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Sample records for prelabeled ma104 cells

  1. Isolation and propagation of the animal rotaviruses in MA-104 cells--30 years of practical experience.

    Science.gov (United States)

    Otto, Peter H; Reetz, Jochen; Eichhorn, Werner; Herbst, Werner; Elschner, Mandy C

    2015-10-01

    A total of 136 rotavirus positive samples from diarrhoeic animals of different species were submitted for isolation and cultural propagation of rotavirus on MA-104 cells. The samples were collected from animals with diarrhoea, between 1980 and 2010, originating from herds or farms located in several parts of Germany. Rotaviruses of species A were isolated from 102 faecal samples in cultures of MA-104 cells under the following conditions: pre-treatment of virus with trypsin, incorporation of trypsin into culture medium, use of roller cultures, and centrifugation of the samples on the cells. The cell culture adapted viruses produced a cytopathic effect, accompanied by the release of cells from the glass surface of the cultivation vessels. After 10 passages the virus isolates yielded titres between 10(5.5) and 10(7.5)ml(-1) TCID50. Isolation and serial propagation of the virus in MA-104 cells was confirmed by immunofluorescence assay, transmission electron microscopy, and polyacrylamide-gel electrophoresis of viral dsRNA. Eight (5.9%) of the electrophoretic profiles were characteristic of species B or D rotaviruses, which were not replicated in MA-104 cells.

  2. The shift from low to high non-structural protein 1 expression in rotavirus-infected MA-104 cells

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    Laura Martinez-Alvarez

    2013-06-01

    Full Text Available A hallmark of group/species A rotavirus (RVA replication in MA-104 cells is the logarithmic increase in viral mRNAs that occurs four-12 h post-infection. Viral protein synthesis typically lags closely behind mRNA synthesis but continues after mRNA levels plateau. However, RVA non-structural protein 1 (NSP1 is present at very low levels throughout viral replication despite showing robust protein synthesis. NSP1 has the contrasting properties of being susceptible to proteasomal degradation, but being stabilised against proteasomal degradation by viral proteins and/or viral mRNAs. We aimed to determine the kinetics of the accumulation and intracellular distribution of NSP1 in MA-104 cells infected with rhesus rotavirus (RRV. NSP1 preferentially localises to the perinuclear region of the cytoplasm of infected cells, forming abundant granules that are heterogeneous in size. Late in infection, large NSP1 granules predominate, coincident with a shift from low to high NSP1 expression levels. Our results indicate that rotavirus NSP1 is a late viral protein in MA-104 cells infected with RRV, presumably as a result of altered protein turnover.

  3. The tight junction protein JAM-A functions as coreceptor for rotavirus entry into MA104 cells.

    Science.gov (United States)

    Torres-Flores, Jesús M; Silva-Ayala, Daniela; Espinoza, Marco A; López, Susana; Arias, Carlos F

    2015-01-15

    Several molecules have been identified as receptors or coreceptors for rotavirus infection, including glycans, integrins, and hsc70. In this work we report that the tight junction proteins JAM-A, occludin, and ZO-1 play an important role during rotavirus entry into MA104 cells. JAM-A was found to function as coreceptor for rotavirus strains RRV, Wa, and UK, but not for rotavirus YM. Reassortant viruses derived from rotaviruses RRV and YM showed that the virus spike protein VP4 determines the use of JAM-A as coreceptor.

  4. 犬瘟热病毒在MA-104、Marc-145、Vero3种细胞内增殖效果的比较%Comparison on Multiplication Effect of Canine Distemper Virus in MA-104, Marc-145, and Vero Cells

    Institute of Scientific and Technical Information of China (English)

    王朝蕾; 崔卓宇; 吕永钢; 胡江锋; 焦铁军; 樊军喜; 王根红; 崔瑞宁

    2012-01-01

    试验比较了MA-104、Marc-145、Vero3种猴肾细胞增殖犬瘟热病毒的敏感性,按常规方法将犬瘟热病毒(CDV—XN112株)分别接种于MA-104、Marc-145、Vero3种细胞,通过观察细胞病变,确定收毒时间,比较病毒滴度。结果表明,犬瘟热病毒可在MA-104、Marc-145、Vero3种细胞内增殖,并出现典型细胞病变,效价均达到10^4.5TCID50/0.1mL以上.而Vero细胞增殖犬瘟热病毒更为经济高效,是增殖该病毒的理想细胞。%After canine distemper virus (CDV-XN 112 strain) was inoculated into MA- 104, Marc- 145 and Vero cells, the sensitivity of three types of monkey kidney to CDV was compared by observing cell pathological effect, determining the time for harvesting virus and comparing virus titers. The results showed that three cells were suitable for CDV, with typical cell pathological effect, and the titers of virus harvest fluids were more than 104.5 TCID50/0. lmL, among them Vero cell was more cost-effective and ideal for proliferation CDV.

  5. ACUMULACIÓN DE LA PROTEÍNA DE CHOQUE TÉRMICO, HSC70, EN CÉLULAS MA104 DESPUÉS DE LA INFECCIÓN CON ROTAVIRUS Increase of heat shock cognate protein, HSC70, in MA104 cells following rotavirus infection

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    Diana Rocio Pulido Morera

    2007-12-01

    rotavirus particles during the infection of MA104 cells, but changes in the accumulation levels of this protein through the rotavirus infection cycle are unknown. Objetive. To determine if the accumulation levels of HSC70 in MA104 cells change during the infection by rotavirus. Materials and methods. Immunofluorescene microscopy, Western blotting an ELISA were used in order to determine HSC70 accumulation levels in MA104 cells after infection (0 up to 16 h p.i. by rotavirus strains Wa (human, Rf (bovine and RRV (simian. Additionally, a rabbit polyclonal serum against purified rotavirus particles was used for detecting rotavirus antigen in an immunoperoxidase assay. Results. The immunofluorescence staining of cells infected with each of three rotavirus strains showed a direct correlation between the increase of fluorescence in the cytoplasm and the increase of the viral antigen. The intensity of the cytoplasm fluorescence was 1.1 to 2.0 times higher in infected cells than that observed in control cells. On the other hand, the intensity of the fluorescence in the cell membrane was similar to that of the non-infected control cells. The Western blotting assay did not allow to establish measurable differences between infected and non-infected MA104 cells, because the increase of the protein are below the detection limit. According to the results of ELISA, HSC70 level increases 1 to 3 times in MA104 cells after (8 h p.i. the infection with strain RRV, whereas infection with strain RF produced an increase which ranged from 1.3 to 2.5 times after 10 h p.i. Infection by strain Wa was correlated with un increase of HSC70 level between 1.7 and 3.0 times after 2 h p.i. Conclusions. The results suggest that the increase of HSC70 accumulation level possibly corresponds to an increased expression of its gene during the rotavirus infection and probably it is involved in rotavirus multiplication steps additional to those of entry and exit processes.

  6. The cultural properties in MA-104 cell and establishment of FQ-PCR diagnostic method for porcine rotavirus%猪轮状病毒的细胞培养特性与FQ-PCR检测方法的建立

    Institute of Scientific and Technical Information of China (English)

    魏锁成; 巩转娣; 宋昌军

    2011-01-01

    To explore isolation conditions and culture properties of rotavirus and establish Real time fluorescence quantitative PCR(FQ-PCR) diagnostic method for porcine rotatirus(PRV).MA-104 cells were cultured in the three mediums to decide the optimum one.The positive fecal samples detected by ELISA in diarrhea piglets were cultured in group C medium 5% CO2 at 37℃.MA-104 cells were inoculated with rotavirus,the rotavirus was isolated and purified, VP6 gene nucleotides of the separated rotavirus strains were sequenced, the homology of VP6 gene was blasted with the standard porcine rotavirus (PRV) strain(AV-55).Real time FQ-PCR diagnostic method for porcine rotatirus has been established.The MA-104 cells pasted wall and grew quickly with low costs when cultured in group C culture medium.the optium culture conditions of rotavirus was 5 % CO2 at 37℃.Cells appeared some clear cytopathic effects (CPE) after 18 h of inoculation,such as cell shrinking and integrating,cell layer splitting, vacuolization and nuclear karyopyknosis ect.The rotaviruss were received when CPE reached 90 %.One rotavirus strains(GSPRV01 strain) was isolated and identified as PRV through VP6 nucleotide sequencing.Its homology was up to 88.50% with PRV reference strains (AV-55).PRV grows well in MA104 at 37℃ and 5%CO2.The homology of GSPRV01 strain is 88.50% with reference strain.FQ-PCR detection methods has been established.%为了探讨动物轮状病毒的细胞培养特性和分离方法,建立FQ-PCR检测方法,旨在为研发诊断试剂盒和疫苗莫定基础.37℃5%CO2下用细胞培养液C培养ELISA检测的阳性猪粪便样本,观察细胞形态的变化;用RV感染MA-104细胞,分离纯化病毒,测定VP6基因序列并分析其同源性,在普通PCR和实时定量PCR的基础上,建立FQ-PCR检测方法.结果,MA-104细胞培养的最佳条件为37℃5%CO2 ;接毒后18 h出现细胞膜缩融合、细胞层裂开、细胞核固缩及空泡化等

  7. Thaw-and-use target cells pre-labeled with calcein AM for antibody-dependent cell-mediated cytotoxicity assays.

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    Chung, Shan; Nguyen, Van; Lin, Yuwen Linda; Kamen, Lynn; Song, An

    2017-08-01

    In vitro antibody-dependent cell-mediated cytotoxicity (ADCC) assays are routinely performed to support the research and development of therapeutic antibodies. In ADCC assays, target cells bound by the antibodies are lysed by activated effector cells following interactions between the Fc region of the bound antibody and Fcγ receptors on effector cells. Target cell lysis is typically measured by quantification of released endogenous enzymes, e.g., lactate dehydrogenase, or measurement of released exogenous labels, e.g., (51)Cr, europium or calcein. ADCC assays based on the detection of exogenous labels released from lysed target cells generally show higher sensitivity and require shorter incubation times. However, target cells are usually labeled immediately prior to assay, which inadvertently introduces additional assay variations due to differences in target cell conditions and labeling/handling processes. In this report, we describe the use of thaw-and-use pre-labeled target cells for ADCC assays. Thaw-and-use target cells in our experiments were pre-labeled with the fluorescent dye calcein AM, cryopreserved in single-use aliquots and used directly in assays after thawing. Upon thaw, the pre-labeled cells displayed viability and label retention comparable to freshly labeled cells, responded to ADCC mediated by both peripheral blood mononuclear cells and engineered natural killer cells, performed stably for at least 3 years and provided favorable precision and accuracy to ADCC assays. Implementation of thaw-and-use pre-labeled target cells in ADCC assays can help to alleviate both cell culture and dye labeling derived variability, increase the flexibility of assay scheduling and improve assay consistency and robustness. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Infectious rotavirus enters cells by direct cell membrane penetration, not by endocytosis

    Energy Technology Data Exchange (ETDEWEB)

    Kaljot, K.T.; Shaw, R.D.; Greenberg, H.B. (Stanford Univ. School of Medicine, CA (USA) Palo Alto Veterans Administration Medical Center, CA (USA)); Rubin, D.H. (Univ. of Pennsylvania, Philadelphia (USA))

    1988-04-01

    Rotaviruses are icosahedral viruses with a segmented, double-stranded RNA genome. They are the major cause of severe infantile infectious diarrhea. Rotavirus growth in tissue culture is markedly enhanced by pretreatment of virus with trypsin. Trypsin activation is associated with cleavage of the viral hemagglutinin (viral protein 3 (VP3); 88 kilodaltons) into two fragments (60 and 28 kilodaltons). The mechanism by which proteolytic cleavage leads to enhanced growth is unknown. To determine whether trypsin treatment affected rotavirus internalization, the authors studied the kinetics of entry of infectious rhesus rotavirus (RRV) into MA104 cells. Trypsin-activated RRV was internalized with a half-time of 3 to 5 min, while nonactivated virus disappeared from the cell surface with a half-time of 30 to 50 min. In contrast to trypsin-activated RRV, loss of nonactivated RRV from the cell surface did not result in the appearance of infection, as measured by plaque formation. Purified trypsin-activated RRV added to cell monolayers at pH 7.4 mediated {sup 51}Cr, ({sup 14}C)choline, and ({sup 3}H)inositol released from prelabeled MA104 cells. This release could be specifically blocked by neutralizing antibodies to VP3. These results suggest that MA104 cell infection follows the rapid entry of trypsin-activated RRV by direct cell membrane penetration. Cell membrane penetration of infectious RRV is initiated by trypsin cleavage of VP3. Neutralizing antibodies can inhibit this direct membrane penetration.

  9. Efflux of radioactive nucleotides from mouse pancreatic islets prelabelled with 2-/sup 3/H-adenosine

    Energy Technology Data Exchange (ETDEWEB)

    Welsh, M.

    1982-07-01

    Cultured mouse pancreatic islets were prelabelled with 2-/sup 3/H-adenosine in order to monitor the efflux pattern of radioactivity and insulin. The outflow of radioactivity decreased continuously when the islets were perifused with glucose (1.67 mmol/l). When raising the glucose concentration to 16.7 mmol/l, there was a prompt inhibition of the radioactive efflux concomitant with an increased rate of insulin release. These effects were reversed when the high glucose challenge was withdrawn. Similar radioactive efflux patterns were obtained after addition of ..cap alpha..-ketoisocaproic acid, leucine or pyruvate to the perifusion medium, and also when the islets were challenged with high glucose concentrations in the absence of calcium. Both antimycin A and glipizide stimulated the efflux of radioactivity, although only the addition of glipizide was accompanied by a stimulation of the insulin release. Nucleotides constituted approximately 90% of the total effluent radioactivity. Decrease in the radioactive AMP and ADP efflux due to high glucose was furthermore found to be the cause of the observed inhibition of the total radioactive efflux. The changes in radioactive efflux induced by glucose probably reflect changes in the intracellular concentrations of AMP and ADP. It is concluded that no simple correlation exists between radioactive efflux and insulin release and that changes in the intracellular concentrations of nucleotides may be an early event in the stimulus-secretion coupling of glucose-induced insulin release.

  10. Effects of acetylcholine and other agents on /sup 32/P-prelabeled phosphoinositides and phosphatidate in crude synaptosomal preparations

    Energy Technology Data Exchange (ETDEWEB)

    White, H.L.

    1988-05-01

    Experimental conditions are described which permit effects of various agents on polyphosphoinositides and phosphatidic acid (PA) to be evaluated simultaneously in crude nerve-ending preparations from rat brain. Acetylcholine (3-100 microM) or carbachol (30-1,000 microM) induced the hydrolysis of prelabeled polyphosphoinositides and, at the same time, stimulated the net label incorporated in phosphatidic acid. All muscarinic effects were blocked by atropine or pirenzepine. Non-muscarinic agonists (glutamate, adenosine, norepinephrine) stimulated polyphosphoinositide hydrolysis in this preparation, but of these only norepinephrine affected phosphatidic acid turnover. A potentiation of acetylcholine-induced phosphoinositide turnover by KCl was observed, as well as an apparent selective inhibition of PIP2 hydrolysis by LiCl. Acetylcholine-stimulated turnover of PA was not necessarily coupled to phosphoinositide hydrolysis.

  11. The effect of concanavalin A on the replication of rotavirus (SA-11 in cell culture

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    Hasenack Beatriz S.

    2002-01-01

    Full Text Available Rotavirus (RV strain SA-11 was studied with respect to its infectivity in MA-104 cell cultures and the effect of concanavalin A (ConA. Receptors for ConA at the surface of MA-104 cell were determined by fluorescence assay and specifically inhibited by D-mannose. The kinetics of virus growth was carried out by plaque assay. Electron microscopy and polyacrylamide gel electrophoresis were used for monitoring the experiments. It was concluded that RV replication was not affected consistently by ConA, however it interfered with the development of cytopathic effect (CPE without altering virus yields.

  12. PHA-induced cytotoxicity of human lymphocytes against adherent hela-cells

    NARCIS (Netherlands)

    Huges-Law, G.; de Gast, G. C.; The, T. Hauw

    1978-01-01

    The conditions for a phytohaemagglutinin(PHA)-induced cytotoxicity test of human peripheral blood lymphocytes were investigated. [3H]thymidine prelabelled HeLa cells were used as target cells. Stimulation with 10 μl PHA/ml during 24 h gave the best measure of lymphocyte cytotoxic capacity. Supernata

  13. Arginine-vasopressin stimulates the formation of phosphatidic acid in rat Leydig cells

    DEFF Research Database (Denmark)

    Nielsen, J.R.; Hansen, Harald S.; Jensen, B.

    1987-01-01

    Arginine-vasopressin (AVP) stimulated the formation of labelled phosphatidic acid (PA) in [C]arachidonic acid-prelabelled rat Leydig cells. After addition of 10 M AVP [C]arachidonoylphosphatidic acid reached a maximum within 2 min. The increase was dose-dependent (10-10 M). No change in labelling...

  14. Susceptibility of various cell lines to Neospora caninum tachyzoites cultivation

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    Khordadmehr, M.,

    2014-05-01

    Full Text Available Neospora caninum is a coccidian protozoan parasite which is a major cause of bovine abortions and neonatal mortality in cattle, sheep, goat and horse. Occasionally, cultured cells are used for isolation and multiplication of the agent in vitro with several purposes. In this study the tachyzoite yields of N. caninum were compared in various cell cultures as the host cell lines. Among the cell cultures tested, two presented good susceptibility to the agent: cell lines Vero and MA-104. SW742 and TLI (in vitro suspension culture of lymphoid cells infected with Theileria lestoquardi showed moderate sensitivity. No viable tachyzoite were detected in the culture of MDCK and McCoy cell lines. These results demonstrate that MA-104 and SW742 cells present adequate susceptibility to N. caninum compared to Vero cells, which have been largely used to multiply the parasite in vitro. Moreover, these have easy manipulation, fast multiplication and relatively low nutritional requirements. In addition, the result of this study showed that TLI cell line as a suspension cell culture is susceptible to Nc-1 tachyzoites infection and could be used as an alternative host cell line for tachyzoites culture in vitro studies.

  15. Simple and sensitive method for monitoring drug-induced cell injury in cultured cells

    Energy Technology Data Exchange (ETDEWEB)

    Shirhatti, V.; Krishna, G.

    1985-06-01

    A simple, sensitive method has been developed for evaluating cell injury noninvasively in monolayer cells in culture. The cell ATP pool was radiolabeled by incubating the cells with (/sup 14/C)adenine. The uptake and incorporation of (/sup 14/C)adenine was shown to proportional to the number of cells. As determined by HPLC, about 65-70% of the incorporated /sup 14/C label was in the ATP pool, 15-20% was in the ADP pool, and the rest was in the 5'-AMP pool. When prelabeled cells were exposed to toxic drugs (acetaminophen, calcium ionophore A-23187, or daunomycin) there was a marked decrease in cell ATP with a concomitant increase in leakage of labeled nucleotides, mainly 5'-AMP and 5'IMP. The authors have shown that leakage of /sup 14/C label into the medium from the prelabeled cells may be employed for quantitation of cell injury. This new measure of toxicity was shown to correlate very well with LDH leakage from the cells, which is a well accepted measure of cell injury. The leakage of 5'-(/sup 14/C)AMP also correlated very well with the reduction of cell ATP in cardiac myocytes. This method has been used for monitoring drug-induced toxicity in liver cells, cardiac myocytes, and LB cells.

  16. Meniscus reconstruction through coculturing meniscus cells with synovium-derived stem cells on small intestine submucosa--a pilot study to engineer meniscus tissue constructs.

    Science.gov (United States)

    Tan, Yunbing; Zhang, Yuanyuan; Pei, Ming

    2010-01-01

    The purpose of this study was to investigate the feasibility of coculturing meniscus cells (MCs) and synovium-derived stem cells (SDSCs) on small intestine submucosa (SIS) to establish an innovative method to engineer in vitro meniscus constructs. About 0.9 million cells (MCs, prelabeled SDSCs [with Vybrant DiI], and a coculture of MCs and prelabeled SDSCs [50:50]) were mixed with fibrin gel and seeded onto freeze-dried SIS discs (5 mm diameter x 1-2 mm thickness) individually. The tissue constructs were incubated in a serum-free defined medium supplemented with 10 ng/mL transforming growth factor beta-1 and 500 ng/mL insulin-like growth factor I for 1 month. One day after cell seeding, samples for scanning electron microscopy were prepared to evaluate cell attachment on the SIS surface. During incubation, fluorescent microscopy was used to trace cell migration (with 4',6-diamidino-2-phenylindole as a counterstain) on SIS scaffold. The tissue constructs were assessed using histology, immunostaining, biochemical analysis, real-time polymerase chain reaction, and compressive modulus. All three groups of cells attached well on SIS. The coculture with SDSCs yielded MC-based tissue constructs with greater cell survival and differentiation into chondrogenic phenotypes, which exhibited higher glycosaminoglycan, collagen II, and Sox 9 but relatively low collagen I, resulting in the concomitant increase in equilibrium modulus. This pilot study demonstrates the advantages of coculturing MCs with SDSCs on SIS for meniscus tissue engineering and regeneration.

  17. CELL DETACHMENT BY PROLYL-SPECIFIC ENDOPEPTIDASE FROM WOLFIPORIA COCOS

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    Katharina Cierpka

    2014-01-01

    Full Text Available As requirements for Advanced Therapy Medicinal Product (ATMP production differ from other production processes (e.g., therapeutic protein production, cell detachment is often a crucial step for the process success. In most cases, cell detachment is done enzymatically. Although many peptidases are established in cell culture in R&D, e.g., Trypsin as gold standard, many of them seem to be unsuitable in ATMP production processes. Therefore, the present study investigated a novel endopeptidase used in food biotechnology for its applicability in ATMP processes where cell detachment is needed. The Prolyl-specific Peptidase (PsP is of non-mammalian origin and considered as safe for humans. PsP was purified from the supernatant of the fungus Wolfiporia cocos. The isolation and purification resulted in an enzyme solution with 0.19 U mg-1 prolyl-specific activity. By in silico analysis it was confirmed that attachment-promoting proteins can be cleaved by PsP in a similar amount than with Trypsin. Further the proteolytic activity was determined for PsP and Trypsin by using the same enzymatic assay. Detachment with both enzymes was compared for cells used in typical therapeutic production processes namely a mesenchymal stem cell line (hMSC-TERT as a model for a cell therapeutic, Vero and MA104 cells used for viral therapeutic or vaccine production. The cell detachment experiments were performed with comparable enzyme activities (1.6 U mL-1. hMSC-TERT detachment was faster with PsP than with Trypsin. For Vero cells the detachment with PsP was not only faster but also more efficient. For MA104 cells the detachment rate with PsP was similar to Trypsin. For all cell types, detachment with PsP showed less influence on cell growth and metabolism compared to standard Trypsin.Thus, three cell types used in ATMP, viral therapeutics or vaccine production can be detached efficiently and gently with PsP. Therefore, PsP shows

  18. Salivary gland homeostasis is maintained through acinar cell self-duplication.

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    Aure, Marit H; Konieczny, Stephen F; Ovitt, Catherine E

    2015-04-20

    Current dogma suggests that salivary gland homeostasis is stem cell dependent. However, the extent of stem cell contribution to salivary gland maintenance has not been determined. We investigated acinar cell replacement during homeostasis, growth, and regeneration, using an inducible CreER(T2) expressed under the control of the Mist1 gene locus. Genetic labeling, followed by a chase period, showed that acinar cell replacement is not driven by the differentiation of unlabeled stem cells. Analysis using R26(Brainbow2.1) reporter revealed continued proliferation and clonal expansion of terminally differentiated acinar cells in all major salivary glands. Induced injury also demonstrated the regenerative potential of pre-labeled acinar cells. Our results support a revised model for salivary gland homeostasis based predominantly on self-duplication of acinar cells, rather than on differentiation of stem cells. The proliferative capacity of differentiated acinar cells may prove critical in the implementation of cell-based strategies to restore the salivary glands.

  19. Multimodality Molecular Imaging of Cardiac Cell Transplantation: Part II. In Vivo Imaging of Bone Marrow Stromal Cells in Swine with PET/CT and MR Imaging.

    Science.gov (United States)

    Parashurama, Natesh; Ahn, Byeong-Cheol; Ziv, Keren; Ito, Ken; Paulmurugan, Ramasamy; Willmann, Jürgen K; Chung, Jaehoon; Ikeno, Fumiaki; Swanson, Julia C; Merk, Denis R; Lyons, Jennifer K; Yerushalmi, David; Teramoto, Tomohiko; Kosuge, Hisanori; Dao, Catherine N; Ray, Pritha; Patel, Manishkumar; Chang, Ya-Fang; Mahmoudi, Morteza; Cohen, Jeff Eric; Goldstone, Andrew Brooks; Habte, Frezghi; Bhaumik, Srabani; Yaghoubi, Shahriar; Robbins, Robert C; Dash, Rajesh; Yang, Phillip C; Brinton, Todd J; Yock, Paul G; McConnell, Michael V; Gambhir, Sanjiv S

    2016-09-01

    Purpose To quantitatively determine the limit of detection of marrow stromal cells (MSC) after cardiac cell therapy (CCT) in swine by using clinical positron emission tomography (PET) reporter gene imaging and magnetic resonance (MR) imaging with cell prelabeling. Materials and Methods Animal studies were approved by the institutional administrative panel on laboratory animal care. Seven swine received 23 intracardiac cell injections that contained control MSC and cell mixtures of MSC expressing a multimodality triple fusion (TF) reporter gene (MSC-TF) and bearing superparamagnetic iron oxide nanoparticles (NP) (MSC-TF-NP) or NP alone. Clinical MR imaging and PET reporter gene molecular imaging were performed after intravenous injection of the radiotracer fluorine 18-radiolabeled 9-[4-fluoro-3-(hydroxyl methyl) butyl] guanine ((18)F-FHBG). Linear regression analysis of both MR imaging and PET data and nonlinear regression analysis of PET data were performed, accounting for multiple injections per animal. Results MR imaging showed a positive correlation between MSC-TF-NP cell number and dephasing (dark) signal (R(2) = 0.72, P = .0001) and a lower detection limit of at least approximately 1.5 × 10(7) cells. PET reporter gene imaging demonstrated a significant positive correlation between MSC-TF and target-to-background ratio with the linear model (R(2) = 0.88, P = .0001, root mean square error = 0.523) and the nonlinear model (R(2) = 0.99, P = .0001, root mean square error = 0.273) and a lower detection limit of 2.5 × 10(8) cells. Conclusion The authors quantitatively determined the limit of detection of MSC after CCT in swine by using clinical PET reporter gene imaging and clinical MR imaging with cell prelabeling. (©) RSNA, 2016 Online supplemental material is available for this article.

  20. Progenitor cells from the porcine neural retina express photoreceptor markers after transplantation to the subretinal space of allorecipients

    DEFF Research Database (Denmark)

    Klassen, Henry; Kiilgaard, Jens Folke; Zahir, Tasneem

    2007-01-01

    and rhodopsin. In addition, reverse transcription-polymerase chain reaction showed expression of the transcription factors Dach1, Hes1, Lhx2, Pax6, Six3, and Six6. Progenitor cells prelabeled with vital dyes survived as allografts in the subretinal space for up to 5 weeks (11 of 12 recipients) without exogenous......Work in rodents has shown that cultured retinal progenitor cells (RPCs) integrate into the degenerating retina, thus suggesting a potential strategy for treatment of similar degenerative conditions in humans. To demonstrate the relevance of the rodent work to large animals, we derived progenitor...... cells from the neural retina of the domestic pig and transplanted them to the laser-injured retina of allorecipients. Prior to grafting, immunocytochemical analysis showed that cultured porcine RPCs widely expressed neural cell adhesion molecule, as well as markers consistent with immature neural cells...

  1. 多细胞株微量培养法在病毒性脑炎、脑膜炎患儿病原学检测的应用研究%Microculture of multiple cell lines to detect pathogens responsible for viral encephalitis and meningitis

    Institute of Scientific and Technical Information of China (English)

    王世富; 张乐海; 王素兰; 蒋芙蓉; 于凤玲

    2012-01-01

    目的 探讨多细胞株微量培养法在病毒性脑炎、脑膜炎病原学检测中的应用价值.方法 将脑脊液(CSF)标本过滤除菌后分别接种于含有青霉素和链霉素微量细胞培养板单层细胞上,每份标本平行接种8株细胞:MA104、MDCK、HEL、HEK293、Vero、Hep-2、Hela和BHK-21.静置培养,获得稳定的病毒株.以肠道病毒(EV)组合血清鉴定引起病毒性脑炎、脑膜炎的常见病毒类型.结果 126份病毒性脑炎、脑膜炎患儿CSF标本82份分离到病毒,阳性率63.0%,其中MA104阳性率为57.1%,MDCK阳性率为19.8%,HEL阳性率为11.9%,HEK阳性率为7.1%,Vero阳性率为6.3%,Hep-2阳性率为4.8%,Hela阳性率为4.0%,BHK-21阳性率为2.4%.病变细胞经血清学鉴定,78例鉴定出病毒株,鉴定率为92.8%,这些病毒中EV所占比例较高,为69.2%;ADV占11.5%,HSV-Ⅰ占5.1%,HSV-Ⅱ占6.4%;CMV占5.1%,INF占2.6%.结论 MA104细胞是分离CSF中病毒较敏感的细胞,可以作CSF中病原分离的首选细胞;联合多株细胞可提高细胞病变检出率.多株细胞微孔板培养法分离CSF病毒具有推广应用价值.%Objective To explore the use of microculture of multiple cell lines to detect pathogens responsible for viral encephalitis and meningitis. Methods Cerebrospinal fluid (CSF) specimens were aseptically filtered and plated on mi-croporous plates in single cell layers containing penicillin and streptomycin. Each plate was seeded in parallel with eight types of cells: MA104, MDCK, HEL, HEK293, Vero, Hep-2, Hela, and BHK-21. After static culturing, stable strains were obtained. Serum containing Enterovirus (EV) was used to identify the common pathogens responsible for viral encephalitis and meningitis. Results Viruses were isolated in specimens from 82 (63.0%) of 126 children with viral encephalitis or meningitis. Of the children, 57.1% tested positive for MA104, 19. 8% tested positive for MDCK, tested positive for HEL was 11. 9

  2. Investigation of the Cell Surface Proteome of Human Periodontal Ligament Stem Cells

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    Jimin Xiong

    2016-01-01

    Full Text Available The present study examined the cell surface proteome of human periodontal ligament stem cells (PDLSC compared to human fibroblasts. Cell surface proteins were prelabelled with CyDye before processing to extract the membrane lysates, which were separated using 2D electrophoresis. Selected differentially expressed protein “spots” were identified using Mass spectrometry. Four proteins were selected for validation: CD73, CD90, Annexin A2, and sphingosine kinase 1 previously associated with mesenchymal stem cells. Flow cytometric analysis found that CD73 and CD90 were highly expressed by human PDLSC and gingival fibroblasts but not by keratinocytes, indicating that these antigens could be used as potential markers for distinguishing between mesenchymal cells and epithelial cell populations. Annexin A2 was also found to be expressed at low copy number on the cell surface of human PDLSC and gingival fibroblasts, while human keratinocytes lacked any cell surface expression of Annexin A2. In contrast, sphingosine kinase 1 expression was detected in all the cell types examined using immunocytochemical analysis. These proteomic studies form the foundation to further define the cell surface protein expression profile of PDLSC in order to better characterise this cell population and help develop novel strategies for the purification of this stem cell population.

  3. Recycling of resting cells in the JB-1 ascites tumour after treatment with 1-beta-D-arabinofuranosylcytosine (ara-C).

    Science.gov (United States)

    Dombernowsky, P; Bichel, P

    1976-01-01

    Resting cells in tumours present a major problem in cancer chemotherapy. In the plateau phase of grwoth of the murine JB-1 ascites tumour (i.e. 10 days after 2-5 X 10(6) cells i.p.) large fractions of non-cycling cells with G1 and G2 DNA content (Q1 and Q2 cells) are present, and the fate of these resting cells was investigated after treatment with 1-beta-D-arabinofuranosylcytosine (Ara-C). The experimental work of growth curves, percentage of labelled mitoses curves after continuous labelling with 3H-TdR, and cytophotometric determination of single-cell DNA content in unlabelled tumour cells. Treatment with an i.p. single injection of Ara-C 200 mg/kg in the plateau JB-1 tumour resulted in a significant reduction in the number of tumour cells 1 and 2 days later as compared with untreated controls, while no difference in the number of tumour cells was observed after 3 days. In tumours prelabelled with 3H-TdR 24 hr before Ara-C treatment, a significant decrease in the percentage of labelled mitoses was observed 6-8 hr later followed by a return to the initial value after 12 hr, and a new pronounced fall from 20 hr after Ara-C. The second fall in the percentage of labelled mitoses disappeared when the labelling with 3H-TdR was continued also after Ara-C treatment. Cytophotometry of unlabelled tumour cells prelabelled for 24 hr with 3H-TdR before Ara-C treatment showed 20 hr after Ara-C a pronounced decrease in the fraction of Q1 cells paralleled by an increase in the fraction of unlabelled cells with S DNA content. The results indicate recycling of resting cells first with G2 and later with G1 DNA content, which contribute to the regrowth of the tumours.

  4. [Use of cell culture for the research of cytotoxic and antiviral effects of a natural extract of Amaryllidaceae].

    Science.gov (United States)

    Husson, G P; Vilagines, P; Sarrette, B; Vilagines, R

    1995-01-01

    The use of tissue culture for evaluation of antiviral agents can provide rapid information on the toxicity induced by drugs. Toxicity is assessed through 4 different tests: observation through a light microscope, colorimetric evaluation of living cells stained with MTT (Methyl Thiazol Tetrazolium), colorimetric evaluation of fixed cells stained with crystal violet, inhibition of incorporation of radioactive labelled precursors specific to the synthesis under study. These tests allowing evaluation of effects on cell morphological changes (1), of modifications of mitochondrial and enzymatic activities in the cytoplasm (2), of effects on cell growth (3) and on their major synthesis [ADN, ARN, proteins] (4). This design of experiments has been applied to an hydroalcoolic extract from Haemanthus albiflos (Amaryllidaceae) tested for its antiviral properties towards Poliovirus type 1 propagated on monkey kidney cells line (MA 104). The maximum tolerated dose by the cell and the inhibition of virus replication were determined according to tests 2 and 3. The sensitive step of the virus replication cycle was investigated using test 4. Concentration of 7 microliters/ml plant extract showed: 20% cytotoxicity (MTT test). At 7 microliters/ml plant extract the inhibition of replication virus is 4.5 log units (microplates assay) and inhibition of proteins viral synthesis is 97% compared with the control.

  5. Cytotoxic Effect of Lipophilic Bismuth Dimercaptopropanol Nanoparticles on Epithelial Cells.

    Science.gov (United States)

    Rene, Hernandez-Delgadillo; Badireddy, Appala Raju; José, Martínez-Sanmiguel Juan; Francisco, Contreras-Cordero Juan; Israel, Martinez-Gonzalez Gustavo; Isela, Sánchez-Nájera Rosa; Chellam, Shankararaman; Claudio, Cabral-Romero

    2016-01-01

    Bismuth nanoparticles have many interesting properties to be applied in biomedical and medicinal sectors, however their safety in humans have not been comprehensively investigated. The objective of this research was to determine the cytotoxic effect of bismuth dimercaptopropanol nanoparticles (BisBAL NPs) on epithelial cells. The nanoparticles are composed of 18.7 nm crystallites on average and have a rhombohedral structure, agglomerating into chains-like or clusters of small nanoparticles. Based on MTT viability assay and fluorescence microscopy, cytotoxicity was not observed on monkey kidney cells after growing with 5 µM of BisBAL NPs for 24 h. Employing same techniques, identical results were obtained with human epithelial cells (HeLa), showing a not strain-dependent phenomenon. The absence of toxic effects on epithelial cells growing with BisBAL NPs was corroborated with long-time experiments (24-72 hrs.), showing no difference in comparison with growing control (cells without nanoparticles). Further, genotoxicity assays, comet assay and fluorescent microscopy and electrophoresis in bromide-stained agarose gel revealed no damage to genomic DNA of MA104 cells after 24 h. of exposition to BisBAL NPs. Finally, the effect of bismuth nanoparticles on protein synthesis was studied in cells growing with BisBAL NPs for 24 h. SDS-PAGE assays showed no difference between treated and untreated cells, suggesting that BisBAL NPs did not interfere with protein synthesis. Hence BisBAL NPs do not appear to exert cytotoxic effects suggesting their biological compatibility with epithelial cells.

  6. Pathogenic Trichomonas vaginalis cytotoxicity to cell culture monolayers.

    Science.gov (United States)

    Alderete, J F; Pearlman, E

    1984-04-01

    Exposure of monolayer cultures of human urogenital and vaginal (HeLa), human epithelial (HEp-2), normal baboon testicular (NBT), and monkey kidney (Vero) cells to live pathogenic Trichomonas vaginalis resulted in extensive disruption of monolayers. Trypan blue was taken up by all host cells released from cell monolayers, which indicated irreversible damage of these cell types by trichomonads. Time and dose related data on cytotoxicity kinetics were obtained using increasing ratios of parasites to cells. All cell types were most sensitive to trichomonads at a multiplicity of infection of one. Release of tritiated thymidine (3H-thymidine) of the deoxyribonucleic acid (DNA) of prelabelled host cells after incubation with T vaginalis corroborated that extensive cytotoxicity was caused by pathogenic trichomonads in man. Only living parasites were cytotoxic, and no trichomonal toxic products were implicated in disruption of the cell monolayer cultures. A pathogenic bovine trichomonad, Tritrichomonas foetus KV-1, produced half as much cell damage as did T vaginalis. Trichomonas tenax, a non-pathogenic member of the normal flora of the oral cavity in man, produced no measurable cytotoxicity to HeLa cells when compared with the pathogenic human trichomonads.

  7. Activation of phospholipase D activity in transforming growth factor—beta—induced cell growth inhibition

    Institute of Scientific and Technical Information of China (English)

    ZHOUBINGHONG; JUNSONGCHEN; 等

    2000-01-01

    Cells regulate phospholipase D(PLD) activity in response to numerous extracellular signals.Here,we investigated the involvement of PLD activity in transforming growth factor-β(TGF-β1)-mediated growth inhibition of epithelial cells.TGF-β1)-mediated growth inhibition of epithelial cells.TGF-β1 inhibits the growth of MDCK,Mv1Lu,and A-549 cells.In the presence of 0.4% butanol,TGF-β1 induces an increase in the formation of phosphatidylbutanol,a unique product catalyzed by PLD.TGF-β1 also induces an increase in phosphatidic acid (PA) level in A-549 and MDCK cells.TGF-β1 induces an increase in the levels of DAG labeled with [3H]-myristic acid in A-549 and MDCK cells but not in Mv1Lu cells.No increase of DAG was observed in cells prelabeled with [3H]-arachidonic acid.The data presented suggest that PLD activation is involved in the TGF-β1-induced cell growth inhibition.

  8. Purification of neuropathy target esterase from avian brain after prelabelling with [3H]diisopropyl phosphorofluoridate.

    Science.gov (United States)

    Rüffer-Turner, M E; Read, D J; Johnson, M K

    1992-01-01

    Neuropathy target esterase from hen brains was radiolabelled at the active site with [3H]diisopropyl phosphorofluoridate. The labelled protein was purified by differential centrifugation and Nonidet P40 solubilization, detergent phase partitioning, anion exchange, and preparative sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The volatilizable counts assay and analytical SDS-PAGE were used to monitor the protein. The 150-kDa subunit polypeptide appears as a single band on analytical SDS-PAGE.

