROVSKITE SOLAR CELLS (REVIEW ARTICLE)

    OpenAIRE

    Benli, Deniz Ahmet

    2015-01-01

    A solar cell is a device that converts sunlight into electricity. There are different types of solar cells but this report mainly focuses on a type of new generation solar cell that has the name organo-metal halide perovskite, shortly perovskite solar cells. In this respect, the efficiency of power conversion is taken into account to replace the dominancy of traditional and second generation solar cell fields by perovskite solar cells. Perovskite solar cell is a type of solar cell including a...

  7. Cell to substratum and cell to cell interactions of microalgae.

    Science.gov (United States)

    Ozkan, Altan; Berberoglu, Halil

    2013-12-01

    This paper reports the cell to substratum and cell to cell interactions of a diverse group of microalgae based on the Extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) approach using the previously reported physico-chemical surface properties. The microalgae included 10 different species of green algae and diatoms from both freshwater and saltwater environments while the substrata included glass, indium-tin oxide (ITO), stainless steel, polycarbonate, polyethylene, and polystryrene. The results indicated that acid-base interactions were the dominating mechanism of interaction for microalgae. For green algae, if at least one of the interacting surfaces was hydrophobic, adhesion at primary minimum was predicted without any energy barrier. However, most diatom systems featured energy barriers for adhesion due to repulsive van der Waals interactions. The results reported in this study are expected to provide useful data and insight into the interaction mechanisms of microalgae cells with each other and with substrata for a number of practical applications including prevention of biofouling of photobioreactors and other man-made surfaces, promotion of biofilm formation in algal biofilm photobioreactors, and developing bioflocculation strategies for energy efficient harvesting of algal biomass. Particularly, Botryococcus braunii and Cerithiopsis fusiformis were identified as promising species for biofloccuation and biofilm formation in freshwater and saltwater aquatic systems, respectively. Finally, based on the observed trends in this study, use of hydrophilic algae and hydrophilic coatings over surfaces are recommended for minimizing biofouling in aquatic systems.

  8. Biology of Schwann cells.

    Science.gov (United States)

    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D

    2013-01-01

    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate.

  9. Embryonic stem cell-somatic cell fusion and postfusion enucleation.

    Science.gov (United States)

    Sumer, Huseyin; Verma, Paul J

    2015-01-01

    Embryonic stem (ES) cells are able to reprogram somatic cells following cell fusion. The resulting cell hybrids have been shown to have similar properties to pluripotent cells. It has also been shown that transcriptional changes can occur in a heterokaryon, without nuclear hybridization. However it is unclear whether these changes can be sustained following removal of the dominant ES nucleus. In this chapter, methods are described for the cell fusion of mouse tetraploid ES cells with somatic cells and enrichment of the resulting heterokaryons. We next describe the conditions for the differential removal of the ES cell nucleus, allowing for the recovery of somatic cells.

  10. Isolation of rare cancer cells from blood cells using dielectrophoresis.

    Science.gov (United States)

    Salmanzadeh, Alireza; Sano, Michael B; Shafiee, Hadi; Stremler, Mark A; Davalos, Rafael V

    2012-01-01

    In this study, we investigate the application of contactless dielectrophoresis (cDEP) for isolating cancer cells from blood cells. Devices with throughput of 0.2 mL/hr (equivalent to sorting 3×10(6) cells per minute) were used to trap breast cancer cells while allowing blood cells through. We have shown that this technique is able to isolate cancer cells in concentration as low as 1 cancer cell per 10(6) hematologic cells (equivalent to 1000 cancer cells in 1 mL of blood). We achieved 96% trapping of the cancer cells at 600 kHz and 300 V(RMS).

  11. Cell-Substrate Adhesion by Amoeboid Cells

    Science.gov (United States)

    Flanders, Bret; Panta, Krishna

    Amoeboid migration is a rapid (10 μm min-1) mode of migration that some tumor cells exhibit. To permit such rapid movement, the adhesive contacts between the cell and the substrate must be relatively short-lived and weak. In this study, we investigate the basic adhesive character of amoeboid cells (D. discoideum) in contact with silanized glass substrates. We observe the initiation and spreading of the adhesive contacts that these cells establish as they settle under gravity onto the substrate and relax towards mechanical equilibrium. The use of interference reflection microscopy and cellular tethering measurements have allowed us to determine the basic adhesive properties of the cell: the membrane-medium interfacial energy; the bending modulus; the equilibrium contact angle; and the work of adhesion. We find the time scale on which settling occurs to be longer than expected. Implications of these results on adhesion and migration will be discussed. The authors are grateful for support from NSF (CBET-1451903) and NIH (1R21EY026392).

