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Sample records for cells generate multiple

  1. Multiple-exciton generation in lead selenide nanorod solar cells with external quantum efficiencies exceeding 120.

    Science.gov (United States)

    Davis, Nathaniel J L K; Böhm, Marcus L; Tabachnyk, Maxim; Wisnivesky-Rocca-Rivarola, Florencia; Jellicoe, Tom C; Ducati, Caterina; Ehrler, Bruno; Greenham, Neil C

    2015-09-28

    Multiple-exciton generation-a process in which multiple charge-carrier pairs are generated from a single optical excitation-is a promising way to improve the photocurrent in photovoltaic devices and offers the potential to break the Shockley-Queisser limit. One-dimensional nanostructures, for example nanorods, have been shown spectroscopically to display increased multiple exciton generation efficiencies compared with their zero-dimensional analogues. Here we present solar cells fabricated from PbSe nanorods of three different bandgaps. All three devices showed external quantum efficiencies exceeding 100% and we report a maximum external quantum efficiency of 122% for cells consisting of the smallest bandgap nanorods. We estimate internal quantum efficiencies to exceed 150% at relatively low energies compared with other multiple exciton generation systems, and this demonstrates the potential for substantial improvements in device performance due to multiple exciton generation.

  2. Multiple-exciton generation in lead selenide nanorod solar cells with external quantum efficiencies exceeding 120%

    Science.gov (United States)

    Davis, Nathaniel J. L. K.; Böhm, Marcus L.; Tabachnyk, Maxim; Wisnivesky-Rocca-Rivarola, Florencia; Jellicoe, Tom C.; Ducati, Caterina; Ehrler, Bruno; Greenham, Neil C.

    2015-01-01

    Multiple-exciton generation—a process in which multiple charge-carrier pairs are generated from a single optical excitation—is a promising way to improve the photocurrent in photovoltaic devices and offers the potential to break the Shockley–Queisser limit. One-dimensional nanostructures, for example nanorods, have been shown spectroscopically to display increased multiple exciton generation efficiencies compared with their zero-dimensional analogues. Here we present solar cells fabricated from PbSe nanorods of three different bandgaps. All three devices showed external quantum efficiencies exceeding 100% and we report a maximum external quantum efficiency of 122% for cells consisting of the smallest bandgap nanorods. We estimate internal quantum efficiencies to exceed 150% at relatively low energies compared with other multiple exciton generation systems, and this demonstrates the potential for substantial improvements in device performance due to multiple exciton generation. PMID:26411283

  3. A developmentally plastic adult mouse kidney cell line spontaneously generates multiple adult kidney structures

    Energy Technology Data Exchange (ETDEWEB)

    Webb, Carol F., E-mail: carol-webb@omrf.org [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Ratliff, Michelle L., E-mail: michelle-ratliff@omrf.org [Immunobiology and Cancer Research, Oklahoma Medical Research Foundation, Oklahoma City, OK (United States); Powell, Rebecca, E-mail: rebeccapowell@gmail.com [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Wirsig-Wiechmann, Celeste R., E-mail: celeste-wirsig@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Lakiza, Olga, E-mail: olga-lakiza@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States); Obara, Tomoko, E-mail: tomoko-obara@ouhsc.edu [Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK (United States)

    2015-08-07

    Despite exciting new possibilities for regenerative therapy posed by the ability to induce pluripotent stem cells, recapitulation of three-dimensional kidneys for repair or replacement has not been possible. ARID3a-deficient mouse tissues generated multipotent, developmentally plastic cells. Therefore, we assessed the adult mouse ARID3a−/− kidney cell line, KKPS5, which expresses renal progenitor surface markers as an alternative cell source for modeling kidney development. Remarkably, these cells spontaneously developed into multicellular nephron-like structures in vitro, and engrafted into immunocompromised medaka mesonephros, where they formed mouse nephron structures. These data implicate KKPS5 cells as a new model system for studying kidney development. - Highlights: • An ARID3a-deficient mouse kidney cell line expresses multiple progenitor markers. • This cell line spontaneously forms multiple nephron-like structures in vitro. • This cell line formed mouse kidney structures in immunocompromised medaka fish kidneys. • Our data identify a novel model system for studying kidney development.

  4. Efficient Generation of Myelinating Oligodendrocytes from Primary Progressive Multiple Sclerosis Patients by Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Panagiotis Douvaras

    2014-08-01

    Full Text Available Multiple sclerosis (MS is a chronic demyelinating disease of unknown etiology that affects the CNS. While current therapies are primarily directed against the immune system, the new challenge is to address progressive MS with remyelinating and neuroprotective strategies. Here, we develop a highly reproducible protocol to efficiently derive oligodendrocyte progenitor cells (OPCs and mature oligodendrocytes from induced pluripotent stem cells (iPSCs. Key elements of our protocol include adherent cultures, dual SMAD inhibition, and addition of retinoids from the beginning of differentiation, which lead to increased yields of OLIG2 progenitors and high numbers of OPCs within 75 days. Furthermore, we show the generation of viral and integration-free iPSCs from primary progressive MS (PPMS patients and their efficient differentiation to oligodendrocytes. PPMS OPCs are functional, as demonstrated by in vivo myelination in the shiverer mouse. These results provide encouraging advances toward the development of autologous cell therapies using iPSCs.

  5. T-cell libraries allow simple parallel generation of multiple peptide-specific human T-cell clones

    Science.gov (United States)

    Theaker, Sarah M.; Rius, Cristina; Greenshields-Watson, Alexander; Lloyd, Angharad; Trimby, Andrew; Fuller, Anna; Miles, John J.; Cole, David K.; Peakman, Mark; Sewell, Andrew K.; Dolton, Garry

    2016-01-01

    Isolation of peptide-specific T-cell clones is highly desirable for determining the role of T-cells in human disease, as well as for the development of therapies and diagnostics. However, generation of monoclonal T-cells with the required specificity is challenging and time-consuming. Here we describe a library-based strategy for the simple parallel detection and isolation of multiple peptide-specific human T-cell clones from CD8+ or CD4+ polyclonal T-cell populations. T-cells were first amplified by CD3/CD28 microbeads in a 96U-well library format, prior to screening for desired peptide recognition. T-cells from peptide-reactive wells were then subjected to cytokine-mediated enrichment followed by single-cell cloning, with the entire process from sample to validated clone taking as little as 6 weeks. Overall, T-cell libraries represent an efficient and relatively rapid tool for the generation of peptide-specific T-cell clones, with applications shown here in infectious disease (Epstein–Barr virus, influenza A, and Ebola virus), autoimmunity (type 1 diabetes) and cancer. PMID:26826277

  6. Theoretical Efficiency of 3rd Generation Solar Cells: Comparison between Carrier Multiplication and Down-Conversion

    Science.gov (United States)

    2012-01-01

    p-n junction solar cells, Journal of Applied Physics 32 (1961) 510–519. [2] C.H. Henry, Limiting efficiencies of ideal single and multiple energy gap...terrestrial solar cells, Journal of Applied Physics 51 (1980) 4494–4500. [3] M. Wolf, Limitations and possibilities for improvement of photovoltaic...multiplication absorbers, Journal of Applied Physics 100 (2006) 074510–074517. [6] J.A. Mcquire, J. Joo, J.M. Pietryga, R.D. Schaller, V.I. Klimov

  7. Monitoring multiple myeloma by next-generation sequencing of V(D)J rearrangements from circulating myeloma cells and cell-free myeloma DNA.

    Science.gov (United States)

    Oberle, Anna; Brandt, Anna; Voigtlaender, Minna; Thiele, Benjamin; Radloff, Janina; Schulenkorf, Anita; Alawi, Malik; Akyüz, Nuray; März, Manuela; Ford, Christopher T; Krohn-Grimberghe, Artus; Binder, Mascha

    2017-02-09

    Recent studies suggest that circulating tumor cells and cell-free DNA may represent powerful non-invasive tools for disease monitoring in patients with solid and hematological malignancies. Here, we conducted a pilot study in 27 myeloma patients to explore the clonotypic V(D)J rearrangement for monitoring of circulating myeloma cells (cmc-V(D)J) and cell-free myeloma DNA (cfm-V(D)J). Next-generation sequencing was used to define the myeloma V(D)J rearrangement and for subsequent peripheral blood tracking after treatment initiation. Positivity for cmc-/cfm-V(D)J was associated with conventional remission status (pJ (pJ despite persistent M-protein, suggesting that these markers are less inert than the M-protein, rely more on cell turnover and therefore decline more rapidly after initiation of effective treatment. Positivity for cmc- and cfm-V(D)J was associated with each other (p=0.042), but in 30% discordant. This indicated that cfm-V(D)J may not be generated entirely by circulating myeloma cells and may reflect overall tumor burden. Prospective studies need to define the predictive potential of high-sensitivity determination of circulating myeloma cells and DNA in the monitoring of multiple myeloma.

  8. Multiple Exciton Generation in Colloidal Nanocrystals

    Directory of Open Access Journals (Sweden)

    Charles Smith

    2013-12-01

    Full Text Available In a conventional solar cell, the energy of an absorbed photon in excess of the band gap is rapidly lost as heat, and this is one of the main reasons that the theoretical efficiency is limited to ~33%. However, an alternative process, multiple exciton generation (MEG, can occur in colloidal quantum dots. Here, some or all of the excess energy is instead used to promote one or more additional electrons to the conduction band, potentially increasing the photocurrent of a solar cell and thereby its output efficiency. This review will describe the development of this field over the decade since the first experimental demonstration of multiple exciton generation, including the controversies over experimental artefacts, comparison with similar effects in bulk materials, and the underlying mechanisms. We will also describe the current state-of-the-art and outline promising directions for further development.

  9. Single-Cell Analysis and Next-Generation Immuno-Sequencing Show That Multiple Clones Persist in Patients with Chronic Lymphocytic Leukemia.

    Directory of Open Access Journals (Sweden)

    Jitra Kriangkum

    Full Text Available The immunoglobulin heavy chain (IGH gene rearrangement in chronic lymphocytic leukemia (CLL provides a unique molecular signature; however, we demonstrate that 26/198 CLL patients (13% had more than one IGH rearrangement, indicating the power of molecular technology over phenotypic analysis. Single-cell PCR analysis and next-generation immuno-sequencing identified IGH-defined clones. In 23% (18/79 of cases whose clones carried unmutated immunoglobulin heavy chain variable (IGHV genes (U-CLL, IGH rearrangements were bialleic with one productive (P and one non-productive (NP allele. Two U-CLL were biclonal, each clone being monoallelic (P. In 119 IGHV-mutated (M-CLL cases, one had biallelic rearrangements in their CLL (P/NP and five had 2-4 distinct clones. Allelic exclusion was maintained in all B-clones analyzed. Based on single-cell PCR analysis, 5/11 partner clones (45% reached levels of >5x10(9 cells/L, suggesting second CLL clones. Partner clones persisted over years. Conventional IGH characterization and next-generation sequencing of 13 CLL, 3 multiple myeloma, 2 Waldenstrom's macroglobulinemia and 3 age-matched healthy donors consistently identified the same rearranged IGH sequences. Most multiple clones occurred in M-CLL, perhaps indicative of weak clonal dominance, thereby associating with a good prognosis. In contrast, biallelic CLL occurred primarily in U-CLL thus being associated with poor prognosis. Extending beyond intra-clonal diversity, molecular analysis of clonal evolution and apparent subclones in CLL may also reflect inter-clonal diversity.

  10. Harmonic generation with multiple wiggler schemes

    Energy Technology Data Exchange (ETDEWEB)

    Bonifacio, R.; De Salvo, L.; Pierini, P. [Universita degli Studi, Milano (Italy)

    1995-02-01

    In this paper the authors give a simple theoretical description of the basic physics of the single pass high gain free electron laser (FEL), describing in some detail the FEL bunching properties and the harmonic generation technique with a multiple-wiggler scheme or a high gain optical klystron configuration.

  11. Multiple runoff processes and multiple thresholds control agricultural runoff generation

    Science.gov (United States)

    Saffarpour, Shabnam; Western, Andrew W.; Adams, Russell; McDonnell, Jeffrey J.

    2016-11-01

    Thresholds and hydrologic connectivity associated with runoff processes are a critical concept for understanding catchment hydrologic response at the event timescale. To date, most attention has focused on single runoff response types, and the role of multiple thresholds and flow path connectivities has not been made explicit. Here we first summarise existing knowledge on the interplay between thresholds, connectivity and runoff processes at the hillslope-small catchment scale into a single figure and use it in examining how runoff response and the catchment threshold response to rainfall affect a suite of runoff generation mechanisms in a small agricultural catchment. A 1.37 ha catchment in the Lang Lang River catchment, Victoria, Australia, was instrumented and hourly data of rainfall, runoff, shallow groundwater level and isotope water samples were collected. The rainfall, runoff and antecedent soil moisture data together with water levels at several shallow piezometers are used to identify runoff processes in the study site. We use isotope and major ion results to further support the findings of the hydrometric data. We analyse 60 rainfall events that produced 38 runoff events over two runoff seasons. Our results show that the catchment hydrologic response was typically controlled by the Antecedent Soil Moisture Index and rainfall characteristics. There was a strong seasonal effect in the antecedent moisture conditions that led to marked seasonal-scale changes in runoff response. Analysis of shallow well data revealed that streamflows early in the runoff season were dominated primarily by saturation excess overland flow from the riparian area. As the runoff season progressed, the catchment soil water storage increased and the hillslopes connected to the riparian area. The hillslopes transferred a significant amount of water to the riparian zone during and following events. Then, during a particularly wet period, this connectivity to the riparian zone, and

  12. Multiple Generations on Video Tape Recorders.

    Science.gov (United States)

    Wiens, Jacob H.

    Helical scan video tape recorders were tested for their dubbing characteristics in order to make selection data available to media personnel. The equipment, two recorders of each type tested, was submitted by the manufacturers. The test was designed to produce quality evaluations for three generations of a single tape, thereby encompassing all…

  13. Tag cloud generation for results of multiple keywords queries

    DEFF Research Database (Denmark)

    2013-01-01

    In this paper we study tag cloud generation for retrieved results of multiple keyword queries. It is motivated by many real world scenarios such as personalization tasks, surveillance systems and information retrieval tasks defined with multiple keywords. We adjust the state-of-the-art tag cloud...... generation techniques for multiple keywords query results. Consequently, we conduct the extensive evaluation on top of three distinct collaborative tagging systems. The graph-based methods perform significantly better for the Movielens and Bibsonomy datasets. Tag cloud generation based on maximal coverage...

  14. Multiple myeloma cancer stem cells

    Science.gov (United States)

    Gao, Minjie; Kong, Yuanyuan; Yang, Guang; Gao, Lu; Shi, Jumei

    2016-01-01

    Multiple myeloma (MM) remains incurable despite much progress that has been made in the treatment of the disease. MM cancer stem cell (MMSC), a rare subpopulation of MM cells with the capacity for self-renewal and drug resistance, is considered to lead to disease relapse. Several markers such as side population (SP) and ALDH1+ have been used to identify MMSCs. However, ideally and more precisely, the identification of the MMSCs should rely on MMSCs phenotype. Unfortunately the MMSC phenotype has not been properly defined yet. Drug resistance is the most important property of MMSCs and contributes to disease relapse, but the mechanisms of drug resistance have not been fully understood. The major signaling pathways involved in the regulation of self-renewal and differentiation of MMSCs include Hedgehog (Hh), Wingless (Wnt), Notch and PI3K/Akt/mTOR. However, the precise role of these signaling pathways needs to be clarified. It has been reported that the microRNA profile of MMSCs is remarkably different than that of non-MMSCs. Therefore, the search for targeting MMSCs has also been focused on microRNAs. Complex and mutual interactions between the MMSC and the surrounding bone marrow (BM) microenvironment sustain self-renewal and survival of MMSC. However, the required molecules for the interaction of the MMSC and the surrounding BM microenvironment need to be further identified. In this review, we summarize the current state of knowledge of MMSCs regarding their phenotype, mechanisms of drug resistance, signaling pathways that regulate MMSCs self-renewal and differentiation, abnormal microRNAs expression, and their interactions with the BM microenvironment. PMID:27007154

  15. Generation of multiple-particle cluster state via cavity QED

    Institute of Scientific and Technical Information of China (English)

    Lin Gong-Wei; Lin Xiu-Min; Chen Li-Bo; Du Qian-Hua; Chen Zhi-Hua

    2008-01-01

    This paper proposes schemes for generating multiple-photon and multiple-atom cluster states,respectively.The schemes are based on the cavity input-output process and atomic or photonic states measurement,and the successful probabilities approach unity in the ideal case.The numerical simulations show that the produced multiple-particle cluster states have high fidelity even if the Lamb-Dicke condition is not satisfied.Some practical imperfections,such as atomic spontaneous emission and output coupling inefficiency,only decrease the success probability but exert no influence on the fidelity of generated multiple-particle cluster states. From the experimental point of view,smaller operation number and lack of need for individual addressing keeps the schemes easy to implement.These schemes may offer a promising approach to the generation of a large-scale cluster state.

  16. Targeting Mcl-1 for multiple myeloma (MM) therapy: drug-induced generation of Mcl-1 fragment Mcl-1(128-350) triggers MM cell death via c-Jun upregulation.

    Science.gov (United States)

    Fan, Fengjuan; Tonon, Giovanni; Bashari, Muhammad Hasan; Vallet, Sonia; Antonini, Elena; Goldschmidt, Hartmut; Schulze-Bergkamen, Henning; Opferman, Joseph T; Sattler, Martin; Anderson, Kenneth C; Jäger, Dirk; Podar, Klaus

    2014-02-28

    Myeloid cell leukemia-1 (Mcl-1, HGNC: 6943), a pro-survival member of the Bcl-2 family, plays a crucial role in Multiple Myeloma (MM) pathogenesis and drug resistance, thus representing a promising therapeutic target in MM. A novel strategy to inhibit Mcl-1 activity is the induction of ubiquitin-independent Mcl-1 degradation. Our own and other previous studies have demonstrated caspase-dependent generation of a 28kDa Mcl-1 fragment, Mcl-1(128-350), which inhibits MM cell proliferation and survival. Here, we show that similar to bortezomib, the novel proteasome inhibitors carfilzomib and ixazomib, as well as staurosporine and adaphostin, induce the generation of Mcl-1(128-350) in MM cells. Next, the molecular sequelae downstream of Mcl-1(128-350), which mediate its pro-apoptotic activity, were delineated. Surprisingly, we observed nuclear accumulation of drug-induced or exogenously overexpressed Mcl-1(128-350), followed by elevated mRNA and protein levels of c-Jun, as well as enhanced AP-1 reporter activity. Moreover, drug-induced AP-1 activity was blocked after introducing a point mutation into the highly conserved Mcl-1 caspase-cleavage site Asp127, but not Asp157. Consequently, drug-triggered cell death was significantly decreased in MM cells transfected with Mcl-1 D127A, but not with Mcl-1 D157A. Consistent with these data, treatment with bortezomib triggered c-Jun upregulation followed by apoptosis in Mcl-1(wt/wt), but not Mcl-1(Δ/null) murine embryonic fibroblasts (MEFs). Transfection of a plasmid carrying Mcl-1(wt) into Mcl-1(Δ/null) MEFs restored bortezomib-induced Mcl-1 fragmentation, c-Jun upregulation and AP-1 reporter activity. Finally, our data indicate that drug-induced generation of a pro-apoptotic Mcl-1 fragment followed by c-Jun upregulation may also be a novel therapeutic approach in other tumor entities.

  17. Characterization of clonogenic multiple myeloma cells

    OpenAIRE

    Matsui, William; Huff, Carol Ann; Wang, Qiuju; Malehorn, Matthew T.; Barber, James; Tanhehco, Yvette; Smith, B Douglas; Civin, Curt I.; Jones, Richard J.

    2003-01-01

    The identity of the cells responsible for the initiation and maintenance of multiple myeloma (MM) remains unclear largely because of the difficulty growing MM cells in vitro and in vivo. MM cell lines and clinical specimens are characterized by malignant plasma cells that express the cell surface antigen syndecan-1 (CD138); however, CD138 expression is limited to terminally differentiated plasma cells during B-cell development. Moreover, circulating B cells that are clonally related to MM pla...

  18. Generation of multiple excitons in Ag2S quantum dots: Single high-energy versus multiple-photon excitation

    KAUST Repository

    Sun, Jingya

    2014-02-20

    We explored biexciton generation via carrier multiplication (or multiple-exciton generation) by high-energy photons and by multiple-photon absorption in Ag2S quantum dots (QDs) using femtosecond broad-band transient absorption spectroscopy. Irrespective of the size of the QDs and how the multiple excitons are generated in the Ag2S QDs, two distinct characteristic time constants of 9.6-10.2 and 135-175 ps are obtained for the nonradiative Auger recombination of the multiple excitons, indicating the existence of two binding excitons, namely, tightly bound and weakly bound excitons. More importantly, the lifetimes of multiple excitons in Ag 2S QDs were about 1 and 2 orders of magnitude longer than those of comparable size PbS QDs and single-walled carbon nanotubes, respectively. This result is significant because it suggests that by utilizing an appropriate electron acceptor, there is a higher possibility to extract multiple electron-hole pairs in Ag2S QDs, which should improve the performance of QD-based solar cell devices. © 2014 American Chemical Society.

  19. Dense pattern multiple pass cells

    Science.gov (United States)

    Silver, Joel A.; Bomse, David S.

    2010-09-21

    An optical cell and a method of operating an optical cell comprising employing a first mirror comprising a first hole therein at approximately a center of the first mirror and through which laser light enters the cell, employing a second mirror comprising a second hole therein at approximately a center of the second mirror and through which laser light exits the cell, and forming a Lissajous pattern of spots on the mirrors by repeated reflection of laser light entering the cell.

  20. Color Correction in Multiple Generation Reproduction Using Digital Watermarking

    Institute of Scientific and Technical Information of China (English)

    Zhigang Fan; Shen-ge Wang; Hui Cheng

    2004-01-01

    In most existing color reproduction systems, color correction is performed in an open-looped fashion.For multiple generation color copying, color fidelity cannot be guaranteed as the errors introduced in color correction may accumulate. A method of solving the error accumulation problem by embedding color information as invisible digital watermark in hardcopies is proposed. When the hardcopy is scanned, the embedded information can be retrieved to provide real-time calibration. As the method is close-looped in nature, it may reduce error accumulation and improve color fidelity, particularly when copies go through multiple generation reproduction.

  1. Third generation photovoltaics based on multiple exciton generation in quantum confined semiconductors.

    Science.gov (United States)

    Beard, Matthew C; Luther, Joseph M; Semonin, Octavi E; Nozik, Arthur J

    2013-06-18

    Improving the primary photoconversion process in a photovoltaiccell by utilizing the excess energy that is otherwise lost as heat can lead to an increase in the overall power conversion efficiency (PCE). Semiconductor nanocrystals (NCs) with at least one dimension small enough to produce quantum confinement effects provide new ways of controlling energy flow not achievable in thin film or bulk semiconductors. Researchers have developed various strategies to incorporate these novel structures into suitable solar conversion systems. Some of these methods could increase the PCE past the Shockley-Queisser (SQ) limit of ∼33%, making them viable "third generation photovoltaic" (TGPV) cell architectures. Surpassing the SQ limit for single junction solar cells presents both a scientific and a technological challenge, and the use of semiconductor NCs to enhance the primary photoconversion process offers a promising potential solution. The NCs are synthesized via solution phase chemical reactions producing stable colloidal solutions, where the reaction conditions can be modified to produce a variety of shapes, compositions, and structures. The confinement of the semiconductor NC in one dimension produces quantum films, wells, or discs. Two-dimensional confinement leads to quantum wires or rods (QRs), and quantum dots (QDs) are three-dimensionally confined NCs. The process of multiple exciton generation (MEG) converts a high-energy photon into multiple electron-hole pairs. Although many studies have demonstrated that MEG is enhanced in QDs compared with bulk semiconductors, these studies have either used ultrafast spectroscopy to measure the photon-to-exciton quantum yields (QYs) or theoretical calculations. Implementing MEG in a working solar cell has been an ongoing challenge. In this Account, we discuss the status of MEG research and strategies towards implementing MEG in working solar cells. Recently we showed an external quantum efficiency for photocurrent of greater

  2. 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.

  3. Multiple THz pulse generation with variable energy ratio and delay

    Science.gov (United States)

    Ungureanu, R. G.; Grigore, O. V.; Dinca, M. P.; Cojocaru, G. V.; Ursescu, D.; Dascalu, T.

    2015-04-01

    Two methods for multiple high energetic THz pulse generation by two-color filamentation in air with controllable energy ratio and delay ranging from one to hundreds of ps were investigated. In the first method the laser pulse is split into two inside the optical stretcher of a CPA laser system, the resulting consecutive filaments occur in the same region and allows the study of the influence of the first plasma filament on the THz emission of the delayed filament. Based on a polarization sensitive thin film beam splitter placed in front of a 45° mirror, the second method produces multiple parallel consecutive filaments. Above a certain total pump level the THz energy delivered by multiple pulses exceeds the value given by a single filament for the same pump energy, thereby overcoming the THz emission saturation of the single filament.

  4. Fast generation of dendritic cells

    DEFF Research Database (Denmark)

    Kvistborg, P; Bøgh, Marie; Claesson, M H

    2009-01-01

    we have developed fast DC protocol by comparing two different fast DC protocols with SDDC. DC were evaluated by FACS analysis, and the optimal profile was considered: CD14(low), CD80(high), CD83(high), CD86(high), CCR7(high), HLA class I and II(high). FACS profiles were used as the selection criteria...... together with yield and morphology. Two fast DC protocols fulfilled these criteria and were selected for functional analysis. Our results demonstrate that DC generated within 5days or 48h are comparable with SDDC both phenotypically and functionally. However, we found that 48h DC were more susceptible than...... SDDC to the IL-10 inducing stimulus of TLR ligands (R848 and LPS). Thus to determine the clinical relevance of fast DC protocols in cancer settings, small phase I trials should be conducted monitoring regulatory T cells carefully....

  5. 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.

  6. Multiple coaxial foci generation by phase-only pupil filters

    Science.gov (United States)

    Valle, Pedro J.; Oti, José E.; Canales, Vidal F.; Cagigal, Manuel P.

    2007-04-01

    A new procedure for creating simultaneous multiple foci along the same optical axis with phase-only pupil-plane filters is proposed. Pupil-plane filters consist in phase-only masks described by simple circularly symmetric analytical functions. The axial separation between foci and their energy distribution are independently controlled by two different parameters of the filter. The main advantage of this new design is that, unlike other methods that required slow iterative algorithms, the proposed phase masks are straightforwardly calculated from analytical expressions. Moreover, real-time dynamic foci control could be achieved by using a computer addressed spatial light modulator that allowed the generation of variable phase patterns. The phase profiles we propose can be combined with multiple transversal foci phase patterns to actually form axial replicas of the transversal foci. Thus, it should be expected that three-dimensional structures were dynamically driven fast enough to perform real-time interactive multiple foci manipulation. Experimental verification of the multiple coaxial foci creation by static phase filters is shown.

  7. Biorthogonal multiple wavelets generated by vector refinement equation

    Institute of Scientific and Technical Information of China (English)

    Song LI; Jun XIAN

    2007-01-01

    Biorthogonal multiple wavelets are generated from refinable function vectors by using the multiresolution analysis. In this paper we provide a general method for the construction of compactly supported biorthogonal multiple wavelets by refinable function vectors which are the solutions of vector refinement equations of the formψ(x) =∑α∈Zs α(α)ψ(Mx-α), x ∈ Rs,sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that limn→∞ M-n = 0. Our characterizations are in the general setting and the main results of this paper are the real extensions of some known results.

  8. Biorthogonal multiple wavelets generated by vector refinement equation

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Biorthogonal multiple wavelets are generated from refinable function vectors by using the multiresolution analysis.In this paper we provide a general method for the construction of compactly supported biorthogonal multiple wavelets by refinable function vectors which are the solutions of vector refinement equations of the form (?)(x)=(?)a(α)(?)(Mx-α),x∈Rs, where the vector of functions(?)=((?)1,...,(?)r)T is in(L2(Rs))r,a=:(a(α))α∈Zsis a finitely supported sequence of r×r matrices called the refinement mask,and M is an s×s integer matrix such that limn→∞M-n=0.Our characterizations are in the general setting and the main results of this paper are the real extensions of some known results.

  9. Automatic Generation of 3D Building Models with Multiple Roofs

    Institute of Scientific and Technical Information of China (English)

    Kenichi Sugihara; Yoshitugu Hayashi

    2008-01-01

    Based on building footprints (building polygons) on digital maps, we are proposing the GIS and CG integrated system that automatically generates 3D building models with multiple roofs. Most building polygons' edges meet at right angles (orthogonal polygon). The integrated system partitions orthogonal building polygons into a set of rectangles and places rectangular roofs and box-shaped building bodies on these rectangles. In order to partition an orthogonal polygon, we proposed a useful polygon expression in deciding from which vertex a dividing line is drawn. In this paper, we propose a new scheme for partitioning building polygons and show the process of creating 3D roof models.

  10. Octave-spanning supercontinuum generation via microwave frequency multiplication

    Science.gov (United States)

    Cole, D. C.; Beha, K. M.; Diddams, S. A.; Papp, S. B.

    2016-06-01

    We demonstrate a system based on telecom components for the generation of a coherent octave-spanning supercontinuum from a continuous-wave laser. The system utilizes direct multiplication of a 10 GHz signal derived from a commercial synthesizer to carve pulses from the laser, which are then iteratively chirped and compressed in two stages. After reducing the repetition rate of the resulting pulse train to 2.5 GHz using selective transmission through an electro-optic gate, propagation through highly-nonlinear fiber generates an octave-spanning supercontinuum spectrum. We discuss the impact of the noise of the modulation frequency on the coherence of the supercontinuum and discuss its mitigation. Close agreement between experiment and theory is shown throughout, and we use our ability to precisely model the experiment to propose an extension of the system to 20 GHz repetition rate.

  11. Hematopoietic stem cell transplantation in multiple sclerosis

    DEFF Research Database (Denmark)

    Rogojan, C; Frederiksen, J L

    2009-01-01

    Intensive immunosuppresion followed by hematopoietic stem cell transplantation (HSCT) has been suggested as potential treatment in severe forms of multiple sclerosis (MS). Since 1995 ca. 400 patients have been treated with HSCT. Stabilization or improvement occurred in almost 70% of cases at least...

  12. Multiplicative ARMA models to generate hourly series of global irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Mora-Lopez, L. [Universidad de Malaga (Spain). Dpto. Lenguajes y C. Computacion; Sidrach-de-Cardona, M. [Universidad de Malaga (Spain). Dpto. Fisica Aplicada

    1998-11-01

    A methodology to generate hourly series of global irradiation is proposed. The only input parameter which is required is the monthly mean value of daily global irradiation, which is available for most locations. The procedure to obtain new series is based on the use of a multiplicative autoregressive moving-average statistical model for time series with regular and seasonal components. The multiplicative nature of these models enables capture of the two types of relationships observed in recorded hourly series of global irradiation: on the one hand, the relationship between the value at one hour and the value at the previous hour; and on the other hand, the relationship between the value at one hour in one day and the value at the same hour in the previous day. In this paper the main drawback which arises when using these models to generate new series is solved: namely, the need for available recorded series in order to obtain the three parameters contained in the statistical ARMA model which is proposed (autoregressive coefficient, moving-average coefficient and variance of the error term). Specifically, expressions which enable estimation of these parameters using only monthly mean values of daily global irradiation are proposed in this paper. (author)

  13. Smart Energy Management of Multiple Full Cell Powered Applications

    Energy Technology Data Exchange (ETDEWEB)

    Mohammad S. Alam

    2007-04-23

    In this research project the University of South Alabama research team has been investigating smart energy management and control of multiple fuel cell power sources when subjected to varying demands of electrical and thermal loads together with demands of hydrogen production. This research has focused on finding the optimal schedule of the multiple fuel cell power plants in terms of electric, thermal and hydrogen energy. The optimal schedule is expected to yield the lowest operating cost. Our team is also investigating the possibility of generating hydrogen using photoelectrochemical (PEC) solar cells through finding materials for efficient light harvesting photoanodes. The goal is to develop an efficient and cost effective PEC solar cell system for direct electrolysis of water. In addition, models for hydrogen production, purification, and storage will be developed. The results obtained and the data collected will be then used to develop a smart energy management algorithm whose function is to maximize energy conservation within a managed set of appliances, thereby lowering O/M costs of the Fuel Cell power plant (FCPP), and allowing more hydrogen generation opportunities. The Smart Energy Management and Control (SEMaC) software, developed earlier, controls electrical loads in an individual home to achieve load management objectives such that the total power consumption of a typical residential home remains below the available power generated from a fuel cell. In this project, the research team will leverage the SEMaC algorithm developed earlier to create a neighborhood level control system.

  14. B Cells and Autoantibodies in Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Anne-Katrin Pröbstel

    2015-07-01

    Full Text Available While over the past decades T cells have been considered key players in the pathogenesis of multiple sclerosis (MS, it has only recently become evident that B cells have a major contributing role. Our understanding of the role of B cells has evolved substantially following the clinical success of B cell-targeting therapies and increasing experimental evidence for significant B cell involvement. Rather than mere antibody-producing cells, it is becoming clear that they are team players with the capacity to prime and regulate T cells, and function both as pro- and anti-inflammatory mediators. However, despite tremendous efforts, the target antigen(s of B cells in MS have yet to be identified. The first part of this review summarizes the clinical evidence and results from animal studies pointing to the relevance of B cells in the pathogenesis of MS. The second part gives an overview of the currently known potential autoantigen targets. The third part recapitulates and critically appraises the currently available B cell-directed therapies.

  15. Multiple footprint stereo algorithms for 3D display content generation

    Science.gov (United States)

    Boughorbel, Faysal

    2007-02-01

    This research focuses on the conversion of stereoscopic video material into an image + depth format which is suitable for rendering on the multiview auto-stereoscopic displays of Philips. The recent interest shown in the movie industry for 3D significantly increased the availability of stereo material. In this context the conversion from stereo to the input formats of 3D displays becomes an important task. In this paper we present a stereo algorithm that uses multiple footprints generating several depth candidates for each image pixel. We characterize the various matching windows and we devise a robust strategy for extracting high quality estimates from the resulting depth candidates. The proposed algorithm is based on a surface filtering method that employs simultaneously the available depth estimates in a small local neighborhood while ensuring correct depth discontinuities by the inclusion of image constraints. The resulting highquality image-aligned depth maps proved an excellent match with our 3D displays.

  16. Salvage Therapy of Multiple Myeloma: The New Generation Drugs

    Directory of Open Access Journals (Sweden)

    Alessandra Romano

    2014-01-01

    Full Text Available During the past decade, overall results of treatment of multiple myeloma (MM have been improved and survival curves are now significantly better with respect to those obtained with historical treatment. These improvements are linked to a deeper knowledge of the biology of disease and to the introduction in clinical practice of drugs with different mechanism of action such as proteasome inhibitors and immunomodulatory drugs (IMiDs. However, MM remains in most cases an incurable disease. For patients who relapse after treatment with novel agents, the prognosis is dismal and new drugs and therapeutic strategies are required for continued disease control. In this review, we summarize new insights in salvage therapy for relapsed/refractory MM as emerging from recent clinical trials exploring the activity of bendamustine, new generation proteasome inhibitors, novel IMiDs, monoclonal antibodies, and drugs interfering with growth pathways.

  17. Dopamine, T cells and multiple sclerosis (MS).

    Science.gov (United States)

    Levite, Mia; Marino, Franca; Cosentino, Marco

    2017-03-10

    Dopamine is a key neurotransmitter that induces critical effects in the nervous system and in many peripheral organs, via 5 dopamine receptors (DRs): D1R-D5R. Dopamine also induces many direct and very potent effects on many DR-expressing immune cells, primarily T cells and dendritic cells. In this review, we focus only on dopamine receptors, effects and production in T cells. Dopamine by itself (at an optimal concentration of~0.1 nM) induces multiple function of resting normal human T cells, among them: T cell adhesion, chemotactic migration, homing, cytokine secretion and others. Interestingly, dopamine activates resting effector T cells (Teffs), but suppresses regulatory T cells (Tregs), and both effects lead eventually to Teff activation. Dopamine-induced effects on T cells are dynamic, context-sensitive and determined by the: T cell activation state, T cell type, DR type, and dopamine concentration. Dopamine itself, and also few dopaminergic molecules/ drugs that are in clinical use for cardiac, neurological and other non-immune indications, have direct effects on human T cells (summarized in this review). These dopaminergic drugs include: dopamine = intropin, L-DOPA, bromocriptine, pramipexole, pergolide, haloperidol, pimozide, and amantadine. Other dopaminergic drugs were not yet tested for their direct effects on T cells. Extensive evidence in multiple sclerosis (MS) and experimental autoimmune encephalomyelitis (EAE) show dopaminergic dysregulations in T cells in these diseases: D1-like DRs are decreased in Teffs of MS patients, and dopamine does not affect these cells. In contrast, D1-like DRs are increased in Tregs of MS patients, possibly causing functional Treg impairment in MS. Treatment of MS patients with interferon β (IFN-β) increases D1-like DRs and decreases D2-like DRs in Teffs, decreases D1-like DRs in Tregs, and most important: restores responsiveness of patient's Teffs to dopamine. DR agonists and antagonists confer some benefits in

  18. Generation of functional eyes from pluripotent cells.

    Directory of Open Access Journals (Sweden)

    Andrea S Viczian

    2009-08-01

    Full Text Available Pluripotent cells such as embryonic stem (ES and induced pluripotent stem (iPS cells are the starting point from which to generate organ specific cell types. For example, converting pluripotent cells to retinal cells could provide an opportunity to treat retinal injuries and degenerations. In this study, we used an in vivo strategy to determine if functional retinas could be generated from a defined population of pluripotent Xenopus laevis cells. Animal pole cells isolated from blastula stage embryos are pluripotent. Untreated, these cells formed only epidermis, when transplanted to either the flank or eye field. In contrast, misexpression of seven transcription factors induced the formation of retinal cell types. Induced retinal cells were committed to a retinal lineage as they formed eyes when transplanted to the flanks of developing embryos. When the endogenous eye field was replaced with induced retinal cells, they formed eyes that were molecularly, anatomically, and electrophysiologically similar to normal eyes. Importantly, induced eyes could guide a vision-based behavior. These results suggest the fate of pluripotent cells may be purposely altered to generate multipotent retinal progenitor cells, which differentiate into functional retinal cell classes and form a neural circuitry sufficient for vision.

  19. NTPDase2+ cells generate lingual epithelia and papillae

    Directory of Open Access Journals (Sweden)

    Li eFeng

    2012-11-01

    Full Text Available The tongue epithelium is one of the most rapidly self-renewing tissues in adult mammals. Multiple stem cell populations are currently believed to exist in tongue epithelia. Keratin 14 (K14 positive cells differentiate into either lingual epithelia or lingual papillae, while ecto-nucleoside triphosphate diphosphohydrolase 2 (NTPDase2 is associated with neural stem cells and astrocyte-like cells ensheathing the migrating neuroblasts. Here, using a transgenic mouse expressing rtTA from the mouse NTPDase2 promoter, we generated an inducible model by treatment with Doxycycline. By immunohistochemical analysis and in situ hybridization, we found exclusive expression of NTPDase2 in lingual epithelia and lingual papillae. Using inducible genetic cell fate mapping, we further showed that the NTPDase2+ cells generated lingual papillae and epithelia in the adult tongue. Finally, building on our previously proposed paradigm of cell migration stream, a model is further described here for lingual epithelia cell genesis. In short, the current results not only extend our understanding of the cell migration stream in lingual epithelia and lingual papillae, but they also support the concept of multiple stem cell populations in lingual epithelia and papillae.

  20. Microfluidic fuel cells for energy generation.

    Science.gov (United States)

    Safdar, M; Jänis, J; Sánchez, S

    2016-08-07

    Sustainable energy generation is of recent interest due to a growing energy demand across the globe and increasing environmental issues caused by conventional non-renewable means of power generation. In the context of microsystems, portable electronics and lab-on-a-chip based (bio)chemical sensors would essentially require fully integrated, reliable means of power generation. Microfluidic-based fuel cells can offer unique advantages compared to conventional fuel cells such as high surface area-to-volume ratio, ease of integration, cost effectiveness and portability. Here, we summarize recent developments which utilize the potential of microfluidic devices for energy generation.

  1. Generation of Multiple Metadata Formats from a Geospatial Data Repository

    Science.gov (United States)

    Hudspeth, W. B.; Benedict, K. K.; Scott, S.

    2012-12-01

    The Earth Data Analysis Center (EDAC) at the University of New Mexico is partnering with the CYBERShARE and Environmental Health Group from the Center for Environmental Resource Management (CERM), located at the University of Texas, El Paso (UTEP), the Biodiversity Institute at the University of Kansas (KU), and the New Mexico Geo- Epidemiology Research Network (GERN) to provide a technical infrastructure that enables investigation of a variety of climate-driven human/environmental systems. Two significant goals of this NASA-funded project are: a) to increase the use of NASA Earth observational data at EDAC by various modeling communities through enabling better discovery, access, and use of relevant information, and b) to expose these communities to the benefits of provenance for improving understanding and usability of heterogeneous data sources and derived model products. To realize these goals, EDAC has leveraged the core capabilities of its Geographic Storage, Transformation, and Retrieval Engine (Gstore) platform, developed with support of the NSF EPSCoR Program. The Gstore geospatial services platform provides general purpose web services based upon the REST service model, and is capable of data discovery, access, and publication functions, metadata delivery functions, data transformation, and auto-generated OGC services for those data products that can support those services. Central to the NASA ACCESS project is the delivery of geospatial metadata in a variety of formats, including ISO 19115-2/19139, FGDC CSDGM, and the Proof Markup Language (PML). This presentation details the extraction and persistence of relevant metadata in the Gstore data store, and their transformation into multiple metadata formats that are increasingly utilized by the geospatial community to document not only core library catalog elements (e.g. title, abstract, publication data, geographic extent, projection information, and database elements), but also the processing steps used to

  2. Identify multiple myeloma stem cells: Utopia?

    Science.gov (United States)

    Saltarella, Ilaria; Lamanuzzi, Aurelia; Reale, Antonia; Vacca, Angelo; Ria, Roberto

    2015-01-26

    Multiple myeloma (MM) is a hematologic malignancy of monoclonal plasma cells which remains incurable despite recent advances in therapies. The presence of cancer stem cells (CSCs) has been demonstrated in many solid and hematologic tumors, so the idea of CSCs has been proposed for MM, even if MM CSCs have not been define yet. The existence of myeloma CSCs with clonotypic B and clonotypic non B cells was postulated by many groups. This review aims to focus on these distinct clonotypic subpopulations and on their ability to develop and sustain MM. The bone marrow microenvironment provides to MM CSCs self-renewal, survival and drug resistance thanks to the presence of normal and cancer stem cell niches. The niches and CSCs interact each other through adhesion molecules and the interplay between ligands and receptors activates stemness signaling (Hedgehog, Wnt and Notch pathways). MM CSCs are also supposed to be responsible for drug resistance that happens in three steps from the initial cancer cell homing microenvironment-mediated to development of microenvironment-independent drug resistance. In this review, we will underline all these aspects of MM CSCs.

  3. Equine herpesvirus 1 gene 12 can substitute for vmw65 in the growth of herpes simplex virus (HSV) type 1, allowing the generation of optimized cell lines for the propagation of HSV vectors with multiple immediate-early gene defects.

    Science.gov (United States)

    Thomas, S K; Lilley, C E; Latchman, D S; Coffin, R S

    1999-09-01

    Herpes simplex virus (HSV) has often been suggested for development as a vector, particularly for the nervous system. Considerable evidence has shown that for use of HSV as a vector, immediate-early (IE) gene expression must be minimized or abolished, otherwise such vectors are likely to be highly cytotoxic. Mutations of vmw65 which abolish IE promoter transactivating activity may also be included to reduce IE gene expression generally. However, when vmw65 mutations are combined with an IE gene deletion, such viruses are hard to propagate, even on cells which otherwise complement the IE gene deletion effectively. We have found that vmw65 mutants can be effectively grown on cell lines expressing equine herpesvirus 1 gene 12, a non-HSV homologue of vmw65 with little sequence similarity to its HSV counterpart. This prevents repair by homologous recombination of vmw65 mutations in the virus, which would occur if mutations were complemented by vmw65 itself. The gene 12 protein is not packaged into HSV virions, which is important if viruses grown on such cells are to be used as vectors. These results not only further strengthen the evidence for direct functional homology between and similar modes of action of the two proteins but have allowed the generation of gene 12-containing cell lines in which ICP4 and ICP27 expression is induced by virus infection (probably by ICP0) and which give efficient growth of viruses deficient in ICP27, ICP4, and vmw65 (the viruses also have ICP34.5/ORFP deleted). Efficient growth of such viruses has not previously been possible. As these viruses are highly deficient in IE gene expression generally, such virus-cell line combinations may provide an alternative to HSV vectors with deletions of all four of the regulatory IE genes which, for optimal growth, require cell lines containing all four IE genes but which are hard to generate due to the intrinsic cytotoxicity of each of the proteins.

  4. Synthesis of cadmium chalcogenide based quantum dots for enhanced multiple exciton generation

    OpenAIRE

    2014-01-01

    Quantum dots (QDs) have the potential to produce more than one exciton per incident photon, if the photon energy is greater than twice the band gap energy. This process of multiple exciton generation (MEG) has the potential to lead to a step change in the efficiency of solar panels, by utilising energy commonly wasted as heat in conventional solar cells. A wide range of CdSe/CdTe and CdTe/CdSe quantum dots with and without a CdS shell were synthesised with varying core sizes and shell thickne...

  5. Yours, Mine, Theirs: Multiple Generations in Today's Workplace

    Science.gov (United States)

    Grotophorst, Julie

    2011-01-01

    For the first time in history, four distinct generations are sharing the same workspace. Veterans, Baby Boomers, Gen-Xers, and Generation Y (the Millennials) are all bringing very different life experiences, expectations, and value systems to the work table. How do leaders bridge the gap among these generations and provide common ground on which…

  6. Stages of Plasma Cell Neoplasms (Including Multiple Myeloma)

    Science.gov (United States)

    ... Treatment Health Professional Plasma Cell Neoplasms Treatment Research Plasma Cell Neoplasms (Including Multiple Myeloma) Treatment (PDQ®)–Patient Version General Information About Plasma Cell Neoplasms Go to Health Professional Version Key ...

  7. Multiple Access Techniques for Next Generation Wireless: Recent Advances and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Shree Krishna Sharma

    2016-01-01

    Full Text Available The advances in multiple access techniques has been one of the key drivers in moving from one cellular generation to another. Starting from the first generation, several multiple access techniques have been explored in different generations and various emerging multiplexing/multiple access techniques are being investigated for the next generation of cellular networks. In this context, this paper first provides a detailed review on the existing Space Division Multiple Access (SDMA related works. Subsequently, it highlights the main features and the drawbacks of various existing and emerging multiplexing/multiple access techniques. Finally, we propose a novel concept of clustered orthogonal signature division multiple access for the next generation of cellular networks. The proposed concept envisions to employ joint antenna coding in order to enhance the orthogonality of SDMA beams with the objective of enhancing the spectral efficiency of future cellular networks.

  8. Generation of pancreatic islet cells from human embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Efficiently obtaining functional pancreatic islet cells derived from human embryonic stem(hES) cells not only provides great potential to solve the shortage of islets sources for type I diabetes cell therapy,but also benefits the study of the development of the human pancreas and diabetes pathology.In 2001,hES cells were reported to have the capacity to generate insulin-producing cells by spontaneous differentiation in vitro.Since then,many strategies(such as overexpression of key transcription factors,delivery of key proteins for pancreatic development,co-transplantation of differentiated hES cells along with fetal pancreas,stepwise differentiation by mimicking in vivo pancreatic development) have been employed in order to induce the differentiation of pancreatic islet cells from hES cells.Moreover,patient-specific induced pluripotent stem(iPS) cells can be generated by reprogramming somatic cells.iPS cells have characteristics similar to those of ES cells and offer a new cell source for type I diabetes cell therapy that reduces the risk of immunologic rejection.In this review,we summarize the recent progress made in the differentiation of hES and iPS cells into functional pancreatic islet cells and discuss the challenges for their future study.

  9. Generation of pancreatic islet cells from human embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    ZHANG DongHui; JIANG Wei; SHI Yan; DENG HongKui

    2009-01-01

    Efficiently obtaining functional pancreaUc islet cells derived from human embryonic stem (hES) cells not only provides great potential to solve the shortage of islets sources for type I diabetes cell therapy,but also benefits the study of the development of the human pancreas and diabetes pathology. In 2001,hES cells were reported to have the capacity to generate insulin-producing cells by spontaneous differentiation in vitro. Since then, many strategies (such as overexpression of key transcription factors,delivery of key proteins for pancreatic development, co-transplantation of differentiated hES cells along with fetal pancreas, stepwise differentiation by mimicking in vivo pancreatic development) have been employed in order to induce the differentiation of pancreatic islet cells from hES cells. Moreover, patient-specific induced pluripotent stem (iPS) cells can be generated by reprogramming somatic cells.iPS cells have characteristics similar to those of ES cells and offer a new cell source for type I diabetes cell therapy that reduces the risk of immunologic rejection. In this review, we summarize the recent progress made in the differentiation of hES and iPS cells into functional pancreatic islet cells and discuss the challenges for their future study.

  10. Extremely Efficient Multiple Electron-hole Pair Generation in Carbon Nanotube Photodiodes

    Science.gov (United States)

    Gabor, Nathaniel

    2010-03-01

    The efficient generation of multiple electron-hole (e-h) pairs from a single photon could improve the efficiency of photovoltaic solar cells beyond standard thermodynamic limits [1] and has been the focus of much recent work in semiconductor nanomaterials [2,3]. In single walled carbon nanotubes (SWNTs), the small Fermi velocity and low dielectric constant suggests that electron-electron interactions are very strong and that high-energy carriers should efficiently generate e-h pairs. Here, I will discuss observations of highly efficient generation of e-h pairs due to impact excitation in SWNT p-n junction photodiodes [4]. To investigate optoelectronic transport properties of individual SWNT photodiodes, we focus a laser beam over the device while monitoring the electronic characteristics. Optical excitation into the second electronic subband E22 ˜ 2 EGAP leads to striking photocurrent steps in the device I-VSD characteristics that occur at voltage intervals of the band gap energy EGAP/ e. Spatially and spectrally resolved photocurrent combined with temperature-dependent studies suggest that these steps result from efficient generation of multiple e-h pairs from a single hot E22 carrier. We conclude that in the SWNT photodiode, a single photon with energy greater than 2EGAP is converted into multiple e-h pairs, leading to enhanced photocurrent and increased photo-conversion efficiency. [1] W. Shockley, and H. J. Queisser, Journal of Applied Physics 32, 510 (1961). [2] R. D. Schaller, and V. I. Klimov, Physical Review Letters 92 (18), 186601 (2004). [3] R. J. Ellingson, et al, Nano Letters, 5 (5), 865-871 (2005). [4] Nathaniel M. Gabor, Zhaohui Zhong, Ken Bosnick, Jiwoong Park, and Paul McEuen, Science, 325, 1367 (2009).

  11. Phagocytic plasma cells in a patient with multiple myeloma

    NARCIS (Netherlands)

    P.M. Vanhagen (P.); K. de Leeuw (K.); A. Hagemeijer (Anne); B. Löwenberg (Bob)

    1995-01-01

    textabstractPhagocytosis of blood cells by malignant plasma cells in multiple myeloma is an extremely rare condition. Here we present a 39-year-old woman with multiple myeloma. Bone marrow smear showed an extensive phagocytosis of erythrocytes and platelets by myeloma cells.

  12. MATLAB based language for generating randomized multiple choice questions

    OpenAIRE

    Azamov, Nurulla

    2015-01-01

    In this work we describe a simple MATLAB based language which allows to create randomized multiple choice questions with minimal effort. This language has been successfully tested at Flinders University by the author in a number of mathematics topics including Numerical Analysis, Abstract Algebra and Partial Differential Equations.

  13. New Drive Train Concept with Multiple High Speed Generator

    Science.gov (United States)

    Barenhorst, F.; Serowy, S.; Andrei, C.; Schelenz, R.; Jacobs, G.; Hameyer, K.

    2016-09-01

    In the research project RapidWind (financed by the German Federal Ministry for Economic Affairs and Energy under Grant 0325642) an alternative 6 MW drive train configuration with six high-speed (n = 5000 rpm) permanent magnet synchronous generators for wind turbine generators (WTG) is designed. The gearbox for this drive train concept is assembled with a six fold power split spur gear stage in the first stage, followed by six individual 1 MW geared driven generators. Switchable couplings are developed to connect and disconnect individual geared generators depending on the input power. With this drive train configuration it is possible to improve the efficiency during partial load operation, increasing the energy yield about 1.15% for an exemplary low-wind site. The focus of this paper is the investigation of the dynamic behavior of this new WTG concept. Due to the high gear ratio the inertia relationship between rotor and generator differs from conventional WT concepts, possibly leading to intensified vibration behavior. Moreover there are switching procedures added, that might also lead to vibration issues.

  14. Betulinic acid regulates generation of neuroinflammatory mediators responsible for tissue destruction in multiple sclerosis in vitro

    Institute of Scientific and Technical Information of China (English)

    Jana BLA(Z)EVSKI; Filip PETKOVI(C); Miljana MOM(C)ILOVI(C); Reinhard PASCHKE; Goran N KALUDEROVI(C); Marija MOSTARICA STOJKOVI(C); Djordje MILJKOVI(C)

    2013-01-01

    Aim:To investigate the influences of betulinic acid (BA),a triterpenoid isolated from birch bark,on neuroinflammatory mediators involved in the pathogenesis of multiple sclerosis and experimental autoimmune encephalomyelitis in vitro.Methods:Encephalitogenic T cells were prepared from draining lymph nodes and spinal cords of Dark Agouti rats 8 to 10 d after immunization with myelin basic protein (MBP) and complete Freund's adjuvant.Macrophages were isolated from the peritoneal cavity of adult untreated rats.Astrocytes were isolated from neonatal rat brains.The cells were cultured and then treated with different agents.IFN-y,IL-17,iNOS and CXCL12 mRNA levels in the cells were analyzed with RT-PCR.iNOS and CXCL12 protein levels were detected using immunoblot.NO and ROS generation was measured using Griess reaction and flow cytometry,respectively.Results:In encephalitogenic T cells stimulated with MBP (10 μg/mL),addition of BA inhibited IL-17 and IFN-γ production in a dosedependent manner.The estimated IC50 values for IL-17 and IFN y were 11.2 and 63.8 μmol/L,respectively.When the macrophages were stimulated with LPS (10 ng/mL),addition of BA (50 μmol/L) significantly increased ROS generation,and suppressed NO generation.The astrocytes were stimulated with ConASn containing numerous inflammatory mediators,which mimicked the inflammatory milieu within CNS; addition of BA (50 μmol/L) significantly increased ROS generation,and blocked ConASn-induced increases in iNOS and CXCL12 mRNA levels,but did not affect iNOS and CXCL12 protein levels.Importantly,in both the macrophages and astrocytes,addition of BA (50 μmol/L) inhibited lipid peroxidation.Conclusion:Besides inhibiting encephalitogenic T cell cytokines and reducing NO generation,BA induces tissue-damaging ROS generation within CNS.

  15. Generating Multiple Alternative Clusterings Via Globally Optimal Subspaces

    DEFF Research Database (Denmark)

    Dang, Xuan-Hong; Bailey, James

    2014-01-01

    for alternative clustering generation. A distinctive feature of our algorithms is their principled formulation of an objective function, facilitating the discovery of a subspace satisfying natural quality and orthogonality criteria. The first algorithm is a regularization of the Principal Components analysis...

  16. Generating a Style-adaptive Trajectory from Multiple Demonstrations

    Directory of Open Access Journals (Sweden)

    Yue Zhao

    2014-07-01

    Full Text Available Trajectory learning and generation from demonstration have been widely discussed in recent years, with promising progress made. Existing approaches, including the Gaussian Mixture Model (GMM, affine functions and Dynamic Movement Primitives (DMPs have proven their applicability to learning the features and styles of existing trajectories and generating similar trajectories that can adapt to different dynamic situations. However, in many applications, such as grasping an object, shooting a ball, etc., different goals require trajectories of different styles. An issue that must be resolved is how to reproduce a trajectory with a suitable style. In this paper, we propose a style-adaptive trajectory generation approach based on DMPs, by which the style of the reproduced trajectories can change smoothly as the new goal changes. The proposed approach first adopts a Point Distribution Model (PDM to get the principal trajectories for different styles, then learns the model of each principal trajectory independently using DMPs, and finally adapts the parameters of the trajectory model smoothly according to the new goal using an adaptive goal-to-style mechanism. This paper further discusses the application of the approach on small-sized robots for an adaptive shooting task and on a humanoid robot arm to generate motions for table tennis-playing with different styles.

  17. Multiple nuclear ortholog next generation sequencing phylogeny of Daucus

    Science.gov (United States)

    Next generation sequencing is helping to solve the data insufficiency problem hindering well-resolved dominant gene phylogenies. We used Roche 454 technology to obtain DNA sequences from 93 nuclear orthologs, dispersed throughout all linkage groups of Daucus. Of these 93 orthologs, ten were designed...

  18. Random Scenario Generation for a Multiple Target Tracking Environment Evaluation

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

    The paper presents a simulation study on the generation of a random scenario for the performance of track splitting algorithm on a digital signal processor.  Much of the previous work [1] was done on specific (deterministic) scenarios. One of the reasons for considering the specific scenarios...

  19. Internal and ancestral controls of cell-generation times

    Science.gov (United States)

    Kubitschek, H. E.

    1969-01-01

    Lateral and longitudinal correlations between related cells reveal associations between the generation times of cells for an intermediate period /three generations in bacteral cultures/. Generation times of progeny are influenced by nongenetic factors transmitted from their ancestors.

  20. Generating cartilage repair from pluripotent stem cells.

    Science.gov (United States)

    Cheng, Aixin; Hardingham, Timothy E; Kimber, Susan J

    2014-08-01

    The treatment of degeneration and injury of articular cartilage has been very challenging for scientists and surgeons. As an avascular and hypocellular tissue, cartilage has a very limited capacity for self-repair. Chondrocytes are the only cell type in cartilage, in which they are surrounded by the extracellular matrix that they secrete and assemble. Autologous chondrocyte implantation for cartilage defects has achieved good results, but the limited resources and complexity of the procedure have hindered wider application. Stem cells form an alternative to chondrocytes as a source of chondrogenic cells due to their ability to proliferate extensively while retaining the potential for differentiation. Adult stem cells such as mesenchymal stem cells have been differentiated into chondrocytes, but the limitations in their proliferative ability and the heterogeneous cell population hinder their adoption as a prime alternative source for generating chondrocytes. Human embryonic stem cells (hESCs) are attractive as candidates for cell replacement therapy because of their unlimited self-renewal and ability for differentiation into mesodermal derivatives as well as other lineages. In this review, we focus on current protocols for chondrogenic differentiation of ESCs, in particular the chemically defined culture system developed in our lab that could potentially be adapted for clinical application.

  1. Next generation communications satellites: multiple access and network studies

    Science.gov (United States)

    Meadows, H. E.; Schwartz, M.; Stern, T. E.; Ganguly, S.; Kraimeche, B.; Matsuo, K.; Gopal, I.

    1982-01-01

    Efficient resource allocation and network design for satellite systems serving heterogeneous user populations with large numbers of small direct-to-user Earth stations are discussed. Focus is on TDMA systems involving a high degree of frequency reuse by means of satellite-switched multiple beams (SSMB) with varying degrees of onboard processing. Algorithms for the efficient utilization of the satellite resources were developed. The effect of skewed traffic, overlapping beams and batched arrivals in packet-switched SSMB systems, integration of stream and bursty traffic, and optimal circuit scheduling in SSMB systems: performance bounds and computational complexity are discussed.

  2. ALGORITHM TO CHOOSE ENERGY GENERATION MULTIPLE ROLE STATION

    Directory of Open Access Journals (Sweden)

    Alexandru STĂNESCU

    2014-05-01

    Full Text Available This paper proposes an algorithm that is based on a complex analysis method that is used for choosing the configuration of a power station. The station generates electric energy and hydrogen, and serves a "green" highway. The elements that need to be considered are: energy efficiency, location, availability of primary energy sources in the area, investment cost, workforce, environmental impact, compatibility with existing systems, meantime between failure.

  3. Fast generation of multiple resolution instances of raster data sets

    DEFF Research Database (Denmark)

    Arge, Lars; Haverkort, Herman; Tsirogiannis, Constantinos

    2012-01-01

    of this problem. Given a raster G of √N × √N cells we first consider the problem of computing for every 2 ≤ μ ≤ √N a raster Gμ of √N/μ × √N/μ cells such that each cell of Gμ stores the average of the values of μ×μ cells of G. We describe an algorithm that solves this problem in (N) time when the handled data fit...... in the main memory of the computer. We also provide two algorithms that solve this problem in external memory, that is when the input raster is larger than the main memory. The first external algorithm is very easy to implement and requires O(sort(N)) data block transfers from/to the external memory......, and the second algorithm requires only O(scan(N)) transfers, where sort(N) and scan(N) are the number of transfers needed to sort and scan N elements, respectively. We also study a variant of the problem where instead of the full input raster we handle only a connected subregion of arbitrary shape...

  4. Multiple quantum wells for passive ultra short laser pulse generation

    CERN Document Server

    Quintero-Torres, R; Rodriguez-Rodriguez, E; Stintz, Andreas; Diels, Jean-Claude

    2007-01-01

    Solid state lasers are demanding independent control in the gain media and cavity loss to achieve ultra short laser pulses using passive mode-locking. Recently, laser mode-locking is achieved with a MBE structure with multiple quantum wells, designed to achieve two functions; Bragg mirror and changes in absorption to control the cavity dynamics. The use of an AlGaAs/AlAs Bragg mirror with a 15 nm GaAs saturable absorber used in a Cr:LiSAF tuneable laser proved to be effective to produce femtosecond pulses. The use of saturable absorbers thus far is a trial and error procedure that is changing due to the correlation with more predictive procedures.

  5. Generation of mature hematopoietic cells from human pluripotent stem cells.

    Science.gov (United States)

    Togarrati, Padma Priya; Suknuntha, Kran

    2012-06-01

    A number of malignant and non-malignant hematological disorders are associated with the abnormal production of mature blood cells or primitive hematopoietic precursors. Their capacity for continuous self-renewal without loss of pluripotency and the ability to differentiate into adult cell types from all three primitive germ layers make human embryonic stem cells and induced pluripotent stem cells (hiPSCs) attractive complementary cell sources for large-scale production of transfusable mature blood cell components in cell replacement therapies. The generation of patient-specific hematopoietic stem/precursor cells from iPSCs by the regulated manipulation of various factors involved in reprograming to ensure complete pluripotency, and developing innovative differentiation strategies for generating unlimited supply of clinically safe, transplantable, HLA-matched cells from hiPSCs to outnumber the inadequate source of hematopoietic stem cells obtained from cord blood, bone marrow and peripheral blood, would have a major impact on the field of regenerative and personalized medicine leading to translation of these results from bench to bedside.

  6. A versatile method to generate multiple types of micropatterns

    CERN Document Server

    Segerer, F J; Schuster, S; Alberola, A Piera; Zahler, S; Rädler, J O

    2015-01-01

    Micropatterning techniques have become an important tool for the study of cell behavior in controlled microenvironments. As a consequence, several approaches for the creation of micropatterns have been developed in recent years. However, the diversity of substrates, coatings and complex patterns used in cell science is so great that no single existing technique is capable of fabricating designs suitable for all experimental conditions. Hence, there is a need for patterning protocols that are flexible with regard to the materials used and compatible with different patterning strategies to create more elaborate setups. In this work, we present a novel and versatile approach to micropatterning. The protocol is based on plasma treatment, protein coating, and a PLL-PEG backfill step, and produces homogeneous patterns on a variety of substrates. Protein density within the patterns can be controlled, and gradients of surface-bound protein can be formed. Moreover, by combining the method with microcontact printing, i...

  7. Cell-based reparative therapies for multiple sclerosis.

    Science.gov (United States)

    Ben-Hur, Tamir; Fainstein, Nina; Nishri, Yossi

    2013-11-01

    The strong rationale for cell-based therapy in multiple sclerosis is based on the ability of stem and precursor cells of neural and mesenchymal origin to attenuate neuroinflammation, to facilitate endogenous repair processes, and to participate directly in remyelination, if directed towards a myelin-forming fate. However, there are still major gaps in knowledge regarding induction of repair in chronic multiple sclerosis lesions, and whether transplanted cells can overcome the multiple environmental inhibitory factors which underlie the failure of endogenous repair. Major challenges in clinical translation include the determination of the optimal cellular platform, the route of cell delivery, and candidate patients for treatment.

  8. Suppression of multiple ion bunches and generation of monoenergetic ion beams in laser foil-plasma

    Institute of Scientific and Technical Information of China (English)

    Zhang Shan; Xie Bai-Song; Hong Xue-Ren; Wu Hai-Cheng; Aimierding Aimidula; Zhao Xue-Yan; Liu Ming-Ping

    2011-01-01

    In one-dimensional particle-in-cell simulations, this paper shows that the formation of multiple ion bunches is disadvantageous to the generation of monoenergetic ion beams and can be suppressed by choosing an optimum target thickness in the radiation pressure acceleration mechanism by a circularly polarised laser pulse. As the laser pulse becomes intense, the optimum target thickness obtained by a non-relativistic treatment is no longer adequate. Considering the relativistic Doppler-shifted pressure, it proposes a relativistic formulation to determine the optimum target thickness. The theoretical predictions agree with the simulation results well. The model is also valid for two-dimensional cases. The accelerated ion beams can be compelled to be more stable by choosing the optimum target thickness when they exhibit some unstable behaviours.

  9. Generating a transgenic mouse line stably expressing human MHC surface antigen from a HAC carrying multiple genomic BACs.

    Science.gov (United States)

    Hasegawa, Yoshinori; Ishikura, Tomoyuki; Hasegawa, Takanori; Watanabe, Takashi; Suzuki, Junpei; Nakayama, Manabu; Okamura, Yoshiaki; Okazaki, Tuneko; Koseki, Haruhiko; Ohara, Osamu; Ikeno, Masashi; Masumoto, Hiroshi

    2015-03-01

    The human artificial chromosome (HAC) vector is a promising tool to improve the problematic suppression and position effects of transgene expression frequently seen in transgenic cells and animals produced by conventional plasmid or viral vectors. We generated transgenic mice maintaining a single HAC vector carrying two genomic bacterial artificial chromosomes (BACs) from human HLA-DR loci (DRA and DRB1). Both transgenes on the HAC in transgenic mice exhibited tissue-specific expression in kidney, liver, lung, spleen, lymph node, bone marrow, and thymus cells in RT-PCR analysis. Stable functional expression of a cell surface HLA-DR marker from both transgenes, DRA and DRB1 on the HAC, was detected by flow cytometric analysis of splenocytes and maintained through at least eight filial generations. These results indicate that the de novo HAC system can allow us to manipulate multiple BAC transgenes with coordinated expression as a surface antigen through the generation of transgenic animals.

  10. Multiple forms of atypical rearrangements generating supernumerary derivative chromosome 15

    Directory of Open Access Journals (Sweden)

    Sigman Marian

    2008-01-01

    Full Text Available Abstract Background Maternally-derived duplications that include the imprinted region on the proximal long arm of chromosome 15 underlie a complex neurobehavioral disorder characterized by cognitive impairment, seizures and a substantial risk for autism spectrum disorders1. The duplications most often take the form of a supernumerary pseudodicentric derivative chromosome 15 [der(15] that has been called inverted duplication 15 or isodicentric 15 [idic(15], although interstitial rearrangements also occur. Similar to the deletions found in most cases of Angelman and Prader Willi syndrome, the duplications appear to be mediated by unequal homologous recombination involving low copy repeats (LCR that are found clustered in the region. Five recurrent breakpoints have been described in most cases of segmental aneuploidy of chromosome 15q11-q13 and previous studies have shown that most idic(15 chromosomes arise through BP3:BP3 or BP4:BP5 recombination events. Results Here we describe four duplication chromosomes that show evidence of atypical recombination events that involve regions outside the common breakpoints. Additionally, in one patient with a mosaic complex der(15, we examined homologous pairing of chromosome 15q11-q13 alleles by FISH in a region of frontal cortex, which identified mosaicism in this tissue and also demonstrated pairing of the signals from the der(15 and the normal homologues. Conclusion Involvement of atypical BP in the generation of idic(15 chromosomes can lead to considerable structural heterogeneity.

  11. Multiple Curricula for B Cell Developmental Programming.

    Science.gov (United States)

    Rothenberg, Ellen V

    2016-09-20

    B-1 B cells differ from conventional B-2 B cells functionally, but how these differences relate to the ontogeny of these lineages has been unclear. Two recent Immunity articles, Kristiansen et al. (2016) and Montecino-Rodriguez et al. (2016), now provide insight into the origins of B-1 and B-2 B cells, revealing a multi-layered developmental program and successive waves of B cell precursors.

  12. Optical cell sorting with multiple imaging modalities

    DEFF Research Database (Denmark)

    Banas, Andrew; Carrissemoux, Caro; Palima, Darwin

    2017-01-01

    techniques. Scattering forces from beams actuated via efficient phase-only efficient modulation has been adopted. This has lowered the required power for sorting cells to a tenth of our previous approach, and also makes the cell sorter safer for use in clinical settings. With the versatility of dynamically...... programmable phase spatial light modulators, a plurality of light shaping techniques, including hybrid approaches, can be utilized in cell sorting....... healthy cells. With the richness of visual information, a lot of microscopy techniques have been developed and have been crucial in biological studies. To utilize their complementary advantages we adopt both fluorescence and brightfield imaging in our optical cell sorter. Brightfield imaging has...

  13. Synthesis of Voltages of Multiple Uniform PWM, Generated by Trapezoidal and Sinusoidal Functions

    Directory of Open Access Journals (Sweden)

    A. Ctryzhniou

    2013-01-01

    Full Text Available The problem of synthesis and qualitative estimation of the harmonic composition of voltages of multiple uniform PWM pulses generated by trapezoidal and sinusoidal functions is considered. Analytical expressions for PWM pulses parameters ai  and ti have been received and they can be used for program-based generation of multiple uniform PWM, determination of n-harmonic magnitude in pulse-width regulation and AC motor operation simulation.