  9. Acetylcholine increases the breakdown of triphosphoinositide of rabbit iris muscle prelabelled with [32P] phosphate.

    Science.gov (United States)

    Abdel-Latif, A A; Akhtar, R A; Hawthorne, J N

    1977-01-15

    1. Paired iris smooth muscles from rabbits were incubated for 30 min at 37 degrees C in an iso-osmotic salt medium containg glucose, inositol, cytidine and [32P]phosphate. 2. One of the pair was then incubated at 37 degrees C for 10 min in unlabelled medium containing 10mM-2-deoxyglucose and the other was incubated in the presence of acetylcholine plus eserine (0.05mM each). 2-Deoxyglucose, which was included in the incubation medium to minimize the biosynthesis of triphosphoinositide from ATP and diphosphoinositide, decreased the amount of labelled ATP by 71% and inhibited further 32P incorporation from ATP into triphosphoinositide by almost 30%. 3. Acetylcholine (0.05mM) increased significantly the loss of 32P from triphosphoinositide (the 'triphosphoinositide effect') in 32P-labelled iris muscle. This effect was measured both chemically and radiochemically. It was also observed when 32Pi was replaced by myo-[3H]inositol in the incubation medium. 4. The triphosphoinositide effect was blocked by atropine but not by D-tubocurarine. Further, muscarinic but not nicotinic agonists were found to provoke this effect. 5. Acetylcholine decreased by 28% the 32P incorporation into triphosphoinositide, presumably by stimulating its breakdown. This decrement in triphosphoinositide was blocked by atropine, but not by D-tubocurarine. 6. The triphosphoinositide effect was accompanied by a significant increase in 32P labelling, but not tissue concentration, of phosphatidylinositol and phosphatidic acid. The possible relationship between the loss of 32P label from triphosphoinositide in response to acetylcholine and the concomitant increase in that of phosphatidylinositol and phosphatidic acid is discussed. 7. The presence of triphosphoinositide phosphomonoesterase, the enzyme that might be stimulated in the iris smooth muscle by the neurotransmitter, was demonstrated, and, under our methods of homogenization and assay, more than 80% of its activity was localized in the particulate fraction.

  10. Effect of cell culture system on the production of human viral antigens Efeito do sistema de cultura celular na produção de antígenos virais humanos

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    Ronaldo Zucatelli Mendonça

    2004-06-01

    Full Text Available A comparative study was performed in the production of different viral antigens by using microcarrier systems and traditional systems. Vero, BHK and MA 104 cells were cultivated in microcarriers (2mg/ml using a bioreactor with a working capacity of 3.7 liters, in parallel with conventional Roux bottles. After four days (BHK cells, and seven days of culture (Vero and MA-104 cells, the cells were infected with 0.1 MOI (multiplicity of infection of rabies virus, measles virus, poliovirus and rotavirus. The yields of the cells and virus in microcarriers and in the conventional system were determined. It was observed that in the microcarrier system, an average increase of twenty-fold more cells/ml was obtained in relation to the conventional monolayer culture, using Roux bottle. On the other hand, cells grown in Roux bottles presented 1.3 to 6.7 more viruses/ml culture than those in the microcarrier systems. However, the overall data showed that yieldings, in terms of viruses per batch, were statistically similar for both systems (p > 0.05. The amount of viral antigen production seems to depend not only on cell concentration, but also on other culture factors such as the characteristic of the cell-growth surface. Thus, the present findings provide a baseline for further improvements and strategies to be established for a scaling-up virus production since depending on the type of virus the optimal conditions found for a small-scale virus production seem unsuitable for large-scale production, requiring new standardization and evaluation.Foi realizado estudo comparativo na produção de diferentes antígenos virais usando sistema de microcarregador e sistema tradicional. Células Vero, BHK e MA-104 foram cultivadas em microcarregadores (2mg/ml utilizando-se biorreatores com capacidade de 3,7 litros e, em paralelo, no sistema convencional com garrafas Roux. Após quatro dias de cultura para as células BHK e sete dias para as células Vero e MA-104, as c

  11. In vitro ozone exposure increases release of arachidonic acid products from a human bronchial epithelial cell line

    Energy Technology Data Exchange (ETDEWEB)

    McKinnon, K.P.; Madden, M.C.; Noah, T.L.; Devlin, R.B. (TRC Environmental Corporation, Chapel Hill, NC (United States))

    1993-02-01

    Eicosanoids released after ozone exposure of a human bronchial epithelial cell line, BEAS-S6, were analyzed by high-pressure liquid chromatography (HPLC) of supernatants from exposed cells prelabeled with [3H]arachidonic acid. BEAS cells released thromboxane B2 (TxB2), prostaglandin E2 (PGE2), leukotriene C4 (LTC4), LTD4, LTE4, and 12-hydroxyheptadecatrienoic acid (HHT) after exposure to ozone at concentrations of 0.1, 0.25, 0.5, and 1.0 ppm. The eicosanoids were identified by coelution with authentic standards. The largest product from ozone-exposed BEAS cells was the most polar peak, designated Peak 1. Release of cyclooxygenase products such as TxB2, PGE2, and HHT was inhibited by acetylsalicylic acid. Peaks that migrated with authentic standards for LTB4, LTC4, and LTD4 were inhibited by the lipoxygenase inhibitor nordihydroguaiaretic acid. The leukotrienes LTB4 and LTC4/D4 could also be detected by immunoassay of concentrated peak fractions. Thus BEAS cells released eicosanoids from cyclooxygenase and lipoxygenase pathways of arachidonic acid metabolism following exposure to ozone. Airway epithelial cells may be an important source of eicosanoids following ozone stimulation in humans.

  12. Characterization of cAMP accumulation mediated by three α1—adrenoceptor subtypes in HEK293 cells

    Institute of Scientific and Technical Information of China (English)

    SONGYao; HUANGYan; DongEr-Dan; HANQi-De; ZHANGYou-Yi

    2003-01-01

    AIM:To investigate the characterization of cAMP response mediated by α1-adrenoceptor (α1-AR) subtypes in HEK293 cells. METHODS:(1) Full-length cDNA encoding three α1-AR subtypes were transfected into HEK293 cells by the calcium phosphate precipitation method, respectively. (2) The densities of α1-AR subtypes expressed in HEK293 cells were measured by radioligand binding assay. (3)cAMP accumulation was measured by [3H] adenine prelabeling method. RESULTS: (1)Activation of each of three subtypes resulted in an increase of cAMP accumulation in HEK293 cells in a dose-dependent manner, which was inhibited by selective α1-AR antagonist prazosin. (2) Comparing the pharmacological property, the maximal responses of α1A-AR to agonists were the most potent, while the sensitivity of α1-AR subtypes to norepinephrine(NE) was the highest. CONCLUSION: Each of three α1-AR subtypes can mediate cAMP accumulation in HEK293 cell line, and there are differences in pharmacological property.

  13. Transplanted bone marrow stem cells relocate to infarct penumbra and co-express endogenous proliferative and immature neuronal markers in a mouse model of ischemic cerebral stroke

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    Liu Wei

    2010-10-01

    Full Text Available Abstract Background Several studies demonstrate that neurogenesis may be induced or activated following vascular insults, which may be important for neuronal regeneration and functional recovery. Understanding the cellular mechanism underlying stroke-associated neurogenesis is of neurobiological as well as neurological/clinical relevance. The present study attempted to explore potential homing and early development of transplanted bone marrow stem cells in mouse forebrain after focal occlusion of the middle cerebral artery, an experimental model of ischemic stroke. Results Bone marrow stem cells isolated from donor mice were confirmed by analysis of surface antigen profile, and were pre-labeled with a lipophilic fluorescent dye PKH26, and subsequently transfused into recipient mice with middle cerebral artery coagulation. A large number of PKH26-labeled cells were detected surrounding the infarct site, most of which colocalized with immunolabelings for the proliferating cell nuclear antigen (PCNA and some also colocalized with the immature neuronal marker doublecortin (DCX during 1-2 weeks after the bone marrow cells transfusion. Conclusions The present study shows that transplanted bone morrow cells largely relocate to the infarct penumbra in ischemic mouse cerebrum. These transplanted bone marrow cells appear to undergo a process of in situ proliferation and develop into putative cortical interneurons during the early phase of experimental vascular injury.

  14. Experimental pathways towards developing a rotavirus reverse genetics system: synthetic full length rotavirus ssRNAs are neither infectious nor translated in permissive cells.

    Directory of Open Access Journals (Sweden)

    James E Richards

    Full Text Available At present the ability to create rationally engineered mutant rotaviruses is limited because of the lack of a tractable helper virus-free reverse genetics system. Using the cell culture adapted bovine RV RF strain (G6P6 [1], we have attempted to recover infectious RV by co-transfecting in vitro transcribed ssRNAs which are identical in sequence to the positive sense strand of each of the 11 dsRNA genomic segments of the RF strain. The RNAs were produced either from cDNAs cloned by a target sequence-independent procedure, or from purified double layered RV particles (DLPs. We have validated their translational function by in vitro synthesis of (35S-labelled proteins in rabbit reticulocyte lysates; all 11 proteins encoded by the RV genome were expressed. Transfection experiments with DLP- or cDNA-derived ssRNAs suggested that the RNAs do not act independently as mRNAs for protein synthesis, once delivered into various mammalian cell lines, and exhibit cytotoxicity. Transfected RNAs were not infectious since a viral cytopathic effect was not observed after infection of MA104 cells with lysates from transfected cells. By contrast, an engineered mRNA encoding eGFP was expressed when transfected under identical conditions into the same cell lines. Co-expression of plasmids encoding NSP2 and NSP5 using a fowlpox T7 polymerase recombinant virus revealed viroplasm-like structure formation, but this did not enable the translation of transfected RV ssRNAs. Attempts to recover RV from ssRNAs transcribed intracellularly from transfected cDNAs were also unsuccessful and suggested that these RNAs were also not translated, in contrast to successful translation from a transfected cDNA encoding an eGFP mRNA.

  15. Phosphatidylethanolamine turnover is an early event in the response of NB sub 2 lymphoma cells to prolactin

    Energy Technology Data Exchange (ETDEWEB)

    Hafez, M.M.; Costlow, M.E. (St. Jude Children' s Research Hospital, Memphis, TN (United States))

    1989-09-01

    The effect of prolactin on phospholipid metabolism in the prolactin-dependent rat lymphoma cell line Nb{sub 2} was investigated in cells prelabeled with ({sup 3}H)arachidonic acid or ({sup 3}H)ethanolamine. Prolactin (20 ng/ml) caused (a) a 20-60% loss of radiolabeled phosphatidylethanolamine within 0.5 to 2 min, (b) a loss of ({sup 3}H)ethanolamine-labeled phosphatidylethanolamine from crude membranes, (c) a rapid accumulation of ({sup 3}H) phosphoethanolamine and ({sup 3}H)ethanolamine, and (d) a transient increase (15 s to 2 min) in prostaglandin F{sub 2}{alpha}, and E{sub 2}. Arachidonic acid (1-2 {mu}g/ml) induced Nb{sub 2} cell growth but prostaglandin F{sub 2}{alpha}, E{sub 2}, ethanolamine, and phosphoethanolamine did not. Prostaglandin E{sub 2} inhibited while prostaglandin F{sub 2}{alpha} enhanced growth in the presence of prolactin or arachidonic acid. These results suggest that stimulation of Nb{sub 2} cell growth by prolactin linked to activation of a phosphatidylethanolamine-specific phospholipase C. Arachidonic acid and prostaglandin F{sub 2}{alpha} may participate in regulating the mitogenic actin of prolactin.

  16. Acrolein stimulates eicosanoid release from bovine airway epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Doupnik, C.A.; Leikauf, G.D. (Univ. of Cincinnati College of Medicine, OH (USA))

    1990-10-01

    Injury to the airway mucosa after exposure to environmental irritants is associated with pulmonary inflammation and bronchial hyperresponsiveness. To better understand the relationships between mediator release and airway epithelial cell injury during irritant exposures, we studied the effects of acrolein, a low-molecular-weight aldehyde found in cigarette smoke, on arachidonic acid metabolism in cultured bovine tracheal epithelial cells. Confluent airway epithelial cell monolayers, prelabeled with (3H)arachidonic acid, released significant levels of 3H activity when exposed (20 min) to 100 microM acrolein. (3H)arachidonic acid products were resolved using reverse-phase high-performance liquid chromatography. Under control conditions the released 3H activity coeluted predominantly with the cyclooxygenase product, prostaglandin (PG) E2. After exposure to acrolein, significant peaks in 3H activity coeluted with the lipoxygenase products 12-hydroxyeicosatetraenoic acid (HETE) and 15-HETE, as well as with PGE2, PGF2 alpha, and 6-keto-PGF1 alpha. Dose-response relationships for acrolein-induced release of immunoreactive PGF2 alpha and PGE2 from unlabeled epithelial monolayers demonstrated 30 microM acrolein as the threshold dose, with 100 microM acrolein inducing nearly a fivefold increase in both PGF2 alpha and PGE2. Cellular viability after exposure to 100 microM acrolein, determined by released lactate dehydrogenase activity, was not affected until exposure periods were greater than or equal to 2 h. These results implicate the airway epithelial cell as a possible source of eicosanoids after exposure to acrolein.

  17. Cells

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    Zhao-Hui Jin

    2012-11-01

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

  18. Surfactant-induced alteration of arachidonic acid metabolism of mammalian cells in culture.

    Science.gov (United States)

    De Leo, V A; Harber, L C; Kong, B M; De Salva, S J

    1987-04-01

    Primary irritancy in human and animal skin is characterized by an inflammatory reaction mediated, in part, by membrane-derived arachidonate metabolites. One of the mechanisms of this reaction was investigated in cultured mammalian cells using three surfactants: linear alkyl benzene sulfonate (LAS), alkyl ethoxylate sulfate (AEOS), and TWEEN 20. These compounds listed in order in vivo irritancy are LAS greater than AEOS greater than TWEEN 20. Each of these compounds was studied in C3H-10T1/2 cells and human keratinocytes which had been prelabeled with 3H-labeled arachidonic acid (AA). After labeling, media were removed, cells were washed, and fresh media with or without surfactant were added. Cells were then incubated for 2 hr, media were removed and centrifuged, and an aliquot was assayed by liquid scintillation for release of label. In C3H-10T1/2 cells LAS and AEOS in 5-50 microM concentration stimulated 2 to 10 times the release of [3H]AA as compared to controls. In contrast, concentrations of 50-100 microM of TWEEN were required to release [3H]AA. With keratinocytes the same rank order of surfactant concentrations necessary for release was obtained as found with C3H-10T1/2 cells. High-performance liquid chromatography of media extracts of both cell systems revealed surfactant stimulation of the production of cyclooxygenase AA metabolites. These results confirm the induction of release by primary irritants of fatty acid groups from membrane phospholipids. Subsequent metabolism of these fatty acid groups are an integral part of the primary irritant response. Data presented with three known irritants in this in vitro model show a direct correlation with in vivo studies.

  19. Re-evaluation of thin layer chromatography as an alternative method for the quantification of prostaglandins from rat Kupffer cells.

    Science.gov (United States)

    Pestel, Sabine; Jungermann, Kurt; Schieferdecker, Henrike L

    2005-01-01

    In contrast to conventionally used immunoassays, thin layer chromatography (TLC)--by prelabeling of cells with radioactive arachidonic acid (AA)--allows to differentiate between cellularly built and added prostanoids and thus to investigate feedback effects of prostanoids on their own release. PGD2, TXB2 and PGE2 released from zymosan-stimulated Kupffer cells were separated with distinct RF-values, corresponding to those of the pure substances. Quantification of PGD2 and PGE2 gave comparable results with TLC and immunoassays, but measurement in the presence of added prostanoids was only possible with TLC. Moreover TLC was superior to immunoassays in having a longer linear range while being comparably sensitive. Cellularly built TXB2 in its radioactively labeled form was not detectable by TLC. Inhibition of TXB2 release by externally added AA or technical artifacts were excluded, suggesting that the cellular AA-pools used for prostaglandin and thromboxane synthesis differ in their accessibility for added AA. Thus, TLC is a simple, sensitive and precise method for the quantification of cellularly built prostaglandins but not of thromboxane even in the presence of added prostanoids.

  20. Similarity of Bovine Rotavirus Receptor and Human Rotavirus Receptor

    Institute of Scientific and Technical Information of China (English)

    苏琦华; 訾自强; 潘菊芬; 徐燕

    2004-01-01

    The monoclonal antibody against bovine rotavirus (BRV) receptor (BRV-R-mAb) was used to explore the similarity between the receptors of BRV and human rotavirus (HRV). ELISA, dot immunobinding assay, cell protection assay, solid-phase assay and immunohistochemistry method were applied. BRV-R-mAb bound both anti-BRV IgG and anti-HRV IgG respectively and could protect MA 104 cells against BRV and HRV challenges. Immunohistochemistry test showed that there were rotavirus receptors on the surfaces of foetal intestinal, tracheal mucosa and MA 104 cells membrane. We purified the rotavirus receptors on MA 104 ceils, which could bind both BRV and HRV in vitro. It is concluded that BRV receptor and HRV receptor are homogenous proteins and can be recognized by both BRV and HRV.

  1. The loss of plasma membrane lysopip and an increase of PIP sub 2 result from treatment of carrot cells with fungal enzymes

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Q.; Boss, W.F. (North Carolina State Univ., Raleigh (USA))

    1989-04-01

    The plasma membranes of carrot cells grown in suspension culture are enriched with PIP, lysoPIP, and PIP{sub 2}. To determine whether or not these lipids are involved in signal transduction, we have challenged the cells with a mixture of fungal cellulases, Driselase, and monitored the changes in the phosphoinositides and in the phosphoinositide kinase activity. With cell prelabeled with ({sup 3}H)inositol, two major changes are observed: (1) lysoPIP decreases 30% compared to the sorbitol control and (2) PIP{sub 2} doubles. There is no increase in IP, IP{sub 2}, or IP{sub 3}. In vitro phosphorylation studies using ({gamma}-{sup 32}P)ATP indicate that the increase in PIP{sub 2} is due in part to activation of the PIP kinase. These data suggest that the role of the polyphosphoinositides in signal transduction in plants may involve activation of the PIP kinase and/or activation of A type phospholipases rather than C type phospholipases.

  2. Cell killing by simian virus 40: impairment of membrane formation and function.

    Science.gov (United States)

    Norkin, L C

    1977-03-01

    Simian virus 40 infection of the CV-1 line of green monkey kidney cells results in the release of mitochondrial malic dehydrogenase as early as 24 h. Released malic dehydrogenase is detected in the cytoplasm prior to its appearance in the overlay medium. Infected cells lose the ability to consume oxygen between 48 and 56 h, and damage to the elctron transport system is indicated. Nevertheless, cellular ATP levels remain high as late as 72 h. Infection leads to a stimulation of membrane phospholipid synthesis, which reaches a peak at about 32 h. This is followed by a severe decline in new membrane synthesis, which correlates in time with the release of cytoplasmic lactic dehydrogenase into the overlay media. Lactic dehydrogenase release precedes the accumulation of trypan blue-stainable cells by about 6 h. Infection had no effect on the turnover of prelabeled membrane phospholipids. An early simian virus 40 mutant, tsA58, and a late mutant, tsB11, are both less effective than wild-type virus at causing reduced levels of phospholipid synthesis, enzyme release, and the accumulation of trypan blue-stainable cells. Another late mutant, tsB8, is similar to wild-type virus in these respects. At 64 h, there is no detectable cell-associated lactic dehydrogenase and nearly all the cells are trypan blue stainable. Nevertheless, at concentrations of deoxyglucose in the medium below the transport Km, deoxyglucose uptake was similar in infected and control cultures. With higher concentrations of deoxyglucose in the medium, uptake by the infected cultures exceeded that by the control cultures.

  3. Phosphoinositides metabolism in primary culture of dog thyroid cells: Effects of thyrotropin and carbachol

    Energy Technology Data Exchange (ETDEWEB)

    Taguchi, M.; Field, J.B. (St Luke' s Episcopal Hospital, Houston, TX (USA))

    1990-04-01

    Thyrotropin (TSH) and carbachol stimulated in a dose-dependent manner the accumulation of 3H-glycerophosphoinositol (GPI), 3H-inositol monophosphate (IP1), 3H-inositol bisphosphate (IP2) and 3H-inositol trisphosphate (IP3) in primary cultures of dog thyroid cells prelabeled with myo-(2-3H)inositol. TSH, 250 mU/mL, stimulated 3H-IP3 level after a 10-minute incubation while 10 mU/mL TSH increased it during a 60-minute incubation. The effect of carbachol was more rapid and greater than that of TSH. Carbachol, 100 mumol/L, elevated 3H-IP3 after a 2-minute incubation and 3H-IP3 formation was increased by as little as 1 mumol/L carbachol. TSH stimulation was observed only if the cells were deprived of TSH for 5 days before being labeled with 3H-inositol. Prolongation of the labeling period or addition of TSH, (Bu)2cAMP or carbachol during the labeling increased 3H-inositol incorporation into polyphoinositides (PIPs). When the cells were labeled without any other addition, control and TSH-stimulated 3H-IP3 levels increased in parallel with 3H-PIP levels. However, TSH or carbachol-stimulated 3H-IP3 levels did not increase in proportion to 3H-PIPs level when the cells were labeled with TSH or (Bu)2cAMP. Thus, the ratio of 3H-IP3/3H-PIPs (both control and TSH or carbachol-stimulated) decreased in the cells labeled with TSH or (Bu)2cAMP, which might reflect TSH stimulation of 3H-inositol incorporation into PIPs pool(s) that do not participate in hormone-induced hydrolysis of PIPs.

  4. Properties and fate of oligodendrocyte progenitor cells in the corpus callosum, motor cortex, and piriform cortex of the mouse.

    Science.gov (United States)

    Clarke, Laura E; Young, Kaylene M; Hamilton, Nicola B; Li, Huiliang; Richardson, William D; Attwell, David

    2012-06-13

    Oligodendrocyte progenitor cells (OPCs) in the postnatal mouse corpus callosum (CC) and motor cortex (Ctx) reportedly generate only oligodendrocytes (OLs), whereas those in the piriform cortex may also generate neurons. OPCs have also been subdivided based on their expression of voltage-gated ion channels, ability to respond to neuronal activity, and proliferative state. To determine whether OPCs in the piriform cortex have inherently different physiological properties from those in the CC and Ctx, we studied acute brain slices from postnatal transgenic mice in which GFP expression identifies OL lineage cells. We whole-cell patch clamped GFP-expressing (GFP(+)) cells within the CC, Ctx, and anterior piriform cortex (aPC) and used prelabeling with 5-ethynyl-2'-deoxyuridine (EdU) to assess cell proliferation. After recording, slices were immunolabeled and OPCs were defined by strong expression of NG2. NG2(+) OPCs in the white and gray matter proliferated and coexpressed PDGFRα and voltage-gated Na(+) channels (I(Na)). Approximately 70% of OPCs were capable of generating regenerative depolarizations. In addition to OLIG2(+) NG2(+) I(Na)(+) OPCs and OLIG2(+) NG2(neg) I(Na)(neg) OLs, we identified cells with low levels of NG2 limited to the soma or the base of some processes. These cells had a significantly reduced I(Na) and a reduced ability to incorporate EdU when compared with OPCs and probably correspond to early differentiating OLs. By combining EdU labeling and lineage tracing using Pdgfrα-CreER(T2) : R26R-YFP transgenic mice, we double labeled OPCs and traced their fate in the postnatal brain. These OPCs generated OLs but did not generate neurons in the aPC or elsewhere at any time that we examined.

  5. Action of luteinizing hormone-releasing hormone in rat ovarian cells: Hormone production and signal transduction

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Jian.

    1989-01-01

    The present study was conducted to investigate the hypothesis that the breakdown of membrane phosphoinositides may participate in the actions of luteinizing hormone-releasing hormone (LHRH) on hormone production in rat granulosa cells. In cells prelabeled with ({sup 3}H)inositol or ({sup 3}H)arachidonic acid (AA), treatment with LHRH increased the formation of radiolabeled inositol 1,4,5-trisphosphate (IP{sub 3}) and diacylglycerol (DG), and the release of radiolabeled AA. Since IP{sub 3} induces intracellular Ca{sup 2+} mobilization, changes in the cytosolic free calcium ion concentrations ((Ca{sup 2+})i) induced by LHRH were studied in individual cells using fura-2 microspectrofluorimetry. Alterations in (Ca{sup 2+})i induced by LHRH were rapid and transient, and could be completely blocked by a LHRH antagonist. Sustained perifusion of LHRH resulted in a desensitization of the (Ca{sup 2+})i response to LHRH. LHRH treatment accelerated (Ca{sup 2+})i depletion in the cells perifused with Ca{sup 2+} free medium, indicating the involvement of intracellular Ca{sup 2+} pool(s) in (Ca{sup 2+})i changes. The actions of LHRH on the regulation of progesterone (P{sub 4}) and prostaglandin E{sub 2} (PGE{sub 2}) production were also examined. LHRH increased basal P{sub 4} production and attenuated FSH induced P{sub 4} production. Both basal and FSH stimulated PGE{sub 2} formation were increased by LHRH. Since LHRH also increased the formation of DG that stimulates the activity of protein kinase C, an activator of protein kinase C (12-0-tetradecanolyphorbol-13-acetate: TPA) was used with the Ca{sup 2+} ionophore A23187 and melittin (an activator of phospholipase A{sub 2}) to examine the roles of protein kinase C, Ca{sup 2+} and free AA, respectively, in LHRH action.

  6. Generation of lipid neutrophil chemoattractant by irradiated bovine aortic endothelial cells.

    Science.gov (United States)

    Matzner, Y; Cohn, M; Hyam, E; Razin, E; Fuks, Z; Buchanan, M R; Haas, T A; Vlodavsky, I; Eldor, A

    1988-04-15

    Radiation injury to blood vessels is associated with an acute inflammatory process. We investigated the capacity of cultured bovine aortic endothelial cells (BAEC) to produce chemotactic factors after radiation injury. BAEC in serum-free media were irradiated with a cobalt-60 Gammacell 220 and the cell supernatants were assayed for chemotactic activity for human neutrophils in a Boyden chamber. There was a rapid release of chemotactic activity into the BAEC supernatants which was dependent both on the dose of radiation (5 to 40 Gy) and the time between irradiation and sample collection. In contrast, isolation of BAEC lysates by freeze-thawing was not associated with the presence of similar chemotactic activity. The chemotactic activity released from the irradiated BAEC was not destroyed by boiling nor by treatment with trypsin. The release of the chemotactic activity was, however, inhibited by the addition of a lipoxygenase inhibitor but not by the addition of a cyclooxygenase inhibitor before the irradiation. The chemotactic activity was recovered from the cell supernatants in the lipid phase after extraction with chloroform/methanol. Furthermore, the chloroform/methanol extracts co-eluted with authentic leukotriene B4 when the BAEC were prelabeled with [14C] arachidonic acid. However, we were unable to detect endogenous leukotriene B4 with RIA. Instead, the only detectable endogenous lipid present in the supernatants was 13-hydroxyoctadecadienoic acid which is derived from linoleic acid via the lipoxygenase pathway. 13-Hydroxyoctadecadienoic acid, however, had no chemotactic activity. These findings suggest that endothelial cells rapidly release a chemotactic agent after irradiation, the release of which is associated with a lipoxygenase pathway. The release of this chemotactic activity may account in part for the acute inflammatory response that is observed after ionizing irradiation.

  7. Variability in contrast agent uptake by different but similar stem cell types

    Directory of Open Access Journals (Sweden)

    Ketkar-Atre A

    2013-11-01

    Full Text Available Ashwini Ketkar-Atre,1 Tom Struys,1,2 Stefaan J Soenen,3 Ivo Lambrichts,2 Catherine M Verfaillie,4 Marcel De Cuyper,5 Uwe Himmelreich1 1Biomedical MRI/MoSAIC, Department of Imaging and Pathology, Biomedical Sciences Group, Katholieke Universiteit Leuven, Leuven, Belgium; 2Lab of Histology, Biomedical Research Institute, Hasselt University, Campus Diepenbeek, Agoralaan, Diepenbeek, Belgium; 3Lab for General Biochemistry and Physical Pharmacy, Faculty of Pharmacy, Ghent University, Ghent, Belgium; 4Interdepartmental Stem Cell Institute, O&N IV, Katholieke Universiteit Leuven, Leuven, Belgium; 5Laboratory of BioNanoColloids, Interdisciplinary Research Centre, Katholieke Universiteit Leuven, Kortrijk, Belgium Abstract: The need to track and evaluate the fate of transplanted cells is an important issue in regenerative medicine. In order to accomplish this, pre-labelling cells with magnetic resonance imaging (MRI contrast agents is a well-established method. Uptake of MRI contrast agents by non-phagocytic stem cells, and factors such as cell homeostasis or the adverse effects of contrast agents on cell biology have been extensively studied, but in the context of nanoparticle (NP-specific parameters. Here, we have studied three different types of NPs (Endorem®, magnetoliposomes [MLs], and citrate coated C-200 to label relatively larger, mesenchymal stem cells (MSCs and, much smaller yet faster proliferating, multipotent adult progenitor cells (MAPCs. Both cell types are similar, as they are isolated from bone marrow and have substantial regenerative potential, which make them interesting candidates for comparative experiments. Using NPs with different surface coatings and sizes, we found that differences in the proliferative and morphological characteristics of the cells used in the study are mainly responsible for the fate of endocytosed iron, intracellular iron concentration, and cytotoxic responses. The quantitative analysis, using high

  8. Pig membrana granulosa cells prevent resumption of meiosis in cattle oocytes.

    Science.gov (United States)

    Kalous, J; Sutovsky, P; Rimkevicova, Z; Shioya, Y; Lie, B L; Motlik, J

    1993-01-01

    Membrana granulosa was isolated from healthy large antral follicles of prepubertal or cyclic gilts stimulated with PMSG or PMSG and hCG. Ultrastructural observations revealed that pieces of pig membrana granulosa were associated with the basement membrane. The cattle cumulus-enclosed oocytes (COC) were placed in the rolled pieces of the pig membrana granulosa (PMG). After 8 and 24 hr of coculture with PMG from prepubertal gilts, only 16% and 21% of oocytes underwent GVBD, respectively. PMG from PMSG-stimulated cyclic gilts blocked the resumption of meiosis in all COC. The inhibitory effect of heterologous granulosa cells was fully reversible. When COC were initially incubated for 2 and 4 hr, subsequent culture in PMG prevented GVBD in 100% and 36% of oocytes, respectively. This suggests that functional contact between COC and PMG was established during the first 2 hr of coculture. To follow metabolic cooperation between PMG and COC, PMG was prelabeled with 3H-uridine and cocultured with COC. Autoradiography on semithin sections revealed the intensive passage of 3H-uridine from PMG into the cumulus layer and an oocyte. COC placed in PMG after GVBD (8 and 12 hr of an initial incubation) did not extrude the first polar body. PMG isolated from cyclic gilts after PMSG and hCG stimulation also inhibited GVBD of COC. Since nearly all COC placed in PMG isolated 10 and 12 hr after hCG remained in the GV stage after 24 hr of coculture, the hCG stimulation did not substantially diminish the meiosis inhibiting activity of PMG.(ABSTRACT TRUNCATED AT 250 WORDS)

  9. The inhibition of mouse L-cell 45 S ribosomal RNA processing is a highly uv-resistant property of vesicular stomatitis virus

    Energy Technology Data Exchange (ETDEWEB)

    Zan, M.; Evans, P.; Lucas-Lenard, J. (Univ. of Connecticut, Storrs (USA))

    1990-07-01

    In mouse L cells infected with vesicular stomatitis virus (VSV), the synthesis of 45 S rRNA and its conversion to 28 S and 18 S rRNA are inhibited during the course of infection. Evidence is presented that the lack of accumulation of stable rRNA species results not only from the decreased transcription and processing of 45 S rRNA, but also from an increased breakdown of pre-rRNA or stable rRNA during processing. In cells prelabeled with (3H)uridine and then infected, the 28 S and 18 S rRNA species remain unaffected. Studies using uv-irradiated VSV indicate that the viral function involved in rRNA synthesis inhibition is slightly more sensitive to uv irradiation than the function involved in processing inhibition. These results suggest that the VSV functions involved in 45 S rRNA synthesis and processing inhibition may be related, or overlapping, but not identical. In cells infected by VSV mutant T1026R1, total RNA synthesis is inhibited, but the distribution of precursor and stable rRNA species remains nearly normal for up to 5 hr after infection. The function of the mutant virus involved in the inhibition of rRNA processing appears to be defective. In mengovirus-infected L cells, 45 S rRNA synthesis, but not processing, is severely inhibited soon after infection, indicating that a decrease in rRNA transcription is not necessarily accompanied by a decrease in processing.

  10. The Ang II-induced growth of vascular smooth muscle cells involves a phospholipase D-mediated signaling mechanism.

    Science.gov (United States)

    Freeman, E J

    2000-02-15

    Angiotensin (Ang) II acts as a mitogen in vascular smooth muscle cells (VSMC) via the activation of multiple signaling cascades, including phospholipase C, tyrosine kinase, and mitogen-activated protein kinase pathways. However, increasing evidence supports signal-activated phospholipases A(2) and D (PLD) as additional mechanisms. Stimulation of PLD results in phosphatidic acid (PA) formation, and PA has been linked to cell growth. However, the direct involvement of PA or its metabolite diacylglycerol (DAG) in Ang II-induced growth is unclear. PLD activity was measured in cultured rat VSMC prelabeled with [(3)H]oleic acid, while the incorporation of [(3)H]thymidine was used to monitor growth. We have previously reported the Ang II-dependent, AT(1)-coupled stimulation of PLD and growth in VSMC. Here, we show that Ang II (100 nM) and exogenous PLD (0.1-100 units/mL; Streptomyces chromofuscus) stimulated thymidine incorporation (43-208% above control). PA (100 nM-1 microM) also increased thymidine incorporation to 135% of control. Propranolol (100 nM-10 microM), which inhibits PA phosphohydrolase, blocked the growth stimulated by Ang II, PLD, or PA by as much as 95%, an effect not shared by other beta-adrenergic antagonists. Propranolol also increased the production of PA in the presence of Ang II by 320% and reduced DAG and arachidonic acid (AA) accumulation. The DAG lipase inhibitor RHC-80267 (1-10 microM) increased Ang II-induced DAG production, while attenuating thymidine incorporation and release of AA. Thus, it appears that activation of PLD, formation of PA, conversion of PA to DAG, and metabolism of DAG comprise an important signaling cascade in Ang II-induced growth of VSMC.

  11. Interferencia de la infección por rotavirus mediante la inhibición de la actividad de la proteína disulfuro isomerasa (DPI de la membrana celular de las líneas MA104 y Caco-2.

    Directory of Open Access Journals (Sweden)

    Carlos Arturo Guerrero Fonseca

    2008-12-01

    Full Text Available

    Los rotavirus son la causa más común de gastroenteritis severa en niños menores de cinco años, ocasionando episodios diarreicos agudos responsables de 454.000 a 705.000 muertes anuales a nivel mundial.
     
    Aunque la frecuencia de infección con rotavirus es muy similar a través del mundo, en los países en desarrollo la gastroenteritis rotaviral es la mayor causa de muerte infantil. 
     
    La diarrea rotaviral severa cursa con vómito y fiebre, produciendo deshidratación con shock, desbalance electrolítico, y muerte si esta no es tratada. En los países desarrollados, la infección rotaviral es responsable del 30 - 50% de las hospitalizaciones debidas a gastroenteritis en menores de 5 años. 
    Además, los rotavirus son una causa importante en la gastroenteritis nosocomial.
     
     
     

  12. The effect of adipose tissue-derived stem cells in a middle cerebral artery occlusion stroke model depends on their engraftment rate.

    Science.gov (United States)

    Grudzenski, Saskia; Baier, Sebastian; Ebert, Anne; Pullens, Pim; Lemke, Andreas; Bieback, Karen; Dijkhuizen, Rick M; Schad, Lothar R; Alonso, Angelika; Hennerici, Michael G; Fatar, Marc

    2017-04-26

    In the field of experimental stem cell therapy, intra-arterial (IA) delivery yields the best results concerning, for example, migrated cell number at the targeted site. However, IA application also appears to be associated with increased mortality rates and infarction. Since many rodent studies systemically apply 1 × 10(6) cells, this could also be a consequence of engrafted cell number. The aim of this study was therefore to investigate the effect of different doses of adipose tissue-derived stem cells (ASCs) on engraftment rates and stroke outcome measured in vivo using 9.4-T high-field magnetic resonance imaging (MRI). Male Wistar rats (n = 43) underwent a middle cerebral artery occlusion (MCAo) for 45 or 90 min, followed by IA delivery of either saline or 1 × 10(6), 3 × 10(5), or 5 × 10(4) ASCs pre-labelled with very small superparamagnetic iron oxide particles (VSOPs). MRI (9.4-T) analysis was performed 48 h and 9 days post-MCAo. Lesion volumes were assessed by analysis of T2-weighted images and cell signal tracking showing cell engraftment and active cell migration by an improved T2*-analysis. The ASC-derived signal intensity increased in the affected hemisphere 48 h post MCAo with injected cell number (p stroke volumes revealed an increased infarction after injection of 1 × 10(6) ASCs compared to controls or application of 5 × 10(4) ASCs (p cell numbers between both MRI examinations but showed active ASC migration to the site of infarction. Our results confirm that IA injection is an efficient way of targeting damaged brain tissue but its usefulness strongly depends on the right dose of delivered stem cells since this factor has a strong influence on migration rate and infarct volume, with better results for doses below 1 × 10(6) cells. Future challenges will include the determination of therapeutic doses for best cellular engraftment and stroke outcome.

  13. Intranasal delivery of hypoxia-preconditioned bone marrow-derived mesenchymal stem cells enhanced regenerative effects after intracerebral hemorrhagic stroke in mice.

    Science.gov (United States)

    Sun, Jinmei; Wei, Zheng Zachory; Gu, Xiaohuan; Zhang, James Ya; Zhang, Yongbo; Li, Jimei; Wei, Ling

    2015-10-01

    Intracerebral hemorrhagic stroke (ICH) causes high mortality and morbidity with very limited treatment options. Cell-based therapy has emerged as a novel approach to replace damaged brain tissues and promote regenerative processes. In this study we tested the hypothesis that intranasally delivered hypoxia-preconditioned BMSCs could reach the brain, promote tissue repair and improve functional recovery after ICH. Hemorrhagic stroke was induced in adult C57/B6 mice by injection of collagenase IV into the striatum. Animals were randomly divided into three groups: sham group, intranasal BMSC treatment group, and vehicle treatment group. BMSCs were pre-treated with hypoxic preconditioning (HP) and pre-labeled with Hoechst before transplantation. Behavior tests, including the mNSS score, rotarod test, adhesive removal test, and locomotor function evaluation were performed at varying days, up to 21days, after ICH to evaluate the therapeutic effects of BMSC transplantation. Western blots and immunohistochemistry were performed to analyze the neurotrophic effects. Intranasally delivered HP-BMSCs were identified in peri-injury regions. NeuN+/BrdU+ co-labeled cells were markedly increased around the hematoma region, and growth factors, including BDNF, GDNF, and VEGF were significantly upregulated in the ICH brain after BMSC treatment. The BMSC treatment group showed significant improvement in behavioral performance compared with the vehicle group. Our data also showed that intranasally delivered HP-BMSCs migrated to peri-injury regions and provided growth factors to increase neurogenesis after ICH. We conclude that intranasal administration of BMSC is an effective treatment for ICH, and that it enhanced neuroregenerative effects and promoted neurological functional recovery after ICH. Overall, the investigation supports the potential therapeutic strategy for BMSC transplantation therapy against hemorrhagic stroke. Copyright © 2015 Elsevier Inc. All rights reserved.

  14. Thyroxine signal transduction in liver cells involves phospholipase C and phospholipase D activation. Genomic independent action of thyroid hormone

    Directory of Open Access Journals (Sweden)

    Krasilnikova Oksana A

    2001-04-01

    Full Text Available Abstract Background Numerous investigations demonstrate a novel role of thyroid hormone as a modulator of signal transduction. Protein kinase C (PKC is critical to the mechanism by which thyroid hormones potentiate both the antiviral and immunomodulatory actions of IFNγ in different cells and regulate the exchange of signalling phospholipids in hepatocytes. Because nothing is known about accumulation of PKC modulator - diacylglycerol in cells treated with T4, we examined the nongenomic effect of thyroid hormones on DAG formation and phospholipase activation in liver cells. Results The results obtained provide the first demonstration of phospholipase C, phospholipase D and protein kinase C nongenomic activation and diacylglycerol (DAG accumulation by L-T4 in liver cells. The experiments were performed in either the [14C]CH3COOH-labeled rat liver slices or isolated hepatocytes pre-labeled by [14C]oleic acid. L-T4 activates the DAG production in a concentration- and time-dependent manner. DAG formation in stimulated cells is biphasic and short-lived event: there is an initial, rapid rise in DAG concentration and then a slower accumulation that can be sustained for a few minutes. The early phase of L-T4 generated DAG only is accompanied by phosphatidylinositol 4,5-bisphosphate level decrease and inositol 1,4,5-trisphosphate formation while the second phase is abolished by PKC inhibitor l,(5-isoquinolinesulphonyl2methylpiperasine dihydrochloride (H7 and propranolol. The second phase of DAG production is accompanied by free choline release, phosphatidylcholine content drop and phosphatidylethanol (Peth formation. Inhibitor of phospholipase-C-dependent phosphoinositide hydrolysis, neomycin sulfate, reduced the Peth as well as the DAG response to L-T4. Conclusions The present data have indicated the DAG signaling in thyroid hormone-stimulated liver cells. L-thyroxine activates a dual phospholipase pathway in a sequential and synchronized manner

  15. Inhibition by prostaglandin E(2) of anaphylatoxin C5a- but not zymosan-induced prostanoid release from rat Kupffer cells.