  12. Aneuploidy in stem cells

    Institute of Scientific and Technical Information of China (English)

    Jorge; Garcia-Martinez; Bjorn; Bakker; Klaske; M; Schukken; Judith; E; Simon; Floris; Foijer

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells(IPSCs) from somatic cells has brought this promise steps closer to reality. However,as somatic cells might have accumulated various chromosomal abnormalities,including aneuploidies throughout their lives,the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated,or worse,become at risk of adopting a malignant fate. In this review,we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore,we review the differences between how somatic cells and stem cells respond to aneuploidy.

  13. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  14. Cell Factory Engineering

    DEFF Research Database (Denmark)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-01-01

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely...... focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies...... in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta...

  15. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells...... independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment...... to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine...

  16. Fish germ cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fish, like many other animals, have two major cell lineages, namely the germline and soma. The germ-soma separation is one of the earliest events of embryonic development. Germ cells can be specifically labeled and isolated for culture and transplan-tation, providing tools for reproduction of endangered species in close relatives, such as surrogate production of trout in salmon. Haploid cell cultures, such as medaka haploid embryonic stem cells have recently been obtained, which are capable of mimicking sperm to produce fertile offspring, upon nuclear being directly transferred into normal eggs. Such fish originated from a mosaic oocyte that had a haploid meiotic nucleus and a transplanted haploid mitotic cell culture nucleus. The first semi-cloned fish is Holly. Here we review the current status and future directions of understanding and manipulating fish germ cells in basic research and reproductive technology.

  17. Trafficking and cell migration.

    Science.gov (United States)

    Ulrich, Florian; Heisenberg, Carl-Philipp

    2009-07-01

    The migration of single cells and epithelial sheets is of great importance for gastrulation and organ formation in developing embryos and, if misregulated, can have dire consequences e.g. during cancer metastasis. A keystone of cell migration is the regulation of adhesive contacts, which are dynamically assembled and disassembled via endocytosis. Here, we discuss some of the basic concepts about the function of endocytic trafficking during cell migration: transport of integrins from the cell rear to the leading edge in fibroblasts; confinement of signalling to the front of single cells by endocytic transport of growth factors; regulation of movement coherence in multicellular sheets by cadherin turnover; and shaping of extracellular chemokine gradients. Taken together, endocytosis enables migrating cells and tissues to dynamically modulate their adhesion and signalling, allowing them to efficiently migrate through their extracellular environment.

  18. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Amitkumar B Pandav

    2012-01-01

    Full Text Available Plasma cell granuloma, also known as inflammatory pseudotumor is a tumor-like lesion that manifests primarily in the lungs. But it may occur in various other anatomic locations like orbit, head and neck, liver and rarely in the oral cavity. We here report an exceedingly rare case of gingival plasma cell granuloma in a 58 year old woman who presented with upper gingival polypoidal growth. The histopathological examination revealed a mass composed of proliferation of benign spindle mesenchymal cells in a loose myxoid and fibrocollagenous stroma along with dense infiltrate of chronic inflammatory cells predominantly containing plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma.

  19. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Phadnaik Mangesh

    2010-01-01

    Full Text Available Plasma cell granuloma is a rare reactive lesion composed of polyclonal plasma cells. It manifests primarily in the lungs, but may occur in various other anatomic locations like the oral cavity. Intraoral plasma cell granulomas involving the tongue, lip, oral mucosa and gingiva have been reported in the past. This case presents a 54-year-old female with chronic periodontitis and mandibular anterior gingival overgrowth treated by Phase I therapy (scaling and root planing and excisional biopsy. Histological examination revealed inflammatory cell infiltrate containing sheets of plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma. This case highlights the need to biopsy for unusual lesions to rule out potential neoplasms.