  14. Generation of human induced pluripotent stem cells from dermal fibroblasts

    OpenAIRE

    2008-01-01

    The generation of patient-specific pluripotent stem cells has the potential to accelerate the implementation of stem cells for clinical treatment of degenerative diseases. Technologies including somatic cell nuclear transfer and cell fusion might generate such cells but are hindered by issues that might prevent them from being used clinically. Here, we describe methods to use dermal fibroblasts easily obtained from an individual human to generate human induced pluripotent stem (iPS) cells by ...

  15. A patient with Multiple myeloma and Renal cell carcinoma.

    Science.gov (United States)

    Shahi, Farhad; Ghalamkari, Marziye; Mirzania, Mehrzad; Khatuni, Mahdi

    2016-01-01

    The coexistence of two malignancies is rarely seen. A little association between hematologic malignancies especially multiple myeloma and renal cell carcinoma has been reported in the recent past. Several case series revealed a bidirectional association between these two malignancies which may be due to the common risk factors, similar cytokine growth requirements and clinical presentation. Here, we aim to describe a patient who had multiple myeloma and in his work up renal cell carcinoma was found out incidentally. We would like to create awareness among clinicians for the coincidence of Renal cell carcinoma and Multiple myeloma.

  16. Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation

    DEFF Research Database (Denmark)

    Thrane, Jens F; Sunde, Niels A; Bergholt, Bo

    2014-01-01

    Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation......Increasing infection rate in multiple implanted pulse generator changes in movement disorder patients treated with deep brain stimulation...

  17. Multiple wavelength generation using a compacted hybrid Raman / Bi-EDF amplifier

    Directory of Open Access Journals (Sweden)

    Shirazi M. R.

    2013-05-01

    Full Text Available A multiple wavelength laser source is generated by a Brillouin seed signal and a compacted hybrid Raman / bismuth-based erbium doped fiber amplifier (Bi-EDFA in a linear cavity. The gain media of the Raman/Bi-EDFA is only a 2.15 m Bi-EDF pumped bi-directionally by two laser diodes (LDs. In comparison to all of the conventional multiple wavelength sources generated via using the same Bi-EDF and LDs, the proposed multiple wavelength source has much more number of lines due to using Raman and EDF amplification.

  18. Sufficient conditions for the additivity of stall forces generated by multiple filaments or motors

    Science.gov (United States)

    Bameta, Tripti; Das, Dipjyoti; Das, Dibyendu; Padinhateeri, Ranjith; Inamdar, Mandar M.

    2017-02-01

    Molecular motors and cytoskeletal filaments work collectively most of the time under opposing forces. This opposing force may be due to cargo carried by motors or resistance coming from the cell membrane pressing against the cytoskeletal filaments. Some recent studies have shown that the collective maximum force (stall force) generated by multiple cytoskeletal filaments or molecular motors may not always be just a simple sum of the stall forces of the individual filaments or motors. To understand this excess or deficit in the collective force, we study a broad class of models of both cytoskeletal filaments and molecular motors. We argue that the stall force generated by a group of filaments or motors is additive, that is, the stall force of N number of filaments (motors) is N times the stall force of one filament (motor), when the system is reversible at stall. Conversely, we show that this additive property typically does not hold true when the system is irreversible at stall. We thus present a novel and unified understanding of the existing models exhibiting such non-addivity, and generalise our arguments by developing new models that demonstrate this phenomena. We also propose a quantity similar to thermodynamic efficiency to easily predict this deviation from stall-force additivity for filament and motor collectives.

  19. 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.

  20. Automatic Mesh Generation of Hybrid Mesh on Valves in Multiple Positions in Feedline Systems

    Science.gov (United States)

    Ross, Douglass H.; Ito, Yasushi; Dorothy, Fredric W.; Shih, Alan M.; Peugeot, John

    2010-01-01

    Fluid flow simulations through a valve often require evaluation of the valve in multiple opening positions. A mesh has to be generated for the valve for each position and compounding. The problem is the fact that the valve is typically part of a larger feedline system. In this paper, we propose to develop a system to create meshes for feedline systems with parametrically controlled valve openings. Herein we outline two approaches to generate the meshes for a valve in a feedline system at multiple positions. There are two issues that must be addressed. The first is the creation of the mesh on the valve for multiple positions. The second is the generation of the mesh for the total feedline system including the valve. For generation of the mesh on the valve, we will describe the use of topology matching and mesh generation parameter transfer. For generation of the total feedline system, we will describe two solutions that we have implemented. In both cases the valve is treated as a component in the feedline system. In the first method the geometry of the valve in the feedline system is replaced with a valve at a different opening position. Geometry is created to connect the valve to the feedline system. Then topology for the valve is created and the portion of the topology for the valve is topology matched to the standard valve in a different position. The mesh generation parameters are transferred and then the volume mesh for the whole feedline system is generated. The second method enables the user to generate the volume mesh on the valve in multiple open positions external to the feedline system, to insert it into the volume mesh of the feedline system, and to reduce the amount of computer time required for mesh generation because only two small volume meshes connecting the valve to the feedline mesh need to be updated.

  1. Red blood cells and thrombin generation in sickle cell disease.

    Science.gov (United States)

    Whelihan, Matthew F; Lim, Ming Y; Key, Nigel S

    2014-05-01

    The prothrombotic nature of sickle cell disease (SCD) is evidenced by the chronically elevated levels of almost all coagulation activation biomarkers, and an increased incidence of certain thrombotic events, including venous thromboembolism. Numerous studies have attempted to define the extent and elucidate the mechanism of the observed increase in thrombin generation in SCD patients in vivo. In general, these studies were performed using thrombin generation assays in platelet poor or platelet rich plasma and showed little difference in endogenous thrombin potential between the SCD cohort and healthy matched controls. In SCD, erythrocytes and monocytes have been demonstrated to exhibit procoagulant characteristics. Thus, the absence of these cellular components in standard thrombin generation assays may fail to reflect global hypercoagulability in the whole blood of patients with SCD. We were therefore surprised to see no difference in net thrombin generation in tissue factor-initiated initiated clotting of whole blood from patients with SCD. However, we are continuing to reconcile these seemingly disparate observations by slight modifications of the whole blood model that include alternative coagulation triggers and a re-examination of the net thrombin generation when the protein/protein S system is simultaneously interrogated.

  2. The Role of Regulatory T Cells and TH17 Cells in Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Walter M. T. Braga

    2012-01-01

    Full Text Available The development of multiple myeloma (MM involves a series of genetic alterations and changes in the bone marrow microenvironment, favoring the growth of the tumor and failure of local immune control. Quantitative and functional alterations in CD4+ and CD8+ T cells have been described in MM. The balance between T regulatory cells (Treg and T helper (Th 17 cells represents one essential prerequisite for maintaining anti-tumor immunity in MM. Tregs play an important role in the preservation of self-tolerance and modulation of overall immune responses against infections and tumor cells. In MM patients, Tregs seem to contribute to myeloma-related immune dysfunction and targeting them could, therefore, help to restore and enhance vital immune responses. Th17 cells protect against fungal and parasitic infections and participate in inflammatory reactions and autoimmunity. The interplay of TGF-β and IL-6, expressed at high levels in the bone marrow of myeloma patients, may affect generation of Th17 cells both directly or via other pro-inflammatory cytokines and thereby modulate antitumor immune responses. A detailed analysis of the balance between Tregs and Th17 cells seems necessary in order to design more effective and less toxic modes of immunotherapy myeloma which still is an uncurable malignancy.

  3. Multiple skin tumors of indeterminate cells in an adult.

    Science.gov (United States)

    Kolde, G; Bröcker, E B

    1986-10-01

    An adult patient with multiple unusual histiocytic tumors of the skin is described. As shown by immunohistologic study, electron microscopy, and immunoelectron microscopy, the tumors represent circumscribed proliferations of the Langerhans cell-related indeterminate dendritic cells of the skin. This distinct cutaneous histiocytosis may represent a paraneoplastic syndrome.

  4. Variable Speed Wind Turbine Based on Multiple Generators Drive-Train Configuration

    DEFF Research Database (Denmark)

    Deng, Fujin; Chen, Zhe

    2010-01-01

    A variable speed wind turbine is presented in this paper, where multiple permanent magnet synchronous generators (MPMSGs) drive-train configuration is employed in the wind turbine. A cascaded multilevel converter interface based on the MPMSGs is developed to synthesize a desired high ac sinusoidal...... output voltage, which could be directly connected to the grids. What is more, such arrangement has been made so that the output ac voltage having a selected phase angle difference among the stator windings of multiple generators. A phase angle shift strategy is proposed in this paper, which effectively...... reduce the fluctuation of the electromagnetic torque sum and results in a good performance for the MPMSGs structure. The simulation study is conducted using PSCAD/EMTDC, and the results verify the feasibility of this variable speed wind turbine based on multiple generators drive-train configuration....

  5. Generation of induced pluripotent stem cells from human nasal epithelial cells using a Sendai virus vector.

    Directory of Open Access Journals (Sweden)

    Mizuho Ono

    Full Text Available The generation of induced pluripotent stem cells (iPSCs by introducing reprogramming factors into somatic cells is a promising method for stem cell therapy in regenerative medicine. Therefore, it is desirable to develop a minimally invasive simple method to create iPSCs. In this study, we generated human nasal epithelial cells (HNECs-derived iPSCs by gene transduction with Sendai virus (SeV vectors. HNECs can be obtained from subjects in a noninvasive manner, without anesthesia or biopsy. In addition, SeV carries no risk of altering the host genome, which provides an additional level of safety during generation of human iPSCs. The multiplicity of SeV infection ranged from 3 to 4, and the reprogramming efficiency of HNECs was 0.08-0.10%. iPSCs derived from HNECs had global gene expression profiles and epigenetic states consistent with those of human embryonic stem cells. The ease with which HNECs can be obtained, together with their robust reprogramming characteristics, will provide opportunities to investigate disease pathogenesis and molecular mechanisms in vitro, using cells with particular genotypes.

  6. Generation of Induced Pluripotent Stem Cells from Human Nasal Epithelial Cells Using a Sendai Virus Vector

    Science.gov (United States)

    Ono, Mizuho; Hamada, Yuko; Horiuchi, Yasue; Matsuo-Takasaki, Mami; Imoto, Yoshimasa; Satomi, Kaishi; Arinami, Tadao; Hasegawa, Mamoru; Fujioka, Tsuyoshi; Nakamura, Yukio; Noguchi, Emiko

    2012-01-01

    The generation of induced pluripotent stem cells (iPSCs) by introducing reprogramming factors into somatic cells is a promising method for stem cell therapy in regenerative medicine. Therefore, it is desirable to develop a minimally invasive simple method to create iPSCs. In this study, we generated human nasal epithelial cells (HNECs)-derived iPSCs by gene transduction with Sendai virus (SeV) vectors. HNECs can be obtained from subjects in a noninvasive manner, without anesthesia or biopsy. In addition, SeV carries no risk of altering the host genome, which provides an additional level of safety during generation of human iPSCs. The multiplicity of SeV infection ranged from 3 to 4, and the reprogramming efficiency of HNECs was 0.08–0.10%. iPSCs derived from HNECs had global gene expression profiles and epigenetic states consistent with those of human embryonic stem cells. The ease with which HNECs can be obtained, together with their robust reprogramming characteristics, will provide opportunities to investigate disease pathogenesis and molecular mechanisms in vitro, using cells with particular genotypes. PMID:22912751

  7. CO-GENERATION AND OPERATING NETWORK CELLS

    DEFF Research Database (Denmark)

    Nielsen, John Eli

    2008-01-01

    In Denmark several thousands of generators are connected to the distribution system (10 kV and 0.4 kV). The production from these generators many times exceeds the load. The generators can be divided into two types, Wind turbines and CHP generators. These generators have one thing in common......, the power system they are connected to, has never been designed to accommodate so many generators. In Denmark we now expect a third type of generators: the microgenerators. This time we want to be prepared. Denmark therefore now participates in a lot of research and full scale demonstration projects. A key...

  8. Fucoidan inhibits angiogenesis induced by multiple myeloma cells.

    Science.gov (United States)

    Liu, Fen; Luo, Guoping; Xiao, Qing; Chen, Liping; Luo, Xiaohua; Lv, Jinglong; Chen, Lixue

    2016-10-01

    Multiple myeloma (MM) remains an incurable hematological neoplasms. Our previous studies showed that Fucoidan possessed anti-myeloma effect by inducing apoptosis and inhibiting invasion of myeloma cells. In this study, we evaluated the effect of Fucoidan on angiogenesis induced by human myeloma cells and elucidated its possible mechanisms. Multiple myeloma cells were treated with Fucoidan at different concentrations, then the conditioned medium (CM) was collected. The levels of VEGF in the CM were tested by ELISA. The results showed that Fucoidan significantly decreased VEGF secretion by RPMI-8226 and U266 cells. The tube formation assay and migration test on human umbilical vein endothelial cells (HUVECs) were used to examine the effect of Fucoidan on angiogenesis induced by human myeloma cells. The results showed that Fucoidan decreased HUVECs formed tube structures and inhibited HUVECs migration, and suppressed the angiogenic ability of multiple myeloma RPMI-8226 and U266 cells in a dose-dependent manner. The study also showed that Fucoidan downregulated the expression of several kinds of proteins, which may be correlated with the reduction of angiogenesis induced by myeloma cells. Moreover, results were compared from normoxic and hypoxic conditions, they showed that Fucoidan had anti-angiogenic activity. Furthermore, in a multiple myeloma xenograft mouse model, it indicated that Fucoidan negatively affected tumor growth and angiogenesis in vivo. In conclusion, our results demonstrate that Fucoidan was able to interfere with angiogenesis of multiple myeloma cells both in vitro and in vivo and may have a substantial potential in the treatment of MM.

  9. AC power generation from microbial fuel cells

    Science.gov (United States)

    Lobo, Fernanda Leite; Wang, Heming; Forrestal, Casey; Ren, Zhiyong Jason

    2015-11-01

    Microbial fuel cells (MFCs) directly convert biodegradable substrates to electricity and carry good potential for energy-positive wastewater treatment. However, the low and direct current (DC) output from MFC is not usable for general electronics except small sensors, yet commercial DC-AC converters or inverters used in solar systems cannot be directly applied to MFCs. This study presents a new DC-AC converter system for MFCs that can generate alternating voltage in any desired frequency. Results show that AC power can be easily achieved in three different frequencies tested (1, 10, 60 Hz), and no energy storage layer such as capacitors was needed. The DC-AC converter efficiency was higher than 95% when powered by either individual MFCs or simple MFC stacks. Total harmonic distortion (THD) was used to investigate the quality of the energy, and it showed that the energy could be directly usable for linear electronic loads. This study shows that through electrical conversion MFCs can be potentially used in household electronics for decentralized off-grid communities.

  10. Hot exciton cooling and multiple exciton generation in PbSe quantum dots.

    Science.gov (United States)

    Kumar, Manoj; Vezzoli, Stefano; Wang, Zilong; Chaudhary, Varun; Ramanujan, Raju V; Gurzadyan, Gagik G; Bruno, Annalisa; Soci, Cesare

    2016-11-16

    Multiple exciton generation (MEG) is a promising process to improve the power conversion efficiency of solar cells. PbSe quantum dots (QDs) have shown reasonably high MEG quantum yield (QY), although the photon energy threshold for this process is still under debate. One of the reasons for this inconsistency is the complicated competition of MEG and hot exciton cooling, especially at higher excited states. Here, we investigate MEG QY and the origin of the photon energy threshold for MEG in PbSe QDs of three different sizes by studying the transient absorption (TA) spectra, both at the band gap (near infrared, NIR) and far from the band gap energy (visible range). The comparison of visible TA spectra and dynamics for different pump wavelengths, below, around and above the MEG threshold, provides evidence of the role of the Σ transition in slowing down the exciton cooling process that can help MEG to take over the phonon relaxation process. The universality of this behavior is confirmed by studying QDs of three different sizes. Moreover, our results suggest that MEG QY can be determined by pump-probe experiments probed above the band gap.

  11. Alpha-particles induce autophagy in multiple myeloma cells

    Directory of Open Access Journals (Sweden)

    Joelle Marcelle Gaschet

    2015-10-01

    Full Text Available Objectives: Radiations emitted by the radionuclides in radioimmunotherapy (RIT approaches induce direct killing of the targeted cells as well as indirect killing through bystander effect. Our research group is dedicated to the development of α-RIT, i.e RIT using α-particles especially for the treatment of multiple myeloma (MM. γ-irradiation and β-irradiation have been shown to trigger apoptosis in tumor cells. Cell death mode induced by 213Bi α-irradiation appears more controversial. We therefore decided to investigate the effects of 213Bi on MM cell radiobiology, notably cell death mechanisms as well as tumor cell immunogenicity after irradiation.Methods: Murine 5T33 and human LP-1 multiple myeloma (MM cell lines were used to study the effects of such α-particles. We first examined the effects of 213Bi on proliferation rate, double strand DNA breaks, cell cycle and cell death. Then, we investigated autophagy after 213Bi irradiation. Finally, a co-culture of dendritic cells (DC with irradiated tumour cells or their culture media was performed to test whether it would induce DC activation.Results: We showed that 213Bi induces DNA double strand breaks, cell cycle arrest and autophagy in both cell lines but we detected only slight levels of early apoptosis within the 120 hours following irradiation in 5T33 and LP-1. Inhibition of autophagy prevented 213Bi induced inhibition of proliferation in LP-1 suggesting that this mechanism is involved in cell death after irradiation. We then assessed the immunogenicity of irradiated cells and found that irradiated LP-1 can activate DC through the secretion of soluble factor(s, however no increase in membrane or extracellular expression of danger associated molecular patterns (DAMPs was observed after irradiation.Conclusion: This study demonstrates that 213Bi induces mainly necrosis in MM cells, low levels of apoptosis and also autophagy that might be involved in tumor cell death.

  12. Multiple metastatic renal cell carcinoma isolated to pancreas.

    Science.gov (United States)

    Comunoğlu, Cem; Altaca, Gülüm; Demiralay, Ebru; Moray, Gökhan

    2012-06-01

    Renal cell carcinoma (RCC) metastases to the pancreas are reported to be rare. Isolated multiple pancreatic metastases are even rarer. We report a 68-year-old asymptomatic male patient who presented with multiple metastatic nodular lesions in the pancreas demonstrated by computerized tomography 3.5 years after radical nephrectomy performed for clear cell RCC. Spleen-preserving total pancreatectomy was performed. Gross examination revealed five well-demarcated tumoral nodules in the head, body and tail of the pancreas. Histopathological examination revealed clusters of epithelial clear cells, immunohistochemically positive for CD10 and vimentin, and negative for CK19 and chromogranin, supporting a diagnosis of metastatic RCC. The patient has remained well at 29 months post-resection, in agreement with recent experience that radical resection for multiple isolated metastatic nodular lesions can achieve improved survival and better quality of life.

  13. Squamous cell carcinoma arising in a multiple verrucous epidermal nevus*

    Science.gov (United States)

    Yarak, Samira; Machado, Taila Yuri Siqueira; Ogawa, Marilia Marufuji; Almeida, Mirian Luzia da Silva; Enokihara, Milvia Maria Simões e Silva; Porro, Adriana Maria

    2016-01-01

    Verrucous epidermal nevi are hamartomatous lesions of the epidermis that, unlike other epidermal nevi (such as sebaceous nevus or nevus comedonicus), are rarely associated with malignant neoplasms. The majority of squamous cell carcinoma develop in linear or multiple epidermal nevus and rarely in solitary epidermal nevus. In general, the prognosis is favorable. We report a case of well-differentiated invasive squamous cell carcinoma arising from a multiple verrucous epidermal nevus. Although there is no consensus on prophylactic removal of epidermal nevus, its removal and biopsy should be considered if changes occur. PMID:28300931

  14. A protease storm cleaves a cell-cell adhesion molecule in cancer: multiple proteases converge to regulate PTPmu in glioma cells.

    Science.gov (United States)

    Phillips-Mason, Polly J; Craig, Sonya E L; Brady-Kalnay, Susann M

    2014-09-01

    Cleavage of the cell-cell adhesion molecule, PTPµ, occurs in human glioblastoma multiforme brain tumor tissue and glioma cell lines. PTPµ cleavage is linked to increased cell motility and growth factor independent survival of glioma cells in vitro. Previously, PTPµ was shown to be cleaved by furin in the endoplasmic reticulum to generate membrane associated E- (extracellular) and P- (phosphatase) subunits, and by ADAMs and the gamma secretase complex at the plasma membrane. We also identified the presence of additional extracellular and intracellular PTPµ fragments in brain tumors. We set out to biochemically analyze PTPµ cleavage in cancer cells. We determined that, in addition to the furin-processed form of PTPµ, a pool of 200 kDa full-length PTPµ exists at the plasma membrane that is cleaved directly by ADAM to generate a larger shed form of the PTPµ extracellular segment. Notably, in glioma cells, full-length PTPµ is also subject to calpain cleavage, which generates novel PTPµ fragments not found in other immortalized cells. We also observed glycosylation and phosphorylation differences in the cancer cells. Our data suggest that an additional serine protease also contributes to PTPµ shedding in glioma cells. We hypothesize that a "protease storm" occurs in cancer cells whereby multiple proteases converge to reduce the presence of cell-cell adhesion molecules at the plasma membrane and to generate protein fragments with unique biological functions. As a consequence, the "protease storm" could promote the migration and invasion of tumor cells.

  15. C/EBPβ regulates transcription factors critical for proliferation and survival of multiple myeloma cells

    Science.gov (United States)

    Pal, Rekha; Janz, Martin; Galson, Deborah L.; Gries, Margarete; Li, Shirong; Jöhrens, Korinna; Anagnostopoulos, Ioannis; Dörken, Bernd; Mapara, Markus Y.; Borghesi, Lisa; Kardava, Lela; Roodman, G. David; Milcarek, Christine

    2009-01-01

    CCAAT/enhancer-binding protein β (C/EBPβ), also known as nuclear factor–interleukin-6 (NF-IL6), is a transcription factor that plays an important role in the regulation of growth and differentiation of myeloid and lymphoid cells. Mice deficient in C/EBPβ show impaired generation of B lymphocytes. We show that C/EBPβ regulates transcription factors critical for proliferation and survival in multiple myeloma. Multiple myeloma cell lines and primary multiple myeloma cells strongly expressed C/EBPβ, whereas normal B cells and plasma cells had little or no detectable levels of C/EBPβ. Silencing of C/EBPβ led to down-regulation of transcription factors such as IRF4, XBP1, and BLIMP1 accompanied by a strong inhibition of proliferation. Further, silencing of C/EBPβ led to a complete down-regulation of antiapoptotic B-cell lymphoma 2 (BCL2) expression. In chromatin immunoprecipitation assays, C/EBPβ directly bound to the promoter region of IRF4, BLIMP1, and BCL2. Our data indicate that C/EBPβ is involved in the regulatory network of transcription factors that are critical for plasma cell differentiation and survival. Targeting C/EBPβ may provide a novel therapeutic strategy in the treatment of multiple myeloma. PMID:19717648

  16. Generating Multiple Base-Resolution DNA Methylomes Using Reduced Representation Bisulfite Sequencing.

    Science.gov (United States)

    Chatterjee, Aniruddha; Rodger, Euan J; Stockwell, Peter A; Le Mée, Gwenn; Morison, Ian M

    2017-01-01

    Reduced representation bisulfite sequencing (RRBS) is an effective technique for profiling genome-wide DNA methylation patterns in eukaryotes. RRBS couples size selection, bisulfite conversion, and second-generation sequencing to enrich for CpG-dense regions of the genome. The progressive improvement of second-generation sequencing technologies and reduction in cost provided an opportunity to examine the DNA methylation patterns of multiple genomes. Here, we describe a protocol for sequencing multiple RRBS libraries in a single sequencing reaction to generate base-resolution methylomes. Furthermore, we provide a brief guideline for base-calling and data analysis of multiplexed RRBS libraries. These strategies will be useful to perform large-scale, genome-wide DNA methylation analysis.

  17. Note: High precision angle generator using multiple ultrasonic motors and a self-calibratable encoder

    Science.gov (United States)

    Kim, Jong-Ahn; Kim, Jae Wan; Kang, Chu-Shik; Jin, Jonghan; Bong Eom, Tae

    2011-11-01

    We present an angle generator with high resolution and accuracy, which uses multiple ultrasonic motors and a self-calibratable encoder. A cylindrical air bearing guides a rotational motion, and the ultrasonic motors achieve high resolution over the full circle range with a simple configuration. The self-calibratable encoder can compensate the scale error of a divided circle (signal period: 20″) effectively by applying the equal-division-averaged method. The angle generator configures a position feedback control loop using the readout of the encoder. By combining the ac and dc operation mode, the angle generator produced stepwise angular motion with 0.005″ resolution. We also evaluated the performance of the angle generator using a precision angle encoder and an autocollimator. The expanded uncertainty (k = 2) in the angle generation was estimated less than 0.03″, which included the calibrated scale error and the nonlinearity error.

  18. Inhibition of autophagy enhances apoptosis involved with intracellular ROS generation in multiple myeloma cells exposed to Oridonin%抑制自噬促进冬凌草甲素诱导的多发性骨髓瘤细胞凋亡涉及胞内ROS产生

    Institute of Scientific and Technical Information of China (English)

    曾蓉; 陈燕; 崔国惠

    2011-01-01

    目的 本实验主要研究冬凌草甲素诱导多发性骨髓瘤发生自噬、凋亡,两者之间的关系以及所涉及的相关机制.方法 利用MTT比色法检测冬凌草甲素对多发性骨髓瘤RPMI8226细胞的增殖活性影响;透视电镜观察细胞内凋亡和自噬的形态学改变;TUNEL检测细胞凋亡;分别利用以下技术检测处理后的细胞内的自噬变化:使用QDs605nm-Anti-LC3荧光探针以及免疫荧光技术定位细胞胞内LC3Ⅰ和LC3Ⅱ蛋白,利用western blot免疫印记技术检测Beclin 1蛋白表达水平;利用DCFH-DA探针以及流式细胞术检测细胞胞内ROS水平.结果 冬凌草甲素能明显抑制RPMI8226细胞增殖,其抑制作用呈时间、剂量依赖性;冬凌草甲素能同时诱发细胞凋亡、自噬和胞内ROS产生;NAC完全抑制胞内ROS产生后冬凌草甲素诱导的细胞凋亡消失;3-MA抑制自噬后,冬凌草甲素诱导的胞内ROS产生进一步增多,凋亡增多.结论 冬凌草甲素能明显抑制RPMI8226细胞增殖;冬凌草甲素同时诱发细胞凋亡和自噬;胞内ROS产生介导冬凌草甲素诱导的凋亡;凋亡为细胞死亡的主要途径,而自噬通过下调胞内ROS产生抑制凋亡.%Objective To explore the oridonin-induced apoptosis and autophagy of multiple myelomacells the relationship between them, and the involved molecular mechanisms. Methods RPM18226 cell vitality was assessed by MTT assay. The morphology of apoptosis and autophagy was observed by TEM.TUNEL assay was used to determine apoptosis. The LC3 localization and the Beclinl protein level indicating autophagy level were analyzed by immunofluorescence analysis using the QDs605nm-AntiLC3 fluorescent probe and western blot assay. The intracellular ROS generation was estimated by FCM using the uorescent probe DCFH-DA. Results Oridonin inhibited the proliferation of RPM18226 cells dose- and time-dependently. Oridonin simultaneously induced apoptosis, autophagy and intracellular ROS generation

  19. Cell multiplication following partial enzymatic removal of surface coat.

    Science.gov (United States)

    Wyroba, E

    1978-08-01

    Treatment of Paramecium aurelia with trypsin or pronase (1 mg per 10(5) cells, at 0 to 4 degrees C) partially removes the surface coat and modifies significantly multiplication of cells. The division rate after 24 hours of cultivation is diminished approximately twice in the case of pronase-treated cells and 1.5 for tyrpsin-digested ciliates as compared with the control. On the second day the division rate increases rapidly and number of cell divisions exceeds the values observed in the control. After 72 hours of cultivation the division rate in both untreated and enzyme-treated cells is almost the same. It is concluded that the observed inhibition of cell fission results from the enzymatic removal of the surface coat--the integrity of this surface coat seems to be necessary in the process of cell division. The influence of environmental factors on the rate of growth is presented.

  20. Multiple superficial basal cell carcinomas (basalomatosis) following cobalt irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Wollenberg, A.; Przybilla, B. [Muenchen Univ. (Germany). Dermatologische Klinik und Poliklinik; Peter, R.U. [Federal Armed Forces Medical Academy, Munich (Germany). Inst. of Radiobiology

    1995-10-01

    Basalomatosis is an uncommon skin condition characterized by the occurrence of multiple basal cell carcinomas. Many cases reported in the literature have been attributed to arsenic treatment in psoriasis patients. We report a patient with basalomatosis caused by cobalt-60 ({sup 60}Co) irradiation. A 55-year-old farmer developed 43 basal cell carcinomas 20 years after treatment of an immuno-blastoma with {sup 60}Co irradiation. All the tumours were located within the radiation fields. Other possible causes of basalomatosis, such as arsenic intoxication and basal cell naevus syndrome, were excluded. The patient`s multiple superficial basal cell carcinomas probably represent a late adverse effect of the {sup 60}Co irradiation. (Author).

  1. Hematopoietic specification from human pluripotent stem cells: current advances and challenges toward de novo generation of hematopoietic stem cells.

    Science.gov (United States)

    Slukvin, Igor I

    2013-12-12

    Significant advances in cellular reprogramming technologies and hematopoietic differentiation from human pluripotent stem cells (hPSCs) have already enabled the routine production of multiple lineages of blood cells in vitro and opened novel opportunities to study hematopoietic development, model genetic blood diseases, and manufacture immunologically matched cells for transfusion and cancer immunotherapy. However, the generation of hematopoietic cells with robust and sustained multilineage engraftment has not been achieved. Here, we highlight the recent advances in understanding the molecular and cellular pathways leading to blood development from hPSCs and discuss potential approaches that can be taken to facilitate the development of technologies for de novo production of hematopoietic stem cells.

  2. A method for generation of bone marrow-derived macrophages from cryopreserved mouse bone marrow cells.

    Directory of Open Access Journals (Sweden)

    Fernanda M Marim

    Full Text Available The broad use of transgenic and gene-targeted mice has established bone marrow-derived macrophages (BMDM as important mammalian host cells for investigation of the macrophages biology. Over the last decade, extensive research has been done to determine how to freeze and store viable hematopoietic human cells; however, there is no information regarding generation of BMDM from frozen murine bone marrow (BM cells. Here, we establish a highly efficient protocol to freeze murine BM cells and further generate BMDM. Cryopreserved murine BM cells maintain their potential for BMDM differentiation for more than 6 years. We compared BMDM obtained from fresh and frozen BM cells and found that both are similarly able to trigger the expression of CD80 and CD86 in response to LPS or infection with the intracellular bacteria Legionella pneumophila. Additionally, BMDM obtained from fresh or frozen BM cells equally restrict or support the intracellular multiplication of pathogens such as L. pneumophila and the protozoan parasite Leishmania (L. amazonensis. Although further investigation are required to support the use of the method for generation of dendritic cells, preliminary experiments indicate that bone marrow-derived dendritic cells can also be generated from cryopreserved BM cells. Overall, the method described and validated herein represents a technical advance as it allows ready and easy generation of BMDM from a stock of frozen BM cells.

  3. Multiplicity of Sites for Extrathymic T-cell Differentiation

    OpenAIRE

    Abo, Toru; Watanabe, Hisami; Sekikawa, Hiroho

    1993-01-01

    In addition to an intrathymic pathway of T-cell differentiation, extrathymic pathways of T-cell differentiation have been found to exist at multiple sites in the living bodies of both mice and humans. Such sites include the sinusoids in the liver, intraepithelial sites in the intestine, the splenic red pulp, the thymic medulla, the decidua in the uterus, and the omentum in the peritoneal cavity. Although extrathymic pathways are minimal in youth, they become predominant with aging and under c...

  4. Bortezomib consolidation after autologous stem cell transplantation in multiple myeloma

    DEFF Research Database (Denmark)

    Mellqvist, Ulf-Henrik; Gimsing, Peter; Hjertner, Oyvind

    2013-01-01

    The Nordic Myeloma Study Group conducted an open randomized trial to compare bortezomib as consolidation therapy given after high-dose therapy and autologous stem cell transplantation (ASCT) with no consolidation in bortezomib-naive patients with newly diagnosed multiple myeloma. Overall, 370...

  5. Generation of dendritic cells and macrophages from human induced pluripotent stem cells aiming at cell therapy.

    Science.gov (United States)

    Senju, S; Haruta, M; Matsumura, K; Matsunaga, Y; Fukushima, S; Ikeda, T; Takamatsu, K; Irie, A; Nishimura, Y

    2011-09-01

    This report describes generation of dendritic cells (DCs) and macrophages from human induced pluripotent stem (iPS) cells. iPS cell-derived DC (iPS-DC) exhibited the morphology of typical DC and function of T-cell stimulation and antigen presentation. iPS-DC loaded with cytomegalovirus (CMV) peptide induced vigorous expansion of CMV-specific autologous CD8+ T cells. Macrophages (iPS-MP) with activity of zymosan phagocytosis and C5a-induced chemotaxis were also generated from iPS cells. Genetically modified iPS-MPs were generated by the introduction of expression vectors into undifferentiated iPS cells, isolation of transfectant iPS cell clone and subsequent differentiation. By this procedure, we generated iPS-MP expressing a membrane-bound form of single chain antibody (scFv) specific to amyloid β (Aβ), the causal protein of Alzheimer's disease. The scFv-transfectant iPS-MP exhibited efficient Aβ-specific phagocytosis activity. iPS-MP expressing CD20-specific scFv engulfed and killed BALL-1 B-cell leukemia cells. Anti-BALL-1 effect of iPS-MP in vivo was demonstrated in a xeno-transplantation model using severe combined immunodeficient mice. In addition, we established a xeno-free culture protocol to generate iPS-DC and iPS-MP. Collectively, we demonstrated the possibility of application of iPS-DC and macrophages to cell therapy.

  6. Alemtuzumab treatment alters circulating innate immune cells in multiple sclerosis

    Science.gov (United States)

    Ahmetspahic, Diana; Ruck, Tobias; Schulte-Mecklenbeck, Andreas; Schwarte, Kathrin; Jörgens, Silke; Scheu, Stefanie; Windhagen, Susanne; Graefe, Bettina; Melzer, Nico; Klotz, Luisa; Arolt, Volker; Wiendl, Heinz; Meuth, Sven G.

    2016-01-01

    Objective: To characterize changes in myeloid and lymphoid innate immune cells in patients with relapsing-remitting multiple sclerosis (MS) during a 6-month follow-up after alemtuzumab treatment. Methods: Circulating innate immune cells including myeloid cells and innate lymphoid cells (ILCs) were analyzed before and 6 and 12 months after onset of alemtuzumab treatment. Furthermore, a potential effect on granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)–23 production by myeloid cells and natural killer (NK) cell cytolytic activity was determined. Results: In comparison to CD4+ T lymphocytes, myeloid and lymphoid innate cell subsets of patients with MS expressed significantly lower amounts of CD52 on their cell surface. Six months after CD52 depletion, numbers of circulating plasmacytoid dendritic cells (DCs) and conventional DCs were reduced compared to baseline. GM-CSF and IL-23 production in DCs remained unchanged. Within the ILC compartment, the subset of CD56bright NK cells specifically expanded under alemtuzumab treatment, but their cytolytic activity did not change. Conclusions: Our findings demonstrate that 6 months after alemtuzumab treatment, specific DC subsets are reduced, while CD56bright NK cells expanded in patients with MS. Thus, alemtuzumab specifically restricts the DC compartment and expands the CD56bright NK cell subset with potential immunoregulatory properties in MS. We suggest that remodeling of the innate immune compartment may promote long-term efficacy of alemtuzumab and preserve immunocompetence in patients with MS. PMID:27766281

  7. Optimal dynamic scheduling of a power generation system to satisfy multiple criteria

    DEFF Research Database (Denmark)

    Forouzbakhsh, Farshid; Deiters, Robert M.; Shoushtari Kermanshahi, Bahman

    1991-01-01

    A computer algorithm for the optimal scheduling of generators in a power system is presented and tested. The algorithm, based on goal programming, automatically and dynami cally schedules the output of each generator in the system for optimal operation. The optimal operation can take...... into consideration multiple objectives such as economy, security, and reduction of pollution as well as practical constraints. To validate and test the algorithm, an example system of 5 generators, 10 busses, and 11 transmission lines is optimized for two objectives: minimal generation cost and minimal emission...... of nitrous oxides (NOx). Hourly changes in total power demand in the range of 90% to 110% are considered together with a constraint of maximum permissible total NOx emission. Other practical equality and inequality constraints are incorporated into the optimization algorithm. The simulation results...

  8. New type of cells with multiple chromosome rearrangements

    Energy Technology Data Exchange (ETDEWEB)

    Aseeva, Elena A. [National Research Centre for Hematology, Russian Academy of Medical Sciences, Novozykovsky proezd 4a, 125167 Moscow (Russian Federation); Snigiryova, Galina P. [Russian Scientific Centre of Roentgenology and Radiology, ul. Profsoyuznaya 86, 117997 Moscow (Russian Federation); Neverova, Anna L. [National Research Centre for Hematology, Russian Academy of Medical Sciences, Novozykovsky proezd 4a, 125167 Moscow (Russian Federation); Bogomazova, Alexandra N.; Novitskaya, Natalia N.; Khazins, Eva D. [Russian Scientific Centre of Roentgenology and Radiology, ul. Profsoyuznaya 86, 117997 Moscow (Russian Federation); Domracheva, Elena V. [National Research Centre for Hematology, Russian Academy of Medical Sciences, Novozykovsky proezd 4a, 125167 Moscow (Russian Federation)], E-mail: dom@blood.ru

    2010-04-15

    A comparative analysis of the distribution and the frequency of multiaberrant cells (MAC) among lymphocytes in different categories of low dose (up to 0.5 Gy) irradiated people was carried out. The highest MAC frequency was observed in people exposed to {alpha}-radiation (Pu, Rn) and in cosmonauts. This fact allows MAC to be considered as an indicator of a high-energy local exposure. A new type of cells with multiple chromosome rearrangements was discovered in the course of analysis of stable aberrations by the fluorescence in situ hybridization (FISH) method. The biological consequences of MAC formation and possibility of revealing the whole diversity of cells with multiple aberrations by means of modern molecular-cytogenetic methods are discussed.

  9. Multiple jaw cysts not associated with basal cell nevus syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Suk Ja; Kang, Byung Cheol [Chonnam National University College of Medicine, Kwangju (Korea, Republic of)

    2003-09-15

    We present two cases of multiple jaw cysts not associated with basal cell nevus syndrome. Case 1 : a nine year-old boy visited CNU Hospital for orthodontic treatment and his radiographs showed cystic lesions surrounding the crowns of teeth 13 and 17 respectively, which were diagnosed as dentigerous cysts. Subsequently, two more cysts were found on his follow-up radiographs in 12 and 15 months. The two cysts were determined to be odontogenic keratocysts. The boy had no skeletal abnormalities and no skin lesions associated with basal cell nevus syndrome. Case 2: a fifty-eight year old man had three impacted third molars with pericoronal radiolucencies, which were diagnosed as dentigerous cysts. He had no additional abnormalities associated with basal cell nevus syndrome. Multiple jaw cysts can occur at any age, and periodic radiographic surveillance may be needed for any cases of impacted tooth.

  10. Probabilistic Inference on Multiple Normalized Signal Profiles from Next Generation Sequencing: Transcription Factor Binding Sites

    KAUST Repository

    Wong, Ka-Chun

    2015-04-20

    With the prevalence of chromatin immunoprecipitation (ChIP) with sequencing (ChIP-Seq) technology, massive ChIP-Seq data has been accumulated. The ChIP-Seq technology measures the genome-wide occupancy of DNA-binding proteins in vivo. It is well-known that different DNA-binding protein occupancies may result in a gene being regulated in different conditions (e.g. different cell types). To fully understand a gene\\'s function, it is essential to develop probabilistic models on multiple ChIP-Seq profiles for deciphering the gene transcription causalities. In this work, we propose and describe two probabilistic models. Assuming the conditional independence of different DNA-binding proteins\\' occupancies, the first method (SignalRanker) is developed as an intuitive method for ChIP-Seq genome-wide signal profile inference. Unfortunately, such an assumption may not always hold in some gene regulation cases. Thus, we propose and describe another method (FullSignalRanker) which does not make the conditional independence assumption. The proposed methods are compared with other existing methods on ENCODE ChIP-Seq datasets, demonstrating its regression and classification ability. The results suggest that FullSignalRanker is the best-performing method for recovering the signal ranks on the promoter and enhancer regions. In addition, FullSignalRanker is also the best-performing method for peak sequence classification. We envision that SignalRanker and FullSignalRanker will become important in the era of next generation sequencing. FullSignalRanker program is available on the following website: http://www.cs.toronto.edu/∼wkc/FullSignalRanker/ © 2015 IEEE.

  11. A hybrid procedure for MSW generation forecasting at multiple time scales in Xiamen City, China

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Lilai, E-mail: llxu@iue.ac.cn [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen 361021 (China); Xiamen Key Lab of Urban Metabolism, Xiamen 361021 (China); Gao, Peiqing, E-mail: peiqing15@yahoo.com.cn [Xiamen City Appearance and Environmental Sanitation Management Office, 51 Hexiangxi Road, Xiamen 361004 (China); Cui, Shenghui, E-mail: shcui@iue.ac.cn [Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, 1799 Jimei Road, Xiamen 361021 (China); Xiamen Key Lab of Urban Metabolism, Xiamen 361021 (China); Liu, Chun, E-mail: xmhwlc@yahoo.com.cn [Xiamen City Appearance and Environmental Sanitation Management Office, 51 Hexiangxi Road, Xiamen 361004 (China)

    2013-06-15

    Highlights: ► We propose a hybrid model that combines seasonal SARIMA model and grey system theory. ► The model is robust at multiple time scales with the anticipated accuracy. ► At month-scale, the SARIMA model shows good representation for monthly MSW generation. ► At medium-term time scale, grey relational analysis could yield the MSW generation. ► At long-term time scale, GM (1, 1) provides a basic scenario of MSW generation. - Abstract: Accurate forecasting of municipal solid waste (MSW) generation is crucial and fundamental for the planning, operation and optimization of any MSW management system. Comprehensive information on waste generation for month-scale, medium-term and long-term time scales is especially needed, considering the necessity of MSW management upgrade facing many developing countries. Several existing models are available but of little use in forecasting MSW generation at multiple time scales. The goal of this study is to propose a hybrid model that combines the seasonal autoregressive integrated moving average (SARIMA) model and grey system theory to forecast MSW generation at multiple time scales without needing to consider other variables such as demographics and socioeconomic factors. To demonstrate its applicability, a case study of Xiamen City, China was performed. Results show that the model is robust enough to fit and forecast seasonal and annual dynamics of MSW generation at month-scale, medium- and long-term time scales with the desired accuracy. In the month-scale, MSW generation in Xiamen City will peak at 132.2 thousand tonnes in July 2015 – 1.5 times the volume in July 2010. In the medium term, annual MSW generation will increase to 1518.1 thousand tonnes by 2015 at an average growth rate of 10%. In the long term, a large volume of MSW will be output annually and will increase to 2486.3 thousand tonnes by 2020 – 2.5 times the value for 2010. The hybrid model proposed in this paper can enable decision makers to

  12. A multiplicative process for generating the rank-order distribution of UK election results

    CERN Document Server

    Fenner, Trevor; Loizou, George

    2016-01-01

    Human dynamics and sociophysics suggest statistical models that may explain and provide us with a better understanding of social phenomena. Here we propose a generative multiplicative decrease model that gives rise to a rank-order distribution and allows us to analyse the results of the last three UK parliamentary elections. We provide empirical evidence that the additive Weibull distribution, which can be generated from our model, is a close fit to the electoral data, offering a novel interpretation of the recent election results.

  13. Robust generation of high-fidelity entangled states for multiple atoms

    Institute of Scientific and Technical Information of China (English)

    Lin Li-Hua

    2009-01-01

    A scheme is presented for generating entangled states of multiple atoms in a cavity. In the scheme the atoms simultaneously interact with a cavity mode, with the first atom driven by two classical fields and the other atoms driven by a classical field. Our scheme is valid even if the cavity decay rate is larger than the effective coupling strength, which is important for experiment. The generation of entangled states is conditional on the detection of a photon decaying from the cavity and thus the fidelity of the entangled state is insensitive to the detection inefficiency. Furthermore, the scheme can be applied to the case with any number of atoms in principle.

  14. Analysis of dynamic behavior of multiple-stage planetary gear train used in wind driven generator.

    Science.gov (United States)

    Wang, Jungang; Wang, Yong; Huo, Zhipu

    2014-01-01

    A dynamic model of multiple-stage planetary gear train composed of a two-stage planetary gear train and a one-stage parallel axis gear is proposed to be used in wind driven generator to analyze the influence of revolution speed and mesh error on dynamic load sharing characteristic based on the lumped parameter theory. Dynamic equation of the model is solved using numerical method to analyze the uniform load distribution of the system. It is shown that the load sharing property of the system is significantly affected by mesh error and rotational speed; load sharing coefficient and change rate of internal and external meshing of the system are of obvious difference from each other. The study provides useful theoretical guideline for the design of the multiple-stage planetary gear train of wind driven generator.

  15. Analysis of Dynamic Behavior of Multiple-Stage Planetary Gear Train Used in Wind Driven Generator

    Directory of Open Access Journals (Sweden)

    Jungang Wang

    2014-01-01

    Full Text Available A dynamic model of multiple-stage planetary gear train composed of a two-stage planetary gear train and a one-stage parallel axis gear is proposed to be used in wind driven generator to analyze the influence of revolution speed and mesh error on dynamic load sharing characteristic based on the lumped parameter theory. Dynamic equation of the model is solved using numerical method to analyze the uniform load distribution of the system. It is shown that the load sharing property of the system is significantly affected by mesh error and rotational speed; load sharing coefficient and change rate of internal and external meshing of the system are of obvious difference from each other. The study provides useful theoretical guideline for the design of the multiple-stage planetary gear train of wind driven generator.

  16. Image encryption combining multiple generating sequences controlled fractional DCT with dependent scrambling and diffusion

    Science.gov (United States)

    Liang, Yaru; Liu, Guoping; Zhou, Nanrun; Wu, Jianhua

    2015-02-01

    Based on the fractional discrete cosine transform with multiple generating sequences (MGSFrDCT) and the dependent scrambling and diffusion (DSD), an image encryption algorithm is proposed, in which the multiple-generating sequences greatly enlarge the key space of the encryption system. The real-valued output of MGSFrDCT is beneficial to storage, display and transmission of the cipher-text. During the stage of confusion and diffusion, the locations and values of all MGSFrDCT transformed coefficients change due to DSD, and the initial values and fractional orders of encryption system depend not only on the cipher keys but also on the plain-image due to introduction of a disturbance factor, which allows the encryption system to resist the known-plaintext and chosen-plaintext attacks. Experimental results demonstrate that the proposed encryption algorithm is feasible, effective and secure and able to resist common classical attacks.

  17. A Statistical Evaluation of Multiplicative Congruential Generators with Modulus 2 Super 31-1.

    Science.gov (United States)

    1978-12-01

    Coveyou and MacPherson, 1967) and the lattice tes t (Marsa gl ia,197l). It is well known ( Marsaglia , 1968) that all linear con- gruential generators are...criteria suggested in Knuth (1969) and Marsaglia (1971) for a multipl ier to “pass ” the spectral and lattice tests, respectively, may be considerably...3.18 1.59 I. asource: For RANDU, ( Marsaglia 1971). For Multipliers I through XVI , (Hoaglln 1976). 1.1

  18. Multigene expression in stable CHO cell pools generated with the piggyBac transposon system.

    Science.gov (United States)

    Balasubramanian, Sowmya; Wurm, Florian M; Hacker, David L

    2016-09-01

    Heterogenous populations of recombinant cells (cell pools) stably expressing 1-4 transgenes were generated from Chinese hamster overy (CHO) cells with the piggyBac (PB) transposon system. The cell pools produced different combinations of three model proteins-enhanced green fluorescent protein (EGFP), secreted alkaline phosphatase (SEAP), and a monoclonal IgG1 antibody. Each transgene was present on a separate PB donor plasmid with either the same or a different selection gene. In both cases, we obtained PB-derived cell pools with higher recombinant protein yields than from cell pools generated by conventional gene delivery. In PB-derived cell pools generated using a single selection agent, both protein production and the number of integrated copies of each transgene declined as the number of transfected transgenes increased. However, the total number of integrated transgenes was similar regardless of the number of different transgenes transfected. For PB-derived cell pools generated by selection of each transgene with a different selection agent, the total number of integrated transgenes increased with the number of transfected transgenes. The results suggest that the generation of cell pools producing multiple recombinant proteins is feasible and that the method is more efficient when each individual transgene is selected with a different marker. © 2016 American Institute of Chemical Engineers Biotechnol. Prog., 32:1308-1317, 2016.

  19. Generation of human induced pluripotent stem cells from dermal fibroblasts.

    Science.gov (United States)

    Lowry, W E; Richter, L; Yachechko, R; Pyle, A D; Tchieu, J; Sridharan, R; Clark, A T; Plath, K

    2008-02-26

    The generation of patient-specific pluripotent stem cells has the potential to accelerate the implementation of stem cells for clinical treatment of degenerative diseases. Technologies including somatic cell nuclear transfer and cell fusion might generate such cells but are hindered by issues that might prevent them from being used clinically. Here, we describe methods to use dermal fibroblasts easily obtained from an individual human to generate human induced pluripotent stem (iPS) cells by ectopic expression of the defined transcription factors KLF4, OCT4, SOX2, and C-MYC. The resultant cell lines are morphologically indistinguishable from human embryonic stem cells (HESC) generated from the inner cell mass of a human preimplantation embryo. Consistent with these observations, human iPS cells share a nearly identical gene-expression profile with two established HESC lines. Importantly, DNA fingerprinting indicates that the human iPS cells were derived from the donor material and are not a result of contamination. Karyotypic analyses demonstrate that reprogramming of human cells by defined factors does not induce, or require, chromosomal abnormalities. Finally, we provide evidence that human iPS cells can be induced to differentiate along lineages representative of the three embryonic germ layers indicating the pluripotency of these cells. Our findings are an important step toward manipulating somatic human cells to generate an unlimited supply of patient-specific pluripotent stem cells. In the future, the use of defined factors to change cell fate may be the key to routine nuclear reprogramming of human somatic cells.

  20. From stem cell to erythroblast: regulation of red cell production at multiple levels by multiple hormones.

    Science.gov (United States)

    Lodish, Harvey; Flygare, Johan; Chou, Song

    2010-07-01

    This article reviews the regulation of production of red blood cells at several levels: (1) the ability of erythropoietin and adhesion to a fibronectin matrix to stimulate the rapid production of red cells by inducing terminal proliferation and differentiation of committed erythroid CFU-E progenitors; (2) the regulated expansion of the pool of earlier BFU-E erythroid progenitors by glucocorticoids and other factors that occurs during chronic anemia or inflammation; and (3) the expansion of thehematopoietic cell pool to produce more progenitors of all hematopoietic lineages.

  1. Targeting proliferating cell nuclear antigen and its protein interactions induces apoptosis in multiple myeloma cells.

    Directory of Open Access Journals (Sweden)

    Rebekka Müller

    Full Text Available Multiple myeloma is a hematological cancer that is considered incurable despite advances in treatment strategy during the last decade. Therapies targeting single pathways are unlikely to succeed due to the heterogeneous nature of the malignancy. Proliferating cell nuclear antigen (PCNA is a multifunctional protein essential for DNA replication and repair that is often overexpressed in cancer cells. Many proteins involved in the cellular stress response interact with PCNA through the five amino acid sequence AlkB homologue 2 PCNA-interacting motif (APIM. Thus inhibiting PCNA's protein interactions may be a good strategy to target multiple pathways simultaneously. We initially found that overexpression of peptides containing the APIM sequence increases the sensitivity of cancer cells to contemporary therapeutics. Here we have designed a cell-penetrating APIM-containing peptide, ATX-101, that targets PCNA and show that it has anti-myeloma activity. We found that ATX-101 induced apoptosis in multiple myeloma cell lines and primary cancer cells, while bone marrow stromal cells and primary healthy lymphocytes were much less sensitive. ATX-101-induced apoptosis was caspase-dependent and cell cycle phase-independent. ATX-101 also increased multiple myeloma cells' sensitivity against melphalan, a DNA damaging agent commonly used for treatment of multiple myeloma. In a xenograft mouse model, ATX-101 was well tolerated and increased the anti-tumor activity of melphalan. Therefore, targeting PCNA by ATX-101 may be a novel strategy in multiple myeloma treatment.

  2. Therapeutic strategies targeting B-cells in multiple sclerosis.

    Science.gov (United States)

    Milo, Ron

    2016-07-01

    Multiple sclerosis (MS) is a chronic inflammatory and demyelinating disease of the central nervous system (CNS) that traditionally has been considered to be mediated primarily by T-cells. Increasing evidence, however, suggests the fundamental role of B-cells in the pathogenesis of the disease. Recent strategies targeting B-cells in MS have demonstrated impressive and sometimes surprising results: B-cell depletion by monoclonal antibodies targeting the B-cell surface antigen CD20 (e.g. rituximab, ocrelizumab, ofatumumab) was shown to exert profound anti-inflammatory effect in MS with favorable risk-benefit ratio, with ocrelizumab demonstrating efficacy in both relapsing-remitting (RR) and primary-progressive (PP) MS in phase III clinical trials. Depletion of CD52 expressing T- and B-cells and monocytes by alemtuzumab resulted in impressive and durable suppression of disease activity in RRMS patients. On the other hand, strategies targeting B-cell cytokines such as atacicept resulted in increased disease activity. As our understanding of the biology of B-cells in MS is increasing, new compounds that target B-cells continue to be developed which promise to further expand the armamentarium of MS therapies and allow for more individualized therapy for patients with this complex disease.

  3. Three-dimensional epithelial tissues generated from human embryonic stem cells.

    Science.gov (United States)

    Hewitt, Kyle J; Shamis, Yulia; Carlson, Mark W; Aberdam, Edith; Aberdam, Daniel; Garlick, Jonathan A

    2009-11-01

    The use of pluripotent human embryonic stem (hES) cells for tissue engineering may provide advantages over traditional sources of progenitor cells because of their ability to give rise to multiple cell types and their unlimited expansion potential. We derived cell populations with properties of ectodermal and mesenchymal cells in two-dimensional culture and incorporated these divergent cell populations into three-dimensional (3D) epithelial tissues. When grown in specific media and substrate conditions, two-dimensional cultures were enriched in cells (EDK1) with mesenchymal morphology and surface markers. Cells with a distinct epithelial morphology (HDE1) that expressed cytokeratin 12 and beta-catenin at cell junctions became the predominant cell type when EDK1 were grown on surfaces enriched in keratinocyte-derived extracellular matrix proteins. When these cells were incorporated into the stromal and epithelial tissue compartments of 3D tissues, they generated multilayer epithelia similar to those generated with foreskin-derived epithelium and fibroblasts. Three-dimensional tissues demonstrated stromal cells with morphologic features of mature fibroblasts, type IV collagen deposition in the basement membrane, and a stratified epithelium that expressed cytokeratin 12. By deriving two distinct cell lineages from a common hES cell source to fabricate complex tissues, it is possible to explore environmental cues that will direct hES-derived cells toward optimal tissue form and function.

  4. Exposure to hypomagnetic field space for multiple generations causes amnesia in Drosophila melanogaster.

    Science.gov (United States)

    Zhang, Bin; Lu, Huimin; Xi, Wang; Zhou, Xianju; Xu, Shiyu; Zhang, Ke; Jiang, Jinchang; Li, Yan; Guo, Aike

    2004-11-23

    This is the introduction of Drosophila into the study of learning and memory affected by removal of the geomagnetic field (GMF) for successive generations. Using the operant visual learning/memory paradigm at a flight simulator, the present study revealed that wild-type flies raised in a hypomagnetic field environment continuously for 10 successive generations were gradually impaired in visual conditioning learning and memory formation and finally the 10th generation flies became morphs of nonlearners and completely amnesiac. The control experiments show that the impairment could not be ascribed to any apparent sensorimotor problems in Drosophila. The reverse shift from hypomagnetic field (HMF) to natural GMF restored the GMF-free induced amnesia fully after six consecutive generations. Thus, our findings demonstrate conclusively that some serious, but reversible learning and memory impairment may occur for living organisms in a prolonged separation from GMF over many consecutive generations. And Drosophila has the potential to develop into a new model organism for the study of the neurobiology of magnetism for multiple generations.

  5. Generating native user interfaces for multiple devices by means of model transformation

    Institute of Scientific and Technical Information of China (English)

    Ignacio MARIN; Francisco ORTIN; German PEDROSA; Javier RODRIGUEZ

    2015-01-01

    In the last years, the types of devices used to access information systems have notably increased using different operating systems, screen sizes, interaction mechanisms, and software features. This device fragmentation is an important issue to tackle when developing native mobile service front-end applications. To address this issue, we propose the generation of native user interfaces (UIs) by means of model transformations, following the model-based user interface (MBUI) paradigm. The resulting MBUI framework, called LIZARD, generates applications for multiple target platforms. LIZARD allows the defi nition of applications at a high level of abstraction, and applies model transformations to generate the target native UI considering the specifi c features of target platforms. The generated applications follow the UI design guidelines and the architectural and design patterns specifi ed by the corresponding operating system manufacturer. The objective is not to generate generic applications following the lowest-common-denominator approach, but to follow the particular guidelines specifi ed for each target device. We present an example application modeled in LIZARD, generating different UIs for Windows Phone and two types of Android devices (smartphones and tablets).

  6. Generation maintenance scheduling based on multiple ob jectives and their relationship analysis

    Institute of Scientific and Technical Information of China (English)

    Jun-peng ZHAN; Chuang-xin GUO; Qing-hua WU; Lu-liang ZHANG; Hong-jun FU

    2014-01-01

    In a market environment of power systems, each producer pursues its maximal profit while the independent system operator is in charge of the system reliability and the minimization of the total generation cost when generating the generation maintenance scheduling (GMS). Thus, the GMS is inherently a multi-objective optimization problem as its objectives usually conflict with each other. This paper proposes a multi-objective GMS model in a market environment which includes three types of objectives, i.e., each producer’s profit, the system reliability, and the total generation cost. The GMS model has been solved by the group search optimizer with multiple producers (GSOMP) on two test systems. The simulation results show that the model is well solved by the GSOMP with a set of evenly distributed Pareto-optimal solutions obtained. The simulation results also illustrate that one producer’s profit conflicts with another one’s, that the total generation cost does not conflict with the profit of the producer possessing the cheapest units while the total generation cost conflicts with the other producers’ profits, and that the reliability objective conflicts with the other objectives.

  7. Automated Mosaicking of Multiple 3d Point Clouds Generated from a Depth Camera

    Science.gov (United States)

    Kim, H.; Yoon, W.; Kim, T.

    2016-06-01

    In this paper, we propose a method for automated mosaicking of multiple 3D point clouds generated from a depth camera. A depth camera generates depth data by using ToF (Time of Flight) method and intensity data by using intensity of returned signal. The depth camera used in this paper was a SR4000 from MESA Imaging. This camera generates a depth map and intensity map of 176 x 44 pixels. Generated depth map saves physical depth data with mm of precision. Generated intensity map contains texture data with many noises. We used texture maps for extracting tiepoints and depth maps for assigning z coordinates to tiepoints and point cloud mosaicking. There are four steps in the proposed mosaicking method. In the first step, we acquired multiple 3D point clouds by rotating depth camera and capturing data per rotation. In the second step, we estimated 3D-3D transformation relationships between subsequent point clouds. For this, 2D tiepoints were extracted automatically from the corresponding two intensity maps. They were converted into 3D tiepoints using depth maps. We used a 3D similarity transformation model for estimating the 3D-3D transformation relationships. In the third step, we converted local 3D-3D transformations into a global transformation for all point clouds with respect to a reference one. In the last step, the extent of single depth map mosaic was calculated and depth values per mosaic pixel were determined by a ray tracing method. For experiments, 8 depth maps and intensity maps were used. After the four steps, an output mosaicked depth map of 454x144 was generated. It is expected that the proposed method would be useful for developing an effective 3D indoor mapping method in future.

  8. Effect of failures and repairs on multiple cell production lines

    Energy Technology Data Exchange (ETDEWEB)

    Legato, P.; Bobbio, A.; Roberti, L.

    1989-01-01

    This paper examines a production line composed of multiple stages, or cells, which are passed in sequential order to arrive to the final product. Two possible coordination disciplines are considered, namely: the classical tandem arrangement of sequential working centers with input buffer and the kanban scheme, considered the Japanese shop floor realization of the Just-In-Time (JIT) manifacturing approach. The production line is modelled and analysed by means of Stochastic Petri Nets (SPN). Finally an analysis is made of the possibility that the working cells can incur failure/repair cycles perturbing the production flow of the line and thus reduce performance indices.

  9. B cell-directed therapies in multiple sclerosis.

    Science.gov (United States)

    Gasperi, Christiane; Stüve, Olaf; Hemmer, Bernhard

    2016-01-01

    Multiple sclerosis (MS) is a chronic inflammatory neurological disease of the CNS that goes along with demyelination and neurodegeneration. It is probably caused by an autoimmune response against the CNS, which emerges from the interplay of genetic and environmental factors. Although major progress has been made in the treatment of MS, it is still the leading cause for acquired nontraumatic neurological disability in young adults. Several therapeutic agents have been approved for the treatment of relapsing-remitting MS (RRMS), aiming at the reduction of relapses and a delay in disability progression. Three therapeutic monoclonal antibodies targeting CD20-positive B cells (rituximab, ocrelizumab and ofatumumab) were investigated in MRI-based Phase II and Phase III trials in RRMS, providing consistent evidence for a disease-ameliorating effect of B cell depleting therapies in MS. Here, we discuss the role of B cells and review current and future therapeutic approaches to target B cells in MS.

  10. Equine dendritic cells generated with horse serum have enhanced functionality in comparison to dendritic cells generated with fetal bovine serum

    OpenAIRE

    Ziegler, A; Everett, H.; Hamza, E; Garbani, M; Gerber, V.; Marti, E; Steinbach, F

    2016-01-01

    Background: Dendritic cells are professional antigen-presenting cells that play an essential role in the initiation and modulation of T cell responses. They have been studied widely for their potential clinical applications, but for clinical use to be successful, alternatives to xenogeneic substances like fetal bovine serum (FBS) in cell culture need to be found. Protocols for the generation of dendritic cells ex vivo from monocytes are well established for several species, including horses. ...

  11. HIF-1α inhibition blocks the cross talk between multiple myeloma plasma cells and tumor microenvironment

    Energy Technology Data Exchange (ETDEWEB)

    Borsi, Enrica, E-mail: enrica.borsi2@unibo.it [Department of Experimental Diagnostic and Specialty Medicine (DIMES), “L. and A. Seràgnoli”, Bologna University School of Medicine, S. Orsola' s University Hospital (Italy); Perrone, Giulia [Fondazione IRCCS Istituto Nazionale dei Tumori, Hematology Department, Via Venezian 1, 20133 Milano (Italy); Terragna, Carolina; Martello, Marina; Zamagni, Elena; Tacchetti, Paola; Pantani, Lucia; Brioli, Annamaria; Dico, Angela Flores; Zannetti, Beatrice Anna; Rocchi, Serena; Cavo, Michele [Department of Experimental Diagnostic and Specialty Medicine (DIMES), “L. and A. Seràgnoli”, Bologna University School of Medicine, S. Orsola' s University Hospital (Italy)

    2014-11-01

    Multiple myeloma (MM) is a malignant disorder of post-germinal center B cells, characterized by the clonal proliferation of malignant plasma cells (PCs) within the bone marrow (BM). The reciprocal and complex interactions that take place between the different compartments of BM and the MM cells result in tumor growth, angiogenesis, bone disease, and drug resistance. Given the importance of the BM microenvironment in MM pathogenesis, we investigated the possible involvement of Hypoxia-Inducible transcription Factor-1 alpha (HIF-1α) in the PCs-bone marrow stromal cells interplay. To test this hypothesis, we used EZN-2968, a 3rd generation antisense oligonucleotide against HIF-1α, to inhibit HIF-1α functions. Herein, we provide evidence that the interaction between MM cells and BM stromal cells is drastically reduced upon HIF-1α down-modulation. Notably, we showed that upon exposure to HIF-1α inhibitor, neither the incubation with IL-6 nor the co-culture with BM stromal cells were able to revert the anti-proliferative effect induced by EZN-2968. Moreover, we observed a down-modulation of cytokine-induced signaling cascades and a reduction of MM cells adhesion capability to the extracellular matrix proteins in EZN-2968-treated samples. Taken together, these results strongly support the concept that HIF-1α plays a critical role in the interactions between bone BM cells and PCs in Multiple Myeloma. - Highlights: • HIF-1α inhibition induces a mild apoptotic cell death. • Down-modulation of cytokine-induced signaling cascades upon HIF-1α inhibition. • Reduced interaction between MM cells and BMSCs upon HIF-1α down-modulation. • Reduced PCs adhesion to the extracellular matrix protein induced by EZN-2968. • HIF-1α inhibition may be an attractive therapeutic strategy for Multiple Myeloma.

  12. T cells in multiple sclerosis and experimental autoimmune encephalomyelitis.

    LENUS (Irish Health Repository)

    Fletcher, J M

    2012-02-01

    Multiple sclerosis (MS) is a demyelinating inflammatory disorder of the central nervous system (CNS), which involves autoimmune responses to myelin antigens. Studies in experimental autoimmune encephalomyelitis (EAE), an animal model for MS, have provided convincing evidence that T cells specific for self-antigens mediate pathology in these diseases. Until recently, T helper type 1 (Th1) cells were thought to be the main effector T cells responsible for the autoimmune inflammation. However more recent studies have highlighted an important pathogenic role for CD4(+) T cells that secrete interleukin (IL)-17, termed Th17, but also IL-17-secreting gammadelta T cells in EAE as well as other autoimmune and chronic inflammatory conditions. This has prompted intensive study of the induction, function and regulation of IL-17-producing T cells in MS and EAE. In this paper, we review the contribution of Th1, Th17, gammadelta, CD8(+) and regulatory T cells as well as the possible development of new therapeutic approaches for MS based on manipulating these T cell subtypes.

  13. Stabilization Of Apoptotic Cells: Generation Of Zombie Cells

    Directory of Open Access Journals (Sweden)

    José A. Sánchez Alcázar

    2015-08-01

    Stabilization of apoptotic cells can be used for reliable detection and quantification of apoptosis in cultured cells and may allow a safer administration of apoptotic cells in clinical applications. Furthermore, it opens new avenues in the functional reconstruction of apoptotic cells for longer preservation.

  14. Generating trunk neural crest from human pluripotent stem cells

    OpenAIRE

    Miller Huang; Matthew L. Miller; McHenry, Lauren K.; Tina Zheng; Qiqi Zhen; Shirin Ilkhanizadeh; Conklin, Bruce R.; Bronner, Marianne E.; Weiss, William A.

    2016-01-01

    Neural crest cells (NCC) are stem cells that generate different lineages, including neuroendocrine, melanocytic, cartilage, and bone. The differentiation potential of NCC varies according to the level from which cells emerge along the neural tube. For example, only anterior “cranial” NCC form craniofacial bone, whereas solely posterior “trunk” NCC contribute to sympathoadrenal cells. Importantly, the isolation of human fetal NCC carries ethical and scientific challenges, as NCC induction typi...

  15. Factors influencing municipal solid waste generation in China: a multiple statistical analysis study.

    Science.gov (United States)

    Liu, Chen; Wu, Xin-wu

    2011-04-01

    A relationship between the waste production and socio-economic factors is essential in waste management. In the present study, the factors influencing municipal solid waste generation in China were investigated by multiple statistical analysis. Twelve items were chosen for investigation: GDP, per capita GDP, urban population, the proportion of urban population, the area of urban construction, the area of paved roads, the area of urban gardens and green areas, the number of the large cities, annual per capita disposable income of urban households, annual per capita consumption expenditure of urban households, total energy consumption and annual per capital consumption for households. Two methodologies from multiple statistical analysis were selected; specifically principal components analysis (PCA) and cluster analysis (CA). Three new dimensions were identified by PCA: component 1: economy and urban development; component 2: energy consumption; and component 3: urban scale. The three components together accounted for 99.1% of the initial variance. The results show that economy and urban development are important items influencing MSW generation. The proportion of urban population and urban population had the highest loadings in all factors. The relationship between growth of gross domestic product (GDP) and production of MSW was not as clear-cut as often assumed in China, a situation that is more likely to apply to developed countries. Energy consumption was another factor considered in our study of MSW generation. In addition, the annual MSW quantity variation was investigated by cluster analysis.

  16. Multiple Chaotic Central Pattern Generators with Learning for Legged Locomotion and Malfunction Compensation

    DEFF Research Database (Denmark)

    Ren, Guanjiao; Chen, Weihai; Dasgupta, Sakyasingha

    2015-01-01

    on a simulated annealing algorithm. In a normal situation, the CPGs synchronize and their dynamics are identical. With leg malfunction or disability, the CPGs lose synchronization leading to independent dynamics. In this case, the learning mechanism is applied to automatically adjust the remaining legs...... chaotic CPG controller has difficulties dealing with leg malfunction. Specifically, in the scenarios presented here, its movement permanently deviates from the desired trajectory. To address this problem, we extend the single chaotic CPG to multiple CPGs with learning. The learning mechanism is based...... in a physical simulation of a quadruped as well as a hexapod robot and finally in a real six-legged walking machine called AMOSII. The experimental results presented here reveal that using multiple CPGs with learning is an effective approach for adaptive locomotion generation where, for instance, different body...

  17. Generating and executing programs for a floating point single instruction multiple data instruction set architecture

    Science.gov (United States)

    Gschwind, Michael K

    2013-04-16

    Mechanisms for generating and executing programs for a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA) are provided. A computer program product comprising a computer recordable medium having a computer readable program recorded thereon is provided. The computer readable program, when executed on a computing device, causes the computing device to receive one or more instructions and execute the one or more instructions using logic in an execution unit of the computing device. The logic implements a floating point (FP) only single instruction multiple data (SIMD) instruction set architecture (ISA), based on data stored in a vector register file of the computing device. The vector register file is configured to store both scalar and floating point values as vectors having a plurality of vector elements.

  18. Organized Emergence of Multiple-Generations of Teeth in Snakes Is Dysregulated by Activation of Wnt/Beta-Catenin Signalling

    Science.gov (United States)

    Gaete, Marcia; Tucker, Abigail S.