    Science.gov (United States)

    Pestel, Sabine; Jungermann, Kurt; Götze, Otto; Schieferdecker, Henrike L

    2002-04-01

    The proinflammatory anaphylatoxin C5a induces the release of prostanoids, ie, prostaglandins (PG) and thromboxane (TX), from the resident liver macrophages (Kupffer cells [KC]). Because KC themselves express prostanoid receptors, prostanoids--besides having paracrine functions--might regulate their own release in an autocrine loop. So far, such a possible feedback regulation has not been investigated systematically, probably because of methodological difficulties to measure newly synthesized prostanoids in the presence of added prostanoids. Here, after prelabeling of phospholipids with [(14)C]arachidonate, cellularly formed [(14)C]prostanoids were determined in the presence of added unlabelled prostanoids by thin layer chromatography. In cultured KC, recombinant rat C5a (rrC5a) rapidly increased PGD(2), PGE(2), and TXA(2) release, which was strongly reduced by PGE(2), but neither by PGD(2) nor by the TXA(2) analog U46619. The inhibitory effect of PGE(2) was mimicked by cAMP, indicating that the G(s)-coupled PGE(2) receptors type 2 or 4 were involved. Zymosan also enhanced prostanoid release from KC, but with slightly slower kinetics; this action was neither inhibited by PGE(2) nor by cAMP. Also in perfused rat livers, rrC5a enhanced prostanoid release from KC as shown by prostanoid overflow and thereby indirectly increased glucose output from hepatocytes. Again, PGE(2), but not PGD(2), inhibited rrC5a-elicited prostanoid overflow. This resulted in a complete inhibition of rrC5a-induced, prostanoid-mediated glucose output. Thus, PGE(2) can inhibit specifically the C5a-induced prostanoid release from KC via a feedback mechanism and thereby limit prostanoid-mediated hepatocellular defense reactions, eg, glucose release.

  16. The CORM ALF-186 Mediates Anti-Apoptotic Signaling via an Activation of the p38 MAPK after Ischemia and Reperfusion Injury in Retinal Ganglion Cells

    Science.gov (United States)

    Ulbrich, Felix; Kaufmann, Kai B.; Meske, Alexander; Lagrèze, Wolf A.; Augustynik, Michael; Buerkle, Hartmut; Ramao, Carlos C.; Biermann, Julia

    2016-01-01

    Purpose Ischemia and reperfusion injury may induce apoptosis and lead to sustained tissue damage and loss of function, especially in neuronal organs. While carbon monoxide is known to exert protective effects after various harmful events, the mechanism of carbon monoxide releasing molecules in neuronal tissue has not been investigated yet. We hypothesize that the carbon monoxide releasing molecule (CORM) ALF-186, administered after neuronal ischemia-reperfusion injury (IRI), counteracts retinal apoptosis and its involved signaling pathways and consecutively reduces neuronal tissue damage. Methods IRI was performed in rat´s retinae for 1 hour. The water-soluble CORM ALF-186 (10 mg/kg) was administered intravenously via a tail vein after reperfusion. After 24 and 48 hours, retinal tissue was harvested to analyze mRNA and protein expression of Bcl-2, Bax, Caspase-3, ERK1/2, p38 and JNK. Densities of fluorogold pre-labeled retinal ganglion cells (RGC) were analyzed 7 days after IRI. Immunohistochemistry was performed on retinal cross sections. Results ALF-186 significantly reduced IRI mediated loss of RGC. ALF-186 treatment differentially affected mitogen-activated protein kinases (MAPK) phosphorylation: ALF-186 activated p38 and suppressed ERK1/2 phosphorylation, while JNK remained unchanged. Furthermore, ALF-186 treatment affected mitochondrial apoptosis, decreasing pro-apoptotic Bax and Caspase-3-cleavage, but increasing anti-apoptotic Bcl-2. Inhibition of p38-MAPK using SB203580 reduced ALF-186 mediated anti-apoptotic effects. Conclusion In this study, ALF-186 mediated substantial neuroprotection, affecting intracellular apoptotic signaling, mainly via MAPK p38. CORMs may thus represent a promising therapeutic alternative treating neuronal IRI. PMID:27764224

  17. Rotavirus-Like Particles: A Novel Nanocarrier for the Gut

    Directory of Open Access Journals (Sweden)

    Naima G. Cortes-Perez

    2010-01-01

    Full Text Available The delivery of bioactive molecules directly to damaged tissues represents a technological challenge. We propose here a new system based on virus-like particles (VLP from rotavirus, with a marked tropism for the gut to deliver bio-active molecules to intestinal cells. For this, nonreplicative VLP nanoparticles were constructed using a baculovirus expression system and used to deliver an exogenous biomolecule, the green fluorescent protein (GFP, into either MA104 cells or intestinal cells from healthy and 2,4,6-trinitrobenzene sulfonic acid (TNBS-treated mice. Our results show that expression of rotavirus capsid proteins in baculovirus led to the auto assembly of VLP that display similar properties to rotavirus. In vitro experiments showed that VLP were able to enter into MA104 cells and deliver the reporter protein. Intragastric administration of fluorescent VLP in healthy and TNBS-treated mice resulted in the detection of GFP and viral proteins in intestinal samples. Our results demonstrate an efficient entry of non-replicative rotavirus VLP into the epithelial cell line MA104 and provide the first in vivo evidence of the potential of these nanoparticles as a promising safe candidate for drug delivery to intestinal cells.

  18. In Vitro Antiviral Activity of Rubia Cordifolia Aerial Part Extract Against Rotavirus

    Directory of Open Access Journals (Sweden)

    Yuanyuan Sun

    2016-09-01

    Full Text Available The root of Rubia cordifolia (R. cordifolia has been used traditionally as a hemostatic agent, while the aerial part of the plant consisting of leaf and stem is known to exhibit anti-diarrheal properties and has been widely used as a remedy in many parts of China. As rotavirus is one of the most commonly associated diarrhea-causing pathogen, this study aims to investigate the anti-rotaviral effect of R. cordifolia aerial part (RCAP. The cytotoxicity of RCAP towards MA-104 cells was evaluated using the WST-8 assay. Colloidal gold method and real time polymerase chain reaction (qPCR assay were used to confirm the findings of the antiviral assay. Then, 4',6-diamidino-2-phenylindole (DAPI staining method was subsequently used to investigate the mode of death among the cells. And the representative components of aqueous extract were isolated and identified. It was shown that both the viability of MA-104 cells and the viral load were reduced with increasing concentration of the extract. DAPI staining showed that virus-induced apoptosis was the cause of the low cell viability and viral load, an effect which was accelerated with incubation in the aqueous herbal extract. The major compounds postulated to exhibit this activity were isolated from the aqueous herbal extract and identified to be compounds Xanthopurpurin and Vanillic Acid. This study showed that RCAP extract effectively inhibited rotavirus multiplication by promoting virus-induced apoptosis in MA-104 cells.

  19. Mechanistic studies of semicarbazone triapine targeting human ribonucleotide reductase in vitro and in mammalian cells: tyrosyl radical quenching not involving reactive oxygen species.

    Science.gov (United States)

    Aye, Yimon; Long, Marcus J C; Stubbe, JoAnne

    2012-10-12

    Triapine® (3-aminopyridine-2-carboxaldehyde thiosemicarbazone (3-AP)) is a drug in Phase II trials. One of its established cellular targets is the β(2) subunit of ribonucleotide reductase that requires a diferric-tyrosyl-radical [(Fe(III)(2)-Y·)(Fe(III)(2))] cofactor for de novo DNA biosynthesis. Several mechanisms for 3-AP inhibition of β(2) have been proposed; one involves direct iron chelation from β(2), whereas a second involves Y· destruction by reactive oxygen species formed in situ in the presence of O(2) and reductant by Fe(II)-(3-AP). Inactivation of β(2) can thus arise from cofactor destruction by loss of iron or Y·. In vitro kinetic data on the rates of (55)Fe and Y· loss from [((55)Fe(III)(2)-Y·)((55)Fe(III)(2))]-β(2) under aerobic and anaerobic conditions reveal that Y· loss alone is sufficient for rapid β(2) inactivation. Oxyblot(TM) and mass spectrometric analyses of trypsin-digested inhibited β(2), and lack of Y· loss from H(2)O(2) and O(2)(•) treatment together preclude reactive oxygen species involvement in Y· loss. Three mammalian cell lines treated with 5 μm 3-AP reveal Y· loss and β(2) inactivation within 30-min of 3-AP-exposure, analyzed by whole-cell EPR and lysate assays, respectively. Selective degradation of apo- over [(Fe(III)(2)-Y·)(Fe(III)(2))]-β(2) in lysates, similar iron-content in β(2) immunoprecipitated from 3-AP-treated and untreated [(55)Fe]-prelabeled cells, and prolonged (12 h) stability of the inhibited β(2) are most consistent with Y· loss being the predominant mode of inhibition, with β(2) remaining iron-loaded and stable. A model consistent with in vitro and cell-based biochemical studies is presented in which Fe(II)-(3-AP), which can be cycled with reductant, directly reduces Y· of the [(Fe(III)(2)-Y·)(Fe(III)(2))] cofactor of β(2).

  20. Stem Cells

    Science.gov (United States)

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

  1. Cells, cells, and more cells.

    Science.gov (United States)

    Bhatti, M Tariq; Gres, Katherine E; Petitto, Virginia B; Cross, Shelley Ann

    2007-01-01

    A 64-year-old woman presented with bilateral optic nerve swelling, vitreous cells, and cerebrospinal fluid monocytic pleocytosis. A chest radiograph and computed tomography demonstrated a lesion in the left lung, which histologically was confirmed to be a small-cell lung carcinoma. The serum was positive for the anti-CV2 (anti-CRMP-5) antibody. Following treatment with chemoradiation the optic nerve swelling and vitritis resolved. The differential diagnosis of uveal-meningeal diseases is discussed and the pathophysiology and clinical manifestations of paraneoplastic syndromes reviewed.

  2. Study on the combination of PKH26 and DAPI to trace bone marrow stem cells homing in mice model of cerebral ischemia%PKH26和DAPI联合示踪骨髓干细胞在脑缺血模型小鼠脑内迁移的实验研究

    Institute of Scientific and Technical Information of China (English)

    张雪梅; 杜芳; 杨丹; 户宏艳; 付锦

    2011-01-01

    Objective To explore the method to trace bone marrow stem cells in mice model of cerebral ischemia by using PKH26 and DAPI fluorescence dye. Methods BMMCs were harvested from BALB/c mice and then doubly labeled with PKH26 and DAPI. The labeled cells were subsequently infused into the tail veins of mice in which focal cerebral ischemia model had been induced by modified electric coagulation approach. 14 days after transplantation, the migration status of the cells was studied by fluorescence microscopy. Results Positive cells pre-labeled by PKH26 and DAPI were found in the cortex region of ischemic hemisphere. Conclusions The combined use of PKH26 and DAPI to double label bone marrow stem cells can trace the transplanted cells in mice model of ischemic brain tissues.%目的 探讨PKH26和DAPI联合标记骨髓干细胞在脑内迁移过程中的示踪作用.方法 用PKH26和DAPI联合标记从Balb/c小鼠骨髓中分离出的骨髓单个核细胞(BMMCs),用改良电凝法制备局灶性脑缺血模型后,将标记的BMMCs经尾静脉移植入脑缺血小鼠体内,对照组经尾静脉注入PBS.移植2w后取脑组织,通过激光共聚焦荧光显微镜观察BMMCs向脑内迁移的情况.结果 实验组小鼠脑组织内可发现PKH26和DAPI双标的神经样细胞.结论 PKH26和DAPI可以联合标记向脑缺血模型小鼠脑组织迁移的骨髓干细胞,为体内示踪骨髓干细胞脑内迁移提供更加准确的实验方法.

  3. NSP4基因突变的重组牛轮状病毒的拯救及其鉴定%Rescue and Identification of the Recombinant Bovine Rotavirus with Mutational NSP4 Gene

    Institute of Scientific and Technical Information of China (English)

    杨少华; 何洪彬; 杨宏军; 陈方园; 高运东; 仲跻峰

    2012-01-01

    [目的]通过反向遗传技术结合RNAi筛选和蚀斑克隆方法,拯救出毒力减弱的轮状病毒(rotavirus,RV). [方法]以野生型轮状病毒CHLY基因组RNA为模板,通过重叠PCR方法在NSP4基因93-104 nt引入5个沉默突变核苷酸,并将毒力位点区135aa、136aa和138aa对应的核苷酸进行定向突变,构建了含有突变位点的转录质粒△pT7-NSP4/89/M.将该质粒与携带RNA聚合酶基因的重组质粒pcDNA3.1/T7-RNAP共转染己接种野生型RV病毒的MA104细胞单层,继续培养24 h,获得了携带NSP4变异基因的RV病毒粒子和野生型RV病毒粒子的混合病毒.将获得的混合病毒接种MA104细胞,通过RNA干扰和蚀斑克隆方法逐步筛选纯化以获得拯救RV. [结果]成功拯救出了NSP4基因变异的RV,该病毒在MA104细胞上的病变和致乳鼠腹泻效果较野生型RV明显减弱.[结论]通过反向遗传技术结合RNAi筛选和蚀斑克隆方法成功拯救出毒力减弱的RV;NSP4毒力位点135aa、136aa和138aa的变异对RV毒力改变和腹泻严重程度有影响.%[Objective] The objective of the study is to rescue the attenuated rotavirus with mutational NSP4 gene by reverse genetic method and to purify further by RNAi technique and plaque clone method. [Method] NSP4 gene of a wild type RV strain CHLY was cloned and five silent mutation nucleotides were introduced at 93 nt-109 nt and five missense mutations at 444 nt-453 nt, which resulted in M135L, I136T, A138P amino acid mutation. A recombinant plasmid ApT7-NSP4/89/D that contains T7 promoter and T7 terminator at 5' and 3' end of the manipulated NSP4 cDNA was constructed. ApT7-NSP4/89/D plasmid and expression vector pcDNA3.1/T7-RNAP carrying RNA polymerase in vivo was co-transfected MA 104 cell layer that had been infected 24 h earlier with wild type RV as helper virus, and the transfected cell was cultured for further 24 h until harvest. The culture fluid colleted was subjected to passage on MA104 cell in the presence

  4. Dendritic Cell

    OpenAIRE

    Sevda Söker

    2005-01-01

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

  5. Galvanic Cells

    Science.gov (United States)

    Young, I. G.

    1973-01-01

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

  6. Galvanic Cells

    Science.gov (United States)

    Young, I. G.

    1973-01-01

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

  7. Cell Biochips

    Science.gov (United States)

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

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

  8. Detection of porcine rotavirus from tissue and faecal specimens

    Directory of Open Access Journals (Sweden)

    Prabha Suji

    2009-01-01

    Full Text Available Porcine small intestinal sub-mucosa is a cell-free collagen matrix that has demonstrated its ability as a scaffold material. Transplantation poses special hazards because grafted tissues and organs transmit pathogens efficiently, especially viruses. Rotavirus is thought to be confined to the intestine, causing acute diarrhoea. The purpose of this study was to evaluate the porcine intestinal tissue scaffold for Rotavirus and to study the incidence of this virus among pig herds. Only one isolate was successfully adapted to grow in cell line MA 104 from faecal samples. This isolate was further confirmed by reverse transcriptase polymerase chain reaction and sequence analysis.

  9. Engineering cell-cell signaling.

    Science.gov (United States)

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

    2013-10-01

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

  10. Stem cells in cell transplantation.

    Science.gov (United States)

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

    2006-12-01

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

  11. Engineering Cell-Cell Signaling

    Science.gov (United States)

    Milano, Daniel F.; Natividad, Robert J.; Asthagiri, Anand R.

    2014-01-01

    Juxtacrine cell-cell signaling mediated by the direct interaction of adjoining mammalian cells is arguably the mode of cell communication that is most recalcitrant to engineering. Overcoming this challenge is crucial for progress in biomedical applications, such as tissue engineering, regenerative medicine, immune system engineering and therapeutic design. Here, we describe the significant advances that have been made in developing synthetic platforms (materials and devices) and synthetic cells (cell surface engineering and synthetic gene circuits) to modulate juxtacrine cell-cell signaling. In addition, significant progress has been made in elucidating design rules and strategies to modulate juxtacrine signaling based on quantitative, engineering analysis of the mechanical and regulatory role of juxtacrine signals in the context of other cues and physical constraints in the microenvironment. These advances in engineering juxtacrine signaling lay a strong foundation for an integrative approach to utilizing synthetic cells, advanced ‘chassis’ and predictive modeling to engineer the form and function of living tissues. PMID:23856592

  12. Cell Motility

    CERN Document Server

    Lenz, Peter

    2008-01-01

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

  13. Photovoltaic Cells

    Directory of Open Access Journals (Sweden)

    Karolis Kiela

    2012-04-01

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

  14. 痘苗病毒/T7RNA聚合酶辅助的原核基因在真核细胞中的表达%Expression of Prokaryotic Gene in Mammalian Cells Based on Recombinant Vaccinia Virus Encoding T7 RNA Polymerase

    Institute of Scientific and Technical Information of China (English)

    潘小霞; 张顺; 文喻玲; 袁静; 陈元鼎

    2011-01-01

    痘苗病毒/T7RNA聚合酶这一瞬时表达系统由于具有很多优于其他表达系统的特点而被广泛地应用于表达外源蛋白.TB-Chen株轮状病毒的VP6 DNA编码片段插入到原核质粒pETL的噬菌体T7启动子和终止子之间,获得重组表达质粒pET-VP6.构建好的重组表达质粒pET-VP6通过脂质体转染到真核细胞MA104中,用携带噬菌体T7RNA聚合酶基因的重组痘苗病毒vTF7-3再感染,可在细胞检测到目的蛋白VP6的表达.研究结果还显示,痘苗病毒vTF7-3感染后,细胞病变较快,严重影响了蛋白的表达量.结果提示,如果能降低痘苗病毒vTF7-3的致细胞病变作用而不影响其在细胞中合成T7 RNA聚合酶的能力,蛋白可能会得到高效表达.为进一步研究VP6基因的特性及更好地应用痘苗病毒/T7 RNA聚合酶这一瞬时表达系统提供理论基础.%The vaccinia virus/T7 RNA polymerase transient expression system relying on the bacteriophageT7 RNA polymerase with several key advantages was widely used for protein expression. VP6-encoding cDNA ofrotavirus strain TB-Chen was cloned and constructed by inserting into prokaryotic expression plasmid pETL betweenbacteriophage T7 promoter and terminator regions. When eukaryotic cells were transfeeted with the recombinantplasmid containing the VP6 gene and infected with recombinant vaccinia virus vTF7-3 which provides bacteriophageT7 RNA polymerase, the VP6 gene was expressed. The findings showed that cytopathic effects by vaccinia virusinfection were fast and severe leading to low level of protein expression. If cytopathic effects of the vaccinia viruscan be reduced, higher level of the protein might be obtained. The findings provided a helpful means to furtherstudy the VP6 function and utilize the vaccinia virus/T7 RNA polymerase transient expression system.

  15. Identification of the two rotavirus genes determining neutralization specificities

    Energy Technology Data Exchange (ETDEWEB)

    Offit, P.A.; Blavat, G.

    1986-01-01

    Bovine rotavirus NCDV and simian rotavirus SA-11 represent two distinct rotavirus serotypes. A genetic approach was used to determine which viral gene segments segregated with serotype-specific viral neutralization. There were 16 reassortant rotarviruses derived by coinfection of MA-104 cells in vitro with the SA-11 and NCDV strains. The parental origin of reassortant rotavirus double-stranded RNA segments was determined by gene segment mobility in polyacrylamide gels and by hybridization with radioactively labeled parental viral transcripts. The authors found that two rotavirus gene segments found previously to code for outer capsid proteins vp3 and vp7 cosegreated with virus neutralization specificities.

  16. Engineering Cell-Cell Signaling

    OpenAIRE

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

    2013-01-01

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

  17. Stem Cells

    Directory of Open Access Journals (Sweden)

    Madhukar Thakur

    2015-02-01

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

  18. Types of Stem Cells

    Science.gov (United States)

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

  19. Fuel Cells

    DEFF Research Database (Denmark)

    Smith, Anders; Pedersen, Allan Schrøder

    2014-01-01

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

  20. Fuel Cells

    Science.gov (United States)

    Hawkins, M. D.

    1973-01-01

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

  1. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    '. This paper is about tech-noscience, and about the proliferation of connections and interdependencies created by it.More specifically, the paper is about stem cells. Biotechnology in general has the power to capture the imagination. Within the field of biotechnology nothing seems more provocative...... and tantalizing than stem cells, in research, in medicine, or as products....

  2. Stem cells.

    Science.gov (United States)

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

    2007-01-01

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

  3. Host cells and cell banking.

    Science.gov (United States)

    Stacey, Glyn N; Merten, Otto-Wilhelm

    2011-01-01

    Gene therapy based on the use of viral vectors is entirely dependent on the use of animal cell lines, mainly of mammalian origin, but also of insect origin. As for any biotechnology product for clinical use, viral -vectors have to be produced with cells derived from an extensively characterized cell bank to maintain the appropriate standard for assuring the lowest risk for the patients to be treated. Although many different cell types and lines have been used for the production of viral vectors, HEK293 cells or their derivatives have been extensively used for production of different vector types: adenovirus, oncorectrovirus, lentivirus, and AAV vectors, because of their easy handling and the possibility to grow them adherently in serum-containing medium as well as in suspension in serum-free culture medium. Despite this, these cells are not necessarily the best for the production of a given viral vector, and there are many other cell lines with significant advantages including superior growth and/or production characteristics, which have been tested and also used for the production of clinical vector batches. This chapter presents basic -considerations concerning the characterization of cell banks, in the first part, and, in the second part, practically all cell lines (at least when public information was available) established and developed for the production of the most important viral vectors (adenoviral, oncoretroviral, lentiviral, AAV, baculovirus).

  4. Sickle cell anemia

    Science.gov (United States)

    ... Anemia - sickle cell; Hemoglobin SS disease (Hb SS); Sickle cell disease Images Red blood cells, sickle cell Red blood cells, normal Red blood ... multiple sickle cells Red blood cells, sickle cells Red blood cells, sickle and ... Heeney MM, Ware RE. Sickle cell disease. In: Orkin SH, Fisher DE, Ginsburg D, Look ...

  5. Establishment of indirect immunofluorescence assay for rotavirus.

    Science.gov (United States)

    Tao, J; Zhang, J; Liu, X; Jin, H; Jiang, C; Yin, Y

    2016-03-01

    Rotavirus infection is the most frequent cause of infantile gastroenteritis worldwide and a significant cause of death in infants and young children, following severe diarrhea and dehydration. Rotavirus vaccines are considered the most effective way to prevent rotavirus infections. In the process of developing rotavirus vaccines, it is crucial to establish a reliable and standardized method to determine vaccine titer. In this study, we developed an indirect immunofluorescence assay (IFA) to determine the infectious titer of Lanzhou lamb rotavirus (LLR) vaccine grown in MA104 cells. The activating concentration of trypsin was 1 µg/ml for healthy monolayers of MA104 cells at 100% confluence. After incubation for 18 hr, a rabbit anti-SA11 polyclonal antibody, diluted at 1:800 in PBS, was added to all wells, followed by an Alexa-488-conjugated secondary antibody diluted at 1:500 in PBS. Cells were examined with a fluorescence microscope. Our results show that IFA was more reproducible, more sensitive, simpler, and more rapid than the log 50% cell culture infectious dose-ELISA (lgCCID50-ELISA) in measuring the rotavirus vaccines. IFA provided a reliable basis for the qualitative and quantitative analysis of rotavirus, and the certification of rotavirus vaccine production.

  6. Cell, cell, cell: fuel cell applications moving ahead

    Energy Technology Data Exchange (ETDEWEB)

    Ross, E.

    2001-11-01

    Developments in fuel cell technology within the last decade, such as the targeting by major automakers of non-polluting fuel cells as an alternative to the internal combustion engine, are reviewed. For example, Ballard Power Systems of Vancouver is the exclusive supplier to both DaimlerCrysler and the Ford Motor Company of the fuel cell stacks that produce the power in fuel cell systems. Ballard plans the commercial launch of transit bus engines in 2002 and automotive products between 2003 and 2005. The company also sees huge opportunities for fuel cells in stationary and portable power applications. At the same time, the Calgary-based fuel cell division of Energy Ventures Inc. is developing a direct methanol fuel cell that eliminates the intermediate step of 'reforming' methanol into hydrogen that is required in the Ballard process. Energy Ventures targets small niche markets such as small utility vehicles for its direct methanol fuel cell. A completely self-contained fuel cell of this type is expected to be ready in 2002. Solid oxide fuel cells for off-grid remote power units as well as for home heat and power is yet another field of development that will be particularly attractive to operations in remote areas where reliable grid electricity is expensive and hard to obtain. A prototype 2.3 kW residential power system using natural gas was made available by Global Thermoelectric Inc in June 2001; field testing is planned for 2002, with commercial production in late 2003 or 2004. The Calgary-based Snow Leopard Resources Inc plans to use pure hydrogen sulphide obtained from sour natural gas as a hydrogen source. The prime focus of Snow Leopard is on gas plants looking for ways to increase their efficiency, obtain carbon dioxide credits and generate electricity on site. This type of fuel cell also could be of interest to companies with shut-in sour gas since these companies could use the stationary fuel cell system to generate electricity.

  7. Bi-Cell Unit for Fuel Cell.

    Science.gov (United States)

    The patent concerns a bi-cell unit for a fuel cell . The bi-cell unit is comprised of two electrode packs. Each of the electrode packs includes an...invention relates in general to a bi-cell unit for a fuel cell and in particular, to a bi-cell unit for a hydrazine-air fuel cell .

  8. Cy5 total protein normalization in Western blot analysis.

    Science.gov (United States)

    Hagner-McWhirter, Åsa; Laurin, Ylva; Larsson, Anita; Bjerneld, Erik J; Rönn, Ola

    2015-10-01

    Western blotting is a widely used method for analyzing specific target proteins in complex protein samples. Housekeeping proteins are often used for normalization to correct for uneven sample loads, but these require careful validation since expression levels may vary with cell type and treatment. We present a new, more reliable method for normalization using Cy5-prelabeled total protein as a loading control. We used a prelabeling protocol based on Cy5 N-hydroxysuccinimide ester labeling that produces a linear signal response. We obtained a low coefficient of variation (CV) of 7% between the ratio of extracellular signal-regulated kinase (ERK1/2) target to Cy5 total protein control signals over the whole loading range from 2.5 to 20.0μg of Chinese hamster ovary cell lysate protein. Corresponding experiments using actin or tubulin as controls for normalization resulted in CVs of 13 and 18%, respectively. Glyceraldehyde-3-phosphate dehydrogenase did not produce a proportional signal and was not suitable for normalization in these cells. A comparison of ERK1/2 signals from labeled and unlabeled samples showed that Cy5 prelabeling did not affect antibody binding. By using total protein normalization we analyzed PP2A and Smad2/3 levels with high confidence. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Learn About Stem Cells

    Science.gov (United States)

    ... Patient Handbook Stem Cell Glossary Search Toggle Nav Stem Cell Basics Stem cells are the foundation from which ... original cell’s DNA, cytoplasm and cell membrane. About stem cells Stem cells are the foundation of development in ...

  10. Fuel cells

    Directory of Open Access Journals (Sweden)

    D. N. Srivastava

    1962-05-01

    Full Text Available The current state of development of fuel cells as potential power sources is reviewed. Applications in special fields with particular reference to military requirements are pointed out.

  11. T Cells

    Science.gov (United States)

    ... Informed d Corporate Support Corporate Partners National Teams Partnership Opportunities d Personal Stories Ambassadors & Familiar Faces Life ... d Our Healthcare Voice Home What Is MS? Definition of MS T Cells Share this page Facebook ...

  12. Dry cell battery poisoning

    Science.gov (United States)

    Batteries - dry cell ... Acidic dry cell batteries contain: Manganese dioxide Ammonium chloride Alkaline dry cell batteries contain: Sodium hydroxide Potassium hydroxide Lithium dioxide dry cell batteries ...

  13. Electrochemical cell

    Science.gov (United States)

    Nagy, Zoltan; Yonco, Robert M.; You, Hoydoo; Melendres, Carlos A.

    1992-01-01

    An electrochemical cell has a layer-type or sandwich configuration with a Teflon center section that houses working, reference and counter electrodes and defines a relatively narrow electrolyte cavity. The center section is surrounded on both sides with thin Teflon membranes. The membranes are pressed in place by a pair of Teflon inner frames which are in turn supported by a pair of outer metal frames. The pair of inner and outer frames are provided with corresponding, appropriately shaped slits that are in plane generally transverse to the plane of the working electrode and permit X-ray beams to enter and exit the cell through the Teflon membranes that cover the slits so that the interface between the working electrode and the electrolyte within the cell may be analyzed by transmission geometry. In one embodiment, the center section consists of two parts, one on top of the other. Alternatively, the center section of the electrochemical cell may consist of two intersliding pieces or may be made of a single piece of Teflon sheet material. The electrolyte cavity is shaped so that the electrochemical cell can be rotated 90.degree. in either direction while maintaining the working and counter electrodes submerged in the electrolyte.

  14. Rotavirus detection and isolation from chickens with or without symptoms

    Directory of Open Access Journals (Sweden)

    LYB Villarreal

    2006-09-01

    Full Text Available Rotaviruses have been identified as one of the main etiological agents of diarrhea and enteritis in mammals, including humans, and in avian species. Few studies have been published about enteric viruses in Brazilian poultry, including those related to rotavirus infection. Such studies demonstrate significant occurrence and the importance of enteric viruses in poultry presenting intestinal problems. Enteric viruses are the primary cause of injuries to the gut, allowing other agents, especially bacteria, to attach, to penetrate, and to replicate in the enteric tissue, leading to further damage. The aim of the present study was to detect rotavirus in the intestinal contents of layers and broilers by polyacrylamide gel electrophoresis (PAGE and virus isolation in MA-104 cell culture. A total of 45.3% of all samples were positive to rotavirus; rotavirus frequencies were 48.7% in samples from flocks with diarrhea, 46.4% in flocks with delayed growth, and 30% in asymptomatic flocks. It was possible to isolate rotavirus in MA-104 cells from the nine rotavirus-positive randomly chosen samples. These results indicate that rotavirus may have an important role in pathogenesis of enteric disease.

  15. Fuel cells:

    DEFF Research Database (Denmark)

    Sørensen, Bent

    2013-01-01

    A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil and nucl......A brief overview of the progress in fuel cell applications and basic technology development is presented, as a backdrop for discussing readiness for penetration into the marketplace as a solution to problems of depletion, safety, climate or environmental impact from currently used fossil...... and nuclear fuel-based energy technologies....

  16. CellTracks cell analysis system for rare cell detection

    NARCIS (Netherlands)

    Kagan, Michael T.; Trainer, Michael N.; Bendele, Teresa; Rao, Chandra; Horton, Allen; Tibbe, Arjan G.; Greve, Jan; Terstappen, Leon W.M.M.

    2002-01-01

    The CellTracks system is a Compact Disk-based cell analyzer that, similar to flow cytometry, differentiates cells that are aligned while passing through focused laser beams. In CellTracks, only immuno-magnetically labeled cells are aligned and remain in position for further analysis. This feature is

  17. Tuning Collective Cell Migration by Cell-Cell Junction Regulation

    NARCIS (Netherlands)

    Friedl, P.; Mayor, R.

    2017-01-01

    Collective cell migration critically depends on cell-cell interactions coupled to a dynamic actin cytoskeleton. Important cell-cell adhesion receptor systems implicated in controlling collective movements include cadherins, immunoglobulin superfamily members (L1CAM, NCAM, ALCAM), Ephrin/Eph receptor

  18. Tuning Collective Cell Migration by Cell-Cell Junction Regulation

    NARCIS (Netherlands)

    Friedl, P.; Mayor, R.

    2017-01-01

    Collective cell migration critically depends on cell-cell interactions coupled to a dynamic actin cytoskeleton. Important cell-cell adhesion receptor systems implicated in controlling collective movements include cadherins, immunoglobulin superfamily members (L1CAM, NCAM, ALCAM), Ephrin/Eph

  19. Sickle Cell Anemia

    Science.gov (United States)

    Sickle cell anemia is a disease in which your body produces abnormally shaped red blood cells. The cells are shaped like ... normal, round red blood cells. This leads to anemia. The sickle cells also get stuck in blood ...

  20. Sickle Cell Disease

    Science.gov (United States)

    ... sickle cell disease?Sickle cell disease, also called sickle cell anemia, is a hereditary condition (which means it runs ... disease, hemoglobin SS disease, hemoglobin synthesis, hemoglobinopathies, ... cell anemia, sickle cell crisis, vaso-occlusive crisis Family Health, ...

  1. Characterization of cAMP accumulation mediated by three α1-adrenoceptor subtypes in HEK293 cells%α1-肾上腺素受体三种亚型介导的HEK293细胞中环腺苷-磷酸蓄积的特点

    Institute of Scientific and Technical Information of China (English)

    宋峣; 黄岩; 董尔丹; 韩启德; 张幼怡

    2003-01-01

    AIM: To investigate the characterization of cAMP response mediated by α1-adrenoceptor (α1-AR) subtypes inHEK293 cells. METHODS: (1) Full-length cDNA encoding three α1-AR subtypes were transfected into HEK293cells by the calcium phosphate precipitation method, respectively. (2) The densities of ci-AR subtypes expressedin HEK293 cells were measured by radioligand binding assay. (3) cAMP accumulation was measured by [3H]adenine prelabeling method. RESULTS: (1) Activation of each of three subtypes resulted in an increase of cAMPaccumulation in HEK293 cells in a dose-dependent manner, which was inhibited by selective α1-AR antagonistprazosin. (2) Comparing the pharmacological property, the maximal responses of α1A-AR to agonists were themost potent, while the sensitivity of α1-AR subtypes to norepinephrine (NE) was the highest. CONCLUSION:Each of three α1-AR subtypes can mediate cAMP accumulation in HEK293 cell line, and there are differences inpharmacological property.%目的:研究α1-肾上腺素受体各亚型介导的HEK293细胞中环腺苷一磷酸蓄积反应的特点.方法:(1)用磷酸钙沉淀法将编码三种亚型α1-肾上腺素受体的全长cDNA分别转染到HEK293细胞中.(2)采用放射配基结合实验测定各亚型α1肾上腺素受体在HEK293细胞的表达量.(3)用[3H]腺嘌呤掺入法测定环腺苷一磷酸蓄积率.结果:(1)各亚型激活后均使HEK293细胞中环腺苷一磷酸蓄积率呈浓度依赖性增加,并被α1-受体选择性拮抗剂哌唑嗪阻断.(2)比较各亚型的药理学特性发现,在三种亚型中,α1A-肾上腺素受体介导的效应最强,而α1-肾上腺素受体各亚型对去甲肾上腺素的敏感性最高.结论:三种亚型α1-肾上腺素受体均能介导HEK293细胞中环腺苷一磷酸的生成,并且在介导的效应和敏感性的高低等方面存在差异.

  2. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  3. Potent Cells

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    It seems hard to believe that Dolly the cloned sheep was born 10 years ago, kindling furious arguments over the prospects and ethics of cloning a human. Today, the controversy over cloning is entwined, often confused, with concerns over the use of human embryonic stem cells. Most people are unclear what cloning is, and they know even less when it…

  4. Electrochemical Cell

    DEFF Research Database (Denmark)

    1999-01-01

    The invention relates to a rechargeable electrochemical cell comprising a negative electrode, an electrolyte and a positive electrode in which the positive electrode structure comprises a lithium cobalt manganese oxide of the composition Li¿2?Co¿y?Mn¿2-y?O¿4? where 0

  5. Photovoltaic cell

    Science.gov (United States)

    Gordon, Roy G.; Kurtz, Sarah

    1984-11-27

    In a photovoltaic cell structure containing a visibly transparent, electrically conductive first layer of metal oxide, and a light-absorbing semiconductive photovoltaic second layer, the improvement comprising a thin layer of transition metal nitride, carbide or boride interposed between said first and second layers.

  6. Fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Enomoto, Hirofumi.

    1989-05-22

    This invention aims to maintain a long-term operation with stable cell output characteristics by uniformly supplying an electrolyte from the reserver to the matrix layer over the entire matrix layer, and further to prevent the excessive wetting of the catalyst layer by smoothly absorbing the volume change of the electrolyte, caused by the repeated stop/start-up of the fuel cell, within the reserver system. For this purpose, in this invention, an electrolyte transport layer, which connects with an electrolyte reservor formed at the electrode end, is partly formed between the electrode material and the catalyst layer; a catalyst layer, which faces the electrolyte transport layer, has through-holes, which connect to the matrix, dispersely distributed. The electrolyte-transport layer is a thin sheet of a hydrophilic fibers which are non-wovens of such fibers as carbon, silicon carbide, silicon nitride or inorganic oxides. 11 figs.

  7. Ghost cell lesions

    Directory of Open Access Journals (Sweden)

    E Rajesh

    2015-01-01

    Full Text Available Ghost cells have been a controversy for a long time. Ghost cell is a swollen/enlarged epithelial cell with eosnophilic cytoplasm, but without a nucleus. In routine H and E staining these cells give a shadowy appearance. Hence these cells are also called as shadow cells or translucent cells. The appearance of these cells varies from lesion to lesion involving odontogenic and nonodontogenic lesions. This article review about the origin, nature and significance of ghost cells in different neoplasms.

  8. [Inflammatory dendritic cells].

    Science.gov (United States)

    Segura, Elodie; Amigorena, Sebastian

    2014-01-01

    Dendritic cells are a rare and heterogeneous population of professional antigen-presenting cells. Several murine dendritic cell subpopulations have been identified that differ in their phenotype and functional properties. In the steady state, committed dendritic cell precursors differentiate into lymphoid organ-resident dendritic cells and migratory tissue dendritic cells. During inflammation appears an additional dendritic cell subpopulation that has been termed « inflammatory dendritic cells ». Inflammatory dendritic cells differentiate in situ from monocytes recruited to the site of inflammation. Here, we discuss how mouse inflammatory dendritic cells differ from macrophages and from other dendritic cell populations. Finally, we review recent work on human inflammatory dendritic cells.

  9. Red blood cells, sickle cell (image)

    Science.gov (United States)

    Sickle cell anemia is an inherited blood disease in which the red blood cells produce abnormal pigment (hemoglobin). ... abnormal hemoglobin causes deformity of the red blood cells into crescent or sickle-shapes, as seen in this photomicrograph.

  10. 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.

  11. CellFinder: a cell data repository

    OpenAIRE

    Stachelscheid, H.; Seltmann, S.; Lekschas, F.; Fontaine, J.F.; Mah, N.; Neves, M.; Andrade-Navarro, M.A.; Leser, U; Kurtz, A.

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue t...

  12. Molluscan cells in culture: primary cell cultures and cell lines

    OpenAIRE

    2013-01-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as bi...

  13. Electrorefining cell evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Bronson, M.C.; Thomas, R.L. (ed.)

    1989-04-14

    Operational characteristics of the LANL electrorefining cell, a modified LANL electrorefining cell, and an advanced electrorefining cell (known as the CRAC cell) were determined. Average process yields achieved were: 75% for the LANL cell, 82% for the modified LANL cell, and 86% for the CRAC cell. All product metal from the LANL and modified LANL cells was within foundry specifications. Metal from one run in the CRAC cell exceeded foundry specifications for tantalum. The LANL and modified LANL cells were simple in design and operation, but product separation was more labor intensive than with the CRAC cell. The CRAC cell was more complicated in design but remained relatively simple in operation. A decision analysis concluded that the modified LANL cell was the preferred cell. It was recommended that the modified LANL cell be implemented by the Plutonium Recovery Project at Rocky Flats and that development of the CRAC cell continue. 8 refs., 22 figs., 12 tabs.

  14. Antiparietal cell antibody test

    Science.gov (United States)

    APCA; Anti-gastric parietal cell antibody; Atrophic gastritis - anti-gastric parietal cell antibody; Gastric ulcer - anti-gastric parietal cell antibody; Pernicious anemia - anti-gastric parietal cell antibody; ...