  20. Induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Siddhartha Bhowmik; LI Yong

    2011-01-01

    Induced pluripotent stem (iPS) cells are a recent development which has brought a promise of great therapeutic values. The previous technique of somatic cell nuclear transfer (SCNT) has been ineffective in humans. Recent discoveries show that human fibroblasts can be reprogrammed by a transient over expression of a small number of genes; they can undergo induced pluripotency. iPS were first produced in 2006. By 2008, work was underway to remove the potential oncogenes from their structure. In 2009, protein iPS (piPS) cells were discovered. Surface markers and reporter genes play an important role in stem cell research. Clinical applications include generation of self renewing stem cells, tissue replacement and many more. Stem cell therapy has the ability to dramatically change the treatment of human diseases.

  1. Myoepithelial cells in pathology.

    Science.gov (United States)

    Balachander, N; Masthan, K M K; Babu, N Aravindha; Anbazhagan, V

    2015-04-01

    Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  2. Myoepithelial cells in pathology

    Directory of Open Access Journals (Sweden)

    N Balachander

    2015-01-01

    Full Text Available Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  3. Cytoskeleton and Cell Motility

    CERN Document Server

    Risler, Thomas

    2011-01-01

    The present article is an invited contribution to the Encyclopedia of Complexity and System Science, Robert A. Meyers Ed., Springer New York (2009). It is a review of the biophysical mechanisms that underly cell motility. It mainly focuses on the eukaryotic cytoskeleton and cell-motility mechanisms. Bacterial motility as well as the composition of the prokaryotic cytoskeleton is only briefly mentioned. The article is organized as follows. In Section III, I first present an overview of the diversity of cellular motility mechanisms, which might at first glance be categorized into two different types of behaviors, namely "swimming" and "crawling". Intracellular transport, mitosis - or cell division - as well as other extensions of cell motility that rely on the same essential machinery are briefly sketched. In Section IV, I introduce the molecular machinery that underlies cell motility - the cytoskeleton - as well as its interactions with the external environment of the cell and its main regulatory pathways. Sec...

  4. Mammary gland stem cells

    DEFF Research Database (Denmark)

    Fridriksdottir, Agla J R; Petersen, Ole W; Rønnov-Jessen, Lone

    2011-01-01

    Distinct subsets of cells, including cells with stem cell-like properties, have been proposed to exist in normal human breast epithelium and breast carcinomas. The cellular origins of epithelial cells contributing to gland development, tissue homeostasis and cancer are, however, still poorly...... and differences between mouse and human gland development with particular emphasis on the identity and localization of stem cells, and the influence of the surrounding microenvironment. It is concluded that while recent advances in the field have contributed immense insight into how the normal mammary gland...... develops and is maintained, significant discrepancies exist between the mouse and human gland which should be taken into consideration in current and future models of mammary stem cell biology....

  5. Differentiated human stem cells resemble fetal, not adult, β cells.

    Science.gov (United States)

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  6. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  7. Lymphomas of large cells.

    Science.gov (United States)

    Staples, W G; Gétaz, E P

    1977-09-03

    Historial aspects of the classification of large-cell lymphomas are described. Immunological characterization of the lymphomas has been made possible by identification of T and B lymphocytes according to their cell membrane surface characteristics. The pathogenesis of lymphomas has been clarified by the germinal (follicular) centre cell concepts of Lennert and Lukes and Collins. The various classifications are presented and compared. Whether these subdivisions will have any relevance in the clinical context remains to be seen.

  8. Immobilized Cell Research

    Science.gov (United States)

    1990-10-31

    beads, the plasmid is twice as stable as in cells In a process where immobilized cells produce material grown in continuous culture over 200...carrageenan) or chemically cross-linked, or- Penicillium chrysogenum than in washed freely suspended ganic polymer (Ca-alginate, polyacrylamide, and mycelium ...these materials are formed into the freely suspended cells stopped after 6 days. If the beads of several millimeters in diameter by allowing the

  9. Cell Wall Proteome

    OpenAIRE

    Boudart, Georges; Minic, Zoran; Albenne, Cécile; Canut, Hervé; Jamet, Elisabeth; Pont-Lezica, Rafael F

    2007-01-01

    In this chapter, we will focus on the contribution of proteomics to the identification and determination of the structure and function of CWPs as well as discussing new perspectives in this area. The great variety of proteins found in the plant cell wall is described. Some families, such as glycoside hydrolases, proteases, lectins, and inhibitors of cell wall modifying enzymes, are discussed in detail. Examples of the use of proteomic techniques to elucidate the structure of various cell wall...