    2013-01-01

    In contrast to mammals, most reptiles constantly regenerate their teeth. In the snake, the epithelial dental lamina ends in a successional lamina, which proliferates and elongates forming multiple tooth generations, all linked by a permanent dental lamina. To investigate the mechanisms used to control the initiation of new tooth germs in an ordered sequential pattern we utilized the polyphodont (multiple-generation) corn snake (Pantherophis guttatus). We observed that the dental lamina expressed the transcription factor Sox2, a multipotent stem cell marker, whereas the successional lamina cells expressed the transcription factor Lef1, a Wnt/β-catenin pathway target gene. Activation of the Wnt/β-catenin pathway in culture increased the number of developing tooth germs, in comparison to control untreated cultures. These additional tooth germs budded off from ectopic positions along the dental lamina, rather than in an ordered sequence from the successional lamina. Wnt/β-catenin activation enhanced cell proliferation, particularly in normally non-odontogenic regions of the dental lamina, which widely expressed Lef1, restricting the Sox2 domain. This suggests an expansion of the successional lamina at the expense of the dental lamina. Activation of the Wnt/β-catenin pathway in cultured snake dental organs, therefore, led to changes in proliferation and to the molecular pattern of the dental lamina, resulting in loss of the organised emergence of tooth germs. These results suggest that epithelial compartments are critical for the arrangement of organs that develop in sequence, and highlight the role of Wnt/β-catenin signalling in such processes. PMID:24019968

  19. Organized emergence of multiple-generations of teeth in snakes is dysregulated by activation of Wnt/beta-catenin signalling.

    Science.gov (United States)

    Gaete, Marcia; Tucker, Abigail S

    2013-01-01

    In contrast to mammals, most reptiles constantly regenerate their teeth. In the snake, the epithelial dental lamina ends in a successional lamina, which proliferates and elongates forming multiple tooth generations, all linked by a permanent dental lamina. To investigate the mechanisms used to control the initiation of new tooth germs in an ordered sequential pattern we utilized the polyphodont (multiple-generation) corn snake (Pantherophis guttatus). We observed that the dental lamina expressed the transcription factor Sox2, a multipotent stem cell marker, whereas the successional lamina cells expressed the transcription factor Lef1, a Wnt/β-catenin pathway target gene. Activation of the Wnt/β-catenin pathway in culture increased the number of developing tooth germs, in comparison to control untreated cultures. These additional tooth germs budded off from ectopic positions along the dental lamina, rather than in an ordered sequence from the successional lamina. Wnt/β-catenin activation enhanced cell proliferation, particularly in normally non-odontogenic regions of the dental lamina, which widely expressed Lef1, restricting the Sox2 domain. This suggests an expansion of the successional lamina at the expense of the dental lamina. Activation of the Wnt/β-catenin pathway in cultured snake dental organs, therefore, led to changes in proliferation and to the molecular pattern of the dental lamina, resulting in loss of the organised emergence of tooth germs. These results suggest that epithelial compartments are critical for the arrangement of organs that develop in sequence, and highlight the role of Wnt/β-catenin signalling in such processes.

  20. Organized emergence of multiple-generations of teeth in snakes is dysregulated by activation of Wnt/beta-catenin signalling.

    Directory of Open Access Journals (Sweden)

    Marcia Gaete

    Full Text Available In contrast to mammals, most reptiles constantly regenerate their teeth. In the snake, the epithelial dental lamina ends in a successional lamina, which proliferates and elongates forming multiple tooth generations, all linked by a permanent dental lamina. To investigate the mechanisms used to control the initiation of new tooth germs in an ordered sequential pattern we utilized the polyphodont (multiple-generation corn snake (Pantherophis guttatus. We observed that the dental lamina expressed the transcription factor Sox2, a multipotent stem cell marker, whereas the successional lamina cells expressed the transcription factor Lef1, a Wnt/β-catenin pathway target gene. Activation of the Wnt/β-catenin pathway in culture increased the number of developing tooth germs, in comparison to control untreated cultures. These additional tooth germs budded off from ectopic positions along the dental lamina, rather than in an ordered sequence from the successional lamina. Wnt/β-catenin activation enhanced cell proliferation, particularly in normally non-odontogenic regions of the dental lamina, which widely expressed Lef1, restricting the Sox2 domain. This suggests an expansion of the successional lamina at the expense of the dental lamina. Activation of the Wnt/β-catenin pathway in cultured snake dental organs, therefore, led to changes in proliferation and to the molecular pattern of the dental lamina, resulting in loss of the organised emergence of tooth germs. These results suggest that epithelial compartments are critical for the arrangement of organs that develop in sequence, and highlight the role of Wnt/β-catenin signalling in such processes.

  1. Enhanced biofilm distribution and cell performance of microfluidic microbial fuel cells with multiple anolyte inlets.

    Science.gov (United States)

    Yang, Yang; Ye, Dingding; Liao, Qiang; Zhang, Pengqing; Zhu, Xun; Li, Jun; Fu, Qian

    2016-05-15

    A laminar-flow controlled microfluidic microbial fuel cell (MMFC) is considered as a promising approach to be a bio-electrochemical system (BES). But poor bacterial colonization and low power generation are two severe bottlenecks to restrict its development. In this study, we reported a MMFC with multiple anolyte inlets (MMFC-MI) to enhance the biofilm formation and promote the power density of MMFCs. Voltage profiles during the inoculation process demonstrated MMFC-MI had a faster start-up process than the conventional microfluidic microbial fuel cell with one inlet (MMFC-OI). Meanwhile, benefited from the periodical replenishment of boundary layer near the electrode, a more densely-packed bacterial aggregation was observed along the flow direction and also the substantially low internal resistance for MMFC-MI. Most importantly, the output power density of MMFC-MI was the highest value among the reported µl-scale MFCs to our best knowledge. The presented MMFC-MI appears promising for bio-chip technology and extends the scope of microfluidic energy.

  2. Stationary Size Distributions of Growing Cells with Binary and Multiple Cell Division

    Science.gov (United States)

    Rading, M. M.; Engel, T. A.; Lipowsky, R.; Valleriani, A.

    2011-10-01

    Populations of unicellular organisms that grow under constant environmental conditions are considered theoretically. The size distribution of these cells is calculated analytically, both for the usual process of binary division, in which one mother cell produces always two daughter cells, and for the more complex process of multiple division, in which one mother cell can produce 2 n daughter cells with n=1,2,3,… . The latter mode of division is inspired by the unicellular algae Chlamydomonas reinhardtii. The uniform response of the whole population to different environmental conditions is encoded in the individual rates of growth and division of the cells. The analytical treatment of the problem is based on size-dependent rules for cell growth and stochastic transition processes for cell division. The comparison between binary and multiple division shows that these different division processes lead to qualitatively different results for the size distribution and the population growth rates.

  3. Generating and Analyzing N-dimensional Hilbert Cell

    Institute of Scientific and Technical Information of China (English)

    FENG Yucai; LI Chenyang

    2005-01-01

    In this paper, two algorithms are presented for generating two code scan lists of an N-dimensional Hilbert cell, and a formal proof of the backward encoding algorithm is given. On the basis of the self-simi-larity properties of a Hilbert curve, this paper gives a novel algorithm for generating a static evolvement rule table through analyzing a Hilbert cell. By looking up the static evolvement rule table, the N-dimensional Hilbert mappings are efficiently implemented.

  4. Generation of diverse neural cell types through direct conversion

    Institute of Scientific and Technical Information of China (English)

    Gayle; F; Petersen; Padraig; M; Strappe

    2016-01-01

    A characteristic of neurological disorders is the loss of critical populations of cells that the body is unable to replace,thus there has been much interest in identifying methods of generating clinically relevant numbers of cells to replace those that have been damaged or lost.The process of neural direct conversion,in which cells of one lineage are converted into cells of a neural lineage without first inducing pluripotency,shows great potential,with evidence of the generation of a range of functional neural cell types both in vitro and in vivo,through viral and non-viral delivery of exogenous factors,as well as chemical induction methods.Induced neural cells have been proposed as an attractive alternative to neural cells derived from embryonic or induced pluripotent stem cells,with prospective roles in the investigation of neurological disorders,including neurodegenerative disease modelling,drug screening,and cellular replacement for regenerative medicine applications,however further investigations into improving the efficacy and safety of these methods need to be performed before neural direct conversion becomes a clinically viable option.In this review,we describe the generation of diverse neural cell types via direct conversion of somatic cells,with comparison against stem cell-based approaches,as well as discussion of their potential research and clinical applications.

  5. Generation of cardiac pacemaker cells by programming and differentiation.

    Science.gov (United States)

    Husse, Britta; Franz, Wolfgang-Michael

    2016-07-01

    A number of diseases are caused by faulty function of the cardiac pacemaker and described as "sick sinus syndrome". The medical treatment of sick sinus syndrome with electrical pacemaker implants in the diseased heart includes risks. These problems may be overcome via "biological pacemaker" derived from different adult cardiac cells or pluripotent stem cells. The generation of cardiac pacemaker cells requires the understanding of the pacing automaticity. Two characteristic phenomena the "membrane-clock" and the "Ca(2+)-clock" are responsible for the modulation of the pacemaker activity. Processes in the "membrane-clock" generating the spontaneous pacemaker firing are based on the voltage-sensitive membrane ion channel activity starting with slow diastolic depolarization and discharging in the action potential. The influence of the intracellular Ca(2+) modulating the pacemaker activity is characterized by the "Ca(2+)-clock". The generation of pacemaker cells started with the reprogramming of adult cardiac cells by targeted induction of one pacemaker function like HCN1-4 overexpression and enclosed in an activation of single pacemaker specific transcription factors. Reprogramming of adult cardiac cells with the transcription factor Tbx18 created cardiac cells with characteristic features of cardiac pacemaker cells. Another key transcription factor is Tbx3 specifically expressed in the cardiac conduction system including the sinoatrial node and sufficient for the induction of the cardiac pacemaker gene program. For a successful cell therapeutic practice, the generated cells should have all regulating mechanisms of cardiac pacemaker cells. Otherwise, the generated pacemaker cells serve only as investigating model for the fundamental research or as drug testing model for new antiarrhythmics. This article is part of a Special Issue entitled: Cardiomyocyte Biology: Integration of Developmental and Environmental Cues in the Heart edited by Marcus Schaub and Hughes Abriel.

  6. Noise measurements for single and multiple operation of 50 kw wind turbine generators

    Science.gov (United States)

    Hubbard, H. H.; Shepherd, K. P.

    1982-01-01

    The noise characteristics of the U.S. Windpower Inc., 50 kw wind turbine generator were measured at various distances from 30 m to 1100 m and for a range of output power. The generated noise is affected by the aerodynamic wakes of the tower legs at frequencies below about 120 Hz and the blade trailing edge thickness at frequencies of about 2 kHz. Rope strakes and airfoil fairings on the legs did not result in substantial noise reductions. Sharpening the blade trailing edges near the tip was effective in reducing broad band noise near 2 kHz. For multiple machines the sound fields are superposed. A three-fold increase in number of machines (from 1 to 3) results in a predicted increase in he sound pressure level of about 5 dB. The detection threshold for 14 machines operating in a 13 - 20 mph wind is observed to be at approximately 1160 m in the downwind direction.

  7. Optimal placement and sizing of multiple distributed generating units in distribution

    Directory of Open Access Journals (Sweden)

    D. Rama Prabha

    2016-06-01

    Full Text Available Distributed generation (DG is becoming more important due to the increase in the demands for electrical energy. DG plays a vital role in reducing real power losses, operating cost and enhancing the voltage stability which is the objective function in this problem. This paper proposes a multi-objective technique for optimally determining the location and sizing of multiple distributed generation (DG units in the distribution network with different load models. The loss sensitivity factor (LSF determines the optimal placement of DGs. Invasive weed optimization (IWO is a population based meta-heuristic algorithm based on the behavior of weeds. This algorithm is used to find optimal sizing of the DGs. The proposed method has been tested for different load models on IEEE-33 bus and 69 bus radial distribution systems. This method has been compared with other nature inspired optimization methods. The simulated results illustrate the good applicability and performance of the proposed method.

  8. Quantitative phosphoproteomics of proteasome inhibition in multiple myeloma cells.

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    Feng Ge

    Full Text Available BACKGROUND: The proteasome inhibitor bortezomib represents an important advance in the treatment of multiple myeloma (MM. Bortezomib inhibits the activity of the 26S proteasome and induces cell death in a variety of tumor cells; however, the mechanism of cytotoxicity is not well understood. METHODOLOGY/PRINCIPAL FINDINGS: We investigated the differential phosphoproteome upon proteasome inhibition by using stable isotope labeling by amino acids in cell culture (SILAC in combination with phosphoprotein enrichment and LC-MS/MS analysis. In total 233 phosphoproteins were identified and 72 phosphoproteins showed a 1.5-fold or greater change upon bortezomib treatment. The phosphoproteins with expression alterations encompass all major protein classes, including a large number of nucleic acid binding proteins. Site-specific phosphopeptide quantitation revealed that Ser38 phosphorylation on stathmin increased upon bortezomib treatment, suggesting new mechanisms associated to bortezomib-induced apoptosis in MM cells. Further studies demonstrated that stathmin phosphorylation profile was modified in response to bortezomib treatment and the regulation of stathmin by phosphorylation at specific Ser/Thr residues participated in the cellular response induced by bortezomib. CONCLUSIONS/SIGNIFICANCE: Our systematic profiling of phosphorylation changes in response to bortezomib treatment not only advanced the global mechanistic understanding of the action of bortezomib on myeloma cells but also identified previously uncharacterized signaling proteins in myeloma cells.

  9. Multiple Modes of Cell Death Discovered in a Prokaryotic (Cyanobacterial Endosymbiont.

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    Weiwen Zheng

    Full Text Available Programmed cell death (PCD is a genetically-based cell death mechanism with vital roles in eukaryotes. Although there is limited consensus on similar death mode programs in prokaryotes, emerging evidence suggest that PCD events are operative. Here we present cell death events in a cyanobacterium living endophytically in the fern Azolla microphylla, suggestive of PCD. This symbiosis is characterized by some unique traits such as a synchronized development, a vertical transfer of the cyanobacterium between plant generations, and a highly eroding cyanobacterial genome. A combination of methods was used to identify cell death modes in the cyanobacterium. Light- and electron microscopy analyses showed that the proportion of cells undergoing cell death peaked at 53.6% (average 20% of the total cell population, depending on the cell type and host developmental stage. Biochemical markers used for early and late programmed cell death events related to apoptosis (Annexin V-EGFP and TUNEL staining assays, together with visualization of cytoskeleton alterations (FITC-phalloidin staining, showed that all cyanobacterial cell categories were affected by cell death. Transmission electron microscopy revealed four modes of cell death: apoptotic-like, autophagic-like, necrotic-like and autolytic-like. Abiotic stresses further enhanced cell death in a dose and time dependent manner. The data also suggest that dynamic changes in the peptidoglycan cell wall layer and in the cytoskeleton distribution patterns may act as markers for the various cell death modes. The presence of a metacaspase homolog (domain p20 further suggests that the death modes are genetically programmed. It is therefore concluded that multiple, likely genetically programmed, cell death modes exist in cyanobacteria, a finding that may be connected with the evolution of cell death in the plant kingdom.

  10. Ablation of coactivator Med1 switches the cell fate of dental epithelia to that generating hair.

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    Keigo Yoshizaki

    Full Text Available Cell fates are determined by specific transcriptional programs. Here we provide evidence that the transcriptional coactivator, Mediator 1 (Med1, is essential for the cell fate determination of ectodermal epithelia. Conditional deletion of Med1 in vivo converted dental epithelia into epidermal epithelia, causing defects in enamel organ development while promoting hair formation in the incisors. We identified multiple processes by which hairs are generated in Med1 deficient incisors: 1 dental epithelial stem cells lacking Med 1 fail to commit to the dental lineage, 2 Sox2-expressing stem cells extend into the differentiation zone and remain multi-potent due to reduced Notch1 signaling, and 3 epidermal fate is induced by calcium as demonstrated in dental epithelial cell cultures. These results demonstrate that Med1 is a master regulator in adult stem cells to govern epithelial cell fate.

  11. A Multiple-Model Approach for Synchronous Generator Nonlinear System Identification

    Science.gov (United States)

    Ahmadi, Seyed Salman; Karrari, Mehdi

    2012-07-01

    In this paper, a multiple model approach is proposed for the identification of synchronous generators. In the literature, the same structure often is used for all local models. Therefore, to obtain a precise model for the operating condition of the synchronous generator with severely nonlinear behavior, many local models are required. The proposed method determines the complexity of local models based on complexity of behavior of the synchronous generator at different operating conditions. There are two choices for increasing model precision at each iteration of the proposed method: (i) increasing the number of local models in one region, or (ii) increasing local model complexity in the same region. The proposed method has been tested on experimental data collected on a 3 kVA micro-machine. In the study, the field voltage is considered as the input and the active output power and the terminal voltage are considered as the outputs of the synchronous generator. The proposed method provides a more precise model with fewer parameters compared to some well known methods such as LOLIMOT and global polynomial models.

  12. Generation of broadband spontaneous parametric fluorescence using multiple bulk nonlinear crystals

    CERN Document Server

    Okano, Masayuki; Tanaka, Akira; Subashchandran, Shanthi; Takeuchi, Shigeki; 10.1364/OE.20.013977

    2012-01-01

    We propose a novel method for generating broadband spontaneous parametric fluorescence by using a set of bulk nonlinear crystals (NLCs). We also demonstrate this scheme experimentally. Our method employs a superposition of spontaneous parametric fluorescence spectra generated using multiple bulk NLCs. A typical bandwidth of 160 nm (73 THz) with a degenerate wavelength of 808 nm was achieved using two beta-barium-borate (BBO) crystals, whereas a typical bandwidth of 75 nm (34 THz) was realized using a single BBO crystal. We also observed coincidence counts of generated photon pairs in a non-collinear configuration. The bandwidth could be further broadened by increasing the number of NLCs. Our demonstration suggests that a set of four BBO crystals could realize a bandwidth of approximately 215 nm (100 THz).We also discuss the stability of Hong-Ou-Mandel two-photon interference between the parametric fluorescence generated by this scheme. Our simple scheme is easy to implement with conventional NLCs and does not...

  13. Generation of broadband spontaneous parametric fluorescence using multiple bulk nonlinear crystals.

    Science.gov (United States)

    Okano, Masayuki; Okamoto, Ryo; Tanaka, Akira; Subashchandran, Shanthi; Takeuchi, Shigeki

    2012-06-18

    We propose a novel method for generating broadband spontaneous parametric fluorescence by using a set of bulk nonlinear crystals (NLCs). We also demonstrate this scheme experimentally. Our method employs a superposition of spontaneous parametric fluorescence spectra generated using multiple bulk NLCs. A typical bandwidth of 160 nm (73 THz) with a degenerate wavelength of 808 nm was achieved using two β-barium-borate (BBO) crystals, whereas a typical bandwidth of 75 nm (34 THz) was realized using a single BBO crystal. We also observed coincidence counts of generated photon pairs in a non-collinear configuration. The bandwidth could be further broadened by increasing the number of NLCs. Our demonstration suggests that a set of four BBO crystals could realize a bandwidth of approximately 215 nm (100 THz). We also discuss the stability of Hong-Ou-Mandel two-photon interference between the parametric fluorescence generated by this scheme. Our simple scheme is easy to implement with conventional NLCs and does not require special devices.

  14. GenNon-h: Generating multiple sequence alignments on nonhomogeneous phylogenetic trees

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    Kedzierska Anna M

    2012-08-01

    Full Text Available Abstract Background A number of software packages are available to generate DNA multiple sequence alignments (MSAs evolved under continuous-time Markov processes on phylogenetic trees. On the other hand, methods of simulating the DNA MSA directly from the transition matrices do not exist. Moreover, existing software restricts to the time-reversible models and it is not optimized to generate nonhomogeneous data (i.e. placing distinct substitution rates at different lineages. Results We present the first package designed to generate MSAs evolving under discrete-time Markov processes on phylogenetic trees, directly from probability substitution matrices. Based on the input model and a phylogenetic tree in the Newick format (with branch lengths measured as the expected number of substitutions per site, the algorithm produces DNA alignments of desired length. GenNon-h is publicly available for download. Conclusion The software presented here is an efficient tool to generate DNA MSAs on a given phylogenetic tree. GenNon-h provides the user with the nonstationary or nonhomogeneous phylogenetic data that is well suited for testing complex biological hypotheses, exploring the limits of the reconstruction algorithms and their robustness to such models.

  15. Timing the generation of distinct retinal cells by homeobox proteins.

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    Sarah Decembrini

    2006-09-01

    Full Text Available The reason why different types of vertebrate nerve cells are generated in a particular sequence is still poorly understood. In the vertebrate retina, homeobox genes play a crucial role in establishing different cell identities. Here we provide evidence of a cellular clock that sequentially activates distinct homeobox genes in embryonic retinal cells, linking the identity of a retinal cell to its time of generation. By in situ expression analysis, we found that the three Xenopus homeobox genes Xotx5b, Xvsx1, and Xotx2 are initially transcribed but not translated in early retinal progenitors. Their translation requires cell cycle progression and is sequentially activated in photoreceptors (Xotx5b and bipolar cells (Xvsx1 and Xotx2. Furthermore, by in vivo lipofection of "sensors" in which green fluorescent protein translation is under control of the 3' untranslated region (UTR, we found that the 3' UTRs of Xotx5b, Xvsx1, and Xotx2 are sufficient to drive a spatiotemporal pattern of translation matching that of the corresponding proteins and consistent with the time of generation of photoreceptors (Xotx5b and bipolar cells (Xvsx1 and Xotx2. The block of cell cycle progression of single early retinal progenitors impairs their differentiation as photoreceptors and bipolar cells, but is rescued by the lipofection of Xotx5b and Xvsx1 coding sequences, respectively. This is the first evidence to our knowledge that vertebrate homeobox proteins can work as effectors of a cellular clock to establish distinct cell identities.

  16. Generation of human melanocytes from induced pluripotent stem cells.

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    Shigeki Ohta

    Full Text Available Epidermal melanocytes play an important role in protecting the skin from UV rays, and their functional impairment results in pigment disorders. Additionally, melanomas are considered to arise from mutations that accumulate in melanocyte stem cells. The mechanisms underlying melanocyte differentiation and the defining characteristics of melanocyte stem cells in humans are, however, largely unknown. In the present study, we set out to generate melanocytes from human iPS cells in vitro, leading to a preliminary investigation of the mechanisms of human melanocyte differentiation. We generated iPS cell lines from human dermal fibroblasts using the Yamanaka factors (SOX2, OCT3/4, and KLF4, with or without c-MYC. These iPS cell lines were subsequently used to form embryoid bodies (EBs and then differentiated into melanocytes via culture supplementation with Wnt3a, SCF, and ET-3. Seven weeks after inducing differentiation, pigmented cells expressing melanocyte markers such as MITF, tyrosinase, SILV, and TYRP1, were detected. Melanosomes were identified in these pigmented cells by electron microscopy, and global gene expression profiling of the pigmented cells showed a high similarity to that of human primary foreskin-derived melanocytes, suggesting the successful generation of melanocytes from iPS cells. This in vitro differentiation system should prove useful for understanding human melanocyte biology and revealing the mechanism of various pigment cell disorders, including melanoma.

  17. Virtual microstructural leaf tissue generation based on cell growth modeling

    NARCIS (Netherlands)

    Abera, M.K.; Retta, M.A.; Verboven, P.; Nicolai, B.M.; Berghuijs, H.; Struik, P.

    2016-01-01

    A cell growth algorithm for virtual leaf tissue generation is presented based on the biomechanics of plant cells in tissues. The algorithm can account for typical differences in epidermal layers, palisade mesophyll layer and spongy mesophyll layer which have characteristic differences in the shap

  18. Multiple-octave spanning mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    CERN Document Server

    Zhou, Binbin

    2016-01-01

    Bright and broadband coherent mid-IR radiation is important for exciting and probing molecular vibrations. Using cascaded nonlinearities in conventional quadratic nonlinear crystal like lithium niobate, self-defocusing near-IR solitons have been demonstrated that led to very broadband supercontinuum generation in the visible, near-IR and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal pumped in the mid-IR gives multiple-octave spanning supercontinua. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed (covering 1.6-$7.0~\\mu$m). The results were recorded in a commercially available crystal LiInS$_2$ pumped in the 3-$4~\\mu$m range, but other mid-IR crystals ...

  19. Experimental and Therapeutic Opportunities for Stem Cells in Multiple Sclerosis

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    Rickie Patani

    2012-11-01

    Full Text Available Multiple Sclerosis (MS is an inflammatory demyelinating neurodegenerative disorder of the brain and spinal cord that causes significant disability in young adults. Although the precise aetiopathogenesis of MS remains unresolved, its pathological hallmarks include inflammation, demyelination, axonal injury (acute and chronic, astrogliosis and variable remyelination. Despite major recent advances in therapeutics for the early stage of the disease there are currently no disease modifying treatments for the progressive stage of disease, whose pathological substrate is axonal degeneration. This represents the great and unmet clinical need in MS. Against this background, human stem cells offer promise both to improve understanding of disease mechanism(s through in-vitro modeling as well as potentially direct use to supplement and promote remyelination, an endogenous reparative process where entire myelin sheaths are restored to demyelinated axons. Conceptually, stem cells can act directly to myelinate axons or indirectly through different mechanisms to promote endogenous repair; importantly these two mechanisms of action are not mutually exclusive. We propose that discovery of novel methods to invoke or enhance remyelination in MS may be the most effective therapeutic strategy to limit axonal damage and instigate restoration of structure and function in this debilitating condition. Human stem cell derived neurons and glia, including patient specific cells derived through reprogramming, provide an unprecedented experimental system to model MS “in a dish” as well as enable high-throughput drug discovery. Finally, we speculate upon the potential role for stem cell based therapies in MS.

  20. Nestin Reporter Transgene Labels Multiple Central Nervous System Precursor Cells

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    Avery S. Walker

    2010-01-01

    Full Text Available Embryonic neuroepithelia and adult subventricular zone (SVZ stem and progenitor cells express nestin. We characterized a transgenic line that expresses enhanced green fluorescent protein (eGFP specified to neural tissue by the second intronic enhancer of the nestin promoter that had several novel features. During embryogenesis, the dorsal telencephalon contained many and the ventral telencephalon few eGFP+ cells. eGFP+ cells were found in postnatal and adult neurogenic regions. eGFP+ cells in the SVZ expressed multiple phenotype markers, glial fibrillary acidic protein, Dlx, and neuroblast-specific molecules suggesting the transgene is expressed through the lineage. eGFP+ cell numbers increased in the SVZ after cortical injury, suggesting this line will be useful in probing postinjury neurogenesis. In non-neurogenic regions, eGFP was strongly expressed in oligodendrocyte progenitors, but not in astrocytes, even when they were reactive. This eGFP+ mouse will facilitate studies of proliferative neuroepithelia and adult neurogenesis, as well as of parenchymal oligodendrocytes.

  1. Mechanism for multiplicity of steady states with distinct cell concentration in continuous culture of mammalian cells.

    Science.gov (United States)

    Yongky, Andrew; Lee, Jongchan; Le, Tung; Mulukutla, Bhanu Chandra; Daoutidis, Prodromos; Hu, Wei-Shou

    2015-07-01

    Continuous culture for the production of biopharmaceutical proteins offers the possibility of steady state operations and thus more consistent product quality and increased productivity. Under some conditions, multiplicity of steady states has been observed in continuous cultures of mammalian cells, wherein with the same dilution rate and feed nutrient composition, steady states with very different cell and product concentrations may be reached. At those different steady states, cells may exhibit a high glycolysis flux with high lactate production and low cell concentration, or a low glycolysis flux with low lactate and high cell concentration. These different steady states, with different cell concentration, also have different productivity. Developing a mechanistic understanding of the occurrence of steady state multiplicity and devising a strategy to steer the culture toward the desired steady state is critical. We establish a multi-scale kinetic model that integrates a mechanistic intracellular metabolic model and cell growth model in a continuous bioreactor. We show that steady state multiplicity exists in a range of dilution rate in continuous culture as a result of the bistable behavior in glycolysis. The insights from the model were used to devise strategies to guide the culture to the desired steady state in the multiple steady state region. The model provides a guideline principle in the design of continuous culture processes of mammalian cells.

  2. Generation of Partially Reprogrammed Cells and Fully Reprogrammed iPS Cells by Plasmid Transfection.

    Science.gov (United States)

    Kim, Jong Soo; Choi, Hyun Woo; Hong, Yean Ju; Do, Jeong Tae

    2016-01-01

    Induced pluripotent stem (iPS) cells can be directly generated from somatic cells by overexpression of defined transcription factors. iPS cells can perpetually self-renew and differentiate into all cell types of an organism. iPS cells were first generated through infection with retroviruses that contain reprogramming factors. However, development of an exogene-free iPS cell generation method is crucial for future therapeutic applications, because integrated exogenes result in the formation of tumors in chimeras and regain pluripotency after differentiation in vitro. Here, we describe a method to generate iPS cells by transfection of plasmid vectors and to convert partially reprogrammed cells into fully reprogrammed iPS cells by switching from mouse ESC culture conditions to KOSR-based media with bFGF. We also describe basic methods used to characterize fully reprogrammed iPS cells.

  3. Induced pluripotent stem cells, from generation to application: review article

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    Sharif Moradi

    2014-11-01

    Full Text Available Embryonic stem cells are pluripotent stem cells which have the ability to indefinitely self-renew and differentiate into all differentiated cells of the body. Regarding their two main properties (unlimited self-renewal and multi-lineage differentiation, these cells have various biomedical applications in basic research and cell based therapy. Because the transplantation of differentiated cells that are derived from embryonic stem cells is allogenic, they face the problem of immune rejection following the transplantation of embryonic stem cell-derived cells into patients. In 2006, researchers from Japan reported the derivation of a new type of pluripotent stem cells which could overcome the problem of immune rejection that is associated with the application of embryonic stem cells. They designated these cells as induced pluripotent stem (iPS cells, because their production was ‘induced’ from differentiated somatic cells using a combination of four embryonic stem cell-associated transcription factors. Importantly, these pluripotent stem cells exhibit all the key features of embryonic stem cells including unlimited self-renewal and multi-lineage differentiation potential, and can pass the most stringent test of pluripotency which is known as the tetraploid (4n complementation. Hence, in addition to bypassing the problem of immune rejection, iPS cells have all of the potential applications of embryonic stem cells, including in developmental studies, toxicology research, drug discovery and disease modeling. Also, considering that they could be generated from patient’s own cells, iPS cells hold great promise in the future of patient-specific cell replacement therapies using pluripotent stem cells. In this review article, we will present a comprehensive review on the how and why of the generation of iPS cell from somatic cells of the body and discuss how they should be characterized in terms of morphologically, pluripotent stem cell behavior, and

  4. Activation of endogenous neural stem cells for multiple sclerosis therapy

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    Iliana eMichailidou

    2015-01-01

    Full Text Available Multiple sclerosis (MS is a chronic inflammatory disorder of the central nervous system, leading to severe neurological deficits. Current MS treatment regimens, consist of immunomodulatory agents aiming to reduce the rate of relapses. However, these agents are usually insufficient to treat chronic neurological disability.A promising perspective for future therapy of MS is the regeneration of lesions with replacement of the damaged oligodendrocytes or neurons. Therapies targeting to the enhancement of endogenous remyelination, aim to promote the activation of either the parenchymal oligodendrocyte progenitor cells or the subventricular zone-derived neural stem cells (NSCs. Less studied but highly potent, is the strategy of neuronal regeneration with endogenous NSCs that although being linked to numerous limitations, is anticipated to ameliorate cognitive disability in MS. Focusing on the forebrain, this review highlights the role of NSCs in the regeneration of MS lesions.

  5. Hepatic failure caused by plasma cell infiltration in multiple Myeloma

    Institute of Scientific and Technical Information of China (English)

    Fadi E Rahhal; Robert R Schade; Asha Nayak; Teresa A Coleman

    2009-01-01

    Although plasma cell infiltration is not rare in autopsy of patients with multiple myeloma (MM), it is very rarely detected in living patients. This is because MM rarely causes significant liver dysfunction that requires further evaluation. A 49-year-old man presented with acute renal failure and was diagnosed with kappa light chain MM stage ?B. Thalidomide and dexamethasone were initiated. The patient developed a continuous increase in bilirubin that led to severe cholestasis. A liver biopsy revealed plasma cell infiltration. He then rapidly progressed to liver failure and died. Treatment options are limited in MM with significant liver dysfunction.Despite new drug therapies in MM, those patients with rapidly progressive liver failure appear to have a dismal outcome.

  6. A BAC-bacterial recombination method to generate physically linked multiple gene reporter DNA constructs

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    Gong Shiaochin

    2009-03-01

    Full Text Available Abstract Background Reporter gene mice are valuable animal models for biological research providing a gene expression readout that can contribute to cellular characterization within the context of a developmental process. With the advancement of bacterial recombination techniques to engineer reporter gene constructs from BAC genomic clones and the generation of optically distinguishable fluorescent protein reporter genes, there is an unprecedented capability to engineer more informative transgenic reporter mouse models relative to what has been traditionally available. Results We demonstrate here our first effort on the development of a three stage bacterial recombination strategy to physically link multiple genes together with their respective fluorescent protein (FP reporters in one DNA fragment. This strategy uses bacterial recombination techniques to: (1 subclone genes of interest into BAC linking vectors, (2 insert desired reporter genes into respective genes and (3 link different gene-reporters together. As proof of concept, we have generated a single DNA fragment containing the genes Trap, Dmp1, and Ibsp driving the expression of ECFP, mCherry, and Topaz FP reporter genes, respectively. Using this DNA construct, we have successfully generated transgenic reporter mice that retain two to three gene readouts. Conclusion The three stage methodology to link multiple genes with their respective fluorescent protein reporter works with reasonable efficiency. Moreover, gene linkage allows for their common chromosomal integration into a single locus. However, the testing of this multi-reporter DNA construct by transgenesis does suggest that the linkage of two different genes together, despite their large size, can still create a positional effect. We believe that gene choice, genomic DNA fragment size and the presence of endogenous insulator elements are critical variables.

  7. Generation of antigen-specific T cell immunity through T cell receptor gene transfer

    NARCIS (Netherlands)

    Coccoris, Miriam

    2009-01-01

    Cancer cells often escape the attack of immune cells because they originate from self-tissue. Through T cell receptor gene transfer it is possible to equip peripheral T cells with a desired specificity, and this strategy may be useful to generate tumor-specific T cells for the treatment of cancer in

  8. Generation of induced pluripotent stem cells from human blood.

    Science.gov (United States)

    Loh, Yuin-Han; Agarwal, Suneet; Park, In-Hyun; Urbach, Achia; Huo, Hongguang; Heffner, Garrett C; Kim, Kitai; Miller, Justine D; Ng, Kitwa; Daley, George Q

    2009-05-28

    Human dermal fibroblasts obtained by skin biopsy can be reprogrammed directly to pluripotency by the ectopic expression of defined transcription factors. Here, we describe the derivation of induced pluripotent stem cells from CD34+ mobilized human peripheral blood cells using retroviral transduction of OCT4/SOX2/KLF4/MYC. Blood-derived human induced pluripotent stem cells are indistinguishable from human embryonic stem cells with respect to morphology, expression of surface antigens, and pluripotency-associated transcription factors, DNA methylation status at pluripotent cell-specific genes, and the capacity to differentiate in vitro and in teratomas. The ability to reprogram cells from human blood will allow the generation of patient-specific stem cells for diseases in which the disease-causing somatic mutations are restricted to cells of the hematopoietic lineage.

  9. NANOG priming before full reprogramming may generate germ cell tumours

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    I Grad

    2011-11-01

    Full Text Available Reprogramming somatic cells into a pluripotent state brings patient-tailored, ethical controversy-free cellular therapy closer to reality. However, stem cells and cancer cells share many common characteristics; therefore, it is crucial to be able to discriminate between them. We generated two induced pluripotent stem cell (iPSC lines, with NANOG pre-transduction followed by OCT3/4, SOX2, and LIN28 overexpression. One of the cell lines, CHiPS W, showed normal pluripotent stem cell characteristics, while the other, CHiPS A, though expressing pluripotency markers, failed to differentiate and gave rise to germ cell-like tumours in vivo. Comparative genomic hybridisation analysis of the generated iPS lines revealed that they were genetically more stable than human embryonic stem cell counterparts. This analysis proved to be predictive for the differentiation potential of analysed cells. Moreover, the CHiPS A line expressed a lower ratio of p53/p21 when compared to CHiPS W. NANOG pre-induction followed by OCT3/4, SOX2, MYC, and KLF4 induction resulted in the same tumour-inducing phenotype. These results underline the importance of a re-examination of the role of NANOG during reprogramming. Moreover, this reprogramming method may provide insights into primordial cell tumour formation and cancer stem cell transformation.

  10. Generation of iPS Cells from Human Peripheral Blood Mononuclear Cells Using Episomal Vectors.

    Science.gov (United States)

    Su, Ruijun Jeanna; Neises, Amanda; Zhang, Xiao-Bing

    2016-01-01

    Peripheral blood is the easy-to-access, minimally invasive, and the most abundant cell source to use for cell reprogramming. The episomal vector is among the best approaches for generating integration-free induced pluripotent stem (iPS) cells due to its simplicity and affordability. Here we describe the detailed protocol for the efficient generation of integration-free iPS cells from peripheral blood mononuclear cells. With this optimized protocol, one can readily generate hundreds of iPS cell colonies from 1 ml of peripheral blood.

  11. Real-Time Terrain Storage Generation from Multiple Sensors towards Mobile Robot Operation Interface

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    Wei Song

    2014-01-01

    Full Text Available A mobile robot mounted with multiple sensors is used to rapidly collect 3D point clouds and video images so as to allow accurate terrain modeling. In this study, we develop a real-time terrain storage generation and representation system including a nonground point database (PDB, ground mesh database (MDB, and texture database (TDB. A voxel-based flag map is proposed for incrementally registering large-scale point clouds in a terrain model in real time. We quantize the 3D point clouds into 3D grids of the flag map as a comparative table in order to remove the redundant points. We integrate the large-scale 3D point clouds into a nonground PDB and a node-based terrain mesh using the CPU. Subsequently, we program a graphics processing unit (GPU to generate the TDB by mapping the triangles in the terrain mesh onto the captured video images. Finally, we produce a nonground voxel map and a ground textured mesh as a terrain reconstruction result. Our proposed methods were tested in an outdoor environment. Our results show that the proposed system was able to rapidly generate terrain storage and provide high resolution terrain representation for mobile mapping services and a graphical user interface between remote operators and mobile robots.

  12. Real-time terrain storage generation from multiple sensors towards mobile robot operation interface.

    Science.gov (United States)

    Song, Wei; Cho, Seoungjae; Xi, Yulong; Cho, Kyungeun; Um, Kyhyun

    2014-01-01

    A mobile robot mounted with multiple sensors is used to rapidly collect 3D point clouds and video images so as to allow accurate terrain modeling. In this study, we develop a real-time terrain storage generation and representation system including a nonground point database (PDB), ground mesh database (MDB), and texture database (TDB). A voxel-based flag map is proposed for incrementally registering large-scale point clouds in a terrain model in real time. We quantize the 3D point clouds into 3D grids of the flag map as a comparative table in order to remove the redundant points. We integrate the large-scale 3D point clouds into a nonground PDB and a node-based terrain mesh using the CPU. Subsequently, we program a graphics processing unit (GPU) to generate the TDB by mapping the triangles in the terrain mesh onto the captured video images. Finally, we produce a nonground voxel map and a ground textured mesh as a terrain reconstruction result. Our proposed methods were tested in an outdoor environment. Our results show that the proposed system was able to rapidly generate terrain storage and provide high resolution terrain representation for mobile mapping services and a graphical user interface between remote operators and mobile robots.

  13. HAIR CELL-LIKE CELL GENERATION INDUCED BY NATURE CULTURE OF ADULT RAT AUDITORY EPITHELIUM

    Institute of Scientific and Technical Information of China (English)

    Liu Hui; Zhu Hongliang; Li Shengli; Yao Xiaobao; Wang Xiaoxia

    2006-01-01

    Objective To establish adult rat auditory epithelial cell culture and try to find precursor cells of auditory hair cells in vitro. Methods With refinement of culture media and techniques, cochlear sensory epithelial cells of adult rat were cultured. Immunocytochemistry and Bromodeoxyuridine (BrdU)labeling were used to detect properties and mitotic status of cultured cells. Results The cultured auditory epithelial cells showed a large, flat epithelial morphotype and expressed F-actin and cytokeratin, a subset of cells generated from auditory epithelium were labeled by calretinin, a specific marker of early hair cell. Conclusion Adult rat auditory epithelium can be induced to generate hair cell-like cells by nature culture, this phenomenon suggests that progenitor cells may exist in rat cochlea and they may give birth to new hair cells. Whether these progenitor cells are tissue specific stem cells is still need more study.

  14. Efficient and rapid derivation of primitive neural stem cells and generation of brain subtype neurons from human pluripotent stem cells.

    Science.gov (United States)

    Yan, Yiping; Shin, Soojung; Jha, Balendu Shekhar; Liu, Qiuyue; Sheng, Jianting; Li, Fuhai; Zhan, Ming; Davis, Janine; Bharti, Kapil; Zeng, Xianmin; Rao, Mahendra; Malik, Nasir; Vemuri, Mohan C

    2013-11-01

    Human pluripotent stem cells (hPSCs), including human embryonic stem cells and human induced pluripotent stem cells, are unique cell sources for disease modeling, drug discovery screens, and cell therapy applications. The first step in producing neural lineages from hPSCs is the generation of neural stem cells (NSCs). Current methods of NSC derivation involve the time-consuming, labor-intensive steps of an embryoid body generation or coculture with stromal cell lines that result in low-efficiency derivation of NSCs. In this study, we report a highly efficient serum-free pluripotent stem cell neural induction medium that can induce hPSCs into primitive NSCs (pNSCs) in 7 days, obviating the need for time-consuming, laborious embryoid body generation or rosette picking. The pNSCs expressed the neural stem cell markers Pax6, Sox1, Sox2, and Nestin; were negative for Oct4; could be expanded for multiple passages; and could be differentiated into neurons, astrocytes, and oligodendrocytes, in addition to the brain region-specific neuronal subtypes GABAergic, dopaminergic, and motor neurons. Global gene expression of the transcripts of pNSCs was comparable to that of rosette-derived and human fetal-derived NSCs. This work demonstrates an efficient method to generate expandable pNSCs, which can be further differentiated into central nervous system neurons and glia with temporal, spatial, and positional cues of brain regional heterogeneity. This method of pNSC derivation sets the stage for the scalable production of clinically relevant neural cells for cell therapy applications in good manufacturing practice conditions.

  15. Detection and Characterization of Circulating Tumour Cells in Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Liangxuan Zhang

    2016-06-01

    Full Text Available Multiple myeloma (MM remains an incurable disease despite recent therapeutic improvements. The ability to detect and characterize MM circulating tumour cells (CTCs in peripheral blood provides an alternative to replace or augment invasive bone marrow (BM biopsies with a simple blood draw, providing real-time, clinically relevant information leading to improved disease manage‐ ment and therapy selection. Here we have developed and qualified an enrichment-free, cell-based immunofluores‐ cence MM CTC assay that utilizes an automated digital pathology algorithm to distinguish MM CTCs from white blood cells (WBCs on the basis of CD138 and CD45 expression levels, as well as a number of morphological parameters. These MM CTCs were further characterized for expression of phospho-ribosomal protein S6 (pS6 as a readout for PI3K/AKT pathway activation. Clinical feasi‐ bility of the assay was established by testing blood samples from a small cohort of patients, where we detected popu‐ lations of both CD138pos and CD138neg MM CTCs. In this study, we developed an immunofluorescent cell-based assay to detect and characterize CTCs in MM.

  16. Endothelial progenitor cells display clonal restriction in multiple myeloma

    Directory of Open Access Journals (Sweden)

    Dai Kezhi

    2006-06-01

    Full Text Available Abstract Background In multiple myeloma (MM, increased neoangiogenesis contributes to tumor growth and disease progression. Increased levels of endothelial progenitor cells (EPCs contribute to neoangiogenesis in MM, and, importantly, covary with disease activity and response to treatment. In order to understand the mechanisms responsible for increased EPC levels and neoangiogenic function in MM, we investigated whether these cells were clonal by determining X-chromosome inactivation (XCI patterns in female patients by a human androgen receptor assay (HUMARA. In addition, EPCs and bone marrow cells were studied for the presence of clonotypic immunoglobulin heavy-chain (IGH gene rearrangement, which indicates clonality in B cells; thus, its presence in EPCs would indicate a close genetic link between tumor cells in MM and endothelial cells that provide tumor neovascularization. Methods A total of twenty-three consecutive patients who had not received chemotherapy were studied. Screening in 18 patients found that 11 displayed allelic AR in peripheral blood mononuclear cells, and these patients were further studied for XCI patterns in EPCs and hair root cells by HUMARA. In 2 patients whose EPCs were clonal by HUMARA, and in an additional 5 new patients, EPCs were studied for IGH gene rearrangement using PCR with family-specific primers for IGH variable genes (VH. Results In 11 patients, analysis of EPCs by HUMARA revealed significant skewing (≥ 77% expression of a single allele in 64% (n = 7. In 4 of these patients, XCI skewing was extreme (≥ 90% expression of a single allele. In contrast, XCI in hair root cells was random. Furthermore, PCR amplification with VH primers resulted in amplification of the same product in EPCs and bone marrow cells in 71% (n = 5 of 7 patients, while no IGH rearrangement was found in EPCs from healthy controls. In addition, in patients with XCI skewing in EPCs, advanced age was associated with poorer clinical status

  17. The highly conserved human cytomegalovirus UL136 ORF generates multiple Golgi-localizing protein isoforms through differential translation initiation.

    Science.gov (United States)

    Liao, Huanan; Lee, Jung-Hyun; Kondo, Rikita; Katata, Marei; Imadome, Ken-Ichi; Miyado, Kenji; Inoue, Naoki; Fujiwara, Shigeyoshi; Nakamura, Hiroyuki

    2014-01-22

    The UL133-UL138 locus in the unique long b' (ULb') region of the human cytomegalovirus (HCMV) genome is considered to play certain roles in viral replication, dissemination and latency in a host cell type-dependent manner. Here we characterized the proteins encoded by UL136, one of the open reading frames (ORFs) in the locus. Comparative sequence analysis of UL136 among clinical isolates and laboratory strains indicates that its predicted amino-acid sequence is highly conserved. A polyclonal antibody against UL136 proteins (pUL136s) was raised against its carboxy-terminal region and this antibody specifically recognized at least five UL136-encoded protein isoforms of 29-17 kDa both in HCMV-infected cells and in cells transfected with a construct expressing pUL136. Immunofluorescence analysis with this antibody revealed localization of pUL136 in the Golgi apparatus. Analysis of several pUL136 mutants indicated that the putative transmembrane domain of pUL136 is required for its Golgi localization. Mutational analysis of multiple AUG codons in UL136 demonstrated that translation initiation from these AUG codons contributes in the generation of pUL136 isoforms.

  18. Fuel cell power generation system. Nenryo denchi hatsuden system

    Energy Technology Data Exchange (ETDEWEB)

    Sato, M.; Shiba, Y.

    1993-06-11

    It is general to fabricate the primary cooling water system including the fuel cell main body using corrosion resistant stainless steel, while the secondary cooling system including absorption type freezer is made of carbon steel. For this structure, returning the cooling water of the secondary cooling system to the primary cooling system can cause the corrosion of the primary cooling system. That is, the water of inferior quality in the secondary system can corrode the primary system including the fuel cell. This invention solves the problem. The fuel cell bypass which is branched from the fuel cell cooling water inlet, detours the fuel cell, and it is connected to the water-vapor separator installed to the fuel cell. And the heat exchanger is installed at any of fuel cooling water outlet line, fuel cell cooling water inlet line, or fuel cell bypass line. With this structure, recovering the heat generated during the power generation by the fuel cell at the secondary side of the heat exchanger can be achieved while separating the primary and secondary cooling water. So that the trouble of fuel cell operation caused by the contamination of the primary cooling water with the secondary cooling water which contains corrosive impurities can be avoided. 6 figs.

  19. Fourier optics along a hybrid optical fiber for Bessel-like beam generation and its applications in multiple-particle trapping.

    Science.gov (United States)

    Kim, Jongki; Jeong, Yoonseob; Lee, Sejin; Ha, Woosung; Shin, Jeon-Soo; Oh, Kyunghwan

    2012-02-15

    Highly efficient Bessel-like beam generation was achieved based on a new all-fiber method that implements Fourier transformation of a micro annular aperture along a concatenated composite optical fiber. The beam showed unique characteristics of tilted washboard optical potential in the transverse plane and sustained a nondiffracting length over 400 μm along the axial direction. Optical trapping of multiple dielectric particles and living Jurkat cells were successfully demonstrated along the axial direction of the beam in the water.

  20. Efficiency dip observed with InGaN-based multiple quantum well solar cells

    KAUST Repository

    Lai, Kunyu

    2014-01-01

    The dip of external quantum efficiency (EQE) is observed on In0.15Ga0.85N/GaN multiple quantum well (MQW) solar cells upon the increase of incident optical power density. With indium composition increased to 25%, the EQE dip becomes much less noticeable. The composition dependence of EQE dip is ascribed to the competition between radiative recombination and photocurrent generation in the active region, which are dictated by quantum-confined Stark effect (QCSE) and composition fluctuation in the MQWs.

  1. Simple and inexpensive microfluidic devices for the generation of monodisperse multiple emulsions

    KAUST Repository

    Li, Erqiang

    2013-12-16

    Droplet-based microfluidic devices have become a preferred versatile platform for various fields in physics, chemistry and biology. Polydimethylsiloxane soft lithography, the mainstay for fabricating microfluidic devices, usually requires the usage of expensive apparatus and a complex manufacturing procedure. Here, we report the design and fabrication of simple and inexpensive microfluidic devices based on microscope glass slides and pulled glass capillaries, for generating monodisperse multiple emulsions. The advantages of our method lie in a simple manufacturing procedure, inexpensive processing equipment and flexibility in the surface modification of the designed microfluidic devices. Different types of devices have been designed and tested and the experimental results demonstrated their robustness for preparing monodisperse single, double, triple and multi-component emulsions. © 2014 IOP Publishing Ltd.

  2. A novel generation scheme of ultra-short pulse trains with multiple wavelengths

    Science.gov (United States)

    Su, Yulong; Hu, Hui; Feng, Huan; Li, Lu; Han, Biao; Wen, Yu; Wang, Yishan; Si, Jinhai; Xie, Xiaoping; Wang, Weiqiang

    2017-04-01

    We demonstrate a novel scheme based on active mode locking combined with four-wave mixing (FWM) to generate ultra-short pulse trains at high repetition rate with multiple wavelengths for applications in various fields. The obtained six wavelengths display high uniformity both in temporal and frequency domain. Pulses at each wavelength are mode locked with pulse duration of 44.37 ps, signal-to-noise ratio (SNR) of 47.89 dB, root-mean-square (RMS) timing jitter of 552.7 fs, and the time-bandwidth product of 0.68 at repetition rate of 1 GHz. The experimental results show this scheme has promising usage in optical communications, optical networks, and fiber sensing.

  3. Infrared Supercontinuum Generation in Multiple Quantum Well Nanostructures under Electromagnetically Induced Transparency

    CERN Document Server

    Borgohain, Nitu; Konar, S

    2015-01-01

    Mid-infrared spectral broadening is of great scientific and technological interest, which till date is mainly achieved using non-silica glass fibers, primarily made of tellurite, fluoride and chalcogenide glasses. We investigate broadband mid-infrared supercontinuum generation at very low power in semiconductor multiple quantum well (MQW) systems facilitated by electromagnetically induced transparency. 100 femto-seconds pulses of peak power close to a Watt have been launched in the electromagnetically induced transparency window of a 30 period 1.374 {\\mu}m long MQW system. Broadband supercontinuum spectra, attributed to self phase modulation and modulation instability, is achievable at the end of the MQW system. The central part of the spectra is dominated by several dips and the far infra-red part of the spectra is more broadened in comparison to the infra-red portion. Key advantage of the proposed scheme is that the supercontinuum source could be easily integrated with other semiconductor devices.

  4. Molecular diagnostics of a single drug-resistant multiple myeloma case using targeted next-generation sequencing

    Directory of Open Access Journals (Sweden)

    Ikeda H

    2015-10-01

    Full Text Available Hiroshi Ikeda,1 Kazuya Ishiguro,1 Tetsuyuki Igarashi,1 Yuka Aoki,1 Toshiaki Hayashi,1 Tadao Ishida,1 Yasushi Sasaki,1,2 Takashi Tokino,2 Yasuhisa Shinomura1 1Department of Gastroenterology, Rheumatology and Clinical Immunology, 2Medical Genome Sciences, Research Institute for Frontier Medicine, Sapporo Medical University, Sapporo, Japan Abstract: A 69-year-old man was diagnosed with IgG λ-type multiple myeloma (MM, Stage II in October 2010. He was treated with one cycle of high-dose dexamethasone. After three cycles of bortezomib, the patient exhibited slow elevations in the free light-chain levels and developed a significant new increase of serum M protein. Bone marrow cytogenetic analysis revealed a complex karyotype characteristic of malignant plasma cells. To better understand the molecular pathogenesis of this patient, we sequenced for mutations in the entire coding regions of 409 cancer-related genes using a semiconductor-based sequencing platform. Sequencing analysis revealed eight nonsynonymous somatic mutations in addition to several copy number variants, including CCND1 and RB1. These alterations may play roles in the pathobiology of this disease. This targeted next-generation sequencing can allow for the prediction of drug resistance and facilitate improvements in the treatment of MM patients. Keywords: multiple myeloma, drug resistance, genome-wide sequencing, semiconductor sequencer, target therapy

  5. Generating a non-integrating human induced pluripotent stem cell bank from urine-derived cells.

    Directory of Open Access Journals (Sweden)

    Yanting Xue

    Full Text Available Induced pluripotent stem cell (iPS cell holds great potential for applications in regenerative medicine, drug discovery, and disease modeling. We describe here a practical method to generate human iPS cells from urine-derived cells (UCs under feeder-free, virus-free, serum-free condition and without oncogene c-MYC. We showed that this approach could be applied in a large population with different genetic backgrounds. UCs are easily accessible and exhibit high reprogramming efficiency, offering advantages over other cell types used for the purpose of iPS generation. Using the approach described in this study, we have generated 93 iPS cell lines from 20 donors with diverse genetic backgrounds. The non-viral iPS cell bank with these cell lines provides a valuable resource for iPS cells research, facilitating future applications of human iPS cells.

  6. Multiple Roles of MYC in Integrating Regulatory Networks of Pluripotent Stem Cells

    Science.gov (United States)

    Fagnocchi, Luca; Zippo, Alessio

    2017-01-01

    Pluripotent stem cells (PSCs) are defined by their self-renewal potential, which permits their unlimited propagation, and their pluripotency, being able to generate cell of the three embryonic lineages. These properties render PSCs a valuable tool for both basic and medical research. To induce and stabilize the pluripotent state, complex circuitries involving signaling pathways, transcription regulators and epigenetic mechanisms converge on a core transcriptional regulatory network of PSCs, thus determining their cell identity. Among the transcription factors, MYC represents a central hub, which modulates and integrates multiple mechanisms involved both in the maintenance of pluripotency and in cell reprogramming. Indeed, it instructs the PSC-specific cell cycle, metabolism and epigenetic landscape, contributes to limit exit from pluripotency and modulates signaling cascades affecting the PSC identity. Moreover, MYC extends its regulation on pluripotency by controlling PSC-specific non-coding RNAs. In this report, we review the MYC-controlled networks, which support the pluripotent state and discuss how their perturbation could affect cell identity. We further discuss recent finding demonstrating a central role of MYC in triggering epigenetic memory in PSCs, which depends on the establishment of a WNT-centered self-reinforcing circuit. Finally, we comment on the therapeutic implications of the role of MYC in affecting PSCs. Indeed, PSCs are used for both disease and cancer modeling and to derive cells for regenerative medicine. For these reasons, unraveling the MYC-mediated mechanism in those cells is fundamental to exploit their full potential and to identify therapeutic targets. PMID:28217689

  7. Bruceantin inhibits multiple myeloma cancer stem cell proliferation.

    Science.gov (United States)

    Issa, Mark E; Berndt, Sarah; Carpentier, Gilles; Pezzuto, John M; Cuendet, Muriel

    2016-09-01

    Multiple myeloma (MM) continues to claim the lives of a majority of patients. MM cancer stem cells (CSCs) have been demonstrated to sustain tumor growth. Due to their ability to self-renew and to express detoxifying enzymes and efflux transporters, MM-CSCs are rendered highly resistant to conventional therapies. Therefore, managing MM-CSCs characteristics could have profound clinical implications. Bruceantin (BCT) is a natural product previously demonstrated to inhibit the growth of MM in RPMI 8226 cells-inoculated mouse xenograft models, and to cause regression in already established tumors. The objectives of the present study were to test the inhibitory effects of BCT on MM-CSCs growth derived from a human primary tumor, and to explore a mechanism of action underlying these effects. BCT exhibited potent antiproliferative activity in MM-CSCs starting at 25 nM. BCT induced cell cycle arrest, cell death and apoptosis in MM-CSCs as well as inhibited cell migration and angiogenesis in vitro. Using a qPCR screen, it was found that the gene expression of a number of Notch pathway members was altered. Pretreatment of MM-CSCs with the γ-secretase inhibitor RO4929097, a Notch pathway inhibitor, reversed BCT-induced effects on MM-CSCs proliferation. In this study, BCT was shown to be an effective agent in controlling the proliferation, viability and migration of MM-CSCs as well as angiogenesis in vitro. The effect on MM-CSCs proliferation may be mediated by the Notch pathway. These results warrant further investigation of BCT in a broader set of human-derived MM-CSCs and with in vivo models representative of MM.

  8. Economical analysis of combined fuel cell generators and absorption chillers

    Directory of Open Access Journals (Sweden)

    M. Morsy El-Gohary

    2013-06-01

    Full Text Available This paper presents a co-generation system based on combined heat and power for commercial units. For installation of a co-generation system, certain estimates for this site should be performed through making assessments of electrical loads, domestic water, and thermal demand. This includes domestic hot water, selection of the type of power generator, fuel cell, and the type of air conditioning system, and absorption chillers. As a matter of fact, the co-generation system has demonstrated good results for both major aspects, economic and environmental. From the environmental point of view, this can be considered as an ideal solution for problems concerned with the usage of Chlorofluoro carbons. On the other hand, from the economic point of view, the cost analysis has revealed that the proposed system saves 4% of total cost through using the co-generation system.

  9. Generation of a Reconfigurable Logical Cell Using Evolutionary Computation

    Directory of Open Access Journals (Sweden)

    I. Campos-Cantón

    2013-01-01

    Full Text Available In nature, an interesting topic is about how a cell can be reconfigured in order to achieve a different task. Another interesting topic is about the learning process that seems to be a trial and error process. In this work, we present mechanisms about how to produce a reconfigurable logical cell based on the tent map. The reconfiguration is realized by modifying its internal parameters generating several logical functions in the same structure. The logical cell is built with three blocks: the initial condition generating function, the tent map, and the output function. Furthermore, we propose a reconfigurable structure based on a chaotic system and an evolutionary algorithm is used in order to tune the parameters of the cell via trial and error process.

  10. Random number generation deficits in patients with multiple sclerosis: Characteristics and neural correlates.

    Science.gov (United States)

    Geisseler, Olivia; Pflugshaupt, Tobias; Buchmann, Andreas; Bezzola, Ladina; Reuter, Katja; Schuknecht, Bernhard; Weller, David; Linnebank, Michael; Brugger, Peter

    2016-09-01

    Human subjects typically deviate systematically from randomness when attempting to produce a sequence of random numbers. Despite an increasing number of behavioral and functional neuroimaging studies on random number generation (RNG), its structural correlates have never been investigated. We set out to fill this gap in 44 patients with multiple sclerosis (MS), a disease whose impact on RNG has never been studied. The RNG task required the paced (1 Hz) generation of the numbers from 1 to 6 in a sequence as random as possible. The same task was administered in 39 matched healthy controls. To assess neuroanatomical correlates such as cortical thickness, lesion load and third ventricle width, all subjects underwent high-resolution structural MRI. Compared to controls, MS patients exhibited an enhanced tendency to arrange consecutive numbers in an ascending order ("forward counting"). Furthermore, patients showed a higher susceptibility to rule breaks (producing out-of-category digits like 7) and to skip beats of the metronome. Clinico-anatomical correlation analyses revealed two main findings: First, increased counting in MS patients was associated with higher cortical lesion load. Second, increased number of skipped beats was related to widespread cortical thinning. In conclusion, our test results illustrate a loss of behavioral complexity in the course of MS, while the imaging results suggest an association between this loss and cortical pathology.

  11. Study on the regulatory approach of KNGR multiple steam generator tube rupture events

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Keun Sun; Kweon, Y. C.; Lee, S. J.; Lee, Y. S.; Cheong, D. Y.; Park, T. J.; Lee, M. G.; Cheon, Y. H. [Sunmoon Univ., Asan (Korea, Republic of); Cheong, J. H. [Baekseok College of Cultural Studies, Cheonan (Korea, Republic of)

    2001-10-15

    The scope and contents performed in this project are as follows : firstly, reviews of the structure and contents of local and foreign regulatory requirements as well as analysis of design features related to safety improvement and containment bypass during multiple steam generator tube failure of advanced reactors of domestic and foreign countries. Secondly, analyses of the state-of-the-art of the development of local and foreign regulatory requirements, research trends, design features and safety goals of advanced reactors, especially for technical issues related to the containment bypass during MSGTR event. Thirdly, analyses of the event of MSGTR for the KNGR using MAS 1.4 which is the best-estimate system code developed by Korea Atomic Energy Research Institute. Errors in input-decks established last year have been corrected during this analysis. Fourthly, assessment of the effects of several parameters on the consequences following a MSGTR event. Tube rupture location, selection of affected steam generator, tube modeling method, discharge coefficient (C{sub D}) are examined. Fifthly, establishment of regulatory direction of technical issues related to the containment bypass during MSGTR event.

  12. Peer generation of multiple-choice questions: student engagement and experiences.

    Science.gov (United States)

    Rhind, Susan M; Pettigrew, Graham W

    2012-01-01

    A free online system for generation of multiple-choice questions (PeerWise) was implemented in three courses (course A, B, and C) in two different years (second and third year) of a veterinary degree program. Students were asked to author questions, and answer and rate each other's questions. Student experiences of the system were explored using an online survey. The majority of students in both years either agreed or strongly agreed that both authoring and answering questions was helpful for their studies and wanted to use the system again in future courses. Thematic analysis highlighted students' views that engaging with the resource increased breadth and depth of knowledge and understanding and was very useful for revision purposes. There was a statistically significant difference between students in second and third year regarding whether students felt it was necessary for academic staff to be involved in the review process. Thematic analysis of this aspect identified issues relating to confidence in the ability of the peer group and the need for reassurance in the second-year group. Student engagement with the system was correlated with examination performance. In courses A and B there was a positive correlation between number of questions answered and examination performance, in course C there was no correlation. This study highlights the benefits of peer activity around question generation and proposes that such activities are an efficient and effective means to support student learning.

  13. Generation of induced pluripotent stem cells from human β-thalassemia fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    Yixuan Wang; Yonghua Jiang; Sheng Liu; Xiaofang Sun; Shaorong Gao

    2009-01-01

    @@ Dear Editor, Induced pluripotent stem (iPS) cells have recently been generated by directly introducing several transcrip-tion factors into differentiated human somatic cells, and these iPS cells show great similarities to embryo-derived ES cells [1-3].

  14. A prototypic microfluidic platform generating stepwise concentration gradients for real-time study of cell apoptosis.

    Science.gov (United States)

    Dai, Wen; Zheng, Yizhe; Luo, Kathy Qian; Wu, Hongkai

    2010-04-16

    This work describes the development of a prototypic microfluidic platform for the generation of stepwise concentration gradients of drugs. A sensitive apoptotic analysis method is integrated into this microfluidic system for studying apoptosis of HeLa cells under the influence of anticancer drug, etoposide, with various concentrations in parallel; it measures the yellow fluorescent proteincyan fluorescent protein fluorescence resonance energy transfer (FRET) signal that responds to the activation of caspase-3, an indicator of cell apoptosis. Sets of microfluidic valves on the chip generate stepwise concentration gradient of etoposide in various cell-culture microchambers. The FRET signals from multiple chambers are simultaneously monitored under a fluorescent microscope for long-time observation and the on-chip results are compared with those from 96-well plate study and the methylthiazolyldiphenyl-tetrazolium bromide (MTT) assay. The microfluidic platform shows several advantages including high-throughput capacity, low drug consumption, and high sensitivity.

  15. Mesenchymal stem cells and induced pluripotent stem cells as therapies for multiple sclerosis.

    Science.gov (United States)

    Xiao, Juan; Yang, Rongbing; Biswas, Sangita; Qin, Xin; Zhang, Min; Deng, Wenbin

    2015-04-24

    Multiple sclerosis (MS) is a chronic, autoimmune, inflammatory demyelinating disorder of the central nervous system that leads to permanent neurological deficits. Current MS treatment regimens are insufficient to treat the irreversible neurological disabilities. Tremendous progress in the experimental and clinical applications of cell-based therapies has recognized stem cells as potential candidates for regenerative therapy for many neurodegenerative disorders including MS. Mesenchymal stem cells (MSC) and induced pluripotent stem cell (iPSCs) derived precursor cells can modulate the autoimmune response in the central nervous system (CNS) and promote endogenous remyelination and repair process in animal models. This review highlights studies involving the immunomodulatory and regenerative effects of mesenchymal stem cells and iPSCs derived cells in animal models, and their translation into immunomodulatory and neuroregenerative treatment strategies for MS.

  16. Mesenchymal Stem Cells and Induced Pluripotent Stem Cells as Therapies for Multiple Sclerosis

    Directory of Open Access Journals (Sweden)

    Juan Xiao

    2015-04-01

    Full Text Available Multiple sclerosis (MS is a chronic, autoimmune, inflammatory demyelinating disorder of the central nervous system that leads to permanent neurological deficits. Current MS treatment regimens are insufficient to treat the irreversible neurological disabilities. Tremendous progress in the experimental and clinical applications of cell-based therapies has recognized stem cells as potential candidates for regenerative therapy for many neurodegenerative disorders including MS. Mesenchymal stem cells (MSC and induced pluripotent stem cell (iPSCs derived precursor cells can modulate the autoimmune response in the central nervous system (CNS and promote endogenous remyelination and repair process in animal models. This review highlights studies involving the immunomodulatory and regenerative effects of mesenchymal stem cells and iPSCs derived cells in animal models, and their translation into immunomodulatory and neuroregenerative treatment strategies for MS.

  17. Lack of resistance development in Bemisia tabaci to Isaria fumosorosea after multiple generations of selection

    Science.gov (United States)

    Gao, Tianni; Wang, Zhaolei; Huang, Yü; Keyhani, Nemat O.; Huang, Zhen

    2017-02-01

    The emergence of insecticide resistant insect pests is of significant concern worldwide. The whitefly, Bemisia tabaci, is an important agricultural pest and has shown incredible resilience developing resistance to a number of chemical pesticides. Entomopathogenic fungi such as Isaria fumosorosea offer an attractive alternative to chemical pesticides for insect control, and this fungus has been shown to be an effective pathogen of B. tabaci. Little is known concerning the potential for the development of resistance to I. fumosorosea by B. tabaci. Five generations of successive survivors of B. tabaci infected by I. fumosorosea were assayed with I. fumosorosea. No significant differences in susceptibility to I. fumosorosea, number of ovarioles, or ovipostioning were seen between any of the generations tested. Effects of I. fumosorosea and cell-free ethyl acetate fractions derived from the fungus on the B. tabaci fat body, ovary, and vitellogenin were also investigated. These data revealed significant deformation and degradation of ovary tissues and associated vitellogenin by the fungal mycelium as well as by cell-free ethyl acetate fungal extracts. These data indicate the lack of the emergence of resistance to I. fumosorosea under the conditions tested and demonstrate invasion of the insect reproductive tissues during fungal infection.

  18. Lack of resistance development in Bemisia tabaci to Isaria fumosorosea after multiple generations of selection

    Science.gov (United States)

    Gao, Tianni; Wang, Zhaolei; Huang, Yü; Keyhani, Nemat O.; Huang, Zhen

    2017-01-01

    The emergence of insecticide resistant insect pests is of significant concern worldwide. The whitefly, Bemisia tabaci, is an important agricultural pest and has shown incredible resilience developing resistance to a number of chemical pesticides. Entomopathogenic fungi such as Isaria fumosorosea offer an attractive alternative to chemical pesticides for insect control, and this fungus has been shown to be an effective pathogen of B. tabaci. Little is known concerning the potential for the development of resistance to I. fumosorosea by B. tabaci. Five generations of successive survivors of B. tabaci infected by I. fumosorosea were assayed with I. fumosorosea. No significant differences in susceptibility to I. fumosorosea, number of ovarioles, or ovipostioning were seen between any of the generations tested. Effects of I. fumosorosea and cell-free ethyl acetate fractions derived from the fungus on the B. tabaci fat body, ovary, and vitellogenin were also investigated. These data revealed significant deformation and degradation of ovary tissues and associated vitellogenin by the fungal mycelium as well as by cell-free ethyl acetate fungal extracts. These data indicate the lack of the emergence of resistance to I. fumosorosea under the conditions tested and demonstrate invasion of the insect reproductive tissues during fungal infection. PMID:28230074

  19. Peripheral NK cell phenotypes: multiple changing of faces of an adapting, developing cell.

    Science.gov (United States)

    Perussia, Bice; Chen, Yingying; Loza, Matthew J

    2005-02-01

    We have defined the existence of developmental relationships among human peripheral NK cells with distinct phenotypic and functional characteristics. These findings closely parallel the changes that occur in vivo during NK cell development, and in vitro in experimental culture systems supporting NK cell generation from hematopoietic progenitors. These new insights provide a simplified framework to understand NK cell immunobiology and the cellular bases for their roles in innate immunity, initiation and maintenance of immune responses via regulation of adaptive and accessory cell functions, and immune pathologies.