  15. Sickle cell test

    Science.gov (United States)

    ... abnormal hemoglobin that causes sickle cell disease and sickle cell trait. Hemoglobin is a protein in red blood cells ... has two abnormal hemoglobin S genes. A person with sickle cell trait has only one of these abnormal genes and ...

  16. Molluscan cells in culture: primary cell cultures and cell lines.

    Science.gov (United States)

    Yoshino, T P; Bickham, U; Bayne, C J

    2013-06-01

    In vitro cell culture systems from molluscs have significantly contributed to our basic understanding of complex physiological processes occurring within or between tissue-specific cells, yielding information unattainable using intact animal models. In vitro cultures of neuronal cells from gastropods show how simplified cell models can inform our understanding of complex networks in intact organisms. Primary cell cultures from marine and freshwater bivalve and gastropod species are used as biomonitors for environmental contaminants, as models for gene transfer technologies, and for studies of innate immunity and neoplastic disease. Despite efforts to isolate proliferative cell lines from molluscs, the snail Biomphalaria glabrata Say, 1818 embryonic (Bge) cell line is the only existing cell line originating from any molluscan species. Taking an organ systems approach, this review summarizes efforts to establish molluscan cell cultures and describes the varied applications of primary cell cultures in research. Because of the unique status of the Bge cell line, an account is presented of the establishment of this cell line, and of how these cells have contributed to our understanding of snail host-parasite interactions. Finally, we detail the difficulties commonly encountered in efforts to establish cell lines from molluscs and discuss how these difficulties might be overcome.

  17. DNA-cell conjugates

    Science.gov (United States)

    Hsiao, Shih-Chia; Francis, Matthew B.; Bertozzi, Carolyn; Mathies, Richard; Chandra, Ravi; Douglas, Erik; Twite, Amy; Toriello, Nicholas; Onoe, Hiroaki

    2016-05-03

    The present invention provides conjugates of DNA and cells by linking the DNA to a native functional group on the cell surface. The cells can be without cell walls or can have cell walls. The modified cells can be linked to a substrate surface and used in assay or bioreactors.

  18. Optimizing cell viability in dropletbased cell deposition

    NARCIS (Netherlands)

    Hendriks, Jan; Visser, C.W.; Henke, S.J.; Leijten, Jeroen Christianus Hermanus; Saris, Daniël B.F.; Sun, Chao; Lohse, Detlef; Karperien, Hermanus Bernardus Johannes

    2015-01-01

    Biofabrication commonly involves the use of liquid droplets to transport cells to the printed structure. However, the viability of the cells after impact is poorly controlled and understood, hampering applications including cell spraying, inkjet bioprinting, and laser-assisted cell transfer. Here,

  19. Skin Stem Cells in Skin Cell Therapy

    Directory of Open Access Journals (Sweden)

    Mollapour Sisakht

    2015-12-01

    Full Text Available Context Preclinical and clinical research has shown that stem cell therapy is a promising therapeutic option for many diseases. This article describes skin stem cells sources and their therapeutic applications. Evidence Acquisition Compared with conventional methods, cell therapy reduces the surgical burden for patients because it is simple and less time-consuming. Skin cell therapy has been developed for variety of diseases. By isolation of the skin stem cell from the niche, in vitro expansion and transplantation of cells offers a surprising healing capacity profile. Results Stem cells located in skin cells have shown interesting properties such as plasticity, transdifferentiation, and specificity. Mesenchymal cells of the dermis, hypodermis, and other sources are currently being investigated to promote regeneration. Conclusions Because skin stem cells are highly accessible from autologous sources and their immunological profile is unique, they are ideal for therapeutic approaches. Optimization of administrative routes requires more investigation own to the lack of a standard protocol.

  20. Molecular Mechanisms of Cell-cell Recognition

    Institute of Scientific and Technical Information of China (English)

    WANG Jia-Huai

    2004-01-01

    Cell-cell recognition is the key for multicellular organisms to survive. This recognition critically depends on protein-protein interactions from opposing cell surfaces. Recent structural investigations reveal unique features of these cell surface receptors and how they interact. These interactions are specific, but usually relatively weak, with more hydrophilic forces involved in binding. The receptors appear to have specialized ways to present their key interacting elements for ligand-binding from the cell surface. Cell-cell contacts are multivalent. A large group of cell surface molecules are engaged in interactions. Characteristic weak interactions make possible for each individual molecule pair within the group to constantly associate-dissociate-reassociate, such that the cell-cell recognition becomes a dynamic process. The immunological synapse is a good example for immune receptors to be orchestrated in performing immunological function in a collective fashion.

  1. Photoelectrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Rauh, R. David (Newton, MA); Boudreau, Robert A. (Norton, MA)

    1983-06-14

    A photoelectrochemical cell comprising a sealed container having a light-transmitting window for admitting light into the container across a light-admitting plane, an electrolyte in the container, a photoelectrode in the container having a light-absorbing surface arranged to receive light from the window and in contact with the electrolyte, the surface having a plurality of spaced portions oblique to the plane, each portion having dimensions at least an order of magnitude larger than the maximum wavelength of incident sunlight, the total surface area of the surface being larger than the area of the plane bounded by the container, and a counter electrode in the container in contact with the electrolyte.

  2. NKT Cell Responses to B Cell Lymphoma

    Directory of Open Access Journals (Sweden)

    Junxin Li

    2014-04-01

    Full Text Available Natural killer T (NKT cells are a unique subset of CD1d-restricted T lymphocytes that express characteristics of both T cells and natural killer cells. NKT cells mediate tumor immune-surveillance; however, NKT cells are numerically reduced and functionally impaired in lymphoma patients. Many hematologic malignancies express CD1d molecules and co-stimulatory proteins needed to induce anti-tumor immunity by NKT cells, yet most tumors are poorly immunogenic. In this study, we sought to investigate NKT cell responses to B cell lymphoma. In the presence of exogenous antigen, both mouse and human NKT cell lines produce cytokines following stimulation by B cell lymphoma lines. NKT cell populations were examined ex vivo in mouse models of spontaneous B cell lymphoma, and it was found that during early stages, NKT cell responses were enhanced in lymphoma-bearing animals compared to disease-free animals. In contrast, in lymphoma-bearing animals with splenomegaly and lymphadenopathy, NKT cells were functionally impaired. In a mouse model of blastoid variant mantle cell lymphoma, treatment of tumor-bearing mice with a potent NKT cell agonist, α-galactosylceramide (α-GalCer, resulted in a significant decrease in disease pathology. Ex vivo studies demonstrated that NKT cells from α-GalCer treated mice produced IFN-γ following α-GalCer restimulation, unlike NKT cells from vehicle-control treated mice. These data demonstrate an important role for NKT cells in the immune response to an aggressive hematologic malignancy like mantle cell lymphoma.

  3. nduced pluripotent stem cells and cell therapy

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2013-12-01

    Full Text Available Human embryonic stem cells are derived from the inner cell mass of a blastocyst-stage embryo. They hold a huge promise for cell therapy with their self-renewing ability and pluripotency, which is known as the potential to differentiate into all cell types originating from three embryonic germ layers. However, their unique pluripotent feature could not be utilised for therapeutic purposes due to the ethical and legal problems during derivation. Recently, it was shown that the cells from adult tissues could be reverted into embryonic state, thereby restoring their pluripotent feature. This has strenghtened the possiblity of directed differentition of the reprogrammed somatic cells into the desired cell types in vitro and their use in regenerative medicine. Although these cells were termed as induced pluripotent cells, the mechanism of pluripotency has yet to be understood. Still, induced pluripotent stem cell technology is considered to be significant by proposing novel approaches in disease modelling, drug screening and cell therapy. Besides their self-renewing ability and their potential to differentiate into all cell types in a human body, they arouse a great interest in scientific world by being far from the ethical concerns regarding their embryonic counterparts and their unique feature of being patient-specific in prospective cell therapies. In this review, induced pluripotent stem cell technology and its role in cell-based therapies from past to present will be discussed. J Clin Exp Invest 2013; 4 (4: 550-561

  4. Modeling cell-in-cell structure into its biological significance

    OpenAIRE

    He, M-f; Wang, S.; Wang, Y; Wang, X-N.

    2013-01-01

    Although cell-in-cell structure was noted 100 years ago, the molecular mechanisms of ‘entering' and the destination of cell-in-cell remain largely unclear. It takes place among the same type of cells (homotypic cell-in-cell) or different types of cells (heterotypic cell-in-cell). Cell-in-cell formation affects both effector cells and their host cells in multiple aspects, while cell-in-cell death is under more intensive investigation. Given that cell-in-cell has an important role in maintainin...

  5. Tumor cell "dead or alive": caspase and survivin regulate cell death, cell cycle and cell survival.

    Science.gov (United States)

    Suzuki, A; Shiraki, K

    2001-04-01

    Cell death and cell cycle progression are two sides of the same coin, and these two different phenomenons are regulated moderately to maintain the cellular homeostasis. Tumor is one of the disease states produced as a result of the disintegrated regulation and is characterized as cells showing an irreversible progression of cell cycle and a resistance to cell death signaling. Several investigations have been performed for the understanding of cell death or cell cycle, and cell death research has remarkably progressed in these 10 years. Caspase is a nomenclature referring to ICE/CED-3 cysteine proteinase family and plays a central role during cell death. Recently, several investigations raised some possible hypotheses that caspase is also involved in cell cycle regulation. In this issue, therefore, we review the molecular basis of cell death and cell cycle regulated by caspase in tumor, especially hepatocellular carcinoma cells.

  6. Nanostructured Solar Cells.

    Science.gov (United States)

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-08-09

    We are glad to announce the Special Issue "Nanostructured Solar Cells", published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  7. Cell death pathways in directly irradiated cells and cells exposed to medium from irradiated cells.

    Science.gov (United States)

    Jella, Kishore Kumar; Garcia, Amaya; McClean, Brendan; Byrne, Hugh J; Lyng, Fiona M

    2013-03-01

    The aim of this study was to compare levels of apoptosis, necrosis, mitotic cell death and senescence after treatment with both direct radiation and irradiated cell conditioned medium. Human keratinocytes (HaCaT cell line) were irradiated (0.005, 0.05 and 0.5 Gy) using a cobalt 60 teletherapy unit. For bystander experiments, the medium was harvested from donor HaCaT cells 1 hour after irradiation and transferred to recipient HaCaT cells. Clonogenic assay, apoptosis, necrosis, mitotic cell death, senescence and cell cycle analysis were measured in both directly irradiated cells and bystander cells A reduction in cell survival was observed for both directly irradiated cells and irradiated cell conditioned medium (ICCM)-treated cells. Early apoptosis and necrosis was observed predominantly after direct irradiation. An increase in the number of cells in G2/M phase was observed at 6 and 12 h which led to mitotic cell death after 72 h following direct irradiation and ICCM treatment. No senescence was observed in the HaCaT cell line following either direct irradiation or treatment with ICCM. This study has shown that directly irradiated cells undergo apoptosis, necrosis and mitotic cell death whereas ICCM-treated cells predominantly undergo mitotic cell death.

  8. Cell culture purity issues and DFAT cells

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Shengjuan [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi Province 712100 (China); Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States); Bergen, Werner G. [Program in Cellular and Molecular Biosciences/Department of Animal Sciences, Auburn University, Auburn, AL 36849 (United States); Hausman, Gary J. [Animal Science Department, University of Georgia, Athens, GA 30602-2771 (United States); Zan, Linsen, E-mail: zanls@yahoo.com.cn [College of Animal Science and Technology, Northwest A and F University, Yangling, Shaanxi Province 712100 (China); Dodson, Michael V., E-mail: dodson@wsu.edu [Department of Animal Sciences, Washington State University, Pullman, WA 99164 (United States)

    2013-04-12

    Highlights: •DFAT cells are progeny cells derived from dedifferentiated mature adipocytes. •Common problems in this research is potential cell contamination of initial cultures. •The initial cell culture purity is crucial in DFAT cell research field. -- Abstract: Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  9. Electrochemical cell

    Energy Technology Data Exchange (ETDEWEB)

    Heuts, J.J.F.G.; Willems, J.J.G.S.A.

    1987-10-13

    An electrochemical cell is described comprising a negative electrode. The electrochemically active material of which consists of an intermetallic compound forming a hydride with hydrogen, which compound has the CaCu/sub 5/-structure and the compositional formula AB/sub m/C/sub n/, where m+n is between 4.8 and 5.4, where n is between 0.05 and 0.6, in which A consists of Misch-metal or of one or more elements selected from the group consisting of Y, Ti, Hf, Zr, Ca, Th, La and the remaining rare earth metals, in which the total atomic quantities of the elements Y, Ti, Hf and Zr may not be more than 40% of A. B consists of two or more elements selected from the group formed by Ni, Co, Cu, Fe and Mn, where the maximum atomic quantity per gram atom of A is for Ni: 3.5, for Co:3.5, for Cu:3.5, for Fe:2.0 and for Mn:1.0, and C consists of one or more elements selected from the group formed by Al, Cr and Si in the indicated atomic quantities: Al:0.05-0.6, Cr:0.05-0.5 and Si:0.05-0.5, characterized in that the electrochemically active material additionally comprises one or more metals selected from the group formed by Pd, Pt, Ir and Rh, the atomic quantity per gram atom of A being from 0.001 to 0.5.

  10. CELL RESEARCH

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    REVIEWSInducible resistance to Fas-mediated apoptosis in B cells…………………………………ROTHSTEIN Thomas L (245)Executionary pathway for apoptosis: lessons from mutant mice………………………………………WOO Minna, Razqallah Hakem, Tak W Mak (267)The SHP-2 tyrosine phosphatase: Signaling mechanisms and biological functions…………………………………QU Cheng Kui (279)REGULAR ARTICLESTemperature dependent expression of cdc2 and cyclin B1 in spermatogenic cells during spermatogenesis…………………………KONG Wei Hua, Zheng GU, Jining LU, Jiake TSO (289)Transgenic mice overexpressing γ-aminobutyric acid transporter subtype I develop obesity…………………………………MA Ying Hua, Jia Hua HU, Xiao Gang ZHOU, Ruo Wang ZENG, Zhen Tong MEI, Jian FEI, Li He GUO (303)Genetic aberration in primary hepatocellular carcinoma: correlation between p53 gene mutation and loss-of-heterozygosity on chromosome 16q21-q23 and 9p21-p23………………………………………WANG Gang, Chang Hui HUANG, Yan ZHAO, Ling CAI, Ying WANG, Shi Jin XIU, Zheng Wen JIANG, Shuang YANG, Xin Tai ZHAO, Wei HUANG, Jian Ren GU (311)Identification and genetic mapping of four novel genes that regulate leaf deve- lopment in Arabidopsis………………………………………………SUN Yue, Wei ZHANG, Feng Ling LI, Ying Li GUO, Tian Lei LIU, Hai HUANG (325)NOTICE FOR CONTRIBUTORS…………………………………(337)CONTENTS of Vol. 10, 2000…………………………………………………(338)

  11. Mammary stem cells have myoepithelial cell properties

    Science.gov (United States)

    Prater, Michael D.; Petit, Valérie; Russell, I. Alasdair; Giraddi, Rajshekhar; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F.; Metzger, Daniel; Faraldo, Marisa M.; Deugnier, Marie-Ange; Glukhova, Marina A.; Stingl, John

    2014-01-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt acin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using 2 independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage tracing approach we follow the progeny of α-smooth muscle actin-expressing myoepithelial cells and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy. PMID:25173976

  12. Mammary stem cells have myoepithelial cell properties.

    Science.gov (United States)

    Prater, Michael D; Petit, Valérie; Alasdair Russell, I; Giraddi, Rajshekhar R; Shehata, Mona; Menon, Suraj; Schulte, Reiner; Kalajzic, Ivo; Rath, Nicola; Olson, Michael F; Metzger, Daniel; Faraldo, Marisa M; Deugnier, Marie-Ange; Glukhova, Marina A; Stingl, John

    2014-10-01

    Contractile myoepithelial cells dominate the basal layer of the mammary epithelium and are considered to be differentiated cells. However, we observe that up to 54% of single basal cells can form colonies when seeded into adherent culture in the presence of agents that disrupt actin-myosin interactions, and on average, 65% of the single-cell-derived basal colonies can repopulate a mammary gland when transplanted in vivo. This indicates that a high proportion of basal myoepithelial cells can give rise to a mammary repopulating unit (MRU). We demonstrate that myoepithelial cells, flow-sorted using two independent myoepithelial-specific reporter strategies, have MRU capacity. Using an inducible lineage-tracing approach we follow the progeny of myoepithelial cells that express α-smooth muscle actin and show that they function as long-lived lineage-restricted stem cells in the virgin state and during pregnancy.

  13. Cell culture purity issues and DFAT cells.

    Science.gov (United States)

    Wei, Shengjuan; Bergen, Werner G; Hausman, Gary J; Zan, Linsen; Dodson, Michael V

    2013-04-12

    Dedifferentiation of mature adipocytes, in vitro, has been pursued/documented for over forty years. The subsequent progeny cells are named dedifferentiated adipocyte-derived progeny cells (DFAT cells). DFAT cells are proliferative and likely to possess mutilineage potential. As a consequence, DFAT cells and their progeny/daughter cells may be useful as a potential tool for various aspects of tissue engineering and as potential vectors for the alleviation of several disease states. Publications in this area have been increasing annually, but the purity of the initial culture of mature adipocytes has seldom been documented. Consequently, it is not always clear whether DFAT cells are derived from dedifferentiated mature (lipid filled) adipocytes or from contaminating cells that reside in an impure culture.

  14. Cell Membrane Softening in Cancer Cells

    Science.gov (United States)

    Schmidt, Sebastian; Händel, Chris; Käs, Josef

    Biomechanical properties are useful characteristics and regulators of the cell's state. Current research connects mechanical properties of the cytoskeleton to many cellular processes but does not investigate the biomechanics of the plasma membrane. We evaluated thermal fluctuations of giant plasma membrane vesicles, directly derived from the plasma membranes of primary breast and cervical cells and observed a lowered rigidity in the plasma membrane of malignant cells compared to non-malignant cells. To investigate the specific role of membrane rigidity changes, we treated two cell lines with the Acetyl-CoA carboxylase inhibitor Soraphen A. It changed the lipidome of cells and drastically increased membrane stiffness by up regulating short chained membrane lipids. These altered cells had a decreased motility in Boyden chamber assays. Our results indicate that the thermal fluctuations of the membrane, which are much smaller than the fluctuations driven by the cytoskeleton, can be modulated by the cell and have an impact on adhesion and motility.

  15. Cell sheet engineering

    Directory of Open Access Journals (Sweden)

    Masayuki Yamato

    2004-05-01

    Full Text Available We have developed ‘cell sheet engineering’ in order to avoid the limitations of tissue reconstruction using biodegradable scaffolds or single cell suspension injection. Our concept is tissue reconstruction, not from single cells, but from cell sheets. Cell sheets are prepared using temperature-responsive culture dishes. Temperature-responsive polymers are covalently grafted onto the dishes, allowing various types of cells to adhere and proliferate at 37°C. The cells spontaneously detach when the temperature is reduced below 32°C without the need for proteolytic enzymes. The confluent cells are noninvasively harvested as single, contiguous cell sheets with intact cell-cell junctions and deposited extracellular matrix (ECM. We have used these harvested cell sheets for various tissue reconstructions, including ocular surfaces, periodontal ligaments, cardiac patches, and bladder augmentation.

  16. Lung cancer - small cell

    Science.gov (United States)

    Cancer - lung - small cell; Small cell lung cancer; SCLC ... About 15% of all lung cancer cases are SCLC. Small cell lung cancer is slightly more common in men than women. Almost all cases of SCLC are ...

  17. Stem Cell Information: Glossary

    Science.gov (United States)

    ... Tips Info Center Research Topics Federal Policy Glossary Stem Cell Information General Information Clinical Trials Funding Information Current ... here Home » Glossary Back to top Glossary Adult stem cell Astrocyte Blastocoel Blastocyst Bone marrow stromal cells Bone ...

  18. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL)Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  19. GSPEL - Fuel Cell Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — The Fuel Cell Lab (FCL) Provides testing for technology readiness of fuel cell systems The FCL investigates, tests and verifies the performance of fuel-cell systems...

  20. Natural Killer Cell Memory

    National Research Council Canada - National Science Library

    O'Sullivan, Timothy E; Sun, Joseph C; Lanier, Lewis L

    2015-01-01

    Natural killer (NK) cells have historically been considered short-lived cytolytic cells that can rapidly respond against pathogens and tumors in an antigen-independent manner and then undergo cell death...

  1. Fuel cells: A survey

    Science.gov (United States)

    Crowe, B. J.

    1973-01-01

    A survey of fuel cell technology and applications is presented. The operating principles, performance capabilities, and limitations of fuel cells are discussed. Diagrams of fuel cell construction and operating characteristics are provided. Photographs of typical installations are included.

  2. CellFinder: a cell data repository.

    Science.gov (United States)

    Stachelscheid, Harald; Seltmann, Stefanie; Lekschas, Fritz; Fontaine, Jean-Fred; Mah, Nancy; Neves, Mariana; Andrade-Navarro, Miguel A; Leser, Ulf; Kurtz, Andreas

    2014-01-01

    CellFinder (http://www.cellfinder.org) is a comprehensive one-stop resource for molecular data characterizing mammalian cells in different tissues and in different development stages. It is built from carefully selected data sets stemming from other curated databases and the biomedical literature. To date, CellFinder describes 3394 cell types and 50 951 cell lines. The database currently contains 3055 microscopic and anatomical images, 205 whole-genome expression profiles of 194 cell/tissue types from RNA-seq and microarrays and 553 905 protein expressions for 535 cells/tissues. Text mining of a corpus of >2000 publications followed by manual curation confirmed expression information on ∼900 proteins and genes. CellFinder's data model is capable to seamlessly represent entities from single cells to the organ level, to incorporate mappings between homologous entities in different species and to describe processes of cell development and differentiation. Its ontological backbone currently consists of 204 741 ontology terms incorporated from 10 different ontologies unified under the novel CELDA ontology. CellFinder's web portal allows searching, browsing and comparing the stored data, interactive construction of developmental trees and navigating the partonomic hierarchy of cells and tissues through a unique body browser designed for life scientists and clinicians.

  3. Snail modulates cell metabolism in MDCK cells

    Energy Technology Data Exchange (ETDEWEB)

    Haraguchi, Misako, E-mail: haraguci@m3.kufm.kagoshima-u.ac.jp [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Indo, Hiroko P. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Iwasaki, Yasumasa [Health Care Center, Kochi University, Kochi 780-8520 (Japan); Iwashita, Yoichiro [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Fukushige, Tomoko [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Majima, Hideyuki J. [Department of Maxillofacial Radiology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Izumo, Kimiko; Horiuchi, Masahisa [Department of Environmental Medicine, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Kanekura, Takuro [Department of Dermatology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Furukawa, Tatsuhiko [Department of Molecular Oncology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan); Ozawa, Masayuki [Department of Biochemistry and Molecular Biology, Graduate School of Medical and Dental Sciences, Kagoshima University, Kagoshima 890-8544 (Japan)

    2013-03-22

    Highlights: ► MDCK/snail cells were more sensitive to glucose deprivation than MDCK/neo cells. ► MDCK/snail cells had decreased oxidative phosphorylation, O{sub 2} consumption and ATP content. ► TCA cycle enzyme activity, but not expression, was lower in MDCK/snail cells. ► MDCK/snail cells showed reduced PDH activity and increased PDK1 expression. ► MDCK/snail cells showed reduced expression of GLS2 and ACLY. -- Abstract: Snail, a repressor of E-cadherin gene transcription, induces epithelial-to-mesenchymal transition and is involved in tumor progression. Snail also mediates resistance to cell death induced by serum depletion. By contrast, we observed that snail-expressing MDCK (MDCK/snail) cells undergo cell death at a higher rate than control (MDCK/neo) cells in low-glucose medium. Therefore, we investigated whether snail expression influences cell metabolism in MDCK cells. Although gylcolysis was not affected in MDCK/snail cells, they did exhibit reduced pyruvate dehydrogenase (PDH) activity, which controls pyruvate entry into the tricarboxylic acid (TCA) cycle. Indeed, the activity of multiple enzymes involved in the TCA cycle was decreased in MDCK/snail cells, including that of mitochondrial NADP{sup +}-dependent isocitrate dehydrogenase (IDH2), succinate dehydrogenase (SDH), and electron transport Complex II and Complex IV. Consequently, lower ATP content, lower oxygen consumption and increased survival under hypoxic conditions was also observed in MDCK/snail cells compared to MDCK/neo cells. In addition, the expression and promoter activity of pyruvate dehydrogenase kinase 1 (PDK1), which phosphorylates and inhibits the activity of PDH, was increased in MDCK/snail cells, while expression levels of glutaminase 2 (GLS2) and ATP-citrate lyase (ACLY), which are involved in glutaminolysis and fatty acid synthesis, were decreased in MDCK/snail cells. These results suggest that snail modulates cell metabolism by altering the expression and activity of

  4. Cell aggregation and sedimentation.

    Science.gov (United States)

    Davis, R H

    1995-01-01

    The aggregation of cells into clumps or flocs has been exploited for decades in such applications as biological wastewater treatment, beer brewing, antibiotic fermentation, and enhanced sedimentation to aid in cell recovery or retention. More recent research has included the use of cell aggregation and sedimentation to selectively separate subpopulations of cells. Potential biotechnological applications include overcoming contamination, maintaining plasmid-bearing cells in continuous fermentors, and selectively removing nonviable hybridoma cells from perfusion cultures.

  5. Cell control report

    CERN Document Server

    2013-01-01

    Please note this is a Short Discount publication. This extensive report provides an essential overview of cells and their use as factory automation building blocks. The following issues are discussed in depth: Cell integration Cell software and standards Future technologies applied to cells Plus Cell control applications including: - rotary parts manufacturing - diesel engine component development - general cell control development at the General Electric Corporation - a vendor list.

  6. Nanostructured Solar Cells

    Science.gov (United States)

    Chen, Guanying; Ning, Zhijun; Ågren, Hans

    2016-01-01

    We are glad to announce the Special Issue “Nanostructured Solar Cells”, published in Nanomaterials. This issue consists of eight articles, two communications, and one review paper, covering major important aspects of nanostructured solar cells of varying types. From fundamental physicochemical investigations to technological advances, and from single junction solar cells (silicon solar cell, dye sensitized solar cell, quantum dots sensitized solar cell, and small molecule organic solar cell) to tandem multi-junction solar cells, all aspects are included and discussed in this issue to advance the use of nanotechnology to improve the performance of solar cells with reduced fabrication costs.

  7. Squamous cell skin cancer

    Science.gov (United States)

    ... that reflect light more, such as water, sand, concrete, and areas that are painted white. The higher ... - skin - squamous cell; Skin cancer - squamous cell; Nonmelanoma skin cancer - squamous ...

  8. Cell mechanics: a dialogue

    Science.gov (United States)

    Tao, Jiaxiang; Li, Yizeng; Vig, Dhruv K.; Sun, Sean X.

    2017-03-01

    Under the microscope, eukaryotic animal cells can adopt a variety of different shapes and sizes. These cells also move and deform, and the physical mechanisms driving these movements and shape changes are important in fundamental cell biology, tissue mechanics, as well as disease biology. This article reviews some of the basic mechanical concepts in cells, emphasizing continuum mechanics description of cytoskeletal networks and hydrodynamic flows across the cell membrane. We discuss how cells can generate movement and shape changes by controlling mass fluxes at the cell boundary. These mass fluxes can come from polymerization/depolymerization of actin cytoskeleton, as well as osmotic and hydraulic pressure-driven flow of water across the cell membrane. By combining hydraulic pressure control with force balance conditions at the cell surface, we discuss a quantitative mechanism of cell shape and volume control. The broad consequences of this model on cell mechanosensation and tissue mechanics are outlined.

  9. Cell surface engineering of mesenchymal stem cells.

    Science.gov (United States)

    Sarkar, Debanjan; Zhao, Weian; Gupta, Ashish; Loh, Wei Li; Karnik, Rohit; Karp, Jeffrey M

    2011-01-01

    By leveraging the capacity to promote regeneration, stem cell therapies offer enormous hope for solving some of the most tragic illnesses, diseases, and tissue defects world-wide. However, a significant barrier to the effective implementation of cell therapies is the inability to target a large quantity of viable cells with high efficiency to tissues of interest. Systemic infusion is desired as it minimizes the invasiveness of cell therapy, and maximizes practical aspects of repeated doses. However, cell types such as mesenchymal stem cells exhibit a poor homing capability or lose their capacity to home following culture expansion (i.e. FASEB J 21:3197-3207, 2007; Circulation 108:863-868, 2003; Stroke: A Journal of Cerebral Circulation 32:1005-1011; Blood 104:3581-3587, 2004). To address this challenge, we have developed a simple platform technology to chemically attach cell adhesion molecules to the cell surface to improve the homing efficiency to specific tissues. This chemical approach involves a stepwise process including (1) treatment of cells with sulfonated biotinyl-N-hydroxy-succinimide to introduce biotin groups on the cell surface, (2) addition of streptavidin that binds to the biotin on the cell surface and presents unoccupied binding sites, and (3) attachment of biotinylated targeting ligands that promote adhesive interactions with vascular endothelium. Specifically, in our model system, a biotinylated cell rolling ligand, sialyl Lewisx (SLeX), found on the surface of leukocytes (i.e., the active site of the P-selectin glycoprotein ligand (PSGL-1)), is conjugated on MSC surface. The SLeX engineered MSCs exhibit a rolling response on a P-selectin coated substrate under shear stress conditions. This indicates that this approach can be used to potentially target P-selectin expressing endothelium in the more marrow or at sites of inflammation. Importantly, the surface modification has no adverse impact on MSCs' native phenotype including their multilineage

  10. Biological activity of Serratia marcescens cytotoxin

    Directory of Open Access Journals (Sweden)

    G.V. Carbonell

    2003-03-01

    Full Text Available Serratia marcescens cytotoxin was purified to homogeneity by ion-exchange chromatography on a DEAE Sepharose Fast Flow column, followed by gel filtration chromatography on a Sephadex G100 column. The molecular mass of the cytotoxin was estimated to be about 50 kDa. Some biological properties of the cytotoxin were analyzed and compared with well-characterized toxins, such as VT1, VT2 and CNF from Escherichia coli and hemolysin produced by S. marcescens. The sensitivity of the cell lines CHO, HeLa, HEp-2, Vero, BHK-21, MA 104 and J774 to the cytotoxin was determined by the cell viability assay using neutral red. CHO and HEp-2 were highly sensitive, with massive cellular death after 1 h of treatment, followed by BHK-21, HeLa, Vero and J774 cells, while MA 104 was insensitive to the toxin. Cytotoxin induced morphological changes such as cell rounding with cytoplasmic retraction and nuclear compactation which were evident 15 min after the addition of cytotoxin. The cytotoxic assays show that 15 min of treatment with the cytotoxin induced irreversible intoxication of the cells, determined by loss of cell viability. Concentrations of 2 CD50 (0.56 µg/ml of purified cytotoxin did not present any hemolytic activity, showing that the cytotoxin is distinct from S. marcescens hemolysin. Antisera prepared against S. marcescens cytotoxin did not neutralize the cytotoxic activity of VT1, VT2 or CNF toxin, indicating that these toxins do not share antigenic determinants with cytotoxin. Moreover, we did not detect gene sequences for any of these toxins in S. marcescens by PCR assay. These results suggest that S. marcescens cytotoxin is not related to any of these toxins from E. coli.

  11. Biological activity of Serratia marcescens cytotoxin.

    Science.gov (United States)

    Carbonell, G V; Amorim, C R N; Furumura, M T; Darini, A L C; Fonseca, B A L; Yano, T

    2003-03-01

    Serratia marcescens cytotoxin was purified to homogeneity by ion-exchange chromatography on a DEAE Sepharose Fast Flow column, followed by gel filtration chromatography on a Sephadex G100 column. The molecular mass of the cytotoxin was estimated to be about 50 kDa. Some biological properties of the cytotoxin were analyzed and compared with well-characterized toxins, such as VT1, VT2 and CNF from Escherichia coli and hemolysin produced by S. marcescens. The sensitivity of the cell lines CHO, HeLa, HEp-2, Vero, BHK-21, MA 104 and J774 to the cytotoxin was determined by the cell viability assay using neutral red. CHO and HEp-2 were highly sensitive, with massive cellular death after 1 h of treatment, followed by BHK-21, HeLa, Vero and J774 cells, while MA 104 was insensitive to the toxin. Cytotoxin induced morphological changes such as cell rounding with cytoplasmic retraction and nuclear compactation which were evident 15 min after the addition of cytotoxin. The cytotoxic assays show that 15 min of treatment with the cytotoxin induced irreversible intoxication of the cells, determined by loss of cell viability. Concentrations of 2 CD50 (0.56 g/ml) of purified cytotoxin did not present any hemolytic activity, showing that the cytotoxin is distinct from S. marcescens hemolysin. Antisera prepared against S. marcescens cytotoxin did not neutralize the cytotoxic activity of VT1, VT2 or CNF toxin, indicating that these toxins do not share antigenic determinants with cytotoxin. Moreover, we did not detect gene sequences for any of these toxins in S. marcescens by PCR assay. These results suggest that S. marcescens cytotoxin is not related to any of these toxins from E. coli.

  12. Cancer stem cell-like cells from a single cell of oral squamous carcinoma cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Felthaus, O. [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany); Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Ettl, T.; Gosau, M.; Driemel, O. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Brockhoff, G. [Department of Gynecology and Obstetrics, University of Regensburg (Germany); Reck, A. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Zeitler, K. [Institute of Pathology, University of Regensburg (Germany); Hautmann, M. [Department of Radiotherapy, University of Regensburg (Germany); Reichert, T.E. [Department of Oral and Maxillofacial Surgery, University of Regensburg (Germany); Schmalz, G. [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany); Morsczeck, C., E-mail: christian.morsczeck@klinik.uni-regensburg.de [Department of Operative Dentistry and Periodontology, University of Regensburg (Germany)

    2011-04-01

    Research highlights: {yields} Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). {yields} Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. {yields} Monoclonal cell lines showed reduced sensitivity for Paclitaxel. {yields} In situ CD133{sup +} cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. {yields} CD133{sup +} and CSC-like cells can be obtained from single colony forming cells of OSCCL. -- Abstract: Resistance of oral squamous cell carcinomas (OSCC) to conventional chemotherapy or radiation therapy might be due to cancer stem cells (CSCs). The development of novel anticancer drugs requires a simple method for the enrichment of CSCs. CSCs can be enriched from OSCC cell lines, for example, after cultivation in serum-free cell culture medium (SFM). In our study, we analyzed four OSCC cell lines for the presence of CSCs. CSC-like cells could not be enriched with SFM. However, cell lines obtained from holoclone colonies showed CSC-like properties such as a reduced rate of cell proliferation and a reduced sensitivity to Paclitaxel in comparison to cells from the parental lineage. Moreover, these cell lines differentially expressed the CSC-marker CD133, which is also upregulated in OSCC tissues. Interestingly, CD133{sup +} cells in OSCC tissues expressed little to no Ki67, the cell proliferation marker that also indicates reduced drug sensitivity. Our study shows a method for the isolation of CSC-like cell lines from OSCC cell lines. These CSC-like cell lines could be new targets for the development of anticancer drugs under in vitro conditions.

  13. Insect Cell Culture

    NARCIS (Netherlands)

    Oers, van M.M.; Lynn, D.E.

    2010-01-01

    Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from lepidoptera

  14. Tracking adult stem cells

    NARCIS (Netherlands)

    Snippert, H.J.G.; Clevers, H.

    2011-01-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context,

  15. Insect Cell Culture

    NARCIS (Netherlands)

    Oers, van M.M.; Lynn, D.E.

    2010-01-01

    Insect cell cultures are widely used in studies on insect cell physiology, developmental biology and microbial pathology. In particular, insect cell culture is an indispensable tool for the study of insect viruses. The first continuously growing insect cell cultures were established from lepidoptera

  16. T-Cell Lymphoma

    Science.gov (United States)

    Getting the Facts T-Cell Lymphoma Overview Lymphoma is the most common blood cancer. The two main forms of lymphoma are Hodgkin lymphoma ... develop into lymphomas: B-lymphocytes (B-cells) and T-lymphocytes (T-cells). T-cell lymphomas account for ...

  17. 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.

  18. Individual cell sorting.

    Science.gov (United States)

    Stovel, R T; Sweet, R G

    1979-01-01

    Current cell sorting machines do not preserve the individual identity of processed cells; after analysis, the cells are assigned to a subpopulation where they are pooled with other similar cells. This paper reports progress on a system that sorts cells individually to precise locations on a microscope slide and preserves them for further observation with a light microscope while recording flow measurement data for each cell. Various electronic and mechanical modifications to an existing sorting machine are described that increase drop placement accuracy and permit individual cell sorting.

  19. Stem Cell Organoid Engineering

    Science.gov (United States)

    Yin, Xiaolei; Mead, Benjamin E.; Safaee, Helia; Langer, Robert; Karp, Jeffrey M.; Levy, Oren

    2016-01-01

    Organoid systems leverage the self-organizing properties of stem cells to create diverse multi-cellular tissue proxies. Most organoid models only represent single or partial components of a tissue, and it is often difficult to control the cell type, organization, and cell-cell/cell-matrix interactions within these systems. Herein, we discuss basic approaches to generate stem cell-based organoids, their advantages and limitations, and how bioengineering strategies can be used to steer the cell composition and their 3D organization within organoids to further enhance their utility in research and therapies. PMID:26748754

  20. Molten carbonate fuel cell

    Science.gov (United States)

    Kaun, T.D.; Smith, J.L.

    1986-07-08

    A molten electrolyte fuel cell is disclosed with an array of stacked cells and cell enclosures isolating each cell except for access to gas manifolds for the supply of fuel or oxidant gas or the removal of waste gas. The cell enclosures collectively provide an enclosure for the array and effectively avoid the problems of electrolyte migration and the previous need for compression of stack components. The fuel cell further includes an inner housing about and in cooperation with the array enclosure to provide a manifold system with isolated chambers for the supply and removal of gases. An external insulated housing about the inner housing provides thermal isolation to the cell components.

  1. Innate Memory T cells

    Science.gov (United States)

    Jameson, Stephen C.; Lee, You Jeong; Hogquist, Kristin A.

    2015-01-01

    Memory T cells are usually considered to be a feature of a successful immune response against a foreign antigen, and such cells can mediate potent immunity. However, in mice, alternative pathways have been described, through which naïve T cells can acquire the characteristics and functions of memory T cells without encountering specific foreign antigen or the typical signals required for conventional T cell differentiation. Such cells reflect a response to the internal rather the external environment, and hence such cells are called innate memory T cells. In this review, we describe how innate memory subsets were identified, the signals that induce their generation and their functional properties and potential role in the normal immune response. The existence of innate memory T cells in mice raises questions about whether parallel populations exist in humans, and we discuss the evidence for such populations during human T cell development and differentiation. PMID:25727290

  2. Chicken NK cell receptors.

    Science.gov (United States)

    Straub, Christian; Neulen, Marie-Luise; Sperling, Beatrice; Windau, Katharina; Zechmann, Maria; Jansen, Christine A; Viertlboeck, Birgit C; Göbel, Thomas W

    2013-11-01

    Natural killer cells are innate immune cells that destroy virally infected or transformed cells. They recognize these altered cells by a plethora of diverse receptors and thereby differ from other lymphocytes that use clonally distributed antigen receptors. To date, several receptor families that play a role in either activating or inhibiting NK cells have been identified in mammals. In the chicken, NK cells have been functionally and morphologically defined, however, a conclusive analysis of receptors involved in NK cell mediated functions has not been available. This is partly due to the low frequencies of NK cells in blood or spleen that has hampered their intensive characterization. Here we will review recent progress regarding the diverse NK cell receptor families, with special emphasis on novel families identified in the chicken genome with potential as chicken NK cell receptors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Ganglion cell like cells, diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Anand Shankar Ammanagi

    2013-01-01

    Full Text Available We report a case of cutaneous swelling found on the left anterior axillary fold of a 41-year-old man. Gross examination of specimen excised from the dermis showed a well-circumscribed nodule histologically composed of spindle cells with interspersed ganglion cell like cells. On hematoxylin and eosine (H and E staining it was diagnosed as ganglioneuroma. Ganglioneuromas are rare, benign, fully differentiated tumors that contain mature schwann cells, ganglion cells, fibrous tissue, and nerve fibers. They are commonly found along the paravertebral sympathetic ganglia and sometimes in the adrenal medulla. However primary cutaneous ganglioneuroma is an extremely rare tumor. Immunohistochemical workup revealed a fibroblastic origin and hence the case was diagnosed as fibromatosis with ganglion cell like fibroblasts. This case report suggests that the features considered diagnostic of ganglioneuromas can occur in other cutaneous lesions and, therefore, this diagnosis cannot be offered only on the basis of H and E.