  10. Systems cell biology.

    Science.gov (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D

    2014-09-15

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  11. Origins of pluripotent stem cells.

    Science.gov (United States)

    Roelen, B A J; Chuva De Sousa Lopes, S M

    2011-08-01

    Different types of pluripotent stem cells can be identified and cultured in vitro. Here an overview is presented of the various pluripotent stem cells types. Embryonal carcinoma (EC) cells that have been cultured in vitro provided the groundwork for future pluripotent cell cultures. Conditions established for these cells such as culture on a feeder layer of mouse embryonic fibroblasts and the importance of fetal calf serum were initially also used for the culture of mouse embryonic stem (ES) cells derived from the inner cell masses of blastocysts. Embryonic stem cells derived from human blastocysts were found to require different conditions and are cultured in the presence of activin and basic fibroblast growth factor. Recently pluripotent stem cells have also been derived from mouse peri-implantation epiblasts. Since these epiblast stem cells (EpiSCs) require the same conditions as the human ES cells it has been suggested that human ES cells are more similar to mouse EpiSCs than to mouse ES cells. Pluripotent cell lines have also been derived from migratory primordial germ cells and spermatogonial stem cells. The creation of pluripotent stem cells from adult cells by the introduction of reprogramming transcription factors, so-called induced pluripotent stem (iPS) cells allowed the derivation of patient-specific pluripotent stem cells without the need of creation of a human blastocyst after cloning by somatic cells nuclear transfer. Recently it has become clear however that iPS cells may be quite different to ES cells in terms of epigenetics.

  12. Beta cell dynamics: beta cell replenishment, beta cell compensation and diabetes.

    Science.gov (United States)

    Cerf, Marlon E

    2013-10-01

    Type 2 diabetes, characterized by persistent hyperglycemia, arises mostly from beta cell dysfunction and insulin resistance and remains a highly complex metabolic disease due to various stages in its pathogenesis. Glucose homeostasis is primarily regulated by insulin secretion from the beta cells in response to prevailing glycemia. Beta cell populations are dynamic as they respond to fluctuating insulin demand. Beta cell replenishment and death primarily regulate beta cell populations. Beta cells, pancreatic cells, and extra-pancreatic cells represent the three tiers for replenishing beta cells. In rodents, beta cell self-replenishment appears to be the dominant source for new beta cells supported by pancreatic cells (non-beta islet cells, acinar cells, and duct cells) and extra-pancreatic cells (liver, neural, and stem/progenitor cells). In humans, beta cell neogenesis from non-beta cells appears to be the dominant source of beta cell replenishment as limited beta cell self-replenishment occurs particularly in adulthood. Metabolic states of increased insulin demand trigger increased insulin synthesis and secretion from beta cells. Beta cells, therefore, adapt to support their physiology. Maintaining physiological beta cell populations is a strategy for targeting metabolic states of persistently increased insulin demand as in diabetes.

  13. Rapid cooled lens cell

    Science.gov (United States)

    Stubbs, David M.; Hsu, Ike C.

    1991-12-01

    This paper describes the optomechanical design, thermal analysis, fabrication, and test evaluation processes followed in developing a rapid cooled, infrared lens cell. Thermal analysis was the key engineering discipline exercised in the design phase. The effect of thermal stress on the lens, induced by rapid cooling of the lens cell, was investigated. Features of this lens cell that minimized the thermal stress will be discussed in a dedicated section. The results of thermal analysis on the selected lens cell design and the selection of the flow channel design in the heat exchanger will be discussed. Throughout the paper engineering drawings, illustrations, analytical results, and photographs of actual hardware are presented.

  14. Cell sorting in development.

    Science.gov (United States)

    Krens, S F Gabby; Heisenberg, Carl-Philipp

    2011-01-01

    During the development of multicellular organisms, cell fate specification is followed by the sorting of different cell types into distinct domains from where the different tissues and organs are formed. Cell sorting involves both the segregation of a mixed population of cells with different fates and properties into distinct domains, and the active maintenance of their segregated state. Because of its biological importance and apparent resemblance to fluid segregation in physics, cell sorting was extensively studied by both biologists and physicists over the last decades. Different theories were developed that try to explain cell sorting on the basis of the physical properties of the constituent cells. However, only recently the molecular and cellular mechanisms that control the physical properties driving cell sorting, have begun to be unraveled. In this review, we will provide an overview of different cell-sorting processes in development and discuss how these processes can be explained by the different sorting theories, and how these theories in turn can be connected to the molecular and cellular mechanisms driving these processes.