  20. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    David Deangelis; Rich Depuy; Debashis Dey; Georgia Karvountzi; Nguyen Minh; Max Peter; Faress Rahman; Pavel Sokolov; Deliang Yang

    2004-09-30

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) during the April to October 2004 reporting period in Task 2.3 (SOFC Scaleup for Hybrid and Fuel Cell Systems) under Cooperative Agreement DE-FC26-01NT40779 for the U. S. Department of Energy, National Energy Technology Laboratory (DOE/NETL), entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. This study analyzes the performance and economics of power generation systems for central power generation application based on Solid Oxide Fuel Cell (SOFC) technology and fueled by natural gas. The main objective of this task is to develop credible scale up strategies for large solid oxide fuel cell-gas turbine systems. System concepts that integrate a SOFC with a gas turbine were developed and analyzed for plant sizes in excess of 20 MW. A 25 MW plant configuration was selected with projected system efficiency of over 65% and a factory cost of under $400/kW. The plant design is modular and can be scaled to both higher and lower plant power ratings. Technology gaps and required engineering development efforts were identified and evaluated.

  1. CIF2Cell: Generating geometries for electronic structure programs

    Science.gov (United States)

    Björkman, Torbjörn

    2011-05-01

    The CIF2Cell program generates the geometrical setup for a number of electronic structure programs based on the crystallographic information in a Crystallographic Information Framework (CIF) file. The program will retrieve the space group number, Wyckoff positions and crystallographic parameters, make a sensible choice for Bravais lattice vectors (primitive or principal cell) and generate all atomic positions. Supercells can be generated and alloys are handled gracefully. The code currently has output interfaces to the electronic structure programs ABINIT, CASTEP, CPMD, Crystal, Elk, Exciting, EMTO, Fleur, RSPt, Siesta and VASP. Program summaryProgram title: CIF2Cell Catalogue identifier: AEIM_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEIM_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: GNU GPL version 3 No. of lines in distributed program, including test data, etc.: 12 691 No. of bytes in distributed program, including test data, etc.: 74 933 Distribution format: tar.gz Programming language: Python (versions 2.4-2.7) Computer: Any computer that can run Python (versions 2.4-2.7) Operating system: Any operating system that can run Python (versions 2.4-2.7) Classification: 7.3, 7.8, 8 External routines: PyCIFRW [1] Nature of problem: Generate the geometrical setup of a crystallographic cell for a variety of electronic structure programs from data contained in a CIF file. Solution method: The CIF file is parsed using routines contained in the library PyCIFRW [1], and crystallographic as well as bibliographic information is extracted. The program then generates the principal cell from symmetry information, crystal parameters, space group number and Wyckoff sites. Reduction to a primitive cell is then performed, and the resulting cell is output to suitably named files along with documentation of the information source generated from any bibliographic information contained in the CIF

  2. Multiple Sclerosis: Pathogenesis, Symptoms, Diagnoses and Cell-Based Therapy

    Directory of Open Access Journals (Sweden)

    Nazem Ghasemi,

    2017-01-01

    Full Text Available Multiple sclerosis (MS is a chronic inflammatory disease characterized by central nervous system (CNS lesions that can lead to severe physical or cognitive disability as well as neurological defects. Although the etiology and pathogenesis of MS remains unclear, the present documents illustrate that the cause of MS is multifactorial and include genetic predisposition together with environmental factors such as exposure to infectious agents, vitamin deficiencies, and smoking. These agents are able to trigger a cascade of events in the immune system which lead to neuronal cell death accompanied by nerve demyelination and neuronal dysfunction. Conventional therapies for MS are based on the use of anti-inflammatory and immunomodulatory drugs, but these treatments are not able to stop the destruction of nerve tissue. Thus, other strategies such as stem cell transplantation have been proposed for the treatment of MS. Overall, it is important that neurologists be aware of current information regarding the pathogenesis, etiology, diagnostic criteria, and treatment of MS. Thus, this issue has been discussed according to recent available information.

  3. Dendritic Cells and Multiple Sclerosis: Disease, Tolerance and Therapy

    Directory of Open Access Journals (Sweden)

    Mohammad G. Mohammad

    2012-12-01

    Full Text Available Multiple sclerosis (MS is a devastating neurological disease that predominantly affects young adults resulting in severe personal and economic impact. The majority of therapies for this disease were developed in, or are beneficial in experimental autoimmune encephalomyelitis (EAE, the animal model of MS. While known to target adaptive anti-CNS immune responses, they also target, the innate immune arm. This mini-review focuses on the role of dendritic cells (DCs, the professional antigen presenting cells of the innate immune system. The evidence for a role for DCs in the appropriate regulation of anti-CNS autoimmune responses and their role in MS disease susceptibility and possible therapeutic utility are discussed. Additionally, the current controversy regarding the evidence for the presence of functional DCs in the normal CNS is reviewed. Furthermore, the role of CNS DCs and potential routes of their intercourse between the CNS and cervical lymph nodes are considered. Finally, the future role that this nexus between the CNS and the cervical lymph nodes might play in site directed molecular and cellular therapy for MS is outlined.

  4. Single cell functional analysis of multiple myeloma cell populations correlates with diffusion profiles in static microfluidic coculture systems.

    Science.gov (United States)

    Moore, Thomas A; Young, Edmond W K

    2016-07-01

    Microfluidic cell culture systems are becoming increasingly useful for studying biology questions, particularly those involving small cell populations that are cultured within microscale geometries mimicking the complex cellular microenvironment. Depending on the geometry and spatial organization of these cell populations, however, paracrine signaling between cell types can depend critically on spatial concentration profiles of soluble factors generated by diffusive transport. In scenarios where single cell data are acquired to study cell population heterogeneities in functional response, uncertainty associated with concentration profiles can lead to interpretation bias. To address this issue and provide important evidence on how diffusion develops within typical microfluidic cell culture systems, a combination of experimental and computational approaches were applied to measure and predict concentration patterns within microfluidic geometries, and characterize the functional response of culture cells based on single-cell resolution transcription factor activation. Using a model coculture system consisting of multiple myeloma cells (MMCs) and neighboring bone marrow stromal cells (BMSCs), we measured concentrations of three cytokines (IL-6, VEGF, and TNF-α) in conditioned media collected from separate culture compartments using a multiplex ELISA system. A 3D numerical model was developed to predict biomolecular diffusion and resulting concentration profiles within the tested microsystems and compared with experimental diffusion of 20 kDa FITC-Dextran. Finally, diffusion was further characterized by controlling exogenous IL-6 diffusion and the coculture spatial configuration of BMSCs to stimulate STAT3 nuclear translocation in MMCs. Results showed agreement between numerical and experimental results, provided evidence of a shallow concentration gradient across the center well of the microsystem that did not lead to a bias in results, and demonstrated that

  5. Large-scale generation of cell-derived nanovesicles

    Science.gov (United States)

    Jo, W.; Kim, J.; Yoon, J.; Jeong, D.; Cho, S.; Jeong, H.; Yoon, Y. J.; Kim, S. C.; Gho, Y. S.; Park, J.

    2014-09-01

    Exosomes are enclosed compartments that are released from cells and that can transport biological contents for the purpose of intercellular communications. Research into exosomes is hindered by their rarity. In this article, we introduce a device that uses centrifugal force and a filter with micro-sized pores to generate a large quantity of cell-derived nanovesicles. The device has a simple polycarbonate structure to hold the filter, and operates in a common centrifuge. Nanovesicles are similar in size and membrane structure to exosomes. Nanovesicles contain intracellular RNAs ranging from microRNA to mRNA, intracellular proteins, and plasma membrane proteins. The quantity of nanovesicles produced using the device is 250 times the quantity of naturally secreted exosomes. Also, the quantity of intracellular contents in nanovesicles is twice that in exosomes. Nanovesicles generated from murine embryonic stem cells can transfer RNAs to target cells. Therefore, this novel device and the nanovesicles that it generates are expected to be used in exosome-related research, and can be applied in various applications such as drug delivery and cell-based therapy.

  6. CD138-negative clonogenic cells are plasma cells but not B cells in some multiple myeloma patients.

    Science.gov (United States)

    Hosen, N; Matsuoka, Y; Kishida, S; Nakata, J; Mizutani, Y; Hasegawa, K; Mugitani, A; Ichihara, H; Aoyama, Y; Nishida, S; Tsuboi, A; Fujiki, F; Tatsumi, N; Nakajima, H; Hino, M; Kimura, T; Yata, K; Abe, M; Oka, Y; Oji, Y; Kumanogoh, A; Sugiyama, H

    2012-09-01

    Clonogenic multiple myeloma (MM) cells reportedly lacked expression of plasma cell marker CD138. It was also shown that CD19(+) clonotypic B cells can serve as MM progenitor cells in some patients. However, it is unclear whether CD138-negative clonogenic MM plasma cells are identical to clonotypic CD19(+) B cells. We found that in vitro MM colony-forming cells were enriched in CD138(-)CD19(-)CD38(++) plasma cells, while CD19(+) B cells never formed MM colonies in 16 samples examined in this study. We next used the SCID-rab model, which enables engraftment of human MM in vivo. CD138(-)CD19(-)CD38(++) plasma cells engrafted in this model rapidly propagated MM in 3 out of 9 cases, while no engraftment of CD19(+) B cells was detected. In 4 out of 9 cases, CD138(+) plasma cells propagated MM, although more slowly than CD138(-) cells. Finally, we transplanted CD19(+) B cells from 13 MM patients into NOD/SCID IL2Rγc(-/-) mice, but MM did not develop. These results suggest that at least in some MM patients CD138-negative clonogenic cells are plasma cells rather than B cells, and that MM plasma cells including CD138(-) and CD138(+) cells have the potential to propagate MM clones in vivo in the absence of CD19(+) B cells.

  7. Tunicamycin promotes apoptosis in leukemia cells through ROS generation and downregulation of survivin expression.

    Science.gov (United States)

    Lim, Eun Jin; Heo, Jeonghoon; Kim, Young-Ho

    2015-08-01

    Tunicamycin (TN), one of the endoplasmic reticulum stress inducers, has been reported to inhibit tumor cell growth and exhibit anticarcinogenic activity. However, the mechanism by which TN initiates apoptosis remains poorly understood. In the present study, we investigated the effect of TN on the apoptotic pathway in U937 cells. We show that TN induces apoptosis in association with caspase-3 activation, generation of reactive oxygen species (ROS), and downregulation of survivin expression. P38 MAPK (mitogen-activated protein kinase) and the generation of ROS signaling pathway play crucial roles in TN-induced apoptosis in U937 cells. We hypothesized that TN-induced activation of p38 MAPK signaling pathway is responsible for cell death. To test this hypothesis, we selectively inhibited MAPK during treatment with TN. Our data demonstrated that inhibitor of p38 (SB), but not ERK (PD) or JNK (SP), partially maintained apoptosis during treatment with TN. Pre-treatment with NAC and GSH markedly prevented cell death, suggesting a role for ROS in this process. Ectopic expression of survivin in U937 cells attenuated TN-induced apoptosis by suppression of caspase-3 cleavage, mitochondrial membrane potential, and cytochrome c release in U937 cells. Taken together, our results show that TN modulates multiple components of the apoptotic response of human leukemia cells and raise the possibility of a novel therapeutic strategy for hematological malignancies.

  8. Development of a Recombination System for the Generation of Occlusion Positive Genetically Modified Anticarsia Gemmatalis Multiple Nucleopolyhedrovirus

    Directory of Open Access Journals (Sweden)

    Santiago Haase

    2015-03-01

    Full Text Available Anticarsia gemmatalis is an important pest in legume crops in South America and it has been successfully controlled using Anticarsia gemmatalis Multiple Nucleopolyhedrovirus (AgMNPV in subtropical climate zones. Nevertheless, in temperate climates its speed of kill is too slow. Taking this into account, genetic modification of AgMNPV could lead to improvements of its biopesticidal properties. Here we report the generation of a two-component system that allows the production of recombinant AgMNPV. This system is based on a parental AgMNPV in which the polyhedrin gene (polh was replaced by a bacterial β-galactosidase (lacZ gene flanked by two target sites for the homing endonuclease I-PpoI. Co-transfection of insect cells with linearized (I-PpoI-digested parental genome and a transfer vector allowed the restitution of polh and the expression of a heterologous gene upon homologous recombination, with a low background of non-recombinant AgMNPV. The system was validated by constructing a recombinant occlusion-positive (polh+ AgMNPV expressing the green fluorescent protein gene (gfp. This recombinant virus infected larvae normally per os and led to the expression of GFP in cell culture as well as in A. gemmatalis larvae. These results demonstrate that the system is an efficient method for the generation of recombinant AgMNPV expressing heterologous genes, which can be used for manifold purposes, including biotechnological and pharmaceutical applications and the production of orally infectious recombinants with improved biopesticidal properties.

  9. Generation of induced pluripotent stem cells from human cord blood.

    Science.gov (United States)

    Haase, Alexandra; Olmer, Ruth; Schwanke, Kristin; Wunderlich, Stephanie; Merkert, Sylvia; Hess, Christian; Zweigerdt, Robert; Gruh, Ina; Meyer, Johann; Wagner, Stefan; Maier, Lars S; Han, Dong Wook; Glage, Silke; Miller, Konstantin; Fischer, Philipp; Schöler, Hans R; Martin, Ulrich

    2009-10-02

    Induced pluripotent stem cells (iPSCs) may represent an ideal cell source for future regenerative therapies. A critical issue concerning the clinical use of patient-specific iPSCs is the accumulation of mutations in somatic (stem) cells over an organism's lifetime. Acquired somatic mutations are passed onto iPSCs during reprogramming and may be associated with loss of cellular functions and cancer formation. Here we report the generation of human iPSCs from cord blood (CB) as a juvenescent cell source. CBiPSCs show characteristics typical of embryonic stem cells and can be differentiated into derivatives of all three germ layers, including functional cardiomyocytes. For future therapeutic production of autologous and allogeneic iPSC derivatives, CB could be routinely harvested for public and commercial CB banks without any donor risk. CB could readily become available for pediatric patients and, in particular, for newborns with genetic diseases or congenital malformations.

  10. MicroRNAs targeting TGFβ signalling underlie the regulatory T cell defect in multiple sclerosis.

    Science.gov (United States)

    Severin, Mary E; Lee, Priscilla W; Liu, Yue; Selhorst, Amanda J; Gormley, Matthew G; Pei, Wei; Yang, Yuhong; Guerau-de-Arellano, Mireia; Racke, Michael K; Lovett-Racke, Amy E

    2016-06-01

    Transforming growth factor beta (TGFβ) signalling is critical for regulatory T cell development and function, and regulatory T cell dysregulation is a common observation in autoimmune diseases, including multiple sclerosis. In a comprehensive miRNA profiling study of patients with multiple sclerosis naïve CD4 T cells, 19 differentially expressed miRNAs predicted to target the TGFβ signalling pathway were identified, leading to the hypothesis that miRNAs may be responsible for the regulatory T cell defect observed in patients with multiple sclerosis. Patients with multiple sclerosis had reduced levels of TGFβ signalling components in their naïve CD4 T cells. The differentially expressed miRNAs negatively regulated the TGFβ pathway, resulting in a reduced capacity of naïve CD4 T cells to differentiate into regulatory T cells. Interestingly, the limited number of regulatory T cells, that did develop when these TGFβ-targeting miRNAs were overexpressed, were capable of suppressing effector T cells. As it has previously been demonstrated that compromising TGFβ signalling results in a reduced regulatory T cell repertoire insufficient to control autoimmunity, and patients with multiple sclerosis have a reduced regulatory T cell repertoire, these data indicate that the elevated expression of multiple TGFβ-targeting miRNAs in naïve CD4 T cells of patients with multiple sclerosis impairs TGFβ signalling, and dampens regulatory T cell development, thereby enhancing susceptibility to developing multiple sclerosis.

  11. Thymoquinone causes multiple effects, including cell death, on dividing plant cells.

    Science.gov (United States)

    Hassanien, Sameh E; Ramadan, Ahmed M; Azeiz, Ahmed Z Abdel; Mohammed, Rasha A; Hassan, Sabah M; Shokry, Ahmed M; Atef, Ahmed; Kamal, Khalid B H; Rabah, Samar; Sabir, Jamal S M; Abuzinadah, Osama A; El-Domyati, Fotouh M; Martin, Gregory B; Bahieldin, Ahmed

    2013-01-01

    Thymoquinone (TQ) is a major constituent of Nigella sativa oil with reported anti-oxidative activity and anti-inflammatory activity in animal cells. It also inhibits proliferation and induces programmed cell death (apoptosis) in human skin cancer cells. The present study sought to detect the influence of TQ on dividing cells of three plant systems and on expression of Bcl2-associated athanogene-like (BAG-like) genes that might be involved during the process of cell death. BAG genes are known for the regulation of diverse physiological processes in animals, including apoptosis, tumorigenesis, stress responses, and cell division. Synthetic TQ at 0.1mg/mL greatly reduced wheat seed germination rate, whereas 0.2mg/mL completely inhibited germination. An Evans blue assay revealed moderate cell death in the meristematic zone of Glycine max roots after 1h of TQ treatment (0.2mg/mL), with severe cell death occurring in this zone after 2h of treatment. Light microscopy of TQ-treated (0.2mg/mL) onion hairy root tips for 1h revealed anti-mitotic activity and also cell death-associated changes, including nuclear membrane disruption and nuclear fragmentation. Transmission electron microscopy of TQ-treated cells (0.2mg/mL) for 1h revealed shrinkage of the plasma membrane, leakage of cell lysate, degradation of cell walls, enlargement of vacuoles and condensation of nuclei. Expression of one BAG-like gene, previously associated with cell death, was induced 20 min after TQ treatment in Glycine max root tip cells. Thus, TQ has multiple effects, including cell death, on dividing plant cells and plants may serve as a useful system to further investigate the mechanisms underlying the response of eukaryotic cells to TQ.

  12. Generation of stomach tissue from mouse embryonic stem cells.

    Science.gov (United States)

    Noguchi, Taka-aki K; Ninomiya, Naoto; Sekine, Mari; Komazaki, Shinji; Wang, Pi-Chao; Asashima, Makoto; Kurisaki, Akira

    2015-08-01

    Successful pluripotent stem cell differentiation methods have been developed for several endoderm-derived cells, including hepatocytes, β-cells and intestinal cells. However, stomach lineage commitment from pluripotent stem cells has remained a challenge, and only antrum specification has been demonstrated. We established a method for stomach differentiation from embryonic stem cells by inducing mesenchymal Barx1, an essential gene for in vivo stomach specification from gut endoderm. Barx1-inducing culture conditions generated stomach primordium-like spheroids, which differentiated into mature stomach tissue cells in both the corpus and antrum by three-dimensional culture. This embryonic stem cell-derived stomach tissue (e-ST) shared a similar gene expression profile with adult stomach, and secreted pepsinogen as well as gastric acid. Furthermore, TGFA overexpression in e-ST caused hypertrophic mucus and gastric anacidity, which mimicked Ménétrier disease in vitro. Thus, in vitro stomach tissue derived from pluripotent stem cells mimics in vivo development and can be used for stomach disease models.

  13. In vitro expanded stem cells from the developing retina fail to generate photoreceptors but differentiate into myelinating oligodendrocytes.

    Directory of Open Access Journals (Sweden)

    Magdalena Czekaj

    Full Text Available Cell transplantation to treat retinal degenerative diseases represents an option for the replacement of lost photoreceptor cells. In vitro expandable cells isolated from the developing mammalian retina have been suggested as a potential source for the generation of high numbers of donor photoreceptors. In this study we used standardized culture conditions based on the presence of the mitogens FGF-2 and EGF to generate high numbers of cells in vitro from the developing mouse retina. These presumptive 'retinal stem cells' ('RSCs' can be propagated as monolayer cultures over multiple passages, express markers of undifferentiated neural cells, and generate neuronal and glial cell types upon withdrawal of mitogens in vitro or following transplantation into the adult mouse retina. The proportion of neuronal differentiation can be significantly increased by stepwise removal of mitogens and inhibition of the notch signaling pathway. However, 'RSCs', by contrast to their primary counterparts in vivo, i.e. retinal progenitor cells, loose the expression of retina-specific progenitor markers like Rax and Chx10 after passaging and fail to differentiate into photoreceptors both in vitro or after intraretinal transplantation. Notably, 'RSCs' can be induced to differentiate into myelinating oligodendrocytes, a cell type not generated by primary retinal progenitor cells. Based on these findings we conclude that 'RSCs' expanded in high concentrations of FGF-2 and EGF loose their retinal identity and acquire features of in vitro expandable neural stem-like cells making them an inappropriate cell source for strategies aimed at replacing photoreceptor cells in the degenerated retina.

  14. In vitro expanded stem cells from the developing retina fail to generate photoreceptors but differentiate into myelinating oligodendrocytes.

    Science.gov (United States)

    Czekaj, Magdalena; Haas, Jochen; Gebhardt, Marlen; Müller-Reichert, Thomas; Humphries, Peter; Farrar, Jane; Bartsch, Udo; Ader, Marius

    2012-01-01

    Cell transplantation to treat retinal degenerative diseases represents an option for the replacement of lost photoreceptor cells. In vitro expandable cells isolated from the developing mammalian retina have been suggested as a potential source for the generation of high numbers of donor photoreceptors. In this study we used standardized culture conditions based on the presence of the mitogens FGF-2 and EGF to generate high numbers of cells in vitro from the developing mouse retina. These presumptive 'retinal stem cells' ('RSCs') can be propagated as monolayer cultures over multiple passages, express markers of undifferentiated neural cells, and generate neuronal and glial cell types upon withdrawal of mitogens in vitro or following transplantation into the adult mouse retina. The proportion of neuronal differentiation can be significantly increased by stepwise removal of mitogens and inhibition of the notch signaling pathway. However, 'RSCs', by contrast to their primary counterparts in vivo, i.e. retinal progenitor cells, loose the expression of retina-specific progenitor markers like Rax and Chx10 after passaging and fail to differentiate into photoreceptors both in vitro or after intraretinal transplantation. Notably, 'RSCs' can be induced to differentiate into myelinating oligodendrocytes, a cell type not generated by primary retinal progenitor cells. Based on these findings we conclude that 'RSCs' expanded in high concentrations of FGF-2 and EGF loose their retinal identity and acquire features of in vitro expandable neural stem-like cells making them an inappropriate cell source for strategies aimed at replacing photoreceptor cells in the degenerated retina.

  15. The Generation of Human Induced Pluripotent Stem Cells from Blood Cells: An Efficient Protocol Using Serial Plating of Reprogrammed Cells by Centrifugation

    Directory of Open Access Journals (Sweden)

    Youngkyun Kim

    2016-01-01

    Full Text Available Human induced pluripotent stem cells (hiPSCs have demonstrated great potential for differentiation into diverse tissues. We report a straightforward and highly efficient method for the generation of iPSCs from PBMCs. By plating the cells serially to a newly coated plate by centrifugation, this protocol provides multiple healthy iPSC colonies even from a small number of PBMCs. The generated iPSCs expressed pluripotent markers and differentiated into all three germ layer lineages. The protocol can also be used with umbilical cord blood mononuclear cells (CBMCs. In this study, we present a simple and efficient protocol that improved the yield of iPSCs from floating cells such as PBMCs and CBMCs by serial plating and centrifugation.

  16. The Generation of Human Induced Pluripotent Stem Cells from Blood Cells: An Efficient Protocol Using Serial Plating of Reprogrammed Cells by Centrifugation.

    Science.gov (United States)

    Kim, Youngkyun; Rim, Yeri Alice; Yi, Hyoju; Park, Narae; Park, Sung-Hwan; Ju, Ji Hyeon

    2016-01-01

    Human induced pluripotent stem cells (hiPSCs) have demonstrated great potential for differentiation into diverse tissues. We report a straightforward and highly efficient method for the generation of iPSCs from PBMCs. By plating the cells serially to a newly coated plate by centrifugation, this protocol provides multiple healthy iPSC colonies even from a small number of PBMCs. The generated iPSCs expressed pluripotent markers and differentiated into all three germ layer lineages. The protocol can also be used with umbilical cord blood mononuclear cells (CBMCs). In this study, we present a simple and efficient protocol that improved the yield of iPSCs from floating cells such as PBMCs and CBMCs by serial plating and centrifugation.

  17. Urine excretion strategy for stem cell-generated embryonic kidneys

    Science.gov (United States)

    Yokote, Shinya; Matsunari, Hitomi; Iwai, Satomi; Yamanaka, Shuichiro; Uchikura, Ayuko; Fujimoto, Eisuke; Matsumoto, Kei; Nagashima, Hiroshi; Kobayashi, Eiji; Yokoo, Takashi

    2015-01-01

    There have been several recent attempts to generate, de novo, a functional whole kidney from stem cells using the organogenic niche or blastocyst complementation methods. However, none of these attempts succeeded in constructing a urinary excretion pathway for the stem cell-generated embryonic kidney. First, we transplanted metanephroi from cloned pig fetuses into gilts; the metanephroi grew to about 3 cm and produced urine, although hydronephrosis eventually was observed because of the lack of an excretion pathway. Second, we demonstrated the construction of urine excretion pathways in rats. Rat metanephroi or metanephroi with bladders (developed from cloacas) were transplanted into host rats. Histopathologic analysis showed that tubular lumina dilation and interstitial fibrosis were reduced in kidneys developed from cloacal transplants compared with metanephroi transplantation. Then we connected the host animal’s ureter to the cloacal-developed bladder, a technique we called the “stepwise peristaltic ureter” (SWPU) system. The application of the SWPU system avoided hydronephrosis and permitted the cloacas to differentiate well, with cloacal urine being excreted persistently through the recipient ureter. Finally, we demonstrated a viable preclinical application of the SWPU system in cloned pigs. The SWPU system also inhibited hydronephrosis in the pig study. To our knowledge, this is the first report showing that the SWPU system may resolve two important problems in the generation of kidneys from stem cells: construction of a urine excretion pathway and continued growth of the newly generated kidney. PMID:26392557

  18. Human CD8 T cells generated in vitro from hematopoietic stem cells are functionally mature

    Directory of Open Access Journals (Sweden)

    Zúñiga-Pflücker Juan

    2011-03-01

    Full Text Available Abstract Background T cell development occurs within the highly specialized thymus. Cytotoxic CD8 T cells are critical in adaptive immunity by targeting virally infected or tumor cells. In this study, we addressed whether functional CD8 T cells can be generated fully in vitro using human umbilical cord blood (UCB hematopoietic stem cells (HSCs in coculture with OP9-DL1 cells. Results HSC/OP9-DL1 cocultures supported the differentiation of CD8 T cells, which were TCR/CD3hi CD27hi CD1aneg and thus phenotypically resembled mature functional CD8 single positive thymocytes. These in vitro-generated T cells also appeared to be conventional CD8 cells, as they expressed high levels of Eomes and low levels of Plzf, albeit not identical to ex vivo UCB CD8 T cells. Consistent with the phenotypic and molecular characterization, upon TCR-stimulation, in vitro-generated CD8 T cells proliferated, expressed activation markers (MHC-II, CD25, CD38, secreted IFN-γ and expressed Granzyme B, a cytotoxic T-cell effector molecule. Conclusion Taken together, the ability to direct human hematopoietic stem cell or T-progenitor cells towards a mature functional phenotype raises the possibility of establishing cell-based treatments for T-immunodeficiencies by rapidly restoring CD8 effector function, thereby mitigating the risks associated with opportunistic infections.

  19. The Aryl Hydrocarbon Receptor Antagonist StemRegenin1 Improves In Vitro Generation of Highly Functional Natural Killer Cells from CD34(+) Hematopoietic Stem and Progenitor Cells.

    Science.gov (United States)

    Roeven, Mieke W H; Thordardottir, Soley; Kohela, Arwa; Maas, Frans; Preijers, Frank; Jansen, Joop H; Blijlevens, Nicole M; Cany, Jeannette; Schaap, Nicolaas; Dolstra, Harry

    2015-12-15

    Early natural killer (NK)-cell repopulation after allogeneic stem cell transplantation (allo-SCT) has been associated with reduced relapse rates without an increased risk of graft-versus-host disease, indicating that donor NK cells have specific antileukemic activity. Therefore, adoptive transfer of donor NK cells is an attractive strategy to reduce relapse rates after allo-SCT. Since NK cells of donor origin will not be rejected, multiple NK-cell infusions could be administered in this setting. However, isolation of high numbers of functional NK cells from transplant donors is challenging. Hence, we developed a cytokine-based ex vivo culture protocol to generate high numbers of functional NK cells from granulocyte colony-stimulating factor (G-CSF)-mobilized CD34(+) hematopoietic stem and progenitor cells (HSPCs). In this study, we demonstrate that addition of aryl hydrocarbon receptor antagonist StemRegenin1 (SR1) to our culture protocol potently enhances expansion of CD34(+) HSPCs and induces expression of NK-cell-associated transcription factors promoting NK-cell differentiation. As a result, high numbers of NK cells with an active phenotype can be generated using this culture protocol. These SR1-generated NK cells exert efficient cytolytic activity and interferon-γ production toward acute myeloid leukemia and multiple myeloma cells. Importantly, we observed that NK-cell proliferation and function are not inhibited by cyclosporin A, an immunosuppressive drug often used after allo-SCT. These findings demonstrate that SR1 can be exploited to generate high numbers of functional NK cells from G-CSF-mobilized CD34(+) HSPCs, providing great promise for effective NK-cell-based immunotherapy after allo-SCT.

  20. Dynamics of fragmentation and multiple vacancy generation in irradiated single-walled carbon nanotubes

    CERN Document Server

    Javeed, Sumera; Ahmad, Shoaib

    2016-01-01

    The results from mass spectrometry of clusters sputtered from Cs+ irradiated single-walled carbon nano-tubes (SWCNTs) as a function of energy and dose identify the nature of the resulting damage in the form of multiple vacancy generation. For pristine SWCNTs at all Cs+ energies, C2 is the most dominant species, followed by C3, C4 and C1. The experiments were performed in three stages: in the first stage, Cs+ energy E(Cs+) was varied. During the second stage, the nanotubes were irradiated continuously at E(Cs+) = 5 keV for 1,800 s. Afterwards, the entire sequence of irradiation energies was repeated to differentiate between the fragmentation patterns of the pristine and of heavily irradiated SWCNTs. The sputtering and normalized yields identify the quantitative and relative extent of the ion-induced damage by creating double, triple and quadruple vacancies; the single vacancies are least favored. Sputtering from the heavily irradiated SWCNTs occurs not only from the damaged and fragmented nanotubes, but also f...

  1. Multiple surface DBD electrode system for efficient and controlled generation of ozone

    Science.gov (United States)

    Prukner, Vaclav; Hoffer, Petr; Simek, Milan

    2016-09-01

    Electrical characteristics and ozone production measurements were performed to evaluate the efficiency of ozone generation using an amplitude-modulated AC Surface Dielectric Barrier Discharge (SDBD) in dry synthetic air and pure oxygen at atmospheric pressure. To increase the concentration and production of ozone we used the multiple SDBD electrode system consisting of several identical elements in parallel configuration. Each SDBD element is made of a thin alumina plate (10cm x 10 cm x 0,065cm) with metallic strips deposited on the upper side as a HV electrode and full square or strips on the opposite side as a ground electrode. An influence of a photocatalyst on ozone production was studied as well by inserting thin alumina plates coated with titanium dioxide thin films between SDBD electrodes. Alternatively, the SDBD electrodes directly coated with titanium dioxide were tested either. Dependence of ozone production on the discharge duty cycle and gas flow rate of 0,8 slm - 10 slm were evaluated. Work supported by TACR (Contract No. TA03010098).

  2. Generation of induced pluripotent stem cells with high efficiency from human umbilical cord blood mononuclear cells.

    Science.gov (United States)

    Wang, Juan; Gu, Qi; Hao, Jie; Bai, Donghui; Liu, Lei; Zhao, Xiaoyang; Liu, Zhonghua; Wang, Liu; Zhou, Qi

    2013-10-01

    Human induced pluripotent stem cells (iPSCs) hold great promise for regenerative medicine. Generating iPSCs from immunologically immature newborn umbilical cord blood mononuclear cells (UCBMCs) is of great significance. Here we report generation of human iPSCs with great efficiency from UCBMCs using a dox-inducible lentiviral system carrying four Yamanaka factors. We generated these cells by optimizing the existing iPSC induction protocol. The UCBMC-derived iPSCs (UCB-iPSCs) have characteristics that are identical to pluripotent human embryonic stem cells (hESCs). This study highlights the use of UCBMCs to generate highly functional human iPSCs that could accelerate the development of cell-based regenerative therapy for patients suffering from various diseases.

  3. Generation and In Vitro Expansion of Hepatic Progenitor Cells from Human iPS Cells.

    Science.gov (United States)

    Yanagida, Ayaka; Nakauchi, Hiromitsu; Kamiya, Akihide

    2016-01-01

    Stem cells have the unique properties of self-renewal and multipotency (producing progeny belonging to two or more lineages). Induced pluripotent stem (iPS) cells can be generated from somatic cells by simultaneous expression of pluripotent factors (Oct3/4, Klf4, Sox2, and c-Myc). They share the same properties as embryonic stem (ES) cells and can differentiate into several tissue cells, i.e., neurons, hematopoietic cells, and liver cells. Therefore, iPS cells are suitable candidate cells for regenerative medicine and analyses of disease mechanisms.The liver is the major organ that regulates a multitude of metabolic functions. Hepatocytes are the major cell type populating the liver parenchyma and express several metabolic enzymes that are necessary for liver functions. Although hepatocytes are essential for maintaining homeostasis, it is difficult to alter artificial and transplanted cells because of their multifunctionality, donor shortage, and immunorejection risk. During liver development, hepatic progenitor cells in the fetal liver differentiate into both mature hepatocytes and cholangiocytes. As hepatic progenitor cells have bipotency and high proliferation ability, they could present a potential source for generating transplantable cells or as a liver study model. Here we describe the induction and purification of hepatic progenitor cells derived from human iPS cells. These cells can proliferate for a long term under suitable culture conditions.

  4. Generation of chimeras by aggregation of embryonic stem cells with diploid or tetraploid mouse embryos.

    Science.gov (United States)

    Artus, Jérôme; Hadjantonakis, Anna-Katerina

    2011-01-01

    From the hybrid creatures of the Greek and Egyptian mythologies, the concept of the chimera has evolved and, in modern day biology, refers to an organism comprises of at least two populations of genetically distinct cells. Mouse chimeras have proven an invaluable tool for the generation of genetically modified strains. In addition, chimeras have been extensively used in developmental biology as a powerful tool to analyze the phenotype of specific mutations, to attribute function to gene products and to address the question of cell autonomy versus noncell autonomy of gene function. This chapter describes a simple and economical technique used to generate mouse chimeras by embryo aggregation. Multiple aggregation combinations are described each of which can be tailored to answer particular biological questions.

  5. Everolimus for Compassionate Use in Multiple Basal Cell Carcinomas

    Directory of Open Access Journals (Sweden)

    Laura Eibenschutz

    2013-01-01

    Full Text Available Everolimus is an inhibitor of the mammalian target of rapamycin (mTOR and has been shown to have antineoplastic activity in addition to its use as an immunosuppressive agent for the prevention of organ transplant rejection. We report the use of everolimus for the compassionate treatment of four elderly, nontransplant patients presenting with multiple basal cell carcinomas (BCC. All patients had a long history of BCC, had refused surgery as a current treatment option, and did not respond to alternative treatments (including topical 5-fluorouracil and imiquimod. Patients were treated with oral everolimus (1.5–3.0 mg daily for 12 months or longer: a complete and sustained response was seen in one case, and partial responses were seen in two other cases. Everolimus was well tolerated in these elderly patients. These promising preliminary data suggest that further dose-finding, controlled clinical studies are warranted to evaluate the antineoplastic effects of everolimus in patients affected by BCC who cannot or will not undergo surgery.

  6. High-order harmonics generated from single and multiple molecular orbits in mid-infrared laser fields

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    ZHANG Jingtao

    2015-08-01

    Full Text Available High-order harmonics generated from aligned molecules are studied by a nonperturbative QED theory and the effect of the multiple molecular orbits is included.The harmonic spectra generated from single molecular orbit exhibit an interference minimum which is induced by the molecular structure.The location of the spectral minimum shifts with the laser intensity in long laser pulses,but is fixed in ultrashort laser pulses.This difference is owed to the quiver motion of the electron in the laser pulses.The maximal shift of the spectral minimum equals to the increment of the ponderomotive energy and depends linearly on the laser intensity.The interference between the harmonics generated from multiple molecular orbits has two principal effects:one is obscuring the deep minima in the overall harmonic spectrum,the other is manifesting the phase jump in the harmonics generated from single molecular orbit.

  7. Cutting edge: Multiple sclerosis-like lesions induced by effector CD8 T cells recognizing a sequestered antigen on oligodendrocytes.

    Science.gov (United States)

    Saxena, Amit; Bauer, Jan; Scheikl, Tanja; Zappulla, Jacques; Audebert, Marc; Desbois, Sabine; Waisman, Ari; Lassmann, Hans; Liblau, Roland S; Mars, Lennart T

    2008-08-01

    CD8 T cells are emerging as important players in multiple sclerosis (MS) pathogenesis, although their direct contribution to tissue damage is still debated. To assess whether autoreactive CD8 T cells can contribute to the pronounced loss of oligodendrocytes observed in MS plaques, we generated mice in which the model Ag influenza hemagglutinin is selectively expressed in oligodendrocytes. Transfer of preactivated hemagglutinin-specific CD8 T cells led to inflammatory lesions in the optic nerve, spinal cord, and brain. These lesions, associating CD8 T cell infiltration with focal loss of oligodendrocytes, demyelination, and microglia activation, were very reminiscent of active MS lesions. Thus, our study demonstrates the potential of CD8 T cells to induce oligodendrocyte lysis in vivo as a likely consequence of direct Ag-recognition. These results provide new insights with regard to CNS tissue damage mediated by CD8 T cells and for understanding the role of CD8 T cells in MS.

  8. Generation of Transplantable Beta Cells for Patient-Specific Cell Therapy

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    Xiaojie Wang

    2012-01-01

    Full Text Available Islet cell transplantation offers a potential cure for type 1 diabetes, but it is challenged by insufficient donor tissue and side effects of current immunosuppressive drugs. Therefore, alternative sources of insulin-producing cells and isletfriendly immunosuppression are required to increase the efficiency and safety of this procedure. Beta cells can be transdifferentiated from precursors or another heterologous (non-beta-cell source. Recent advances in beta cell regeneration from somatic cells such as fibroblasts could circumvent the usage of immunosuppressive drugs. Therefore, generation of patient-specific beta cells provides the potential of an evolutionary treatment for patients with diabetes.

  9. Multi-gene gateway clone design for expression of multiple heterologous genes in living cells: modular construction of multiple cDNA expression elements using recombinant cloning.

    Science.gov (United States)

    Sone, Takefumi; Yahata, Kazuhide; Sasaki, Yukari; Hotta, Junko; Kishine, Hiroe; Chesnut, Jonathan D; Imamoto, Fumio

    2008-09-10

    Much attention has been focused on manipulating multiple genes in living cells for analyzing protein function. In order to perform high-throughput generation of multi-gene expression clones, gateway cloning technology (which represents a high-throughput DNA transfer from vector to vector) can be anticipated. In the conventional strategy for gateway cloning, the construction of two or more expression elements into tandem elements on a single plasmid requires the recombination of multiple entry clones with a destination vector in a single reaction mixture. Use of increasing numbers of entry clones in a single reaction is inefficient due to the difficulty in successfully recognizing multiple pairs of matched att signals simultaneously. To address this problem, a "Modular Destination" vector has been devised and constructed, whereby cDNA inserts are sequentially introduced, resulting in a tandem structure with multiple inserts. Whereas the standard destination vector contains only Cm(R) and ccdB genes flanked by two attR signals, this destination vector contains, in addition, one or two cDNA expression elements. Here, we show the rapid construction of expression vectors containing three or four tandemly arrayed cDNA expression elements and their expression in mammalian cells.

  10. A Bio-Based Fuel Cell for Distributed Energy Generation

    Energy Technology Data Exchange (ETDEWEB)

    Anthony Terrinoni; Sean Gifford

    2008-06-30

    The technology we propose consists primarily of an improved design for increasing the energy density of a certain class of bio-fuel cell (BFC). The BFCs we consider are those which harvest electrons produced by microorganisms during their metabolism of organic substrates (e.g. glucose, acetate). We estimate that our technology will significantly enhance power production (per unit volume) of these BFCs, to the point where they could be employed as stand-alone systems for distributed energy generation.

  11. Generation of Neurospheres from Human Adipose-Derived Stem Cells

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    Erfang Yang

    2015-01-01

    Full Text Available Transplantation of neural stem cells (NSCs to treat neurodegenerative disease shows promise; however, the clinical application of NSCs is limited by the invasive procurement and ethical concerns. Adipose-derived stem cells (ADSCs are a source of multipotent stem cells that can self-renew and differentiate into various kinds of cells; this study intends to generate neurospheres from human ADSCs by culturing ADSCs on uncoated culture flasks in serum-free neurobasal medium supplemented with B27, basic fibroblast growth factor (bFGF, and epidermal growth factor (EGF; the ADSCs-derived neurospheres were terminally differentiated after growth factor withdrawal. Expression of Nestin, NeuN, MAP2, and GFAP in ADSCs and terminally differentiated neurospheres was shown by quantitative reverse transcription-polymerase chain reaction (qRT-PCR, western blotting, and immunocytochemistry; cell proliferation in neurospheres was evaluated by cell cycle analyses, immunostaining, and flow cytometry. These data strongly support the conclusion that human ADSCs can successfully differentiate into neurospheres efficiently on uncoated culture flasks, which present similar molecular marker pattern and proliferative ability with NSCs derived from embryonic and adult brain tissues. Therefore, human ADSCs may be an ideal alternative source of stem cells for the treatment of neurodegenerative diseases.

  12. Generation of functional platelets from canine induced pluripotent stem cells.

    Science.gov (United States)

    Nishimura, Toshiya; Hatoya, Shingo; Kanegi, Ryoji; Sugiura, Kikuya; Wijewardana, Viskam; Kuwamura, Mitsuru; Tanaka, Miyuu; Yamate, Jyoji; Izawa, Takeshi; Takahashi, Masahiro; Kawate, Noritoshi; Tamada, Hiromichi; Imai, Hiroshi; Inaba, Toshio

    2013-07-15

    Thrombocytopenia (TTP) is a blood disease common to canines and human beings. Currently, there is no valid therapy for this disease except blood transfusion. In this study, we report the generation of canine induced pluripotent stem cells (ciPSCs) from canine embryonic fibroblasts, and a novel protocol for creating mature megakaryocytes (MKs) and functional platelets from ciPSCs. The ciPSCs were generated using lentiviral vectors, and differentiated into MKs and platelets on OP9 stromal cells supplemented with growth factors. Our ciPSCs presented in a tightly domed shape and showed expression of a critical pluripotency marker, REX1, and normal karyotype. Additionally, ciPSCs differentiated into cells derived from three germ layers via the formation of an embryoid body. The MKs derived from ciPSCs had hyperploidy and transformed into proplatelets. The proplatelets released platelets early on that expressed specific MK and platelet marker CD41/61. Interestingly, these platelets, when activated with adenosine diphosphate or thrombin, bind to fibrinogen. Moreover, electron microscopy showed that the platelets had the same ultrastructure as peripheral platelets. Thus, we have demonstrated for the first time the generation of ciPSCs that are capable of differentiating into MKs and release functional platelets in vitro. Our system for differentiating ciPSCs into MKs and platelets promises a critical therapy for canine TTP and appears to be extensible in principle to resolve human TTP.

  13. A method for multiple sequential analyses of macrophage functions using a small single cell sample

    Directory of Open Access Journals (Sweden)

    F.R.F. Nascimento

    2003-09-01

    Full Text Available Microbial pathogens such as bacillus Calmette-Guérin (BCG induce the activation of macrophages. Activated macrophages can be characterized by the increased production of reactive oxygen and nitrogen metabolites, generated via NADPH oxidase and inducible nitric oxide synthase, respectively, and by the increased expression of major histocompatibility complex class II molecules (MHC II. Multiple microassays have been developed to measure these parameters. Usually each assay requires 2-5 x 10(5 cells per well. In some experimental conditions the number of cells is the limiting factor for the phenotypic characterization of macrophages. Here we describe a method whereby this limitation can be circumvented. Using a single 96-well microassay and a very small number of peritoneal cells obtained from C3H/HePas mice, containing as little as <=2 x 10(5 macrophages per well, we determined sequentially the oxidative burst (H2O2, nitric oxide production and MHC II (IAk expression of BCG-activated macrophages. More specifically, with 100 µl of cell suspension it was possible to quantify H2O2 release and nitric oxide production after 1 and 48 h, respectively, and IAk expression after 48 h of cell culture. In addition, this microassay is easy to perform, highly reproducible and more economical.

  14. Antitumoral Effect of Hibiscus sabdariffa on Human Squamous Cell Carcinoma and Multiple Myeloma Cells.

    Science.gov (United States)

    Malacrida, Alessio; Maggioni, Daniele; Cassetti, Arianna; Nicolini, Gabriella; Cavaletti, Guido; Miloso, Mariarosaria

    2016-10-01

    Cancer is a leading cause of death worldwide. Despite therapeutic improvements, some cancers are still untreatable. Recently there has been an increasing interest in the use of natural substances for cancer prevention and treatment. Hibiscus sabdariffa (HS) is a plant, belonging to Malvaceae family, widespread in South Asia and Central Africa. HS extract (HSE) used in folk medicine, gained researchers' interest thanks to its antioxidant, anti-inflammatory, and chemopreventive properties. In the present study, we initially assessed HSE effect on a panel of human tumor cell lines. Then we focused our study on the following that are most sensitive to HSE action cell lines: Multiple Myeloma (MM) cells (RPMI 8226) and Oral Squamous Cell Carcinoma (OSCC) cells (SCC-25). In both RPMI 8226 and SCC-25 cells, HSE impaired cell growth, exerted a reversible cytostatic effect, and reduced cell motility and invasiveness. We evaluated the involvement of MAPKs ERK1/2 and p38 in HSE effects by using specific inhibitors, U0126 and SB203580, respectively. For both SCC-25 and RPMI 8226, HSE cytostatic effect depends on p38 activation, whereas ERK1/2 modulation is crucial for cell motility and invasiveness. Our results suggest that HSE may be a potential therapeutic agent against MM and OSCC.

  15. Single cell analysis of yeast replicative aging using a new generation of microfluidic device.

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    Yi Zhang

    Full Text Available A major limitation to yeast aging study has been the inability to track mother cells and observe molecular markers during the aging process. The traditional lifespan assay relies on manual micro-manipulation to remove daughter cells from the mother, which is laborious, time consuming, and does not allow long term tracking with high resolution microscopy. Recently, we have developed a microfluidic system capable of retaining mother cells in the microfluidic chambers while removing daughter cells automatically, making it possible to observe fluorescent reporters in single cells throughout their lifespan. Here we report the development of a new generation of microfluidic device that overcomes several limitations of the previous system, making it easier to fabricate and operate, and allowing functions not possible with the previous design. The basic unit of the device consists of microfluidic channels with pensile columns that can physically trap the mother cells while allowing the removal of daughter cells automatically by the flow of the fresh media. The whole microfluidic device contains multiple independent units operating in parallel, allowing simultaneous analysis of multiple strains. Using this system, we have reproduced the lifespan curves for the known long and short-lived mutants, demonstrating the power of the device for automated lifespan measurement. Following fluorescent reporters in single mother cells throughout their lifespan, we discovered a surprising change of expression of the translation elongation factor TEF2 during aging, suggesting altered translational control in aged mother cells. Utilizing the capability of the new device to trap mother-daughter pairs, we analyzed mother-daughter inheritance and found age dependent asymmetric partitioning of a general stress response reporter between mother and daughter cells.

  16. Generation of Human Induced Pluripotent Stem Cells from Peripheral Blood Mononuclear Cells Using Sendai Virus.

    Science.gov (United States)

    Soares, Filipa A C; Pedersen, Roger A; Vallier, Ludovic

    2016-01-01

    This protocol describes the efficient isolation of peripheral blood mononuclear cells from circulating blood via density gradient centrifugation and subsequent generation of integration-free human induced pluripotent stem cells. Peripheral blood mononuclear cells are cultured for 9 days to allow expansion of the erythroblast population. The erythroblasts are then used to derive human induced pluripotent stem cells using Sendai viral vectors, each expressing one of the four reprogramming factors Oct4, Sox2, Klf4, and c-Myc.

  17. In vivo generation of transplantable human hematopoietic cells from induced pluripotent stem cells.

    Science.gov (United States)

    Amabile, Giovanni; Welner, Robert S; Nombela-Arrieta, Cesar; D'Alise, Anna Morena; Di Ruscio, Annalisa; Ebralidze, Alexander K; Kraytsberg, Yevgenya; Ye, Min; Kocher, Olivier; Neuberg, Donna S; Khrapko, Konstantin; Silberstein, Leslie E; Tenen, Daniel G

    2013-02-21

    Lineage-restricted cells can be reprogrammed to a pluripotent state known as induced pluripotent stem (iPS) cells through overexpression of 4 transcription factors. iPS cells are similar to human embryonic stem (hES) cells and have the same ability to generate all the cells of the human body, including blood cells. However, this process is extremely inefficient and to date has been unsuccessful at differentiating iPS into hematopoietic stem cells (HSCs). We hypothesized that iPS cells, injected into NOD.Cg-Prkdc(scid) Il2rg(tm1Wjl)/SzJ immunocompromised (NSG) mice could give rise to hematopoietic stem/progenitor cells (HSPCs) during teratoma formation. Here, we report a novel in vivo system in which human iPS cells differentiate within teratomas to derive functional myeloid and lymphoid cells. Similarly, HSPCs can be isolated from teratoma parenchyma and reconstitute a human immune system when transplanted into immunodeficient mice. Our data provide evidence that in vivo generation of patient customized cells is feasible, providing materials that could be useful for transplantation, human antibody generation, and drug screening applications.

  18. Apoptosis of multiple myeloid cells induced by polysaccharides extracts from Hedyotis diffusa and its mechanism

    Institute of Scientific and Technical Information of China (English)

    林圣云

    2013-01-01

    Objective To explore the proliferation inhibition and apoptosis effects of polysaccharides extracts from Hedyotis diffusa(PEHD)on multiple myeloma(MM) cell line RPMI 8226 cells in vitro,so as to provide experimental

  19. The essential role of t cells in multiple sclerosis: A reappraisal

    Directory of Open Access Journals (Sweden)

    Cris S Constantinescu

    2014-04-01

    Full Text Available Multiple sclerosis is an inflammatory demyelinating disease of the central nervous system in which destruction of myelin and nerve axons has been shown to be mediated by immune mechanisms. Although the focus of research has been traditionally on T cells as key mediators of the immunopathology, more recent efforts at understanding this complex disorder have been directed increasingly at other cellular and humoral elements of the immune response. This review is a reappraisal of the crucial role of T cells, in particular the CD4+ helper T-cell subset, in multiple sclerosis. Recent evidence is discussed underlining the predominant contribution of T-cell-associated genes to the genome-wide association study results of multiple sclerosis susceptibility, the loss of T-cell quiescence in the conversion from clinically isolated syndrome to clinically definite multiple sclerosis, and the fact that T cells represent the main target of effective immunomodulatory and immunosuppressive treatments in multiple sclerosis.

  20. Generation of functional thyroid from embryonic stem cells.

    Science.gov (United States)

    Antonica, Francesco; Kasprzyk, Dominika Figini; Opitz, Robert; Iacovino, Michelina; Liao, Xiao-Hui; Dumitrescu, Alexandra Mihaela; Refetoff, Samuel; Peremans, Kathelijne; Manto, Mario; Kyba, Michael; Costagliola, Sabine

    2012-11-01

    The primary function of the thyroid gland is to metabolize iodide by synthesizing thyroid hormones, which are critical regulators of growth, development and metabolism in almost all tissues. So far, research on thyroid morphogenesis has been missing an efficient stem-cell model system that allows for the in vitro recapitulation of the molecular and morphogenic events regulating thyroid follicular-cell differentiation and subsequent assembly into functional thyroid follicles. Here we report that a transient overexpression of the transcription factors NKX2-1 and PAX8 is sufficient to direct mouse embryonic stem-cell differentiation into thyroid follicular cells that organize into three-dimensional follicular structures when treated with thyrotropin. These in vitro-derived follicles showed appreciable iodide organification activity. Importantly, when grafted in vivo into athyroid mice, these follicles rescued thyroid hormone plasma levels and promoted subsequent symptomatic recovery. Thus, mouse embryonic stem cells can be induced to differentiate into thyroid follicular cells in vitro and generate functional thyroid tissue.

  1. Generating trunk neural crest from human pluripotent stem cells.

    Science.gov (United States)

    Huang, Miller; Miller, Matthew L; McHenry, Lauren K; Zheng, Tina; Zhen, Qiqi; Ilkhanizadeh, Shirin; Conklin, Bruce R; Bronner, Marianne E; Weiss, William A

    2016-01-27

    Neural crest cells (NCC) are stem cells that generate different lineages, including neuroendocrine, melanocytic, cartilage, and bone. The differentiation potential of NCC varies according to the level from which cells emerge along the neural tube. For example, only anterior "cranial" NCC form craniofacial bone, whereas solely posterior "trunk" NCC contribute to sympathoadrenal cells. Importantly, the isolation of human fetal NCC carries ethical and scientific challenges, as NCC induction typically occur before pregnancy is detectable. As a result, current knowledge of NCC biology derives primarily from non-human organisms. Important differences between human and non-human NCC, such as expression of HNK1 in human but not mouse NCC, suggest a need to study human NCC directly. Here, we demonstrate that current protocols to differentiate human pluripotent stem cells (PSC) to NCC are biased toward cranial NCC. Addition of retinoic acid drove trunk-related markers and HOX genes characteristic of a posterior identity. Subsequent treatment with bone morphogenetic proteins (BMPs) enhanced differentiation to sympathoadrenal cells. Our approach provides methodology for detailed studies of human NCC, and clarifies roles for retinoids and BMPs in the differentiation of human PSC to trunk NCC and to sympathoadrenal lineages.

  2. Generation of functional podocytes from human induced pluripotent stem cells

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    Osele Ciampi

    2016-07-01

    Full Text Available Generating human podocytes in vitro could offer a unique opportunity to study human diseases. Here, we describe a simple and efficient protocol for obtaining functional podocytes in vitro from human induced pluripotent stem cells. Cells were exposed to a three-step protocol, which induced their differentiation into intermediate mesoderm, then into nephron progenitors and, finally, into mature podocytes. After differentiation, cells expressed the main podocyte markers, such as synaptopodin, WT1, α-Actinin-4, P-cadherin and nephrin at the protein and mRNA level, and showed the low proliferation rate typical of mature podocytes. Exposure to Angiotensin II significantly decreased the expression of podocyte genes and cells underwent cytoskeleton rearrangement. Cells were able to internalize albumin and self-assembled into chimeric 3D structures in combination with dissociated embryonic mouse kidney cells. Overall, these findings demonstrate the establishment of a robust protocol that, mimicking developmental stages, makes it possible to derive functional podocytes in vitro.

  3. Generation of induced pluripotent stem cells from domestic goats.

    Science.gov (United States)

    Sandmaier, Shelley E S; Nandal, Anjali; Powell, Anne; Garrett, Wesley; Blomberg, Leann; Donovan, David M; Talbot, Neil; Telugu, Bhanu P

    2015-09-01

    The creation of genetically modified goats provides a powerful approach for improving animal health, enhancing production traits, animal pharming, and for ensuring food safety all of which are high-priority goals for animal agriculture. The availability of goat embryonic stem cells (ESCs) that are characteristically immortal in culture would be of enormous benefit for developing genetically modified animals. As an alternative to long-sought goat ESCs, we generated induced pluripotent stem cells (iPSC) by forced expression of bovine POU5F1, SOX2, MYC, KLF4, LIN-28, and NANOG reprogramming factors in combination with a MIR302/367 cluster, delivered by lentiviral vectors. In order to minimize integrations, the reprogramming factor coding sequences were assembled with porcine teschovirus-1 2A (P2A) self-cleaving peptides that allowed for tri-cistronic expression from each vector. The lentiviral-transduced cells were cultured on irradiated mouse feeder cells in a semi-defined, serum-free medium containing fibroblast growth factor (FGF) and/or leukemia inhibitory factor (LIF). The resulting goat iPSC exhibit cell and colony morphology typical of human and mouse ESCs-that is, well-defined borders, a high nuclear-to-cytoplasmic ratio, a short cell-cycle interval, alkaline phosphatase expression, and the ability to generate teratomas in vivo. Additionally, these goat iPSC demonstrated the ability to differentiate into directed lineages in vitro. These results constitute the first steps in establishing integration and footprint-free iPSC from ruminants. Mol. Reprod. Dev. 82: 709-721, 2015. © 2015 Wiley Periodicals, Inc.

  4. Invariant natural killer T cells and mucosal-associated invariant T cells in multiple sclerosis.

    Science.gov (United States)

    Bianchini, Elena; De Biasi, Sara; Simone, Anna Maria; Ferraro, Diana; Sola, Patrizia; Cossarizza, Andrea; Pinti, Marcello

    2017-03-01

    Multiple sclerosis (MS) is a chronic progressive inflammatory demyelinating disorder of the central nervous system, and in several countries is a leading cause of permanent neurological disability in young adults, particularly women. MS is considered an autoimmune disease, caused by an aberrant immune response to environmental triggers in genetically susceptible subjects. However, the contribution of the innate or of the adaptive immune system to the development and progression of the disease has not yet been fully elucidated. Innate-like T lymphocytes are unconventional T cells that bridge the innate and adaptive arms of the immune system, because they use a T cell receptor to sense external ligands, but behave like innate cells when they rapidly respond to stimuli. These cells could play an important role in the pathogenesis of MS. Here, we focus on invariant natural killer T (iNKT) cells and mucosal-associated invariant T (MAIT) cells, and we review the current knowledge on their biology and possible involvement in MS. Although several studies have evaluated the frequency and functions of iNKT and MAIT cells both in MS patients and in experimental mouse models, contradictory observations have been reported, and it is not clear whether they exert a protective or a pro-inflammatory and harmful role. A better understanding of how immune cells are involved in MS, and of their interactions could be of great interest for the development of new therapeutic strategies.

  5. Establishment of Multiple Myeloma Cell lines with Hepatocyte growth factor (HGF) overexpression and knockdown

    OpenAIRE

    Qadir, Fouzia

    2013-01-01

    Multiple myeloma is the malignancy of plasma cells which causes 0.9 % of all cancer related deaths. These malignant plasma cells acquire chromosomal abnormalities and complex genetic instability. Hepatocyte growth factor (HGF) is a multifunctional cytokine promoting cell proliferation, survival, motility, scattering, differentiation and morphogenesis. HGF/c-MET pathway plays an important role in multiple myeloma pathogenesis and in extravasation and homing of myeloma cells to bone marrow micr...

  6. Adhesion-Dependent Wave Generation in Crawling Cells.

    Science.gov (United States)

    Barnhart, Erin L; Allard, Jun; Lou, Sunny S; Theriot, Julie A; Mogilner, Alex

    2017-01-09

    Dynamic actin networks are excitable. In migrating cells, feedback loops can amplify stochastic fluctuations in actin dynamics, often resulting in traveling waves of protrusion. The precise contributions of various molecular and mechanical interactions to wave generation have been difficult to disentangle, in part due to complex cellular morphodynamics. Here we used a relatively simple cell type-the fish epithelial keratocyte-to define a set of mechanochemical feedback loops underlying actin network excitability and wave generation. Although keratocytes are normally characterized by the persistent protrusion of a broad leading edge, increasing cell-substrate adhesion strength results in waving protrusion of a short leading edge. We show that protrusion waves are due to fluctuations in actin polymerization rates and that overexpression of VASP, an actin anti-capping protein that promotes actin polymerization, switches highly adherent keratocytes from waving to persistent protrusion. Moreover, VASP localizes both to adhesion complexes and to the leading edge. Based on these results, we developed a mathematical model for protrusion waves in which local depletion of VASP from the leading edge by adhesions-along with lateral propagation of protrusion due to the branched architecture of the actin network and negative mechanical feedback from the cell membrane-results in regular protrusion waves. Consistent with our model simulations, we show that VASP localization at the leading edge oscillates, with VASP leading-edge enrichment greatest just prior to protrusion initiation. We propose that the mechanochemical feedbacks underlying wave generation in keratocytes may constitute a general module for establishing excitable actin dynamics in other cellular contexts.

  7. Generation of retinal pigment epithelial cells from human embryonic stem cell-derived spherical neural masses.

    Science.gov (United States)

    Cho, Myung Soo; Kim, Sang Jin; Ku, Seung-Yup; Park, Jung Hyun; Lee, Haksup; Yoo, Dae Hoon; Park, Un Chul; Song, Seul Ae; Choi, Young Min; Yu, Hyeong Gon

    2012-09-01

    Dysfunction and loss of retinal pigment epithelium (RPE) are major pathologic changes observed in various retinal degenerative diseases such as aged-related macular degeneration. RPE generated from human pluripotent stem cells can be a good candidate for RPE replacement therapy. Here, we show the differentiation of human embryonic stem cells (hESCs) toward RPE with the generation of spherical neural masses (SNMs), which are pure masses of hESCs-derived neural precursors. During the early passaging of SNMs, cystic structures arising from opened neural tube-like structures showed pigmented epithelial morphology. These pigmented cells were differentiated into functional RPE by neuroectodermal induction and mechanical purification. Most of the differentiated cells showed typical RPE morphologies, such as a polygonal-shaped epithelial monolayer, and transmission electron microscopy revealed apical microvilli, pigment granules, and tight junctions. These cells also expressed molecular markers of RPE, including Mitf, ZO-1, RPE65, CRALBP, and bestrophin. The generated RPE also showed phagocytosis of isolated bovine photoreceptor outer segment and secreting pigment epithelium-derived factor and vascular endothelial growth factor. Functional RPE could be generated from SNM in our method. Because SNMs have several advantages, including the capability of expansion for long periods without loss of differentiation capability, easy storage and thawing, and no need for feeder cells, our method for RPE differentiation may be used as an efficient strategy for generating functional RPE cells for retinal regeneration therapy.

  8. Multiple Exemplar Instruction and the Emergence of Generative Production of Suffixes as Autoclitic Frames

    Science.gov (United States)

    Speckman, JeanneMarie; Greer, R. Douglas; Rivera-Valdes, Celestina

    2012-01-01

    We report 2 experiments that tested the effects of multiple exemplar instruction (MEI) across training sets on the emergence of productive autoclitic frames (suffixes) for 6 preschoolers with and without language-based disabilities. We implemented multiple exemplar tact instruction with subsets of stimuli whose "names" contained the suffix "-er"…

  9. An Exhaustive Analysis of Multiplicative Congruential Random Number Generators with Modulus 2(31)-1.

    Science.gov (United States)

    1984-06-01

    these generators. Shortly thereafter Marsaglia (1968) showed that all such generators share I -2- a common theoretical flaw and Coveyou and MacPherson...1967), Beyer, Roof and Williamson (1971), Marsaglia (1972) and Smith (1971) proposed alternative procedures for rating the seriousness of this flaw for...generators of types 2 and 3 are commonly used. On IBM computers with a word size of 32 bits and C = 0, the generator called SUPER-DUPER 32( Marsaglia 1972

  10. Generation and characterization of functional cardiomyocytes derived from human T cell-derived induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Tomohisa Seki

    Full Text Available Induced pluripotent stem cells (iPSCs have been proposed as novel cell sources for genetic disease models and revolutionary clinical therapies. Accordingly, human iPSC-derived cardiomyocytes are potential cell sources for cardiomyocyte transplantation therapy. We previously developed a novel generation method for human peripheral T cell-derived iPSCs (TiPSCs that uses a minimally invasive approach to obtain patient cells. However, it remained unknown whether TiPSCs with genomic rearrangements in the T cell receptor (TCR gene could differentiate into functional cardiomyocyte in vitro. To address this issue, we investigated the morphology, gene expression pattern, and electrophysiological properties of TiPSC-derived cardiomyocytes differentiated by floating culture. RT-PCR analysis and immunohistochemistry showed that the TiPSC-derived cardiomyocytes properly express cardiomyocyte markers and ion channels, and show the typical cardiomyocyte morphology. Multiple electrode arrays with application of ion channel inhibitors also revealed normal electrophysiological responses in the TiPSC-derived cardiomyocytes in terms of beating rate and the field potential waveform. In this report, we showed that TiPSCs successfully differentiated into cardiomyocytes with morphology, gene expression patterns, and electrophysiological features typical of native cardiomyocytes. TiPSCs-derived cardiomyocytes obtained from patients by a minimally invasive technique could therefore become disease models for understanding the mechanisms of cardiac disease and cell sources for revolutionary cardiomyocyte therapies.

  11. Evaluating the Psychometric Characteristics of Generated Multiple-Choice Test Items

    Science.gov (United States)

    Gierl, Mark J.; Lai, Hollis; Pugh, Debra; Touchie, Claire; Boulais, André-Philippe; De Champlain, André

    2016-01-01

    Item development is a time- and resource-intensive process. Automatic item generation integrates cognitive modeling with computer technology to systematically generate test items. To date, however, items generated using cognitive modeling procedures have received limited use in operational testing situations. As a result, the psychometric…

  12. Melanin Transfer in Human 3D Skin Equivalents Generated Exclusively from Induced Pluripotent Stem Cells.

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    Karl Gledhill

    Full Text Available The current utility of 3D skin equivalents is limited by the fact that existing models fail to recapitulate the cellular complexity of human skin. They often contain few cell types and no appendages, in part because many cells found in the skin are difficult to isolate from intact tissue and cannot be expanded in culture. Induced pluripotent stem cells (iPSCs present an avenue by which we can overcome this issue due to their ability to be differentiated into multiple cell types in the body and their unlimited growth potential. We previously reported generation of the first human 3D skin equivalents from iPSC-derived fibroblasts and iPSC-derived keratinocytes, demonstrating that iPSCs can provide a foundation for modeling a complex human organ such as skin. Here, we have increased the complexity of this model by including additional iPSC-derived melanocytes. Epidermal melanocytes, which are largely responsible for skin pigmentation, represent the second most numerous cell type found in normal human epidermis and as such represent a logical next addition. We report efficient melanin production from iPSC-derived melanocytes and transfer within an entirely iPSC-derived epidermal-melanin unit and generation of the first functional human 3D skin equivalents made from iPSC-derived fibroblasts, keratinocytes and melanocytes.

  13. Non-Viral Generation of Neural Precursor-like Cells from Adult Human Fibroblasts

    Directory of Open Access Journals (Sweden)

    Maucksch C

    2012-01-01

    Full Text Available Recent studies have reported direct reprogramming of human fibroblasts to mature neurons by the introduction of defined neural genes. This technology has potential use in the areas of neurological disease modeling and drug development. However, use of induced neurons for large-scale drug screening and cell-based replacement strategies is limited due to their inability to expand once reprogrammed. We propose it would be more desirable to induce expandable neural precursor cells directly from human fibroblasts. To date several pluripotent and neural transcription factors have been shown to be capable of converting mouse fibroblasts to neural stem/precursor-like cells when delivered by viral vectors. Here we extend these findings and demonstrate that transient ectopic insertion of the transcription factors SOX2 and PAX6 to adult human fibroblasts through use of non-viral plasmid transfection or protein transduction allows the generation of induced neural precursor (iNP colonies expressing a range of neural stem and pro-neural genes. Upon differentiation, iNP cells give rise to neurons exhibiting typical neuronal morphologies and expressing multiple neuronal markers including tyrosine hydroxylase and GAD65/67. Importantly, iNP-derived neurons demonstrate electrophysiological properties of functionally mature neurons with the capacity to generate action potentials. In addition, iNP cells are capable of differentiating into glial fibrillary acidic protein (GFAP-expressing astrocytes. This study represents a novel virus-free approach for direct reprogramming of human fibroblasts to a neural precursor fate.

  14. Efficient and cost-effective generation of mature neurons from human induced pluripotent stem cells.

    Science.gov (United States)

    Badja, Cherif; Maleeva, Galyna; El-Yazidi, Claire; Barruet, Emilie; Lasserre, Manon; Tropel, Philippe; Binetruy, Bernard; Bregestovski, Piotr; Magdinier, Frédérique

    2014-12-01

    For years, our ability to study pathological changes in neurological diseases has been hampered by the lack of relevant models until the recent groundbreaking work from Yamanaka's group showing that it is feasible to generate induced pluripotent stem cells (iPSCs) from human somatic cells and to redirect the fate of these iPSCs into differentiated cells. In particular, much interest has focused on the ability to differentiate human iPSCs into neuronal progenitors and functional neurons for relevance to a large number of pathologies including mental retardation and behavioral or degenerative syndromes. Current differentiation protocols are time-consuming and generate limited amounts of cells, hindering use on a large scale. We describe a feeder-free method relying on the use of a chemically defined medium that overcomes the need for embryoid body formation and neuronal rosette isolation for neuronal precursors and terminally differentiated neuron production. Four days after induction, expression of markers of the neurectoderm lineage is detectable. Between 4 and 7 days, neuronal precursors can be expanded, frozen, and thawed without loss of proliferation and differentiation capacities or further differentiated. Terminal differentiation into the different subtypes of mature neurons found in the human brain were observed. At 6-35 days after induction, cells express typical voltage-gated and ionotrophic receptors for GABA, glycine, and acetylcholine. This specific and efficient single-step strategy in a chemically defined medium allows the production of mature neurons in 20-40 days with multiple applications, especially for modeling human pathologies.

  15. Generation of Viable Cell and Biomaterial Patterns by Laser Transfer

    Science.gov (United States)

    Ringeisen, Bradley

    2001-03-01

    In order to fabricate and interface biological systems for next generation applications such as biosensors, protein recognition microarrays, and engineered tissues, it is imperative to have a method of accurately and rapidly depositing different active biomaterials in patterns or layered structures. Ideally, the biomaterial structures would also be compatible with many different substrates including technologically relevant platforms such as electronic circuits or various detection devices. We have developed a novel laser-based technique, termed matrix assisted pulsed laser evaporation direct write (MAPLE DW), that is able to direct write patterns and three-dimensional structures of numerous biologically active species ranging from proteins and antibodies to living cells. Specifically, we have shown that MAPLE DW is capable of forming mesoscopic patterns of living prokaryotic cells (E. coli bacteria), living mammalian cells (Chinese hamster ovaries), active proteins (biotinylated bovine serum albumin, horse radish peroxidase), and antibodies specific to a variety of classes of cancer related proteins including intracellular and extracellular matrix proteins, signaling proteins, cell cycle proteins, growth factors, and growth factor receptors. In addition, patterns of viable cells and active biomolecules were deposited on different substrates including metals, semiconductors, nutrient agar, and functionalized glass slides. We will present an explanation of the laser-based transfer mechanism as well as results from our recent efforts to fabricate protein recognition microarrays and tissue-based microfluidic networks.