  4. 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.

  5. B cell helper assays.

    Science.gov (United States)

    Abrignani, Sergio; Tonti, Elena; Casorati, Giulia; Dellabona, Paolo

    2009-01-01

    Activation, proliferation and differentiation of naïve B lymphocytes into memory B cells and plasma cells requires engagement of the B cell receptor (BCR) coupled to T-cell help (1, 2). T cells deliver help in cognate fashion when they are activated upon recognition of specific MHC-peptide complexes presented by B cells. T cells can also deliver help in a non-cognate or bystander fashion, when they do not find specific MHC-peptide complexes on B cells and are activated by alternative mechanisms. T-cell dependent activation of B cells can be studied in vitro by experimental models called "B cell helper assays" that are based on the co-culture of B cells with activated T cells. These assays allow to decipher the molecular bases for productive T-dependent B cell responses. We show here examples of B cell helper assays in vitro, which can be reproduced with any subset of T lymphocytes that displays the appropriate helper signals.

  6. Mast cells enhance T cell activation: Importance of mast cell-derived TNF

    Science.gov (United States)

    Nakae, Susumu; Suto, Hajime; Kakurai, Maki; Sedgwick, Jonathon D.; Tsai, Mindy; Galli, Stephen J.

    2005-05-01

    Mast cells are not only important effector cells in immediate hypersensitivity reactions and immune responses to pathogens but also can contribute to T cell-mediated disorders. However, the mechanisms by which mast cells might influence T cells in such settings are not fully understood. We find that mast cells can enhance proliferation and cytokine production in multiple T cell subsets. Mast cell-dependent enhancement of T cell activation can be promoted by FcRI-dependent mast cell activation, TNF production by both mast cells and T cells, and mast cell-T cell contact. However, at high concentrations of cells, mast cells can promote T cell activation independent of IgE or TNF. Finally, mast cells also can promote T cell activation by means of soluble factors. These findings identify multiple mechanisms by which mast cells can influence T cell proliferation and cytokine production. allergy | asthma | autoimmunity | cytokines | immune response

  7. Single cell mechanics of keratinocyte cells.

    Science.gov (United States)

    Lulevich, Valentin; Yang, Hsin-ya; Isseroff, R Rivkah; Liu, Gang-yu

    2010-11-01

    Keratinocytes represent the major cell type of the uppermost layer of human skin, the epidermis. Using AFM-based single cell compression, the ability of individual keratinocytes to resist external pressure and global rupturing forces is investigated and compared with various cell types. Keratinocytes are found to be 6-70 times stiffer than other cell types, such as white blood, breast epithelial, fibroblast, or neuronal cells, and in contrast to other cell types they retain high mechanic strength even after the cell's death. The absence of membrane rupturing peaks in the force-deformation profiles of keratinocytes and their high stiffness during a second load cycle suggests that their unique mechanical resistance is dictated by the cytoskeleton. A simple analytical model enables the quantification of Young's modulus of keratinocyte cytoskeleton, as high as 120-340 Pa. Selective disruption of the two major cytoskeletal networks, actin filaments and microtubules, does not significantly affect keratinocyte mechanics. F-actin is found to impact cell deformation under pressure. During keratinocyte compression, the plasma membrane stretches to form peripheral blebs. Instead of blebbing, cells with depolymerized F-actin respond to pressure by detaching the plasma membrane from the cytoskeleton underneath. On the other hand, the compression force of keratinocytes expressing a mutated keratin (cell line, KEB-7) is 1.6-2.2 times less than that for the control cell line that has normal keratin networks. Therefore, we infer that the keratin intermediate filament network is responsible for the extremely high keratinocyte stiffness and resilience. This could manifest into the rugged protective nature of the human epidermis.

  8. Lung Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Sharon R. Pine

    2008-01-01

    Full Text Available Lung cancer remains a major cause of cancer-related lethality because of high incidence and recurrence in spite of significant advances in staging and therapies. Recent data indicates that stem cells situated throughout the airways may initiate cancer formation. These putative stem cells maintain protumorigenic characteristics including high proliferative capacity, multipotent differentiation, drug resistance and long lifespan relative to other cells. Stem cell signaling and differentiation pathways are maintained within distinct cancer types, and destabilization of this machinery may participate in maintenance of cancer stem cells. Characterization of lung cancer stem cells is an area of active research and is critical for developing novel therapies. This review summarizes the current knowledge on stem cell signaling pathways and cell markers used to identify the lung cancer stem cells.

  9. Tracking adult stem cells.

    Science.gov (United States)

    Snippert, Hugo J; Clevers, Hans

    2011-02-01

    The maintenance of stem-cell-driven tissue homeostasis requires a balance between the generation and loss of cell mass. Adult stem cells have a close relationship with the surrounding tissue--known as their niche--and thus, stem-cell studies should preferably be performed in a physiological context, rather than outside their natural environment. The mouse is an attractive model in which to study adult mammalian stem cells, as numerous experimental systems and genetic tools are available. In this review, we describe strategies commonly used to identify and functionally characterize adult stem cells in mice and discuss their potential, limitations and interpretations, as well as how they have informed our understanding of adult stem-cell biology. An accurate interpretation of physiologically relevant stem-cell assays is crucial to identify adult stem cells and elucidate how they self-renew and give rise to differentiated progeny.

  10. Plant stem cell niches.

    Science.gov (United States)

    Aichinger, Ernst; Kornet, Noortje; Friedrich, Thomas; Laux, Thomas

    2012-01-01

    Multicellular organisms possess pluripotent stem cells to form new organs, replenish the daily loss of cells, or regenerate organs after injury. Stem cells are maintained in specific environments, the stem cell niches, that provide signals to block differentiation. In plants, stem cell niches are situated in the shoot, root, and vascular meristems-self-perpetuating units of organ formation. Plants' lifelong activity-which, as in the case of trees, can extend over more than a thousand years-requires that a robust regulatory network keep the balance between pluripotent stem cells and differentiating descendants. In this review, we focus on current models in plant stem cell research elaborated during the past two decades, mainly in the model plant Arabidopsis thaliana. We address the roles of mobile signals on transcriptional modules involved in balancing cell fates. In addition, we discuss shared features of and differences between the distinct stem cell niches of Arabidopsis.

  11. What are Stem Cells?

    Directory of Open Access Journals (Sweden)

    Ahmadshah Farhat

    2014-05-01

    Full Text Available   Stem cells are undifferentiated self regenerating multi potential cells. There are three types of stem cells categories by the ability to form after cells and correlated with the body’s development process. Totipotent: these stem cells can form an entire organism such as fertilized egg. Ploripotent: ploripotent cells are those that can form any cell in the body but cannot form an entire organism such as developing embryo’s totipotent cells become ploripotent  Multipotent: Multi potent stem cells are those that can only form specific cells in the body such as blood cells based. Based on the sources of stem cells we have three types of these cells: Autologous: Sources of the patient own cells are (Autologous either the cells from patient own body or his or her cord blood. For this type of transplant the physician now usually collects the periphery rather than morrow because the procedure is easier on like a bane morrow harvest it take place outside of an operating room, and the patient does not to be under general unsetting . Allogenic: Sources of stem cells from another donore are primarily relatives (familial allogenic or completely unrelated donors. Xenogenic: In these stem cells from different species are transplanted e .g striatal porcine fetal mesan cephalic (FVM xenotransplants for Parkinson’s disease. On sites of isolation such as embryo, umbilical cord and other body tissues stem cells are named embnyonic, cord blood, and adult stem cells. The scope of results and clinical application of stem cells are such as: Neurodegenerative conditions (MS,ALS, Parkinson’s, Stroke, Ocular disorders- Glaucoma, retinitis Pigmentosa (RP, Auto Immune Conditions (Lupus, MS,R. arthritis, Diabetes, etc, Viral Conditions (Hepatitis C and AIDS, Heart Disease, Adrenal Disorders, Injury(Nerve, Brain, etc, Anti aging (hair, skin, weight control, overall well being/preventive, Emotional disorders, Organ / Tissue Cancers, Blood cancers, Blood diseases

  12. Tetraspanins in Cell Migration

    Science.gov (United States)

    Jiang, Xupin; Zhang, Jiaping; Huang, Yuesheng

    2015-01-01

    Tetraspanins are a superfamily of small transmembrane proteins that are expressed in almost all eukaryotic cells. Through interacting with one another and with other membrane and intracellular proteins, tetraspanins regulate a wide range of proteins such as integrins, cell surface receptors, and signaling molecules, and thereby engage in diverse cellular processes ranging from cell adhesion and migration to proliferation and differentiation. In particular, tetraspanins modulate the function of proteins involved in all determining factors of cell migration including cell–cell adhesion, cell–ECM adhesion, cytoskeletal protrusion/contraction, and proteolytic ECM remodeling. We herein provide a brief overview of collective in vitro and in vivo studies of tetraspanins to illustrate their regulatory functions in the migration and trafficking of cancer cells, vascular endothelial cells, skin cells (keratinocytes and fibroblasts), and leukocytes. We also discuss the involvement of tetraspanins in various pathologic and remedial processes that rely on cell migration and their potential value as targets for therapeutic intervention. PMID:26091149

  13. Stem cells in urology.

    Science.gov (United States)

    Aboushwareb, Tamer; Atala, Anthony

    2008-11-01

    The shortage of donors for organ transplantation has stimulated research on stem cells as a potential resource for cell-based therapy in all human tissues. Stem cells have been used for regenerative medicine applications in many organ systems, including the genitourinary system. The potential applications for stem cell therapy have, however, been restricted by the ethical issues associated with embryonic stem cell research. Instead, scientists have explored other cell sources, including progenitor and stem cells derived from adult tissues and stem cells derived from the amniotic fluid and placenta. In addition, novel techniques for generating stem cells in the laboratory are being developed. These techniques include somatic cell nuclear transfer, in which the nucleus of an adult somatic cell is placed into an oocyte, and reprogramming of adult cells to induce stem-cell-like behavior. Such techniques are now being used in tissue engineering applications, and some of the most successful experiments have been in the field of urology. Techniques to regenerate bladder tissue have reached the clinic, and exciting progress is being made in other areas, such as regeneration of the kidney and urethra. Cell therapy as a treatment for incontinence and infertility might soon become a reality. Physicians should be optimistic that regenerative medicine and tissue engineering will one day provide mainstream treatment options for urologic disorders.

  14. Apigenin inhibits renal cell carcinoma cell proliferation.

    Science.gov (United States)

    Meng, Shuai; Zhu, Yi; Li, Jiang-Feng; Wang, Xiao; Liang, Zhen; Li, Shi-Qi; Xu, Xin; Chen, Hong; Liu, Ben; Zheng, Xiang-Yi; Xie, Li-Ping

    2017-03-21

    Apigenin, a natural flavonoid found in vegetables and fruits, has antitumor activity in several cancer types. The present study evaluated the effects and mechanism of action of apigenin in renal cell carcinoma (RCC) cells. We found that apigenin suppressed ACHN, 786-0, and Caki-1 RCC cell proliferation in a dose- and time-dependent manner. A comet assay suggested that apigenin caused DNA damage in ACHN cells, especially at higher doses, and induced G2/M phase cell cycle arrest through ATM signal modulation. Small interfering RNA (siRNA)-mediated p53 knockdown showed that apigenin-induced apoptosis was likely p53 dependent. Apigenin anti-proliferative effects were confirmed in an ACHN cell xenograft mouse model. Apigenin treatment reduced tumor growth and volume in vivo, and immunohistochemical staining revealed lower Ki-67 indices in tumors derived from apigenin-treated mice. These findings suggest that apigenin exposure induces DNA damage, G2/M phase cell cycle arrest, p53 accumulation and apoptosis, which collectively suppress ACHN RCC cell proliferation in vitro and in vivo. Given its antitumor effects and low in vivo toxicity, apigenin is a highly promising agent for treatment of RCC.

  15. Cell shape recognition by colloidal cell imprints

    NARCIS (Netherlands)

    Borovička, Josef; Stoyanov, S.D.; Paunov, V.N.

    2015-01-01

    The results presented in this study are aimed at the theoretical estimate of the interactions between a spherical microbial cell and the colloidal cell imprints in terms of the Derjaguin, Landau, Vervey, and Overbeek (DLVO) surface forces. We adapted the Derjaguin approximation to take into accou

  16. Are mesenchymal stromal cells immune cells?

    NARCIS (Netherlands)

    M.J. Hoogduijn (Martin)

    2015-01-01

    textabstractMesenchymal stromal cells (MSCs) are considered to be promising agents for the treatment of immunological disease. Although originally identified as precursor cells for mesenchymal lineages, in vitro studies have demonstrated that MSCs possess diverse immune regulatory capacities. Pre-cl

  17. Pluripotent Stem Cells for Schwann Cell Engineering

    NARCIS (Netherlands)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-01-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitu

  18. Induction of Functional Hair-Cell-Like Cells from Mouse Cochlear Multipotent Cells

    Directory of Open Access Journals (Sweden)

    Quanwen Liu

    2016-01-01

    Full Text Available In this paper, we developed a two-step-induction method of generating functional hair cells from inner ear multipotent cells. Multipotent cells from the inner ear were established and induced initially into progenitor cells committed to the inner ear cell lineage on the poly-L-lysine substratum. Subsequently, the committed progenitor cells were cultured on the mitotically inactivated chicken utricle stromal cells and induced into hair-cell-like cells containing characteristic stereocilia bundles. The hair-cell-like cells exhibited rapid permeation of FM1-43FX. The whole-cell patch-clamp technique was used to measure the membrane currents of cells differentiated for 7 days on chicken utricle stromal cells and analyze the biophysical properties of the hair-cell-like cells by recording membrane properties of cells. The results suggested that the hair-cell-like cells derived from inner ear multipotent cells were functional following differentiation in an enabling environment.

  19. Cell-ECM traction force modulates endogenous tension at cell-cell contacts

    National Research Council Canada - National Science Library

    Venkat Maruthamuthu; Benedikt Sabass; Ulrich S. Schwarz; Margaret L. Gardel; Shu Chien

    2011-01-01

    .... A direct relationship between the total cellular traction force on the ECM and the endogenous cell-cell force exists, indicating that the cell-cell tension is a constant fraction of the cell-ECM traction...

  20. Natural Killer Cell Memory.

    Science.gov (United States)

    O'Sullivan, Timothy E; Sun, Joseph C; Lanier, Lewis L

    2015-10-20

    Natural killer (NK) cells have historically been considered short-lived cytolytic cells that can rapidly respond against pathogens and tumors in an antigen-independent manner and then undergo cell death. Recently, however, NK cells have been shown to possess traits of adaptive immunity and can acquire immunological memory in a manner similar to that of T and B cells. In this review, we discuss evidence of NK cell memory and the mechanisms involved in the generation and survival of these innate lymphocytes. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Pluripotent stem cells for Schwann cell engineering.

    Science.gov (United States)

    Ma, Ming-San; Boddeke, Erik; Copray, Sjef

    2015-04-01

    Tissue engineering of Schwann cells (SCs) can serve a number of purposes, such as in vitro SC-related disease modeling, treatment of peripheral nerve diseases or peripheral nerve injury, and, potentially, treatment of CNS diseases. SCs can be generated from autologous stem cells in vitro by recapitulating the various stages of in vivo neural crest formation and SC differentiation. In this review, we survey the cellular and molecular mechanisms underlying these in vivo processes. We then focus on the current in vitro strategies for generating SCs from two sources of pluripotent stem cells, namely embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs). Different methods for SC engineering from ESCs and iPSCs are reviewed and suggestions are proposed for optimizing the existing protocols. Potential safety issues regarding the clinical application of iPSC-derived SCs are discussed as well. Lastly, we will address future aspects of SC engineering.

  2. Novel mechanism of diglyceride formation: 12-O-tetra-decanoyl-phorbol-13-acetate stimulates the cyclic breakdown and resynthesis of phosphatidylcholine

    Energy Technology Data Exchange (ETDEWEB)

    Daniel, L.W.; Waite, M.; Wykle, R.L.

    1986-05-01

    12-O-Tetradecanoyl-phorbol-13-acetate (TPA) treatment of Madin-Darby canine kidney (MDCK) cells resulted in an increased incorporation of /sup 32/P/sub i/ and (methyl-/sup 3/H)choline into choline-containing phosphoglycerides (PC). In pulse-chase experiments, TPA treatment caused an increased release of (methyl-/sup 3/H)choline from the PC fraction of prelabeled cells. When cells were prelabeled with (/sup 3/H)arachidonic acid and (/sup 14/C)palmitic acid, TPA treatment resulted in an increased synthesis of /sup 3/H- and /sup 14/C-diglycerides. Further studies were done to determine the relationship between PC breakdown and diglyceride synthesis. Cells were preincubated with ether-linked 1-O-(/sup 3/H)hexadecyl-2-lyso-sn-glycero-3-phosphocholine which was acylated to form 1-O-(/sup 3/H)hexadecyl-2-acyl-sn-glycero-3-phosphocholine. Subsequent treatment of these cells with TPA resulted in an increased synthesis of 1-O-(/sup 3/H)hexadecyl-2-acyl-sn-glycerol compared to that of cells not stimulated with TPA. These findings demonstrate that TPA stimulates PC turnover in MDCK cells and provides evidence for a novel mechanism of diglyceride formation by degradation of PC by a phospholipase C.

  3. The cell cycle as a brake for β-cell regeneration from embryonic stem cells.

    Science.gov (United States)

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-13

    The generation of insulin-producing β cells from stem cells in vitro provides a promising source of cells for cell transplantation therapy in diabetes. However, insulin-producing cells generated from human stem cells show deficiency in many functional characteristics compared with pancreatic β cells. Recent reports have shown molecular ties between the cell cycle and the differentiation mechanism of embryonic stem (ES) cells, assuming that cell fate decisions are controlled by the cell cycle machinery. Both β cells and ES cells possess unique cell cycle machinery yet with significant contrasts. In this review, we compare the cell cycle control mechanisms in both ES cells and β cells, and highlight the fundamental differences between pluripotent cells of embryonic origin and differentiated β cells. Through critical analysis of the differences of the cell cycle between these two cell types, we propose that the cell cycle of ES cells may act as a brake for β-cell regeneration. Based on these differences, we discuss the potential of modulating the cell cycle of ES cells for the large-scale generation of functionally mature β cells in vitro. Further understanding of the factors that modulate the ES cell cycle will lead to new approaches to enhance the production of functional mature insulin-producing cells, and yield a reliable system to generate bona fide β cells in vitro.

  4. Regulatory T cells and B cells: implication on autoimmune diseases

    OpenAIRE

    Wang, Ping; Zheng, Song Guo

    2013-01-01

    The regulatory T (Treg) cells play an important role in the maintenance of homeostasis and the prevention of autoimmune diseases. Although most studies are focusing on the role of Treg cells in T cells and T cells-mediated diseases, these cells also directly affect B cells and other non-T cells. This manuscript updates the role of Treg cells on the B cells and B cell-mediated diseases. In addition, the mechanisms whereby Treg cells suppress B cell responses have been discussed.

  5. Cell signaling review series

    Institute of Scientific and Technical Information of China (English)

    Aiming Lin; Zhenggang Liu

    2008-01-01

    @@ Signal transduction is pivotal for many, if not all, fundamental cellular functions including proliferation, differentiation, transformation and programmed cell death. Deregulation of cell signaling may result in certain types of cancers and other human diseases.

  6. Stem Cell Transplant

    Science.gov (United States)

    ... transplant is a procedure that infuses healthy blood stem cells into your body to replace your damaged or ... A bone marrow transplant is also called a stem cell transplant. A bone marrow transplant may be necessary ...

  7. Sickle Cell Information Center

    Science.gov (United States)

    ... Nature, Wash Post, SciAm, CNN - Google Custom Search Sickle Cell Anemia News -- ScienceDaily January 18, 1970 Read articles summarizing medical research on sickle-cell anemia. NYT, Nature, Wash Post, SciAm, CNN - Google Custom ...

  8. NIA Aging Cell Repository

    Data.gov (United States)

    Federal Laboratory Consortium — To facilitate aging research on cells in culture, the NIA provides support for the NIA Aging Cell Repository, located at the Coriell Institute for Medical Research...

  9. Stem Cell Basics

    Science.gov (United States)

    ... why are they important? Stem cells have the remarkable potential to develop into many different cell types ... of Health, U.S. Department of Health and Human Services, 2016 [cited October 9, 2017 ] Available at < //stemcells. ...

  10. Sickle Cell Disease

    Science.gov (United States)

    ... About Us Overview of CDC’s work. Advancements in Sickle Cell Disease New supplement from the American Journal of Preventive Medicine describes the state of sickle cell disease related care in the United States. Read Supplement ...

  11. FUEL CELL ELECTRODE MATERIALS

    Science.gov (United States)

    FUEL CELL ELECTRODE MATERIALS. RAW MATERIAL SELECTION INFLUENCES POLARIZATION BUT IS NOT A SINGLE CONTROLLING FACTOR. AVAILABLE...DATA INDICATES THAT AN INTERRELATIONSHIP OF POROSITY, AVERAGE PORE VOLUME, AND PERMEABILITY CONTRIBUTES TO ELECTRODE FUEL CELL BEHAVIOR.

  12. Engineering Stem Cell Organoids

    National Research Council Canada - National Science Library

    Yin, Xiaolei; Mead, Benjamin E; Safaee, Helia; Langer, Robert; Karp, Jeffrey M; Levy, Oren

    2016-01-01

    .... Herein, we discuss basic approaches to generate stem cell-based organoids, their advantages and limitations, and how bioengineering strategies can be used to steer the cell composition and their 3D...

  13. Giant Cell Arteritis

    Science.gov (United States)

    Giant cell arteritis is a disorder that causes inflammation of your arteries, usually in the scalp, neck, and arms. ... arteries, which keeps blood from flowing well. Giant cell arteritis often occurs with another disorder called polymyalgia ...

  14. Odontogenic ghost cell tumour with clear cell components: clear cell odontogenic ghost cell tumour?

    Science.gov (United States)

    Yoon, Jung Hoon; Ahn, Sang Gun; Kim, Su Gwan; Kim, Jin

    2004-07-01

    A case of odontogenic ghost cell tumour (OGCT) with clear cell components was encountered in the mandible of a 63-year-old man. The tumour revealed ameloblastomatous-type epithelial components accompanied by clusters of ghost cells and dentinoid juxtaposed to the odontogenic epithelium. In addition, some areas of the tumour tissue showed sheets and islands of clear, glycogen containing epithelial cells, which were separated by a thin fibrous connective tissue stroma. Both ameloblastic and clear cells exhibited positive immunoreactivities for cytokeratin 19 and AE1/3. It is not known whether this tumour represents a clear cell change of a pre-existing OGCT or a separate and distinct neoplasm derived de novo from the odontogenic epithelium. This tumour was given the term 'clear cell OGCT' because it captures the clear cell components, which is one of the most prominent distinguishing features of the tumour.

  15. Sickle Cell Disease Quiz

    Science.gov (United States)

    ... Websites About Us Information For... Media Policy Makers Sickle Cell Disease Quiz Language: English Español (Spanish) Recommend on ... 1. True or False: Only African Americans get sickle cell disease. A True B False 2. True or ...

  16. Sickle cell anemia.

    OpenAIRE

    ŘÍHOVÁ, Tereza

    2013-01-01

    This thesis is about the disease called sickle cell anemia, or drepanocytosis. In this thesis is described the history of the disease, pathophysiology, laboratory features, various clinical features, diferencial diagnosis, quality of life in sickle cell anemia and therapy.

  17. Cell-SELEX Technology

    Science.gov (United States)

    2012-01-01

    Abstract Aptamers are molecules identified from large combinatorial nucleic acid libraries by their high affinity to target molecules. Due to a variety of desired properties, aptamers are attractive alternatives to antibodies in molecular biology and medical applications. Aptamers are identified through an iterative selection–amplification process known as systematic evolution of ligands by exponential enrichment (SELEX). Although SELEX is typically carried out using purified target molecules, whole live cells are also employable as selection targets. This technology, Cell-SELEX, has several advantages. For example, generated aptamers are functional with a native conformation of the target molecule on live cells, and thus, cell surface transmembrane proteins would be targets even when their purifications in native conformations are difficult. In addition, cell-specific aptamers can be obtained without any knowledge about cell surface molecules on the target cells. Here, I review the progress of Cell-SELEX technology and discuss advantages of the technology. PMID:23515081

  18. White Blood Cell Count

    Science.gov (United States)

    ... limited. Home Visit Global Sites Search Help? White Blood Cell Count Share this page: Was this page helpful? ... Count; Leukocyte Count; White Count Formal name: White Blood Cell Count Related tests: Complete Blood Count , Blood Smear , ...

  19. Mast cell activation disease

    African Journals Online (AJOL)

    EL-HAKIM

    only IgE dependent allergic diseases but also play a ... Mast cells are tissue fixed effector cells of allergic ..... alleviated high intensity symptoms of MCAD.29 ... Osteoporosis, osteolysis, bone pain: biphosphonates (vitamin D plus calcium.

  20. Cell phone explosion.

    Science.gov (United States)

    Atreya, Alok; Kanchan, Tanuj; Nepal, Samata; Pandey, Bhuwan Raj

    2016-03-01

    Cell phone explosions and resultant burn injuries are rarely reported in the scientific literature. We report a case of cell phone explosion that occurred when a young male was listening to music while the mobile was plugged in for charging.

  1. Red blood cell production

    Science.gov (United States)

    ... to one part of the body or another. Red blood cells are an important element of blood. Their job ... is carried to and eliminated by the lungs. Red blood cells are formed in the red bone marrow of ...

  2. Mast cell proteoglycans.

    Science.gov (United States)

    Rönnberg, Elin; Melo, Fabio R; Pejler, Gunnar

    2012-12-01

    Mast cells are versatile effector cells of the immune system, contributing to both innate and adaptive immunity toward pathogens but also having profound detrimental activities in the context of inflammatory disease. A hallmark morphological feature of mast cells is their large content of cytoplasmic secretory granules, filled with numerous secretory compounds, including highly negatively charged heparin or chondroitin sulfate proteoglycans of serglycin type. These anionic proteoglycans provide the basis for the strong metachromatic staining properties of mast cells seen when applying various cationic dyes. Functionally, the mast cell proteoglycans have been shown to have an essential role in promoting the storage of other granule-contained compounds, including bioactive monoamines and different mast cell-specific proteases. Moreover, granule proteoglycans have been shown to regulate the enzymatic activities of mast cell proteases and to promote apoptosis. Here, the current knowledge of mast cell proteoglycans is reviewed.

  3. Diagram of Cell to Cell Communication

    Science.gov (United States)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  4. Diagram of Cell to Cell Communication

    Science.gov (United States)

    2002-01-01

    Diagram depicts the importance of cell-cell communication as central to the understanding of cancer growth and progression, the focus of the NASA bioreactor demonstration system (BDS-05) investigation. Microgravity studies will allow us to unravel the signaling and communication between these cells with the host and potential development of therapies for the treatment of cancer metastasis. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators. Credit: Emory University.

  5. Increased voltage photovoltaic cell

    Science.gov (United States)

    Ross, B.; Bickler, D. B.; Gallagher, B. D. (Inventor)

    1985-01-01

    A photovoltaic cell, such as a solar cell, is provided which has a higher output voltage than prior cells. The improved cell includes a substrate of doped silicon, a first layer of silicon disposed on the substrate and having opposite doping, and a second layer of silicon carbide disposed on the first layer. The silicon carbide preferably has the same type of doping as the first layer.

  6. Storage of cell lines.

    Science.gov (United States)

    Parker, Katharine A

    2011-01-01

    The successful storage of cell lines depends upon many factors, including the condition of the cells to be frozen and the experience of the operator. Attempting to freeze down unhealthy, contaminated or poorly labelled cells can have huge implications for a research laboratory. This chapter outlines the importance of good record keeping, vigilant monitoring, aseptic technique, and high-quality reagents in the successful storage and downstream propagation of cell lines.

  7. Skeletal (stromal) stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem M; Kermani, Abbas Jafari; Zaher, Walid

    2015-01-01

    Skeletal (marrow stromal) stem cells (BMSCs) are a group of multipotent cells that reside in the bone marrow stroma and can differentiate into osteoblasts, chondrocytes and adipocytes. Studying signaling pathways that regulate BMSC differentiation into osteoblastic cells is a strategy....../preadipocyte factor 1 (Dlk1/Pref-1), the Wnt co-receptor Lrp5 and intracellular kinases. This article is part of a Special Issue entitled: Stem Cells and Bone....

  8. STEM CELLS AND PROTEOMICS

    Institute of Scientific and Technical Information of China (English)

    ZHOU Yong-ming; GUO Tian-nan; HUANG Shi-ang

    2006-01-01

    The distinctive features of proteomics are large-scale and high throughput. The key techniques of proteomics are two-dimensional gel electrophoresis, mass spectrometry and bioinformatics. Stem cell can differentiate into all kinds of cells, tissues and organs. There are many proteins and cytokines involved in the process of differentiation. Applying proteomics techniques to the research of the complex process of stem cell differentiation is of great importance to study the mechanism and applications of stem cell differentiation.

  9. Fish stem cell cultures.

    Science.gov (United States)

    Hong, Ni; Li, Zhendong; Hong, Yunhan

    2011-04-13

    Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES) cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on "Fish Stem Cells and Nuclear Transfer", we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  10. Kidney Cell Electrophoresis

    Science.gov (United States)

    Todd, P.

    1985-01-01

    Materials and procedures for microgravity electrophoresis of living human embryonic kidney cells were evaluated, ground support in the form of analytical cell electrophoresis and flow cytometry was provided and cells returned from space flight were analyzed. Preflight culture media, electrophoresis buffer, fraction collection media, temperature profiles, and urokinase assay procedures were tested prior to flight. Electrophoretic mobility distributions of aliquots of the cell population to be fractionated in flight were obtained. The protocol established and utilized is given.

  11. Fish Stem Cell Cultures

    Directory of Open Access Journals (Sweden)

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    Full Text Available Stem cells have the potential for self-renewal and differentiation. First stem cell cultures were derived 30 years ago from early developing mouse embryos. These are pluripotent embryonic stem (ES cells. Efforts towards ES cell derivation have been attempted in other mammalian and non-mammalian species. Work with stem cell culture in fish started 20 years ago. Laboratory fish species, in particular zebrafish and medaka, have been the focus of research towards stem cell cultures. Medaka is the second organism that generated ES cells and the first that gave rise to a spermatogonial stem cell line capable of test-tube sperm production. Most recently, the first haploid stem cells capable of producing whole animals have also been generated from medaka. ES-like cells have been reported also in zebrafish and several marine species. Attempts for germline transmission of ES cell cultures and gene targeting have been reported in zebrafish. Recent years have witnessed the progress in markers and procedures for ES cell characterization. These include the identification of fish homologs/paralogs of mammalian pluripotency genes and parameters for optimal chimera formation. In addition, fish germ cell cultures and transplantation have attracted considerable interest for germline transmission and surrogate production. Haploid ES cell nuclear transfer has proven in medaka the feasibility of semi-cloning as a novel assisted reproductive technology. In this special issue on “Fish Stem Cells and Nuclear Transfer”, we will focus our review on medaka to illustrate the current status and perspective of fish stem cells in research and application. We will also mention semi-cloning as a new development to conventional nuclear transfer.

  12. Stem cell heterogeneity revealed

    DEFF Research Database (Denmark)

    Andersen, Marianne S; Jensen, Kim B

    2016-01-01

    The skin forms a protective, water-impermeable barrier consisting of heavily crosslinked epithelial cells. However, the specific role of stem cells in sustaining this barrier remains a contentious issue. A detailed analysis of the interfollicular epidermis now proposes a model for how a composite...... of cells with different properties are involved in its maintenance....

  13. SYNOVIAL CELL SARCOMA

    Directory of Open Access Journals (Sweden)

    M. Farzan

    1997-06-01

    Full Text Available Ten cases of synovial cell sarcoma are reported. The youngest patient was a 2'A years old boy with synovial cell sarcoma of the knee and the oldest one was a man with synovial cell sarcoma of the elbow.

  14. Embryonic Stem Cell Markers

    Directory of Open Access Journals (Sweden)

    Lan Ma

    2012-05-01

    Full Text Available Embryonic stem cell (ESC markers are molecules specifically expressed in ES cells. Understanding of the functions of these markers is critical for characterization and elucidation for the mechanism of ESC pluripotent maintenance and self-renewal, therefore helping to accelerate the clinical application of ES cells. Unfortunately, different cell types can share single or sometimes multiple markers; thus the main obstacle in the clinical application of ESC is to purify ES cells from other types of cells, especially tumor cells. Currently, the marker-based flow cytometry (FCM technique and magnetic cell sorting (MACS are the most effective cell isolating methods, and a detailed maker list will help to initially identify, as well as isolate ESCs using these methods. In the current review, we discuss a wide range of cell surface and generic molecular markers that are indicative of the undifferentiated ESCs. Other types of molecules, such as lectins and peptides, which bind to ESC via affinity and specificity, are also summarized. In addition, we review several markers that overlap with tumor stem cells (TSCs, which suggest that uncertainty still exists regarding the benefits of using these markers alone or in various combinations when identifying and isolating cells.

  15. Advanced Cell Technology, Inc.

    Science.gov (United States)

    Caldwell, William M

    2007-03-01

    Advanced Cell Technology, Inc. (OTCBB: ACTC) is a biotechnology company applying novel human embryonic stem cell technologies in the emerging field of regenerative medicine. We believe that regenerative medicine has the potential to revolutionize the field by enabling scientists to produce human cells of any kind for use in a wide array of therapies.

  16. Nanostructured Organic Solar Cells

    DEFF Research Database (Denmark)

    Radziwon, Michal Jędrzej; Rubahn, Horst-Günter; Madsen, Morten

    Recent forecasts for alternative energy generation predict emerging importance of supporting state of art photovoltaic solar cells with their organic equivalents. Despite their significantly lower efficiency, number of application niches are suitable for organic solar cells. This work reveals...... the principles of bulk heterojunction organic solar cells fabrication as well as summarises major differences in physics of their operation....

  17. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  18. Photoelectrochemical Solar Cells.

    Science.gov (United States)

    McDevitt, John T.

    1984-01-01

    This introduction to photoelectrochemical (PEC) cells reviews topics pertaining to solar energy conversion and demonstrates the ease with which a working PEC cell can be prepared with n-type silicon as the photoanode and a platinum counter electrode (both immersed in ethanolic ferrocene/ferricenium solutions). Experiments using the cell are…

  19. Adventures with Cell Phones

    Science.gov (United States)

    Kolb, Liz

    2011-01-01

    Teachers are finding creative ways to turn the basic cell phone from a digital distraction into a versatile learning tool. In this article, the author explains why cell phones are important in learning and suggests rather than banning them that they be integrated into learning. She presents activities that can be done on a basic cell phone with a…

  20. Cell phones and cancer

    Science.gov (United States)

    Cancer and cell phones; Do cell phones cause cancer? ... Several major studies show no link between cell phones and cancer at this time. However, since the information available is based on short-term studies, the impact of many years of ...

  1. Mammalian Cell Culture Simplified.

    Science.gov (United States)

    Moss, Robert; Solomon, Sondra

    1991-01-01

    A tissue culture experiment that does not require elaborate equipment and that can be used to teach sterile technique, the principles of animal cell line maintenance, and the concept of cell growth curves is described. The differences between cancerous and normal cells can be highlighted. The procedure is included. (KR)

  2. Dazlin' pluripotent stem cells

    NARCIS (Netherlands)

    Welling, M.A.

    2014-01-01

    Pluripotent embryonic stem cells (ESCs) can be isolated from the inner cell mass (ICM) of blastocyst embryos and differentiate into all three germ layers in vitro. However, despite their similar origin, mouse embryonic stem cells represent a more naïve ICM-like pluripotent state whereas human embryo

  3. Cell Culture Made Easy.

    Science.gov (United States)

    Dye, Frank J.

    1985-01-01

    Outlines steps to generate cell samples for observation and experimentation. The procedures (which use ordinary laboratory equipment) will establish a short-term primary culture of normal mammalian cells. Information on culture vessels and cell division and a list of questions to generate student interest and involvement in the topics are…

  4. Solar Photovoltaic Cells.

    Science.gov (United States)

    Mickey, Charles D.

    1981-01-01

    Reviews information on solar radiation as an energy source. Discusses these topics: the key photovoltaic material; the bank theory of solids; conductors, semiconductors, and insulators; impurity semiconductors; solid-state photovoltaic cell operation; limitations on solar cell efficiency; silicon solar cells; cadmium sulfide/copper (I) sulfide…

  5. Fuel cell catalyst degradation

    DEFF Research Database (Denmark)

    Arenz, Matthias; Zana, Alessandro

    2016-01-01

    Fuel cells are an important piece in our quest for a sustainable energy supply. Although there are several different types of fuel cells, the by far most popular is the proton exchange membrane fuel cell (PEMFC). Among its many favorable properties are a short start up time and a high power density...

  6. Aneuploidy in stem cells

    NARCIS (Netherlands)

    Garcia-Martinez, Jorge; Bakker, Bjorn; Schukken, Klaske M; Simon, Judith E; Foijer, Floris

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells (IPSCs) from somatic cells has brought this promise steps closer to real

  7. Border cell release

    DEFF Research Database (Denmark)

    Mravec, Jozef

    2017-01-01

    Plant border cells are specialised cells derived from the root cap with roles in the biomechanics of root growth and in forming a barrier against pathogens. The mechanism of highly localised cell separation which is essential for their release to the environment is little understood. Here I present...

  8. Battery cell module

    Energy Technology Data Exchange (ETDEWEB)

    Shambaugh, J.S.

    1981-11-23

    A modular lithium battery having a plurality of cells, having electrical connecting means connecting the cells to output terminals, and venting means for releasing discharge byproducts to a chemical scrubber is disclosed. Stainless steel cell casings are potted in an aluminum modular case with syntactic foam and epoxy. The wall thickness resulting is about 0.5 inches.

  9. Mouse Leydig Tumor Cells

    Directory of Open Access Journals (Sweden)

    Bo-Syong Pan

    2011-01-01

    Full Text Available Cordycepin is a natural pure compound extracted from Cordyceps sinensis (CS. We have demonstrated that CS stimulates steroidogenesis in primary mouse Leydig cell and activates apoptosis in MA-10 mouse Leydig tumor cells. It is highly possible that cordycepin is the main component in CS modulating Leydig cell functions. Thus, our aim was to investigate the steroidogenic and apoptotic effects with potential mechanism of cordycepin on MA-10 mouse Leydig tumor cells. Results showed that cordycepin significantly stimulated progesterone production in dose- and time-dependent manners. Adenosine receptor (AR subtype agonists were further used to treat MA-10 cells, showing that A1, A 2A , A 2B , and A3, AR agonists could stimulate progesterone production. However, StAR promoter activity and protein expression remained of no difference among all cordycepin treatments, suggesting that cordycepin might activate AR, but not stimulated StAR protein to regulate MA-10 cell steroidogenesis. Meanwhile, cordycepin could also induce apoptotic cell death in MA-10 cells. Moreover, four AR subtype agonists induced cell death in a dose-dependent manner, and four AR subtype antagonists could all rescue cell death under cordycepin treatment in MA-10 cells. In conclusion, cordycepin could activate adenosine subtype receptors and simultaneously induce steroidogenesis and apoptosis in MA-10 mouse Leydig tumor cells.

  10. Molecular Mechanisms of HTLV-1 Cell-to-Cell Transmission

    Directory of Open Access Journals (Sweden)

    Christine Gross

    2016-03-01

    Full Text Available The tumorvirus human T-cell lymphotropic virus type 1 (HTLV-1, a member of the delta-retrovirus family, is transmitted via cell-containing body fluids such as blood products, semen, and breast milk. In vivo, HTLV-1 preferentially infects CD4+ T-cells, and to a lesser extent, CD8+ T-cells, dendritic cells, and monocytes. Efficient infection of CD4+ T-cells requires cell-cell contacts while cell-free virus transmission is inefficient. Two types of cell-cell contacts have been described to be critical for HTLV-1 transmission, tight junctions and cellular conduits. Further, two non-exclusive mechanisms of virus transmission at cell-cell contacts have been proposed: (1 polarized budding of HTLV-1 into synaptic clefts; and (2 cell surface transfer of viral biofilms at virological synapses. In contrast to CD4+ T-cells, dendritic cells can be infected cell-free and, to a greater extent, via viral biofilms in vitro. Cell-to-cell transmission of HTLV-1 requires a coordinated action of steps in the virus infectious cycle with events in the cell-cell adhesion process; therefore, virus propagation from cell-to-cell depends on specific interactions between cellular and viral proteins. Here, we review the molecular mechanisms of HTLV-1 transmission with a focus on the HTLV-1-encoded proteins Tax and p8, their impact on host cell factors mediating cell-cell contacts, cytoskeletal remodeling, and thus, virus propagation.