  15. Red cell enzymes.

    Science.gov (United States)

    Paniker, N V

    1975-03-01

    As compared to other cells of the body, the mammalian red cell has one of the simplest structural organizations. As a result, this cell has been extensively used in studies involving the structure, function, and integrity of cell membranes as well as cytoplasmic events. Additionally, the metabolic activities of the red blood cell are also relatively simple. During the past quarter century or so, an ocean of knowledge has been gathered on various aspects of red cell metabolism and function. The fields of enzymes, hemoglobin, membrane, and metabolic products comprise the major portion of this knowledge. These advances have made valuable contributions to biochemistry and medicine. Despite these favorable aspects of this simple, anucleated cell, it must be conceded that our knowledge about the red cell is far from complete. We are still in the dark concerning the mechanism involved in several aspects of its membrane, hemoglobin, enzymes, and a large number of other constituents. For example, a large number of enzymes with known catalytic activity but with unknown function have eluded investigators despite active pursuit. This review will be a consolidation of our present knowledge of human red cell enzymes, with particular reference to their usefulness in the diagnosis and therapy of disease. Owing to the multitude of publications by prominent investigators on each of the approximately 50 enzymes discussed in this review, it was impossible to cite a majority of them.

  16. Littoral Cells 2005

    Data.gov (United States)

    California Department of Resources — Littoral cells along the California Coast. Originally digitized by Melanie Coyne from the Assessment and Atlas of Shoreline Erosion Along the California Coast...

  17. [Endothelial cell adhesion molecules].

    Science.gov (United States)

    Ivanov, A N; Norkin, I A; Puchin'ian, D M; Shirokov, V Iu; Zhdanova, O Iu

    2014-01-01

    The review presents current data concerning the functional role of endothelial cell adhesion molecules belonging to different structural families: integrins, selectins, cadherins, and the immunoglobulin super-family. In this manuscript the regulatory mechanisms and factors of adhesion molecules expression and distribution on the surface of endothelial cells are discussed. The data presented reveal the importance of adhesion molecules in the regulation of structural and functional state of endothelial cells in normal conditions and in pathology. Particular attention is paid to the importance of these molecules in the processes of physiological and pathological angiogenesis, regulation of permeability of the endothelial barrier and cell transmigration.

  18. Analysing immune cell migration.

    Science.gov (United States)

    Beltman, Joost B; Marée, Athanasius F M; de Boer, Rob J

    2009-11-01

    The visualization of the dynamic behaviour of and interactions between immune cells using time-lapse video microscopy has an important role in modern immunology. To draw robust conclusions, quantification of such cell migration is required. However, imaging experiments are associated with various artefacts that can affect the estimated positions of the immune cells under analysis, which form the basis of any subsequent analysis. Here, we describe potential artefacts that could affect the interpretation of data sets on immune cell migration. We propose how these errors can be recognized and corrected, and suggest ways to prevent the data analysis itself leading to biased results.

  19. Microencapsulation Of Living Cells

    Science.gov (United States)

    Chang, Manchium; Kendall, James M.; Wang, Taylor G.

    1989-01-01

    In experimental technique, living cells and other biological materials encapsulated within submillimeter-diameter liquid-filled spheres. Sphere material biocompatible, tough, and compliant. Semipermeable, permitting relatively small molecules to move into and out of sphere core but preventing passage of large molecules. New technique promises to make such spherical capsules at high rates and in uniform, controllable sizes. Capsules injected into patient through ordinary hypodermic needle. Promising application for technique in treatment of diabetes. Also used to encapsulate pituitary cells and thyroid hormone adrenocortical cells for treatment of other hormonal disorders, to encapsulate other secreting cells for transplantation, and to package variety of pharmaceutical products and agricultural chemicals for controlled release.

  20. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  1. Assessment of cell viability.