  16. On generating cell exemplars for detection of mitotic cells in breast cancer histopathology images.

    Science.gov (United States)

    Aloraidi, Nada A; Sirinukunwattana, Korsuk; Khan, Adnan M; Rajpoot, Nasir M

    2014-01-01

    Mitotic activity is one of the main criteria that pathologists use to decide the grade of the cancer. Computerised mitotic cell detection promises to bring efficiency and accuracy into the grading process. However, detection and classification of mitotic cells in breast cancer histopathology images is a challenging task because of the large intra-class variation in the visual appearance of mitotic cells in various stages of cell division life cycle. In this paper, we test the hypothesis that cells in histopathology images can be effectively represented using cell exemplars derived from sub-images of various kinds of cells in an image for the purposes of mitotic cell classification. We compare three methods for generating exemplar cells. The methods have been evaluated in terms of classification performance on the MITOS dataset. The experimental results demonstrate that eigencells combined with support vector machines produce reasonably high detection accuracy among all the methods.

  17. Microbial fuel cells: novel biotechnology for energy generation.

    Science.gov (United States)

    Rabaey, Korneel; Verstraete, Willy

    2005-06-01

    Microbial fuel cells (MFCs) provide new opportunities for the sustainable production of energy from biodegradable, reduced compounds. MFCs function on different carbohydrates but also on complex substrates present in wastewaters. As yet there is limited information available about the energy metabolism and nature of the bacteria using the anode as electron acceptor; few electron transfer mechanisms have been established unequivocally. To optimize and develop energy production by MFCs fully this knowledge is essential. Depending on the operational parameters of the MFC, different metabolic pathways are used by the bacteria. This determines the selection and performance of specific organisms. Here we discuss how bacteria use an anode as an electron acceptor and to what extent they generate electrical output. The MFC technology is evaluated relative to current alternatives for energy generation.

  18. Role of prolactin in B cell regulation in multiple sclerosis.

    Science.gov (United States)

    Correale, Jorge; Farez, Mauricio F; Ysrraelit, María Célica

    2014-04-15

    The role of prolactin in MS pathogenesis was investigated. Prolactin levels were higher in MS subjects both during remission and exacerbation compared to control subjects. Prolactin increased JAK2 expression and Stat phosphorylation on B cells, up-regulated anti-MOG antibody secreting cell numbers, BAFF levels, and Bcl-2expression, and down-regulated expression of Trp63. Prolactin levels correlated positively with anti-MOG secreting cell numbers, and negatively with induced apoptotic B cells. Additionally, prolactin decreased B cell receptor-mediated activation threshold, and induced CD40 expression in B cells. These findings suggest that prolactin promotes B cell autoreactivity in MS through different mechanisms.

  19. a Pseudo-Random Number Generator Employing Multiple RÉNYI Maps

    Science.gov (United States)

    Lui, Oi-Yan; Yuen, Ching-Hung; Wong, Kwok-Wo

    2013-11-01

    The increasing risk along with the drastic development of multimedia data transmission has raised a big concern on data security. A good pseudo-random number generator is an essential tool in cryptography. In this paper, we propose a novel pseudo-random number generator based on the controlled combination of the outputs of several digitized chaotic Rényi maps. The generated pseudo-random sequences have passed both the NIST 800-22 Revision 1a and the DIEHARD tests. Moreover, simulation results show that the proposed pseudo-random number generator requires less operation time than existing generators and is highly sensitive to the seed.

  20. Glycogen Synthase Kinase-3 regulates multiple myeloma cell growth and bortezomib-induced cell death

    Directory of Open Access Journals (Sweden)

    Colpo Anna

    2010-10-01

    Full Text Available Abstract Background Glycogen Synthase Kinase-3 (GSK-3 α and β are two serine-threonine kinases controlling insulin, Wnt/β-catenin, NF-κB signaling and other cancer-associated transduction pathways. Recent evidence suggests that GSK-3 could function as growth-promoting kinases, especially in malignant cells. In this study, we have investigated GSK-3α and GSK-3β function in multiple myeloma (MM. Methods GSK-3 α and β expression and cellular localization were investigated by Western blot (WB and immunofluorescence analysis in a panel of MM cell lines and in freshly isolated plasma cells from patients. MM cell growth, viability and sensitivity to bortezomib was assessed upon treatment with GSK-3 specific inhibitors or transfection with siRNAs against GSK-3 α and β isoforms. Survival signaling pathways were studied with WB analysis. Results GSK-3α and GSK-3β were differently expressed and phosphorylated in MM cells. Inhibition of GSK-3 with the ATP-competitive, small chemical compounds SB216763 and SB415286 caused MM cell growth arrest and apoptosis through the activation of the intrinsic pathway. Importantly, the two inhibitors augmented the bortezomib-induced MM cell cytotoxicity. RNA interference experiments showed that the two GSK-3 isoforms have distinct roles: GSK-3β knock down decreased MM cell viability, while GSK-3α knock down was associated with a higher rate of bortezomib-induced cytotoxicity. GSK-3 inhibition caused accumulation of β-catenin and nuclear phospho-ERK1, 2. Moreover, GSK-3 inhibition and GSK-3α knockdown enhanced bortezomib-induced AKT and MCL-1 protein degradation. Interestingly, bortezomib caused a reduction of GSK-3 serine phosphorylation and its nuclear accumulation with a mechanism that resulted partly dependent on GSK-3 itself. Conclusions These data suggest that in MM cells GSK-3α and β i play distinct roles in cell survival and ii modulate the sensitivity to proteasome inhibitors.

  1. Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells.

    Science.gov (United States)

    Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

    2016-08-01

    Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.

  2. Generation of functional hepatocyte-like cells from human deciduous periodontal ligament stem cells

    Science.gov (United States)

    Vasanthan, Punitha; Jayaraman, Pukana; Kunasekaran, Wijenthiran; Lawrence, Anthony; Gnanasegaran, Nareshwaran; Govindasamy, Vijayendran; Musa, Sabri; Kasim, Noor Hayaty Abu

    2016-08-01

    Human deciduous periodontal ligament stem cells have been introduced for as an easily accessible source of stem cells from dental origin. Although recent studies have revealed the ability of these stem cells in multipotential attribute, their efficiency of hepatic lineage differentiation has not been addressed so far. The aim of this study is to investigate hepatic lineage fate competence of periodontal ligament stem cells through direct media induction. Differentiation of periodontal ligament stem cells into hepatocyte-like cells was conducted by the exposure of two phase media induction. First phase was performed in the presence of hepatocyte growth factors to induce a definitive endoderm formation. In the subsequent phase, the cells were treated with oncostatin M and dexamethosone followed by insulin and transferrin to generate hepatocyte-like cells. Hepatic-related characters of the generated hepatocyte-like cells were determined at both mRNA and protein level followed by functional assays. Foremost changes observed in the generation of hepatocyte-like cells were the morphological features in which these cells were transformed from fibroblastic shape to polygonal shape. Temporal expression of hepatic markers ranging from early endodermal up to late markers were detected in the hepatocyte-like cells. Crucial hepatic markers such as glycogen storage, albumin, and urea secretion were also shown. These findings exhibited the ability of periodontal ligament stem cells of dental origin to be directed into hepatic lineage fate. These cells can be regarded as an alternative autologous source in the usage of stem cell-based treatment for liver diseases.

  3. Statistical inference of the generation probability of T-cell receptors from sequence repertoires.

    Science.gov (United States)

    Murugan, Anand; Mora, Thierry; Walczak, Aleksandra M; Callan, Curtis G

    2012-10-02

    Stochastic rearrangement of germline V-, D-, and J-genes to create variable coding sequence for certain cell surface receptors is at the origin of immune system diversity. This process, known as "VDJ recombination", is implemented via a series of stochastic molecular events involving gene choices and random nucleotide insertions between, and deletions from, genes. We use large sequence repertoires of the variable CDR3 region of human CD4+ T-cell receptor beta chains to infer the statistical properties of these basic biochemical events. Because any given CDR3 sequence can be produced in multiple ways, the probability distribution of hidden recombination events cannot be inferred directly from the observed sequences; we therefore develop a maximum likelihood inference method to achieve this end. To separate the properties of the molecular rearrangement mechanism from the effects of selection, we focus on nonproductive CDR3 sequences in T-cell DNA. We infer the joint distribution of the various generative events that occur when a new T-cell receptor gene is created. We find a rich picture of correlation (and absence thereof), providing insight into the molecular mechanisms involved. The generative event statistics are consistent between individuals, suggesting a universal biochemical process. Our probabilistic model predicts the generation probability of any specific CDR3 sequence by the primitive recombination process, allowing us to quantify the potential diversity of the T-cell repertoire and to understand why some sequences are shared between individuals. We argue that the use of formal statistical inference methods, of the kind presented in this paper, will be essential for quantitative understanding of the generation and evolution of diversity in the adaptive immune system.

  4. Clinical grade of generation of dendritic cells for immunotherapy.

    Science.gov (United States)

    Tang, Duozhuang; Tao, Si; Cao, Yang; Zhou, Jianfeng; Ma, Ding; Huang, Wei

    2007-06-01

    In order to develop a protocol for clinical grade generation of dendritic cells (DCs) for cancer immunotherapy, aphereses were performed with the continuous flow cell separator and materials were derived from 10 leukemia patients that had achieved complete remission. Peripheral blood monocytes were cultured in vitro with GM-CSF, IL-4 for 6 days, then TNF-(the TNF-group) or TNF-, IL-1, IL-6, PGE2 (the cytokine mixture group) were added to promote maturation. Cell number was counted by hematology analyzer, and phenotype study (CD1a, CD14, CD83) was carried out by flow cytometry, and the function of DCs was examined by mixed lymphocyte reaction. The results showed that (0.70+/-0.13)x10(7)/mL (the TNF-alpha group) and (0.79+/-0.04)x10(7)/mL (the cytokine mixture group) DCs were generated respectively in peripheral blood obtained by leucapheresis. The phenotypes were as follows: CD1a+ (74.65+/-4.45)%, CD83+ (39.50+/-4.16)%, CD14+ (2.90+/-1.76)% in TNF-alpha group, and CD1a+ (81.86+/-5.87)%, CD83+ (81.65+/-6.36)%, CD14+ (2.46+/-1.68)% in the cytokine mixture group. It was concluded that leucapheresis may be a feasible way to provide large number of peripheral blood monocytes for DC generation, and combined administration of TNF-, IL-1, IL-6, and PGE2 may greatly promote maturity.

  5. Novel nanostructures for next generation dye-sensitized solar cells

    KAUST Repository

    Tétreault, Nicolas

    2012-01-01

    Herein, we review our latest advancements in nanostructured photoanodes for next generation photovoltaics in general and dye-sensitized solar cells in particular. Bottom-up self-assembly techniques are developed to fabricate large-area 3D nanostructures that enable enhanced charge extraction and light harvesting through optical scattering or photonic crystal effects to improve photocurrent, photovoltage and fill factor. Using generalized techniques to fabricate specialized nanostructures enables specific optoelectronic and physical characteristics like conduction, charge extraction, injection, recombination and light harvesting but also helps improve mechanical flexibility and long-term stability in low cost materials. © 2012 The Royal Society of Chemistry.

  6. Development of planar solid oxide fuel cells for power generation applications

    Energy Technology Data Exchange (ETDEWEB)

    Minh, N.Q. [AlliedSignal Aerospce Equipment Systems, Torrance, CA (United States)

    1996-04-01

    Planar solid oxide fuel cells (SOFCs) are presently being developed for a variety of electric power generation application. The planar design offers simple cell geometry, high power density, and multiple fabrication and gas manifolding options. Planar SOFC technology has received much attention recently, and significant progress has been made in this area. Recent effort at AlliedSignal has focused on the development of high-performance, lightweight planar SOFCs, having thin-electrolyte films, that can be operated efficiently at reduced temperatures (< 1000{degrees}C). The advantages of reduced-temperature operation include wider material choice (including use of metallic interconnects), expected longer cell life, reduced thermal stress, improved reliability, and reduced fuel cell cost. The key aspect in the development of thin-film SIFCs is to incorporate the thin electrolyte layer into the desired structure of cells in a manner that yields the required characteristics. AlliedSignal has developed a simple and cost-effective method based on tape calendering for the fabrication of thin-electrolyte SOFCs. Thin-electrolyte cells made by tape calendering have shown extraordinary performance, e.g., producing more than 500mW/cm{sup 2} at 700{degrees}C and 800mW/cm{sup 2} at 800{degrees}C with hydrogen as fuel and air is oxidant. thin-electrolyte single cells have been incorporated into a compliant metallic stack structure and operated at reduced and operated at reduced-temperature conditions.

  7. Releasing dentate nucleus cells from Purkinje cell inhibition generates output from the cerebrocerebellum.

    Directory of Open Access Journals (Sweden)

    Takahiro Ishikawa

    Full Text Available The cerebellum generates its vast amount of output to the cerebral cortex through the dentate nucleus (DN that is essential for precise limb movements in primates. Nuclear cells in DN generate burst activity prior to limb movement, and inactivation of DN results in cerebellar ataxia. The question is how DN cells become active under intensive inhibitory drive from Purkinje cells (PCs. There are two excitatory inputs to DN, mossy fiber and climbing fiber collaterals, but neither of them appears to have sufficient strength for generation of burst activity in DN. Therefore, we can assume two possible mechanisms: post-inhibitory rebound excitation and disinhibition. If rebound excitation works, phasic excitation of PCs and a concomitant inhibition of DN cells should precede the excitation of DN cells. On the other hand, if disinhibition plays a primary role, phasic suppression of PCs and activation of DN cells should be observed at the same timing. To examine these two hypotheses, we compared the activity patterns of PCs in the cerebrocerebellum and DN cells during step-tracking wrist movements in three Japanese monkeys. As a result, we found that the majority of wrist-movement-related PCs were suppressed prior to movement onset and the majority of wrist-movement-related DN cells showed concurrent burst activity without prior suppression. In a minority of PCs and DN cells, movement-related increases and decreases in activity, respectively, developed later. These activity patterns suggest that the initial burst activity in DN cells is generated by reduced inhibition from PCs, i.e., by disinhibition. Our results indicate that suppression of PCs, which has been considered secondary to facilitation, plays the primary role in generating outputs from DN. Our findings provide a new perspective on the mechanisms used by PCs to influence limb motor control and on the plastic changes that underlie motor learning in the cerebrocerebellum.

  8. Low-Power, Rad-hard Reconfigurable, Bi-directional Flexfet? Level Shifter ReBiLS for Multiple Generation Technology Integration for Space Exploration Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The many different generations of integrated circuit (IC) technologies required for new space exploration systems demand designs operate at multiple and often...

  9. Septins and Generation of Asymmetries in Fungal Cells

    Science.gov (United States)

    Khan, Anum; McQuilken, Molly

    2017-01-01

    Polarized growth is critical for the development and maintenance of diverse organisms and tissues, but particularly central to fungi where nutrient uptake, communication, and reproduction all rely on cell asymmetries. To achieve polarized growth, fungi spatially organize both their cytosol and cortical membranes. The septins, a family of GTP-binding proteins, have emerged as key regulators of spatial compartmentalization in fungi and other eukaryotes. By forming higher-order structures on fungal plasma membranes, septins are thought to contribute to the generation of cell asymmetries by acting as molecular scaffolds and forming diffusional barriers. Here we discuss the links between septins and polarized growth and consider molecular models for how septins contribute to cellular asymmetry in fungi. PMID:26488282

  10. Septins and Generation of Asymmetries in Fungal Cells.

    Science.gov (United States)

    Khan, Anum; McQuilken, Molly; Gladfelter, Amy S

    2015-01-01

    Polarized growth is critical for the development and maintenance of diverse organisms and tissues but particularly so in fungi, where nutrient uptake, communication, and reproduction all rely on cell asymmetries. To achieve polarized growth, fungi spatially organize both their cytosol and cortical membranes. Septins, a family of GTP-binding proteins, are key regulators of spatial compartmentalization in fungi and other eukaryotes. Septins form higher-order structures on fungal plasma membranes and are thought to contribute to the generation of cell asymmetries by acting as molecular scaffolds and forming diffusional barriers. Here we discuss the links between septins and polarized growth and consider molecular models for how septins contribute to cellular asymmetry in fungi.

  11. Somatic cell reprogramming-free generation of genetically modified pigs

    Science.gov (United States)

    Tanihara, Fuminori; Takemoto, Tatsuya; Kitagawa, Eri; Rao, Shengbin; Do, Lanh Thi Kim; Onishi, Akira; Yamashita, Yukiko; Kosugi, Chisato; Suzuki, Hitomi; Sembon, Shoichiro; Suzuki, Shunichi; Nakai, Michiko; Hashimoto, Masakazu; Yasue, Akihiro; Matsuhisa, Munehide; Noji, Sumihare; Fujimura, Tatsuya; Fuchimoto, Dai-ichiro; Otoi, Takeshige

    2016-01-01

    Genetically modified pigs for biomedical applications have been mainly generated using the somatic cell nuclear transfer technique; however, this approach requires complex micromanipulation techniques and sometimes increases the risks of both prenatal and postnatal death by faulty epigenetic reprogramming of a donor somatic cell nucleus. As a result, the production of genetically modified pigs has not been widely applied. We provide a simple method for CRISPR (clustered regularly interspaced short palindromic repeats)/Cas9 gene editing in pigs that involves the introduction of Cas9 protein and single-guide RNA into in vitro fertilized zygotes by electroporation. The use of gene editing by electroporation of Cas9 protein (GEEP) resulted in highly efficient targeted gene disruption and was validated by the efficient production of Myostatin mutant pigs. Because GEEP does not require the complex methods associated with micromanipulation for somatic reprogramming, it has the potential for facilitating the genetic modification of pigs. PMID:27652340

  12. Development of Cells for Generation of Potential Difference from Aloe Vera

    Directory of Open Access Journals (Sweden)

    Yogendra B. Gandole

    2016-01-01

    Full Text Available Today’s need of this modern world is to introduce the renewable, sustainable, pollution free and an efficient energy sources. In this paper, some fundamental investigations are demonstrated for generating an electrical energy from living plants like Aloe Vera. The energy is generated by embedding the electrodes and cells into the plant to allow flow of ions using redox reaction. Here multiple tests have been conducted using different type of electrodes, cells and plants as an attempt to determine the characteristics of the generating system. Though the research work in this field is in infancy, we were able to produce the potential difference of about 1.221V using single pair of electrode and cell. Such hypothesis has been tested at different time of the day and different seasons of the year. Also, lots of new types of materials has been tested and used in combination to give better performance for the development of such a green energy. In future, this green energy could be used for low power electrical and electronic appliances for their operation

  13. Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Nguyen Minh

    2005-12-01

    This report summarizes the work performed by Hybrid Power Generation Systems, LLC (HPGS) under Cooperative Agreement DE-FC2601NT40779 for the US Department of Energy, National Energy Technology Laboratory (DoE/NETL) entitled ''Solid Oxide Fuel Cell Hybrid System for Distributed Power Generation''. The main objective of this project is to develop and demonstrate the feasibility of a highly efficient hybrid system integrating a planar Solid Oxide Fuel Cell (SOFC) and a gas turbine. A conceptual hybrid system design was selected for analysis and evaluation. The selected system is estimated to have over 65% system efficiency, a first cost of approximately $650/kW, and a cost of electricity of 8.4 cents/kW-hr. A control strategy and conceptual control design have been developed for the system. A number of SOFC module tests have been completed to evaluate the pressure impact to performance stability. The results show that the operating pressure accelerates the performance degradation. Several experiments were conducted to explore the effects of pressure on carbon formation. Experimental observations on a functioning cell have verified that carbon deposition does not occur in the cell at steam-to-carbon ratios lower than the steady-state design point for hybrid systems. Heat exchanger design, fabrication and performance testing as well as oxidation testing to support heat exchanger life analysis were also conducted. Performance tests of the prototype heat exchanger yielded heat transfer and pressure drop characteristics consistent with the heat exchanger specification. Multicell stacks have been tested and performance maps were obtained under hybrid operating conditions. Successful and repeatable fabrication of large (>12-inch diameter) planar SOFC cells was demonstrated using the tape calendering process. A number of large area cells and stacks were successfully performance tested at ambient and pressurized conditions. A 25 MW plant configuration was

  14. Genetic engineering of hematopoietic stem cells to generate invariant natural killer T cells.

    Science.gov (United States)

    Smith, Drake J; Liu, Siyuan; Ji, Sunjong; Li, Bo; McLaughlin, Jami; Cheng, Donghui; Witte, Owen N; Yang, Lili

    2015-02-03

    Invariant natural killer T (iNKT) cells comprise a small population of αβ T lymphocytes. They bridge the innate and adaptive immune systems and mediate strong and rapid responses to many diseases, including cancer, infections, allergies, and autoimmunity. However, the study of iNKT cell biology and the therapeutic applications of these cells are greatly limited by their small numbers in vivo (∼0.01-1% in mouse and human blood). Here, we report a new method to generate large numbers of iNKT cells in mice through T-cell receptor (TCR) gene engineering of hematopoietic stem cells (HSCs). We showed that iNKT TCR-engineered HSCs could generate a clonal population of iNKT cells. These HSC-engineered iNKT cells displayed the typical iNKT cell phenotype and functionality. They followed a two-stage developmental path, first in thymus and then in the periphery, resembling that of endogenous iNKT cells. When tested in a mouse melanoma lung metastasis model, the HSC-engineered iNKT cells effectively protected mice from tumor metastasis. This method provides a powerful and high-throughput tool to investigate the in vivo development and functionality of clonal iNKT cells in mice. More importantly, this method takes advantage of the self-renewal and longevity of HSCs to generate a long-term supply of engineered iNKT cells, thus opening up a new avenue for iNKT cell-based immunotherapy.

  15. Increased T cell expression of CD154 (CD40-ligand) in multiple sclerosis

    DEFF Research Database (Denmark)

    Jensen, J; Krakauer, M; Sellebjerg, F

    2001-01-01

    CD154 (CD40-ligand, gp39), expressed on activated T cells, is crucial in T cell-dependent immune responses and may be involved in the pathogenesis of multiple sclerosis (MS). We studied cerebro-spinal fluid and peripheral blood T cell expression of CD154 in MS by flow cytometry. Patients with sec......CD154 (CD40-ligand, gp39), expressed on activated T cells, is crucial in T cell-dependent immune responses and may be involved in the pathogenesis of multiple sclerosis (MS). We studied cerebro-spinal fluid and peripheral blood T cell expression of CD154 in MS by flow cytometry. Patients...

  16. Generation of glycosylphosphatidylinositol anchor protein-deficient blood cells from human induced pluripotent stem cells.

    Science.gov (United States)

    Yuan, Xuan; Braunstein, Evan M; Ye, Zhaohui; Liu, Cyndi F; Chen, Guibin; Zou, Jizhong; Cheng, Linzhao; Brodsky, Robert A

    2013-11-01

    PIG-A is an X-linked gene required for the biosynthesis of glycosylphosphatidylinositol (GPI) anchors; thus, PIG-A mutant cells have a deficiency or absence of all GPI-anchored proteins (GPI-APs). Acquired mutations in hematopoietic stem cells result in the disease paroxysmal nocturnal hemoglobinuria, and hypomorphic germline PIG-A mutations lead to severe developmental abnormalities, seizures, and early death. Human induced pluripotent stem cells (iPSCs) can differentiate into cell types derived from all three germ layers, providing a novel developmental system for modeling human diseases. Using PIG-A gene targeting and an inducible PIG-A expression system, we have established, for the first time, a conditional PIG-A knockout model in human iPSCs that allows for the production of GPI-AP-deficient blood cells. PIG-A-null iPSCs were unable to generate hematopoietic cells or any cells expressing the CD34 marker and were defective in generating mesodermal cells expressing KDR/VEGFR2 (kinase insert domain receptor) and CD56 markers. In addition, PIG-A-null iPSCs had a block in embryonic development prior to mesoderm differentiation that appears to be due to defective signaling through bone morphogenetic protein 4. However, early inducible PIG-A transgene expression allowed for the generation of GPI-AP-deficient blood cells. This conditional PIG-A knockout model should be a valuable tool for studying the importance of GPI-APs in hematopoiesis and human development.

  17. Isolation of a mesenchymal cell population from murine dermis that contains progenitors of multiple cell lineages.

    Science.gov (United States)

    Crigler, Lauren; Kazhanie, Amita; Yoon, Tae-Jin; Zakhari, Julia; Anders, Joanna; Taylor, Barbara; Virador, Victoria M

    2007-07-01

    The skin contains two known subpopulations of stem cells/epidermal progenitors: a basal keratinocyte population found in the interfollicular epithelium and cells residing in the bulge region of the hair follicle. The major role of the interfollicular basal keratinocyte population may be epidermal renewal, whereas the bulge population may only be activated and recruited to form a cutaneous epithelium in case of trauma. Using 3-dimensional cultures of murine skin under stress conditions in which only reserve epithelial cells would be expected to survive and expand, we demonstrate that a mesenchymal population resident in neonatal murine dermis has the unique potential to develop an epidermis in vitro. In monolayer culture, this dermal subpopulation has long-term survival capabilities in restricted serum and an inducible capacity to evolve into multiple cell lineages, both epithelial and mesenchymal, depending on culture conditions. When grafted subcutaneously, this dermal subpopulation gave rise to fusiform structures, reminiscent of disorganized muscle, that stained positive for smooth muscle actin and desmin; on typical epidermal grafts, abundant melanocytes appeared throughout the dermis that were not associated with hair follicles. The multipotential cells can be repeatedly isolated from neonatal murine dermis by a sequence of differential centrifugation and selective culture conditions. These results suggest that progenitors capable of epidermal differentiation exist in the mesenchymal compartment of an abundant tissue source and may have a function in mesenchymal-epithelial transition upon insult. Moreover, these cells could be available in sufficient quantities for lineage determination or tissue engineering applications.

  18. Hit-And-Run enables efficient weight generation for simulation-based multiple criteria decision analysis

    NARCIS (Netherlands)

    Tervonen, Tommi; van Valkenhoef, Gert; Basturk, Nalan; Postmus, Douwe

    2013-01-01

    Models for Multiple Criteria Decision Analysis (MCDA) often separate per-criterion attractiveness evaluation from weighted aggregation of these evaluations across the different criteria. In simulation-based MCDA methods, such as Stochastic Multicriteria Acceptability Analysis, uncertainty in the wei

  19. Regulatory T cell number in multiple sclerosis patients: A meta-analysis.

    Science.gov (United States)

    Noori-Zadeh, Ali; Mesbah-Namin, Seyed Alireza; Bistoon-Beigloo, Sara; Bakhtiyari, Salar; Abbaszadeh, Hojjat-Allah; Darabi, Shahram; Rajabibazl, Masoumeh; Abdanipour, Alireza

    2016-01-01

    Regulatory T cells (Treg cells), defined as CD4(+) CD25(+) FoxP3(+) T cells by expression of CD4, high-affinity IL-2 receptor and the transcription factor, forkhead box P3 (FoxP3). They play a pivotal role in protecting individuals from autoimmunity and a growing body of evidence suggests their role in the prevention of multiple sclerosis development. However, there are discrepancies about the type of defect in the Treg cells of multiple sclerosis patients and especially whether the Treg number alteration could be contributed to multiple sclerosis pathogenesis. Indeed, whether low number of Treg cells can be a risk factor contributing to multiple sclerosis pathogenesis is the matter of debate and there is not any comprehensive agreement on it. Thus, the objective of this systematic review and meta-analysis was to precisely quantify the nature and magnitude of the association between Treg cell number and the risk ratio/odds ratio (OR) of multiple sclerosis in the case-control studies. Hence, medical databases of Embase, PubMed/Medline, PubMed, PubMed Central and SCOPUS were searched for empirical papers using "Regulatory T cell frequency", "Treg frequency" in combination with "multiple sclerosis". In the case-control studies, papers were reviewed for inclusion/exclusion criteria and 8 publications were included. Under random-effect model meta-analysis the data showed that the frequency of Treg cells was not a risk factor in multiple sclerosis using current laboratory methods.

  20. Computer-Generated Holograms for Recording Multiple-Phase-Shifte Fiber Bragg Grating Corrugations

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new method of fabricating multiple-phase-shifte fiber Bragg grating by CGHs is proposed. The authors present an example of such CGH by which a section multiple-phase-shifte fiber Bragg grating with two π/2 phase shifts and grating length L=21.2 μm was produced. The authors describe the production process and finally give an example of a reconstructed fiber grating with two phase-shifts.

  1. Insulin-producing cells generated from dedifferentiated human pancreatic beta cells expanded in vitro.

    Directory of Open Access Journals (Sweden)

    Holger A Russ

    Full Text Available BACKGROUND: Expansion of beta cells from the limited number of adult human islet donors is an attractive prospect for increasing cell availability for cell therapy of diabetes. However, attempts at expanding human islet cells in tissue culture result in loss of beta-cell phenotype. Using a lineage-tracing approach we provided evidence for massive proliferation of beta-cell-derived (BCD cells within these cultures. Expansion involves dedifferentiation resembling epithelial-mesenchymal transition (EMT. Epigenetic analyses indicate that key beta-cell genes maintain open chromatin structure in expanded BCD cells, although they are not transcribed. Here we investigated whether BCD cells can be redifferentiated into beta-like cells. METHODOLOGY/PRINCIPAL FINDING: Redifferentiation conditions were screened by following activation of an insulin-DsRed2 reporter gene. Redifferentiated cells were characterized for gene expression, insulin content and secretion assays, and presence of secretory vesicles by electron microscopy. BCD cells were induced to redifferentiate by a combination of soluble factors. The redifferentiated cells expressed beta-cell genes, stored insulin in typical secretory vesicles, and released it in response to glucose. The redifferentiation process involved mesenchymal-epithelial transition, as judged by changes in gene expression. Moreover, inhibition of the EMT effector SLUG (SNAI2 using shRNA resulted in stimulation of redifferentiation. Lineage-traced cells also gave rise at a low rate to cells expressing other islet hormones, suggesting transition of BCD cells through an islet progenitor-like stage during redifferentiation. CONCLUSIONS/SIGNIFICANCE: These findings demonstrate for the first time that expanded dedifferentiated beta cells can be induced to redifferentiate in culture. The findings suggest that ex-vivo expansion of adult human islet cells is a promising approach for generation of insulin-producing cells for

  2. ATP release, generation and hydrolysis in exocrine pancreatic duct cells.

    Science.gov (United States)

    Kowal, J M; Yegutkin, G G; Novak, I

    2015-12-01

    Extracellular adenosine triphosphate (ATP) regulates pancreatic duct function via P2Y and P2X receptors. It is well known that ATP is released from upstream pancreatic acinar cells. The ATP homeostasis in pancreatic ducts, which secrete bicarbonate-rich fluid, has not yet been examined. First, our aim was to reveal whether pancreatic duct cells release ATP locally and whether they enzymatically modify extracellular nucleotides/sides. Second, we wished to explore which physiological and pathophysiological factors may be important in these processes. Using a human pancreatic duct cell line, Capan-1, and online luminescence measurement, we detected fast ATP release in response to pH changes, bile acid, mechanical stress and hypo-osmotic stress. ATP release following hypo-osmotic stress was sensitive to drugs affecting exocytosis, pannexin-1, connexins, maxi-anion channels and transient receptor potential cation channel subfamily V member 4 (TRPV4) channels, and corresponding transcripts were expressed in duct cells. Direct stimulation of intracellular Ca(2+) and cAMP signalling and ethanol application had negligible effects on ATP release. The released ATP was sequentially dephosphorylated through ecto-nucleoside triphosphate diphosphohydrolase (NTPDase2) and ecto-5'-nucleotidase/CD73 reactions, with respective generation of adenosine diphosphate (ADP) and adenosine and their maintenance in the extracellular medium at basal levels. In addition, Capan-1 cells express counteracting adenylate kinase (AK1) and nucleoside diphosphate kinase (NDPK) enzymes (NME1, 2), which contribute to metabolism and regeneration of extracellular ATP and other nucleotides (ADP, uridine diphosphate (UDP) and uridine triphosphate (UTP)). In conclusion, we illustrate a complex regulation of extracellular purine homeostasis in a pancreatic duct cell model involving: ATP release by several mechanisms and subsequent nucleotide breakdown and ATP regeneration via counteracting nucleotide

  3. Methylseleninic acid potentiates multiple types of cancer cells to ABT-737-induced apoptosis by targeting Mcl-1 and Bad

    DEFF Research Database (Denmark)

    Yin, Shutao; Dong, Yinhui; Li, Jinghua

    2012-01-01

    ABT-737, a novel small molecule inhibitor of Bcl-2 family proteins, holds great promise to complement current cancer therapies. However many types of solid cancer cells are resistant to ABT-737. One practical approach to improve its therapeutic efficacy is to combine with the agents that can...... overcome such resistance to restore the sensitivity. In the present study, a second-generation selenium compound methylseleninic acid (MSeA) synergistically sensitized MDA-MB-231 human breast cancer cells, HT-29 human colon cancer cells and DU145 human prostate cancer cells to apoptosis induction by ABT......-737, as evidenced by greater than additive enhancement of Annexin V/FITC positive (apoptotic) cells and activation of multiple caspases and PARP cleavage. Mechanistic investigation demonstrated that MSeA significantly decreased basal Mcl-1 expression and ABT-737-induced Mcl-1 expression. Knocking down...

  4. An internal ribosome entry site (IRES mutant library for tuning expression level of multiple genes in mammalian cells.

    Directory of Open Access Journals (Sweden)

    Esther Y C Koh

    Full Text Available A set of mutated Encephalomyocarditis virus (EMCV internal ribosome entry site (IRES elements with varying strengths is generated by mutating the translation initiation codons of 10(th, 11(th, and 12(th AUG to non-AUG triplets. They are able to control the relative expression of multiple genes over a wide range in mammalian cells in both transient and stable transfections. The relative strength of each IRES mutant remains similar in different mammalian cell lines and is not gene specific. The expressed proteins have correct molecular weights. Optimization of light chain over heavy chain expression by these IRES mutants enhances monoclonal antibody expression level and quality in stable transfections. Uses of this set of IRES mutants can be extended to other applications such as synthetic biology, investigating interactions between proteins and its complexes, cell engineering, multi-subunit protein production, gene therapy, and reprogramming of somatic cells into stem cells.

  5. Inhibition of Th17 Cell Differentiation as a Treatment for Multiple Sclerosis

    Science.gov (United States)

    2013-10-01

    0736 TITLE: Inhibition of Th17 Cell Differentiation as a Treatment for Multiple Sclerosis PRINCIPAL INVESTIGATOR: Annalisa D’Andrea, PhD...29September2013 4. TITLE AND SUBTITLE Inhibition of Th17 Cell Differentiation as a Treatment for Multiple Sclerosis 5a. CONTRACT NUMBER 5b...were not able to screen compounds. Additionally, experiments aimed to reproduce data showing an association of miR-326 with Th17 cells failed to

  6. Induction and selection of Sox17-expressing endoderm cells generated from murine embryonic stem cells.

    Science.gov (United States)

    Schroeder, Insa S; Sulzbacher, Sabine; Nolden, Tobias; Fuchs, Joerg; Czarnota, Judith; Meisterfeld, Ronny; Himmelbauer, Heinz; Wobus, Anna M

    2012-01-01

    Embryonic stem (ES) cells offer a valuable source for generating insulin-producing cells. However, current differentiation protocols often result in heterogeneous cell populations of various developmental stages. Here we show the activin A-induced differentiation of mouse ES cells carrying a homologous dsRed-IRES-puromycin knock-in within the Sox17 locus into the endoderm lineage. Sox17-expressing cells were selected by fluorescence-assisted cell sorting (FACS) and characterized at the transcript and protein level. Treatment of ES cells with high concentrations of activin A for 10 days resulted in up to 19% Sox17-positive cells selected by FACS. Isolated Sox17-positive cells were characterized by defini- tive endoderm-specific Sox17/Cxcr4/Foxa2 transcripts, but lacked pluripotency-associated Oct4 mRNA and protein. The Sox17-expressing cells showed downregulation of extraembryonic endoderm (Sox7, Afp, Sdf1)-, mesoderm (Foxf1, Meox1)- and ectoderm (Pax6, NeuroD6)-specific transcripts. The presence of Hnf4α, Hes1 and Pdx1 mRNA demonstrated the expression of primitive gut/foregut cell-specific markers. Ngn3, Nkx6.1 and Nkx2.2 transcripts in Sox17-positive cells were determined as properties of pancreatic endocrine progenitors. Immunocytochemistry of activin A-induced Sox17-positive embryoid bodies revealed coexpression of Cxcr4 and Foxa2. Moreover, the histochemical demonstration of E-cadherin-, Cxcr4-, Sox9-, Hnf1β- and Ngn3-positive epithelial-like structures underlined the potential of Sox17-positive cells to further differentiate into the pancreatic lineage. By reducing the heterogeneity of the ES cell progeny, Sox17-expressing cells are a suitable model to evaluate the effects of growth and differentiation factors and of culture conditions to delineate the differentiation process for the generation of pancreatic cells in vitro.

  7. Lenalidomide enhances antigen-specific activity and decreases CD45RA expression of T cells from patients with multiple myeloma.

    Science.gov (United States)

    Neuber, Brigitte; Herth, Isabelle; Tolliver, Claudia; Schoenland, Stefan; Hegenbart, Ute; Hose, Dirk; Witzens-Harig, Mathias; Ho, Anthony D; Goldschmidt, Hartmut; Klein, Bernard; Hundemer, Michael

    2011-07-15

    The aim of this study was to investigate whether the specific T cell response against the multiple myeloma Ag HM1.24 is enhanced by the immunomodulatory drug lenalidomide (Revlimid). Ag-specific CD3(+)CD8(+) T cells against the HM1.24 Ag were expanded in vitro by dendritic cells in 29 healthy donors and 26 patients with plasma cell dyscrasias. Ag-specific activation was analyzed by IFN-γ, granzyme B, and perforin secretion using ELISA, ELISPOT assay, and intracellular staining, and generation of Ag-specific T cells was analyzed by tetramer staining. Expression of T cell maturation markers (CD45RA, CD45R0, CCR7, and CD28) was investigated by flow cytometry. We found that activation of HM1.24-specific T cells from healthy donors and patients with plasma cell dyscrasias was enhanced significantly by lenalidomide and furthermore that the impact of lenalidomide on T cells depends on the duration of the exposure. Notably, lenalidomide supports the downregulation of CD45RA on T cells upon activation, observed in healthy donors and in patients in vitro and also in patients during lenalidomide therapy in vivo. We showed for the first time, to our knowledge, that lenalidomide enhances the Ag-specific activation of T cells and the subsequent downregulation of CD45RA expression of T cells in vitro and in vivo.

  8. Copper anode corrosion affects power generation in microbial fuel cells

    KAUST Repository

    Zhu, Xiuping

    2013-07-16

    Non-corrosive, carbon-based materials are usually used as anodes in microbial fuel cells (MFCs). In some cases, however, metals have been used that can corrode (e.g. copper) or that are corrosion resistant (e.g. stainless steel, SS). Corrosion could increase current through galvanic (abiotic) current production or by increasing exposed surface area, or decrease current due to generation of toxic products from corrosion. In order to directly examine the effects of using corrodible metal anodes, MFCs with Cu were compared with reactors using SS and carbon cloth anodes. MFCs with Cu anodes initially showed high current generation similar to abiotic controls, but subsequently they produced little power (2 mW m-2). Higher power was produced with microbes using SS (12 mW m-2) or carbon cloth (880 mW m-2) anodes, with no power generated by abiotic controls. These results demonstrate that copper is an unsuitable anode material, due to corrosion and likely copper toxicity to microorganisms. © 2013 Society of Chemical Industry.

  9. Key bifurcations of bursting polyrhythms in 3-cell central pattern generators.

    Directory of Open Access Journals (Sweden)

    Jeremy Wojcik

    Full Text Available We identify and describe the key qualitative rhythmic states in various 3-cell network motifs of a multifunctional central pattern generator (CPG. Such CPGs are neural microcircuits of cells whose synergetic interactions produce multiple states with distinct phase-locked patterns of bursting activity. To study biologically plausible CPG models, we develop a suite of computational tools that reduce the problem of stability and existence of rhythmic patterns in networks to the bifurcation analysis of fixed points and invariant curves of a Poincaré return maps for phase lags between cells. We explore different functional possibilities for motifs involving symmetry breaking and heterogeneity. This is achieved by varying coupling properties of the synapses between the cells and studying the qualitative changes in the structure of the corresponding return maps. Our findings provide a systematic basis for understanding plausible biophysical mechanisms for the regulation of rhythmic patterns generated by various CPGs in the context of motor control such as gait-switching in locomotion. Our analysis does not require knowledge of the equations modeling the system and provides a powerful qualitative approach to studying detailed models of rhythmic behavior. Thus, our approach is applicable to a wide range of biological phenomena beyond motor control.

  10. EEN regulates the proliferation and survival of multiple myeloma cells by potentiating IGF-1 secretion

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Er-Wen [Guangzhou Institute of Forensic Science, Guangzhou (China); Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Xue, Sheng-Jiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Li, Xiao-Yan [Department of Pharmacy, The Third Affiliated Hospital, Sun Yat-Sen University, Guangzhou (China); Xu, Suo-Wen [Department of Pharmacology and Toxicology, School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou (China); Cheng, Jian-Ding; Zheng, Jin-Xiang [Department of Forensic Pathology, Zhongshan School of Medicine, Sun Yat-Sen University, Guangzhou (China); Shi, He; Lv, Guo-Li; Li, Zhi-Gang; Li, Yue; Liu, Chang-Hui; Chen, Xiao-Hui; Liu, Hong [Guangzhou Institute of Forensic Science, Guangzhou (China); Li, Jie, E-mail: mdlijie@sina.com [Department of Anaesthesiology, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University, Guangzhou (China); Liu, Chao, E-mail: liuchaogaj@21cn.com [Guangzhou Institute of Forensic Science, Guangzhou (China)

    2014-05-02

    Highlights: • Levels of EEN expression paralleled with the rate of cell proliferation. • EEN was involved in the proliferation and survival of multiple myeloma (MM) cells. • EEN regulated the activity of IGF-1-Akt/mTOR pathway. • EEN regulated proliferation and survival of MM cells by enhancing IGF-1 secretion. - Abstract: The molecular mechanisms of multiple myeloma are not well defined. EEN is an endocytosis-regulating molecule. Here we report that EEN regulates the proliferation and survival of multiple myeloma cells, by regulating IGF-1 secretion. In the present study, we observed that EEN expression paralleled with cell proliferation, EEN accelerated cell proliferation, facilitated cell cycle transition from G1 to S phase by regulating cyclin-dependent kinases (CDKs) pathway, and delayed cell apoptosis via Bcl2/Bax-mitochondrial pathway. Mechanistically, we found that EEN was indispensable for insulin-like growth factor-1 (IGF-1) secretion and the activation of protein kinase B-mammalian target of rapamycin (Akt-mTOR) pathway. Exogenous IGF-1 overcame the phenotype of EEN depletion, while IGF-1 neutralization overcame that of EEN over-expression. Collectively, these data suggest that EEN may play a pivotal role in excessive cell proliferation and insufficient cell apoptosis of bone marrow plasma cells in multiple myeloma. Therefore, EEN may represent a potential diagnostic marker or therapeutic target for multiple myeloma.

  11. Modeling and control of fuel cell based distributed generation systems

    Science.gov (United States)

    Jung, Jin Woo

    This dissertation presents circuit models and control algorithms of fuel cell based distributed generation systems (DGS) for two DGS topologies. In the first topology, each DGS unit utilizes a battery in parallel to the fuel cell in a standalone AC power plant and a grid-interconnection. In the second topology, a Z-source converter, which employs both the L and C passive components and shoot-through zero vectors instead of the conventional DC/DC boost power converter in order to step up the DC-link voltage, is adopted for a standalone AC power supply. In Topology 1, two applications are studied: a standalone power generation (Single DGS Unit and Two DGS Units) and a grid-interconnection. First, dynamic model of the fuel cell is given based on electrochemical process. Second, two full-bridge DC to DC converters are adopted and their controllers are designed: an unidirectional full-bridge DC to DC boost converter for the fuel cell and a bidirectional full-bridge DC to DC buck/boost converter for the battery. Third, for a three-phase DC to AC inverter without or with a Delta/Y transformer, a discrete-time state space circuit model is given and two discrete-time feedback controllers are designed: voltage controller in the outer loop and current controller in the inner loop. And last, for load sharing of two DGS units and power flow control of two DGS units or the DGS connected to the grid, real and reactive power controllers are proposed. Particularly, for the grid-connected DGS application, a synchronization issue between an islanding mode and a paralleling mode to the grid is investigated, and two case studies are performed. To demonstrate the proposed circuit models and control strategies, simulation test-beds using Matlab/Simulink are constructed for each configuration of the fuel cell based DGS with a three-phase AC 120 V (L-N)/60 Hz/50 kVA and various simulation results are presented. In Topology 2, this dissertation presents system modeling, modified space

  12. A Case Report of Multiple Basal Cell Carcinoma Syndrome

    Directory of Open Access Journals (Sweden)

    A. Ansar

    2007-01-01

    Full Text Available Introduction: Nevoid BCC syndrome (Gorline syndrome is a familial disorder with autosomal dominant inheritense. This syndrome is combination of multiple BCC that occurs at an early age, characteristic faces with: frontal bossing, broad nasal bridge and hypertelorism, jaw cysts, palmoplanter pitting, macrocephaly, skeletal and spinal anomalies include bifid ribes, cervical rib and kyphoscoliosis, CNS abnormality include corpus callusom disgenesia , falx cerebri calcification(at early age and mental deficiency.Case Report: This case was a 25-years-old female presented with multiple and progressive skin lesions with different size in neck, upper trunk and axilla (multiple BCC, palmoplantar pitting, jaw cyst, cervical rib, bifid rib and liver haemangioma.Conclusion: With combination of clinical feature, histopathological reports of skin lesions and radiological reports of mandibular cyst and ribs anomalies, this case was diagnosed as nevoid BCC syndrome.

  13. Comparison of clinical course of patients with severe acute respiratory syndrome among the multiple generations of nosocomial transmission

    Institute of Scientific and Technical Information of China (English)

    伍卫; 王景峰; 刘品明; 江山平; 陈庆瑜; 陈为宪; 尹松梅; 严励; 詹俊; 陈锡龙; 李建国

    2004-01-01

    Background Severe acute respiratory syndrome (SARS) is characterized by both an atypical pneumonia and efficient nosocomial transmissin. However, it remains unknown whether the infectivity and the virulence of the pathogen will change throughout the successive transmission. This study was conducted to compare the clinical features and management regimens of patients with SARS among the multiple generations from nosocomial transmission initiated by a super-spreader.Methods The clinical data of 84 epidemiologically-linked SARS patients from a hospital outbreak were retrospectively studied. All patients, in whom a clear-cut transmission generation could be noted, had a direct or indirect exposure to the index patient and the epidemic successively propagated through the multiple generations of cases within a short period of time.Results There were 66 women and 18 men with mean age of (29.2 ± 10.3) years in this cluster; and 96.4% of whom were health care workers. Detailed contact tracing identified 35 (41.7%) first-generation cases, 34 (40.5%) second-generation cases, and 15 (17.8%) third-generation cases. No statistical differences among the multiple generations of transmission were found in terms of age, gender, incubation period and length of hospital stay. With the advanced transmission generations, the initial temperature lowered, the number of cases with dry cough decreased. There were no statistical differences in the peak temperature and duration of fever, other accompanying symptoms, leucopenia; however, the time from initial pulmonary infiltrates to radiographic recovery shortened (P0.05). No statistical differences were found in modes of oxygen therapy and sorts of antibiotics prescribed among the various transmission generations (P>0.05); however, as with the advanced transmission generations, the number of cases prescribed with methylprednisolone, human γ-globulin, interferon-α, antiviral drugs (oral ribavirin or oseltamivir) increased (P<0.05) and time

  14. Multiple layers of B cell memory with different effector functions.

    Science.gov (United States)

    Dogan, Ismail; Bertocci, Barbara; Vilmont, Valérie; Delbos, Frédéric; Mégret, Jérome; Storck, Sébastien; Reynaud, Claude-Agnès; Weill, Jean-Claude

    2009-12-01

    Memory B cells are at the center of longstanding controversies regarding the presence of antigen for their survival and their re-engagement in germinal centers after secondary challenge. Using a new mouse model of memory B cell labeling dependent on the cytidine deaminase AID, we show that after immunization with a particulate antigen, B cell memory appeared in several subsets, comprising clusters of immunoglobulin M-positive (IgM(+)) and IgG1(+) B cells in germinal center-like structures that persisted up to 8 months after immunization, as well as IgM(+) and IgG1(+) B cells with a memory phenotype outside of B cell follicles. After challenge, the IgG subset differentiated into plasmocytes, whereas the IgM subset reinitiated a germinal center reaction. This model, in which B cell memory appears in several layers with different functions, reconciles previous conflicting propositions.

  15. Generation of Entangled States of Multiple Superconducting Quantum Interference Devices in Cavity

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    We propose a scheme for generating the maximally entangled states of many superconducting quantum interference devices (SQUIDs) by using a quantized cavity field and classicalmicrowave pulses in cavity. In the scheme,the maximally entangled states can be generated without requiring the measurement and individual addressing of the SQUIDs.

  16. Generation of mouse chimeras with high contribution of tetraploid embryonic stem cells and embryonic stem cell-fibroblast hybrid cells.

    Science.gov (United States)

    Matveeva, Natalia M; Kizilova, Elena A; Serov, Oleg L

    2015-01-01

    The in vitro long-term cultivation of embryonic stem (ES) cells derived from pre-implantation embryos offers the unique possibility of combining ES cells with pre-implantation embryos to generate chimeras, thus facilitating the creation of a bridge between in vitro and in vivo investigations. Genomic manipulation using ES cells and homologous recombination is one of the most outstanding scientific achievements, resulting in the generation of animals with desirable genome modifications. As such, the generation of ES cells with different ploidy via cell fusion also deserves much attention because this approach allows for the production of chimeras that contain somatic cells with various ploidy. Therefore, this is a powerful tool that can be used to study the role of polyploidy in the normal development of mammals.

  17. The correlation between T regulatory cells and autologous peripheral blood stem cell transplantation in multiple myeloma

    Directory of Open Access Journals (Sweden)

    Ayşe Pınar Erçetin

    2011-06-01

    Full Text Available Objective: Multiple myeloma (MM is characterized by malignant proliferation of plasmocytes and their precursors. T regulatory cells (Tregs have a role in immunosuppression and control of autoimmunity, and are currently an important topic in the study of immune response to tumor cells. The correlation between Tregs and autologous peripheral blood stem cell transplantation (APBSCT in MM has not been studied. The aim of this study was to compare CD4+CD25+FOXP3+ Treg, CD200, and PD-1 levels in MM patients that did and did not undergo APBSCT. Materials and Methods: Peripheral blood samples were collected from 28 MM patients ranging in age from 41 to 78 years for analysis of CD4CD25+ FOXP3+ Tregs, PD-1 (CD279, and CD200. Peripheral blood mononuclear cells were isolated via density gradient centrifugation. Four-color flow cytometry was performed. Using a sequential gating strategy, Tregs were identified as CD4+CD25+FOXP3+ T-cells. Results were analyzed using the Mann Whitney U non-parametric test and a compare means test. p values 0.05. Conclusion: Treg levels were higher in the patients that underwent APBSCT. Tregs are crucial for the induction and maintenance of peripheral tolerance to self-antigens. In addition, Tregs can suppress immune responses to tumor antigens; however, APBSCT and Treg levels were not correlated with CD200 or PD-1 expression. Relationship of Tregs with prognosis needs to be determined by studies that include larger cohorts.

  18. The ROCK inhibitor Y-27632 improves recovery of human embryonic stem cells after fluorescence-activated cell sorting with multiple cell surface markers.

    Directory of Open Access Journals (Sweden)

    Nil Emre

    Full Text Available BACKGROUND: Due to the inherent sensitivity of human embryonic stem cells (hESCs to manipulations, the recovery and survival of hESCs after fluorescence-activated cell sorting (FACS can be low. Additionally, a well characterized and robust methodology for performing FACS on hESCs using multiple-cell surface markers has not been described. The p160-Rho-associated coiled kinase (ROCK inhibitor, Y-27632, previously has been identified as enhancing survival of hESCs upon single-cell dissociation, as well as enhancing recovery from cryopreservation. Here we examined the application of Y-27632 to hESCs after FACS to improve survival in both feeder-dependent and feeder-independent growth conditions. METHODOLOGY/PRINCIPAL FINDINGS: HESCs were sorted using markers for SSEA-3, TRA-1-81, and SSEA-1. Cells were plated after sorting for 24 hours in either the presence or the absence of Y-27632. In both feeder-dependent and feeder-independent conditions, cell survival was greater when Y-27632 was applied to the hESCs after sort. Specifically, treatment of cells with Y-27632 improved post-sort recovery up to four fold. To determine the long-term effects of sorting with and without the application of Y-27632, hESCs were further analyzed. Specifically, hESCs sorted with and without the addition of Y-27632 retained normal morphology, expressed hESC-specific markers as measured by immunocytochemistry and flow cytometry, and maintained a stable karyotype. In addition, the hESCs could differentiate into three germ layers in vitro and in vivo in both feeder-dependent and feeder-independent growth conditions. CONCLUSIONS/SIGNIFICANCE: The application of Y-27632 to hESCs after cell sorting improves cell recovery with no observed effect on pluripotency, and enables the consistent recovery of hESCs by FACS using multiple surface markers. This improved methodology for cell sorting of hESCs will aid many applications such as removal of hESCs from secondary cell types

  19. Generation of human induced pluripotent stem cells from cord blood cells.

    Science.gov (United States)

    Nishishita, Naoki; Takenaka, Chiemi; Fusaki, Noemi; Kawamata, Shin

    2011-01-01

    We report that iPS cells can be safely and effectively generated from fresh human cord blood (CB) cells with Sendai virus (SeV) vector carrying reprogramming factors OCT3/4, SOX2, KLF4, and c-MYC. The SeV vector is a single strand RNA virus having no DNA phase, and selectively infects the freshly isolated CD34+ CD45low+ fraction of CB cells corresponding to hematopoietic progenitors. Approximately twenty ES cell-like colonies emerged from 1 x 104 freshly isolated CD34+ CB cells around 18 days after SeV infection and were selected for passage to reduce the frequency of the remaining SeV-infected cells. The complete elimination of viral constructs was confirmed after several passages by immunostaining with monoclonal antibody against hemagglutinin-neuraminidase (HN) and by RT-PCR analysis. Five ES cell-like clones were selected to examine their in vitro potential for three germ layer differentiation and their capacity for teratoma formation. Generation of non-integrating Sendai virus (SeV) iPS cells from CB cells may be an important step to provide allogeneic iPS cell-derived therapy in the future.

  20. Effector memory and central memory NY-ESO-1-specific re-directed T cells for treatment of multiple myeloma.

    Science.gov (United States)

    Schuberth, P C; Jakka, G; Jensen, S M; Wadle, A; Gautschi, F; Haley, D; Haile, S; Mischo, A; Held, G; Thiel, M; Tinguely, M; Bifulco, C B; Fox, B A; Renner, C; Petrausch, U

    2013-04-01

    The cancer-testis antigen NY-ESO-1 is a potential target antigen for immune therapy expressed in a subset of patients with multiple myeloma. We generated chimeric antigen receptors (CARs) recognizing the immunodominant NY-ESO-1 peptide 157-165 in the context of HLA-A*02:01 to re-direct autologous CD8(+) T cells towards NY-ESO-1(+) myeloma cells. These re-directed T cells specifically lysed NY-ESO-1(157-165)/HLA-A*02:01-positive cells and secreted IFNγ. A total of 40% of CCR7(-) re-directed T cells had an effector memory phenotype and 5% a central memory phenotype. Based on CCR7 cell sorting, effector and memory CAR-positive T cells were separated and CCR7(+) memory cells demonstrated after antigen-specific re-stimulation downregulation of CCR7 as sign of differentiation towards effector cells accompanied by an increased secretion of memory signature cytokines such as IL-2. To evaluate NY-ESO-1 as potential target antigen, we screened 78 bone marrow biopsies of multiple myeloma patients where NY-ESO-1 protein was found to be expressed by immunohistochemistry in 9.7% of samples. Adoptively transferred NY-ESO-1-specific re-directed T cells protected mice against challenge with endogenously NY-ESO-1-positive myeloma cells in a xenograft model. In conclusion, re-directed effector- and central memory T cells specifically recognized NY-ESO-1(157-165)/ HLA-A*02:01-positive cells resulting in antigen-specific functionality in vitro and in vivo.

  1. Very Rapid and Efficient Generation of Induced Pluripotent Stem Cells from Mouse Pre-B Cells.

    Science.gov (United States)

    Di Stefano, Bruno; Graf, Thomas

    2016-01-01

    One of the major obstacles in generating induced pluripotent stem (iPS) cells suitable for therapeutic application is the low efficiency of the process and the long time required, with many iPS lines acquiring genomic aberrations. In this chapter we describe a highly efficient iPS reprogramming system based on the transient expression in pre-B cells of the transcription factor C/EBPα, followed by the induction of the four Yamanaka factors (OSKM). In addition, the process is very rapid, yielding Oct4 positive cells within 2 days and Nanog-positive iPS cell colonies within a week.

  2. Concise review: alchemy of biology: generating desired cell types from abundant and accessible cells.

    Science.gov (United States)

    Pournasr, Behshad; Khaloughi, Keynoush; Salekdeh, Ghasem Hosseini; Totonchi, Mehdi; Shahbazi, Ebrahim; Baharvand, Hossein

    2011-12-01

    A major goal of regenerative medicine is to produce cells to participate in the generation, maintenance, and repair of tissues that are damaged by disease, aging, or trauma, such that function is restored. The establishment of induced pluripotent stem cells, followed by directed differentiation, offers a powerful strategy for producing patient-specific therapies. Given how laborious and lengthy this process can be, the conversion of somatic cells into lineage-specific stem/progenitor cells in one step, without going back to, or through, a pluripotent stage, has opened up tremendous opportunities for regenerative medicine. However, there are a number of obstacles to overcome before these cells can be widely considered for clinical applications. Here, we focus on induced transdifferentiation strategies to convert mature somatic cells to other mature cell types or progenitors, and we summarize the challenges that need to be met if the potential applications of transdifferentiation technology are to be achieved.

  3. Fuel cell generator with fuel electrodes that control on-cell fuel reformation

    Science.gov (United States)

    Ruka, Roswell J.; Basel, Richard A.; Zhang, Gong

    2011-10-25

    A fuel cell for a fuel cell generator including a housing including a gas flow path for receiving a fuel from a fuel source and directing the fuel across the fuel cell. The fuel cell includes an elongate member including opposing first and second ends and defining an interior cathode portion and an exterior anode portion. The interior cathode portion includes an electrode in contact with an oxidant flow path. The exterior anode portion includes an electrode in contact with the fuel in the gas flow path. The anode portion includes a catalyst material for effecting fuel reformation along the fuel cell between the opposing ends. A fuel reformation control layer is applied over the catalyst material for reducing a rate of fuel reformation on the fuel cell. The control layer effects a variable reformation rate along the length of the fuel cell.

  4. Generation of skeletal muscle cells from pluripotent stem cells: advances and challenges.

    Science.gov (United States)

    Abujarour, Ramzey; Valamehr, Bahram

    2015-01-01

    Human pluripotent stem cells (hPSCs) possess unlimited proliferative potential while maintaining the ability to differentiate into any cell type including skeletal muscle cells (SMCs). hPSCs are amenable to genetic editing and can be derived from patient somatic cells, and thus represent a promising option for cell therapies for the treatment of degenerative diseases such as muscular dystrophies. There are unresolved challenges however associated with the derivation and scale-up of hPSCs and generation of differentiated cells in large quantity and high purity. Reported myogenic differentiation protocols are long, require cell sorting and/or rely on ectopic expression of myogenic master regulators. More recent advances have been made with the application of small molecules to enhance the myogenic differentiation efficiency and the identification of more selective markers for the enrichment of myogenic progenitors with enhanced regenerative potential. Here we review the field of myogenic differentiation and highlight areas requiring further research.

  5. Neural progenitor cells from human induced pluripotent stem cells generated less autogenous immune response.

    Science.gov (United States)

    Huang, Ke; Liu, PengFei; Li, Xiang; Chen, ShuBin; Wang, LiHui; Qin, Li; Su, ZhengHui; Huang, WenHao; Liu, Juli; Jia, Bei; Liu, Jie; Cai, JingLei; Pei, DuanQing; Pan, GuangJin

    2014-02-01

    The breakthrough development of induced pluripotent stem cells (iPSCs) raises the prospect of patient-specific treatment for many diseases through the replacement of affected cells. However, whether iPSC-derived functional cell lineages generate a deleterious immune response upon auto-transplantation remains unclear. In this study, we differentiated five human iPSC lines from skin fibroblasts and urine cells into neural progenitor cells (NPCs) and analyzed their immunogenicity. Through co-culture with autogenous peripheral blood mononuclear cells (PBMCs), we showed that both somatic cells and iPSC-derived NPCs do not stimulate significant autogenous PBMC proliferation. However, a significant immune reaction was detected when these cells were co-cultured with allogenous PBMCs. Furthermore, no significant expression of perforin or granzyme B was detected following stimulation of autogenous immune effector cells (CD3(+)CD8(-) T cells, CD3(+)CD8(+) T cells or CD3(-)CD56(+) NK cells) by NPCs in both PBMC and T cell co-culture systems. These results suggest that human iPSC-derived NPCs may not initiate an immune response in autogenous transplants, and thus set a base for further preclinical evaluation of human iPSCs.

  6. Multiple personalities: synaptic target cells as introverts and extroverts.

    Science.gov (United States)

    Ritzenthaler, S; Chiba, A

    2001-10-01

    The intricate process of wiring a neuronetwork requires a high degree of accuracy in the communication between pre- and post-synaptic cells. While presynaptic cells have been widely recognized for their dynamic role in synaptic matchmaking, post-synaptic cells have historically been overlooked as passive targets. Recent studies in the Drosophila embryonic neuromuscular system provide compelling evidence that post-synaptic cells participate actively in the synaptogenic process. Endocytosis allows them to quickly modify the array of molecular cues they provide on their surfaces and the extension of dynamic filopodia allows post-synaptic cells to engage in direct long-distance communication. By making use of familiar cellular mechanisms such as endocytosis and filopodia formation, post-synaptic cells may be able to communicate more effectively with potential synaptic partners.

  7. Multiple Effects of Berberine Derivatives on Colon Cancer Cells

    Directory of Open Access Journals (Sweden)

    Luis Miguel Guamán Ortiz

    2014-01-01

    Full Text Available The pharmacological use of the plant alkaloid berberine is based on its antibacterial and anti-inflammatory properties; recently, anticancer activity has been attributed to this compound. To exploit this interesting feature, we synthesized three berberine derivatives, namely, NAX012, NAX014, and NAX018, and we tested their effects on two human colon carcinoma cell lines, that is, HCT116 and SW613-B3, which are characterized by wt and mutated p53, respectively. We observed that cell proliferation is more affected by cell treatment with the derivatives than with the lead compound; moreover, the derivatives proved to induce cell cycle arrest and cell death through apoptosis, thus suggesting that they could be promising anticancer drugs. Finally, we detected typical signs of autophagy in cells treated with berberine derivatives.

  8. Activation of endogenous neural stem cells for multiple sclerosis therapy

    NARCIS (Netherlands)

    Michailidou, Iliana; de Vries, Helga E.; Hol, Elly M.; van Strien, Miriam E.

    2015-01-01

    Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system, leading to severe neurological deficits. Current MS treatment regimens, consist of immunomodulatory agents aiming to reduce the rate of relapses. However, these agents are usually insufficient to treat chronic

  9. Activation of endogenous neural stem cells for multiple sclerosis therapy

    NARCIS (Netherlands)

    Michailidou, I.; de Vries, H.E.; Hol, E.M.; van Strien, M.E.

    2014-01-01

    Multiple sclerosis (MS) is a chronic inflammatory disorder of the central nervous system, leading to severe neurological deficits. Current MS treatment regimens, consist of immunomodulatory agents aiming to reduce the rate of relapses. However, these agents are usually insufficient to treat chronic

  10. Generation of kidney organoids from human pluripotent stem cells.

    Science.gov (United States)

    Takasato, Minoru; Er, Pei X; Chiu, Han S; Little, Melissa H

    2016-09-01

    The human kidney develops from four progenitor populations-nephron progenitors, ureteric epithelial progenitors, renal interstitial progenitors and endothelial progenitors-resulting in the formation of maximally 2 million nephrons. Until recently, the reported methods differentiated human pluripotent stem cells (hPSCs) into either nephron progenitor or ureteric epithelial progenitor cells, consequently forming only nephrons or collecting ducts, respectively. Here we detail a protocol that simultaneously induces all four progenitors to generate kidney organoids within which segmented nephrons are connected to collecting ducts and surrounded by renal interstitial cells and an endothelial network. As evidence of functional maturity, proximal tubules within organoids display megalin-mediated and cubilin-mediated endocytosis, and they respond to a nephrotoxicant to undergo apoptosis. This protocol consists of 7 d of monolayer culture for intermediate mesoderm induction, followed by 18 d of 3D culture to facilitate self-organizing renogenic events leading to organoid formation. Personnel experienced in culturing hPSCs are required to conduct this protocol.

  11. Full-potential multiple scattering theory with space-filling cells for bound and continuum states.

    Science.gov (United States)

    Hatada, Keisuke; Hayakawa, Kuniko; Benfatto, Maurizio; Natoli, Calogero R

    2010-05-12

    We present a rigorous derivation of a real-space full-potential multiple scattering theory (FP-MST) that is free from the drawbacks that up to now have impaired its development (in particular the need to expand cell shape functions in spherical harmonics and rectangular matrices), valid both for continuum and bound states, under conditions for space partitioning that are not excessively restrictive and easily implemented. In this connection we give a new scheme to generate local basis functions for the truncated potential cells that is simple, fast, efficient, valid for any shape of the cell and reduces to the minimum the number of spherical harmonics in the expansion of the scattering wavefunction. The method also avoids the need for saturating 'internal sums' due to the re-expansion of the spherical Hankel functions around another point in space (usually another cell center). Thus this approach provides a straightforward extension of MST in the muffin-tin (MT) approximation, with only one truncation parameter given by the classical relation l(max) = kR(b), where k is the electron wavevector (either in the excited or ground state of the system under consideration) and R(b) is the radius of the bounding sphere of the scattering cell. Moreover, the scattering path operator of the theory can be found in terms of an absolutely convergent procedure in the l(max) --> ∞ limit. Consequently, this feature provides a firm ground for the use of FP-MST as a viable method for electronic structure calculations and makes possible the computation of x-ray spectroscopies, notably photo-electron diffraction, absorption and anomalous scattering among others, with the ease and versatility of the corresponding MT theory. Some numerical applications of the theory are presented, both for continuum and bound states.

  12. Ras proteins have multiple functions in vegetative cells of Dictyostelium.

    Science.gov (United States)

    Bolourani, Parvin; Spiegelman, George; Weeks, Gerald

    2010-11-01

    During the aggregation of Dictyostelium cells, signaling through RasG is more important in regulating cyclic AMP (cAMP) chemotaxis, whereas signaling through RasC is more important in regulating the cAMP relay. However, RasC is capable of substituting for RasG for chemotaxis, since rasG⁻ cells are only partially deficient in chemotaxis, whereas rasC⁻/rasG⁻ cells are totally incapable of chemotaxis. In this study we have examined the possible functional overlap between RasG and RasC in vegetative cells by comparing the vegetative cell properties of rasG⁻, rasC⁻, and rasC⁻/rasG⁻ cells. In addition, since RasD, a protein not normally found in vegetative cells, is expressed in vegetative rasG⁻ and rasC⁻/rasG⁻ cells and appears to partially compensate for the absence of RasG, we have also examined the possible functional overlap between RasG and RasD by comparing the properties of rasG⁻ and rasC⁻/rasG⁻ cells with those of the mutant cells expressing higher levels of RasD. The results of these two lines of investigation show that RasD is capable of totally substituting for RasG for cytokinesis and growth in suspension, whereas RasC is without effect. In contrast, for chemotaxis to folate, RasC is capable of partially substituting for RasG, but RasD is totally without effect. Finally, neither RasC nor RasD is able to substitute for the role that RasG plays in regulating actin distribution and random motility. These specificity studies therefore delineate three distinct and none-overlapping functions for RasG in vegetative cells.

  13. Different aspects of thalidomide treatment and stem cell transplantation in multiple myeloma patients

    NARCIS (Netherlands)

    Marion, A.M.W. van

    2006-01-01

    Multiple myeloma (MM) is an haematological malignancy caused by an unrestrained proliferation of plasma cells (monoclonally differentiated B-cells), and part of the white blood cell count. This proliferation infiltrates the blood forming skeletal bone marrow, producing osteoclastic factors, causing

  14. B cell antigen presentation is sufficient to drive neuroinflammation in an animal model of multiple sclerosis.

    Science.gov (United States)

    Parker Harp, Chelsea R; Archambault, Angela S; Sim, Julia; Ferris, Stephen T; Mikesell, Robert J; Koni, Pandelakis A; Shimoda, Michiko; Linington, Christopher; Russell, John H; Wu, Gregory F

    2015-06-01

    B cells are increasingly regarded as integral to the pathogenesis of multiple sclerosis, in part as a result of the success of B cell-depletion therapy. Multiple B cell-dependent mechanisms contributing to inflammatory demyelination of the CNS have been explored using experimental autoimmune encephalomyelitis (EAE), a CD4 T cell-dependent animal model for multiple sclerosis. Although B cell Ag presentation was suggested to regulate CNS inflammation during EAE, direct evidence that B cells can independently support Ag-specific autoimmune responses by CD4 T cells in EAE is lacking. Using a newly developed murine model of in vivo conditional expression of MHC class II, we reported previously that encephalitogenic CD4 T cells are incapable of inducing EAE when B cells are the sole APC. In this study, we find that B cells cooperate with dendritic cells to enhance EAE severity resulting from myelin oligodendrocyte glycoprotein (MOG) immunization. Further, increasing the precursor frequency of MOG-specific B cells, but not the addition of soluble MOG-specific Ab, is sufficient to drive EAE in mice expressing MHCII by B cells alone. These data support a model in which expansion of Ag-specific B cells during CNS autoimmunity amplifies cognate interactions between B and CD4 T cells and have the capacity to independently drive neuroinflammation at later stages of disease.