  11. Phosphoinositides in barley aleurone layers and gibberellic acid-induced changes in metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Murthy, P.P.N.; Renders, J.M.; Keranen, L.M. (Michigan Technological Univ., Houghton (USA))

    1989-12-01

    Phospholipids of barley (Hordeum vulgare L. cv Himalaya) aleurone layers were labeled with myo-(2-{sup 3}H)inositol or ({sup 32}Pi), extracted, and analyzed by physical (chromatography) and chemical (deacylation) techniques. Three phospholipids were found to incorporate both myo-(2-{sup 3}H)inositol and ({sup 32}Pi)-phosphatidylinositol, phosphatidylinositol-monophosphate, and phosphatidylinositol-bisphosphate. Stimulation of ({sup 3}H)inositol prelabeled aleurone layers with GA{sub 3} showed enhanced incorporation of label into phosphatidylinositol within 30 seconds and subsequent rapid breakdown. Stimulation of phosphatidylinositol labeling observed in these studies is the earliest response of aleurone cells to gibberellic acid reported.

  12. Cell-ECM traction force modulates endogenous tension at cell-cell contacts.

    Science.gov (United States)

    Maruthamuthu, Venkat; Sabass, Benedikt; Schwarz, Ulrich S; Gardel, Margaret L

    2011-03-22

    Cells in tissues are mechanically coupled both to the ECM and neighboring cells, but the coordination and interdependency of forces sustained at cell-ECM and cell-cell adhesions are unknown. In this paper, we demonstrate that the endogenous force sustained at the cell-cell contact between a pair of epithelial cells is approximately 100 nN, directed perpendicular to the cell-cell interface and concentrated at the contact edges. This force is stably maintained over time despite significant fluctuations in cell-cell contact length and cell morphology. A direct relationship between the total cellular traction force on the ECM and the endogenous cell-cell force exists, indicating that the cell-cell tension is a constant fraction of the cell-ECM traction. Thus, modulation of ECM properties that impact cell-ECM traction alters cell-cell tension. Finally, we show in a minimal model of a tissue that all cells experience similar forces from the surrounding microenvironment, despite differences in the extent of cell-ECM and cell-cell adhesion. This interdependence of cell-cell and cell-ECM forces has significant implications for the maintenance of the mechanical integrity of tissues, mechanotransduction, and tumor mechanobiology.

  13. Mechanics rules cell biology

    Directory of Open Access Journals (Sweden)

    Wang James HC

    2010-07-01

    Full Text Available Abstract Cells in the musculoskeletal system are subjected to various mechanical forces in vivo. Years of research have shown that these mechanical forces, including tension and compression, greatly influence various cellular functions such as gene expression, cell proliferation and differentiation, and secretion of matrix proteins. Cells also use mechanotransduction mechanisms to convert mechanical signals into a cascade of cellular and molecular events. This mini-review provides an overview of cell mechanobiology to highlight the notion that mechanics, mainly in the form of mechanical forces, dictates cell behaviors in terms of both cellular mechanobiological responses and mechanotransduction.

  14. Transparent ultraviolet photovoltaic cells.

    Science.gov (United States)

    Yang, Xun; Shan, Chong-Xin; Lu, Ying-Jie; Xie, Xiu-Hua; Li, Bing-Hui; Wang, Shuang-Peng; Jiang, Ming-Ming; Shen, De-Zhen

    2016-02-15

    Photovoltaic cells have been fabricated from p-GaN/MgO/n-ZnO structures. The photovoltaic cells are transparent to visible light and can transform ultraviolet irradiation into electrical signals. The efficiency of the photovoltaic cells is 0.025% under simulated AM 1.5 illumination conditions, while it can reach 0.46% under UV illumination. By connecting several such photovoltaic cells in a series, light-emitting devices can be lighting. The photovoltaic cells reported in this Letter may promise the applications in glass of buildings to prevent UV irradiation and produce power for household appliances in the future.

  15. Human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem; Kassem, Moustapha

    2008-01-01

    Mesenchymal stem cells (MSC) are a group of clonogenic cells present among the bone marrow stroma and capable of multilineage differentiation into mesoderm-type cells such as osteoblasts, adipocytes and chondrocytes. Due to their ease of isolation and their differentiation potential, MSC are being...... introduced into clinical medicine in variety of applications and through different ways of administration. Here, we discuss approaches for isolation, characterization and directing differentiation of human mesenchymal stem cells (hMSC). An update of the current clinical use of the cells is also provided....

  16. Dental pulp stem cells

    DEFF Research Database (Denmark)

    Ashri, N. Y.; Ajlan, S. A.; Aldahmash, Abdullah M.

    2015-01-01

    Inflammatory periodontal disease is a major cause of loss of tooth-supporting structures. Novel approaches for regeneration of periodontal apparatus is an area of intensive research. Periodontal tissue engineering implies the use of appropriate regenerative cells, delivered through a suitable...... scaffold, and guided through signaling molecules. Dental pulp stem cells have been used in an increasing number of studies in dental tissue engineering. Those cells show mesenchymal (stromal) stem cell-like properties including self-renewal and multilineage differentiation potentials, aside from...... an updated review on dental pulp stem cells and their applications in periodontal regeneration, in combination with different scaffolds and growth factors....

  17. New cell sources for T cell engineering and adoptive immunotherapy

    National Research Council Canada - National Science Library

    Themeli, Maria; Rivière, Isabelle; Sadelain, Michel

    2015-01-01

    .... Here we review emerging T cell engineering approaches that utilize alternative T cell sources, which include virus-specific or T cell receptor-less allogeneic T cells, expanded lymphoid progenitors...

  18. Fuel Cell/Electrochemical Cell Voltage Monitor

    Science.gov (United States)

    Vasquez, Arturo

    2012-01-01

    A concept has been developed for a new fuel cell individual-cell-voltage monitor that can be directly connected to a multi-cell fuel cell stack for direct substack power provisioning. It can also provide voltage isolation for applications in high-voltage fuel cell stacks. The technology consists of basic modules, each with an 8- to 16-cell input electrical measurement connection port. For each basic module, a power input connection would be provided for direct connection to a sub-stack of fuel cells in series within the larger stack. This power connection would allow for module power to be available in the range of 9-15 volts DC. The relatively low voltage differences that the module would encounter from the input electrical measurement connection port, coupled with the fact that the module's operating power is supplied by the same substack voltage input (and so will be at similar voltage), provides for elimination of high-commonmode voltage issues within each module. Within each module, there would be options for analog-to-digital conversion and data transfer schemes. Each module would also include a data-output/communication port. Each of these ports would be required to be either non-electrical (e.g., optically isolated) or electrically isolated. This is necessary to account for the fact that the plurality of modules attached to the stack will normally be at a range of voltages approaching the full range of the fuel cell stack operating voltages. A communications/ data bus could interface with the several basic modules. Options have been identified for command inputs from the spacecraft vehicle controller, and for output-status/data feeds to the vehicle.

  19. Internalization of NK cells into tumor cells requires ezrin and leads to programmed cell-in-cell death

    Institute of Scientific and Technical Information of China (English)

    Shan Wang; Zhen Guo; Peng Xia; Tingting Liu; Jufang Wang; Shan Li; Lihua Sun; Jianxin Lu; Qian Wen; Mingqian Zhou; Li Ma; Xia Ding; Xiaoning Wang; Xuebiao Yao

    2009-01-01

    Cytotoxic lymphocytes are key players in the orchestration of immune response and elimination of defective cells. We have previously reported that natural killer (NK) cells enter target tumor cells, leading to either target cell death or self-destruction within tumor cells. However, it has remained elusive as to the fate of NK cells after internaliza-tion and whether the heterotypic cell-in-cell process is different from that of the homotypic cell-in-cell event recently named entosis. Here, we show that NK cells undergo a cell-in-cell process with the ultimate fate of apoptosis within tumor cells and reveal that the internalization process requires the actin cytoskeletal regulator, ezrin. To visualize how NK cells enter into tumor cells, we carried out real-time dual color imaging analyses of NK cell internalization into tumor cells. Surprisingly, most NK cells commit to programmed cell death after their entry into tumor cells, which is distinctively different from entosis observed in the homotypic cell-in-cell process. The apoptotic cell death of the internalized NK cells was evident by activation of caspase 3 and DNA fragmentation. Furthermore, NK cell death after internalization is attenuated by the caspase inhibitor, Z-VAD-FMK, confirming apoptosis as the mode of NK cell death within tumor cells. To determine protein factors essential for the entry of NK cells into tumor cells, we car-ried out siRNA-based knockdown analysis and discovered a critical role of ezrin in NK cell internalization. Impor-tantly, PKA-mediated phosphorylation of ezrin promotes the NK cell internalization process. Our findings suggest a novel regulatory mechanism by which ezrin governs NK cell internalization into tumor cells.

  20. Islet cell development.

    Science.gov (United States)

    Rojas, Anabel; Khoo, Adrian; Tejedo, Juan R; Bedoya, Francisco J; Soria, Bernat; Martín, Franz

    2010-01-01

    Over the last years, there has been great success in driving stem cells toward insulin-expressing cells. However, the protocols developed to date have some limitations, such as low reliability and low insulin production. The most successful protocols used for generation of insulin-producing cells from stem cells mimic in vitro pancreatic organogenesis by directing the stem cells through stages that resemble several pancreatic developmental stages. Islet cell fate is coordinated by a complex network of inductive signals and regulatory transcription factors that, in a combinatorial way, determine pancreatic organ specification, differentiation, growth, and lineage. Together, these signals and factors direct the progression from multipotent progenitor cells to mature pancreatic cells. Later in development and adult life, several of these factors also contribute to maintain the differentiated phenotype of islet cells. A detailed understanding of the processes that operate in the pancreas during embryogenesis will help us to develop a suitable source of cells for diabetes therapy. In this chapter, we will discuss the main transcription factors involved in pancreas specification and beta-cell formation.

  1. Cell biology. Metabolic control of cell death.

    Science.gov (United States)

    Green, Douglas R; Galluzzi, Lorenzo; Kroemer, Guido

    2014-09-19

    Beyond their contribution to basic metabolism, the major cellular organelles, in particular mitochondria, can determine whether cells respond to stress in an adaptive or suicidal manner. Thus, mitochondria can continuously adapt their shape to changing bioenergetic demands as they are subjected to quality control by autophagy, or they can undergo a lethal permeabilization process that initiates apoptosis. Along similar lines, multiple proteins involved in metabolic circuitries, including oxidative phosphorylation and transport of metabolites across membranes, may participate in the regulated or catastrophic dismantling of organelles. Many factors that were initially characterized as cell death regulators are now known to physically or functionally interact with metabolic enzymes. Thus, several metabolic cues regulate the propensity of cells to activate self-destructive programs, in part by acting on nutrient sensors. This suggests the existence of "metabolic checkpoints" that dictate cell fate in response to metabolic fluctuations. Here, we discuss recent insights into the intersection between metabolism and cell death regulation that have major implications for the comprehension and manipulation of unwarranted cell loss.

  2. Cell viability assays: introduction.

    Science.gov (United States)

    Stoddart, Martin J

    2011-01-01

    The measurement of cell viability plays a fundamental role in all forms of cell culture. Sometimes it is the main purpose of the experiment, such as in toxicity assays. Alternatively, cell viability can be used to -correlate cell behaviour to cell number, providing a more accurate picture of, for example, anabolic -activity. There are wide arrays of cell viability methods which range from the most routine trypan blue dye exclusion assay to highly complex analysis of individual cells, such as using RAMAN microscopy. The cost, speed, and complexity of equipment required will all play a role in determining the assay used. This chapter aims to provide an overview of many of the assays available today.

  3. Cell Factory Engineering.

    Science.gov (United States)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-03-22

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta-review provides general strategy guides for the broad range of applications of rational engineering of cell factories.

  4. Mammary gland stem cells

    DEFF Research Database (Denmark)

    Fridriksdottir, Agla J R; Petersen, Ole W; Rønnov-Jessen, Lone

    2011-01-01

    Distinct subsets of cells, including cells with stem cell-like properties, have been proposed to exist in normal human breast epithelium and breast carcinomas. The cellular origins of epithelial cells contributing to gland development, tissue homeostasis and cancer are, however, still poorly...... understood. The mouse is a widely used model of mammary gland development, both directly by studying the mouse mammary epithelial cells themselves and indirectly, by studying development, morphogenesis, differentiation and carcinogenesis of xenotransplanted human breast epithelium in vivo. While in early...... studies, human or mouse epithelium was implanted as fragments into the mouse gland, more recent technical progress has allowed the self-renewal capacity and differentiation potential of distinct cell populations or even individual cells to be interrogated. Here, we review and discuss similarities...

  5. Enteroendocrine cell types revisited

    DEFF Research Database (Denmark)

    Engelstoft, Maja S; Egerod, Kristoffer Lihme; Lund, Mari L

    2013-01-01

    The GI-tract is profoundly involved in the control of metabolism through peptide hormones secreted from enteroendocrine cells scattered throughout the gut mucosa. A large number of recently generated transgenic reporter mice have allowed for direct characterization of biochemical and cell...... biological properties of these previously highly elusive enteroendocrine cells. In particular the surprisingly broad co-expression of six functionally related hormones in the intestinal enteroendocrine cells indicates that it should be possible to control not only the hormone secretion but also the type...... and number of enteroendocrine cells. However, this will require a more deep understanding of the factors controlling differentiation, gene expression and specification of the enteroendocrine cells during their weekly renewal from progenitor cells in the crypts of the mucosa....

  6. Peripheral giant cell granuloma

    Directory of Open Access Journals (Sweden)

    Padam Narayan Tandon

    2012-01-01

    Full Text Available Peripheral giant cell granuloma or the so-called "giant cell epulis" is the most common oral giant cell lesion. It normally presents as a soft tissue purplish-red nodule consisting of multinucleated giant cells in a background of mononuclear stromal cells and extravasated red blood cells. This lesion probably does not represent a true neoplasm, but rather may be reactive in nature, believed to be stimulated by local irritation or trauma, but the cause is not certainly known. This article reports a case of peripheral giant cell granuloma arising at the maxillary anterior region in a 22-year-old female patient. The lesion was completely excised to the periosteum level and there is no residual or recurrent swelling or bony defect apparent in the area of biopsy after a follow-up period of 6 months.

  7. Cell and Tissue Engineering

    CERN Document Server

    2012-01-01

    Cell and Tissue Engineering” introduces the principles and new approaches in cell and tissue engineering. It includes both the fundamentals and the current trends in cell and tissue engineering, in a way useful both to a novice and an expert in the field. The book is composed of 13 chapters all of which are written by the leading experts. It is organized to gradually assemble an insight in cell and tissue function starting form a molecular nano-level, extending to a cellular micro-level and finishing at the tissue macro-level. In specific, biological, physiological, biophysical, biochemical, medical, and engineering aspects are covered from the standpoint of the development of functional substitutes of biological tissues for potential clinical use. Topics in the area of cell engineering include cell membrane biophysics, structure and function of the cytoskeleton, cell-extracellular matrix interactions, and mechanotransduction. In the area of tissue engineering the focus is on the in vitro cultivation of ...

  8. Human regulatory B cells control the TFH cell response.

    Science.gov (United States)

    Achour, Achouak; Simon, Quentin; Mohr, Audrey; Séité, Jean-François; Youinou, Pierre; Bendaoud, Boutahar; Ghedira, Ibtissem; Pers, Jacques-Olivier; Jamin, Christophe

    2017-07-01

    Follicular helper T (TFH) cells support terminal B-cell differentiation. Human regulatory B (Breg) cells modulate cellular responses, but their control of TFH cell-dependent humoral immune responses is unknown. We sought to assess the role of Breg cells on TFH cell development and function. Human T cells were polyclonally stimulated in the presence of IL-12 and IL-21 to generate TFH cells. They were cocultured with B cells to induce their terminal differentiation. Breg cells were included in these cultures, and their effects were evaluated by using flow cytometry and ELISA. B-cell lymphoma 6, IL-21, inducible costimulator, CXCR5, and programmed cell death protein 1 (PD-1) expressions increased on stimulated human T cells, characterizing TFH cell maturation. In cocultures they differentiated B cells into CD138(+) plasma and IgD(-)CD27(+) memory cells and triggered immunoglobulin secretions. Breg cells obtained by Toll-like receptor 9 and CD40 activation of B cells prevented TFH cell development. Added to TFH cell and B-cell cocultures, they inhibited B-cell differentiation, impeded immunoglobulin secretions, and expanded Foxp3(+)CXCR5(+)PD-1(+) follicular regulatory T cells. Breg cells modulated IL-21 receptor expressions on TFH cells and B cells, and their suppressive activities involved CD40, CD80, CD86, and intercellular adhesion molecule interactions and required production of IL-10 and TGF-β. Human Breg cells control TFH cell maturation, expand follicular regulatory T cells, and inhibit the TFH cell-mediated antibody secretion. These novel observations demonstrate a role for the Breg cell in germinal center reactions and suggest that deficient activities might impair the TFH cell-dependent control of humoral immunity and might lead to the development of aberrant autoimmune responses. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  9. Involvement of plant stem cells or stem cell-like cells in dedifferentiation

    Directory of Open Access Journals (Sweden)

    Fangwei eJiang

    2015-11-01

    Full Text Available Dedifferentiation is the transformation of cells from a given differentiated state to a less differentiated or stem cell-like state. Stem cell-related genes play important roles in dedifferentiation, which exhibits similar histone modification and DNA methylation features to stem cell maintenance. Hence, stem cell-related factors possibly synergistically function to provide a specific niche beneficial to dedifferentiation. During callus formation in Arabidopsis petioles, cells adjacent to procambium cells (stem cell-like cells are dedifferentiated and survive more easily than other cell types. This finding indicates that stem cells or stem cell-like cells may influence the dedifferentiating niche. In this paper, we provide a brief overview of stem cell maintenance and dedifferentiation regulation. We also summarize current knowledge of genetic and epigenetic mechanisms underlying the balance between differentiation and dedifferentiation. Furthermore, we discuss the correlation of stem cells or stem cell-like cells with dedifferentiation.

  10. Stages of Renal Cell Cancer

    Science.gov (United States)

    ... cell cancer is a disease in which malignant (cancer) cells form in tubules of the kidney. Renal cell ... diagnosed, tests are done to find out if cancer cells have spread within the kidney or to other ...

  11. Membrane Cells for Brine Electrolysis.

    Science.gov (United States)

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  12. Membrane Cells for Brine Electrolysis.

    Science.gov (United States)

    Tingle, M.

    1982-01-01

    Membrane cells were developed as alternatives to mercury and diaphragm cells for the electrolysis of brine. Compares the three types of cells, focusing on the advantages and disadvantages of membrane cells. (JN)

  13. High Red Blood Cell Count

    Science.gov (United States)

    Symptoms High red blood cell count By Mayo Clinic Staff A high red blood cell count is an increase in oxygen-carrying cells in your bloodstream. Red blood cells transport oxygen from your lungs to tissues throughout ...

  14. Cutaneous hamartoma with pagetoid cells.

    Science.gov (United States)

    Piérard-Franchimont, C; Dosal, F L; Estrada, J A; Piérard, G E

    1991-04-01

    We report an unusual cutaneous hamartoma with pagetoid cells characterized by the presence of intraepidermal cells resembling Toker's cells of the nipple. These cells were EMA positive and could be related to the histogenesis of some Paget's disease.

  15. Cell to substratum and cell to cell interactions of microalgae.

    Science.gov (United States)

    Ozkan, Altan; Berberoglu, Halil

    2013-12-01

    This paper reports the cell to substratum and cell to cell interactions of a diverse group of microalgae based on the Extended Derjaguin, Landau, Verwey, Overbeek (XDLVO) approach using the previously reported physico-chemical surface properties. The microalgae included 10 different species of green algae and diatoms from both freshwater and saltwater environments while the substrata included glass, indium-tin oxide (ITO), stainless steel, polycarbonate, polyethylene, and polystryrene. The results indicated that acid-base interactions were the dominating mechanism of interaction for microalgae. For green algae, if at least one of the interacting surfaces was hydrophobic, adhesion at primary minimum was predicted without any energy barrier. However, most diatom systems featured energy barriers for adhesion due to repulsive van der Waals interactions. The results reported in this study are expected to provide useful data and insight into the interaction mechanisms of microalgae cells with each other and with substrata for a number of practical applications including prevention of biofouling of photobioreactors and other man-made surfaces, promotion of biofilm formation in algal biofilm photobioreactors, and developing bioflocculation strategies for energy efficient harvesting of algal biomass. Particularly, Botryococcus braunii and Cerithiopsis fusiformis were identified as promising species for biofloccuation and biofilm formation in freshwater and saltwater aquatic systems, respectively. Finally, based on the observed trends in this study, use of hydrophilic algae and hydrophilic coatings over surfaces are recommended for minimizing biofouling in aquatic systems.

  16. PEROVSKITE SOLAR CELLS (REVIEW ARTICLE)

    OpenAIRE

    Benli, Deniz Ahmet

    2015-01-01

    A solar cell is a device that converts sunlight into electricity. There are different types of solar cells but this report mainly focuses on a type of new generation solar cell that has the name organo-metal halide perovskite, shortly perovskite solar cells. In this respect, the efficiency of power conversion is taken into account to replace the dominancy of traditional and second generation solar cell fields by perovskite solar cells. Perovskite solar cell is a type of solar cell including a...

  17. Cell-to-cell transmission can overcome multiple donor and target cell barriers imposed on cell-free HIV.

    Science.gov (United States)

    Zhong, Peng; Agosto, Luis M; Ilinskaya, Anna; Dorjbal, Batsukh; Truong, Rosaline; Derse, David; Uchil, Pradeep D; Heidecker, Gisela; Mothes, Walther

    2013-01-01

    Virus transmission can occur either by a cell-free mode through the extracellular space or by cell-to-cell transmission involving direct cell-to-cell contact. The factors that determine whether a virus spreads by either pathway are poorly understood. Here, we assessed the relative contribution of cell-free and cell-to-cell transmission to the spreading of the human immunodeficiency virus (HIV). We demonstrate that HIV can spread by a cell-free pathway if all the steps of the viral replication cycle are efficiently supported in highly permissive cells. However, when the cell-free path was systematically hindered at various steps, HIV transmission became contact-dependent. Cell-to-cell transmission overcame barriers introduced in the donor cell at the level of gene expression and surface retention by the restriction factor tetherin. Moreover, neutralizing antibodies that efficiently inhibit cell-free HIV were less effective against cell-to-cell transmitted virus. HIV cell-to-cell transmission also efficiently infected target T cells that were relatively poorly susceptible to cell-free HIV. Importantly, we demonstrate that the donor and target cell types influence critically the extent by which cell-to-cell transmission can overcome each barrier. Mechanistically, cell-to-cell transmission promoted HIV spread to more cells and infected target cells with a higher proviral content than observed for cell-free virus. Our data demonstrate that the frequently observed contact-dependent spread of HIV is the result of specific features in donor and target cell types, thus offering an explanation for conflicting reports on the extent of cell-to-cell transmission of HIV.

  18. Cell-to-cell transmission can overcome multiple donor and target cell barriers imposed on cell-free HIV.

    Directory of Open Access Journals (Sweden)

    Peng Zhong

    Full Text Available Virus transmission can occur either by a cell-free mode through the extracellular space or by cell-to-cell transmission involving direct cell-to-cell contact. The factors that determine whether a virus spreads by either pathway are poorly understood. Here, we assessed the relative contribution of cell-free and cell-to-cell transmission to the spreading of the human immunodeficiency virus (HIV. We demonstrate that HIV can spread by a cell-free pathway if all the steps of the viral replication cycle are efficiently supported in highly permissive cells. However, when the cell-free path was systematically hindered at various steps, HIV transmission became contact-dependent. Cell-to-cell transmission overcame barriers introduced in the donor cell at the level of gene expression and surface retention by the restriction factor tetherin. Moreover, neutralizing antibodies that efficiently inhibit cell-free HIV were less effective against cell-to-cell transmitted virus. HIV cell-to-cell transmission also efficiently infected target T cells that were relatively poorly susceptible to cell-free HIV. Importantly, we demonstrate that the donor and target cell types influence critically the extent by which cell-to-cell transmission can overcome each barrier. Mechanistically, cell-to-cell transmission promoted HIV spread to more cells and infected target cells with a higher proviral content than observed for cell-free virus. Our data demonstrate that the frequently observed contact-dependent spread of HIV is the result of specific features in donor and target cell types, thus offering an explanation for conflicting reports on the extent of cell-to-cell transmission of HIV.

  19. Nanofluidic fuel cell

    Science.gov (United States)

    Lee, Jin Wook; Kjeang, Erik

    2013-11-01

    Fuel cells are gaining momentum as a critical component in the renewable energy mix for stationary, transportation, and portable power applications. State-of-the-art fuel cell technology benefits greatly from nanotechnology applied to nanostructured membranes, catalysts, and electrodes. However, the potential of utilizing nanofluidics for fuel cells has not yet been explored, despite the significant opportunity of harnessing rapid nanoscale reactant transport in close proximity to the reactive sites. In the present article, a nanofluidic fuel cell that utilizes fluid flow through nanoporous media is conceptualized and demonstrated for the first time. This transformative concept captures the advantages of recently developed membraneless and catalyst-free fuel cell architectures paired with the enhanced interfacial contact area enabled by nanofluidics. When compared to previously reported microfluidic fuel cells, the prototype nanofluidic fuel cell demonstrates increased surface area, reduced activation overpotential, superior kinetic characteristics, and moderately enhanced fuel cell performance in the high cell voltage regime with up to 14% higher power density. However, the expected mass transport benefits in the high current density regime were constrained by high ohmic cell resistance, which could likely be resolved through future optimization studies.

  20. Biology of Schwann cells.

    Science.gov (United States)

    Kidd, Grahame J; Ohno, Nobuhiko; Trapp, Bruce D

    2013-01-01

    The fundamental roles of Schwann cells during peripheral nerve formation and regeneration have been recognized for more than 100 years, but the cellular and molecular mechanisms that integrate Schwann cell and axonal functions continue to be elucidated. Derived from the embryonic neural crest, Schwann cells differentiate into myelinating cells or bundle multiple unmyelinated axons into Remak fibers. Axons dictate which differentiation path Schwann cells follow, and recent studies have established that axonal neuregulin1 signaling via ErbB2/B3 receptors on Schwann cells is essential for Schwann cell myelination. Extracellular matrix production and interactions mediated by specific integrin and dystroglycan complexes are also critical requisites for Schwann cell-axon interactions. Myelination entails expansion and specialization of the Schwann cell plasma membrane over millimeter distances. Many of the myelin-specific proteins have been identified, and transgenic manipulation of myelin genes have provided novel insights into myelin protein function, including maintenance of axonal integrity and survival. Cellular events that facilitate myelination, including microtubule-based protein and mRNA targeting, and actin based locomotion, have also begun to be understood. Arguably, the most remarkable facet of Schwann cell biology, however, is their vigorous response to axonal damage. Degradation of myelin, dedifferentiation, division, production of axonotrophic factors, and remyelination all underpin the substantial regenerative capacity of the Schwann cells and peripheral nerves. Many of these properties are not shared by CNS fibers, which are myelinated by oligodendrocytes. Dissecting the molecular mechanisms responsible for the complex biology of Schwann cells continues to have practical benefits in identifying novel therapeutic targets not only for Schwann cell-specific diseases but other disorders in which axons degenerate. Copyright © 2013 Elsevier B.V. All rights

  1. The Chlamydomonas cell cycle.

    Science.gov (United States)

    Cross, Frederick R; Umen, James G

    2015-05-01

    The position of Chlamydomonas within the eukaryotic phylogeny makes it a unique model in at least two important ways: as a representative of the critically important, early-diverging lineage leading to plants; and as a microbe retaining important features of the last eukaryotic common ancestor (LECA) that has been lost in the highly studied yeast lineages. Its cell biology has been studied for many decades and it has well-developed experimental genetic tools, both classical (Mendelian) and molecular. Unlike land plants, it is a haploid with very few gene duplicates, making it ideal for loss-of-function genetic studies. The Chlamydomonas cell cycle has a striking temporal and functional separation between cell growth and rapid cell division, probably connected to the interplay between diurnal cycles that drive photosynthetic cell growth and the cell division cycle; it also exhibits a highly choreographed interaction between the cell cycle and its centriole-basal body-flagellar cycle. Here, we review the current status of studies of the Chlamydomonas cell cycle. We begin with an overview of cell-cycle control in the well-studied yeast and animal systems, which has yielded a canonical, well-supported model. We discuss briefly what is known about similarities and differences in plant cell-cycle control, compared with this model. We next review the cytology and cell biology of the multiple-fission cell cycle of Chlamydomonas. Lastly, we review recent genetic approaches and insights into Chlamydomonas cell-cycle regulation that have been enabled by a new generation of genomics-based tools. © 2015 The Authors The Plant Journal published by Society for Experimental Biology and John Wiley & Sons Ltd.

  2. Cell-Substrate Adhesion by Amoeboid Cells

    Science.gov (United States)

    Flanders, Bret; Panta, Krishna

    Amoeboid migration is a rapid (10 μm min-1) mode of migration that some tumor cells exhibit. To permit such rapid movement, the adhesive contacts between the cell and the substrate must be relatively short-lived and weak. In this study, we investigate the basic adhesive character of amoeboid cells (D. discoideum) in contact with silanized glass substrates. We observe the initiation and spreading of the adhesive contacts that these cells establish as they settle under gravity onto the substrate and relax towards mechanical equilibrium. The use of interference reflection microscopy and cellular tethering measurements have allowed us to determine the basic adhesive properties of the cell: the membrane-medium interfacial energy; the bending modulus; the equilibrium contact angle; and the work of adhesion. We find the time scale on which settling occurs to be longer than expected. Implications of these results on adhesion and migration will be discussed. The authors are grateful for support from NSF (CBET-1451903) and NIH (1R21EY026392).

  3. Isolation of rare cancer cells from blood cells using dielectrophoresis.

    Science.gov (United States)

    Salmanzadeh, Alireza; Sano, Michael B; Shafiee, Hadi; Stremler, Mark A; Davalos, Rafael V

    2012-01-01

    In this study, we investigate the application of contactless dielectrophoresis (cDEP) for isolating cancer cells from blood cells. Devices with throughput of 0.2 mL/hr (equivalent to sorting 3×10(6) cells per minute) were used to trap breast cancer cells while allowing blood cells through. We have shown that this technique is able to isolate cancer cells in concentration as low as 1 cancer cell per 10(6) hematologic cells (equivalent to 1000 cancer cells in 1 mL of blood). We achieved 96% trapping of the cancer cells at 600 kHz and 300 V(RMS).

  4. Embryonic stem cell-somatic cell fusion and postfusion enucleation.

    Science.gov (United States)

    Sumer, Huseyin; Verma, Paul J

    2015-01-01

    Embryonic stem (ES) cells are able to reprogram somatic cells following cell fusion. The resulting cell hybrids have been shown to have similar properties to pluripotent cells. It has also been shown that transcriptional changes can occur in a heterokaryon, without nuclear hybridization. However it is unclear whether these changes can be sustained following removal of the dominant ES nucleus. In this chapter, methods are described for the cell fusion of mouse tetraploid ES cells with somatic cells and enrichment of the resulting heterokaryons. We next describe the conditions for the differential removal of the ES cell nucleus, allowing for the recovery of somatic cells.

  5. New Cell Sources for T Cell Engineering and Adoptive Immunotherapy

    Science.gov (United States)

    Themeli, Maria; Rivière, Isabelle; Sadelain, Michel

    2017-01-01

    The promising clinical results obtained with engineered T cells, including chimeric antigen receptor (CAR) therapy, call for further advancements to facilitate and broaden their applicability. One potentially beneficial innovation is to exploit new T cell sources that reduce the need for autologous cell manufacturing and enable cell transfer across histocompatibility barriers. Here we review emerging T cell engineering approaches that utilize alternative T cell sources, which include virus-specific or T cell receptor-less allogeneic T cells, expanded lymphoid progenitors, and induced pluripotent stem cell (iPSC)-derived T lymphocytes. The latter offer the prospect for true off-the-shelf, genetically enhanced, histocompatible cell therapy products. PMID:25842976

  6. Myoepithelial cells in pathology

    Directory of Open Access Journals (Sweden)

    N Balachander

    2015-01-01

    Full Text Available Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  7. Melanoma stem cells.

    Science.gov (United States)

    Roesch, Alexander

    2015-02-01

    The cancer stem cell concept significantly broadens our understanding of melanoma biology. However, this concept should be regarded as an integral part of a holistic cancer model that also includes the genetic evolution of tumor cells and the variability of cell phenotypes within a dynamic tumor microenvironment. The biologic complexity and methodological difficulties in identifying cancer stem cells and their biomarkers are currently impeding the direct translation of experimental findings into clinical practice. Nevertheless, it is these methodological shortcomings that provide a new perspective on the phenotypic heterogeneity and plasticity of melanoma with important consequences for future therapies. The development of new combination treatment strategies, particularly with regard to overcoming treatment resistance, could significantly benefit from targeted elimination of cell subpopulations with cancer stem cell properties. © 2015 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  8. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Amitkumar B Pandav

    2012-01-01

    Full Text Available Plasma cell granuloma, also known as inflammatory pseudotumor is a tumor-like lesion that manifests primarily in the lungs. But it may occur in various other anatomic locations like orbit, head and neck, liver and rarely in the oral cavity. We here report an exceedingly rare case of gingival plasma cell granuloma in a 58 year old woman who presented with upper gingival polypoidal growth. The histopathological examination revealed a mass composed of proliferation of benign spindle mesenchymal cells in a loose myxoid and fibrocollagenous stroma along with dense infiltrate of chronic inflammatory cells predominantly containing plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma.

  9. Regulatory T cell memory

    Science.gov (United States)

    Rosenblum, Michael D.; Way, Sing Sing; Abbas, Abul K.

    2016-01-01

    Memory for antigen is a defining feature of adaptive immunity. Antigen-specific lymphocyte populations show an increase in number and function after antigen encounter and more rapidly re-expand upon subsequent antigen exposure. Studies of immune memory have primarily focused on effector B cells and T cells with microbial specificity, using prime challenge models of infection. However, recent work has also identified persistently expanded populations of antigen-specific regulatory T cells that protect against aberrant immune responses. In this Review, we consider the parallels between memory effector T cells and memory regulatory T cells, along with the functional implications of regulatory memory in autoimmunity, antimicrobial host defence and maternal fetal tolerance. In addition, we discuss emerging evidence for regulatory T cell memory in humans and key unanswered questions in this rapidly evolving field. PMID:26688349

  10. Trafficking and cell migration.

    Science.gov (United States)

    Ulrich, Florian; Heisenberg, Carl-Philipp

    2009-07-01

    The migration of single cells and epithelial sheets is of great importance for gastrulation and organ formation in developing embryos and, if misregulated, can have dire consequences e.g. during cancer metastasis. A keystone of cell migration is the regulation of adhesive contacts, which are dynamically assembled and disassembled via endocytosis. Here, we discuss some of the basic concepts about the function of endocytic trafficking during cell migration: transport of integrins from the cell rear to the leading edge in fibroblasts; confinement of signalling to the front of single cells by endocytic transport of growth factors; regulation of movement coherence in multicellular sheets by cadherin turnover; and shaping of extracellular chemokine gradients. Taken together, endocytosis enables migrating cells and tissues to dynamically modulate their adhesion and signalling, allowing them to efficiently migrate through their extracellular environment.

  11. Cell Factory Engineering

    DEFF Research Database (Denmark)

    Davy, Anne Mathilde; Kildegaard, Helene Faustrup; Andersen, Mikael Rørdam

    2017-01-01

    Rational approaches to modifying cells to make molecules of interest are of substantial economic and scientific interest. Most of these efforts aim at the production of native metabolites, expression of heterologous biosynthetic pathways, or protein expression. Reviews of these topics have largely...... focused on individual strategies or cell types, but collectively they fall under the broad umbrella of a growing field known as cell factory engineering. Here we condense >130 reviews and key studies in the art into a meta-review of cell factory engineering. We identified 33 generic strategies...... in the field, all applicable to multiple types of cells and products, and proven successful in multiple major cell types. These apply to three major categories: production of native metabolites and/or bioactives, heterologous expression of biosynthetic pathways, and protein expression. This meta...

  12. NCAM regulates cell motility

    DEFF Research Database (Denmark)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna

    2002-01-01

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells...... independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment...... to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine...

  13. Cytoskeleton and Cell Motility

    CERN Document Server

    Risler, Thomas

    2011-01-01

    The present article is an invited contribution to the Encyclopedia of Complexity and System Science, Robert A. Meyers Ed., Springer New York (2009). It is a review of the biophysical mechanisms that underly cell motility. It mainly focuses on the eukaryotic cytoskeleton and cell-motility mechanisms. Bacterial motility as well as the composition of the prokaryotic cytoskeleton is only briefly mentioned. The article is organized as follows. In Section III, I first present an overview of the diversity of cellular motility mechanisms, which might at first glance be categorized into two different types of behaviors, namely "swimming" and "crawling". Intracellular transport, mitosis - or cell division - as well as other extensions of cell motility that rely on the same essential machinery are briefly sketched. In Section IV, I introduce the molecular machinery that underlies cell motility - the cytoskeleton - as well as its interactions with the external environment of the cell and its main regulatory pathways. Sec...

  14. Myoepithelial cells in pathology.

    Science.gov (United States)

    Balachander, N; Masthan, K M K; Babu, N Aravindha; Anbazhagan, V

    2015-04-01

    Myoepithelial cells are a normal constituent of the salivary acini and ducts and are found between the epithelial cells and the basement membrane. Microscopically myoepithelial cells are thin and spindle-shaped and ultrastructurally they possess a number of Cytoplasmic processes that extend between and over the acinar and ductal-lining cells, and they show features of both smooth muscle and epithelium. They play a vital role during expulsion of saliva and regulates the electrolytic exchange. They also perform as tumor suppressors and are considered to play a very important role in differentiation of various salivary gland tumors and help in the diagnosis of tumors. Neoplastic myoepithelial cells in both benign and malignant tumors can take numerous forms including epithelioid, plasmacytoid, spindle and clear cell variant, and this variability largely accounts for difficulties in histopathological diagnosis.

  15. Aneuploidy in stem cells

    Institute of Scientific and Technical Information of China (English)

    Jorge; Garcia-Martinez; Bjorn; Bakker; Klaske; M; Schukken; Judith; E; Simon; Floris; Foijer

    2016-01-01

    Stem cells hold enormous promise for regenerative medicine as well as for engineering of model systems to study diseases and develop new drugs. The discovery of protocols that allow for generating induced pluripotent stem cells(IPSCs) from somatic cells has brought this promise steps closer to reality. However,as somatic cells might have accumulated various chromosomal abnormalities,including aneuploidies throughout their lives,the resulting IPSCs might no longer carry the perfect blueprint for the tissue to be generated,or worse,become at risk of adopting a malignant fate. In this review,we discuss the contribution of aneuploidy to healthy tissues and how aneuploidy can lead to disease. Furthermore,we review the differences between how somatic cells and stem cells respond to aneuploidy.

  16. Mechanical plasticity of cells

    Science.gov (United States)

    Bonakdar, Navid; Gerum, Richard; Kuhn, Michael; Spörrer, Marina; Lippert, Anna; Schneider, Werner; Aifantis, Katerina E.; Fabry, Ben

    2016-10-01

    Under mechanical loading, most living cells show a viscoelastic deformation that follows a power law in time. After removal of the mechanical load, the cell shape recovers only incompletely to its original undeformed configuration. Here, we show that incomplete shape recovery is due to an additive plastic deformation that displays the same power-law dynamics as the fully reversible viscoelastic deformation response. Moreover, the plastic deformation is a constant fraction of the total cell deformation and originates from bond ruptures within the cytoskeleton. A simple extension of the prevailing viscoelastic power-law response theory with a plastic element correctly predicts the cell behaviour under cyclic loading. Our findings show that plastic energy dissipation during cell deformation is tightly linked to elastic cytoskeletal stresses, which suggests the existence of an adaptive mechanism that protects the cell against mechanical damage.