    Science.gov (United States)

    Johnson, Simon; Nguyen, Vy; Coder, David

    2013-01-01

    Cell viability may be judged by morphological changes or by changes in membrane permeability and/or physiological state inferred from the exclusion of certain dyes or the uptake and retention of others. This unit presents methods based on dye exclusion, esterase activity, and mitochondrial membrane potential, as well as protocols for determining the pre-fixation viability of fixed cells either before or after fixation with amine-reactive dyes suitable for a range of excitation wavelengths. Membrane-impermeable dead cell and live cell dyes as well as dye-exclusion procedures for microscopy are also included.

  2. Dedifferentiated adipocyte-derived progeny cells (DFAT cells)

    OpenAIRE

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J.; Rasmussen, Theodore P; Bergen, Werner G.; Dodson, Michael V.

    2013-01-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, ...

  3. A focus on parietal cells as a renewing cell population

    Institute of Scientific and Technical Information of China (English)

    Sherif; M; Karam

    2010-01-01

    The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells...

  4. Preparation and characterization of novel antibacterial castor oil-based polyurethane membranes for wound dressing application.

    Science.gov (United States)

    Yari, Abbas; Yeganeh, Hamid; Bakhshi, Hadi; Gharibi, Reza

    2014-01-01

    Preparation of novel antibacterial and cytocompatible polyurethane membranes as occlusive dressing, which can provide moist and sterile environment over mild exudative wounds is considered in this work. In this regard, an epoxy-terminated polyurethane (EPU) prepolymer based on castor oil and glycidyltriethylammonium chloride (GTEAC) as a reactive bactericidal agent were synthesized. Polyurethane membranes were prepared through cocuring of EPU and different content of GTEAC with 1,4-butane diamine. The physical and mechanical properties, as well as cytocompatibility and antibacterial performance of prepared membranes were studied. Depending on their chemical formulations, the equilibrium water absorption and water vapor transmission rate values of the membranes were in ranges of 3-85% and 53-154g m(-2) day(-1), respectively. Therefore, these transparent membranes can maintain for a long period the moist environment over the wounds with low exudates. Detailed cytotoxicity analysis of samples against mouse L929 fibroblast and MCA-3D keratinocyte cells showed good level of cytocompatibility of membranes after purification via extraction of residual unreacted GTEAC moieties. The antibacterial activity of the membranes against Escherichia coli and Staphylococcus aureus bacteria was also studied. The membrane containing 50% GTEAC exhibited an effective antibacterial activity, while showed acceptable cytocompatibility and therefore, can be applied as an antibacterial occlusive wound dressing.

  5. Regulation of B Cell to Plasma Cell Transition within the Follicular B Cell Response.

    Science.gov (United States)

    Nera, K-P; Kyläniemi, M K; Lassila, O

    2015-09-01

    Persistent humoral immunity depends on the follicular B cell response and on the generation of somatically mutated high-affinity plasma cells and memory B cells. Upon activation by an antigen, cognately activated follicular B cells and follicular T helper (TFH ) cells initiate germinal centre (GC) reaction during which high-affinity effector cells are generated. The differentiation of activated follicular B cells into plasma cells and memory B cells is guided by complex selection events, both at the cellular and molecular level. The transition of B cell into a plasma cell during the GC response involves alterations in the microenvironment and developmental state of the cell, which are guided by cell-extrinsic signals. The developmental cell fate decisions in response to these signals are coordinated by cell-intrinsic gene regulatory network functioning at epigenetic, transcriptional and post-transcriptional levels.

  6. Eficiência de absorção, transporte e utilização de macronutrientes por porta-enxertos de caramboleira, cultivados em soluções nutritivas Up take, transportat and use of macronutrients in rootstock for star fruit tree cultivated in nutrient solutions

    Directory of Open Access Journals (Sweden)