  15. Generation of induced pluripotent stem cells from bovine embryonic fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    Xiaoping Han; Ning Li; Jianyong Han; Fangrong Ding; Suying Cao; Seong Soo Lim; Yunping Dai; Ran Zhang; Yurui Zhang; Bing Lim

    2011-01-01

    Dear Editor,Embryonic stem cell (ES cell) lines were first generated by culturing mouse inner cell mass (ICM) on feeder layers in 1981 [1].However,in large domestic animals,attempts to establish ES cell lines from ICM of blastocysts or the later epiblast have not been successful.This has hindered the efficient production of genetically modified livestocks by using ES-based approaches.Recently,it was found that ectopic expression of various combinations oftranscriptinn factors is able to reprogram somatic cells to a pluripotent state [2-5].These induced pluripotent stem (iPS) cells show similarities to embryo-derived ES cells and can be used to produce viable mice through tetraploid complementation [6,7].So far,iPS cells of several mammalian species have been successfully generated [2,3,8-12].In this letter,we report the first establishment of bovine iPS cells using defined transcription factors and a modified culture medium.

  16. Biomimetic heterogeneous multiple ion channels: a honeycomb structure composite film generated by breath figures

    Science.gov (United States)

    Han, Keyu; Heng, Liping; Wen, Liping; Jiang, Lei

    2016-06-01

    We design a novel type of artificial multiple nanochannel system with remarkable ion rectification behavior via a facile breath figure (BF) method. Notably, even though the charge polarity in the channel wall reverses under different pH values, this nanofluidic device displays the same ionic rectification direction. Compared with traditional nanochannels, this composite multiple ion channel device can be more easily obtained and has directional ionic rectification advantages, which can be applied in many fields.We design a novel type of artificial multiple nanochannel system with remarkable ion rectification behavior via a facile breath figure (BF) method. Notably, even though the charge polarity in the channel wall reverses under different pH values, this nanofluidic device displays the same ionic rectification direction. Compared with traditional nanochannels, this composite multiple ion channel device can be more easily obtained and has directional ionic rectification advantages, which can be applied in many fields. Electronic supplementary information (ESI) available: Pore size distribution histograms of the AAO substrates; SEM images of the side view of pure AAO membranes and top view of the flat PI/AAO composite film; the current-time curves of the flat composite film; the current-voltage characteristics curves of pure AAO nanochannels with different mean pore diameters; CA of the two surfaces of the composite PI/AAO film, the structural formula of the polymer polyimide resin (PI), and solid surface zeta potential. See DOI: 10.1039/c6nr02506d

  17. WORKING FEATURES OF POWER SOURCE SYSTEMS – A MULTIPLE CURRENT PULSE GENERATOR

    Directory of Open Access Journals (Sweden)

    Shs.V. Argun

    2013-04-01

    Full Text Available An analysis of circuit designs as to connecting a magnetic pulse action tool to a power source has been carried out. Design features of a magnetic pulse installation control and monitoring system in a multiple current pulse mode have been revealed. The description of the control and monitoring system block diagrams has been presented.

  18. Advances in understanding the cell types and approaches used for generating induced pluripotent stem cells.

    Science.gov (United States)

    Li, Jun; Song, Wei; Pan, Guangjin; Zhou, Jun

    2014-07-19

    Successfully reprogramming somatic cells to a pluripotent state generates induced pluripotent stem (iPS) cells (or iPSCs), which have extensive self-renewal capacity like embryonic stem cells (ESCs). iPSCs can also generate daughter cells that can further undergo differentiation into various lineages or terminally differentiate to reach their final functional state. The discovery of how to produce iPSCs opened a new field of stem cell research with both intellectual and therapeutic benefits. The huge potential implications of disease-specific or patient-specific iPSCs have impelled scientists to solve problems hindering their applications in clinical medicine, especially the issues of convenience and safety. To determine the range of tissue types amenable to reprogramming as well as their particular characteristics, cells from three embryonic germ layers have been assessed, and the advantages that some tissue origins have over fibroblast origins concerning efficiency and accessibility have been elucidated. To provide safe iPSCs in an efficient and convenient way, the delivery systems and combinations of inducing factors as well as the chemicals used to generate iPSCs have also been significantly improved in addition to the efforts on finding better donor cells. Currently, iPSCs can be generated without c-Myc and Klf4 oncogenes, and non-viral delivery integration-free chemically mediated reprogramming methods have been successfully employed with relatively satisfactory efficiency. This paper will review recent advances in iPS technology by highlighting tissue origin and generation of iPSCs. The obstacles that need to be overcome for clinical applications of iPSCs are also discussed.

  19. Multiple loci are associated with white blood cell phenotypes

    NARCIS (Netherlands)

    M.A. Nalls (Michael); D. Couper (David); T. Tanaka (Toshiko); F.J.A. van Rooij (Frank); M-H. Chen (Ming-Huei); A.V. Smith (Albert Vernon); D. Toniolo (Daniela); N.A. Zakai (Neil); Q. Yang (Qiong Fang); A. Greinacher (Andreas); A.R. Wood (Andrew); M. Garcia (Melissa); P. Gasparini (Paolo); Y. Liu (Yongmei); T. Lumley (Thomas); A.R. Folsom (Aaron); A.P. Reiner (Alex); C. Gieger (Christian); V. Lagou (Vasiliki); J.F. Felix (Janine); H. Völzke (Henry); N.A. Gouskova (Natalia); A. Biffi (Alessandro); A. Döring (Angela); U. Völker (Uwe); S. Chong (Sean); K.L. Wiggins (Kerri); A. Rendon (Augusto); A. Dehghan (Abbas); M. Moore (Matt); K.D. Taylor (Kent); J.G. Wilson (James); G. Lettre (Guillaume); A. Hofman (Albert); J.C. Bis (Joshua); N. Pirastu (Nicola); C.S. Fox (Caroline); C. Meisinger (Christa); J.G. Sambrook (Jennifer); S. Arepalli (Sampath); M. Nauck (Matthias); H. Prokisch (Holger); J. Stephens (Jonathan); N.L. Glazer (Nicole); L.A. Cupples (Adrienne); Y. Okada (Yukinori); A. Takahashi (Atsushi); Y. Kamatani (Yoichiro); K. Matsuda (Koichi); T. Tsunoda (Tatsuhiko); M. Kubo (Michiaki); Y. Nakamura (Yusuke); K. Yamamoto (Kazuhiko); M. Stumvoll (Michael); A. Tönjes (Anke); I. Prokopenko (Inga); T. Illig (Thomas); K.V. Patel (Kushang); S.F. Garner (Stephen); B. Kuhnel (Brigitte); M. Mangino (Massimo); B.A. Oostra (Ben); S.L. Thein; J. Coresh (Josef); H.E. Wichmann (Heinz Erich); S. Menzel (Stephan); J. Lin; G. Pistis (Giorgio); A.G. Uitterlinden (André); T.D. Spector (Timothy); A. Teumer (Alexander); G. Eiriksdottir (Gudny); V. Gudnason (Vilmundur); S. Bandinelli (Stefania); T.M. Frayling (Timothy); A. Chakravarti (Aravinda); P. Tikka-Kleemola (Päivi); D. Melzer (David); W.H. Ouwehand (Willem); D. Levy (Daniel); E.A. Boerwinkle (Eric); A. Singleton (Andrew); D.G. Hernandez (Dena); D.L. Longo (Dan); N. Soranzo (Nicole); J.C.M. Witteman (Jacqueline); B.M. Psaty (Bruce); L. Ferrucci (Luigi); T.B. Harris (Tamara); C.J. O'Donnell (Christopher); S.K. Ganesh (Santhi)

    2011-01-01

    textabstractWhite blood cell (WBC) count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types.

  20. Multiple factors conferring high radioresistance in insect Sf9 cells.

    Science.gov (United States)

    Cheng, I-Cheng; Lee, How-Jing; Wang, T C

    2009-05-01

    Sf9, a lepidopteran cell line isolated from the fall armyworm, Spodoptera frugiperda, was shown to be significantly more resistant to growth inhibition and apoptosis induction effects of x-ray irradiation than several human cell lines of different origins. The single-cell electrophoresis technique revealed that Sf9 cells showed lower x-ray irradiation-induced DNA damage as well as better efficiency at repairing these damages. In addition, Sf9 cells were lower in both background and x-ray irradiation-induced intracellular oxidative stress, in which the higher intracellular level of reduced glutathione seemed to play a major role. The significance of oxidative stress in determining the radioresistance of Sf9 cells was confirmed by their being more resistant to hydrogen peroxide while equally susceptible to other non-reactive oxygen species of N-nitroso alkylating agents when compared with a human cell line. Although the Sf9 and human cell lines were equally susceptible to the lethal effects of N-nitroso alkylating agents, the components of DNA damage-induced and the repair enzymes involved significantly differ. This phenomenon is also discussed in this report.

  1. Generation and Characterization of Erythroid Cells from Human Embryonic Stem Cells and Induced Pluripotent Stem Cells: An Overview

    Directory of Open Access Journals (Sweden)

    Kai-Hsin Chang

    2011-01-01

    Full Text Available Because of the imbalance in the supply and demand of red blood cells (RBCs, especially for alloimmunized patients or patients with rare blood phenotypes, extensive research has been done to generate therapeutic quantities of mature RBCs from hematopoietic stem cells of various sources, such as bone marrow, peripheral blood, and cord blood. Since human embryonic stem cells (hESCs and induced pluripotent stem cells (iPSCs can be maintained indefinitely in vitro, they represent potentially inexhaustible sources of donor-free RBCs. In contrast to other ex vivo stem-cell-derived cellular therapeutics, tumorigenesis is not a concern, as RBCs can be irradiated without marked adverse effects on in vivo function. Here, we provide a comprehensive review of the recent publications relevant to the generation and characterization of hESC- and iPSC-derived erythroid cells and discuss challenges to be met before the eventual realization of clinical usage of these cells.

  2. Efficient generation of lens progenitor cells from cataract patient-specific induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Xiaodi Qiu

    Full Text Available The development of a technique to induce the transformation of somatic cells to a pluripotent state via the ectopic expression of defined transcription factors was a transformational event in the field of regenerative medicine. The development of this technique also impacted ophthalmology, as patient-specific induced pluripotent stemcells (iPSCs may be useful resources for some ophthalmological diseases. The lens is a key refractive element in the eye that focuses images of the visual world onto the retina. To establish a new model for drug screening to treat lens diseases and investigating lens aging and development, we examined whether human lens epithelial cells (HLECs could be induced into iPSCs and if lens-specific differentiation of these cells could be achieved under defined chemical conditions. We first efficiently reprogrammed HLECs from age-related cataract patients to iPSCs with OCT-4, SOX-2, and KLF-4. The resulting HLEC-derived iPS (HLE-iPS colonies were indistinguishable from human ES cells with respect to morphology, gene expression, pluripotent marker expression and their ability to generate all embryonic germ-cell layers. Next, we performed a 3-step induction procedure: HLE-iPS cells were differentiated into large numbers of lens progenitor-like cells with defined factors (Noggin, BMP and FGF2, and we determined that these cells expressed lens-specific markers (PAX6, SOX2, SIX3, CRYAB, CRYAA, BFSP1, and MIP. In addition, HLE-iPS-derived lens cells exhibited reduced expression of epithelial mesenchymal transition (EMT markers compared with human embryonic stem cells (hESCs and fibroblast-derived iPSCs. Our study describes a highly efficient procedure for generating lens progenitor cells from cataract patient HLEC-derived iPSCs. These patient-derived pluripotent cells provide a valuable model for studying the developmental and molecular biological mechanisms that underlie cell determination in lens development and cataract

  3. A Progenitor Cell Expressing Transcription Factor RORγt Generates All Human Innate Lymphoid Cell Subsets.

    Science.gov (United States)

    Scoville, Steven D; Mundy-Bosse, Bethany L; Zhang, Michael H; Chen, Li; Zhang, Xiaoli; Keller, Karen A; Hughes, Tiffany; Chen, Luxi; Cheng, Stephanie; Bergin, Stephen M; Mao, Hsiaoyin C; McClory, Susan; Yu, Jianhua; Carson, William E; Caligiuri, Michael A; Freud, Aharon G

    2016-05-17

    The current model of murine innate lymphoid cell (ILC) development holds that mouse ILCs are derived downstream of the common lymphoid progenitor through lineage-restricted progenitors. However, corresponding lineage-restricted progenitors in humans have yet to be discovered. Here we identified a progenitor population in human secondary lymphoid tissues (SLTs) that expressed the transcription factor RORγt and was unique in its ability to generate all known ILC subsets, including natural killer (NK) cells, but not other leukocyte populations. In contrast to murine fate-mapping data, which indicate that only ILC3s express Rorγt, these human progenitor cells as well as human peripheral blood NK cells and all mature ILC populations expressed RORγt. Thus, all human ILCs can be generated through an RORγt(+) developmental pathway from a common progenitor in SLTs. These findings help establish the developmental signals and pathways involved in human ILC development.

  4. Generation of red blood cells from human induced pluripotent stem cells.

    Science.gov (United States)

    Dias, Jessica; Gumenyuk, Marina; Kang, HyunJun; Vodyanik, Maxim; Yu, Junying; Thomson, James A; Slukvin, Igor I

    2011-09-01

    Differentiation of human induced pluripotent stem cells (hiPSCs) and embryonic stem cells (hESCs) into the erythroid lineage of cells offers a novel opportunity to study erythroid development, regulation of globin switching, drug testing, and modeling of red blood cell (RBC) diseases in vitro. Here we describe an approach for the efficient generation of RBCs from hiPSC/hESCs using an OP9 coculture system to induce hematopoietic differentiation followed by selective expansion of erythroid cells in serum-free media with erythropoiesis-supporting cytokines. We showed that fibroblast-derived transgenic hiPSCs generated using lentivirus-based vectors and transgene-free hiPSCs generated using episomal vectors can be differentiated into RBCs with an efficiency similar to that of H1 hESCs. Erythroid cultures established with this approach consisted of an essentially pure population of CD235a(+)CD45(-) leukocyte-free RBCs with robust expansion potential and long life span (up to 90 days). Similar to hESCs, hiPSC-derived RBCs expressed predominately fetal γ and embryonic ɛ globins, indicating complete reprogramming of β-globin locus following transition of fibroblasts to the pluripotent state. Although β-globin expression was detected in hiPSC/hESC-derived erythroid cells, its expression was substantially lower than the embryonic and fetal globins. Overall, these results demonstrate the feasibility of large-scale production of erythroid cells from fibroblast-derived hiPSCs, as has been described for hESCs. Since RBCs generated from transgene-free hiPSCs lack genomic integration and background expression of reprogramming genes, they would be a preferable cell source for modeling of diseases and for gene function studies.

  5. Electricity generation from the mud by using microbial fuel cell

    Directory of Open Access Journals (Sweden)

    Idris Sitinoor Adeib

    2016-01-01

    Full Text Available Microbial fuel cells (MFCs is a bio-electrochemical device that harnesses the power of respiring microbes to convert organic substrates directly into electrical energy. This is achieved when bacteria transfer electrons to an electrode rather than directly to an electron acceptor. Their technical feasibility has recently been proven and there is great enthusiasm in the scientific community that MFCs could provide a source of “green electricity”. Microbial fuel cells work by allowing bacteria to do what they do best, oxidize and reduce organic molecules. Bacterial respiration is basically one big redox reaction in which electrons are being moved around. The objective is to generate electricity throughout the biochemical process using chemical waste basically sludge, via microbial fuel cells. The methodology includes collecting sludge from different locations, set up microbial fuel cells with the aid of salt bridge and observing the results in voltage measurement. The microbial fuel cells consist of two chambers, iron electrodes, copper wire, air pump (to increase the efficiency of electron transfer, water, sludge and salt bridge. After several observations, it is seen that this MFC can achieve up until 202 milivolts (0.202volts with the presence of air pump. It is proven through the experiments that sludge from different locations gives different results in term of the voltage measurement. This is basically because in different locations of sludge contain different type and amount of nutrients to provide the growth of bacteria. Apart from that, salt bridge also play an important role in order to transport the proton from cathode to anode. A longer salt bridge will give a higher voltage compared to a short salt bridge. On the other hand, the limitations that this experiment facing is the voltage that being produced did not last long as the bacteria activity slows down gradually and the voltage produced are not really great in amount. Lastly to

  6. Next Generation Bipolar Plates for Automotive PEM Fuel Cells

    Energy Technology Data Exchange (ETDEWEB)

    Adrianowycz, Orest; Norley, Julian; Stuart, David J; Flaherty, David; Wayne, Ryan; ; Williams, Warren; Tietze, Roger; Nguyen, Yen-Loan H; Zawodzinski, Tom; Pietrasz, Patrick

    2010-04-15

    The results of a successful U.S. Department of Energy (DoE) funded two-year $2.9 MM program lead by GrafTech International Inc. (GrafTech) are reported and summarized. The program goal was to develop the next generation of high temperature proton exchange membrane (PEM) fuel cell bipolar plates for use in transportation fuel cell applications operating at temperatures up to 120 °C. The bipolar plate composite developed during the program is based on GrafTech’s GRAFCELL resin impregnated flexible graphite technology and makes use of a high temperature Huntsman Advanced Materials resin system which extends the upper use temperature of the composite to the DoE target. High temperature performance of the new composite is achieved with the added benefit of improvements in strength, modulus, and dimensional stability over the incumbent resin systems. Other physical properties, including thermal and electrical conductivity of the new composite are identical to or not adversely affected by the new resin system. Using the new bipolar plate composite system, machined plates were fabricated and tested in high temperature single-cell fuel cells operating at 120 °C for over 1100 hours by Case Western Reserve University. Final verification of performance was done on embossed full-size plates which were fabricated and glued into bipolar plates by GrafTech. Stack testing was done on a 10-cell full-sized stack under a simulated drive cycle protocol by Ballard Power Systems. Freeze-thaw performance was conducted by Ballard on a separate 5-cell stack and shown to be within specification. A third stack was assembled and shipped to Argonne National Laboratory for independent performance verification. Manufacturing cost estimate for the production of the new bipolar plate composite at current and high volume production scenarios was performed by Directed Technologies Inc. (DTI). The production cost estimates were consistent with previous DoE cost estimates performed by DTI for the

  7. Micro-RNA dysregulation in multiple sclerosis favours pro-inflammatory T-cell-mediated autoimmunity.

    Science.gov (United States)

    Guerau-de-Arellano, Mireia; Smith, Kristen M; Godlewski, Jakub; Liu, Yue; Winger, Ryan; Lawler, Sean E; Whitacre, Caroline C; Racke, Michael K; Lovett-Racke, Amy E

    2011-12-01

    Pro-inflammatory T cells mediate autoimmune demyelination in multiple sclerosis. However, the factors driving their development and multiple sclerosis susceptibility are incompletely understood. We investigated how micro-RNAs, newly described as post-transcriptional regulators of gene expression, contribute to pathogenic T-cell differentiation in multiple sclerosis. miR-128 and miR-27b were increased in naïve and miR-340 in memory CD4(+) T cells from patients with multiple sclerosis, inhibiting Th2 cell development and favouring pro-inflammatory Th1 responses. These effects were mediated by direct suppression of B lymphoma Mo-MLV insertion region 1 homolog (BMI1) and interleukin-4 (IL4) expression, resulting in decreased GATA3 levels, and a Th2 to Th1 cytokine shift. Gain-of-function experiments with these micro-RNAs enhanced the encephalitogenic potential of myelin-specific T cells in experimental autoimmune encephalomyelitis. In addition, treatment of multiple sclerosis patient T cells with oligonucleotide micro-RNA inhibitors led to the restoration of Th2 responses. These data illustrate the biological significance and therapeutic potential of these micro-RNAs in regulating T-cell phenotypes in multiple sclerosis.

  8. Enhanced performance of InGaN/GaN multiple quantum well solar cells with double indium content

    Institute of Scientific and Technical Information of China (English)

    Zhao Bi-Jun; Chen Xin; Ren Zhi-Wei; Tong Jin-Hui; Wang Xing-Fu; Li Dan-Wei; Zhuo Xiang-Jing

    2013-01-01

    The performance of a multiple quantum well (MQW) InGaN solar cell with double indium content is investigated.It is found that the adoption of a double indium structure can effectively broaden the spectral response of the external quantum efficiencies and optimize the overall performance of the solar cell.Under AM1.5G illumination,the short-circuit current density (Jsc) and conversion efficiency of the solar cell are enhanced by 65% and 13% compared with those of a normal single-indium-content MQW solar cell.These improvements are mainly attributed to the expansion of the absorption spectrum and better extraction efficiency of the photon-generated carriers induced by higher polarization.

  9. Power generation from furfural using the microbial fuel cell

    Science.gov (United States)

    Luo, Yong; Liu, Guangli; Zhang, Renduo; Zhang, Cuiping

    Furfural is a typical inhibitor in the ethanol fermentation process using lignocellulosic hydrolysates as raw materials. In the literature, no report has shown that furfural can be utilized as the fuel to produce electricity in the microbial fuel cell (MFC), a device that uses microbes to convert organic compounds to generate electricity. In this study, we demonstrated that electricity was successfully generated using furfural as the sole fuel in both the ferricyanide-cathode MFC and the air-cathode MFC. In the ferricyanide-cathode MFC, the maximum power densities reached 45.4, 81.4, and 103 W m -3, respectively, when 1000 mg L -1 glucose, a mixture of 200 mg L -1 glucose and 5 mM furfural, and 6.68 mM furfural were used as the fuels in the anode solution. The corresponding Coulombic efficiencies (CE) were 4.0, 7.1, and 10.2% for the three treatments, respectively. For pure furfural as the fuel, the removal efficiency of furfural reached up to 95% within 12 h. In the air-cathode MFC using 6.68 mM furfural as the fuel, the maximum values of power density and CE were 361 mW m -2 (18 W m -3) and 30.3%, respectively, and the COD removal was about 68% at the end of the experiment (about 30 h). Increase in furfural concentrations from 6.68 to 20 mM resulted in increase in the maximum power densities from 361 to 368 mW m -2, and decrease in CEs from 30.3 to 20.6%. These results indicated that some toxic and biorefractory organics such as furfural might still be suitable resources for electricity generation using the MFC technology.

  10. Reducing Excessive Amounts of Data: Multiple Web Queries for Generation of Pun Candidates

    Directory of Open Access Journals (Sweden)

    Pawel Dybala

    2011-01-01

    Full Text Available Humor processing is still a less studied issue, both in NLP and AI. In this paper we contribute to this field. In our previous research we showed that adding a simple pun generator to a chatterbot can significantly improve its performance. The pun generator we used generated only puns based on words (not phrases. In this paper we introduce the next stage of the system's development—an algorithm allowing generation of phrasal pun candidates. We show that by using only the Internet (without any hand-made humor-oriented lexicons, it is possible to generate puns based on complex phrases. As the output list is often excessively long, we also propose a method for reducing the number of candidates by comparing two web-query-based rankings. The evaluation experiment showed that the system achieved an accuracy of 72.5% for finding proper candidates in general, and the reduction method allowed us to significantly shorten the candidates list. The parameters of the reduction algorithm are variable, so that the balance between the number of candidates and the quality of output can be manipulated according to needs.

  11. Autologous bone marrow Th cells can support multiple myeloma cell proliferation in vitro and in xenografted mice.

    Science.gov (United States)

    Wang, D; Fløisand, Y; Myklebust, C V; Bürgler, S; Parente-Ribes, A; Hofgaard, P O; Bogen, B; Tasken, K; Tjønnfjord, G E; Schjesvold, F; Dalgaard, J; Tveita, A; Munthe, L A

    2017-02-24

    Multiple myeloma (MM) is a plasma cell malignancy where MM cell growth is supported by the bone marrow (BM) microenvironment with poorly defined cellular and molecular mechanisms. MM cells express CD40, a receptor known to activate autocrine secretion of cytokines and elicit proliferation. Activated T helper (Th) cells express CD40 ligand (CD40L) and BM Th cells are significantly increased in MM patients. We hypothesized that activated BM Th cells could support MM cell growth. We here found that activated autologous BM Th cells supported MM cell growth in a contact- and CD40L-dependent manner in vitro. MM cells had retained the ability to activate Th cells that reciprocated and stimulated MM cell proliferation. Autologous BM Th cells supported MM cell growth in xenografted mice and were found in close contact with MM cells. MM cells secreted chemokines that attracted Th cells, secretion was augmented by CD40-stimulation. Within 14 days of culture of whole bone marrow aspirates in autologous serum, MM cells and Th cells mutually stimulated each other, and MM cells required Th cells for further expansion in vitro and in mice. The results suggest that Th cells may support the expansion of MM cells in patients.Leukemia accepted article preview online, 24 February 2017. doi:10.1038/leu.2017.69.

  12. Generation of functional thymic epithelium from human embryonic stem cells that supports host T cell development.

    Science.gov (United States)

    Parent, Audrey V; Russ, Holger A; Khan, Imran S; LaFlam, Taylor N; Metzger, Todd C; Anderson, Mark S; Hebrok, Matthias

    2013-08-01

    Inducing immune tolerance to prevent rejection is a key step toward successful engraftment of stem-cell-derived tissue in a clinical setting. Using human pluripotent stem cells to generate thymic epithelial cells (TECs) capable of supporting T cell development represents a promising approach to reach this goal; however, progress toward generating functional TECs has been limited. Here, we describe a robust in vitro method to direct differentiation of human embryonic stem cells (hESCs) into thymic epithelial progenitors (TEPs) by precise regulation of TGFβ, BMP4, RA, Wnt, Shh, and FGF signaling. The hESC-derived TEPs further mature into functional TECs that support T cell development upon transplantation into thymus-deficient mice. Importantly, the engrafted TEPs produce T cells capable of in vitro proliferation as well as in vivo immune responses. Thus, hESC-derived TEP grafts may have broad applications for enhancing engraftment in cell-based therapies as well as restoring age- and stress-related thymic decline.

  13. Detection of ectopic B-cell follicles with germinal centers in the meninges of patients with secondary progressive multiple sclerosis.

    Science.gov (United States)

    Serafini, Barbara; Rosicarelli, Barbara; Magliozzi, Roberta; Stigliano, Egidio; Aloisi, Francesca

    2004-04-01

    Multiple sclerosis (MS) is characterized by synthesis of oligoclonal immunoglobulins and the presence of B-cell clonal expansions in the central nervous system (CNS). Because ectopic lymphoid tissue generated at sites of chronic inflammation is thought to be important in sustaining immunopathological processes, we have investigated whether structures resembling lymphoid follicles could be identified in the CNS of MS patients. Sections from post-mortem MS brains and spinal cords were screened using immunohistochemistry for the presence of CD20+ B-cells, CD3+ T-cells, CD138+ plasma cells and CD21+, CD35+ follicular dendritic cells, and for the expression of lymphoid chemokines (CXCL 13, CCL21) and peripheral node addressin (PNAd). Lymphoid follicle-like structures containing B-cells, T-cells and plasma cells, and a network of follicular dendritic cells producing CXCL13 were observed in the cerebral meninges of 2 out of 3 patients with secondary progressive MS, but not in relapsing remitting and primary progressive MS. We also show that proliferating B-cells are present in intrameningeal follicles, a finding which is suggestive of germinal center formation. No follicle-like structures were detected in parenchymal lesions. The formation of ectopic lymphoid follicies in the meninges of patients with MS could represent a critical step in maintaining humoral autoimmunity and in disease exacerbation.

  14. Development of Adult-Generated Cell Connectivity with Excitatory and Inhibitory Cell Populations in the Hippocampus.

    Science.gov (United States)

    Restivo, Leonardo; Niibori, Yosuke; Mercaldo, Valentina; Josselyn, Sheena A; Frankland, Paul W

    2015-07-22

    New neurons are generated continuously in the subgranular zone of the hippocampus and integrate into existing hippocampal circuits throughout adulthood. Although the addition of these new neurons may facilitate the formation of new memories, as they integrate, they provide additional excitatory drive to CA3 pyramidal neurons. During development, to maintain homeostasis, new neurons form preferential contacts with local inhibitory circuits. Using retroviral and transgenic approaches to label adult-generated granule cells, we first asked whether a comparable process occurs in the adult hippocampus in mice. Similar to development, we found that, during adulthood, new neurons form connections with inhibitory cells in the dentate gyrus, hilus, and CA3 regions as they integrate into hippocampal circuits. In particular, en passant bouton and filopodia connections with CA3 interneurons peak when adult-generated dentate granule cells (DGCs) are ∼4 weeks of age, a time point when these cells are most excitable. Consistent with this, optical stimulation of 4-week-old (but not 6- or 8-week-old) adult-generated DGCs strongly activated CA3 interneurons. Finally, we found that CA3 interneurons were activated robustly during learning and that their activity was strongly coupled with activity of 4-week-old (but not older) adult-generated DGCs. These data indicate that, as adult-generated neurons integrate into hippocampal circuits, they transiently form strong anatomical, effective, and functional connections with local inhibitory circuits in CA3. Significance statement: New neurons are generated continuously in the subgranular zone of the hippocampus and integrate into existing hippocampal circuits throughout adulthood. Understanding how these cells integrate within well formed circuits will increase our knowledge about the basic principles governing circuit assembly in the adult hippocampus. This study uses a combined connectivity analysis (anatomical, functional, and effective

  15. Enhanced generation of retinal progenitor cells from human retinal pigment epithelial cells induced by amniotic fluid

    Directory of Open Access Journals (Sweden)

    Sanie-Jahromi Fatemeh

    2012-04-01

    Full Text Available Abstract Background Retinal progenitor cells are a convenient source of cell replacement therapy in retinal degenerative disorders. The purpose of this study was to evaluate the expression patterns of the homeobox genes PAX6 and CHX10 (retinal progenitor markers during treatment of human retinal pigment epithelium (RPE cells with amniotic fluid (AF, RPE cells harvested from neonatal cadaver globes were cultured in a mixture of DMEM and Ham's F12 supplemented with 10% FBS. At different passages, cells were trypsinized and co-cultured with 30% AF obtained from normal fetuses of 1416 weeks gestational age. Results Compared to FBS-treated controls, AF-treated cultures exhibited special morphological changes in culture, including appearance of spheroid colonies, improved initial cell adhesion and ordered cell alignment. Cell proliferation assays indicated a remarkable increase in the proliferation rate of RPE cells cultivated in 30% AF-supplemented medium, compared with those grown in the absence of AF. Immunocytochemical analyses exhibited nuclear localization of retinal progenitor markers at a ratio of 33% and 27% for CHX10 and PAX6, respectively. This indicated a 3-fold increase in retinal progenitor markers in AF-treated cultures compared to FBS-treated controls. Real-time PCR data of retinal progenitor genes (PAX6, CHX10 and VSX-1 confirmed these results and demonstrated AF's capacity for promoting retinal progenitor cell generation. Conclusion Taken together, the results suggest that AF significantly promotes the rate of retinal progenitor cell generation, indicating that AF can be used as an enriched supplement for serum-free media used for the in vitro propagation of human progenitor cells.

  16. Myelin repair and functional recovery mediated by neural cell transplantation in a mouse model of multiple sclerosis

    Institute of Scientific and Technical Information of China (English)

    Lianhua Bai; Jordan Hecker; Amber Kerstetter; Robert H.Miller

    2013-01-01

    Cellular therapies are becoming a major focus for the treatment of demyelinating diseases such as multiple sclerosis (MS),therefore it is important to identify the most effective cell types that promote myelin repair.Several components contribute to the relative benefits of specific cell types including the overall efficacy of the cell therapy,the reproducibility of treatment,the mechanisms of action of distinct cell types and the ease of isolation and generation of therapeutic populations.A range of distinct cell populations promote functional recovery in animal models of MS including neural stem cells and mesenchymal stem cells derived from different tissues.Each of these cell populations has advantages and disadvantages and likely works through distinct mechanisms.The relevance of such mechanisms to myelin repair in the adult central nervous system is unclear since the therapeutic cells are generally derived from developing animals.Here we describe the isolation and characterization of a population of neural cells from the adult spinal cord that are characterized by the expression of the cell surface glycoprotein NG2.In functional studies,injection of adult NG2+ cells into mice with ongoing MOG35-55-induced experimental autoimmune encephalomyelitis (EAE) enhanced remyelination in the CNS while the number of CD3+ T cells in areas of spinal cord demyelination was reduced approximately three-fold.In vivo studies indicated that in EAE,NG2+ cells stimulated endogenous repair while in vitro they responded to signals in areas of induced inflammation by differentiating into oligodendrocytes.These results suggested that adult NG2+ cells represent a useful cell population for promoting neural repair in a variety of different conditions including demyelinating diseases such as MS.

  17. Busulfan,cyclophosphamide and etoposide as conditioning for autologous stem cell transplantation in multiple myeloma

    Institute of Scientific and Technical Information of China (English)

    张春阳

    2013-01-01

    Objective To evaluate the efficacy and safety of dose-reduced intravenous busulfan,cyclophosphamide and etoposide(BCV)as conditioning for autologous stem cell transplantation(ASCT)in multiple myeloma(MM)

  18. Treatment Option Overview (Plasma Cell Neoplasms Including Multiple Myeloma)

    Science.gov (United States)

    ... chromosomes . Other tests, such as fluorescence in situ hybridization (FISH) and flow cytometry , may also be done ... sample made up of red blood cells. Blood chemistry studies : A procedure in which a blood sample ...

  19. Treatment Options for Plasma Cell Neoplasms (Including Multiple Myeloma)

    Science.gov (United States)

    ... chromosomes . Other tests, such as fluorescence in situ hybridization (FISH) and flow cytometry , may also be done ... sample made up of red blood cells. Blood chemistry studies : A procedure in which a blood sample ...

  20. General Information about Plasma Cell Neoplasms (Including Multiple Myeloma)

    Science.gov (United States)

    ... chromosomes . Other tests, such as fluorescence in situ hybridization (FISH) and flow cytometry , may also be done ... sample made up of red blood cells. Blood chemistry studies : A procedure in which a blood sample ...

  1. The optimizations of CGH generation algorithms based on multiple GPUs for 3D dynamic holographic display

    Science.gov (United States)

    Yang, Dan; Liu, Juan; Zhang, Yingxi; Li, Xin; Wang, Yongtian

    2016-10-01

    Holographic display has been considered as a promising display technology. Currently, low-speed generation of holograms with big holographic data is one of crucial bottlenecks for three dimensional (3D) dynamic holographic display. To solve this problem, the acceleration method computation platform is presented based on look-up table point source method. The computer generated holograms (CGHs) acquisition is sped up by offline file loading and inline calculation optimization, where a pure phase CGH with gigabyte data is encoded to record an object with 10 MB sampling data. Both numerical simulation and optical experiment demonstrate that the CGHs with 1920×1080 resolution by the proposed method can be applied to the 3D objects reconstruction with high quality successfully. It is believed that the CGHs with huge data can be generated by the proposed method with high speed for 3D dynamic holographic display in near future.

  2. Generation of embryonic stem cells from mouse adipose-tissue derived cells via somatic cell nuclear transfer.

    Science.gov (United States)

    Qin, Yiren; Qin, Jilong; Zhou, Chikai; Li, Jinsong; Gao, Wei-Qiang

    2015-01-01

    Somatic cells can be reprogrammed into embryonic stem cells (ESCs) by nuclear transfer (NT-ESCs), or into induced pluripotent stem cells (iPSCs) by the "Yamanaka method." However, recent studies have indicated that mouse and human iPSCs are prone to epigenetic and transcriptional aberrations, and that NT-ESCs correspond more closely to ESCs derived from in vitro fertilized embryos than iPSCs. In addition, the procedure of NT-ESCs does not involve gene modification. Demonstration of generation of NT-ESCs using an easily-accessible source of adult cell types would be very important. Adipose tissue is a source of readily accessible donor cells and can be isolated from both males and females at different ages. Here we report that NT-ESCs can be generated from adipose tissue-derived cells (ADCs). At morphological, mRNA and protein levels, these NT-ESCs show classic ESC colonies, exhibit alkaline phosphatase (AP) activity, and display normal diploid karyotypes. Importantly, these cells express pluripotent markers including Oct4, Sox2, Nanog and SSEA-1. Furthermore, they can differentiate in vivo into various types of cells from 3 germinal layers by teratoma formation assays. This study demonstrates for the first time that ESCs can be generated from the adipose tissue by somatic cell nuclear transfer (SCNT) and suggests that ADCs can be a new donor-cell type for potential therapeutic cloning.

  3. Compost in plant microbial fuel cell for bioelectricity generation.

    Science.gov (United States)

    Moqsud, M A; Yoshitake, J; Bushra, Q S; Hyodo, M; Omine, K; Strik, David

    2015-02-01

    Recycling of organic waste is an important topic in developing countries as well as developed countries. Compost from organic waste has been used for soil conditioner. In this study, an experiment has been carried out to produce green energy (bioelectricity) by using paddy plant microbial fuel cells (PMFCs) in soil mixed with compost. A total of six buckets filled with the same soil were used with carbon fiber as the electrodes for the test. Rice plants were planted in five of the buckets, with the sixth bucket containing only soil and an external resistance of 100 ohm was used for all cases. It was observed that the cells with rice plants and compost showed higher values of voltage and power density with time. The highest value of voltage showed around 700 mV when a rice plant with 1% compost mixed soil was used, however it was more than 95% less in the case of no rice plant and without compost. Comparing cases with and without compost but with the same number of rice plants, cases with compost depicted higher voltage to as much as 2 times. The power density was also 3 times higher when the compost was used in the paddy PMFCs which indicated the influence of compost on bio-electricity generation.

  4. Generating kidney organoids from human pluripotent stem cells

    Science.gov (United States)

    Takasato, Minoru; Er, Pei X; Chiu, Han S; Little, Melissa H

    2016-01-01

    The human kidney develops from four progenitor populations; nephron progenitors, ureteric epithelial progenitors, renal interstitial progenitors and endothelial progenitors; resulting in the formation of maximally 2 million nephrons. Until recently, methods differentiating human pluripotent stem cells (hPSCs) into either nephron progenitor or ureteric epithelial progenitor had been reported, consequently forming only nephrons or collecting ducts, respectively. Here, we detail a protocol that simultaneously induces all four progenitors to generate kidney organoids within which segmented nephrons are connected to collecting ducts and surrounded by renal interstitial cells and an endothelial network. As evidence of functional maturity, proximal tubules within organoids display megalin-mediated and cubilin-mediated endocytosis, and respond to a nephrotoxicant to undergo apoptosis. This protocol consists of 7 days of monolayer culture for intermediate mesoderm induction followed by 18 days of three-dimensional culture to facilitate self-organising renogenic events leading to organoid formation. Personnel experienced in culturing hPSCs are required to conduct this protocol. PMID:27560173

  5. Identification of Suitable Reference Genes for Peripheral Blood Mononuclear Cell Subset Studies in Multiple Sclerosis

    DEFF Research Database (Denmark)

    Oturai, D B; Søndergaard, H B; Börnsen, L;

    2016-01-01

    Quantitative real-time PCR (qPCR) involves the need of a proper standard for normalizing the gene expression data. Different studies have shown the validity of reference genes to vary greatly depending on tissue, cell subsets and experimental context. This study aimed at the identification...... of suitable reference genes for qPCR studies using different peripheral blood cell subsets (whole blood (WB) cells, peripheral blood mononuclear cells (PBMCs) and PBMC subsets (CD4(+) T cells, CD8(+) T cells, NK cells, monocytes, B cells and dendritic cells) from healthy controls (HC), patients with relapsing...... stable combination for analyses of cell subsets between HC and RRMS patients, while the combination of UBC and YWHAZ was superior for analysis of cell subsets between HC, RRMS and RRMS-IFN-β groups. GAPDH was generally unsuitable for blood cell subset studies in multiple sclerosis. In conclusion, we...

  6. The Correlation Function of Multiple Dependent Poisson Processes Generated by the Alternating Renewal Process Method

    CERN Document Server

    Johnson, Don H

    2008-01-01

    We derive conditions under which alternating renewal processes can be used to construct correlated Poisson processes. The pairwise correlation function is also derived, showing that the resulting correlations can be negative. The technique and the analysis can be extended to the generation of two or more dependent renewal processes.

  7. Th17 Cells Pathways in Multiple Sclerosis and Neuromyelitis Optica Spectrum Disorders: Pathophysiological and Therapeutic Implications

    OpenAIRE

    Giordani Rodrigues Dos Passos; Douglas Kazutoshi Sato; Jefferson Becker; Kazuo Fujihara

    2016-01-01

    Several animal and human studies have implicated CD4+ T helper 17 (Th17) cells and their downstream pathways in the pathogenesis of central nervous system (CNS) autoimmunity in multiple sclerosis (MS) and neuromyelitis optica spectrum disorders (NMOSD), challenging the traditional Th1-Th2 paradigm. Th17 cells can efficiently cross the blood-brain barrier using alternate ways from Th1 cells, promote its disruption, and induce the activation of other inflammatory cells in the CNS. A number of e...

  8. Generation of Tolerogenic Dendritic Cells for Cell Therapy in Multiple Sclerosis

    OpenAIRE

    Raïch Regué, Dàlia

    2012-01-01

    L'esclerosi múltiple (EM) és considerada una malaltia autoimmune crònica que afecta el sistema nerviós central. Els tractaments actuals pels pacients amb EM remitent-recurrent (EM-RR) redueixen la freqüència dels brots i l'activitat inflamatòria general, però el seu efecte en la progressió de la malaltia encara no està clar. Per això és necessari desenvolupar noves aproximacions terapèutiques més específiques per tal de modificar el curs de la malaltia. En aquest sentit, una estratègia terapè...

  9. The multiple connections between pRB and cell metabolism.

    Science.gov (United States)

    Nicolay, Brandon N; Dyson, Nicholas J

    2013-12-01

    The pRB tumor suppressor is traditionally seen as an important regulator of the cell cycle. pRB represses the transcriptional activation of a diverse set of genes by the E2F transcription factors and prevents inappropriate S-phase entry. Advances in our understanding of pRB have documented roles that extend beyond the cell cycle and this review summarizes recent studies that link pRB to the control of cell metabolism. pRB has been shown to regulate glucose tolerance, mitogenesis, glutathione synthesis, and the expression of genes involved in central carbon metabolism. Several studies have demonstrated that pRB directly targets a set of genes that are crucial for nucleotide metabolism, and this seems likely to represent one of the ways by which pRB influences the G1/S-phase transition and S-phase progression.

  10. Oval cells and cystic structures in multiplication of M leprae

    Directory of Open Access Journals (Sweden)

    Bhatia V

    1995-01-01

    Full Text Available Ten preserved biopsy suspensions from leprosy patients were inoculated in biphasic medium and incubated alternatively in refrigerator and at 37 °C. The cultures were observed every week for 3 months. The typical actinomycetoid growth appeared within 3-5 days. Microscopically, two types of cysts (unstained and dark were seen along with oval cells. Dark cysts showed developement of irregular septae or cracks breaking the mass into irregular quadrangular pieces. Granular acid-fast material could be made out inside the cracks and around the cysts. Oval cells were seen either independently or organised around pink homogeneous material. The oval cells were stained blue or pink. Some of them showed both blue and pink shades.

  11. Tolerogenic Dendritic Cells Generated by In Vitro Treatment With SAHA Are Not Stable In Vivo.

    Science.gov (United States)

    Thewissen, Kristof; Broux, Bieke; Hendriks, Jerome J A; Vanhees, Mandy; Stinissen, Piet; Slaets, Helena; Hellings, Niels

    2016-01-01

    The aim of this study is to examine whether the histone deacetylase inhibitor, suberoylanilide hydroxamic acid (SAHA), can generate dendritic cells (DCs) with a stable tolerogenic phenotype to counteract autoimmune responses in an animal model of multiple sclerosis. We investigated if the tolerogenic potency of DCs could be increased by continuous treatment during in vitro differentiation toward DCs compared to standard 24-h in vitro treatment of already terminally differentiated DCs. We show that in vitro treatment with SAHA reduces the generation of new CD11c(+) DCs out of mouse bone marrow. SAHA-generated DCs show reduced antigen-presenting function as evidenced by a reduction in myelin endocytosis, a decreased MHC II expression, and a failure to upregulate costimulatory molecules upon LPS challenge. In addition, SAHA-generated DCs display a reduction in proinflammatory cytokines and molecules involved in apoptosis induction, inflammatory migration, and TLR signaling, and they are less immunostimulatory compared to untreated DCs. We demonstrated that the underlying mechanism involves a diminished STAT1 phosphorylation and was independent of STAT6 activation. Although in vitro results were promising, SAHA-generated DCs were not able to alleviate the development of experimental autoimmune encephalomyelitis in mice. In vitro washout experiments demonstrated that the tolerogenic phenotype of SAHA-treated DCs is reversible. Taken together, while SAHA potently boosts tolerogenic properties in DCs during the differentiation process in vitro, SAHA-generated DCs were unable to reduce autoimmunity in vivo. Our results imply that caution needs to be taken when developing DC-based therapies to induce tolerance in the context of autoimmune disease.

  12. Generation of red blood cells from human embryonic/induced pluripotent stem cells for blood transfusion.

    Science.gov (United States)

    Ebihara, Yasuhiro; Ma, Feng; Tsuji, Kohichiro

    2012-06-01

    Red blood cell (RBC) transfusion is necessary for many patients with emergency or hematological disorders. However, to date the supply of RBCs remains labile and dependent on voluntary donations. In addition, the transmission of infectious disease via blood transfusion from unspecified donors remains a risk. Establishing a large quantity of safe RBCs would help to address this issue. Human embryonic stem (hES) cells and the recently established human induced pluripotent stem (hiPS) cells represent potentially unlimited sources of donor-free RBCs for blood transfusion, as they can proliferate indefinitely in vitro. Extensive research has been done to efficiently generate transfusable RBCs from hES/iPS cells. Nevertheless, a number of challenges must be overcome before the clinical usage of hES/iPS cell-derived RBCs can become a reality.

  13. Gas dilution system using critical flow Venturi nozzles for generating primary trace-moisture standards in multiple gas species

    Science.gov (United States)

    Amano, Minami; Abe, Hisashi

    2017-02-01

    Gas dilution systems are commonly used to generate calibration gas mixtures for secondary gas standards. However, if a gas dilution system is used to generate gas mixtures for primary trace-moisture standards in multiple gas species, difficulty arises; flow control with relative stability of better than 0.009% is required although the relative uncertainty of the best gas flow meter to date is around 0.3%. In this study, we developed a novel gas dilution system using critical flow Venturi nozzles to address this problem. The developed dilution system can measure and control the flow rates of gases in the range of approximately 0.05 l min-1 to 7 l min-1 (when converted to those measured at 101 325 Pa and 273.15 K) with relative stability of better than 0.007%. Using the dilution system, we developed a magnetic suspension balance/diffusion-tube humidity generator capable of generating trace moisture in N2 in the range of approximately 10 nmol mol-1 to 5 µmol mol-1 in amount fraction. The accuracy of the generated trace-moisture standard was verified by measurement with cavity ring-down spectroscopy.

  14. Multiple-cylindrical Electrode System for Rotational Electric Field Generation in Particle Rotation Applications

    Directory of Open Access Journals (Sweden)

    Prateek Benhal

    2015-07-01

    Full Text Available Lab-on-a-chip micro-devices utilizing electric field-mediated particle movement provide advantages over current cell rotation techniques due to the flexibility in configuring micro-electrodes. Recent technological advances in micro-milling, three-dimensional (3D printing and photolithography have facilitated fabrication of complex micro-electrode shapes. Using the finite-element method to simulate and optimize electric field induced particle movement systems can save time and cost by simplifying the analysis of electric fields within complex 3D structures. Here we investigated different 3D electrode structures to obtain and analyse rotational electric field vectors. Finite-element analysis was conducted by an electric current stationary solver based on charge relaxation theory. High-resolution data were obtained for three-, four-, six- and eight-cylindrical electrode arrangements to characterize the rotational fields. The results show that increasing the number of electrodes within a fixed circular boundary provides larger regions of constant amplitude rotational electric field. This is a very important finding in practice, as larger rotational regions with constant electric field amplitude make placement of cells into these regions, where cell rotation occurs, a simple task – enhancing flexibility in cell manipulation. Rotation of biological particles over the extended region would be useful for biotechnology applications which require guiding cells to a desired location, such as automation of nuclear transfer cloning.

  15. Multiple Modes of Communication between Neurons and Oligodendrocyte Precursor Cells

    NARCIS (Netherlands)

    Maldonado, Paloma P; Angulo, María Cecilia

    2015-01-01

    The surprising discovery of bona fide synapses between neurons and oligodendrocytes precursor cells (OPCs) 15 years ago placed these progenitors as real partners of neurons in the CNS. The role of these synapses has not been established yet, but a main hypothesis is that neuron-OPC synaptic activity

  16. Stem Cell Transplants May Help Some with Multiple Sclerosis

    Science.gov (United States)

    ... for MS. However, it can be considered a concrete option for patients showing aggressive MS who have not responded to approved treatments," said study co-author Dr. Riccardo Saccardi. He's from the cell therapy and transfusion medicine unit at Careggi University ...

  17. Generation of broadband and multiple-peak THz radiation in aperiodically poled lithium niobate

    Institute of Scientific and Technical Information of China (English)

    Fucheng Chen; Xianfeng Chen; Yuping Chen; Yuxing Xia

    2005-01-01

    @@ We theoretically analyze the generation of broadened and multi-peak terahertz (THz) radiation in aperiodically poled lithium niobate (APPLN), whose sequence of opposite domains is optimized by simulated annealing (SA) algorithm. The full-width at half maximum (FWHM) of the broadened THz radiation in our simulation is 0.26 THz. Both of the central wavelength and FWHM can be easily tuned by choosing proper objective functions. THz radiation with wider and flatter FWHM can be achieved by increasing the length of the lithium niobate crystal. The two-peak THz generation is also provided as an example of multi-peak with the central wavelengths at 1.68 and 1.80 THz, respectively.

  18. Intracranial Tumor Cell Migration and the Development of Multiple Brain Metastases in Malignant Melanoma

    Directory of Open Access Journals (Sweden)

    Trude G. Simonsen

    2016-06-01

    Full Text Available INTRODUCTION: A majority of patients with melanoma brain metastases develop multiple lesions, and these patients show particularly poor prognosis. To develop improved treatment strategies, detailed insights into the biology of melanoma brain metastases, and particularly the development of multiple lesions, are needed. The purpose of this preclinical investigation was to study melanoma cell migration within the brain after cell injection into a well-defined intracerebral site. METHODS: A-07, D-12, R-18, and U-25 human melanoma cells transfected with green fluorescent protein were injected stereotactically into the right cerebral hemisphere of nude mice. Moribund mice were killed and autopsied, and the brain was evaluated by fluorescence imaging or histological examination. RESULTS: Intracerebral inoculation of melanoma cells produced multiple lesions involving all regions of the brain, suggesting that the cells were able to migrate over substantial distances within the brain. Multiple modes of transport were identified, and all transport modes were observed in all four melanoma lines. Thus, the melanoma cells were passively transported via the flow of cerebrospinal fluid in the meninges and ventricles, they migrated actively along leptomeningeal and brain parenchymal blood vessels, and they migrated actively along the surfaces separating different brain compartments. CONCLUSION: Migration of melanoma cells after initial arrest, extravasation, and growth at a single location within the brain may contribute significantly to the development of multiple melanoma brain metastases.

  19. Automatic selection of informative sentences: The sentences that can generate multiple choice questions

    Directory of Open Access Journals (Sweden)

    Mukta Majumder

    2014-12-01

    Full Text Available Traditional education cannot meet the expectation and requirement of a Smart City; it require more advance forms like active learning, ICT education etc. Multiple choice questions (MCQs play an important role in educational assessment and active learning which has a key role in Smart City education. MCQs are effective to assess the understanding of well-defined concepts. A fraction of all the sentences of a text contain well-defined concepts or information that can be asked as a MCQ. These informative sentences are required to be identified first for preparing multiple choice questions manually or automatically. In this paper we propose a technique for automatic identification of such informative sentences that can act as the basis of MCQ. The technique is based on parse structure similarity. A reference set of parse structures is compiled with the help of existing MCQs. The parse structure of a new sentence is compared with the reference structures and if similarity is found then the sentence is considered as a potential candidate. Next a rule-based post-processing module works on these potential candidates to select the final set of informative sentences. The proposed approach is tested in sports domain, where many MCQs are easily available for preparing the reference set of structures. The quality of the system selected sentences is evaluated manually. The experimental result shows that the proposed technique is quite promising.

  20. An aluminium tool for multiple stellar generations in the globular clusters 47 Tuc and M 4

    CERN Document Server

    Carretta, Eugenio; Bragaglia, Angela; D'Orazi, Valentina; Lucatello, Sara

    2012-01-01

    We present aluminium abundances for a sample of about 100 red giant stars in each of the Galactic globular clusters 47 Tuc (NGC 104) and M 4 (NGC 6121). We have derived homogeneous abundances from intermediate-resolution FLAMES/GIRAFFE spectra. Aluminium abundances are from the strong doublet Al I at 8772-8773 A as in previous works done for giants in NGC 6752 and NGC 1851, and nitrogen abundances are extracted from a large number of features of the CN molecules, by assuming a suitable carbon abundance. We added previous homogeneous abundances of O and Na and newly derived abundances of Mg and Si for our samples of 83 stars in M 4 and 116 stars in 47 Tuc to obtain the full set of elements from proton-capture reactions produced by different stellar generations in these clusters. By simultaneously studying the Ne-Na and Mg-Al cycles of H-burning at high temperature our main aims are to understand the nature of the polluters at work in the first generation and to ascertain whether the second generation of cluste...

  1. Generating anagrams from multiple core strings employing user-defined vocabularies and orthographic parameters.

    Science.gov (United States)

    Jordan, Timothy R; Monteiro, Axel

    2003-02-01

    Anagrams are used widely in psychological research. However, generating a range of strings with the same letter content is an inherently difficult and time-consuming task for humans, and current computer-based anagram generators do not provide the controls necessary for psychological research. In this article, we present a computational algorithm that overcomes these problems. Specifically, the algorithm processes automatically each word in a user-defined source vocabulary and outputs, for each word, all possible anagrams that exist as words (or as nonwords, if required) as defined by the same source vocabulary. Moreover, we show how the output of the algorithm can be filtered to produce anagrams within specific user-defined orthographic parameters. For example, the anagrams produced can be filtered to produce words that share, with each other or with other words in the source vocabulary, letters in only certain positions. Finally, we provide free access to the complete Windows-based program and source code containing these facilities for anagram generation.

  2. KSR-Based Medium Improves the Generation of High-Quality Mouse iPS Cells

    OpenAIRE

    2014-01-01

    Induced pluripotent stem (iPS) cells from somatic cells have great potential for regenerative medicine. The efficiency in generation of iPS cells has been significantly improved in recent years. However, the generation of high-quality iPS cells remains of high interest. Consistently, we demonstrate that knockout serum replacement (KSR)-based medium accelerates iPS cell induction and improves the quality of iPS cells, as confirmed by generation of chimeras and all iPS cell-derived offspring wi...

  3. GiMMiK-Generating bespoke matrix multiplication kernels for accelerators: Application to high-order Computational Fluid Dynamics

    Science.gov (United States)

    Wozniak, Bartosz D.; Witherden, Freddie D.; Russell, Francis P.; Vincent, Peter E.; Kelly, Paul H. J.

    2016-05-01

    Matrix multiplication is a fundamental linear algebra routine ubiquitous in all areas of science and engineering. Highly optimised BLAS libraries (cuBLAS and clBLAS on GPUs) are the most popular choices for an implementation of the General Matrix Multiply (GEMM) in software. In this paper we present GiMMiK-a generator of bespoke matrix multiplication kernels for the CUDA and OpenCL platforms. GiMMiK exploits a prior knowledge of the operator matrix to generate highly performant code. The performance of GiMMiK's kernels is particularly apparent in a block-by-panel type of matrix multiplication, where the block matrix is typically small (e.g. dimensions of 96 × 64). Such operations are characteristic to our motivating application in PyFR-an implementation of Flux Reconstruction schemes for high-order fluid flow simulations on mixed unstructured meshes. GiMMiK fully unrolls the matrix-vector product and embeds matrix entries directly in the code to benefit from the use of the constant cache and compiler optimisations. Further, it reduces the number of floating-point operations by removing multiplications by zeros. Together with the ability of our kernels to avoid the poorly optimised cleanup code, executed by library GEMM, we are able to outperform cuBLAS on two NVIDIA GPUs: GTX 780 Ti and Tesla K40c. We observe speedups of our kernels over cuBLAS GEMM of up to 9.98 and 63.30 times for a 294×1029 99% sparse PyFR matrix in double precision on the Tesla K40c and GTX 780 Ti correspondingly. In single precision, observed speedups reach 12.20 and 13.07 times for a 4×8 50% sparse PyFR matrix on the two aforementioned cards. Using GiMMiK as the matrix multiplication kernel provider allows us to achieve a speedup of up to 1.70 (2.19) for a simulation of an unsteady flow over a cylinder executed with PyFR in double (single) precision on the Tesla K40c. All results were generated with GiMMiK version 1.0.

  4. Circulating clonotypic B cells in multiple myeloma and monoclonal gammopathy of undetermined significance.

    Science.gov (United States)

    Thiago, Leandro S; Perez-Andres, Martin; Balanzategui, Ana; Sarasquete, Maria E; Paiva, Bruno; Jara-Acevedo, Maria; Barcena, Paloma; Sanchez, Maria Luz; Almeida, Julia; González, Marcos; San Miguel, Jesus F; Garcia-Sanz, Ramón; Orfao, Alberto

    2014-01-01

    The B-cell compartment in which multiple myeloma stem cells reside remains unclear. We investigated the potential presence of mature, surface-membrane immunoglobulin-positive B lymphocytes clonally related to the tumor bone marrow plasma cells among different subsets of peripheral blood B cells from ten patients (7 with multiple myeloma and 3 with monoclonal gammopathies of undetermined significance). The presence of clonotypic immunoglobulin heavy chain gene rearrangements was determined in multiple highly-purified fractions of peripheral blood B-lymphocytes including surface-membrane IgM(+) CD27(-) naïve B-lymphocytes, plus surface-membrane IgG(+), IgA(+) and IgM(+) memory CD27(+) B cells, and normal circulating plasma cells, in addition to (mono)clonal plasma cells, by a highly-specific and sensitive allele-specific oligonucleotide polymerase chain reaction directed to the CDR3 sequence of the rearranged IGH gene of tumor plasma cells from individual patients. Our results showed systematic absence of clonotypic rearrangements in all the different B-cell subsets analyzed, including M-component isotype-matched memory B-lymphocytes, at frequencies undetermined significance are usually devoid of clonotypic B cells while the presence of immunophenotypically aberrant myeloma plasma cells in peripheral blood of myeloma patients is a relatively frequent finding.

  5. Effects of Armature Winding Segmentation with Multiple Converters on the Short Circuit Torque of 10-MW Superconducting Wind Turbine Generators

    DEFF Research Database (Denmark)

    Liu, Dong; Polinder, Henk; Abrahamsen, Asger Bech;

    2017-01-01

    Superconducting synchronous generators (SCSGs) are drawing more attention in large direct-drive wind turbine applications. Despite low weight and compactness, the short circuit torque of an SCSG may be too high for wind turbine constructions due to a large magnetic air gap of an SCSG. This paper...... aims at assessing the effects of armature winding segmentation on reducing the short circuit torque of 10-MW SCSGs. A concept of armature winding segmentation with multiple power electronic converters is presented. Four SCSG designs using different topologies are examined. Results show that armature...

  6. Efficient Multiple Exciton Generation Observed in Colloidal PbSe Quantum Dots with Temporally and Spectrally Resolved Intraband Excitation

    KAUST Repository

    Ji, Minbiao

    2009-03-11

    We have spectrally resolved the intraband transient absorption of photogenerated excitons to quantify the exciton population dynamics in colloidal PbSe quantum dots (QDs). These measurements demonstrate that the spectral distribution, as well as the amplitude, of the transient spectrum depends on the number of excitons excited in a QD. To accurately quantify the average number of excitons per QD, the transient spectrum must be spectrally integrated. With spectral integration, we observe efficient multiple exciton generation In colloidal PbSe QDs. © 2009 American Chemical Society.

  7. Incorporating Environmental Justice into Second Generation Indices of Multiple Deprivation: Lessons from the UK and Progress Internationally

    Directory of Open Access Journals (Sweden)

    Jon Fairburn

    2016-07-01

    Full Text Available Second generation area-based indices of multiple deprivation have been extensively used in the UK over the last 15 years. They resulted from significant developments in political, technical, and conceptual spheres for deprivation data. We review the parallel development of environmental justice research and how and when environmental data was incorporated into these indices. We explain the transfer of these methods from the UK to Germany and assess the progress internationally in developing such indices. Finally, we illustrate how billions of pounds in the UK was allocated by using these tools to tackle neighbourhood deprivation and environmental justice to address the determinants of health.

  8. Geometric ortho-rectification and generation of sigma(0) image products from multiple incidence synthetic aperture radar images

    Science.gov (United States)

    Curlander, James; Leberl, Franz; Kruse, Fred

    1992-01-01

    The results of the first phase of a cooperative effort in geometric orthorectification and generation of sigma(0) images of multiple incidence SAR images are presented. The geometric accuracy of the final image products is approximately 18 m or 1.5 pixels. A method for registering radar imagery collected from an airborne platform to an existing digital elevation model despite the effects of unmodeled variations in the flight path of the platform is demonstrated. The results indicate the requirements for a more detailed digital elevation model.

  9. Autophagy counteracts apoptosis in human multiple myeloma cells exposed to oridonin in vitro via regulating intracellular ROS and SIRT1

    Institute of Scientific and Technical Information of China (English)

    Rong ZENG; Yan CHEN; Shuai ZHAO; Guo-hui CUI

    2012-01-01

    To explore the mechanisms underlying the oridonin-induced apoptosis and autophagy in human multiple myeloma cells in vitro.Methods:Human multiple myeloma RPMI8266 cells were used.The cell viability was assessed using MTT assay.Morphological changes of apoptosis and autophagy were observed under transmission electron microscope.TUNEL and annexin V-FITC/PI dual staining assays were used to measure apoptosis.Autophagy was analyzed using Western blot analysis and immunofluorescence staining with a QDs605 nm-Anti-LC3 fluorescent probe.Intracellular ROS was estimated with flow cytometry using DCFH-DA fluorescent probe.Protein levels of active caspase 3,Beclin 1 and SIRT1 were determined with Western blot analysis.Results:Exposure to oridonin (1-64 μmol/L) inhibited the proliferation of RPMI8266 cells in a concentration-dependent manner with an IC50 value of 6.74 μmol/L.Exposure to oridonin (7 μmol/L) simultaneously induced caspase 3-mediated apoptosis and Beclin 1-dependent autophagy of RPMI8266 cells.Both the apoptosis and autophagy were time-dependent,and apoptosis was the main effector pathway of cell death.Exposure to oridonin (7 μmol/L) increased intracellular ROS and reduced SIRT1 nuclear protein in a time-dependent manner.The blockade of intracellular generation of ROS by NAC (5 mmol/L) abrogated apoptosis,autophagy and the decrease of SIRT1 in the cells exposed to oridonin (7 μmol/L).The inhibition of autophagy by 3-MA (5 mmol/L) sensitized the cells to oridonin-induced apoptosis,which was accompanied by increased intracellular ROS and decreased SlRT1.Conclusion:Oridonin simultaneously induces apoptosis and autophagy of human multiple myeloma RPMI8266 cells via regulation of intracellular ROS generation and SIRT1 nuclear protein.The cytotoxicity of oridonin is mainly mediated through the apoptotic pathway,whereas the autophagy protects the cells from apoptosis.

  10. Mouse Leydig cells express multiple P2X receptor subunits

    OpenAIRE

    2008-01-01

    ATP acts on cellular membranes by interacting with P2X (ionotropic) and P2Y (metabotropic) receptors. Seven homomeric P2X receptors (P2X1–P2X7) and seven heteromeric receptors (P2X1/2, P2X1/4, P2X1/5, P2X2/3, P2X2/6, P2X4/6, P2X4/7) have been described. ATP treatment of Leydig cells leads to an increase in [Ca2+]i and testosterone secretion, supporting the hypothesis that Ca2+ signaling through purinergic receptors contributes to the process of testosterone secretion in these cells. Mouse Ley...

  11. Multiple Knudsen Cell Configuration Improved for Alloy Activity Studies

    Science.gov (United States)

    Copland, Evan H.; Jacobson, Nathan S.

    2003-01-01

    Knudsen effusion mass spectrometry (KEMS) allows the simultaneous determination of the identity and pressure of vapor species in equilibrium with a condensed phase as a function of temperature. This information can be used to determine the thermodynamic properties of materials. The partial pressure of species j in the cell is related to the measured intensity of the ion k formed from j, I(sup +) less than SABjk, and the absolute temperature T, where S(sub jk) is the sensitivity factor.

  12. MULTIPLE EXCITON GENERATIONSOLAR CELLS USING CdSe QUANTUM DOTS

    Directory of Open Access Journals (Sweden)

    HAFTOM MESFIN GEBRESLASSIE,

    2011-03-01

    Full Text Available Experimental and Simulation works of Nano structured Solar Cells Using CdSe Quantum Dots have been analyzed and investigated. CdSe quantum dots have been synthesized from non coordinating and highboiling solvent Octadecene and a series of increasing CdSe particle sizes are produced. The synthesized CdSe quantum dots are highly examined under a Transmission Electron Microscope and four images ofdifferent sizes of CdSe quantum dots (5.8 nm, 6.4 nm, 7.0 nm and 7.7 nm have been obtained. A 1.1x1.1cm2 TiO2 electrode is prepared using indium tin oxide conducting glass and TiO2 nanoparticles. The CdSe quantum dot (5.8nm was adsorbed on TiO2 photoelectrode and used as sensitizer. In this paper work, a sandwich type cell configuration which is made up of TiO2 photoelectrode, graphite coated counter electrode, an electrolyte of iodine and potassium iodide have been used. This sandwich type cell has been exposed to sun light and we have achieved 0.32 V and 0.2 mA

  13. Measurement of nonlinear refractive index based on multiple configuration of FBG in generating multi wavelength

    Science.gov (United States)

    Abdullah, Mohd Nizam; Shaari, Sahbudin; Ehsan, Abang Annuar; Menon, Susthitha; Zakaria, Osman

    2015-06-01

    A reliable method for measurement of the nonlinear refractive index through application of multi wavelength phenomenon. Multi wavelength realisation based on Erbium doped fibre laser (EDFL) is proposed and experimentally demonstrated. A combination of 15 m high efficiency Erbium doped fibre (EDF) and a 20 m Photonic Crystal Fibre (PCF) as main catalyst to suppress the homogenous broadening of EDF and to obtain highly stability of multi wavelength through insertion of a set of fibre Bragg gratings (FBGs) in the cavity. This PCF has zero dispersion of 1040 nm which mismatch from transmission window of 1550 nm. A reliable repeatability of multi wavelength based on multiple configuration of FBGs less than 0.2% obtained. This consistent results influence in determination of nonlinear refractive index by relation of four wave mixing (FWM).

  14. Fast, scalable generation of high-quality protein multiple sequence alignments using Clustal Omega.

    Science.gov (United States)

    Sievers, Fabian; Wilm, Andreas; Dineen, David; Gibson, Toby J; Karplus, Kevin; Li, Weizhong; Lopez, Rodrigo; McWilliam, Hamish; Remmert, Michael; Söding, Johannes; Thompson, Julie D; Higgins, Desmond G

    2011-10-11

    Multiple sequence alignments are fundamental to many sequence analysis methods. Most alignments are computed using the progressive alignment heuristic. These methods are starting to become a bottleneck in some analysis pipelines when faced with data sets of the size of many thousands of sequences. Some methods allow computation of larger data sets while sacrificing quality, and others produce high-quality alignments, but scale badly with the number of sequences. In this paper, we describe a new program called Clustal Omega, which can align virtually any number of protein sequences quickly and that delivers accurate alignments. The accuracy of the package on smaller test cases is similar to that of the high-quality aligners. On larger data sets, Clustal Omega outperforms other packages in terms of execution time and quality. Clustal Omega also has powerful features for adding sequences to and exploiting information in existing alignments, making use of the vast amount of precomputed information in public databases like Pfam.

  15. Simultaneous measurement of membrane potential changes in multiple pattern generating neurons using voltage sensitive dye imaging.

    Science.gov (United States)

    Städele, Carola; Andras, Peter; Stein, Wolfgang

    2012-01-15

    Optical imaging using voltage-sensitive dyes (VSDs) is a promising technique for the simultaneous activity recording of many individual neurons. While such simultaneous recordings are critical for the understanding of the integral functionality of neural systems, functional interpretations on a single neuron level are difficult without knowledge of the connectivity of the underlying circuit. Central pattern generating circuits, such as the pyloric and gastric mill circuits in the stomatogastric ganglion (STG) of crustaceans, allow such investigations due to their well-known connectivities and have already contributed much to our understanding of general neuronal mechanisms. Here we present for the first time simultaneous optical recordings of the pattern generating neurons in the STG of two crustacean species using bulk loading of the VSD di-4-ANEPPS. We demonstrate the recording of firing activities and synaptic interactions of the circuit neurons as well as inter-circuit interactions in their functional context, i.e. without artificial stimulation. Neurons could be uniquely identified using simple event-triggered averaging. We tested this technique in two different species of crustaceans (lobsters and crabs), since several crustacean species are used for studying motor pattern generation. The signal-to-noise ratio of the optical signal was high enough in both species to derive phase-relationship between the network neurons, as well as action potentials and excitatory and inhibitory postsynaptic potentials. We argue that imaging of neural networks with identifiable neurons with well-known connectivity, like in the STG, is crucial for the understanding of emergence of network functionality.

  16. Advanced feeder-free generation of induced pluripotent stem cells directly from blood cells.

    Science.gov (United States)

    Trokovic, Ras; Weltner, Jere; Nishimura, Ken; Ohtaka, Manami; Nakanishi, Mahito; Salomaa, Veikko; Jalanko, Anu; Otonkoski, Timo; Kyttälä, Aija

    2014-12-01

    Generation of validated human induced pluripotent stem cells (iPSCs) for biobanking is essential for exploring the full potential of iPSCs in disease modeling and drug discovery. Peripheral blood mononuclear cells (PBMCs) are attractive targets for reprogramming, because blood is collected by a routine clinical procedure and is a commonly stored material in biobanks. Generation of iPSCs from blood cells has previously been reported using integrative retroviruses, episomal Sendai viruses, and DNA plasmids. However, most of the published protocols require expansion and/or activation of a specific cell population from PBMCs. We have recently collected a PBMC cohort from the Finnish population containing more than 2,000 subjects. Here we report efficient generation of iPSCs directly from PBMCs in feeder-free conditions in approximately 2 weeks. The produced iPSC clones are pluripotent and transgene-free. Together, these properties make this novel method a powerful tool for large-scale reprogramming of PBMCs and for iPSC biobanking.