  17. Induced pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Siddhartha Bhowmik; LI Yong

    2011-01-01

    Induced pluripotent stem (iPS) cells are a recent development which has brought a promise of great therapeutic values. The previous technique of somatic cell nuclear transfer (SCNT) has been ineffective in humans. Recent discoveries show that human fibroblasts can be reprogrammed by a transient over expression of a small number of genes; they can undergo induced pluripotency. iPS were first produced in 2006. By 2008, work was underway to remove the potential oncogenes from their structure. In 2009, protein iPS (piPS) cells were discovered. Surface markers and reporter genes play an important role in stem cell research. Clinical applications include generation of self renewing stem cells, tissue replacement and many more. Stem cell therapy has the ability to dramatically change the treatment of human diseases.

  18. Fish germ cells

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Fish, like many other animals, have two major cell lineages, namely the germline and soma. The germ-soma separation is one of the earliest events of embryonic development. Germ cells can be specifically labeled and isolated for culture and transplan-tation, providing tools for reproduction of endangered species in close relatives, such as surrogate production of trout in salmon. Haploid cell cultures, such as medaka haploid embryonic stem cells have recently been obtained, which are capable of mimicking sperm to produce fertile offspring, upon nuclear being directly transferred into normal eggs. Such fish originated from a mosaic oocyte that had a haploid meiotic nucleus and a transplanted haploid mitotic cell culture nucleus. The first semi-cloned fish is Holly. Here we review the current status and future directions of understanding and manipulating fish germ cells in basic research and reproductive technology.

  19. Gingival plasma cell granuloma

    Directory of Open Access Journals (Sweden)

    Phadnaik Mangesh

    2010-01-01

    Full Text Available Plasma cell granuloma is a rare reactive lesion composed of polyclonal plasma cells. It manifests primarily in the lungs, but may occur in various other anatomic locations like the oral cavity. Intraoral plasma cell granulomas involving the tongue, lip, oral mucosa and gingiva have been reported in the past. This case presents a 54-year-old female with chronic periodontitis and mandibular anterior gingival overgrowth treated by Phase I therapy (scaling and root planing and excisional biopsy. Histological examination revealed inflammatory cell infiltrate containing sheets of plasma cells. Immunohistochemistry for kappa and lambda light chains showed a polyclonal staining pattern confirming a diagnosis of plasma cell granuloma. This case highlights the need to biopsy for unusual lesions to rule out potential neoplasms.

  20. Mammary epithelial cell

    DEFF Research Database (Denmark)

    Kass, Laura; Erler, Janine Terra; Dembo, Micah

    2007-01-01

    a repertoire of transmembrane receptors, of which integrins are the best characterized. Integrins modulate cell fate by reciprocally transducing biochemical and biophysical cues between the cell and the extracellular matrix, facilitating processes such as embryonic branching morphogenesis and lactation...... in the mammary gland. During breast development and cancer progression, the extracellular matrix is dynamically altered such that its composition, turnover, processing and orientation change dramatically. These modifications influence mammary epithelial cell shape, and modulate growth factor and hormonal...

  1. Immobilized Cell Research

    Science.gov (United States)

    1990-10-31

    beads, the plasmid is twice as stable as in cells In a process where immobilized cells produce material grown in continuous culture over 200...carrageenan) or chemically cross-linked, or- Penicillium chrysogenum than in washed freely suspended ganic polymer (Ca-alginate, polyacrylamide, and mycelium ...these materials are formed into the freely suspended cells stopped after 6 days. If the beads of several millimeters in diameter by allowing the

  2. Cell Wall Proteome

    OpenAIRE

    Boudart, Georges; Minic, Zoran; Albenne, Cécile; Canut, Hervé; Jamet, Elisabeth; Pont-Lezica, Rafael F

    2007-01-01

    In this chapter, we will focus on the contribution of proteomics to the identification and determination of the structure and function of CWPs as well as discussing new perspectives in this area. The great variety of proteins found in the plant cell wall is described. Some families, such as glycoside hydrolases, proteases, lectins, and inhibitors of cell wall modifying enzymes, are discussed in detail. Examples of the use of proteomic techniques to elucidate the structure of various cell wall...

  3. Direct hydrocarbon fuel cells

    Science.gov (United States)

    Barnett, Scott A.; Lai, Tammy; Liu, Jiang

    2010-05-04

    The direct electrochemical oxidation of hydrocarbons in solid oxide fuel cells, to generate greater power densities at lower temperatures without carbon deposition. The performance obtained is comparable to that of fuel cells used for hydrogen, and is achieved by using novel anode composites at low operating temperatures. Such solid oxide fuel cells, regardless of fuel source or operation, can be configured advantageously using the structural geometries of this invention.

  4. Lymphomas of large cells.

    Science.gov (United States)

    Staples, W G; Gétaz, E P

    1977-09-03

    Historial aspects of the classification of large-cell lymphomas are described. Immunological characterization of the lymphomas has been made possible by identification of T and B lymphocytes according to their cell membrane surface characteristics. The pathogenesis of lymphomas has been clarified by the germinal (follicular) centre cell concepts of Lennert and Lukes and Collins. The various classifications are presented and compared. Whether these subdivisions will have any relevance in the clinical context remains to be seen.

  5. Systems cell biology.

    Science.gov (United States)

    Mast, Fred D; Ratushny, Alexander V; Aitchison, John D

    2014-09-15

    Systems cell biology melds high-throughput experimentation with quantitative analysis and modeling to understand many critical processes that contribute to cellular organization and dynamics. Recently, there have been several advances in technology and in the application of modeling approaches that enable the exploration of the dynamic properties of cells. Merging technology and computation offers an opportunity to objectively address unsolved cellular mechanisms, and has revealed emergent properties and helped to gain a more comprehensive and fundamental understanding of cell biology.

  6. Cells as Drops and Drops as Cells

    Science.gov (United States)

    Dufresne, Eric R.

    2013-03-01

    How do the mechanical properties of tissues emerge from the interactions of individual cells? To shed some light on this fundamental biological question, we consider a model system of clusters of cohesive cells adherent to soft substrates. We quantify traction forces over a wide range of cluster sizes. The scaling of traction stresses with cluster size suggests the emergence of an apparent surface tension for large colonies. To explore the possible impact of cellular surface tension on physiology, we consider the behavior of liquid droplets on soft substrates. In this case, we find that the competition of surface tension and substrate elasticity can lead to rich phenomenology, mimicking certain aspects of the physiology of cells and tissues.

  7. Differentiated human stem cells resemble fetal, not adult, β cells.

    Science.gov (United States)

    Hrvatin, Sinisa; O'Donnell, Charles W; Deng, Francis; Millman, Jeffrey R; Pagliuca, Felicia Walton; DiIorio, Philip; Rezania, Alireza; Gifford, David K; Melton, Douglas A

    2014-02-25

    Human pluripotent stem cells (hPSCs) have the potential to generate any human cell type, and one widely recognized goal is to make pancreatic β cells. To this end, comparisons between differentiated cell types produced in vitro and their in vivo counterparts are essential to validate hPSC-derived cells. Genome-wide transcriptional analysis of sorted insulin-expressing (INS(+)) cells derived from three independent hPSC lines, human fetal pancreata, and adult human islets points to two major conclusions: (i) Different hPSC lines produce highly similar INS(+) cells and (ii) hPSC-derived INS(+) (hPSC-INS(+)) cells more closely resemble human fetal β cells than adult β cells. This study provides a direct comparison of transcriptional programs between pure hPSC-INS(+) cells and true β cells and provides a catalog of genes whose manipulation may convert hPSC-INS(+) cells into functional β cells.

  8. Origins of pluripotent stem cells.

    Science.gov (United States)

    Roelen, B A J; Chuva De Sousa Lopes, S M

    2011-08-01

    Different types of pluripotent stem cells can be identified and cultured in vitro. Here an overview is presented of the various pluripotent stem cells types. Embryonal carcinoma (EC) cells that have been cultured in vitro provided the groundwork for future pluripotent cell cultures. Conditions established for these cells such as culture on a feeder layer of mouse embryonic fibroblasts and the importance of fetal calf serum were initially also used for the culture of mouse embryonic stem (ES) cells derived from the inner cell masses of blastocysts. Embryonic stem cells derived from human blastocysts were found to require different conditions and are cultured in the presence of activin and basic fibroblast growth factor. Recently pluripotent stem cells have also been derived from mouse peri-implantation epiblasts. Since these epiblast stem cells (EpiSCs) require the same conditions as the human ES cells it has been suggested that human ES cells are more similar to mouse EpiSCs than to mouse ES cells. Pluripotent cell lines have also been derived from migratory primordial germ cells and spermatogonial stem cells. The creation of pluripotent stem cells from adult cells by the introduction of reprogramming transcription factors, so-called induced pluripotent stem (iPS) cells allowed the derivation of patient-specific pluripotent stem cells without the need of creation of a human blastocyst after cloning by somatic cells nuclear transfer. Recently it has become clear however that iPS cells may be quite different to ES cells in terms of epigenetics.

  9. Microencapsulation Of Living Cells

    Science.gov (United States)

    Chang, Manchium; Kendall, James M.; Wang, Taylor G.

    1989-01-01

    In experimental technique, living cells and other biological materials encapsulated within submillimeter-diameter liquid-filled spheres. Sphere material biocompatible, tough, and compliant. Semipermeable, permitting relatively small molecules to move into and out of sphere core but preventing passage of large molecules. New technique promises to make such spherical capsules at high rates and in uniform, controllable sizes. Capsules injected into patient through ordinary hypodermic needle. Promising application for technique in treatment of diabetes. Also used to encapsulate pituitary cells and thyroid hormone adrenocortical cells for treatment of other hormonal disorders, to encapsulate other secreting cells for transplantation, and to package variety of pharmaceutical products and agricultural chemicals for controlled release.

  10. [Endothelial cell adhesion molecules].

    Science.gov (United States)

    Ivanov, A N; Norkin, I A; Puchin'ian, D M; Shirokov, V Iu; Zhdanova, O Iu

    2014-01-01

    The review presents current data concerning the functional role of endothelial cell adhesion molecules belonging to different structural families: integrins, selectins, cadherins, and the immunoglobulin super-family. In this manuscript the regulatory mechanisms and factors of adhesion molecules expression and distribution on the surface of endothelial cells are discussed. The data presented reveal the importance of adhesion molecules in the regulation of structural and functional state of endothelial cells in normal conditions and in pathology. Particular attention is paid to the importance of these molecules in the processes of physiological and pathological angiogenesis, regulation of permeability of the endothelial barrier and cell transmigration.

  11. Assessment of cell viability.

    Science.gov (United States)

    Johnson, Simon; Nguyen, Vy; Coder, David

    2013-01-01

    Cell viability may be judged by morphological changes or by changes in membrane permeability and/or physiological state inferred from the exclusion of certain dyes or the uptake and retention of others. This unit presents methods based on dye exclusion, esterase activity, and mitochondrial membrane potential, as well as protocols for determining the pre-fixation viability of fixed cells either before or after fixation with amine-reactive dyes suitable for a range of excitation wavelengths. Membrane-impermeable dead cell and live cell dyes as well as dye-exclusion procedures for microscopy are also included.

  12. Giant Cell Arteritis

    Science.gov (United States)

    ... Cryopyrin-Associated Autoinflammatory Syndrome (CAPS) (Juvenile) Dermatomyositis (Juvenile) Familial Mediterranean Fever (Juvenile) Fibromyalgia Giant Cell Arteritis Glucocorticoid-induced Osteoperosis ...

  13. Analysing immune cell migration.

    Science.gov (United States)

    Beltman, Joost B; Marée, Athanasius F M; de Boer, Rob J

    2009-11-01

    The visualization of the dynamic behaviour of and interactions between immune cells using time-lapse video microscopy has an important role in modern immunology. To draw robust conclusions, quantification of such cell migration is required. However, imaging experiments are associated with various artefacts that can affect the estimated positions of the immune cells under analysis, which form the basis of any subsequent analysis. Here, we describe potential artefacts that could affect the interpretation of data sets on immune cell migration. We propose how these errors can be recognized and corrected, and suggest ways to prevent the data analysis itself leading to biased results.

  14. Applications of Cell Microencapsulation.

    Science.gov (United States)

    Opara, Emmanuel C

    2017-01-01

    The goal of this chapter is to provide an overview of the different purposes for which the cell microencapsulation technology can be used. These include immunoisolation of non-autologous cells used for cell therapy; immobilization of cells for localized (targeted) delivery of therapeutic products to ablate, repair, or regenerate tissue; simultaneous delivery of multiple therapeutic agents in cell therapy; spatial compartmentalization of cells in complex tissue engineering; expansion of cells in culture; and production of different probiotics and metabolites for industrial applications. For each of these applications, specific examples are provided to illustrate how the microencapsulation technology can be utilized to achieve the purpose. However, successful use of the cell microencapsulation technology for whatever purpose will ultimately depend upon careful consideration for the choice of the encapsulating polymers, the method of fabrication (cross-linking) of the microbeads, which affects the permselectivity, the biocompatibility and the mechanical strength of the microbeads as well as environmental parameters such as temperature, humidity, osmotic pressure, and storage solutions.The various applications discussed in this chapter are illustrated in the different chapters of this book and where appropriate relevant images of the microencapsulation products are provided. It is hoped that this outline of the different applications of cell microencapsulation would provide a good platform for tissue engineers, scientists, and clinicians to design novel tissue constructs and products for therapeutic and industrial applications.

  15. Cell sorting in development.

    Science.gov (United States)

    Krens, S F Gabby; Heisenberg, Carl-Philipp

    2011-01-01

    During the development of multicellular organisms, cell fate specification is followed by the sorting of different cell types into distinct domains from where the different tissues and organs are formed. Cell sorting involves both the segregation of a mixed population of cells with different fates and properties into distinct domains, and the active maintenance of their segregated state. Because of its biological importance and apparent resemblance to fluid segregation in physics, cell sorting was extensively studied by both biologists and physicists over the last decades. Different theories were developed that try to explain cell sorting on the basis of the physical properties of the constituent cells. However, only recently the molecular and cellular mechanisms that control the physical properties driving cell sorting, have begun to be unraveled. In this review, we will provide an overview of different cell-sorting processes in development and discuss how these processes can be explained by the different sorting theories, and how these theories in turn can be connected to the molecular and cellular mechanisms driving these processes.

  16. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan [Univ. of California, Berkeley, CA (United States)

    2006-01-01

    This dissertation presents the results of a research agenda aimed at improving integration and stability in nanocrystal-based solar cells through advances in active materials and device architectures. The introduction of 3-dimensional nanocrystals illustrates the potential for improving transport and percolation in hybrid solar cells and enables novel fabrication methods for optimizing integration in these systems. Fabricating cells by sequential deposition allows for solution-based assembly of hybrid composites with controlled and well-characterized dispersion and electrode contact. Hyperbranched nanocrystals emerge as a nearly ideal building block for hybrid cells, allowing the controlled morphologies targeted by templated approaches to be achieved in an easily fabricated solution-cast device. In addition to offering practical benefits to device processing, these approaches offer fundamental insight into the operation of hybrid solar cells, shedding light on key phenomena such as the roles of electrode-contact and percolation behavior in these cells. Finally, all-inorganic nanocrystal solar cells are presented as a wholly new cell concept, illustrating that donor-acceptor charge transfer and directed carrier diffusion can be utilized in a system with no organic components, and that nanocrystals may act as building blocks for efficient, stable, and low-cost thin-film solar cells.

  17. Rapid cooled lens cell

    Science.gov (United States)

    Stubbs, David M.; Hsu, Ike C.

    1991-12-01

    This paper describes the optomechanical design, thermal analysis, fabrication, and test evaluation processes followed in developing a rapid cooled, infrared lens cell. Thermal analysis was the key engineering discipline exercised in the design phase. The effect of thermal stress on the lens, induced by rapid cooling of the lens cell, was investigated. Features of this lens cell that minimized the thermal stress will be discussed in a dedicated section. The results of thermal analysis on the selected lens cell design and the selection of the flow channel design in the heat exchanger will be discussed. Throughout the paper engineering drawings, illustrations, analytical results, and photographs of actual hardware are presented.

  18. Cancer stem cell metabolism

    National Research Council Canada - National Science Library

    Peiris-Pagès, Maria; Martinez-Outschoorn, Ubaldo E; Pestell, Richard G; Sotgia, Federica; Lisanti, Michael P

    2016-01-01

    .... Cancer stem cells also seem to adapt their metabolism to microenvironmental changes by conveniently shifting energy production from one pathway to another, or by acquiring intermediate metabolic phenotypes...

  19. Littoral Cells 2005

    Data.gov (United States)

    California Department of Resources — Littoral cells along the California Coast. Originally digitized by Melanie Coyne from the Assessment and Atlas of Shoreline Erosion Along the California Coast...

  20. Littoral Cells 2005

    Data.gov (United States)

    California Department of Resources — Littoral cells along the California Coast. Originally digitized by Melanie Coyne from the Assessment and Atlas of Shoreline Erosion Along the California Coast...

  1. Beta cell dynamics: beta cell replenishment, beta cell compensation and diabetes.

    Science.gov (United States)

    Cerf, Marlon E

    2013-10-01

    Type 2 diabetes, characterized by persistent hyperglycemia, arises mostly from beta cell dysfunction and insulin resistance and remains a highly complex metabolic disease due to various stages in its pathogenesis. Glucose homeostasis is primarily regulated by insulin secretion from the beta cells in response to prevailing glycemia. Beta cell populations are dynamic as they respond to fluctuating insulin demand. Beta cell replenishment and death primarily regulate beta cell populations. Beta cells, pancreatic cells, and extra-pancreatic cells represent the three tiers for replenishing beta cells. In rodents, beta cell self-replenishment appears to be the dominant source for new beta cells supported by pancreatic cells (non-beta islet cells, acinar cells, and duct cells) and extra-pancreatic cells (liver, neural, and stem/progenitor cells). In humans, beta cell neogenesis from non-beta cells appears to be the dominant source of beta cell replenishment as limited beta cell self-replenishment occurs particularly in adulthood. Metabolic states of increased insulin demand trigger increased insulin synthesis and secretion from beta cells. Beta cells, therefore, adapt to support their physiology. Maintaining physiological beta cell populations is a strategy for targeting metabolic states of persistently increased insulin demand as in diabetes.

  2. A focus on parietal cells as a renewing cell population

    Institute of Scientific and Technical Information of China (English)

    Sherif; M; Karam

    2010-01-01

    The fact that the acidsecreting parietal cells undergo continuous renewal has been ignored by many gastroenterologists and cell biologists. In the past, it was thought that these cells were static. However, by using 3Hthymidine radioautography in combination with electron microscopy, it was possible to demonstrate that parietal cells belong to a continuously renewing epithelial cell lineage. In the gastric glands, stem cells anchored in the isthmus region are responsible for the production of parietal cells...

  3. Dedifferentiated adipocyte-derived progeny cells (DFAT cells)

    OpenAIRE

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J.; Rasmussen, Theodore P; Bergen, Werner G.; Dodson, Michael V.

    2013-01-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, ...

  4. Regulation of B Cell to Plasma Cell Transition within the Follicular B Cell Response.

    Science.gov (United States)

    Nera, K-P; Kyläniemi, M K; Lassila, O

    2015-09-01

    Persistent humoral immunity depends on the follicular B cell response and on the generation of somatically mutated high-affinity plasma cells and memory B cells. Upon activation by an antigen, cognately activated follicular B cells and follicular T helper (TFH ) cells initiate germinal centre (GC) reaction during which high-affinity effector cells are generated. The differentiation of activated follicular B cells into plasma cells and memory B cells is guided by complex selection events, both at the cellular and molecular level. The transition of B cell into a plasma cell during the GC response involves alterations in the microenvironment and developmental state of the cell, which are guided by cell-extrinsic signals. The developmental cell fate decisions in response to these signals are coordinated by cell-intrinsic gene regulatory network functioning at epigenetic, transcriptional and post-transcriptional levels.

  5. Fuel Cell Demonstration Program

    Energy Technology Data Exchange (ETDEWEB)

    Gerald Brun

    2006-09-15

    In an effort to promote clean energy projects and aid in the commercialization of new fuel cell technologies the Long Island Power Authority (LIPA) initiated a Fuel Cell Demonstration Program in 1999 with six month deployments of Proton Exchange Membrane (PEM) non-commercial Beta model systems at partnering sites throughout Long Island. These projects facilitated significant developments in the technology, providing operating experience that allowed the manufacturer to produce fuel cells that were half the size of the Beta units and suitable for outdoor installations. In 2001, LIPA embarked on a large-scale effort to identify and develop measures that could improve the reliability and performance of future fuel cell technologies for electric utility applications and the concept to establish a fuel cell farm (Farm) of 75 units was developed. By the end of October of 2001, 75 Lorax 2.0 fuel cells had been installed at the West Babylon substation on Long Island, making it the first fuel cell demonstration of its kind and size anywhere in the world at the time. Designed to help LIPA study the feasibility of using fuel cells to operate in parallel with LIPA's electric grid system, the Farm operated 120 fuel cells over its lifetime of over 3 years including 3 generations of Plug Power fuel cells (Lorax 2.0, Lorax 3.0, Lorax 4.5). Of these 120 fuel cells, 20 Lorax 3.0 units operated under this Award from June 2002 to September 2004. In parallel with the operation of the Farm, LIPA recruited government and commercial/industrial customers to demonstrate fuel cells as on-site distributed generation. From December 2002 to February 2005, 17 fuel cells were tested and monitored at various customer sites throughout Long Island. The 37 fuel cells operated under this Award produced a total of 712,635 kWh. As fuel cell technology became more mature, performance improvements included a 1% increase in system efficiency. Including equipment, design, fuel, maintenance

  6. Regulation of beta cell replication

    DEFF Research Database (Denmark)

    Lee, Ying C; Nielsen, Jens Høiriis

    2008-01-01

    Beta cell mass, at any given time, is governed by cell differentiation, neogenesis, increased or decreased cell size (cell hypertrophy or atrophy), cell death (apoptosis), and beta cell proliferation. Nutrients, hormones and growth factors coupled with their signalling intermediates have been...... suggested to play a role in beta cell mass regulation. In addition, genetic mouse model studies have indicated that cyclins and cyclin-dependent kinases that determine cell cycle progression are involved in beta cell replication, and more recently, menin in association with cyclin-dependent kinase...... inhibitors has been demonstrated to be important in beta cell growth. In this review, we consider and highlight some aspects of cell cycle regulation in relation to beta cell replication. The role of cell cycle regulation in beta cell replication is mostly from studies in rodent models, but whether...

  7. Small cell glioblastoma or small cell carcinoma

    DEFF Research Database (Denmark)

    Hilbrandt, Christine; Sathyadas, Sathya; Dahlrot, Rikke H

    2013-01-01

    was admitted to the hospital with left-sided loss of motor function. A MRI revealed a 6 cm tumor in the right temporoparietal area. The histology was consistent with both glioblastoma multiforme (GBM) and small cell lung carcinoma (SCLC) but IHC was suggestive of a SCLC metastasis. PET-CT revealed...

  8. Wnt-Dependent Control of Cell Polarity in Cultured Cells.

    Science.gov (United States)

    Runkle, Kristin B; Witze, Eric S

    2016-01-01

    The secreted ligand Wnt5a regulates cell polarity and polarized cell movement during development by signaling through the poorly defined noncanonical Wnt pathway. Cell polarity regulates most aspects of cell behavior including the organization of apical/basolateral membrane domains of epithelial cells, polarized cell divisions along a directional plane, and front rear polarity during cell migration. These characteristics of cell polarity allow coordinated cell movements required for tissue formation and organogenesis during embryonic development. Genetic model organisms have been used to identify multiple signaling pathways including Wnt5a that are required to establish cell polarity and regulate polarized cell behavior. However, the downstream signaling events that regulate these complex cellular processes are still poorly understood. The methods below describe assays to study Wnt5a-induced cell polarity in cultured cells, which may facilitate our understanding of these complex signaling pathways.

  9. Single-cell sequencing in stem cell biology.

    Science.gov (United States)

    Wen, Lu; Tang, Fuchou

    2016-04-15

    Cell-to-cell variation and heterogeneity are fundamental and intrinsic characteristics of stem cell populations, but these differences are masked when bulk cells are used for omic analysis. Single-cell sequencing technologies serve as powerful tools to dissect cellular heterogeneity comprehensively and to identify distinct phenotypic cell types, even within a 'homogeneous' stem cell population. These technologies, including single-cell genome, epigenome, and transcriptome sequencing technologies, have been developing rapidly in recent years. The application of these methods to different types of stem cells, including pluripotent stem cells and tissue-specific stem cells, has led to exciting new findings in the stem cell field. In this review, we discuss the recent progress as well as future perspectives in the methodologies and applications of single-cell omic sequencing technologies.

  10. Molecular mechanisms controlling the cell cycle in embryonic stem cells.

    Science.gov (United States)

    Abdelalim, Essam M

    2013-12-01

    Embryonic stem (ES) cells are originated from the inner cell mass of a blastocyst stage embryo. They can proliferate indefinitely, maintain an undifferentiated state (self-renewal), and differentiate into any cell type (pluripotency). ES cells have an unusual cell cycle structure, consists mainly of S phase cells, a short G1 phase and absence of G1/S checkpoint. Cell division and cell cycle progression are controlled by mechanisms ensuring the accurate transmission of genetic information from generation to generation. Therefore, control of cell cycle is a complicated process, involving several signaling pathways. Although great progress has been made on the molecular mechanisms involved in the regulation of ES cell cycle, many regulatory mechanisms remain unknown. This review summarizes the current knowledge about the molecular mechanisms regulating the cell cycle of ES cells and describes the relationship existing between cell cycle progression and the self-renewal.

  11. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...... activation through coculture with T cells activated by anti-T-cell receptor or anti-CD3 antibodies suggest that cellular interaction with T cells, independent of antigen presentation or lymphokine secretion, induces or triggers B cells to become responsive to T-derived lymphokines, and that this may...

  12. Stem cell regulation: Implications when differentiated cells regulate symmetric stem cell division.

    Science.gov (United States)

    Høyem, Marte Rørvik; Måløy, Frode; Jakobsen, Per; Brandsdal, Bjørn Olav

    2015-09-07

    We use a mathematical model to show that if symmetric stem cell division is regulated by differentiated cells, then changes in the population dynamics of the differentiated cells can lead to changes in the population dynamics of the stem cells. More precisely, the relative fitness of the stem cells can be affected by modifying the death rate of the differentiated cells. This result is interesting because stem cells are less sensitive than differentiated cells to environmental factors, such as medical therapy. Our result implies that stem cells can be manipulated indirectly by medical treatments that target the differentiated cells. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  13. Dedifferentiated adipocyte-derived progeny cells (DFAT cells): Potential stem cells of adipose tissue.

    Science.gov (United States)

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J; Rasmussen, Theodore P; Bergen, Werner G; Dodson, Michael V

    2013-07-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, engineering and disease treatment. The dedifferentiation of mature adipocytes, the multipotent capacity of DFAT cells and comparisons and contrasts with mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPS) are discussed in this review.

  14. [Acute plasma cell leukemia].

    Science.gov (United States)

    Monsalbe, V; Domíngues, C; Roa, I; Busel, D; González, S

    1989-01-01

    Plasma Cell Leukemia is a very rare form of plasmocytic dyscrasia, whose clinical and pathological characteristics warrant its recognition as a distinct subentity. We report the case of a 60 years old man who presented a rapidly fatal acute plasma cell leukemia, with multiple osteolytic lesions, hipercalcemia, renal and cardiac failure.

  15. T-cell costimulation

    DEFF Research Database (Denmark)

    Owens, T

    1996-01-01

    The CD40L molecule expressed by CD4+ regulatory T lymphocytes is known to deliver signals that activate B cells and macrophages. It now appears that CD40L regulates T cells themselves, during both their development and their participation in adaptive immune responses....

  16. Cell-Assisted Lipotransfer

    DEFF Research Database (Denmark)

    Toyserkani, Navid Mohamadpour; Quaade, Marlene Louise; Sørensen, Jens Ahm

    2016-01-01

    -derived stromal cells (ASCs) to enrich the fat graft, a procedure termed cell-assisted lipotransfer (CAL). The aim of this review was to systematically review the current preclinical and clinical evidence for the efficacy of CAL compared with conventional lipotransfer. MATERIALS AND METHODS: A systematic search...

  17. Modeling: driving fuel cells

    Directory of Open Access Journals (Sweden)

    Michael Francis

    2002-05-01

    Fuel cells were invented in 1839 by Sir William Grove, a Welsh judge and gentleman scientist, as a result of his experiments on the electrolysis of water. To put it simply, fuel cells are electrochemical devices that take hydrogen gas from fuel, combine it with oxygen from the air, and generate electricity and heat, with water as the only by-product.

  18. Cystic Granular Cell Ameloblastoma

    OpenAIRE

    Thillaikarasi, Rathnavel; Balaji, Jayaram; Gupta, Bhawna; Ilayarja, Vadivel; Vani, Nandimandalam Venkata; Vidula, Balachander; Saravanan, Balasubramaniam; Ponniah, Irulandy

    2010-01-01

    Ameloblastoma is a locally aggressive benign epithelial odontogenic tumor, while unicystic ameloblastoma is a relatively less aggressive variant. Although rare in unicystic or cystic ameloblastoma, granular cell change in ameloblastoma is a recognized phenomenon. The purpose of the present article is to report a case of cystic granular cell ameloblastoma in 34-year old female.

  19. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to participate…

  20. Programmed cell death

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1995-12-31

    The purpose of this conference to provide a multidisciplinary forum for exchange of state-of-the-art information on the role programmed cell death plays in normal development and homeostasis of many organisms. This volume contains abstracts of papers in the following areas: invertebrate development; immunology/neurology; bcl-2 family; biochemistry; programmed cell death in viruses; oncogenesis; vertebrate development; and diseases.

  1. Mesangial cell biology

    Energy Technology Data Exchange (ETDEWEB)

    Abboud, Hanna E., E-mail: Abboud@uthscsa.edu

    2012-05-15

    Mesangial cells originate from the metanephric mesenchyme and maintain structural integrity of the glomerular microvascular bed and mesangial matrix homeostasis. In response to metabolic, immunologic or hemodynamic injury, these cells undergo apoptosis or acquire an activated phenotype and undergo hypertrophy, proliferation with excessive production of matrix proteins, growth factors, chemokines and cytokines. These soluble factors exert autocrine and paracrine effects on the cells or on other glomerular cells, respectively. MCs are primary targets of immune-mediated glomerular diseases such as IGA nephropathy or metabolic diseases such as diabetes. MCs may also respond to injury that primarily involves podocytes and endothelial cells or to structural and genetic abnormalities of the glomerular basement membrane. Signal transduction and oxidant stress pathways are activated in MCs and likely represent integrated input from multiple mediators. Such responses are convenient targets for therapeutic intervention. Studies in cultured MCs should be supplemented with in vivo studies as well as examination of freshly isolated cells from normal and diseases glomeruli. In addition to ex vivo morphologic studies in kidney cortex, cells should be studied in their natural environment, isolated glomeruli or even tissue slices. Identification of a specific marker of MCs should help genetic manipulation as well as selective therapeutic targeting of these cells. Identification of biological responses of MCs that are not mediated by the renin–angiotensin system should help development of novel and effective therapeutic strategies to treat diseases characterized by MC pathology.

  2. Tumor cell metabolism

    Science.gov (United States)

    Romero-Garcia, Susana; Lopez-Gonzalez, Jose Sullivan; B´ez-Viveros, José Luis; Aguilar-Cazares, Dolores

    2011-01-01

    Cancer is a genetic disease that is caused by mutations in oncogenes, tumor suppressor genes and stability genes. The fact that the metabolism of tumor cells is altered has been known for many years. However, the mechanisms and consequences of metabolic reprogramming have just begun to be understood. In this review, an integral view of tumor cell metabolism is presented, showing how metabolic pathways are reprogrammed to satisfy tumor cell proliferation and survival requirements. In tumor cells, glycolysis is strongly enhanced to fulfill the high ATP demands of these cells; glucose carbons are the main building blocks in fatty acid and nucleotide biosynthesis. Glutaminolysis is also increased to satisfy NADPH regeneration, whereas glutamine carbons replenish the Krebs cycle, which produces metabolites that are constantly used for macromolecular biosynthesis. A characteristic feature of the tumor microenvironment is acidosis, which results from the local increase in lactic acid production by tumor cells. This phenomenon is attributed to the carbons from glutamine and glucose, which are also used for lactic acid production. Lactic acidosis also directs the metabolic reprogramming of tumor cells and serves as an additional selective pressure. Finally, we also discuss the role of mitochondria in supporting tumor cell metabolism. PMID:22057267

  3. Transparent solar cell module

    Science.gov (United States)

    Antonides, G. J.; Dillard, P. A.; Fritz, W. M.; Lott, D. P.

    1979-01-01

    Modified solar cell module uses high transmission glass and adhesives, and heat dissipation to boost power per unit area by 25% (9.84% efficiency based on cell area at 60 C and 100 mW/sq cm flux). Design is suited for automatic production and is potentially more cost effective.

  4. Sickle Cell Trait

    Science.gov (United States)

    ... Websites About Us Information For… Media Policy Makers Sickle Cell Trait Language: English (US) Español (Spanish) Recommend on Facebook Tweet Share Compartir Get Screened for Sickle Cell Trait Did you know there’s more than one way ...

  5. Toward sustainable fuel cells

    DEFF Research Database (Denmark)

    Stephens, Ifan; Rossmeisl, Jan; Chorkendorff, Ib

    2016-01-01

    to a regular gasoline car. However, current fuel cells require 0.25 g of platinum (Pt) per kilowatt of power (2) as catalysts to drive the electrode reactions. If the entire global annual production of Pt were devoted to fuel cell vehicles, fewer than 10 million vehicles could be produced each year, a mere 10...

  6. MICROBIAL FUEL CELL

    DEFF Research Database (Denmark)

    2008-01-01

    A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent...

  7. Stem cells in dermatology.

    Science.gov (United States)

    Ogliari, Karolyn Sassi; Marinowic, Daniel; Brum, Dario Eduardo; Loth, Fabrizio

    2014-01-01

    Preclinical and clinical research have shown that stem cell therapy could be a promising therapeutic option for many diseases in which current medical treatments do not achieve satisfying results or cure. This article describes stem cells sources and their therapeutic applications in dermatology today.

  8. Biosensors for Cell Analysis.

    Science.gov (United States)

    Zhou, Qing; Son, Kyungjin; Liu, Ying; Revzin, Alexander

    2015-01-01

    Biosensors first appeared several decades ago to address the need for monitoring physiological parameters such as oxygen or glucose in biological fluids such as blood. More recently, a new wave of biosensors has emerged in order to provide more nuanced and granular information about the composition and function of living cells. Such biosensors exist at the confluence of technology and medicine and often strive to connect cell phenotype or function to physiological or pathophysiological processes. Our review aims to describe some of the key technological aspects of biosensors being developed for cell analysis. The technological aspects covered in our review include biorecognition elements used for biosensor construction, methods for integrating cells with biosensors, approaches to single-cell analysis, and the use of nanostructured biosensors for cell analysis. Our hope is that the spectrum of possibilities for cell analysis described in this review may pique the interest of biomedical scientists and engineers and may spur new collaborations in the area of using biosensors for cell analysis.

  9. Fuel cells: Operating flexibly

    Science.gov (United States)

    Lee, Young Moo

    2016-09-01

    Fuel cells typically function well only in rather limited temperature and humidity ranges. Now, a proton exchange membrane consisting of ion pair complexes is shown to enable improved fuel cell performance under a wide range of conditions that are unattainable with conventional approaches.

  10. Electrochemical cell stack assembly

    Science.gov (United States)

    Jacobson, Craig P.; Visco, Steven J.; De Jonghe, Lutgard C.

    2010-06-22

    Multiple stacks of tubular electrochemical cells having a dense electrolyte disposed between an anode and a cathode preferably deposited as thin films arranged in parallel on stamped conductive interconnect sheets or ferrules. The stack allows one or more electrochemical cell to malfunction without disabling the entire stack. Stack efficiency is enhanced through simplified gas manifolding, gas recycling, reduced operating temperature and improved heat distribution.

  11. Ghost cell odontogenic carcinoma.

    NARCIS (Netherlands)

    Nazaretian, S.P.; Schenberg, M.E.; Simpson, I.; Slootweg, P.J.

    2007-01-01

    Ghost cell odontogenic carcinoma (GCOC) is the malignant counterpart of calcifying cystic odontogenic tumour and dentinogenic ghost cell tumour. This is the case of a middle-aged male who presented with a slow-growing maxillary tumour. He was asymptomatic until pain symptoms developed prior to initi

  12. Tetraspanins in Mast Cells

    Directory of Open Access Journals (Sweden)

    Martin eKöberle

    2012-05-01

    Full Text Available Mast cells are key mediators of the immune system, most prominently known for their role in eliciting harmful allergic reactions. Mast cell mediator release (e. g. by degranulation is triggered by Fc{epsilon}RI recognition of antigen – IgE complexes. Until today no therapeutic targeting of this and other mast cell activation pathways is established. Among possible new candidates there are tetraspanins that have been described on mast cells already several years ago.Tetraspanins are transmembrane proteins acting as scaffolds, mediating local clustering of their interaction partners and thus amplify their activities. More recently, tetraspanins were also found to exert intrinsic receptor functions. Tetraspanins have been found to be crucial components of fundamental biological processes like cell motility and adhesion. In immune cells, they not only boost the effectiveness of antigen presentation by clustering MHC molecules, they are also key players in all kinds of degranulation events and immune receptor clustering. This review focuses on the contribution of tetraspanins clustered with Fc{epsilon}RI or residing in granule membranes to classical mast cells functions but also undertakes an outlook on the possible contribution of tetraspanins to newly described mast cell functions and discusses possible drugging strategies.

  13. Ghrelin and cell differentiation

    Institute of Scientific and Technical Information of China (English)

    Geyang Xu; Yin Li; Wenjiao An; Weizhen Zhang

    2008-01-01

    Ghrelin, an endogenous ligand for the growth hormone secretagogue receptor, is a gastric hormone that has been found to have a wide variety of biological functions. This review summarizes our current understanding of the effects of ghrelin on cell differentiation and tissue development, with an emphasis on the lineage determination of mesenchymal stem cells.

  14. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to…

  15. PLATINUM AND FUEL CELLS

    Science.gov (United States)

    Platinum requirements for fuel cell vehicles (FCVS) have been identified as a concern and possible problem with FCV market penetration. Platinum is a necessary component of the electrodes of fuel cell engines that power the vehicles. The platinum is deposited on porous electrodes...

  16. Cell Phones for Education

    Science.gov (United States)

    Roberson, James H.; Hagevik, Rita A.

    2008-01-01

    Cell phones are fast becoming an integral part of students' everyday lives. They are regarded as important companions and tools for personal expression. School-age children are integrating the cell phone as such, and thus placing a high value on them. Educators endeavor to instill in students a high value for education, but often meet with…

  17. "Angular" plasma cell cheilitis.

    Science.gov (United States)

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida, Hiram Larangeira; Lorencette, Nádia Aparecida; Netto, José Fillus

    2014-03-17

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  18. "Angular" plasma cell cheilitis

    OpenAIRE

    da Cunha Filho, Roberto Rheingantz; Tochetto, Lucas Baldissera; Tochetto, Bruno Baldissera; de Almeida Jr, Hiram Larangeira; Lorencette, Nadia Aparecida; Netto, Jose Fillus

    2014-01-01

    Plasma cell cheilitis is an extremely rare disease, characterized by erythematous-violaceous, ulcerated and asymptomatic plaques, which evolve slowly. The histological characteristics include dermal infiltrate composed of mature plasmocytes. We report a case of Plasma cell angular cheilitis in a 58-year-old male, localized in the lateral oral commissure.

  19. Cell fusions in mammals

    DEFF Research Database (Denmark)

    Larsson, Lars-Inge; Bjerregaard, Bolette; Talts, Jan Fredrik

    2008-01-01

    Cell fusions are important to fertilization, placentation, development of skeletal muscle and bone, calcium homeostasis and the immune defense system. Additionally, cell fusions participate in tissue repair and may be important to cancer development and progression. A large number of factors appe...