    Danilo Eduardo Rozane

    2007-08-01

    Full Text Available O estado nutricional de plantas cultivadas em solução nutritiva pode ser influenciado pelo tipo de solução utilizada, afetando desta forma seu adequado crescimento. Com este trabalho, objetivou-se avaliar a exigência nutricional de porta-enxertos de caramboleira, cultivados em quatro diferentes soluções nutritivas. O delineamento experimental empregado foi inteiramente casualizado, com três repetições, tendo como tratamentos as quatro soluções. Como solução padrão foi utilizada a de Hoagland & Arnon, comparada à outras três soluções. O experimento foi conduzido em condições de casa-de-vegetação, em recipientes plásticos com 8 L de capacidade. Após 150 dias do transplantio, foram determinados a matéria seca e o teor de nutrientes, inferindo-se o conteúdo dos macronutrientes na planta. Com esses resultados calculou-se os índices: eficiência de absorção; eficiência de transporte e eficiência de utilização dos nutrientes. As soluções nutritivas de Sarruge, de Castellane & Araújo e de Furlani foram semelhantes na produção de matéria seca das plantas de caramboleira. O uso da solução nutritiva de Hoagland & Arnon resultou em menor produção de matéria seca das caramboleiras, e, também, menor eficiência de utilização de Ca e Mg pelas plantas. A eficiência de transporte dos nutrientes foi a mais afetada pelas soluções nutritivas utilizadas, enquanto a eficiência de utilização dos nutrientes sofreu pouca variação em função das soluções empregadas.The nutritional status of plants cultivated in nutrient solutions way be influenced by the solution which would affect its growth plants. The present essay was undergone to assess the nutritional demands of root stock for star fruit trees, cultivated in four different nutritional solutions. An completely experimental design was used with three repetitions, with four different nutrient solutions as treatments. The Hoagland & Arnon solution was used as standard and was the control wich was with compared three other solutions. The experiment was carrie out under green house conditions, using 8 L pot. After 150 days of transplantation, dry material and macro nutrient levels were determined. The following indicators were calculated: absorption efficiency; transportation efficiency, and efficiency of nutrient use. The Sarruge, the Castellane & Araújo, and the Furlani nutrient solutions were similar to accumulation of dry material in the star fruit plants. The use of the Hoagland & Arnon solution resulted in lower material dry production in and also lower of Ca and Mg use. Nutrient transportation efficiency was the indicator most affected by the different nutritional solutions used, while efficiency of nutrient use showed small variation when comparing the solutions.

  7. Eficiência de absorção, transporte e utilização de macronutrientes por porta-enxertos de caramboleira, cultivados em soluções nutritivas Up take, transportat and use of macronutrients in rootstock for star fruit tree cultivated in nutrient solutions

    OpenAIRE

    Danilo Eduardo Rozane; Renato de Mello Prado; Claudenir Facincani Franco; William Natale

    2007-01-01

    O estado nutricional de plantas cultivadas em solução nutritiva pode ser influenciado pelo tipo de solução utilizada, afetando desta forma seu adequado crescimento. Com este trabalho, objetivou-se avaliar a exigência nutricional de porta-enxertos de caramboleira, cultivados em quatro diferentes soluções nutritivas. O delineamento experimental empregado foi inteiramente casualizado, com três repetições, tendo como tratamentos as quatro soluções. Como solução padrão foi utilizada a de Hoagland ...

  8. The Research on the Building of the Service System for Business Economics Higher Vocational College Students’ Business Start - ups--- Taking Guangxi International Business Vocational College as An Example%商务经济类高职学生创业服务体系建设研究--以广西国际商务职业技术学院为例

    Institute of Scientific and Technical Information of China (English)

    谭小燕

    2013-01-01

      以创业带动就业是教育部出台解决高校大学生就业的一个途径,商务经济类高职院校培养商务人才、扶持大学生创业应是学校特色,更是响应国家号召。本文以广西国际商务职业技术学院为例,阐述了学院如何构建学校、政府、社会三位一体的创业教育、创业扶持、创业氛围服务体系,培养大量创业型商务人才,成功扶持大学生创业,带动了就业。%The policy ,offered by the Ministry of Education ,to encourage business students start - ups is one of the measures to improve the employment of college students. Responding to this call ,the business economics higher vocational colleges should take priority in the features’setting of fostering business professionals and supporting business start - ups.In order to cultivate large amount of entrepreneurial business professionals ,this article ,taking Guangxi International Business Vocational College as an example ,described how to build the trinity of service system by joint effort of colleges ,governments and society for entrepre‐neurial education ,support and environment ,which has successfully assisted students’ business start - ups and stimulated the employment.

  9. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  10. Single-cell sequencing in stem cell biology.

    Science.gov (United States)

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  11. Wnt-Dependent Control of Cell Polarity in Cultured Cells.