  17. Multiple exciton generation in nano-crystals revisited: Consistent calculation of the yield based on pump-probe spectroscopy

    CERN Document Server

    Karki, Khadga J; Zheng, Kaibo; Zidek, Karel; Mousa, Abdelrazek; Abdellah, Mohamed A; Messing, Maria; Wallenberg, L Reine; Yartsev, Arkadi; Pullerits, Tonu

    2013-01-01

    Multiple exciton generation (MEG) is a process in which more than one exciton is generated upon the absorption of a high energy photon, typically higher than two times the band gap, in semiconductor nanocrystals. It can be observed experimentally using time resolved spectroscopy such as the transient absorption measurements. Quantification of the MEG yield is usu- ally done by assuming that the bi-exciton signal is twice the signal from a single exciton. Herein we show that this assumption is not always justified and may lead to significant errors in the estimated MEG yields. We develop a methodology to determine proper scaling factors to the signals from the transient absorption experiments. Using the methodology we find modest MEG yields in lead chalcogenide nanocrystals including the nanorods.

  18. Multiple-octave spanning high-energy mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    DEFF Research Database (Denmark)

    Zhou, Binbin; Bache, Morten

    2016-01-01

    supercontinuum generation in the visible, near-IR, and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal is pumped in the mid-IR. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second......-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed. The results were recorded in a commercially available crystal LiInS2 pumped in the 3-4 µm...

  19. Fast high-resolution computer-generated hologram computation using multiple graphics processing unit cluster system.

    Science.gov (United States)

    Takada, Naoki; Shimobaba, Tomoyoshi; Nakayama, Hirotaka; Shiraki, Atsushi; Okada, Naohisa; Oikawa, Minoru; Masuda, Nobuyuki; Ito, Tomoyoshi

    2012-10-20

    To overcome the computational complexity of a computer-generated hologram (CGH), we implement an optimized CGH computation in our multi-graphics processing unit cluster system. Our system can calculate a CGH of 6,400×3,072 pixels from a three-dimensional (3D) object composed of 2,048 points in 55 ms. Furthermore, in the case of a 3D object composed of 4096 points, our system is 553 times faster than a conventional central processing unit (using eight threads).

  20. A novel Multiple-Marker Method for the Early Diagnosis of Oral Squamous Cell Carcinoma

    Directory of Open Access Journals (Sweden)

    Jutta Ries

    2009-01-01

    Full Text Available Objective: Melanoma associated antigens-A (MAGE-A expression is highly specific to cancer cells. Thus, they can be the most suitable targets for the diagnosis of malignancy. The aim of this study was to evaluate the sensitivity of multiple MAGE-A expression analysis for the diagnosis of oral squamous cell carcinoma (OSCC.

  1. Low and high CD8 positive T cells in multiple sclerosis patients.

    Directory of Open Access Journals (Sweden)

    Maryam Izad

    2013-09-01

    Full Text Available Cumulating evidence points to a key role for CD8+ T cells in the pathogenesis of multiple sclerosis.CD8 expression level was believed to be present constantly on the surface of human peripheral blood T cells. However, it was shown that peripheral blood lymphocytes may be divided by the level of CD8 expression, into CD8+high and CD8+low T cells. Now it is well established that the CD8low population of CD8+ T cells demonstrates an activated effector phenotype while the CD8+high T cells have been reported to have regulatory function. In this report we used a flow cytometric assay to compare the frequency of these two subsets in multiple sclerosis patients (n=31 with healthy age- and gender-matched controls (n=18. We found that CD8+ T cells and CD8+low T cells significantly increased in secondary progressive (SP and primary progressive multiple sclerosis (PPMS patients in comparison to controls (p<0.0002 and p<0.004 respectively and also RRMS (p<0.005 and p<0.017 respectively. These results demonstrated the role of CD8low T cells in progressive form of multiple sclerosis.

  2. Carbon fiber enhanced bioelectricity generation in soil microbial fuel cells.

    Science.gov (United States)

    Li, Xiaojing; Wang, Xin; Zhao, Qian; Wan, Lili; Li, Yongtao; Zhou, Qixing

    2016-11-15

    The soil microbial fuel cell (MFC) is a promising biotechnology for the bioelectricity recovery as well as the remediation of organics contaminated soil. However, the electricity production and the remediation efficiency of soil MFC are seriously limited by the tremendous internal resistance of soil. Conductive carbon fiber was mixed with petroleum hydrocarbons contaminated soil and significantly enhanced the performance of soil MFC. The maximum current density, the maximum power density and the accumulated charge output of MFC mixed carbon fiber (MC) were 10, 22 and 16 times as high as those of closed circuit control due to the carbon fiber productively assisted the anode to collect the electron. The internal resistance of MC reduced by 58%, 83% of which owed to the charge transfer resistance, resulting in a high efficiency of electron transfer from soil to anode. The degradation rates of total petroleum hydrocarbons enhanced by 100% and 329% compared to closed and opened circuit controls without the carbon fiber respectively. The effective range of remediation and the bioelectricity recovery was extended from 6 to 20cm with the same area of air-cathode. The mixed carbon fiber apparently enhanced the bioelectricity generation and the remediation efficiency of soil MFC by means of promoting the electron transfer rate from soil to anode. The use of conductively functional materials (e.g. carbon fiber) is very meaningful for the remediation and bioelectricity recovery in the bioelectrochemical remediation.

  3. Electricity generation from rapeseed straw hydrolysates using microbial fuel cells.

    Science.gov (United States)

    Jablonska, Milena A; Rybarczyk, Maria K; Lieder, Marek

    2016-05-01

    Rapeseed straw is an attractive fuel material for microbial fuel cells (MFCs) due to its high content of carbohydrates (more than 60% carbohydrates). This study has demonstrated that reducing sugars can be efficiently extracted from raw rapeseed straw by combination of hydrothermal pretreatment and enzymatic hydrolysis followed by utilization as a fuel in two-chamber MFCs for electrical power generation. The most efficient method of saccharification of this lignocellulosic biomass (17%) turned out hydrothermal pretreatment followed by enzymatic hydrolysis. Electricity was produced using hydrolysate concentrations up to 150 mg/dm(3). The power density reached 54 mW/m(2), while CEs ranged from 60% to 10%, corresponding to the initial reducing sugar concentrations of 10-150 mg/dm(3). The COD degradation rates based on charge calculation increased from 0.445 g COD/m(2)/d for the hydrolysate obtained with the microwave treatment to 0.602 g COD/m(2)/d for the most efficient combination of hydrothermal treatment followed by enzymatic hydrolysis.

  4. Electricity generation from tetrathionate in microbial fuel cells by acidophiles.

    Science.gov (United States)

    Sulonen, Mira L K; Kokko, Marika E; Lakaniemi, Aino-Maija; Puhakka, Jaakko A

    2015-03-02

    Inorganic sulfur compounds, such as tetrathionate, are often present in mining process and waste waters. The biodegradation of tetrathionate was studied under acidic conditions in aerobic batch cultivations and in anaerobic anodes of two-chamber flow-through microbial fuel cells (MFCs). All four cultures originating from biohydrometallurgical process waters from multimetal ore heap bioleaching oxidized tetrathionate aerobically at pH below 3 with sulfate as the main soluble metabolite. In addition, all cultures generated electricity from tetrathionate in MFCs at pH below 2.5 with ferric iron as the terminal cathodic electron acceptor. The maximum current and power densities during MFC operation and in the performance analysis were 79.6 mA m(-2) and 13.9 mW m(-2) and 433 mA m(-2) and 17.6 mW m(-2), respectively. However, the low coulombic efficiency (below 5%) indicates that most of the electrons were directed to other processes, such as aerobic oxidation of tetrathionate and unmeasured intermediates. The microbial community analysis revealed that the dominant species both in the anolyte and on the anode electrode surface of the MFCs were Acidithiobacillus spp. and Ferroplasma spp. This study provides a proof of concept that tetrathionate serves as electron donor for biological electricity production in the pH range of 1.2-2.5.

  5. HIGH EFFICIENCY, LOW EMISSIONS, SOLID OXIDE FUEL CELL SYSTEMS FOR MULTIPLE APPLICATIONS

    Energy Technology Data Exchange (ETDEWEB)

    Sara Ward; Michael A. Petrik

    2004-07-28

    Technology Management Inc. (TMI), teamed with the Ohio Office of Energy Efficiency and Renewable Energy, has engineered, constructed, and demonstrated a stationary, low power, multi-module solid oxide fuel cell (SOFC) prototype system operating on propane and natural gas. Under Phase I, TMI successfully operated two systems in parallel, in conjunction with a single DC-AC inverter and battery bus, and produced net AC electricity. Phase II testing expanded to include alternative and renewable fuels typically available in rural regions of Ohio. The commercial system is expected to have ultra-low pollution, high efficiency, and low noise. The TMI SOFC uses a solid ceramic electrolyte operating at high temperature (800-1000 C) which electrochemically converts gaseous fuels (hydrogen or mixed gases) and oxygen into electricity. The TMI system design oxidizes fuel primarily via electrochemical reactions and uses no burners (which pollute and consume fuel)--resulting in extremely clean exhaust. The use of proprietary sulfur tolerant materials developed by TMI allows system operation without additional fuel pre-processing or sulfur removal. Further, the combination of high operating temperatures and solid state operation increases the potential for higher reliability and efficiencies compared to other types of fuel cells. Applications for the TMI SOFC system cover a wide range of transportation, building, industrial, and military market sectors. A generic technology, fuel cells have the potential to be embodied into multiple products specific to Department of Energy (DOE) Office of Energy Efficiency and Renewable Energy (EERE) program areas including: Fuel Cells and Microturbines, School Buildings, Transportation, and Bioenergy. This program focused on low power stationary applications using a multi-module system operating on a range of common fuels. By producing clean electricity more efficiently (thus using less fuel), fuel cells have the triple effect of cleaning up the

  6. Detection and localization of multiple epicardial electrical generators by a two-dipole ranging technique.

    Science.gov (United States)

    Mirvis, D M; Keller, F W; Ideker, R E; Cox, J W; Dowdie, R F; Zettergren, D G

    1977-10-01

    The ability of a numerical procedure to detect and to localize two experimentally induced, epicardial dipolar generators was tested in 24 isolated, perfused rabbit heart preparations, suspended in an electrolyte-filled spherical tank. Electrocardiograms were recorded from 32 electrodes on the surface of the test chamber before and after placement of each of two epicardial burns. The second lesion was located either 180 degrees, 90 degrees, or 45 degrees from the first. Signals were processed by iterative routines that computed the location of one or two independent dipoles that best reconstruced the observed surface potentials. The computed single dipole acounting for 99.68% of root mean sequare (RMS) surface potential recorded after the first burn was located 0.26 +/- 0.10 cm from the centroid of the lesion. Potentials recorded after the second lesions were fit with two dipoles that accounted for 99.36 +/- 1.51% of RMS surface potentials and that were located 0.42 +/- 0.26 cm and 0.57 +/- 0.49 cm from the centers of the corresponding burn. Seventy-one percent of computed dipoles were located within the visible perimeter of the burn. Thus, two simultaneously active dipolar sources can be detected and accurately localized by rigorous study of the generated electrical field.

  7. A Multiple Z-Pinch Configuration for the Generation of High-Density, Magnetized Plasmas

    Science.gov (United States)

    Tarditi, Alfonso G.

    2015-11-01

    The z-pinch is arguably the most straightforward and economical approach for the generation and confinement of hot plasmas, with a long history of theoretical investigations and experimental developments. While most of the past studies were focused on countering the natural tendency of z-pinches to develop instabilities, this study attempts to take advantage of those unstable regimes to form a quasi-stable plasma, with higher density and temperature, possibly of interest for a fusion reactor concept. For this purpose, a configuration with four z-pinch discharges, with axis parallel to each other and symmetrically positioned, is considered. Electrodes for the generation of the discharges and magnetic coils are arranged to favor the formation of concave discharge patterns. The mutual attraction from the co-streaming discharge currents enhances this pattern, leading to bent plasma streams, all nearing towards the axis. This configuration is intended to excite and sustain a ``kink'' unstable mode for each z-pinch, eventually producing either plasmoid structures, detached from each discharge, or sustained kink patterns: both these cases appear to lead to plasmas merging in the central region. The feasibility of this approach in creating a higher density, hotter, meta-stable plasma regime is investigated computationally, addressing both the kink excitation phase and the dynamics of the converging plasma columns.

  8. AFAP-1L1-mediated actin filaments crosslinks hinder Trypanosoma cruzi cell invasion and intracellular multiplication.

    Science.gov (United States)

    de Araújo, Karine Canuto Loureiro; Teixeira, Thaise Lara; Machado, Fabrício Castro; da Silva, Aline Alves; Quintal, Amanda Pifano Neto; da Silva, Claudio Vieira

    2016-10-01

    Host actin cytoskeleton polymerization has been shown to play an important role during Trypanosoma cruzi internalization into mammalian cell. The structure and dynamics of the actin cytoskeleton in cells are regulated by a vast number of actin-binding proteins. Here we aimed to verify the impact of AFAP-1L1, during invasion and multiplication of T. cruzi. Knocking-down AFAP-1L1 increased parasite cell invasion and intracellular multiplication. Thus, we have shown that the integrity of the machinery formed by AFAP-1L1 in actin cytoskeleton polymerization is important to hinder parasite infection.

  9. Generation of tumor-targeted human T lymphocytes from induced pluripotent stem cells for cancer therapy.

    Science.gov (United States)

    Themeli, Maria; Kloss, Christopher C; Ciriello, Giovanni; Fedorov, Victor D; Perna, Fabiana; Gonen, Mithat; Sadelain, Michel

    2013-10-01

    Progress in adoptive T-cell therapy for cancer and infectious diseases is hampered by the lack of readily available, antigen-specific, human T lymphocytes. Pluripotent stem cells could provide an unlimited source of T lymphocytes, but the therapeutic potential of human pluripotent stem cell-derived lymphoid cells generated to date remains uncertain. Here we combine induced pluripotent stem cell (iPSC) and chimeric antigen receptor (CAR) technologies to generate human T cells targeted to CD19, an antigen expressed by malignant B cells, in tissue culture. These iPSC-derived, CAR-expressing T cells display a phenotype resembling that of innate γδ T cells. Similar to CAR-transduced, peripheral blood γδ T cells, the iPSC-derived T cells potently inhibit tumor growth in a xenograft model. This approach of generating therapeutic human T cells 'in the dish' may be useful for cancer immunotherapy and other medical applications.

  10. Prospects of Graphene as a Potential Carrier-Transport Material in Third-Generation Solar Cells.

    Science.gov (United States)

    Chowdhury, Towhid H; Islam, Ashraful; Mahmud Hasan, A K; Terdi, M Asri Mat; Arunakumari, M; Prakash Singh, Surya; Alam, Md Khorshed; Bedja, Idriss M; Hafidz Ruslan, Mohd; Sopian, Kamaruzzaman; Amin, Nowshad; Akhtaruzzaman, Md

    2016-04-01

    Third-generation solar cells are understood to be the pathway to overcoming the issues and drawbacks of the existing solar cell technologies. Since the introduction of graphene in solar cells, it has been providing attractive properties for the next generation of solar cells. Currently, there are more theoretical predictions rather than practical recognitions in third-generation solar cells. Some of the potential of graphene has been explored in organic photovoltaics (OPVs) and dye-sensitized solar cells (DSSCs), but it has yet to be fully comprehended in the recent third-generation inorganic-organic hybrid perovskite solar cells. In this review, the diverse role of graphene in third-generation OPVs and DSSCs will be deliberated to provide an insight on the prospects and challenges of graphene in inorganic-organic hybrid perovskite solar cells.

  11. Luteolin inhibits Cr(VI)-induced malignant cell transformation of human lung epithelial cells by targeting ROS mediated multiple cell signaling pathways

    Energy Technology Data Exchange (ETDEWEB)

    Pratheeshkumar, Poyil; Son, Young-Ok; Divya, Sasidharan Padmaja; Roy, Ram Vinod; Hitron, John Andrew; Wang, Lei [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Kim, Donghern; Dai, Jin [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Asha, Padmaja [National Centre for Aquatic Animal Health, Cochin University of Science and Technology, Cochin (India); Zhang, Zhuo [Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Wang, Yitao [State Key Laboratory of Quality Research in Chinese Medicine, Institute of Chinese Medical Sciences, University of Macau, Macau (China); Shi, Xianglin, E-mail: xshi5@email.uky.edu [Center for Research on Environmental Disease, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States); Graduate Center for Toxicology, University of Kentucky, 1095 VA Drive, Lexington, KY 40536 (United States)

    2014-12-01

    Hexavalent chromium [Cr(VI)] is a well-known human carcinogen associated with the incidence of lung cancer. Inhibition of metal induced carcinogenesis by a dietary antioxidant is a novel approach. Luteolin, a natural dietary flavonoid found in fruits and vegetables, possesses potent antioxidant and anti-inflammatory activity. We found that short term exposure of human bronchial epithelial cells (BEAS-2B) to Cr(VI) (5 μM) showed a drastic increase in ROS generation, NADPH oxidase (NOX) activation, lipid peroxidation, and glutathione depletion, which were significantly inhibited by the treatment with luteolin in a dose dependent manner. Treatment with luteolin decreased AP-1, HIF-1α, COX-2, and iNOS promoter activity induced by Cr(VI) in BEAS-2B cells. In addition, luteolin protected BEAS-2B cells from malignant transformation induced by chronic Cr(VI) exposure. Moreover, luteolin also inhibited the production of pro-inflammatory cytokines (IL-1β, IL-6, IL-8, TNF-α) and VEGF in chronic Cr(VI) exposed BEAS-2B cells. Western blot analysis showed that luteolin inhibited multiple gene products linked to survival (Akt, Fak, Bcl-2, Bcl-xL), inflammation (MAPK, NF-κB, COX-2, STAT-3, iNOS, TNF-α) and angiogenesis (HIF-1α, VEGF, MMP-9) in chronic Cr(VI) exposed BEAS-2B cells. Nude mice injected with BEAS-2B cells chronically exposed to Cr(VI) in the presence of luteolin showed reduced tumor incidence compared to Cr(VI) alone treated group. Overexpression of catalase (CAT) or SOD2, eliminated Cr(VI)-induced malignant transformation. Overall, our results indicate that luteolin protects BEAS-2B cells from Cr(VI)-induced carcinogenesis by scavenging ROS and modulating multiple cell signaling mechanisms that are linked to ROS. Luteolin, therefore, serves as a potential chemopreventive agent against Cr(VI)-induced carcinogenesis. - Highlights: • Luteolin inhibited Cr(VI)-induced oxidative stress. • Luteolin inhibited chronic Cr(VI)-induced malignant transformation.

  12. Establishment of a Novel Lingual Organoid Culture System: Generation of Organoids Having Mature Keratinized Epithelium from Adult Epithelial Stem Cells

    Science.gov (United States)

    Hisha, Hiroko; Tanaka, Toshihiro; Kanno, Shohei; Tokuyama, Yoko; Komai, Yoshihiro; Ohe, Shuichi; Yanai, Hirotsugu; Omachi, Taichi; Ueno, Hiroo

    2013-11-01

    Despite the strong need for the establishment of a lingual epithelial cell culture system, a simple and convenient culture method has not yet been established. Here, we report the establishment of a novel lingual epithelium organoid culture system using a three-dimensional matrix and growth factors. Histological analyses showed that the generated organoids had both a stratified squamous epithelial cell layer and a stratum corneum. Very recently, we showed via a multicolor lineage tracing method that Bmi1-positive stem cells exist at the base of the epithelial basal layer in the interpapillary pit. Using our new culture system, we found that organoids could be generated by single Bmi1-positive stem cells and that in the established organoids, multiple Bmi1-positive stem cells were generated at the outermost layer. Moreover, we observed that organoids harvested at an early point in culture could be engrafted and maturate in the tongue of recipient mice and that the organoids generated from carcinogen-treated mice had an abnormal morphology. Thus, this culture system presents valuable settings for studying not only the regulatory mechanisms of lingual epithelium but also lingual regeneration and carcinogenesis.

  13. [The multiple links between cilia and planar cell polarity].

    Science.gov (United States)

    Ezan, Jérôme; Montcouquiol, Mireille

    2014-11-01

    Since our seminal study in 2003, much has been written about core planar cell polarity (core PCP) signaling and the inner ear. In just a few years, and using the inner ear as a model system, our understanding of the molecular basis of this signaling pathway and how it can influence the development of tissues in mammals has increased considerably. Recently, a number of studies using various animal models of development have uncovered original relationships between the cilia and PCP, and the study of the hair cells of the inner ear has helped elucidating one of these links. In this review, we highlight the differences of PCP signaling between mammals and invertebrates. In the light of recent results, we sum up our current knowledge about PCP signaling in the mammalian cochlear epithelium and we discuss the impact of recent data in the field. We focus our attention on the interrelationship between asymmetric polarity complexes and the position of the cilium, which is essential for the establishment of the overall tissue polarity.

  14. Generation model of positional values as cell operation during the development of multicellular organisms.

    Science.gov (United States)

    Ogawa, Ken-ichiro; Miyake, Yoshihiro

    2011-03-01

    Many conventional models have used the positional information hypothesis to explain each elementary process of morphogenesis during the development of multicellular organisms. Their models assume that the steady concentration patterns of morphogens formed in an extracellular environment have an important property of positional information, so-called "robustness". However, recent experiments reported that a steady morphogen pattern, the concentration gradient of the Bicoid protein, during early Drosophila embryonic development is not robust for embryo-to-embryo variability. These reports encourage a reconsideration of a long-standing problem in systematic cell differentiation: what is the entity of positional information for cells? And, what is the origin of the robust boundary of gene expression? To address these problems at a cellular level, in this article we pay attention to the re-generative phenomena that show another important property of positional information, "size invariance". In view of regenerative phenomena, we propose a new mathematical model to describe the generation mechanism of a spatial pattern of positional values. In this model, the positional values are defined as the values into which differentiable cells transform a spatial pattern providing positional information. The model is mathematically described as an associative algebra composed of various terms, each of which is the multiplication of some fundamental operators under the assumption that the operators are derived from the remarkable properties of cell differentiation on an amputation surface in regenerative phenomena. We apply this model to the concentration pattern of the Bicoid protein during the anterior-posterior axis formation in Drosophila, and consider the conditions needed to establish the robust boundary of the expression of the hunchback gene.

  15. Reduced Test Pattern Generation of Multiple SIC Vectors with Input and Output Delay Faults

    Directory of Open Access Journals (Sweden)

    P.T.Sairam

    2014-11-01

    Full Text Available In recent years, the design for low power has become one of the greatest challenges in high-performance very large scale integration (VLSI design. Most of the methods focus on the power consumption during normal mode operation, while test mode operation has not normally been a predominant concern. However, it has been found that the power consumed during test mode operation is often much higher than during normal mode operation [1]. This is because most of the consumed power results from the switching activity in the nodes of the circuit under test (CUT, which is much higher during test mode than during normal mode operation [1]–[3]. In the proposed pattern, each generated vector applied to each scan chain is an SIC vector, which can minimize the input transition and reduce test power. In VLSI testing, power reduction is achieved by increasing the correlation between consecutive test patterns.

  16. Diosgenin inhibits superoxide generation in FMLP-activated mouse neutrophils via multiple pathways.

    Science.gov (United States)

    Lin, Y; Jia, R; Liu, Y; Gao, Y; Zeng, X; Kou, J; Yu, B

    2014-12-01

    Diosgenin possesses anti-inflammatory and anticancer properties. Activated neutrophils produce high concentrations of the superoxide anion which is involved in the pathophysiology of inflammation-related diseases and cancer. In the present study, the inhibitory effect and possible mechanisms of diosgenin on superoxide generation were investigated in mouse bone marrow neutrophils. Diosgenin potently and concentration-dependently inhibited the extracellular and intracellular superoxide anion generation in Formyl-Met-Leu-Phe (FMLP)- activated neutrophils, with IC50 values of 0.50 ± 0.08 μM and 0.66 ± 0.13 μM, respectively. Such inhibition was not mediated by scavenging the superoxide anion or by a cytotoxic effect. Diosgenin inhibited the phosphorylation of p47phox and membrane translocation of p47phox and p67phox, and thus blocking the assembly of nicotinamide adenine dinucleotide phosphate oxidase. Moreover, cellular cyclic adenosine monophosphate (cAMP) levels and protein kinase A (PKA) expression were also effectively increased by diosgenin. It attenuated FMLP-induced increase of phosphorylation of cytosolic phospholipase A (cPLA2), p21-activated kinase (PAK), Akt, p38 mitogen-activated protein kinase (p38MAPK), extracellular signal-regulated kinase (ERK1/2), and c-Jun N-terminal kinase (JNK). Our data indicate that diosgenin exhibits inhibitory effects on superoxide anion production through the blockade of cAMP, PKA, cPLA2, PAK, Akt and MAPKs signaling pathways. The results may explain the clinical implications of diosgenin in the treatment of inflammation-related disorders.

  17. Selective purging of human multiple myeloma cells from autologous stem cell transplant grafts using oncolytic myxoma virus

    OpenAIRE

    Bartee, Eric; Chan, Winnie S.; Moreb, Jan S.; Cogle, Christopher R.; McFadden, Grant

    2012-01-01

    Autologous stem cell transplantation (ASCT) and novel therapies have improved overall survival of patients with multiple myeloma; however, most patients relapse and eventually succumb to their disease. Evidence indicates that residual cancer cells contaminate autologous grafts and may contribute to early relapses after ASCT. Here, we demonstrate that ex vivo treatment with an oncolytic poxvirus called myxoma virus results in specific elimination of human myeloma cells by inducing rapid cellul...

  18. Multiple loci are associated with white blood cell phenotypes.

    Directory of Open Access Journals (Sweden)

    Michael A Nalls

    2011-06-01

    Full Text Available White blood cell (WBC count is a common clinical measure from complete blood count assays, and it varies widely among healthy individuals. Total WBC count and its constituent subtypes have been shown to be moderately heritable, with the heritability estimates varying across cell types. We studied 19,509 subjects from seven cohorts in a discovery analysis, and 11,823 subjects from ten cohorts for replication analyses, to determine genetic factors influencing variability within the normal hematological range for total WBC count and five WBC subtype measures. Cohort specific data was supplied by the CHARGE, HeamGen, and INGI consortia, as well as independent collaborative studies. We identified and replicated ten associations with total WBC count and five WBC subtypes at seven different genomic loci (total WBC count-6p21 in the HLA region, 17q21 near ORMDL3, and CSF3; neutrophil count-17q21; basophil count- 3p21 near RPN1 and C3orf27; lymphocyte count-6p21, 19p13 at EPS15L1; monocyte count-2q31 at ITGA4, 3q21, 8q24 an intergenic region, 9q31 near EDG2, including three previously reported associations and seven novel associations. To investigate functional relationships among variants contributing to variability in the six WBC traits, we utilized gene expression- and pathways-based analyses. We implemented gene-clustering algorithms to evaluate functional connectivity among implicated loci and showed functional relationships across cell types. Gene expression data from whole blood was utilized to show that significant biological consequences can be extracted from our genome-wide analyses, with effect estimates for significant loci from the meta-analyses being highly corellated with the proximal gene expression. In addition, collaborative efforts between the groups contributing to this study and related studies conducted by the COGENT and RIKEN groups allowed for the examination of effect homogeneity for genome-wide significant associations across

  19. CD34+ cells cultured in stem cell factor and interleukin-2 generate CD56+ cells with antiproliferative effects on tumor cell lines

    Directory of Open Access Journals (Sweden)

    Hensel Nancy

    2005-04-01

    Full Text Available Abstract In vitro stimulation of CD34+ cells with IL-2 induces NK cell differentiation. In order to define the stages of NK cell development, which influence their generation from CD34 cells, we cultured G-CSF mobilized peripheral blood CD34+ cells in the presence of stem cell factor and IL-2. After three weeks culture we found a diversity of CD56+ subsets which possessed granzyme A, but lacked the cytotoxic apparatus required for classical NK-like cytotoxicity. However, these CD56+ cells had the unusual property of inhibiting proliferation of K562 and P815 cell lines in a cell-contact dependent fashion.

  20. Generation of Corneal Keratocytes from Human Embryonic Stem Cells.

    Science.gov (United States)

    Hertsenberg, Andrew J; Funderburgh, James L

    2016-01-01

    Human Embryonic Stem Cells (hESC) offer an important resource as a limitless supply of any differentiated cell type of the human body. Keratocytes, cells from the corneal stroma, may have the potential for restoration of vision in cell therapy and biomedical engineering applications, but these specialized cells are not readily expanded in vitro. Here we describe a two-part method to produce keratocytes from the H1 hESC cell line. The hESC cells, maintained and expanded in feeder-free culture medium are first differentiated to neural crest cells using the stromal-derived inducing activity (SDIA) of the PA6 mouse embryonic fibroblast cell line. The resulting neural crest cells are selected by their expression of cell-surface CD271 and subsequently cultured as 3D pellets in a defined differentiation medium to induce a keratocyte phenotype.

  1. Successful imiquimod treatment of multiple basal cell carcinomas after radiation therapy for Hodgkin's disease.

    Science.gov (United States)

    Beyeler, Mirjam; Urosevic, Mirjana; Pestalozzi, Bernhard; Dummer, Reinhard

    2005-01-01

    We present a case of a 55-year-old male patient who developed five basal cell carcinomas 23 years after radiation therapy of Hodgkin's disease. In 1980 he received radiation therapy twice. Due to relapses, he was treated with aggressive polychemotherapy and underwent autologous stem cell transplantation, which then led to complete remission. Until now he is in complete remission. However, multiple superficial basal cell carcinomas have developed on irradiation fields that have been successfully treated by imiquimod.

  2. Application of multiple graphene layers as catalyst support material in fuel cells

    OpenAIRE

    Saner, Burcu; YÜRÜM, YUDA; Yurum, Yuda

    2010-01-01

    The fuel cell electrode layer is a significant part of a fuel cell. The electrode layer is composed of the catalyst and porous electrode or gas diffusion layer. Catalyst has critical importance due to the influence on the cost and durability of fuel cells. The production of novel catalyst support materials could open up new ways in order to ensure the catalytic activity by lowering the amount of catalyst loaded [1]. At this point, utilization of multiple graphene layers as catalyst support...

  3. Mechanisms of Oxidative Damage in Multiple Sclerosis and a Cell Therapy Approach to Treatment

    Directory of Open Access Journals (Sweden)

    Jonathan Witherick

    2011-01-01

    Full Text Available Although significant advances have recently been made in the understanding and treatment of multiple sclerosis, reduction of long-term disability remains a key goal. Evidence suggests that inflammation and oxidative stress within the central nervous system are major causes of ongoing tissue damage in the disease. Invading inflammatory cells, as well as resident central nervous system cells, release a number of reactive oxygen and nitrogen species which cause demyelination and axonal destruction, the pathological hallmarks of multiple sclerosis. Reduction in oxidative damage is an important therapeutic strategy to slow or halt disease processes. Many drugs in clinical practice or currently in trial target this mechanism. Cell-based therapies offer an alternative source of antioxidant capability. Classically thought of as being important for myelin or cell replacement in multiple sclerosis, stem cells may, however, have a more important role as providers of supporting factors or direct attenuators of the disease. In this paper we focus on the antioxidant properties of mesenchymal stem cells and discuss their potential importance as a cell-based therapy for multiple sclerosis.

  4. Escherichia coli Quorum-Sensing EDF, A Peptide Generated by Novel Multiple Distinct Mechanisms and Regulated by trans-Translation

    Directory of Open Access Journals (Sweden)

    Sathish Kumar

    2016-01-01

    Full Text Available Eshcerichia coli mazEF is a stress-induced toxin-antitoxin module mediating cell death and requiring a quorum-sensing (QS extracellular death factor (EDF, the pentapeptide NNWNN. Here we uncovered several distinct molecular mechanisms involved in its generation from the zwf mRNA encoding glucose-6-phosphate dehydrogenase. In particular, we show that, under stress conditions, the endoribonuclease MazF cleaves specific ACA sites, thereby generating a leaderless zwf mRNA which is truncated 30 codons after the EDF-encoding region. Since the nascent ribosome peptide exit tunnel can accommodate up to 40 amino acids, this arrangement allows the localization of the EDF residues inside the tunnel when the ribosome is stalled at the truncation site. Moreover, ribosome stalling activates the trans-translation system, which provides a means for the involvement of ClpPX in EDF generation. Furthermore, the trans-translation is described as a regulatory system that attenuated the generation of EDF, leading to low levels of EDF in the single cell. Therefore, the threshold EDF molecule concentration required is achieved only by the whole population, as expected for QS.

  5. Simulation of multi-photon emission isotopes using time-resolved SimSET multiple photon history generator

    Energy Technology Data Exchange (ETDEWEB)

    Chiang, Chih-Chieh; Lin, Hsin-Hon; Lin, Chang-Shiun; Chuang, Keh-Shih [Department of Biomedical Engineering and Environmental Sciences, National Tsing-HuaUniversity, Hsinchu, Taiwan (China); Jan, Meei-Ling [Health Physics Division, Institute of Nuclear Energy Research, Atomic Energy Council, Taoyuan, Taiwan (China)

    2015-07-01

    Abstract-Multiple-photon emitters, such as In-111 or Se-75, have enormous potential in the field of nuclear medicine imaging. For example, Se-75 can be used to investigate the bile acid malabsorption and measure the bile acid pool loss. The simulation system for emission tomography (SimSET) is a well-known Monte Carlo simulation (MCS) code in nuclear medicine for its high computational efficiency. However, current SimSET cannot simulate these isotopes due to the lack of modeling of complex decay scheme and the time-dependent decay process. To extend the versatility of SimSET for simulation of those multi-photon emission isotopes, a time-resolved multiple photon history generator based on SimSET codes is developed in present study. For developing the time-resolved SimSET (trSimSET) with radionuclide decay process, the new MCS model introduce new features, including decay time information and photon time-of-flight information, into this new code. The half-life of energy states were tabulated from the Evaluated Nuclear Structure Data File (ENSDF) database. The MCS results indicate that the overall percent difference is less than 8.5% for all simulation trials as compared to GATE. To sum up, we demonstrated that time-resolved SimSET multiple photon history generator can have comparable accuracy with GATE and keeping better computational efficiency. The new MCS code is very useful to study the multi-photon imaging of novel isotopes that needs the simulation of lifetime and the time-of-fight measurements. (authors)

  6. Generation of human pluripotent stem cell-derived hepatocyte-like cells for drug toxicity screening.

    Science.gov (United States)

    Takayama, Kazuo; Mizuguchi, Hiroyuki

    2017-02-01

    Because drug-induced liver injury is one of the main reasons for drug development failures, it is important to perform drug toxicity screening in the early phase of pharmaceutical development. Currently, primary human hepatocytes are most widely used for the prediction of drug-induced liver injury. However, the sources of primary human hepatocytes are limited, making it difficult to supply the abundant quantities required for large-scale drug toxicity screening. Therefore, there is an urgent need for a novel unlimited, efficient, inexpensive, and predictive model which can be applied for large-scale drug toxicity screening. Human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are able to replicate indefinitely and differentiate into most of the body's cell types, including hepatocytes. It is expected that hepatocyte-like cells generated from human ES/iPS cells (human ES/iPS-HLCs) will be a useful tool for drug toxicity screening. To apply human ES/iPS-HLCs to various applications including drug toxicity screening, homogenous and functional HLCs must be differentiated from human ES/iPS cells. In this review, we will introduce the current status of hepatocyte differentiation technology from human ES/iPS cells and a novel method to predict drug-induced liver injury using human ES/iPS-HLCs.

  7. Generation of Alveolar Epithelial Spheroids via Isolated Progenitor Cells from Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Shimpei Gotoh

    2014-09-01

    Full Text Available No methods for isolating induced alveolar epithelial progenitor cells (AEPCs from human embryonic stem cells (hESCs and induced pluripotent stem cells (hiPSCs have been reported. Based on a study of the stepwise induction of alveolar epithelial cells (AECs, we identified carboxypeptidase M (CPM as a surface marker of NKX2-1+ “ventralized” anterior foregut endoderm cells (VAFECs in vitro and in fetal human and murine lungs. Using SFTPC-GFP reporter hPSCs and a 3D coculture system with fetal human lung fibroblasts, we showed that CPM+ cells isolated from VAFECs differentiate into AECs, demonstrating that CPM is a marker of AEPCs. Moreover, 3D coculture differentiation of CPM+ cells formed spheroids with lamellar-body-like structures and an increased expression of surfactant proteins compared with 2D differentiation. Methods to induce and isolate AEPCs using CPM and consequently generate alveolar epithelial spheroids would aid human pulmonary disease modeling and regenerative medicine.

  8. Generation of a Drug-inducible Reporter System to Study Cell Reprogramming in Human Cells*

    Science.gov (United States)

    Ruiz, Sergio; Panopoulos, Athanasia D.; Montserrat, Nuria; Multon, Marie-Christine; Daury, Aurélie; Rocher, Corinne; Spanakis, Emmanuel; Batchelder, Erika M.; Orsini, Cécile; Deleuze, Jean-François; Izpisua Belmonte, Juan Carlos

    2012-01-01

    Reprogramming of somatic cells into induced pluripotent stem cells is achieved by the expression of defined transcription factors. In the last few years, reprogramming strategies on the basis of doxycycline-inducible lentiviruses in mouse cells became highly powerful for screening purposes when the expression of a GFP gene, driven by the reactivation of endogenous stem cell specific promoters, was used as a reprogramming reporter signal. However, similar reporter systems in human cells have not been generated. Here, we describe the derivation of drug-inducible human fibroblast-like cell lines that express different subsets of reprogramming factors containing a GFP gene under the expression of the endogenous OCT4 promoter. These cell lines can be used to screen functional substitutes for reprogramming factors or modifiers of reprogramming efficiency. As a proof of principle of this system, we performed a screening of a library of pluripotent-enriched microRNAs and identified hsa-miR-519a as a novel inducer of reprogramming efficiency. PMID:23019325

  9. Generation of multiple analog pulses with different duty cycles within VME control system for ICRH Aditya system

    Science.gov (United States)

    Joshi, Ramesh; Singh, Manoj; Jadav, H. M.; Misra, Kishor; Kulkarni, S. V.; ICRH-RF Group

    2010-02-01

    Ion Cyclotron Resonance Heating (ICRH) is a promising heating method for a fusion device due to its localized power deposition profile, a direct ion heating at high density, and established technology for high RF power generation and transmission at low cost. Multiple analog pulse with different duty cycle in master of digital pulse for Data acquisition and Control system for steady state RF ICRH System(RF ICRH DAC) to be used for operating of RF Generator in Aditya to produce pre ionization and second analog pulse will produce heating. The control system software is based upon single digital pulse operation for RF source. It is planned to integrate multiple analog pulses with different duty cycle in master of digital pulse for Data acquisition and Control system for RF ICRH System(RF ICRH DAC) to be used for operating of RF Generator in Aditya tokamak. The task of RF ICRH DAC is to control and acquisition of all ICRH system operation with all control loop and acquisition for post analysis of data with java based tool. For pre ionization startup as well as heating experiments using multiple RF Power of different powers and duration. The experiment based upon the idea of using single RF generator to energize antenna inside the tokamak to radiate power twise, out of which first analog pulse will produce pre ionization and second analog pulse will produce heating. The whole system is based on standard client server technology using tcp/ip protocol. DAC Software is based on linux operating system for highly reliable, secure and stable system operation in failsafe manner. Client system is based on tcl/tk like toolkit for user interface with c/c++ like environment which is reliable programming languages widely used on stand alone system operation with server as vxWorks real time operating system like environment. The paper is focused on the Data acquisition and monitoring system software on Aditya RF ICRH System with analog pulses in slave mode with digital pulse in

  10. Factorial combinations of protein interactions generate a multiplicity of florigen activation complexes in wheat and barley.

    Science.gov (United States)

    Li, Chengxia; Lin, Huiqiong; Dubcovsky, Jorge

    2015-10-01

    The FLOWERING LOCUS T (FT) protein is a central component of a mobile flowering signal (florigen) that is transported from leaves to the shoot apical meristem (SAM). Two FT monomers and two DNA-binding bZIP transcription factors interact with a dimeric 14-3-3 protein bridge to form a hexameric protein complex. This complex, designated as the 'florigen activation complex' (FAC), plays a critical role in flowering. The wheat homologue of FT, designated FT1 (= VRN3), activates expression of VRN1 in the leaves and the SAM, promoting flowering under inductive long days. In this study, we show that FT1, other FT-like proteins, and different FD-like proteins, can interact with multiple wheat and barley 14-3-3 proteins. We also identify the critical amino acid residues in FT1 and FD-like proteins required for their interactions, and demonstrate that 14-3-3 proteins are necessary bridges to mediate the FT1-TaFDL2 interaction. Using in vivo bimolecular fluorescent complementation (BiFC) assays, we demonstrate that the interaction between FT1 and 14-3-3 occurs in the cytoplasm, and that this complex is then translocated to the nucleus, where it interacts with TaFDL2 to form a FAC. We also demonstrate that a FAC including FT1, TaFDL2 and Ta14-3-3C can bind to the VRN1 promoter in vitro. Finally, we show that relative transcript levels of FD-like and 14-3-3 genes vary among tissues and developmental stages. Since FD-like proteins determine the DNA specificity of the FACs, variation in FD-like gene expression can result in spatial and temporal modulation of the effects of mobile FT-like signals.

  11. Deficient Fas expression by CD4+ CCR5+ T cells in multiple sclerosis

    DEFF Research Database (Denmark)

    Julià, Eva; Montalban, Xavier; Al-Zayat, Hammad;

    2006-01-01

    OBJECTIVE: To evaluate whether T cells expressing CCR5 and CXCR3 from multiple sclerosis (MS) patients are more resistant to apoptosis. METHODS: Expression of CD69, TNF-R1, Fas, FasL, bcl-2, and bax was investigated in 41 MS patients and 12 healthy controls by flow cytometry in CD4+ and CD8+ T...... cells expressing CCR5 and CXCR3. RESULTS: In MS patients, the percentage of CD69 was increased and Fas expression decreased in CD4+ CCR5+ T cells. INTERPRETATION: The lower Fas expression in activated CD4+ CCR5+ T cells might contribute to disease pathogenesis by prolonging cell survival and favoring...

  12. A novel method to generate and culture human mast cells: Peripheral CD34+ stem cell-derived mast cells (PSCMCs).

    Science.gov (United States)

    Schmetzer, Oliver; Valentin, Patricia; Smorodchenko, Anna; Domenis, Rossana; Gri, Giorgia; Siebenhaar, Frank; Metz, Martin; Maurer, Marcus

    2014-11-01

    The identification and characterization of human mast cell (MC) functions are hindered by the shortage of MC populations suitable for investigation. Here, we present a novel technique for generating large numbers of well differentiated and functional human MCs from peripheral stem cells (=peripheral stem cell-derived MCs, PSCMCs). Innovative and key features of this technique include 1) the use of stem cell concentrates, which are routinely discarded by blood banks, as the source of CD34+ stem cells, 2) cell culture in serum-free medium and 3) the addition of LDL as well as selected cytokines. In contrast to established and published protocols that use CD34+ or CD133+ progenitor cells from full blood, we used a pre-enriched cell population obtained from stem cell concentrates, which yielded up to 10(8) differentiated human MCs per batch after only three weeks of culture starting with 10(6) total CD34+ cells. The total purity on MCs (CD117+, FcεR1+) generated by this method varied between 55 and 90%, of which 4-20% were mature MCs that contain tryptase and chymase and show expression of FcεRI and CD117 in immunohistochemistry. PSCMCs showed robust histamine release in response to stimulation with anti-FcεR1 or IgE/anti-IgE, and increased proliferation and differentiation in response to IL-1β or IFN-γ. Taken together, this new protocol of the generation of large numbers of human MCs provides for an innovative and suitable option to investigate the biology of human MCs.

  13. Using Flow Electrodes in Multiple Reactors in Series for Continuous Energy Generation from Capacitive Mixing

    KAUST Repository

    Hatzell, Marta C.

    2014-12-09

    Efficient conversion of “mixing energy” to electricity through capacitive mixing (CapMix) has been limited by low energy recoveries, low power densities, and noncontinuous energy production resulting from intermittent charging and discharging cycles. We show here that a CapMix system based on a four-reactor process with flow electrodes can generate constant and continuous energy, providing a more flexible platform for harvesting mixing energy. The power densities were dependent on the flow-electrode carbon loading, with 5.8 ± 0.2 mW m–2 continuously produced in the charging reactor and 3.3 ± 0.4 mW m–2 produced in the discharging reactor (9.2 ± 0.6 mW m–2 for the whole system) when the flow-electrode carbon loading was 15%. Additionally, when the flow-electrode electrolyte ion concentration increased from 10 to 20 g L–1, the total power density of the whole system (charging and discharging) increased to 50.9 ± 2.5 mW m–2.

  14. Estimation of dimensions and orientation of multiple riverine dune generations using spectral moments

    Science.gov (United States)

    Lisimenka, Aliaksandr; Kubicki, Adam

    2017-02-01

    A new spectral analysis technique is proposed for rhythmic bedform quantification, based on the 2D Fourier transform involving the calculation of a set of low-order spectral moments. The approach provides a tool for efficient quantification of bedform length and height as well as spatial crest-line alignment. Contrary to the conventional method, it not only describes the most energetic component of an undulating seabed surface but also retrieves information on its secondary structure without application of any band-pass filter of which the upper and lower cut-off frequencies are a priori unknown. Validation is based on bathymetric data collected in the main Vistula River mouth area (Przekop Wisły), Poland. This revealed two generations (distinct groups) of dunes which are migrating seawards along distinct paths, probably related to the hydrological regime of the river. The data enable the identification of dune divergence and convergence zones. The approach proved successful in the parameterisation of topographic roughness, an essential aspect in numerical modelling studies.

  15. Quantification of multiple fault parameters in flexible turbo-generator systems with incomplete rundown vibration data

    Science.gov (United States)

    Lal, Mohit; Tiwari, Rajiv

    2013-12-01

    A turbo-generator system of the modern rotating machinery consists of the driver and driven shafts, which are coupled through flexible couplings and mounted on flexible bearings. Dynamic characterisation of vital machine elements of such rotating machinery is a challenging problem for reliable and accurate response predictions. In this paper, a key intention is to estimate the bearing and coupling dynamic parameters along with residual unbalances at predefined planes, and the misalignment forces and moments at the coupling based on the rundown vibration data. To tackle a practical difficulty of limited measurements and a numerical difficulty of the conventional dynamic condensation in the development of identification algorithm, a novel condensation technique has been implemented especially to overcome measurement of transverse rotational DOFs. Numerical examples are also presented to show the effectiveness of the proposed method. The measurement noise has been added in numerically simulated responses that are used in the present algorithm to identify the parameters and it is found to be robust. Modelling errors of few physical parameters are also considered and estimates are found to be very good.

  16. Seismic Tremor Generated by Multiple Processes, Vatnajökull Glacier, Iceland

    Science.gov (United States)

    Eibl, E. P. S.; Bean, C. J.; Vogfjord, K. S.

    2014-12-01

    Vatnajökull glacier in eastern Iceland covers five volcanic systems in which Bárdarbunga and Grimsvötn are the most active volcanoes. Whilst fluctuating ice cover mitigates against year-round near-field monitoring of the volcanoes, important information can be gleaned from stations deployed at the glacier's edge. Glacial cover significantly increases the complexity of and the solution space for observed seismic signals. For example tremor can be caused by magmatic activity, intra-glacier interactions, melt water flow or hydrothermal boiling. A better understanding of hazard requires a more indepth understanding of the signals generated by these processes at Vatnajökull. We augmented the sparse network in the region with two seven-element broad band seismometer arrays west of Vatnajökull, in Jökulheimar and near Laki respectively. Observed seismic tremor-like transients (< 2 Hz) originating from two cauldrons west of Grimsvötn are directly associated with small flooding events (jökulhaups), as subsequently confirmed by radar and hydrological observations. For larger longer duration floods dominant harmonic tremor frequencies of 2 to 4 Hz are observed, but they change in amplitude and frequency with time, likely reflecting variable feed and flow rates, associated with a moving source. Our aim is to 'fingerprint' these events such that they can be distinguished from seismic tremor signals associated with magmatic activity.

  17. DSM generation using multiple radar data for relief change detection in North Peloponnese

    Science.gov (United States)

    Nikolakopoulos, Konstantinos G.; Kyriou, Aggeliki; Sabatakakis, Nikolaos; Anastassopoulos, Vassilis

    2016-08-01

    Interferometry constitutes a technique of acquisition height information with a range of applications, such as Digital Surface Model (DSM) generation in order to monitoring the Earth's surface. This work is focused on interferometric DSM creation utilizing radar data of Sentinel-1 and TerraSAR-X missions, covering the wider area of Northern Peloponnese. This area is characterized of loose geological formations and intense active tectonics resulting in continuous and intense relief changes. In this context, the accuracy and the update of the DSMs is essential in order to detect and map any terrain change. The selection of Sentinel-1 and TerraSAR-X images was based on the fact that both missions provide timely, with short revisiting period and satisfactory spatial resolution data. In particular, two ranges of radar data from both missions were submitted in interferometric process aimed at DSM creation. The produced DSMs were compared both visually and statistically to a very accurate reference DSM produced from airphotos by the Greek Cadastral. Furthermore, in order to estimate the accuracy of the DSMs and detect variations of terrain's surface, points of known elevation have been used. 2D RMSE, correlation and the percentile value were computed and the results are presented.

  18. [Effect of AZD8330 on proliferation and apoptosis of multiple myeloma cells].

    Science.gov (United States)

    Yao, Yao; Bian, Yue-Ping; Xia, Dan-Dan; Pan, Bin; Niu, Ming-Shan; Zhao, Kai; Zeng, Ling-Yu; Xu, Kai-Lin

    2014-10-01

    This study was aimed to investigate the effect of MEK inhibitor AZD8330 on proliferation and apoptosis of multiple myeloma IM9 and NCI-H929 cell lines and its possible mechanism. These two cell line cells were exposed to different concentrations of AZD8330 for 48 h. The CCK-8 assay was used to detect cell viability and the IC50 value at 48 h. These above-mentioned IM9 and NCI-H929 cells were treated with 5,10 and 100 nmol/L of AZD8330, then the change of cell cycle was analysed by flow cytometry with PI staining. The Wester blot was used to detect the expression levels of cyclin D and cyclin E, and multiple myeloma cells were treated with 10, 100, 1000 and 2000 nmol/L of AZD8330, the AnnexinV/7-AAD double staining was used to analyse cell apoptosis and the Western blot was used to detect the expression level of caspase-3. The results showed that AZD8330 could significantly inhibit the cell viability of IM9 and NCI-H929 cell lines in a time-and dose-dependent manner, the IC50 value (48 h) of IM9 and NCI-H929 were 19.88 ± 2.7 nmol/L and 29.3 ± 2.03 nmol/L respectively, these two cell lines were arrested on G1 phase of cell cycle, the apoptosis cells increased along with enhancement of AZD8330 concentration, and the expression level of cleaved caspase-3 protein was up-regulated. It is concluded that AZD8330 can efficiently inhibit the proliferation of NCI-H929 and IM9 cell lines, and induce apoptosis, suggesting that the AZD8330 may be a potential chemotherapeutic candidate for multiple myeloma therapy.

  19. Dystroglycan versatility in cell adhesion: a tale of multiple motifs

    Directory of Open Access Journals (Sweden)

    Winder Steve J

    2010-02-01

    Full Text Available Abstract Dystroglycan is a ubiquitously expressed heterodimeric adhesion receptor. The extracellular α-subunit makes connections with a number of laminin G domain ligands including laminins, agrin and perlecan in the extracellular matrix and the transmembrane β-subunit makes connections to the actin filament network via cytoskeletal linkers including dystrophin, utrophin, ezrin and plectin, depending on context. Originally discovered as part of the dystrophin glycoprotein complex of skeletal muscle, dystroglycan is an important adhesion molecule and signalling scaffold in a multitude of cell types and tissues and is involved in several diseases. Dystroglycan has emerged as a multifunctional adhesion platform with many interacting partners associating with its short unstructured cytoplasmic domain. Two particular hotspots are the cytoplasmic juxtamembrane region and at the very carboxy terminus of dystroglycan. Regions which between them have several overlapping functions: in the juxtamembrane region; a nuclear localisation signal, ezrin/radixin/moesin protein, rapsyn and ERK MAP Kinase binding function, and at the C terminus a regulatory tyrosine governing WW, SH2 and SH3 domain interactions. We will discuss the binding partners for these motifs and how their interactions and regulation can modulate the involvement of dystroglycan in a range of different adhesion structures and functions depending on context. Thus dystroglycan presents as a multifunctional scaffold involved in adhesion and adhesion-mediated signalling with its functions under exquisite spatio-temporal regulation.

  20. Germ Cell Cancer and Multiple Relapses: Toxicity and Survival

    DEFF Research Database (Denmark)

    Lauritsen, Jakob; Kier, Maria G.G.; Mortensen, Mette S.

    2015-01-01

    Purpose: A small number of patients with germ cell cancer (GCC) receive more than one line of treatment for disseminated disease. The purpose of this study was to evaluate late toxicity and survival in an unselected cohort of patients who experienced relapse after receiving first-line treatment......, compared with patients treated with only orchiectomy, had an increased risk for a second cancer (hazard ratio [HR], 3.2; 95% CI, 1.9 to 5.5), major cardiovascular disease (HR, 1.9; 95% CI, 1.0 to 3.3), pulmonary disease (HR, 2.0; 95% CI, 1.0 to 3.8), GI disease (HR, 7.3; 95% CI, 3.6 to 14.8), renal...... for disseminated disease. Methods: From the Danish Testicular Cancer database, we identified all patients who received more than one line of treatment for disseminated disease. Information about late toxicity and mortality was obtained by means of linkage to national registers. Prognostic factors for relapse...

  1. Generation of Neural Crest-Like Cells From Human Periodontal Ligament Cell-Derived Induced Pluripotent Stem Cells.

    Science.gov (United States)

    Tomokiyo, Atsushi; Hynes, Kim; Ng, Jia; Menicanin, Danijela; Camp, Esther; Arthur, Agnes; Gronthos, Stan; Mark Bartold, Peter

    2017-02-01

    Neural crest cells (NCC) hold great promise for tissue engineering, however the inability to easily obtain large numbers of NCC is a major factor limiting their use in studies of regenerative medicine. Induced pluripotent stem cells (iPSC) are emerging as a novel candidate that could provide an unlimited source of NCC. In the present study, we examined the potential of neural crest tissue-derived periodontal ligament (PDL) iPSC to differentiate into neural crest-like cells (NCLC) relative to iPSC generated from a non-neural crest derived tissue, foreskin fibroblasts (FF). We detected high HNK1 expression during the differentiation of PDL and FF iPSC into NCLC as a marker for enriching for a population of cells with NCC characteristics. We isolated PDL iPSC- and FF iPSC-derived NCLC, which highly expressed HNK1. A high proportion of the HNK1-positive cell populations generated, expressed the MSC markers, whilst very few cells expressed the pluripotency markers or the hematopoietic markers. The PDL and FF HNK1-positive populations gave rise to smooth muscle, neural, glial, osteoblastic and adipocytic like cells and exhibited higher expression of smooth muscle, neural, and glial cell-associated markers than the PDL and FF HNK1-negative populations. Interestingly, the HNK1-positive cells derived from the PDL-iPSC exhibited a greater ability to differentiate into smooth muscle, neural, glial cells and adipocytes, than the HNK1-positive cells derived from the FF-iPSC. Our work suggests that HNK1-enriched NCLC from neural crest tissue-derived iPSC more closely resemble the phenotypic and functional hallmarks of NCC compared to the HNK1-low population and non-neural crest iPSC-derived NCLC. J. Cell. Physiol. 232: 402-416, 2017. © 2016 Wiley Periodicals, Inc.

  2. Genetic risk and a primary role for cell-mediated immune mechanisms in multiple sclerosis

    DEFF Research Database (Denmark)

    Sawcer, Stephen; Hellenthal, Garrett; Pirinen, Matti;

    2011-01-01

    Multiple sclerosis is a common disease of the central nervous system in which the interplay between inflammatory and neurodegenerative processes typically results in intermittent neurological disturbance followed by progressive accumulation of disability. Epidemiological studies have shown that g...... the independent protective effect attributable to the class I region. Immunologically relevant genes are significantly overrepresented among those mapping close to the identified loci and particularly implicate T-helper-cell differentiation in the pathogenesis of multiple sclerosis....

  3. [A Case of Synchronous Multiple Esophageal Cancers Composed of Squamous Cell Carcinoma and Barrett's Adenocarcinoma].

    Science.gov (United States)

    Kobayashi, Toshiyuki; Shiozaki, Atsushi; Fujiwara, Hitoshi; Konishi, Hirotaka; Arita, Tomohiro; Kosuga, Toshiyuki; Morimura, Ryo; Murayama, Yasutoshi; Komatsu, Shuhei; Kuriu, Yoshiaki; Ikoma, Hisashi; Nakanishi, Masayoshi; Ichikawa, Daisuke; Okamoto, Kazuma; Otsuji, Eigo

    2015-11-01

    A 67-year-old man was admitted to our hospital for treatment for multiple superficial esophageal cancers. Screening upper gastrointestinal endoscopy examination revealed a superficial squamous cell carcinoma (SCC) at the middle thoracic esophagus and Barrett's epithelium and a superficial adenocarcinoma at the abdominal esophagus. We performed a subtotal esophagectomy with gastric tube reconstruction via the retrosternal route. Pathological examination revealed a Barrett's adenocarcinoma at the abdominal esophagus. Esophageal cancer is thought to be a multicentric disease, and we sometimes find multiple esophageal cancers. In Japan, most cases of multiple esophageal cancers are composed of SCCs, and the occurrence of multiple esophageal cancers composed of SCC and Barrett's adenocarcinoma is rare. In contrast, the number of the patients with Barrett's esophagus is increasing, and the number of the patients with Barrett's adenocarcinoma also seems to be on the rise. Therefore, it is important be aware of the possibility of multiple esophageal cancers composed of SCC and Barrett's adenocarcinoma while making diagnoses.

  4. Weighted Hashing with Multiple Cues for Cell-Level Analysis of Histopathological Images.

    Science.gov (United States)

    Zhang, Xiaofan; Su, Hai; Yang, Lin; Zhang, Shaoting

    2015-01-01

    Recently, content-based image retrieval has been investigated for histopathological image analysis, focusing on improving the accuracy and scalability. The main motivation is to interpret a new image (i.e., query image) by searching among a potentially large-scale database of training images in real-time. Hashing methods have been employed because of their promising performance. However, most previous works apply hashing algorithms on the whole images, while the important information of histopathological images usually lies in individual cells. In addition, they usually only hash one type of features, even though it is often necessary to inspect multiple cues of cells. Therefore, we propose a probabilistic-based hashing framework to model multiple cues of cells for accurate analysis of histopathological images. Specifically, each cue of a cell is compressed as binary codes by kernelized and supervised hashing, and the importance of each hash entry is determined adaptively according to its discriminativity, which can be represented as probability scores. Given these scores, we also propose several feature fusion and selection schemes to integrate their strengths. The classification of the whole image is conducted by aggregating the results from multiple cues of all cells. We apply our algorithm on differentiating adenocarcinoma and squamous carcinoma, i.e., two types of lung cancers, using a large dataset containing thousands of lung microscopic tissue images. It achieves 90.3% accuracy by hashing and retrieving multiple cues of half-million cells.

  5. [Monomorphic post-transplant T-lymphoproliferative disorder after autologous stem cell transplantation for multiple myeloma].

    Science.gov (United States)

    Ishikawa, Tetsuya; Shimizu, Hiroaki; Takei, Toshifumi; Koya, Hiroko; Iriuchishima, Hirono; Hosiho, Takumi; Hirato, Junko; Kojima, Masaru; Handa, Hiroshi; Nojima, Yoshihisa; Murakami, Hirokazu

    2016-01-01

    We report a rare case of T cell type monomorphic post-transplant lymphoproliferative disorders (PTLD) after autologous stem cell transplantation. A 53-year-old man with multiple myeloma received autologous stem cell transplantation and achieved a very good partial response. Nine months later, he developed a high fever and consciousness disturbance, and had multiple swollen lymph nodes and a high titer of Epstein-Barr (EB) virus DNA in his peripheral blood. Neither CT nor MRI of the brain revealed any abnormalities. Cerebrospinal fluid contained no malignant cells, but the EB virus DNA titer was high. Lymph node biopsy revealed T cell type monomorphic PTLD. Soon after high-dose treatment with methotrexate and cytosine arabinoside, the high fever and consciousness disturbance subsided, and the lymph node swelling and EB virus DNA disappeared. Given the efficacy of chemotherapy in this case, we concluded that the consciousness disturbance had been induced by central nervous system involvement of monomorphic PTLD.

  6. Concise Review: Methods and Cell Types Used to Generate Down Syndrome Induced Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Youssef Hibaoui

    2015-04-01

    Full Text Available Down syndrome (DS, trisomy 21, is the most common viable chromosomal disorder, with an incidence of 1 in 800 live births. Its phenotypic characteristics include intellectual impairment and several other developmental abnormalities, for the majority of which the pathogenetic mechanisms remain unknown. Several models have been used to investigate the mechanisms by which the extra copy of chromosome 21 leads to the DS phenotype. In the last five years, several laboratories have been successful in reprogramming patient cells carrying the trisomy 21 anomaly into induced pluripotent stem cells, i.e., T21-iPSCs. In this review, we summarize the different T21-iPSCs that have been generated with a particular interest in the technical procedures and the somatic cell types used for the reprogramming.

  7. Lichen planopilaris after imiquimod 5% cream for multiple BCC in basal cell naevus syndrome.

    Science.gov (United States)

    Drummond, Alessandra; Pichler, Janine; Argenziano, Giuseppe; Zalaudek, Iris; Longo, Caterina; Lallas, Aimilios; Piana, Simonetta; Moscarella, Elvira

    2015-11-01

    Basal cell naevus syndrome is an inherited autosomal dominant genetic disorder characterised by multiple basal cell carcinomas (BCC), skeletal, neurological and opthalmological abnormalities. The treatment of choice of the often multiple and large BCC consists of a combined approach including surgery, liquid nitrogen and other topical treatment modalities. Imiquimod 5% cream is an immune-response-modifying drug with antiviral and anti-tumour activity. Recent reports have associated the immune-stimulant properties of imiquimod with the exacerbation of several autoimmune skin diseases, such as eczema, psoriasis, vitiligo and lichenoid dermatitis. Here we report a patient with basal cell naevus syndrome who developed a lichen planopilaris on the same site of the scalp, which had been previously treated with two cycles of imiquimod for multiple BCC.

  8. Direct Reprogramming of Human Primordial Germ Cells into Induced Pluripotent Stem Cells: Efficient Generation of Genetically Engineered Germ Cells.

    Science.gov (United States)

    Bazley, Faith A; Liu, Cyndi F; Yuan, Xuan; Hao, Haiping; All, Angelo H; De Los Angeles, Alejandro; Zambidis, Elias T; Gearhart, John D; Kerr, Candace L

    2015-11-15

    Primordial germ cells (PGCs) share many properties with embryonic stem cells (ESCs) and innately express several key pluripotency-controlling factors, including OCT4, NANOG, and LIN28. Therefore, PGCs may provide a simple and efficient model for studying somatic cell reprogramming to induced pluripotent stem cells (iPSCs), especially in determining the regulatory mechanisms that fundamentally define pluripotency. Here, we report a novel model of PGC reprogramming to generate iPSCs via transfection with SOX2 and OCT4 using integrative lentiviral. We also show the feasibility of using nonintegrative approaches for generating iPSC from PGCs using only these two factors. We show that human PGCs express endogenous levels of KLF4 and C-MYC protein at levels similar to embryonic germ cells (EGCs) but lower levels of SOX2 and OCT4. Transfection with both SOX2 and OCT4 together was required to induce PGCs to a pluripotent state at an efficiency of 1.71%, and the further addition of C-MYC increased the efficiency to 2.33%. Immunohistochemical analyses of the SO-derived PGC-iPSCs revealed that these cells were more similar to ESCs than EGCs regarding both colony morphology and molecular characterization. Although leukemia inhibitory factor (LIF) was not required for the generation of PGC-iPSCs like EGCs, the presence of LIF combined with ectopic exposure to C-MYC yielded higher efficiencies. Additionally, the SO-derived PGC-iPSCs exhibited differentiation into representative cell types from all three germ layers in vitro and successfully formed teratomas in vivo. Several lines were generated that were karyotypically stable for up to 24 subcultures. Their derivation efficiency and survival in culture significantly supersedes that of EGCs, demonstrating their utility as a powerful model for studying factors regulating pluripotency in future studies.

  9. POOR HEMOPOIETIC STEM CELL MOBILIZERS IN MULTIPLE MYELOMA : A SINGLE INSTITUTION EXPERIENCE

    Directory of Open Access Journals (Sweden)

    Guillermo Jose Ruiz-Delgado

    2010-06-01

    Full Text Available In a single institution, in a group of 28 myeloma patients deemed eligible for autologous transplant, stem cell mobilization was attempted using filgrastim: 26 individuals were given 31 autografts employing 1-4 (median three apheresis sessions, to obtain a target stem cell dose of 1 x 106 CD34 viable cells / Kg of the recipient. The median number of grafted CD34 cells was 7.56 x 106  / Kg of the recipient; the range being 0.92 to 14.8.  By defining as poor mobilizers individuals in which a cell collection of 1 x 106 CD34 viable cells / Kg was better (80% at 80 months than those grafted with < 1 x 106 CD34 viable cells / Kg (67% at 76 months. Methods to improve stem cell mobilization are needed and may result in obtaining better results when autografting multiple myeloma patients.

  10. A Model of Generating Visual Place Cells Based on Environment Perception and Similar Measure

    Directory of Open Access Journals (Sweden)

    Yang Zhou

    2016-01-01

    Full Text Available It is an important content to generate visual place cells (VPCs in the field of bioinspired navigation. By analyzing the firing characteristic of biological place cells and the existing methods for generating VPCs, a model of generating visual place cells based on environment perception and similar measure is abstracted in this paper. VPCs’ generation process is divided into three phases, including environment perception, similar measure, and recruiting of a new place cell. According to this process, a specific method for generating VPCs is presented. External reference landmarks are obtained based on local invariant characteristics of image and a similar measure function is designed based on Euclidean distance and Gaussian function. Simulation validates the proposed method is available. The firing characteristic of the generated VPCs is similar to that of biological place cells, and VPCs’ firing fields can be adjusted flexibly by changing the adjustment factor of firing field (AFFF and firing rate’s threshold (FRT.

  11. Hedgehog signaling maintains a tumor stem cell compartment in multiple myeloma.

    Science.gov (United States)

    Peacock, Craig D; Wang, Qiuju; Gesell, Gregory S; Corcoran-Schwartz, Ian M; Jones, Evan; Kim, Jynho; Devereux, Wendy L; Rhodes, Jonathan T; Huff, Carol A; Beachy, Philip A; Watkins, D Neil; Matsui, William

    2007-03-01

    The cancer stem cell hypothesis suggests that malignant growth depends on a subset of tumor cells with stem cell-like properties of self-renewal. Because hedgehog (Hh) signaling regulates progenitor cell fate in normal development and homeostasis, aberrant pathway activation might be involved in the maintenance of such a population in cancer. Indeed, mutational activation of the Hh pathway is associated with medulloblastoma and basal cell carcinoma; pathway activity is also critical for growth of other tumors lacking such mutations, although the mechanism of pathway activation is poorly understood. Here we study the role and mechanism of Hh pathway activation in multiple myeloma (MM), a malignancy with a well defined stem cell compartment. In this model, rare malignant progenitors capable of clonal expansion resemble B cells, whereas the much larger tumor cell population manifests a differentiated plasma cell phenotype that pathologically defines the disease. We show that the subset of MM cells that manifests Hh pathway activity is markedly concentrated within the tumor stem cell compartment. The Hh ligand promotes expansion of MM stem cells without differentiation, whereas the Hh pathway blockade, while having little or no effect on malignant plasma cell growth, markedly inhibits clonal expansion accompanied by terminal differentiation of purified MM stem cells. These data reveal that Hh pathway activation is heterogeneous across the spectrum of MM tumor stem cells and their more differentiated progeny. The potential existence of similar relationships in other adult cancers may have important biologic and clinical implications for the study of aberrant Hh signaling.

  12. Efficient Generation of β-Globin-Expressing Erythroid Cells Using Stromal Cell-Derived Induced Pluripotent Stem Cells from Patients with Sickle Cell Disease.

    Science.gov (United States)

    Uchida, Naoya; Haro-Mora, Juan J; Fujita, Atsushi; Lee, Duck-Yeon; Winkler, Thomas; Hsieh, Matthew M; Tisdale, John F

    2017-03-01

    Human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells represent an ideal source for in vitro modeling of erythropoiesis and a potential alternative source for red blood cell transfusions. However, iPS cell-derived erythroid cells predominantly produce ε- and γ-globin without β-globin production. We recently demonstrated that ES cell-derived sacs (ES sacs), known to express hemangioblast markers, allow for efficient erythroid cell generation with β-globin production. In this study, we generated several iPS cell lines derived from bone marrow stromal cells (MSCs) and peripheral blood erythroid progenitors (EPs) from sickle cell disease patients, and evaluated hematopoietic stem/progenitor cell (HSPC) generation after iPS sac induction as well as subsequent erythroid differentiation. MSC-derived iPS sacs yielded greater amounts of immature hematopoietic progenitors (VEGFR2 + GPA-), definitive HSPCs (CD34 + CD45+), and megakaryoerythroid progenitors (GPA + CD41a+), as compared to EP-derived iPS sacs. Erythroid differentiation from MSC-derived iPS sacs resulted in greater amounts of erythroid cells (GPA+) and higher β-globin (and βS-globin) expression, comparable to ES sac-derived cells. These data demonstrate that human MSC-derived iPS sacs allow for more efficient erythroid cell generation with higher β-globin production, likely due to heightened emergence of immature progenitors. Our findings should be important for iPS cell-derived erythroid cell generation. Stem Cells 2017;35:586-596.

  13. Combining multiple models to generate consensus: Application to radiation-induced pneumonitis prediction

    Science.gov (United States)

    Das, Shiva K.; Chen, Shifeng; Deasy, Joseph O.; Zhou, Sumin; Yin, Fang-Fang; Marks, Lawrence B.

    2008-01-01

    The fusion of predictions from disparate models has been used in several fields to obtain a more realistic and robust estimate of the “ground truth” by allowing the models to reinforce each other when consensus exists, or, conversely, negate each other when there is no consensus. Fusion has been shown to be most effective when the models have some complementary strengths arising from different approaches. In this work, we fuse the results from four common but methodologically different nonlinear multivariate models (Decision Trees, Neural Networks, Support Vector Machines, Self-Organizing Maps) that were trained to predict radiation-induced pneumonitis risk on a database of 219 lung cancer patients treated with radiotherapy (34 with Grade 2+ postradiotherapy pneumonitis). Each model independently incorporated a small number of features from the available set of dose and nondose patient variables to predict pneumonitis; no two models had all features in common. Fusion was achieved by simple averaging of the predictions for each patient from all four models. Since a model’s prediction for a patient can be dependent on the patient training set used to build the model, the average of several different predictions from each model was used in the fusion (predictions were made by repeatedly testing each patient with a model built from different cross-validation training sets that excluded the patient being tested). The area under the receiver operating characteristics curve for the fused cross-validated results was 0.79, with lower variance than the individual component models. From the fusion, five features were extracted as the consensus among all four models in predicting radiation pneumonitis. Arranged in order of importance, the features are (1) chemotherapy; (2) equivalent uniform dose (EUD) for exponent a=1.2 to 3; (3) EUD for a=0.5 to 1.2, lung volume receiving >20–30 Gy; (4) female sex; and (5) squamous cell histology. To facilitate ease of interpretation

  14. Combining multiple models to generate consensus: Application to radiation-induced pneumonitis prediction

    Energy Technology Data Exchange (ETDEWEB)

    Das, Shiva K.; Chen Shifeng; Deasy, Joseph O.; Zhou Sumin; Yin Fangfang; Marks, Lawrence B. [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Radiation Oncology, Washington University School of Medicine, St. Louis, Missouri 63110 (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27710 (United States); Department of Radiation Oncology, University of North Carolina School of Medicine, Chapel Hill, North Carolina 27599 (United States)

    2008-11-15

    The fusion of predictions from disparate models has been used in several fields to obtain a more realistic and robust estimate of the ''ground truth'' by allowing the models to reinforce each other when consensus exists, or, conversely, negate each other when there is no consensus. Fusion has been shown to be most effective when the models have some complementary strengths arising from different approaches. In this work, we fuse the results from four common but methodologically different nonlinear multivariate models (Decision Trees, Neural Networks, Support Vector Machines, Self-Organizing Maps) that were trained to predict radiation-induced pneumonitis risk on a database of 219 lung cancer patients treated with radiotherapy (34 with Grade 2+ postradiotherapy pneumonitis). Each model independently incorporated a small number of features from the available set of dose and nondose patient variables to predict pneumonitis; no two models had all features in common. Fusion was achieved by simple averaging of the predictions for each patient from all four models. Since a model's prediction for a patient can be dependent on the patient training set used to build the model, the average of several different predictions from each model was used in the fusion (predictions were made by repeatedly testing each patient with a model built from different cross-validation training sets that excluded the patient being tested). The area under the receiver operating characteristics curve for the fused cross-validated results was 0.79, with lower variance than the individual component models. From the fusion, five features were extracted as the consensus among all four models in predicting radiation pneumonitis. Arranged in order of importance, the features are (1) chemotherapy; (2) equivalent uniform dose (EUD) for exponent a=1.2 to 3; (3) EUD for a=0.5 to 1.2, lung volume receiving >20-30 Gy; (4) female sex; and (5) squamous cell histology. To facilitate

  15. In-channel printing-device opening assay for micropatterning multiple cells and gene analysis.

    Science.gov (United States)

    Zhou, Hao; Zhao, Liang; Zhang, Xueji

    2015-02-17

    Herein we report an easy but versatile method for patterning different cells on a single substrate by using a microfluidic approach that allows not only spatial and temporal control of multiple microenvironments but also retrieval of specific treated cells to profile their expressed genetic information at around 10-cell resolution. By taking advantages of increased surface area of gold nanoparticles on a poly(dimethylsiloxane) (PDMS) coated substrate, cell adhesive-promotive protein, human fibronectin (hFN) can be significantly accumulated on designed regions where cells can recognize the protein and spread out. Moreover, the whole device can be easily opened by hand without any loss of patterned cells which could be retrieved by mouth-pipet. Consequently, we demonstrate the possibility of analyzing the difference of gene expression patterns between wild type MCF-7 cell and MCF/Adr (drug-resistant cell line) from less than 400 cells in total for a single comprehensive assay, including parallel experiments, controls, and multiple dose treatments. Certain genes, especially the P-glycoprotein coding gene (ABCB1), show high expression level in resistant cells compared with the wild type, suggesting a possible pathway that may contribute to the antidrug mechanism.

  16. In Vitro Generation of Functional Liver Organoid-Like Structures Using Adult Human Cells

    NARCIS (Netherlands)

    Ramachandran, S.D.; Schirmer, K.; Munst, B.; Heinz, S.; Ghafoory, S.; Wolfl, S.; Simon-Keller, K.; Marx, A.; Oie, C.I.; Ebert, M.P.; Walles, H.; Braspenning, J.C.; Breitkopf-Heinlein, K.

    2015-01-01

    In this study we used differentiated adult human upcyte(R) cells for the in vitro generation of liver organoids. Upcyte(R) cells are genetically engineered cell strains derived from primary human cells by lenti-viral transduction of genes or gene combinations inducing transient proliferation capacit

  17. Generation of human-induced pluripotent stem cells.

    Science.gov (United States)

    Park, In-Hyun; Lerou, Paul H; Zhao, Rui; Huo, Hongguang; Daley, George Q

    2008-01-01

    Pluripotent cells, such as embryonic stem cells, are invaluable tools for research and can potentially serve as a source of cell- and tissue-replacement therapy. Rejection after transplantation of cells and tissue derived from embryonic stem cells is a significant obstacle to their clinical use. Recently, human somatic cells have been reprogrammed directly to pluripotency by ectopic expression of four transcription factors (Oct4, Sox2, Klf4 and Myc) to yield induced pluripotent stem (iPS) cells. Human iPS cells are a potential source of patient-specific pluripotent stem cells that would bypass immune rejection. iPS cells can also be used to study diseases for which there are no adequate human in vitro or animal models. In this protocol, we describe how to establish primary human fibroblasts lines and how to derive iPS cells by retroviral transduction of reprogramming factors. Overall, it takes 2 months to complete reprogramming human primary fibroblasts starting from biopsy.

  18. Multiple nephron-sparing procedures in solitary kidney with recurrent, metachronous, nonfamilial renal cell carcinoma.

    Science.gov (United States)

    Nosnik, Israel P; Mouraviev, Vladimir; Nelson, Rendon; Polascik, Thomas J

    2006-12-01

    Patients with metachronous bilateral renal cell carcinoma pose a significant challenge given the high mortality of renal cell carcinoma and the poor quality of life should dialysis become necessary. In addition, patients may be subject to morbidity due to potential multiple treatments of the multifocal renal tumors. We present the case of a 71-year-old woman with multifocal, bilateral clear cell carcinoma who maintained a minimal change in serum creatinine after undergoing unilateral radical nephrectomy, subsequent percutaneous radiofrequency ablation, percutaneous cryoablation, laparoscopic cryoablation, and open partial nephrectomy for recurrent renal cell carcinoma in a solitary kidney.

  19. Adult T-cell leukemia/lymphoma presenting multiple lymphomatous polyposis

    Institute of Scientific and Technical Information of China (English)

    Akira Hokama; Nobuyuki Takasu; Jiro Fujita; Takeaki Tomoyose; Yu-ichi Yamamoto; Takako Watanabe; Tetsuo Hirata; Fukunori Kinjo; Seiya Kato; Koichi Ohshima; Hiroshi Uezato

    2008-01-01

    Multiple lymphomatous polyposis (HLP) is an unusual form of non-Hodgkin's lymphoma characterized by polyps throughout the gastrointestinal tract. It has been reported that most MLP are observed in cases with mantle cell lymphoma of B-cell type. We herein present a case of a 66-year-old man with adult T-cell leukemia/lymphoma (ATLL). Colonoscopy revealed MLP throughout the colon and histopathological findings of ATLL cell infiltration. The patient died despite combination of chemotherapy. The literature of manifestations of colonic involvement of ATLL is reviewed and the importance of endoscopic evaluation to differentiate ATLL intestinal lesions from opportunistic infectious enterocolitis is discussed.

  20. Next generation sequencing (NGS) database for tandem repeats with multiple pattern 2°-shaft multicore string matching.

    Science.gov (United States)

    Someswara Rao, Chinta; Raju, S Viswanadha

    2016-03-01

    Next generation sequencing (NGS) technologies have been rapidly applied in biomedical and biological research in recent years. To provide the comprehensive NGS resource for the research, in this paper , we have considered 10 loci/codi/repeats TAGA, TCAT, GAAT, AGAT, AGAA, GATA, TATC, CTTT, TCTG and TCTA. Then we developed the NGS Tandem Repeat Database (TandemRepeatDB) for all the chromosomes of Homo sapiens, Callithrix jacchus, Chlorocebus sabaeus, Gorilla gorilla, Macaca fascicularis, Macaca mulatta, Nomascus leucogenys, Pan troglodytes, Papio anubis and Pongo abelii genome data sets for all those locis. We find the successive occurence frequency for all the above 10 SSR (simple sequence repeats) in the above genome data sets on a chromosome-by-chromosome basis with multiple pattern 2° shaft multicore string matching.

  1. Next generation sequencing (NGS database for tandem repeats with multiple pattern 2°-shaft multicore string matching

    Directory of Open Access Journals (Sweden)

    Chinta Someswara Rao

    2016-03-01

    Full Text Available Next generation sequencing (NGS technologies have been rapidly applied in biomedical and biological research in recent years. To provide the comprehensive NGS resource for the research, in this paper , we have considered 10 loci/codi/repeats TAGA, TCAT, GAAT, AGAT, AGAA, GATA, TATC, CTTT, TCTG and TCTA. Then we developed the NGS Tandem Repeat Database (TandemRepeatDB for all the chromosomes of Homo sapiens, Callithrix jacchus, Chlorocebus sabaeus, Gorilla gorilla, Macaca fascicularis, Macaca mulatta, Nomascus leucogenys, Pan troglodytes, Papio anubis and Pongo abelii genome data sets for all those locis. We find the successive occurence frequency for all the above 10 SSR (simple sequence repeats in the above genome data sets on a chromosome-by-chromosome basis with multiple pattern 2° shaft multicore string matching.

  2. Next generation sequencing (NGS) database for tandem repeats with multiple pattern 2°-shaft multicore string matching

    Science.gov (United States)

    Someswara Rao, Chinta; Raju, S. Viswanadha

    2016-01-01

    Next generation sequencing (NGS) technologies have been rapidly applied in biomedical and biological research in recent years. To provide the comprehensive NGS resource for the research, in this paper , we have considered 10 loci/codi/repeats TAGA, TCAT, GAAT, AGAT, AGAA, GATA, TATC, CTTT, TCTG and TCTA. Then we developed the NGS Tandem Repeat Database (TandemRepeatDB) for all the chromosomes of Homo sapiens, Callithrix jacchus, Chlorocebus sabaeus, Gorilla gorilla, Macaca fascicularis, Macaca mulatta, Nomascus leucogenys, Pan troglodytes, Papio anubis and Pongo abelii genome data sets for all those locis. We find the successive occurence frequency for all the above 10 SSR (simple sequence repeats) in the above genome data sets on a chromosome-by-chromosome basis with multiple pattern 2° shaft multicore string matching. PMID:26981434

  3. Generation of GHZ entangled states of photons in multiple cavities via a superconucting qubit or an atom through resonant interaction

    CERN Document Server

    Yang, Chui-Ping

    2012-01-01

    We propose a method to generate a GHZ entangled state of n photons in n microwave cavities (or resonators) via resonant interaction to a single superconducting qubit. By performing local operations on a qubit (e.g., a solid-state qubit, an atom, etc.) placed in each cavity, the created GHZ states of n photons can be transferred to qubits for storage. The proposed scheme greatly reduces effect of decoherence since only resonant qubit-cavity interaction and resonant qubit-pulse interaction are involved, and no measurement is required. In addition, we show that the method can be applied to create a GHZ state of photons in multiple cavities via an atom through resonant interaction with no measurement needed.

  4. Multiple target implementation for a doubly fed induction generator based on direct power control under unbalanced and distorted grid voltage

    Institute of Scientific and Technical Information of China (English)

    Heng NIAN; Yi-peng SONG

    2015-01-01

    This paper presents a multiple target implementation technique for a doubly fed induction generator (DFIG) under unbalanced and distorted grid voltage based on direct power control (DPC). Based on the mathematical model of DFIG under unbalanced and distorted voltage, the proportional and integral (PI) regulator is adopted to regulate the DFIG average active and reactive powers, while the vector PI (VPI) resonant regulator is used to achieve three alternative control targets: (1) balanced and sinusoidal stator current; (2) smooth instantaneous stator active and reactive powers; (3) smooth electromagnetic torque and instantaneous stator reactive power. The major advantage of the proposed control strategy over the conventional method is that neither negative and harmonic sequence decomposition of grid voltage nor complicated control reference calculation is required. The insensitivity of the proposed control strategy to DFIG parameter deviation is analyzed. Finally, the DFIG experimental system is developed to validate the availability of the proposed DPC strategy under unbalanced and distorted grid voltage.

  5. Killing multiple myeloma cells with the small molecule 3-bromopyruvate: implications for therapy.

    Science.gov (United States)

    Majkowska-Skrobek, Grażyna; Augustyniak, Daria; Lis, Paweł; Bartkowiak, Anna; Gonchar, Mykhailo; Ko, Young H; Pedersen, Peter L; Goffeau, Andre; Ułaszewski, Stanisław

    2014-07-01

    The small molecule 3-bromopyruvate (3-BP), which has emerged recently as the first member of a new class of potent anticancer agents, was tested for its capacity to kill multiple myeloma (MM) cancer cells. Human MM cells (RPMI 8226) begin to lose viability significantly within 8 h of incubation in the presence of 3-BP. The Km (0.3 mmol/l) for intracellular accumulation of 3-BP in MM cells is 24 times lower than that in control cells (7.2 mmol/l). Therefore, the uptake of 3-BP by MM cells is significantly higher than that by peripheral blood mononuclear cells. Further, the IC50 values for human MM cells and control peripheral blood mononuclear cells are 24 and 58 µmol/l, respectively. Therefore, specificity and selectivity of 3-BP toward MM cancer cells are evident on the basis of the above. In MM cells the transcription levels of the gene encoding the monocarboxylate transporter MCT1 is significantly amplified compared with control cells. The level of intracellular ATP in MM cells decreases by over 90% within 1 h after addition of 100 µmol/l 3-BP. The cytotoxicity of 3-BP, exemplified by a marked decrease in viability of MM cells, is potentiated by the inhibitor of glutathione synthesis buthionine sulfoximine. In addition, the lack of mutagenicity and its superior capacity relative to Glivec to kill MM cancer cells are presented in this study.

  6. Imperatorin Suppresses Degranulation and Eicosanoid Generation in Activated Bone Marrow-Derived Mast Cells.

    Science.gov (United States)

    Jeong, Kyu-Tae; Lee, Eujin; Park, Na-Young; Kim, Sun-Gun; Park, Hyo-Hyun; Lee, Jiean; Lee, Youn Ju; Lee, Eunkyung

    2015-09-01

    Imperatorin has been known to exert many biological functions including anti-inflammatory activity. In this study, we investigated the inhibitory effects of imperatorin on the production of inflammatory mediators in mouse bone marrow-derived mast cells (BMMC). Imperatorin inhibited degranulation and the generation of eicosanoids (leukotriene C4 (LTC4) and prostaglandin D2 (PGD2)) in IgE/antigen (Ag)-stimulated BMMC. To elucidate the molecular mechanism involved in this process, we investigated the effect of imperatorin on intracellular signaling in BMMC. Biochemical analyses of the IgE/Ag-mediated signaling pathway demonstrated that imperatorin dramatically attenuated degranulation and the production of 5-lipoxygenase-dependent LTC4 and cyclooxygenase-2-dependent PGD2 through the inhibition of intracellular calcium influx/phospholipase Cγ1, cytosolic phospholipase A2/mitogen-activated protein kinases and/or nuclear factor-κB pathways in BMMC. These results suggest that the effects of imperatorin on inhibition of degranulation and eicosanoid generation through the suppression of multiple steps of IgE/Ag-mediated signaling pathways would be beneficial for the prevention of allergic inflammation.

  7. Generation of mast cells from mouse fetus: analysis of differentiation and functionality, and transcriptome profiling using next generation sequencer.

    Directory of Open Access Journals (Sweden)

    Nobuyuki Fukuishi

    Full Text Available While gene knockout technology can reveal the roles of proteins in cellular functions, including in mast cells, fetal death due to gene manipulation frequently interrupts experimental analysis. We generated mast cells from mouse fetal liver (FLMC, and compared the fundamental functions of FLMC with those of bone marrow-derived mouse mast cells (BMMC. Under electron microscopy, numerous small and electron-dense granules were observed in FLMC. In FLMC, the expression levels of a subunit of the FcεRI receptor and degranulation by IgE cross-linking were comparable with BMMC. By flow cytometry we observed surface expression of c-Kit prior to that of FcεRI on FLMC, although on BMMC the expression of c-Kit came after FcεRI. The surface expression levels of Sca-1 and c-Kit, a marker of putative mast cell precursors, were slightly different between bone marrow cells and fetal liver cells, suggesting that differentiation stage or cell type are not necessarily equivalent between both lineages. Moreover, this indicates that phenotypically similar mast cells may not have undergone an identical process of differentiation. By comprehensive analysis using the next generation sequencer, the same frequency of gene expression was observed for 98.6% of all transcripts in both cell types. These results indicate that FLMC could represent a new and useful tool for exploring mast cell differentiation, and may help to elucidate the roles of individual proteins in the function of mast cells where gene manipulation can induce embryonic lethality in the mid to late stages of pregnancy.

  8. Functional Neurons Generated from T Cell-Derived Induced Pluripotent Stem Cells for Neurological Disease Modeling

    Directory of Open Access Journals (Sweden)

    Takuya Matsumoto

    2016-03-01

    Full Text Available Modeling of neurological diseases using induced pluripotent stem cells (iPSCs derived from the somatic cells of patients has provided a means of elucidating pathogenic mechanisms and performing drug screening. T cells are an ideal source of patient-specific iPSCs because they can be easily obtained from samples. Recent studies indicated that iPSCs retain an epigenetic memory relating to their cell of origin that restricts their differentiation potential. The classical method of differentiation via embryoid body formation was not suitable for T cell-derived iPSCs (TiPSCs. We developed a neurosphere-based robust differentiation protocol, which enabled TiPSCs to differentiate into functional neurons, despite differences in global gene expression between TiPSCs and adult human dermal fibroblast-derived iPSCs. Furthermore, neurons derived from TiPSCs generated from a juvenile patient with Parkinson's disease exhibited several Parkinson's disease phenotypes. Therefore, we conclude that TiPSCs are a useful tool for modeling neurological diseases.

  9. Effect of Natalizumab on Circulating CD4(+) T-Cells in Multiple Sclerosis

    DEFF Research Database (Denmark)

    Börnsen, Lars; Christensen, Jeppe Romme; Ratzer, Rikke;

    2012-01-01

    In multiple sclerosis (MS), treatment with the monoclonal antibody natalizumab effectively reduces the formation of acute lesions in the central nervous system (CNS). Natalizumab binds the integrin very late antigen (VLA)-4, expressed on the surface of immune cells, and inhibits VLA-4 dependent......-cells due to reduced extravasation of activated and pro-inflammatory T-cells or due to induction of VLA-4 mediated co-stimulatory signals by natalizumab. In this study we examined how natalizumab treatment altered the distribution of effector and memory T-cell subsets in the blood compartment and if T......(HIGH) T-cells, in blood, and natalizumab decreased the expression of CD134 on MBP-reactive CD26(HIGH)CD4(+) T-cells in vitro. Otherwise CD4(+) T-cells from natalizumab-treated and untreated MS patients showed similar responses to MBP. In conclusion natalizumab treatment selectively increased...

  10. Determination of cell survival after irradiation via clonogenic assay versus multiple MTT Assay - A comparative study

    Directory of Open Access Journals (Sweden)

    Buch Karl

    2012-01-01

    Full Text Available Abstract For studying proliferation and determination of survival of cancer cells after irradiation, the multiple MTT assay, based on the reduction of a yellow water soluble tetrazolium salt to a purple water insoluble formazan dye by living cells was modified from a single-point towards a proliferation assay. This assay can be performed with a large number of samples in short time using multi-well-plates, assays can be performed semi-automatically with a microplate reader. Survival, the calculated parameter in this assay, is determined mathematically. Exponential growth in both control and irradiated groups was proven as the underlying basis of the applicability of the multiple MTT assay. The equivalence to a clonogenic survival assay with its disadvantages such as time consumption was proven in two setups including plating of cells before and after irradiation. Three cell lines (A 549, LN 229 and F 98 were included in the experiment to study its principal and general applicability.

  11. Donor-Derived Smoldering Multiple Myeloma following a Hematopoietic Cell Transplantation for AML

    Science.gov (United States)

    Fiala, Mark; Slade, Michael; Westervelt, Peter

    2017-01-01

    Posttransplant Lymphoproliferative Disorder (PTLD) is one of the most common malignancies complicating solid organ transplantation. In contrast, PTLD accounts for a minority of secondary cancers following allogeneic hematopoietic cell transplantation (HCT). Here we report on a 61-year-old woman who received an ABO-mismatched, HLA-matched unrelated donor hematopoietic cell transplantation from a presumably healthy donor for a diagnosis of acute myeloid leukemia (AML). Eighteen months following her transplant, she developed a monoclonal gammopathy. Bone marrow studies revealed 10% plasma cells, but the patient lacked clinical defining features of multiple myeloma (MM); thus a diagnosis of smoldering multiple myeloma (SMM) was established. Cytogenetic and molecular studies of the bone marrow confirmed the plasma cells were donor-derived. The donor lacks a diagnosis of monoclonal gammopathy of undetermined significance, SMM, or MM. PMID:28316846

  12. Donor-Derived Smoldering Multiple Myeloma following a Hematopoietic Cell Transplantation for AML

    Directory of Open Access Journals (Sweden)

    Bita Fakhri

    2017-01-01

    Full Text Available Posttransplant Lymphoproliferative Disorder (PTLD is one of the most common malignancies complicating solid organ transplantation. In contrast, PTLD accounts for a minority of secondary cancers following allogeneic hematopoietic cell transplantation (HCT. Here we report on a 61-year-old woman who received an ABO-mismatched, HLA-matched unrelated donor hematopoietic cell transplantation from a presumably healthy donor for a diagnosis of acute myeloid leukemia (AML. Eighteen months following her transplant, she developed a monoclonal gammopathy. Bone marrow studies revealed 10% plasma cells, but the patient lacked clinical defining features of multiple myeloma (MM; thus a diagnosis of smoldering multiple myeloma (SMM was established. Cytogenetic and molecular studies of the bone marrow confirmed the plasma cells were donor-derived. The donor lacks a diagnosis of monoclonal gammopathy of undetermined significance, SMM, or MM.

  13. Oxygen-Generating Nanofiber Cell Scaffolds with Antimicrobial Properties

    NARCIS (Netherlands)

    Wang, Junping; Zhu, Yizhou; Bawa, Harinder K.; Ng, Geoffrey; Wu, Yong; Libera, Matthew; van der Mei, H. C.; Busscher, H. J.; Yu, Xiaojun

    2011-01-01

    Many next-generation biomaterials will need ability to not only promote healthy tissue integration but to simultaneously resist bacterial colonization resulting biomaterials associated infection. For this purpose, antimicrobial nanofibers of (polycapro-lactone(PCL) were fabricated by incorporating c

  14. Complex heterogeneous tissue constructs containing multiple cell types prepared by inkjet printing technology.

    Science.gov (United States)

    Xu, Tao; Zhao, Weixin; Zhu, Jian-Ming; Albanna, Mohammad Z; Yoo, James J; Atala, Anthony

    2013-01-01

    This study was designed to develop a versatile method for fabricating complex and heterogeneous three-dimensional (3D) tissue constructs using simultaneous ink-jetting of multiple cell types. Human amniotic fluid-derived stem cells (hAFSCs), canine smooth muscle cells (dSMCs), and bovine aortic endothelial cells (bECs), were separately mixed with ionic cross-linker calcium chloride (CaCl(2)), loaded into separate ink cartridges and printed using a modified thermal inkjet printer. The three cell types were delivered layer-by-layer to pre-determined locations in a sodium alginate-collagen composite located in a chamber under the printer. The reaction between CaCl(2) and sodium alginate resulted in a rapid formation of a solid composite gel and the printed cells were anchored in designated areas within the gel. The printing process was repeated for several cycles leading to a complex 3D multi-cell hybrid construct. The biological functions of the 3D printed constructs were evaluated in vitro and in vivo. Each of the printed cell types maintained their viability and normal proliferation rates, phenotypic expression, and physiological functions within the heterogeneous constructs. The bioprinted constructs were able to survive and mature into functional tissues with adequate vascularization in vivo. These findings demonstrate the feasibility of fabricating complex heterogeneous tissue constructs containing multiple cell types using inkjet printing technology.

  15. Pathogenic CD8 T cells in Multiple Sclerosis and its experimental models

    Directory of Open Access Journals (Sweden)

    Eric S. Huseby

    2012-03-01

    Full Text Available A growing body of evidence suggests that autoreactive CD8 T cells contribute to the disease process in Multiple Sclerosis (MS. Lymphocytes in MS plaques are biased toward the CD8 lineage, and MS patients harbor CD8 T cells specific for multiple central nervous system (CNS antigens. Currently, there are relatively few experimental model systems available to study these pathogenic CD8 T cells in vivo. However, the few studies that have been done characterizing the mechanisms used by CD8 T cells to induce CNS autoimmunity indicate that several of the paradigms of how CD4 T cells mediate CNS autoimmunity do not hold true for CD8 T cells or for patients with MS. Thus, myelin-specific CD4 T cells are likely to be one of several important mechanisms that drive CNS disease in MS patients. The focus of this review is to highlight the current models of pathogenic CNS-reactive CD8 T cells and the molecular mechanisms these lymphocytes use when causing CNS inflammation and damage. Understanding how CNS-reactive CD8 T cells escape tolerance induction and induce CNS autoimmunity is critical to our ability to propose and test new therapies for MS.

  16. Digestion of algal biomass for electricity generation in microbial fuel cells.

    Science.gov (United States)

    Nishio, Koichi; Hashimoto, Kazuhito; Watanabe, Kazuya

    2013-01-01

    Algal biomass serves as a fuel for electricity generation in microbial fuel cells. This study constructed a model consortium comprised of an alga-digesting Lactobacillus and an iron-reducing Geobacter for electricity generation from photo-grown Clamydomonas cells. Total power-conversion efficiency (from Light to electricity) was estimated to be 0.47%.

  17. Label-free morphology-based prediction of multiple differentiation potentials of human mesenchymal stem cells for early evaluation of intact cells.

    Directory of Open Access Journals (Sweden)

    Hiroto Sasaki

    Full Text Available Precise quantification of cellular potential of stem cells, such as human bone marrow-derived mesenchymal stem cells (hBMSCs, is important for achieving stable and effective outcomes in clinical stem cell therapy. Here, we report a method for image-based prediction of the multiple differentiation potentials of hBMSCs. This method has four major advantages: (1 the cells used for potential prediction are fully intact, and therefore directly usable for clinical applications; (2 predictions of potentials are generated before differentiation cultures are initiated; (3 prediction of multiple potentials can be provided simultaneously for each sample; and (4 predictions of potentials yield quantitative values that correlate strongly with the experimental data. Our results show that the collapse of hBMSC differentiation potentials, triggered by in vitro expansion, can be quantitatively predicted far in advance by predicting multiple potentials, multi-lineage differentiation potentials (osteogenic, adipogenic, and chondrogenic and population doubling potential using morphological features apparent during the first 4 days of expansion culture. In order to understand how such morphological features can be effective for advance predictions, we measured gene-expression profiles of the same early undifferentiated cells. Both senescence-related genes (p16 and p21 and cytoskeleton-related genes (PTK2, CD146, and CD49 already correlated to the decrease of potentials at this stage. To objectively compare the performance of morphology and gene expression for such early prediction, we tested a range of models using various combinations of features. Such comparison of predictive performances revealed that morphological features performed better overall than gene-expression profiles, balancing the predictive accuracy with the effort required for model construction. This benchmark list of various prediction models not only identifies the best morphological feature

  18. Single cell transcriptome analysis using next generation sequencing.

    OpenAIRE

    Blattner, M.

    2010-01-01

    The heterogeneity of tissues, especially in cancer research, is a central issue in transcriptome analysis. In recent years, research has primarily focused on the development of methods for single cell analysis. Single cell analysis aims at gaining (novel) insights into biological processes of healthy and diseased cells. Some of the challenges in transcriptome analysis concern low abundance of sample starting material, necessary sample amplification steps and subsequent analysis. In this study...

  19. Generation of Breast Cancer Stem Cells by the EMT

    Science.gov (United States)

    2009-10-01

    non-CSCs. Strikingly, we found that salinomycin treatment reduced the representation of CSCs down to 0.2%, more than 300-fold decrease in the...relative representation of these cells in the cell population. In addition, we noted that salinomycin halted tumor growth in vivo and caused extensive...cells. In an initial proof-of-principle screen, we discovered two compounds – salinomycin and abamectin – that were characterized in detail. These

  20. Generations.

    Science.gov (United States)

    Chambers, David W

    2005-01-01

    Groups naturally promote their strengths and prefer values and rules that give them an identity and an advantage. This shows up as generational tensions across cohorts who share common experiences, including common elders. Dramatic cultural events in America since 1925 can help create an understanding of the differing value structures of the Silents, the Boomers, Gen Xers, and the Millennials. Differences in how these generations see motivation and values, fundamental reality, relations with others, and work are presented, as are some applications of these differences to the dental profession.

  1. Generation and Characterization of Patient-Specific Induced Pluripotent Stem Cell for Disease Modeling.

    Science.gov (United States)

    Sivapatham, Renuka; Zeng, Xianmin

    2016-01-01

    One major hurdle to the development of effective treatments to many diseases is the lack of suitable human model systems. The ability to reprogram human somatic cells to induced pluripotent stem cells (iPSC) offers an excellent opportunity to generate human disease models with primary cells. Currently, several methods to generate iPSC lines exist, and iPSC can be generated from various tissue sources including skin fibroblasts, blood, hair follicles, dental tissue, and urine. In this chapter we describe the generation and characterization of iPSC from blood or fibroblast on a routine base and focus on the integration-free methodologies.

  2. Generation of Spheres from Dental Epithelial Stem Cells

    Science.gov (United States)

    Natsiou, Despoina; Granchi, Zoraide; Mitsiadis, Thimios A.; Jimenez-Rojo, Lucia

    2017-01-01

    The in vitro three-dimensional sphere model has already been established as an important tool in fundamental sciences. This model facilitates the study of a variety of biological processes including stem cell/niche functions and tissue responses to injury and drugs. Here we describe the complete protocol for the in vitro formation of spheres originated from the epithelium of rodent incisors. In addition, we show that in these spheres cell proliferation is maintained, as well as the expression of several key molecules characterizing stem cells such as Sox2 and p63. These epithelial dentospheres could be used as an in vitro model system for stem cell research purposes. PMID:28154538

  3. A DNA vaccine encoding multiple HIV CD4 epitopes elicits vigorous polyfunctional, long-lived CD4+ and CD8+ T cell responses.

    Directory of Open Access Journals (Sweden)

    Daniela Santoro Rosa

    Full Text Available T-cell based vaccines against HIV have the goal of limiting both transmission and disease progression by inducing broad and functionally relevant T cell responses. Moreover, polyfunctional and long-lived specific memory T cells have been associated to vaccine-induced protection. CD4(+ T cells are important for the generation and maintenance of functional CD8(+ cytotoxic T cells. We have recently developed a DNA vaccine encoding 18 conserved multiple HLA-DR-binding HIV-1 CD4 epitopes (HIVBr18, capable of eliciting broad CD4(+ T cell responses in multiple HLA class II transgenic mice. Here, we evaluated the breadth and functional profile of HIVBr18-induced immune responses in BALB/c mice. Immunized mice displayed high-magnitude, broad CD4(+/CD8(+ T cell responses, and 8/18 vaccine-encoded peptides were recognized. In addition, HIVBr18 immunization was able to induce polyfunctional CD4(+ and CD8(+ T cells that proliferate and produce any two cytokines (IFNγ/TNFα, IFNγ/IL-2 or TNFα/IL-2 simultaneously in response to HIV-1 peptides. For CD4(+ T cells exclusively, we also detected cells that proliferate and produce all three tested cytokines simultaneously (IFNγ/TNFα/IL-2. The vaccine also generated long-lived central and effector memory CD4(+ T cells, a desirable feature for T-cell based vaccines. By virtue of inducing broad, polyfunctional and long-lived T cell responses against conserved CD4(+ T cell epitopes, combined administration of this vaccine concept may provide sustained help for CD8(+ T cells and antibody responses- elicited by other HIV immunogens.

  4. Effect of input multiplicity on the establishment of simian virus 40 persistent infections in rhesus monkey kidney cells.

    Science.gov (United States)

    Norkin, L C

    1977-12-01

    Monolayer cultures of LLC-MK2 rhesus monkey kidney cells become persistently infected with simian virus 40 after infection at input multiplicities of 100, 10, or 1 plaque-forming unit per cell. After 3 weeks, all cells of the cultures infected at a multiplicity of 1 plaque-forming unit per cell produced the simian virus 40 T antigen. In contrast, 8 to 11 weeks elapsed before all the cells in the cultures infected at a multiplicity of 100 plaque-forming units per cell produced T antigen. Defective interfering particles and interferon production were not evident during this time.

  5. Related B cell clones populate the meninges and parenchyma of patients with multiple sclerosis.

    Science.gov (United States)

    Lovato, Laura; Willis, Simon N; Rodig, Scott J; Caron, Tyler; Almendinger, Stefany E; Howell, Owain W; Reynolds, Richard; O'Connor, Kevin C; Hafler, David A

    2011-02-01

    In the central nervous system of patients with multiple sclerosis, B cell aggregates populate the meninges, raising the central question as to whether these structures relate to the B cell infiltrates found in parenchymal lesions or instead, represent a separate central nervous system immune compartment. We characterized the repertoires derived from meningeal B cell aggregates and the corresponding parenchymal infiltrates from brain tissue derived primarily from patients with progressive multiple sclerosis. The majority of expanded antigen-experienced B cell clones derived from meningeal aggregates were also present in the parenchyma. We extended this investigation to include 20 grey matter specimens containing meninges, 26 inflammatory plaques, 19 areas of normal appearing white matter and cerebral spinal fluid. Analysis of 1833 B cell receptor heavy chain variable region sequences demonstrated that antigen-experienced clones were consistently shared among these distinct compartments. This study establishes a relationship between extraparenchymal lymphoid tissue and parenchymal infiltrates and defines the arrangement of B cell clones that populate the central nervous system of patients with multiple sclerosis.

  6. Invited Article: Multiple-octave spanning high-energy mid-IR supercontinuum generation in bulk quadratic nonlinear crystals

    Science.gov (United States)

    Zhou, Binbin; Bache, Morten

    2016-08-01

    Bright and broadband coherent mid-IR radiation is important for exciting and probing molecular vibrations. Using cascaded nonlinearities in conventional quadratic nonlinear crystals like lithium niobate, self-defocusing near-IR solitons have been demonstrated that led to very broadband supercontinuum generation in the visible, near-IR, and short-wavelength mid-IR. Here we conduct an experiment where a mid-IR crystal is pumped in the mid-IR. The crystal is cut for noncritical interaction, so the three-wave mixing of a single mid-IR femtosecond pump source leads to highly phase-mismatched second-harmonic generation. This self-acting cascaded process leads to the formation of a self-defocusing soliton at the mid-IR pump wavelength and after the self-compression point multiple octave-spanning supercontinua are observed. The results were recorded in a commercially available crystal LiInS2 pumped in the 3-4 μm range with 85 fs 50 μJ pulse energy, with the broadest supercontinuum covering 1.6-7.0 μm. We measured up 30 μJ energy in the supercontinuum, and the energy promises to scale favorably with an increased pump energy. Other mid-IR crystals can readily be used as well to cover other pump wavelengths and target other supercontinuum wavelength ranges.

  7. Optimization of carrier multiplication for more effcient solar cells: the case of Sn quantum dots.

    Science.gov (United States)

    Allan, Guy; Delerue, Christophe

    2011-09-27

    We present calculations of impact ionization rates, carrier multiplication yields, and solar-power conversion efficiencies in solar cells based on quantum dots (QDs) of a semimetal, α-Sn. Using these results and previous ones on PbSe and PbS QDs, we discuss a strategy to select QDs with the highest carrier multiplication rate for more efficient solar cells. We suggest using QDs of materials with a close to zero band gap and a high multiplicity of the bands in order to favor the relaxation of photoexcited carriers by impact ionization. Even in that case, the improvement of the maximum solar-power conversion efficiency appears to be a challenging task.

  8. Human antigen-specific regulatory T cells generated by T cell receptor gene transfer.

    Directory of Open Access Journals (Sweden)

    Todd M Brusko

    Full Text Available BACKGROUND: Therapies directed at augmenting regulatory T cell (Treg activities in vivo as a systemic treatment for autoimmune disorders and transplantation may be associated with significant off-target effects, including a generalized immunosuppression that may compromise beneficial immune responses to infections and cancer cells. Adoptive cellular therapies using purified expanded Tregs represents an attractive alternative to systemic treatments, with results from animal studies noting increased therapeutic potency of antigen-specific Tregs over polyclonal populations. However, current methodologies are limited in terms of the capacity to isolate and expand a sufficient quantity of endogenous antigen-specific Tregs for therapeutic intervention. Moreover, FOXP3+ Tregs fall largely within the CD4+ T cell subset and are thus routinely MHC class II-specific, whereas class I-specific Tregs may function optimally in vivo by facilitating direct tissue recognition. METHODOLOGY/PRINCIPAL FINDINGS: To overcome these limitations, we have developed a novel means for generating large numbers of antigen-specific Tregs involving lentiviral T cell receptor (TCR gene transfer into in vitro expanded polyclonal natural Treg populations. Tregs redirected with a high-avidity class I-specific TCR were capable of recognizing the melanoma antigen tyrosinase in the context of HLA-A*0201 and could be further enriched during the expansion process by antigen-specific reactivation with peptide loaded artificial antigen presenting cells. These in vitro expanded Tregs continued to express FOXP3 and functional TCRs, and maintained the capacity to suppress conventional T cell responses directed against tyrosinase, as well as bystander T cell responses. Using this methodology in a model tumor system, murine Tregs designed to express the tyrosinase TCR effectively blocked antigen-specific effector T cell (Teff activity as determined by tumor cell growth and luciferase reporter

  9. A New Cell Block Method for Multiple Immunohistochemical Analysis of Circulating Tumor Cells in Patients with Liver Cancer

    Science.gov (United States)

    Nam, Soo Jeong; Yeo, Hyun Yang; Chang, Hee Jin; Kim, Bo Hyun; Hong, Eun Kyung; Park, Joong-Won

    2016-01-01

    Purpose We developed a new method of detecting circulating tumor cells (CTCs) in liver cancer patients by constructing cell blocks from peripheral blood cells, including CTCs, followed by multiple immunohistochemical analysis. Materials and Methods Cell blockswere constructed from the nucleated cell pellets of peripheral blood afterremoval of red blood cells. The blood cell blocks were obtained from 29 patients with liver cancer, and from healthy donor blood spikedwith seven cell lines. The cell blocks and corresponding tumor tissues were immunostained with antibodies to seven markers: cytokeratin (CK), epithelial cell adhesion molecule (EpCAM), epithelial membrane antigen (EMA), CK18, α-fetoprotein (AFP), Glypican 3, and HepPar1. Results The average recovery rate of spiked SW620 cells from blood cell blocks was 91%. CTCs were detected in 14 out of 29 patients (48.3%); 11/23 hepatocellular carcinomas (HCC), 1/2 cholangiocarcinomas (CC), 1/1 combined HCC-CC, and 1/3 metastatic cancers. CTCs from 14 patients were positive for EpCAM (57.1%), EMA (42.9%), AFP (21.4%), CK18 (14.3%), Gypican3 and CK (7.1%, each), and HepPar1 (0%). Patients with HCC expressed EpCAM, EMA, CK18, and AFP in tissue and/or CTCs, whereas CK, HepPar1, and Glypican3 were expressed only in tissue. Only EMA was significantly associated with the expressions in CTC and tissue. CTC detection was associated with higher T stage and portal vein invasion in HCC patients. Conclusion This cell block method allows cytologic detection and multiple immunohistochemical analysis of CTCs. Our results show that tissue biomarkers of HCC may not be useful for the detection of CTC. EpCAM could be a candidate marker for CTCs in patients with HCC. PMID:27034142

  10. B cells populating the multiple sclerosis brain mature in the draining cervical lymph nodes

    NARCIS (Netherlands)

    J.N.H. Stern (Joel N. H.); G. Yaari (Gur); J. Vander Heiden (Jason); G.M. Church (George); W.F. Donahue (William F.); R.Q. Hintzen (Rogier); A.J. Huttner (Anita J.); J.D. Laman (Jon); R.M. Nagra (Rashed M.); A. Nylander (Alyssa); D. Pitt (David); S. Ramanan (Sriram); B.A. Siddiqui (Bilal A.); F. Vigneault (Francois); S.H. Kleinstein (Steven H.); D.A. Hafler (David); K. O'Connor (Kevin)

    2014-01-01

    textabstractMultiple sclerosis (MS) is an inflammatory disease of the central nervous system (CNS) characterized by autoimmunemediated demyelination and neurodegeneration. The CNS of patients withMSharbors expanded clones of antigen-experienced B cells that reside in distinct compartments including

  11. Multiparametric flow cytometry profiling of neoplastic plasma cells in multiple myeloma

    DEFF Research Database (Denmark)

    Johnsen, Hans E; Bøgsted, Martin; Klausen, Tobias W;

    2010-01-01

    The clinical impact of multiparametric flow cytometry (MFC) in multiple myeloma (MM) is still unclear and under evaluation. Further progress relies on multiparametric profiling of the neoplastic plasma cell (PC) compartment to provide an accurate image of the stage of differentiation. The primary...

  12. Optimal Assignment of Cells in C-RAN Deployments with Multiple BBU Pools

    DEFF Research Database (Denmark)

    Holm, Henrik; Checko, Aleksandra; Al-obaidi, Rami;

    2015-01-01

    recommend to divide the area into multiple BBU Pools. In this paper we show how to optimally assign cells to different BBU Pools in such a scenario. By using Integer Linear Programming (ILP) method we derive engineering guidelines for minimizing the CAPital EXpenditure (CAPEX) of C-RAN deployment....

  13. Generation of induced pluripotent stem cells from the pig

    Science.gov (United States)

    The value of stem cells has become increasingly evident in recent years with the advent of genetic engineering tools that allow site-specific modifications to the genome. The use of stem cells to induce modifications has several potential benefits for the livestock industry including improving anim...

  14. Systematic identification of yeast cell cycle transcription factors using multiple data sources

    Directory of Open Access Journals (Sweden)

    Li Wen-Hsiung

    2008-12-01

    Full Text Available Abstract Background Eukaryotic cell cycle is a complex process and is precisely regulated at many levels. Many genes specific to the cell cycle are regulated transcriptionally and are expressed just before they are needed. To understand the cell cycle process, it is important to identify the cell cycle transcription factors (TFs that regulate the expression of cell cycle-regulated genes. Results We developed a method to identify cell cycle TFs in yeast by integrating current ChIP-chip, mutant, transcription factor binding site (TFBS, and cell cycle gene expression data. We identified 17 cell cycle TFs, 12 of which are known cell cycle TFs, while the remaining five (Ash1, Rlm1, Ste12, Stp1, Tec1 are putative novel cell cycle TFs. For each cell cycle TF, we assigned specific cell cycle phases in which the TF functions and identified the time lag for the TF to exert regulatory effects on its target genes. We also identified 178 novel cell cycle-regulated genes, among which 59 have unknown functions, but they may now be annotated as cell cycle-regulated genes. Most of our predictions are supported by previous experimental or computational studies. Furthermore, a high confidence TF-gene regulatory matrix is derived as a byproduct of our method. Each TF-gene regulatory relationship in this matrix is supported by at least three data sources: gene expression, TFBS, and ChIP-chip or/and mutant data. We show that our method performs better than four existing methods for identifying yeast cell cycle TFs. Finally, an application of our method to different cell cycle gene expression datasets suggests that our method is robust. Conclusion Our method is effective for identifying yeast cell cycle TFs and cell cycle-regulated genes. Many of our predictions are validated by the literature. Our study shows that integrating multiple data sources is a powerful approach to studying complex biological systems.

  15. Generation and application of human iPS cells

    Institute of Scientific and Technical Information of China (English)

    CUI Ghun; RAO LingJun; CHENG LinZhao; XIAO Lei

    2009-01-01

    Human embryonic stem (ES) cells are capable of unlimited proliferation and maintenance of pluripo-tency in vitro; these properties may lead to potential applications in regenerative medicine.However,immune rejection hampers the allogenic application of human ES cells.Over-expression of several specific transcription factors has been used to reprogram human adult cells into induced pluripotent stem (iPS) cells,which are similar to hESCs in many aspects.The iPS technique makes it possible to produce patient-specific pluripotent stem cells for transplantation therapy without immune rejection.However,some challenges remain,including viral vector integration into the genome,the existence of exogenous oncogenic factors,and low induction efficiency.Here,we review recent advances in human iPS methodology,as well as remaining challenges and its potential applications.

  16. Monolithic fuel cell based power source for burst power generation

    Science.gov (United States)

    Fee, D. C.; Blackburn, P. E.; Busch, D. E.; Dees, D. W.; Dusek, J.; Easler, T. E.; Ellingson, W. A.; Flandermeyer, B. K.; Fousek, R. J.; Heiberger, J. J.

    A unique fuel cell coupled with a low power nuclear reactor presents an attractive approach for SDI burst power requirements. The monolithic fuel cell looks attractive for space applications and represents a quantum jump in fuel cell technology. Such a breakthrough in design is the enabling technology for lightweight, low volume power sources for space based pulse power systems. The monolith is unique among fuel cells in being an all solid state device. The capability for miniaturization, inherent in solid state devices, gives the low volume required for space missions. In addition, the solid oxide fuel cell technology employed in the monolith has high temperature reject heat and can be operated in either closed or open cycles. Both these features are attractive for integration into a burst power system.

  17. Generation and Regulation of CD8+ Regulatory T Cells

    Institute of Scientific and Technical Information of China (English)

    Linrong Lu; Harvey Cantor

    2008-01-01

    Research into the suppressive activity of CD4+FoxP3+ T regulatory cells (Treg) has defined a sublineage of CD4+ cells that contribute to self-tolerance and resistance to autoimmune disease. Much less attention has been given to the potential contribution of regulatory sublineages of CD8+ cells. Analysis of a small fraction of CD8+ cells that target autoreactive CD4+ cells through recognition of the MHC class Ib molecule Qa-1 in mouse and HLA-E in human has revitalized interest in CD8+ Treg. Here we summarize recent progress and future directions of research into the role of this CD8+ sublineage in resistance to autoimmune disease. Cellular & Molecular Immunology. 2008;5(6):401-406.

  18. A Case of Mature Natural Killer-Cell Neoplasm Manifesting Multiple Choroidal Lesions: Primary Intraocular Natural Killer-Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Yoshiaki Tagawa

    2015-11-01

    Full Text Available Purpose: Natural killer (NK cell neoplasm is a rare disease that follows an acute course and has a poor prognosis. It usually emerges from the nose and appears in the ocular tissue as a metastasis. Herein, we describe a case of NK-cell neoplasm in which the eye was considered to be the primary organ. Case: A 50-year-old female displayed bilateral anterior chamber cells, vitreous opacity, bullous retinal detachment, and multiple white choroidal mass lesions. Although malignant lymphoma or metastatic tumor was suspected, various systemic examinations failed to detect any positive results. A vitrectomy was performed OS; however, histocytological analyses from the vitreous sample showed no definite evidence of malignancy, and IL-10 concentration was low. Enlarged choroidal masses were fused together. Three weeks after the first visit, the patient suddenly developed an attack of fever, night sweat, and hepatic dysfunction, and 5 days later, she passed away due to multiple organ failure. Immunohistochemisty and in situ hybridization revealed the presence of atypical cells positive for CD3, CD56, and Epstein-Barr virus-encoded RNAs, resulting in the diagnosis of NK-cell neoplasm. With the characteristic clinical course, we concluded that this neoplasm was a primary intraocular NK-cell lymphoma. Conclusions: This is the first report to describe primary intraocular NK-cell neoplasm. When we encounter atypical choroidal lesions, we should consider the possibility of NK-cell lymphoma, even though it is a rare disease.

  19. A Case of Mature Natural Killer-Cell Neoplasm Manifesting Multiple Choroidal Lesions: Primary Intraocular Natural Killer-Cell Lymphoma

    Science.gov (United States)

    Tagawa, Yoshiaki; Namba, Kenichi; Ogasawara, Reiki; Kanno, Hiromi; Ishida, Susumu

    2015-01-01

    Purpose Natural killer (NK) cell neoplasm is a rare disease that follows an acute course and has a poor prognosis. It usually emerges from the nose and appears in the ocular tissue as a metastasis. Herein, we describe a case of NK-cell neoplasm in which the eye was considered to be the primary organ. Case A 50-year-old female displayed bilateral anterior chamber cells, vitreous opacity, bullous retinal detachment, and multiple white choroidal mass lesions. Although malignant lymphoma or metastatic tumor was suspected, various systemic examinations failed to detect any positive results. A vitrectomy was performed OS; however, histocytological analyses from the vitreous sample showed no definite evidence of malignancy, and IL-10 concentration was low. Enlarged choroidal masses were fused together. Three weeks after the first visit, the patient suddenly developed an attack of fever, night sweat, and hepatic dysfunction, and 5 days later, she passed away due to multiple organ failure. Immunohistochemisty and in situ hybridization revealed the presence of atypical cells positive for CD3, CD56, and Epstein-Barr virus-encoded RNAs, resulting in the diagnosis of NK-cell neoplasm. With the characteristic clinical course, we concluded that this neoplasm was a primary intraocular NK-cell lymphoma. Conclusions This is the first report to describe primary intraocular NK-cell neoplasm. When we encounter atypical choroidal lesions, we should consider the possibility of NK-cell lymphoma, even though it is a rare disease. PMID:26668579

  20. Effects of arsenic trioxide on voltage-dependent potassium channels and on cell proliferation of human multiple myeloma cells

    Institute of Scientific and Technical Information of China (English)

    ZHOU Jin; WANG Wei; WEI Qing-fang; FENG Tie-ming; TAN Li-jun; YANG Bao-feng

    2007-01-01

    @@ Arsenic trioxide (ATO) can induce cellular apoptosis and inhibit the activities of multiple myeloma (MM)cells in vitro,1 but how it works is not very clear. Recent studies showed that ATO worked on the voltagedependent potassium channel and L-type calcium channel in myocardial cells,2-5 but the effect of ATO on ion channels of tumor cells was rarely reported. As the potassium channel plays an important role in controlling cell proliferation,6 we studied the effects of ATO on the voltage-dependent potassium current (Ikv) of the voltage-dependent potassium channel in an MM cell line,and probed into the relationship between changes of the Ikv caused by ATO and cell proliferation.

  1. Effects of Voltage-Gated K+ Channel on Cell Proliferation in Multiple Myeloma

    Directory of Open Access Journals (Sweden)

    Wei Wang

    2014-01-01

    Full Text Available Objective. To study the effects and underlying mechanisms of voltage-gated K+ channels on the proliferation of multiple myeloma cells. Methods. RPMI-8226 MM cell line was used for the experiments. Voltage-gated K+ currents and the resting potential were recorded by whole-cell patch-clamp technique. RT-PCR detected Kv channel mRNA expression. Cell viability was analyzed with MTT assay. Cell counting system was employed to monitor cell proliferation. DNA contents and cell volume were analyzed by flow cytometry. Results. Currents recorded in RPMI-8226 cells were confirmed to be voltage-gated K+ channels. A high level of Kv1.3 mRNA was detected but no Kv3.1 mRNA was detected in RPMI-8226 cells. Voltage-gated K+ channel blocker 4-aminopyridine (4-AP (2 mM depolarized the resting potential from −42 ± 1.7 mV to −31.8 ± 2.8 mV (P0.05. Conclusions. In RPMI-8226, voltage-gated K+ channels are involved in proliferation and cell cycle progression its influence on the resting potential and cell volume may be responsible for this process; the inhibitory effect of the voltage-gated K+ channel blocker on RPMI-8226 cell proliferation is a phase-specific event.

  2. Generation of Patient-Specific induced Pluripotent Stem Cell from Peripheral Blood Mononuclear Cells by Sendai Reprogramming Vectors.

    Science.gov (United States)

    Quintana-Bustamante, Oscar; Segovia, Jose C

    2016-01-01

    Induced pluripotent stem cells (iPSC) technology has changed preclinical research since their generation was described by Shinya Yamanaka in 2006. iPSCs are derived from somatic cells after being reprogrammed back to an embryonic state by specific combination of reprogramming factors. These reprogrammed cells resemble all the characteristic of embryonic stem cells (ESC). The reprogramming technology is even more valuable to research diseases biology and treatment by opening gene and cell therapies in own patient's iPSC. Patient-specific iPSC can be generated from a large variety of patient cells by any of the myriad of reprogramming platforms described. Here, we describe the generation of patient-specific iPSC from patient peripheral blood mononuclear cells by Sendai Reprogramming vectors.

  3. A Mathematical Model of Baculovirus Infection on Insect Cells at Low Multiplicity of Infection

    Institute of Scientific and Technical Information of China (English)

    You-Hong ZHANG; Josée C. MERCHUK

    2004-01-01

    The expression efficiency of the insect cells-baculovirus system used for insecticidal virus production and the expression of medically useful foreign genes is closely related with the dynamics of infection. The present studies develop a model of the dynamic process of insect cell infection with baculovirus at low multiplicity of infection (MOI), which is based on the multi-infection cycles of insect cell infection at low MOI. A mathematical model for the amount of viruses released from primary infected cells and the amount of free viruses before secondary infected cells release viruses has been developed. Comparison of the simulation results with the experimental data confirms qualitatively that this model is highly reasonable before secondary infected cells release viruses. This model is considered as a base for further modeling the entire complicated infection process.

  4. In Vivo Monitoring of Multiple Circulating Cell Populations Using Two-photon Flow Cytometry.

    Science.gov (United States)

    Tkaczyk, Eric R; Zhong, Cheng Frank; Ye, Jing Yong; Myc, Andrzej; Thomas, Thommey; Cao, Zhengyi; Duran-Struuck, Raimon; Luker, Kathryn E; Luker, Gary D; Norris, Theodore B; Baker, James R

    2008-02-15

    To detect and quantify multiple distinct populations of cells circulating simultaneously in the blood of living animals, we developed a novel optical system for two-channel, two-photon flow cytometry in vivo. We used this system to investigate the circulation dynamics in live animals of breast cancer cells with low (MCF-7) and high (MDA-MB-435) metastatic potential, showing for the first time that two different populations of circulating cells can be quantified simultaneously in the vasculature of a single live mouse. We also non-invasively monitored a population of labeled, circulating red blood cells for more than two weeks, demonstrating that this technique can also quantify the dynamics of abundant cells in the vascular system for prolonged periods of time. These data are the first in vivo application of multichannel flow cytometry utilizing two-photon excitation, which will greatly enhance our capability to study circulating cells in cancer and other disease processes.

  5. CRISPR/Cas9-Mediated Rapid Generation of Multiple Mouse Lines Identified Ccdc63 as Essential for Spermiogenesis

    Directory of Open Access Journals (Sweden)

    Samantha A. M. Young

    2015-10-01

    Full Text Available Spermatozoa are flagellated cells whose role in fertilization is dependent on their ability to move towards an oocyte. The structure of the sperm flagella is highly conserved across species, and much of what is known about this structure is derived from studies utilizing animal models. One group of proteins essential for the movement of the flagella are the dyneins. Using the advanced technology of CRISPR/Cas9 we have targeted three dynein group members; Dnaic1, Wdr63 and Ccdc63 in mice. All three of these genes are expressed strongly in the testis. We generated mice with amino acid substitutions in Dnaic1 to analyze two specific phosphorylation events at S124 and S127, and generated simple knockouts of Wdr63 and Ccdc63. We found that the targeted phosphorylation sites in Dnaic1 were not essential for male fertility. Similarly, Wdr63 was not essential for male fertility; however, Ccdc63 removal resulted in sterile male mice due to shortened flagella. This study demonstrates the versatility of the CRISPR/Cas9 system to generate animal models of a highly complex system by introducing point mutations and simple knockouts in a fast and efficient manner.

  6. Current protocols in the generation of pluripotent stem cells: theoretical, methodological and clinical considerations

    Directory of Open Access Journals (Sweden)

    Brad B Swelstad

    2009-12-01

    Full Text Available Brad B Swelstad, Candace L KerrInstitute for Cell Engineering, Department of Obstetrics and Gynecology, Johns Hopkins University, Baltimore, MA, USAAbstract: Pluripotent stem cells have been derived from various embryonic, fetal and adult sources. Embryonic stem cells (ESCs and parthenogenic ESCs (pESCs are derived from the embryo proper while embryonic germ cells (EGCs, embryonal carcinoma cells (ECCs, and germ-line stem cells (GSC are produced from germ cells. ECCs were the first pluripotent stem cell lines established from adult testicular tumors while EGCs are generated in vitro from primordial germ cells (PGCs isolated in late embryonic development. More recently, studies have also demonstrated the ability to produce GSCs from adult germ cells, known as spermatogonial stem cells. Unlike ECCs, the source of GSCs are normal, non-cancerous adult tissue. The study of these unique cell lines has provided information that has led to the ability to reprogram somatic cells into an ESC-like state. These cells, called induced pluripotent stem cells (iPSCs, have been derived from a number of human fetal and adult origins. With the promises pluripotent stem cells bring to cell-based therapies there remain several considerations that need to be carefully studied prior to their clinical use. Many of these issues involve understanding key factors regulating their generation, including those which define pluripotency. In this regard, the following article discusses critical aspects of pluripotent stem cell derivation and current issues about their therapeutic potential.Keywords: pluripotency, stem cells, derivation, human

  7. Generation of Recombinant Monoclonal Antibodies from Immunised Mice and Rabbits via Flow Cytometry and Sorting of Antigen-Specific IgG+ Memory B Cells.

    Directory of Open Access Journals (Sweden)

    Dale O Starkie

    Full Text Available Single B cell screening strategies, which avoid both hybridoma fusion and combinatorial display, have emerged as important technologies for efficiently sampling the natural antibody repertoire of immunized animals and humans. Having access to a range of methods to interrogate different B cell subsets provides an attractive option to ensure large and diverse panels of high quality antibody are produced. The generation of multiple antibodies and having the ability to find rare B cell clones producing IgG with unique and desirable characteristics facilitates the identification of fit-for-purpose molecules that can be developed into therapeutic agents or research reagents. Here, we describe a multi-parameter flow cytometry single-cell sorting technique for the generation of antigen-specific recombinant monoclonal antibodies from single IgG+ memory B cells. Both mouse splenocytes and rabbit PBMC from immunised animals were used as a source of B cells. Reagents staining both B cells and other unwanted cell types enabled efficient identification of class-switched IgG+ memory B cells. Concurrent staining with antigen labelled separately with two spectrally-distinct fluorophores enabled antigen-specific B cells to be identified, i.e. those which bind to both antigen conjugates (double-positive. These cells were then typically sorted at one cell per well using FACS directly into a 96-well plate containing reverse transcriptase reaction mix. Following production of cDNA, PCR was performed to amplify cognate heavy and light chain variable region genes and generate transcriptionally-active PCR (TAP fragments. These linear expression cassettes were then used directly in a mammalian cell transfection to generate recombinant antibody for further testing. We were able to successfully generate antigen-specific recombinant antibodies from both the rabbit and mouse IgG+ memory B cell subset within one week. This included the generation of an anti-TNFR2 blocking

  8. Generation and characterization of induced pluripotent stem cells from Aid-deficient mice.

    Directory of Open Access Journals (Sweden)

    Ren Shimamoto

    Full Text Available It has been shown that DNA demethylation plays a pivotal role in the generation of induced pluripotent stem (iPS cells. However, the underlying mechanism of this action is still unclear. Previous reports indicated that activation-induced cytidine deaminase (Aid, also known as Aicda is involved in DNA demethylation in several developmental processes, as well as cell fusion-mediated reprogramming. Based on these reports, we hypothesized that Aid may be involved in the DNA demethylation that occurs during the generation of iPS cells. In this study, we examined the function of Aid in iPS cell generation using Aid knockout (Aid⁻/⁻ mice expressing a GFP reporter under the control of a pluripotent stem cell marker, Nanog. By introducing Oct3/4, Sox2, Klf4 and c-Myc, Nanog-GFP-positive iPS cells could be generated from the fibroblasts and primary B cells of Aid⁻/⁻ mice. Their induction efficiency was similar to that of wild-type (Aid⁺/⁺ iPS cells. The Aid⁻/⁻ iPS cells showed normal proliferation and gave rise to chimeras, indicating their capacity for self-renewal and pluripotency. A comprehensive DNA methylation analysis showed only a few differences between Aid⁺/⁺ and Aid⁻/⁻ iPS cells. These data suggest that Aid does not have crucial functions in DNA demethylation during iPS cell generation.

  9. Epigenetic reprogramming of human embryonic stem cells into skeletal muscle cells and generation of contractile myospheres.

    Science.gov (United States)

    Albini, Sonia; Coutinho, Paula; Malecova, Barbora; Giordani, Lorenzo; Savchenko, Alex; Forcales, Sonia Vanina; Puri, Pier Lorenzo

    2013-03-28

    Direct generation of a homogeneous population of skeletal myoblasts from human embryonic stem cells (hESCs) and formation of three-dimensional contractile structures for disease modeling in vitro are current challenges in regenerative medicine. Previous studies reported on the generation of myoblasts from ESC-derived embryoid bodies (EB), but not from undifferentiated ESCs, indicating the requirement for mesodermal transition to promote skeletal myogenesis. Here, we show that selective absence of the SWI/SNF component BAF60C (encoded by SMARCD3) confers on hESCs resistance to MyoD-mediated activation of skeletal myogenesis. Forced expression of BAF60C enables MyoD to directly activate skeletal myogenesis in hESCs by instructing MyoD positioning and allowing chromatin remodeling at target genes. BAF60C/MyoD-expressing hESCs are epigenetically committed myogenic progenitors, which bypass the mesodermal requirement and, when cultured as floating clusters, give rise to contractile three-dimensional myospheres composed of skeletal myotubes. These results identify BAF60C as a key epigenetic determinant of hESC commitment to the myogenic lineage and establish the molecular basis for the generation of hESC-derived myospheres exploitable for "disease in a dish" models of muscular physiology and dysfunction.

  10. Epigenetic Reprogramming of Human Embryonic Stem Cells into Skeletal Muscle Cells and Generation of Contractile Myospheres

    Directory of Open Access Journals (Sweden)

    Sonia Albini

    2013-03-01

    Full Text Available Direct generation of a homogeneous population of skeletal myoblasts from human embryonic stem cells (hESCs and formation of three-dimensional contractile structures for disease modeling in vitro are current challenges in regenerative medicine. Previous studies reported on the generation of myoblasts from ESC-derived embryoid bodies (EB, but not from undifferentiated ESCs, indicating the requirement for mesodermal transition to promote skeletal myogenesis. Here, we show that selective absence of the SWI/SNF component BAF60C (encoded by SMARCD3 confers on hESCs resistance to MyoD-mediated activation of skeletal myogenesis. Forced expression of BAF60C enables MyoD to directly activate skeletal myogenesis in hESCs by instructing MyoD positioning and allowing chromatin remodeling at target genes. BAF60C/MyoD-expressing hESCs are epigenetically committed myogenic progenitors, which bypass the mesodermal requirement and, when cultured as floating clusters, give rise to contractile three-dimensional myospheres composed of skeletal myotubes. These results identify BAF60C as a key epigenetic determinant of hESC commitment to the myogenic lineage and establish the molecular basis for the generation of hESC-derived myospheres exploitable for “disease in a dish” models of muscular physiology and dysfunction.

  11. Utility of Lymphoblastoid Cell Lines for Induced Pluripotent Stem Cell Generation

    Directory of Open Access Journals (Sweden)

    Satish Kumar

    2016-01-01

    Full Text Available A large number of EBV immortalized LCLs have been generated and maintained in genetic/epidemiological studies as a perpetual source of DNA and as a surrogate in vitro cell model. Recent successes in reprograming LCLs into iPSCs have paved the way for generating more relevant in vitro disease models using this existing bioresource. However, the overall reprogramming efficiency and success rate remain poor and very little is known about the mechanistic changes that take place at the transcriptome and cellular functional level during LCL-to-iPSC reprogramming. Here, we report a new optimized LCL-to-iPSC reprogramming protocol using episomal plasmids encoding pluripotency transcription factors and mouse p53DD (p53 carboxy-terminal dominant-negative fragment and commercially available reprogramming media. We achieved a consistently high reprogramming efficiency and 100% success rate using this optimized protocol. Further, we investigated the transcriptional changes in mRNA and miRNA levels, using FC-abs ≥ 2.0 and FDR ≤ 0.05 cutoffs; 5,228 mRNAs and 77 miRNAs were differentially expressed during LCL-to-iPSC reprogramming. The functional enrichment analysis of the upregulated genes and activation of human pluripotency pathways in the reprogrammed iPSCs showed that the generated iPSCs possess transcriptional and functional profiles very similar to those of human ESCs.

  12. Bio-electrochemical treatment of distillery wastewater in microbial fuel cell facilitating decolorization and desalination along with power generation.

    Science.gov (United States)

    Mohanakrishna, G; Venkata Mohan, S; Sarma, P N

    2010-05-15

    Microbial fuel cell (MFC; open-air cathode) was evaluated as bio-electrochemical treatment system for distillery wastewater during bioelectricity generation. MFC was operated at three substrate loading conditions in fed-batch mode under acidophilic (pH 6) condition using anaerobic consortia as anodic-biocatalyst. Current visualized marked improvement with increase in substrate load without any process inhibition (2.12-2.48mA). Apart from electricity generation, MFC documented efficient treatment of distillery wastewater and illustrated its function as an integrated wastewater treatment system by simultaneously removing multiple pollutants. Fuel cell operation yielded enhanced substrate degradation (COD, 72.84%) compared to the fermentation process ( approximately 29.5% improvement). Interestingly due to treatment in MFC, considerable reduction in color (31.67%) of distillery wastewater was also observed as against color intensification normally observed due to re-polymerization in corresponding anaerobic process. Good reduction in total dissolved solids (TDS, 23.96%) was also noticed due to fuel cell operation, which is generally not amenable in biological treatment. The simultaneous removal of multiple pollutants observed in distillery wastewater might be attributed to the biologically catalyzed electrochemical reactions occurring in the anodic chamber of MFC mediated by anaerobic substrate metabolism.

  13. Chemokine receptor expression on B cells and effect of interferon-beta in multiple sclerosis

    DEFF Research Database (Denmark)

    Sørensen, Torben Lykke; Roed, Hanne; Sellebjerg, Finn

    2002-01-01

    We investigated the B-cell expression of chemokine receptors CXCR3, CXCR5 and CCR5 in the blood and cerebrospinal fluid (CSF) from patients in relapse of multiple sclerosis (MS) and in neurological controls. Chemokine receptor expression was also studied in interferon-beta-treated patients...... with relapsing-remitting or secondary progressive MS. We observed significantly higher expression of CXCR3 on B cells in the CSF in active MS than in controls. Patients with active MS also had higher B-cell expression of CCR5 in blood. No major differences between RRMS and SPMS patients were detected...

  14. Multi-peak Phenomenon of Insect Cell Infection with Baculovirus at Low Multiplicity of Infection

    Institute of Scientific and Technical Information of China (English)

    You-Hong ZHANG

    2005-01-01

    In this communication we report the infection of armyworm Spodoptera frugiperda IPLB-Sf21 cells with Anticarsia gemmatalis multicapsid nucleopolyhedrovirus at low multiplicity of infection (MOI).The temporal variation of the extra-cellular virus and of the unstained cell was followed. The series of peaks in the virus concentration and the unstained cells count were used in order to infer the dynamic mechanism of the infection at low MOI. This mechanism can be used as the basis for the future formulation of a mathematical model of the process.

  15. Realizing the next generation of CPV cells using transfer printing

    Science.gov (United States)

    Lumb, Matthew P.; Schmieder, Kenneth J.; González, María; Mack, Shawn; Yakes, Michael K.; Meitl, Matthew; Burroughs, Scott; Ebert, Chris; Bennett, Mitchell F.; Forbes, David V.; Sheng, Xing; Rogers, John A.; Walters, Robert J.

    2015-09-01

    Transfer-printing is an important, commercial technology for manufacturing state of the art CPV modules, and has emerged recently as a key enabling technology for the realization of ultra-high-efficiency, mechanically stacked III-V solar cells with low cost. This paper presents the latest results for microscale CPV cells grown on GaAs, InP and GaSb substrates for ultra-high-efficiency, four-terminal, mechanically stacked architectures. The latest findings from a combination of modeling, growth, processing and characterization of single and multijunction solar cells are described, and the roadmap to the long-term goal of using transfer-printing to produce the first solar cell with 50% conversion efficiency is outlined.

  16. Apoptotic effects of non-edible parts of Punica granatum on human multiple myeloma cells.

    Science.gov (United States)

    Kiraz, Yağmur; Neergheen-Bhujun, Vidushi S; Rummun, Nawraj; Baran, Yusuf

    2016-02-01

    Multiple myeloma is of great concern since existing therapies are unable to cure this clinical condition. Alternative therapeutic approaches are mandatory, and the use of plant extracts is considered interesting. Punica granatum and its derived products were suggested as potential anticancer agents due to the presence of bioactive compounds. Thus, polypenolic-rich extracts of the non-edible parts of P. granatum were investigated for their antiproliferative and apoptotic effects on U266 multiple myeloma cells. We demonstrated that there were dose-dependent decreases in the proliferation of U266 cells in response to P. granatum extracts. Also, exposure to the extracts triggered apoptosis with significant increases in loss of mitochondrial membrane potential in U266 cells exposed to the leaves and stem extracts, while the flower extract resulted in slight increases in loss of MMP. These results were confirmed by Annexin-V analysis. These results documented the cytotoxic and apoptotic effects of P. granatum extracts on human U266 multiple myeloma cells via disruption of mitochondrial membrane potential and increasing cell cycle arrest. The data suggest that the extracts can be envisaged in cancer chemoprevention and call for further exploration into the potential application of these plant parts.