  20. NCAM regulates cell motility.

    Science.gov (United States)

    Prag, Søren; Lepekhin, Eugene A; Kolkova, Kateryna; Hartmann-Petersen, Rasmus; Kawa, Anna; Walmod, Peter S; Belman, Vadym; Gallagher, Helen C; Berezin, Vladimir; Bock, Elisabeth; Pedersen, Nina

    2002-01-15

    Cell migration is required during development of the nervous system. The regulatory mechanisms for this process, however, are poorly elucidated. We show here that expression of or exposure to the neural cell adhesion molecule (NCAM) strongly affected the motile behaviour of glioma cells independently of homophilic NCAM interactions. Expression of the transmembrane 140 kDa isoform of NCAM (NCAM-140) caused a significant reduction in cellular motility, probably through interference with factors regulating cellular attachment, as NCAM-140-expressing cells exhibited a decreased attachment to a fibronectin substratum compared with NCAM-negative cells. Ectopic expression of the cytoplasmic part of NCAM-140 also inhibited cell motility, presumably via the non-receptor tyrosine kinase p59(fyn) with which NCAM-140 interacts. Furthermore, we showed that the extracellular part of NCAM acted as a paracrine inhibitor of NCAM-negative cell locomotion through a heterophilic interaction with a cell-surface receptor. As we showed that the two N-terminal immunoglobulin modules of NCAM, which are known to bind to heparin, were responsible for this inhibition, we presume that this receptor is a heparan sulfate proteoglycan. A model for the inhibitory effect of NCAM is proposed, which involves competition between NCAM and extracellular components for the binding to membrane-associated heparan sulfate proteoglycan.

  1. cell tumours of childhood

    African Journals Online (AJOL)

    neuron-specific-enolase, vimentin and neurofilament us- .... ated on a 4-point scale based on the number of positive cells: Negative staining (—) = no tumour cell stained. Minimal .... the same laboratory, have been shown previously to be.

  2. The Constitution by Cell

    Science.gov (United States)

    Greenhut, Stephanie; Jones, Megan

    2010-01-01

    On their visit to the National Archives Experience in Washington, D.C., students in Jenni Ashley and Gay Brock's U.S. history classes at the Potomac School in McLean, Virginia, participated in a pilot program called "The Constitution by Cell." Armed with their cell phones, a basic understanding of the Constitution, and a willingness to…

  3. Retinal stem cells and potential cell transplantation treatments.

    Science.gov (United States)

    Lin, Tai-Chi; Hsu, Chih-Chien; Chien, Ke-Hung; Hung, Kuo-Hsuan; Peng, Chi-Hsien; Chen, Shih-Jen

    2014-11-01

    The retina, histologically composed of ten delicate layers, is responsible for light perception and relaying electrochemical signals to the secondary neurons and visual cortex. Retinal disease is one of the leading clinical causes of severe vision loss, including age-related macular degeneration, Stargardt's disease, and retinitis pigmentosa. As a result of the discovery of various somatic stem cells, advances in exploring the identities of embryonic stem cells, and the development of induced pluripotent stem cells, cell transplantation treatment for retinal diseases is currently attracting much attention. The sources of stem cells for retinal regeneration include endogenous retinal stem cells (e.g., neuronal stem cells, Müller cells, and retinal stem cells from the ciliary marginal zone) and exogenous stem cells (e.g., bone mesenchymal stem cells, adipose-derived stem cells, embryonic stem cells, and induced pluripotent stem cells). The success of cell transplantation treatment depends mainly on the cell source, the timing of cell harvesting, the protocol of cell induction/transplantation, and the microenvironment of the recipient's retina. This review summarizes the different sources of stem cells for regeneration treatment in retinal diseases and surveys the more recent achievements in animal studies and clinical trials. Future directions and challenges in stem cell transplantation are also discussed.

  4. Transition of mesenchymal stem/stromal cells to endothelial cells

    NARCIS (Netherlands)

    M. Crisan (Mihaela)

    2013-01-01

    textabstractMesenchymal stem/stromal cells (MSCs) are heterogeneous. A fraction of these cells constitute multipotent cells that can self-renew and mainly give rise to mesodermal lineage cells such as adipocytes, osteocytes and chondrocytes. The ability of MSCs to differentiate into endothelial cell

  5. Induction of embryonic stem cells to hematopoietic cells in vitro

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to get hematopoietic cells from embryonic stem (ES) cells and to study development mechanisms of hematopoietic cells, the method of inducing embryonic stem cells to hematopoietic cells was explored by differenciating mouse ES cells and human embryonic cells in three stages. The differentiated cells were identified by flow cytometry, immunohistochemistry and Wright's staining. The results showed that embryoid bodies (EBs) could form when ES cells were cultured in the medium with 2-mercaptoethanol (2-ME). However, cytokines, such as stem cell factor (SCF), thrombopoietin (TPO), interleukin-3 (IL-3), interleukin-6 (IL-6), erythropoietin (EPO) and granular colony stimulating factor (G-CSF), were not helpful for forming EBs. SCF, TPO and embryonic cell conditional medium were useful for the differentiation of mouse EBs to hematopoietic progenitors. Eighty-six percent of these cells were CD34+ after 6-d culture. Hematopoietic progenitors differentiated to B lymphocytes when they were cocultured with primary bone marrow stroma cells in the DMEM medium with SCF and IL-6. 14 d later, most of the cells were CD34-CD38+. Wright's staining and immunohistochemistry showed that 80% of these cells were plasma-like morphologically and immunoglubolin positive. The study of hematopoietic cells from human embryonic cells showed that human embryonic cell differentiation was very similar to that of mouse ES cells. They could form EBs in the first stage and the CD34 positive cells account for about 48.5% in the second stage.

  6. Mast cells and inflammation.

    Science.gov (United States)

    Frenzel, Laurent; Hermine, Olivier

    2013-03-01

    The prominent role for mast cells in the inflammatory response has been increasingly well documented in recent years. Mast cells not only contribute to maintain homeostasis via degranulation and to generate IgE-mediated allergic reactions, but also sit at a major crossroads for both innate and adaptive immune responses. The part played by mast cells in chronic inflammatory diseases such as rheumatoid arthritis and multiple sclerosis identifies mast cells as a valuable treatment target in these diseases. Tyrosine-kinase inhibitors targeting the c-Kit mast cell receptor have been found effective in treating rheumatoid arthritis, asthma, and multiple sclerosis. When used in combination with other available drugs, tyrosine-kinase inhibitors may improve the therapeutic management of these diseases.

  7. Mast cell leukemia.

    Science.gov (United States)

    Georgin-Lavialle, Sophie; Lhermitte, Ludovic; Dubreuil, Patrice; Chandesris, Marie-Olivia; Hermine, Olivier; Damaj, Gandhi

    2013-02-21

    Mast cell leukemia (MCL) is a very rare form of aggressive systemic mastocytosis accounting for mast cell activation-involvement of the liver, spleen, peritoneum, bones, and marrow-are frequent. Diagnosis is based on the presence of ≥ 20% atypical mast cells in the marrow or ≥ 10% in the blood; however, an aleukemic variant is frequently encountered in which the number of circulating mast cells is < 10%. The common phenotypic features of pathologic mast cells encountered in most forms of mastocytosis are unreliable in MCL. Unexpectedly, non-KIT D816V mutations are frequent and therefore, complete gene sequencing is necessary. Therapy usually fails and the median survival time is < 6 months. The role of combination therapies and bone marrow transplantation needs further investigation.

  8. Dynamics of cell orientation

    Science.gov (United States)

    de, Rumi; Zemel, Assaf; Safran, Samuel A.

    2007-09-01

    Many physiological processes depend on the response of biological cells to mechanical forces generated by the contractile activity of the cell or by external stresses. Using a simple theoretical model that includes the forces due to both the mechanosensitivity of cells and the elasticity of the matrix, we predict the dynamics and orientation of cells in both the absence and presence of applied stresses. The model predicts many features observed in measurements of cellular forces and orientation including the increase with time of the cellular forces in the absence of applied stress and the consequent decrease of the force in the presence of quasi-static stresses. We also explain the puzzling observation of parallel alignment of cells for static and quasi-static stresses and of nearly perpendicular alignment for dynamically varying stresses. In addition, we predict the response of the cellular orientation to a sinusoidally varying applied stress as a function of frequency.

  9. Physics of adherent cells

    Science.gov (United States)

    Schwarz, Ulrich S.; Safran, Samuel A.

    2013-07-01

    One of the most unique physical features of cell adhesion to external surfaces is the active generation of mechanical force at the cell-material interface. This includes pulling forces generated by contractile polymer bundles and networks, and pushing forces generated by the polymerization of polymer networks. These forces are transmitted to the substrate mainly by focal adhesions, which are large, yet highly dynamic adhesion clusters. Tissue cells use these forces to sense the physical properties of their environment and to communicate with each other. The effect of forces is intricately linked to the material properties of cells and their physical environment. Here a review is given of recent progress in our understanding of the role of forces in cell adhesion from the viewpoint of theoretical soft matter physics and in close relation to the relevant experiments.

  10. Cell Radiation Experiment System

    Science.gov (United States)

    Morrison, Dennis R.

    2010-01-01

    The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

  11. Cell-Size Control

    Science.gov (United States)

    Amodeo, Amanda A.; Skotheim, Jan M.

    2015-01-01

    Cells of a given type maintain a characteristic cell size to function efficiently in their ecological or organismal context. They achieve this through the regulation of growth rates or by actively sensing size and coupling this signal to cell division. We focus this review on potential size-sensing mechanisms, including geometric, external cue, and titration mechanisms. Mechanisms that titrate proteins against DNA are of particular interest because they are consistent with the robust correlation of DNA content and cell size. We review the literature, which suggests that titration mechanisms may underlie cell-size sensing in Xenopus embryos, budding yeast, and Escherichia coli, whereas alternative mechanisms may function in fission yeast. PMID:26254313

  12. Cell manipulation in microfluidics.

    Science.gov (United States)

    Yun, Hoyoung; Kim, Kisoo; Lee, Won Gu

    2013-06-01

    Recent advances in the lab-on-a-chip field in association with nano/microfluidics have been made for new applications and functionalities to the fields of molecular biology, genetic analysis and proteomics, enabling the expansion of the cell biology field. Specifically, microfluidics has provided promising tools for enhancing cell biological research, since it has the ability to precisely control the cellular environment, to easily mimic heterogeneous cellular environment by multiplexing, and to analyze sub-cellular information by high-contents screening assays at the single-cell level. Various cell manipulation techniques in microfluidics have been developed in accordance with specific objectives and applications. In this review, we examine the latest achievements of cell manipulation techniques in microfluidics by categorizing externally applied forces for manipulation: (i) optical, (ii) magnetic, (iii) electrical, (iv) mechanical and (v) other manipulations. We furthermore focus on history where the manipulation techniques originate and also discuss future perspectives with key examples where available.

  13. Cell Control Engineering

    DEFF Research Database (Denmark)

    Lynggaard, Hans Jørgen Birk; Alting, Leo

    1996-01-01

    The engineering process of creating cell control systems is described, and a Cell Control Engineering (CCE) concept is defined. The purpose is to assist people, representing different disciplines in the organisation, to implement cell controllers by addressing the complexity of having many systems...... in physically and logically different and changing manufacturing environments. The defined CCE concept combines state-of-the-art of commercially available enabling technologies for automation system software development, generic cell control models and guidelines for the complete engineering process....... It facilitates the understanding of the task and structure of cell controllers and uses this knowledge directly in the implementation of the system. By applying generic models CCE facilitates reuse of software components and maintenance of applications. In many enterprises, software makes up an increasing part...

  14. HTPEM Fuel Cell Impedance

    DEFF Research Database (Denmark)

    Vang, Jakob Rabjerg

    As part of the process to create a fossil free Denmark by 2050, there is a need for the development of new energy technologies with higher efficiencies than the current technologies. Fuel cells, that can generate electricity at higher efficiencies than conventional combustion engines, can...... potentially play an important role in the energy system of the future. One of the fuel cell technologies, that receives much attention from the Danish scientific community is high temperature proton exchange membrane (HTPEM) fuel cells based on polybenzimidazole (PBI) with phosphoric acid as proton conductor....... This type of fuel cell operates at higher temperature than comparable fuel cell types and they distinguish themselves by high CO tolerance. Platinum based catalysts have their efficiency reduced by CO and the effect is more pronounced at low temperature. This Ph.D. Thesis investigates this type of fuel...

  15. Solid electrolytic fuel cell

    Energy Technology Data Exchange (ETDEWEB)

    Sakai, Masayasu; Yamauchi, Yasuhiro; Kamisaka, Mitsuo; Notomi, Kei.

    1989-04-21

    Concerning a solid electrolytic fuel cell with a gas permeable substrate pipe, a fuel electrode installed on this substrate pipe and an air electrode which is laminated on this fuel electrode with the electrolyte in between, the existing fuel cell of this kind uses crystals of CaMnO3, etc. for the material of the air electrode, but its electric resistance is big and in order to avert this, it is necessary to make the film thickness of the air electrode big. However, in such a case, the entry of the air into its inside worsens and the cell performance cannot develop satisfactorily. In view of the above, in order to obtain a high performance solid electrolytic fuel cell which can improve electric conductivity without damaging diffusion rate of the air, this invention proposes with regard to the aforementioned solid electrolytic fuel cell to install a heat resistant and conductive member inside the above air electrode. 6 figs.

  16. Metallization of bacteria cells

    Institute of Scientific and Technical Information of China (English)

    黎向锋; 李雅芹; 蔡军; 张德远

    2003-01-01

    Bacteria cells with different standard shapes are well suited for use as templates for the fabrication of magnetic and electrically conductive microstructures. In this paper, metallization of bacteria cells is demonstrated by an electroless deposition technique of nickel-phosphorus initiated by colloid palladium-tin catalyst on the surfaces of Citeromyces matritensis and Bacillus cereus. The activated and metallized bacteria cells have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). Results showed that both Citeromyces matritensis and Bacillus cereus had no deformation in shape after metallization; the metallized films deposited on the surfaces of bacteria cells are homogeneous in thickness and noncrystalline in phase structure. The kinetics of colloid palladium-tin solution and electroless plating on bacteria cells is discussed.

  17. Storing Blood Cells

    Science.gov (United States)

    1976-01-01

    The National Cancer Institute worked with Goddard Space Flight Center to propose a solution to the blood-cell freezing problem. White blood cells and bone marrow are stored for future use by leukemia patients as a result of Goddard and Jet Propulsion Laboratory expertise in electronics and cryogenics. White blood cell and bone marrow bank established using freezing unit. Freezing unit monitors temperature of cells themselves. Thermocouple placed against polyethylene container relays temperature signals to an electronic system which controls small heaters located outside container. Heaters allow liquid nitrogen to circulate at constant temperature and maintain consistent freezing rate. Ability to freeze, store, and thaw white cells and bone marrow without damage is important in leukemia treatment.

  18. Solar cell radiation handbook

    Science.gov (United States)

    Tada, H. Y.; Carter, J. R., Jr.; Anspaugh, B. E.; Downing, R. G.

    1982-01-01

    The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  19. Cell cycle regulation in human embryonic stem cells: links to adaptation to cell culture.

    Science.gov (United States)

    Barta, Tomas; Dolezalova, Dasa; Holubcova, Zuzana; Hampl, Ales

    2013-03-01

    Cell cycle represents not only a tightly orchestrated mechanism of cell replication and cell division but it also plays an important role in regulation of cell fate decision. Particularly in the context of pluripotent stem cells or multipotent progenitor cells, regulation of cell fate decision is of paramount importance. It has been shown that human embryonic stem cells (hESCs) show unique cell cycle characteristics, such as short doubling time due to abbreviated G1 phase; these properties change with the onset of differentiation. This review summarizes the current understanding of cell cycle regulation in hESCs. We discuss cell cycle properties as well as regulatory machinery governing cell cycle progression of undifferentiated hESCs. Additionally, we provide evidence that long-term culture of hESCs is accompanied by changes in cell cycle properties as well as configuration of several cell cycle regulatory molecules.

  20. Advances in stem cell research

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    @@In 1998, biologists Thomson and Gearhart successfully derived stem cells from human embryos. One year later, several researchers discovered that adult stem cells still retain the ability to be differentiated into unrelated types of cells. Advances in stem cell research open a promising direction for applied medical science. Moreover, it may also force scientists to reconsider the fundamental theory about how cells grow up. Stem cell research was considered by Science as the top of the ten breakthroughs of science of the year[1]. This paper gives a survey of recent advances in stem cell research. 1 Overview In the 1980s, embryonic stem cell and/or embryonic germ cell line (ES cell line, EG cell line) of multifarious mammalian animals, especially those of non-human pri-mates, had been established. In 1998, Thomson and Shamblott obtained ES, EG cell lines from human blasto-cysts and gonad ridges of early human embryos, respec-tively. Their research brought up an ethical debate about whether human embryos can be used as experimental materials. It was not appeased until 1999 when research-ers discovered that stem cells from adults still retain the ability to become different kinds of tissue cells. For in-stance, brain cells can become blood cells[2], and cells from bone marrow can become cells in liver. Scientists believe, for a long time, that cells can only be developed from early pluripotent embryo cells; the differentiation potential of stem cells from mature tissues is restricted to only one of the cell types of the tissue where stem cells are obtained. Recent stem cell researches, however, sub-verted the traditional view of stem cells. These discoveries made scientists speed ahead with the work on adult stem cells, hoping to discover whether their promise will rival that of ES cells.

  1. CCL22-specific T Cells

    DEFF Research Database (Denmark)

    Martinenaite, Evelina; Munir Ahmad, Shamaila; Hansen, Morten

    2016-01-01

    Tumor cells and tumor-infiltrating macrophages produce the chemokine CCL22, which attracts regulatory T cells (Tregs) into the tumor microenvironment, decreasing anticancer immunity. Here, we investigated the possibility of targeting CCL22-expressing cells by activating specific T cells. We...... analyzed the CCL22 protein signal sequence, identifying a human leukocyte antigen A2- (HLA-A2-) restricted peptide epitope, which we then used to stimulate peripheral blood mononuclear cells (PMBCs) to expand populations of CCL22-specific T cells in vitro. T cells recognizing an epitope derived from...... the signal-peptide of CCL22 will recognize CCL22-expressing cells even though CCL22 is secreted out of the cell. CCL22-specific T cells recognized and killed CCL22-expressing cancer cells. Furthermore, CCL22-specific T cells lysed acute monocytic leukemia cells in a CCL22 expression-dependent manner. Using...

  2. From Adult Bone Marrow Cells to Other Cell Lineages:Transdifferentiation or Cells Fusion

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    Recent studies have demonstrated that intravenous transplantation or local injection of bone marrow cells can induce unexpected changes of their fate. The results of these experiments showed that after transplantation or injecton, some of tissue specific somatic cells such as hepatocytes, skeleton, cardiac muscle cells and brain cells expressed the donor cell-specific genes, such as Y chromosome. There are two hypotheses that can explain this phenomenon. One is bone marrow stem cell transdifferentiation and the other is spontaneous cell fusion.

  3. Hilar mossy cell circuitry controlling dentate granule cell excitability

    Directory of Open Access Journals (Sweden)

    Seiichiro eJinde

    2013-02-01

    Full Text Available Glutamatergic hilar mossy cells of the dentate gyrus can either excite or inhibit distant granule cells, depending on whether their direct excitatory projections to granule cells or their projections to local inhibitory interneurons dominate. However, it remains controversial whether the net effect of mossy cell loss is granule cell excitation or inhibition. Clarifying this controversy has particular relevance to temporal lobe epilepsy, which is marked by dentate granule cell hyperexcitability and extensive loss of dentate hilar mossy cells. Two diametrically opposed hypotheses have been advanced to explain this granule cell hyperexcitability – the dormant basket cell and the irritable mossy cell hypotheses. The dormant basket cell hypothesis proposes that mossy cells normally exert a net inhibitory effect on granule cells and therefore their loss causes dentate granule cell hyperexcitability. The irritable mossy cell hypothesis takes the opposite view that mossy cells normally excite granule cells and that the surviving mossy cells in epilepsy increase their activity, causing granule cell excitation. The inability to eliminate mossy cells selectively has made it difficult to test these two opposing hypotheses. To this end, we developed a transgenic toxin-mediated, mossy cell-ablation mouse line. Using these mutants, we demonstrated that the extensive elimination of hilar mossy cells causes granule cell hyperexcitability, although the mossy cell loss observed appeared insufficient to cause clinical epilepsy. In this review, we focus on this topic and also suggest that different interneuron populations may mediate mossy cell-induced translamellar lateral inhibition and intralamellar recurrent inhibition. These unique local circuits in the dentate hilar region may be centrally involved in the functional organization of the dentate gyrus.

  4. Oscillating Cell Culture Bioreactor

    Science.gov (United States)

    Freed, Lisa E.; Cheng, Mingyu; Moretti, Matteo G.

    2010-01-01

    To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid

  5. Microfluidics for single cell analysis

    DEFF Research Database (Denmark)

    Jensen, Marie Pødenphant

    Isolation and manipulation of single cells have gained an increasing interest from researchers because of the heterogeneity of cells from the same cell culture. Single cell analysis can ensure a better understanding of differences between individual cells and potentially solve a variety of clinic...

  6. Many facets of stem cells

    Institute of Scientific and Technical Information of China (English)

    Jiarui Wu

    2011-01-01

    @@ Research area on stem cells is one of frontiers in biology.The collection of five research articles in this issue aims to cover timely developments in stem cell biology, ranging from generating and identifying stem cell line to manipulating stem cells, and from basic mechanism analysis to applied medical potential.These papers reflect the various research tasks in stem cell biology.

  7. Quantitative imaging of epithelial cell scattering identifies specific inhibitors of cell motility and cell-cell dissociation

    NARCIS (Netherlands)

    Loerke, D.; le Duc, Q.; Blonk, I.; Kerstens, A.; Spanjaard, E.; Machacek, M.; Danuser, G.; de Rooij, J.

    2012-01-01

    The scattering of cultured epithelial cells in response to hepatocyte growth factor (HGF) is a model system that recapitulates key features of metastatic cell behavior in vitro, including disruption of cell-cell adhesions and induction of cell migration. We have developed image analysis tools that

  8. Low White Blood Cell Count

    Science.gov (United States)

    Symptoms Low white blood cell count By Mayo Clinic Staff A low white blood cell count (leukopenia) is a decrease in disease-fighting cells ( ... a decrease in a certain type of white blood cell (neutrophil). The definition of low white blood cell ...

  9. Embryonic stem cells: testing the germ-cell theory.

    Science.gov (United States)

    Hochedlinger, Konrad

    2011-10-25

    The exact cellular origin of embryonic stem cells remains elusive. Now a new study provides compelling evidence that embryonic stem cells, established under conventional culture conditions, originate from a transient germ-cell state.

  10. Single-cell model of prokaryotic cell cycle.

    Science.gov (United States)

    Abner, Kristo; Aaviksaar, Tõnis; Adamberg, Kaarel; Vilu, Raivo

    2014-01-21

    One of the recognized prokaryotic cell cycle theories is Cooper-Helmstetter (CH) theory which relates start of DNA replication to particular (initiation) cell mass, cell growth and division. Different aspects of this theory have been extensively studied in the past. In the present study CH theory was applied at single cell level. Universal equations were derived for different cell parameters (cell mass and volume, surface area, DNA amount and content) depending on constructivist cell cycle parameters (unit mass, replication and division times, cell age, cell cycle duration) based on selected growth laws of cell mass (linear, exponential). The equations derived can be integrated into single-cell models for the analysis and design of bacterial cells. © 2013 Published by Elsevier Ltd.

  11. Immunology of Stem Cells and Cancer Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Xiao-Feng Yang

    2007-01-01

    The capacity of pluri-potent stem cells to repair the tissues in which stem cells reside holds great promise in development of novel cell replacement therapeutics for treating chronic and degenerative diseases. However,numerous reports show that stem cell therapy, even in an autologous setting, triggers lymphocyte infiltration and inflammation. Therefore, an important question to be answered is how the host immune system responds to engrafted autologous stem cells or allogeneous stem cells. In this brief review, we summarize the progress in several related areas in this field, including some of our data, in four sections: (1) immunogenicity of stem cells; (2)strategies to inhibit immune rejection to allograft stem cells; (3) immune responses to cancer stem cells; and (4)mesenchymal stem cells in immune regulation. Improvement of our understanding on these and other aspects of immune system-stem cell interplay would greatly facilitate the development of stem cell-based therapeutics for regenerative purposes.

  12. Llgl1 Connects Cell Polarity with Cell-Cell Adhesion in Embryonic Neural Stem Cells.

    Science.gov (United States)

    Jossin, Yves; Lee, Minhui; Klezovitch, Olga; Kon, Elif; Cossard, Alexia; Lien, Wen-Hui; Fernandez, Tania E; Cooper, Jonathan A; Vasioukhin, Valera

    2017-06-05

    Malformations of the cerebral cortex (MCCs) are devastating developmental disorders. We report here that mice with embryonic neural stem-cell-specific deletion of Llgl1 (Nestin-Cre/Llgl1(fl/fl)), a mammalian ortholog of the Drosophila cell polarity gene lgl, exhibit MCCs resembling severe periventricular heterotopia (PH). Immunohistochemical analyses and live cortical imaging of PH formation revealed that disruption of apical junctional complexes (AJCs) was responsible for PH in Nestin-Cre/Llgl1(fl/fl) brains. While it is well known that cell polarity proteins govern the formation of AJCs, the exact mechanisms remain unclear. We show that LLGL1 directly binds to and promotes internalization of N-cadherin, and N-cadherin/LLGL1 interaction is inhibited by atypical protein kinase C-mediated phosphorylation of LLGL1, restricting the accumulation of AJCs to the basolateral-apical boundary. Disruption of the N-cadherin-LLGL1 interaction during cortical development in vivo is sufficient for PH. These findings reveal a mechanism responsible for the physical and functional connection between cell polarity and cell-cell adhesion machineries in mammalian cells. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. Stretching cells with DEAs

    Science.gov (United States)

    Akbari, S.; Rosset, S.; Shea, H. R.

    2012-04-01

    Biological cells regulate their biochemical behavior in response to mechanical stress present in their organism. Most of the available cell cultures designed to study the effect of mechanical stimuli on cells are cm2 area, far too large to monitor single cell response or have a very low throughput. We have developed two sets of high throughput single cell stretcher devices based on dielectric elastomer microactuators to stretch groups of individual cells with various strain levels in a single experiment. The first device consists of an array of 100 μm x 200 μm actuators on a non-stretched PDMS membrane bonded to a Pyrex chip, showing up to 4.7% strain at the electric field of 96 V/μm. The second device contains an array of 100 μm x 100 μm actuators on a 160% uniaxially prestretched PDMS membrane suspended over a frame. 37% strain is recorded at the nominal electric field of 114 V/μm. The performance of these devices as a cell stretcher is assessed by comparing their static and dynamic behavior.

  14. Rethinking Guard Cell Metabolism.

    Science.gov (United States)

    Santelia, Diana; Lawson, Tracy

    2016-11-01

    Stomata control gaseous fluxes between the internal leaf air spaces and the external atmosphere and, therefore, play a pivotal role in regulating CO2 uptake for photosynthesis as well as water loss through transpiration. Guard cells, which flank the stomata, undergo adjustments in volume, resulting in changes in pore aperture. Stomatal opening is mediated by the complex regulation of ion transport and solute biosynthesis. Ion transport is exceptionally well understood, whereas our knowledge of guard cell metabolism remains limited, despite several decades of research. In this review, we evaluate the current literature on metabolism in guard cells, particularly the roles of starch, sucrose, and malate. We explore the possible origins of sucrose, including guard cell photosynthesis, and discuss new evidence that points to multiple processes and plasticity in guard cell metabolism that enable these cells to function effectively to maintain optimal stomatal aperture. We also discuss the new tools, techniques, and approaches available for further exploring and potentially manipulating guard cell metabolism to improve plant water use and productivity. © 2016 American Society of Plant Biologists. All Rights Reserved.

  15. Cell density monitoring and control of microencapsulated CHO cell cultures

    OpenAIRE

    Cole, Harriet Emma

    2015-01-01

    Though mammalian cells play a key role in the manufacturing of recombinant glycosylated proteins, cell cultures and productivity are limited by the lack of suitable systems to enable stable perfusion culture. Microencapsulation, or entrapping cells within a semi-permeable membrane, offers the potential to generate high cell density cultures and improve the productivity by mimicking the cells natural environment. However, the cells being secluded by the microcapsules membrane are difficult to ...

  16. Plasma cells negatively regulate the follicular helper T cell program

    OpenAIRE

    2010-01-01

    B lymphocytes differentiate into antibody-secreting cells under the antigen-specific control of follicular helper T (TFH) cells. Here, we demonstrate that isotype-switched plasma cells expressed MHCII, CD80 and CD86 and intracellular machinery required for antigen presentation. Antigen-specific plasma cells could access, process and present sufficient antigen in vivo to induce multiple TH cell functions. Importantly, antigen-primed plasma cells failed to induce interleukin 21 or Bcl-6 in naïv...

  17. Dedifferentiated fat cells: A cell source for regenerative medicine

    OpenAIRE

    Jumabay, Medet; Boström, Kristina I.

    2015-01-01

    The identification of an ideal cell source for tissue regeneration remains a challenge in the stem cell field. The ability of progeny cells to differentiate into other cell types is important for the processes of tissue reconstruction and tissue engineering and has clinical, biochemical or molecular implications. The adaptation of stem cells from adipose tissue for use in regenerative medicine has created a new role for adipocytes. Mature adipocytes can easily be isolated from adipose cell su...

  18. Single Cell Characterization of Prostate Cancer-Circulating Tumor Cells

    Science.gov (United States)

    2013-09-01

    al., 2010). In addition, there were a significant number of cell cycle and mitosis associated transcripts in the highly expressed gene set including...red blood cell lysis with 10 volumes of 16 PharmLyse (BD Biosciences) for 15 minutes at room temperature . Remaining cells were pelleted at 4uC for 15...processes (23%, GO:0008152) or the cell cycle (10%, GO:0007049), consistent with mitotically active cells (Fig. 4C). Cell cycle and mitosis associated

  19. Cell of Origin and Cancer Stem Cell Phenotype in Medulloblastomas

    Science.gov (United States)

    2015-07-01

    progenitor cells (NPCs) by expressing an activated form of Notch1 (N1ICD) or oncogenic PIK3CA (PIK3CA*) in the developing mouse cerebellum, using cell...resistance, pediatric cancer, brain tumor, Notch1, PIK3CA, cell of origin, molecular subtypes, neural stem cells, neural progenitor cells, tumor initiation...neural progenitor cells, tumor initiation. 3. ACCOMPLISHMENTS: Major goals of the project: The stated goals of this project are to: 1) test the

  20. Mesothelial cell differentiation into osteoblast- and adipocyte-like cells

    OpenAIRE

    Sally M Lansley; Searles, Richelle G.; Hoi, Aina; Thomas, Carla; Moneta, Helena; Herrick, Sarah E; Thompson, Philip J; Mark, Newman; Sterrett, Gregory F; Prêle, Cecilia M; Mutsaers, Steven E.

    2011-01-01

    Serosal pathologies including malignant mesothelioma (MM) can show features of osseous and/or cartilaginous differentiation although the mechanism for its formation is unknown. Mesothelial cells have the capacity to differentiate into cells with myofibroblast, smooth muscle and endothelial cell characteristics. Whether they can differentiate into other cell types is unclear. This study tests the hypothesis that mesothelial cells can differentiate into cell lineages of the embryonic mesoderm i...

  1. Cell Growth Enhancement

    Science.gov (United States)

    1992-01-01

    Exogene Corporation uses advanced technologies to enhance production of bio-processed substances like proteins, antibiotics and amino acids. Among them are genetic modification and a genetic switch. They originated in research for Jet Propulsion Laboratory. Extensive experiments in cell growth through production of hemoglobin to improve oxygen supply to cells were performed. By improving efficiency of oxygen use by cells, major operational expenses can be reduced. Greater product yields result in decreased raw material costs and more efficient use of equipment. A broad range of applications is cited.

  2. Quantum dot solar cells

    CERN Document Server

    Wu, Jiang

    2013-01-01

    The third generation of solar cells includes those based on semiconductor quantum dots. This sophisticated technology applies nanotechnology and quantum mechanics theory to enhance the performance of ordinary solar cells. Although a practical application of quantum dot solar cells has yet to be achieved, a large number of theoretical calculations and experimental studies have confirmed the potential for meeting the requirement for ultra-high conversion efficiency. In this book, high-profile scientists have contributed tutorial chapters that outline the methods used in and the results of variou

  3. Dye sensitized solar cells.

    Science.gov (United States)

    Wei, Di

    2010-03-16

    Dye sensitized solar cell (DSSC) is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO(2), ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  4. Dye Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Di Wei

    2010-03-01

    Full Text Available Dye sensitized solar cell (DSSC is the only solar cell that can offer both the flexibility and transparency. Its efficiency is comparable to amorphous silicon solar cells but with a much lower cost. This review not only covers the fundamentals of DSSC but also the related cutting-edge research and its development for industrial applications. Most recent research topics on DSSC, for example, applications of nanostructured TiO2, ZnO electrodes, ionic liquid electrolytes, carbon nanotubes, graphene and solid state DSSC have all been included and discussed.

  5. Materials for fuel cells

    Directory of Open Access Journals (Sweden)

    Sossina M Haile

    2003-03-01

    Full Text Available Because of their potential to reduce the environmental impact and geopolitical consequences of the use of fossil fuels, fuel cells have emerged as tantalizing alternatives to combustion engines. Like a combustion engine, a fuel cell uses some sort of chemical fuel as its energy source but, like a battery, the chemical energy is directly converted to electrical energy, without an often messy and relatively inefficient combustion step. In addition to high efficiency and low emissions, fuel cells are attractive for their modular and distributed nature, and zero noise pollution. They will also play an essential role in any future hydrogen fuel economy.

  6. Cardiac stem cell niches

    Directory of Open Access Journals (Sweden)

    Annarosa Leri

    2014-11-01

    Full Text Available The critical role that stem cell niches have in cardiac homeostasis and myocardial repair following injury is the focus of this review. Cardiac niches represent specialized microdomains where the quiescent and activated state of resident stem cells is regulated. Alterations in niche function with aging and cardiac diseases result in abnormal sites of cardiomyogenesis and inadequate myocyte formation. The relevance of Notch1 signaling, gap-junction formation, HIF-1α and metabolic state in the regulation of stem cell growth and differentiation within the cardiac niches are discussed.

  7. Giant Cell Fibroma

    OpenAIRE

    Tahere Nosratzehi; Lale Maleki

    2013-01-01

    Giant cell fibroma is a fibrous tumor which represents about 2 to 5% of all oral fibrotic proliferations. Compared to traumatic fibroma, giant (traumatic fibroma or irritation fibroma) cell fibroma occurs at a younger age. In about 60% of the cases the lesion is diagnosed within the first three decades of life and is slightly more in women. 50% of the cases is observed in the gum and will appear as a nodule with a papillary surface [1]. The giant cell fibroma is treated by conservative excisi...

  8. Congenital granular cell epulis.

    Science.gov (United States)

    Conrad, Rachel; Perez, Mia C N

    2014-01-01

    Congenital granular cell epulis is a rarely reported lesion of unknown histogenesis with a strong predilection for the maxillary alveolar ridge of newborn girls. Microscopically, it demonstrates nests of polygonal cells with granular cytoplasm, a prominent capillary network, and attenuated overlying squamous epithelium. The lesion lacks immunoreactivity for S-100, laminin, chromogranin, and most other markers except neuron-specific enolase and vimentin. Through careful observation of its unique clinical, histopathologic, and immunohistochemical features, this lesion can be distinguished from the more common adult granular cell tumor as well as other differential diagnoses.

  9. PLUTONIUM ELECTROREFINING CELLS

    Science.gov (United States)

    Mullins, L.J. Jr.; Leary, J.A.; Bjorklund, C.W.; Maraman, W.J.

    1963-07-16

    Electrorefining cells for obtaining 99.98% plutonium are described. The cells consist of an impure liquid plutonium anode, a molten PuCl/sub 3/-- alkali or alkaline earth metal chloanode, a molten PuCl/sub 3/-alkali or alkaline earth metal chloride electrolyte, and a nonreactive cathode, all being contained in nonreactive ceramic containers which separate anode from cathode by a short distance and define a gap for the collection of the purified liquid plutonium deposited on the cathode. Important features of these cells are the addition of stirrer blades on the anode lead and a large cathode surface to insure a low current density. (AEC)

  10. Conversion of primordial germ cells to pluripotent stem cells: methods for cell tracking and culture conditions.

    Science.gov (United States)

    Nagamatsu, Go; Suda, Toshio

    2013-01-01

    Primordial germ cells (PGCs) are unipotent cells committed to germ lineage: PGCs can only differentiate into gametes in vivo. However, upon fertilization, germ cells acquire the capacity to differentiate into all cell types in the body, including germ cells. Therefore, germ cells are thought to have the potential for pluripotency. PGCs can convert to pluripotent stem cells in vitro when cultured under specific conditions that include bFGF, LIF, and the membrane-bound form of SCF (mSCF). Here, the culture conditions which efficiently convert PGCs to pluripotent embryonic germ (EG) cells are described, as well as methods used for identifying pluripotent candidate cells during culture.

  11. Stem cell biology and cell transplantation therapy in the retina.

    Science.gov (United States)

    Osakada, Fumitaka; Hirami, Yasuhiko; Takahashi, Masayo

    2010-01-01

    Embryonic stem (ES) cells, which are derived from the inner cell mass of mammalian blastocyst stage embryos, have the ability to differentiate into any cell type in the body and to grow indefinitely while maintaining pluripotency. During development, cells undergo progressive and irreversible differentiation into specialized adult cell types. Remarkably, in spite of this restriction in potential, adult somatic cells can be reprogrammed and returned to the naive state of pluripotency found in the early embryo simply by forcing expression of a defined set of transcription factors. These induced pluripotent stem (iPS) cells are molecularly and functionally equivalent to ES cells and provide powerful in vitro models for development, disease, and drug screening, as well as material for cell replacement therapy. Since functional impairment results from cell loss in most central nervous system (CNS) diseases, recovery of lost cells is an important treatment strategy. Although adult neurogenesis occurs in restricted regions, the CNS has poor potential for regeneration to compensate for cell loss. Thus, cell transplantation into damaged or diseased CNS tissues is a promising approach to treating various neurodegenerative disorders. Transplantation of photoreceptors or retinal pigment epithelium cells derived from human ES cells can restore some visual function. Patient-specific iPS cells may lead to customized cell therapy. However, regeneration of retinal function will require a detailed understanding of eye development, visual system circuitry, and retinal degeneration pathology. Here, we review the current progress in retinal regeneration, focusing on the therapeutic potential of pluripotent stem cells.

  12. Embryonic stem cells: prospects for developmental biology and cell therapy.

    Science.gov (United States)

    Wobus, Anna M; Boheler, Kenneth R

    2005-04-01

    Stem cells represent natural units of embryonic development and tissue regeneration. Embryonic stem (ES) cells, in particular, possess a nearly unlimited self-renewal capacity and developmental potential to differentiate into virtually any cell type of an organism. Mouse ES cells, which are established as permanent cell lines from early embryos, can be regarded as a versatile biological system that has led to major advances in cell and developmental biology. Human ES cell lines, which have recently been derived, may additionally serve as an unlimited source of cells for regenerative medicine. Before therapeutic applications can be realized, important problems must be resolved. Ethical issues surround the derivation of human ES cells from in vitro fertilized blastocysts. Current techniques for directed differentiation into somatic cell populations remain inefficient and yield heterogeneous cell populations. Transplanted ES cell progeny may not function normally in organs, might retain tumorigenic potential, and could be rejected immunologically. The number of human ES cell lines available for research may also be insufficient to adequately determine their therapeutic potential. Recent molecular and cellular advances with mouse ES cells, however, portend the successful use of these cells in therapeutics. This review therefore focuses both on mouse and human ES cells with respect to in vitro propagation and differentiation as well as their use in basic cell and developmental biology and toxicology and presents prospects for human ES cells in tissue regeneration and transplantation.

  13. A novel cell subset:Interferon-producing killer dendritic cells

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Recent reports introduce a novel cell subset of DCs with antigenic phenotypes shared by both NK cells and B cells, but without surface markers of pDCs and T cells, appearing to be a chimera of NK cells and DCs, namely interferon-producing killer dendritic cells(IKDCs).IKDCs not only secret type I and type II interferons to recognize and kill tumor cells effectively, but also express MHC-II molecules to present antigens.Thus, IKDCs are considered as important immunosurveilance cells for tumors, providing a link between innate and adaptive immunity.

  14. Cell therapy for diabetes mellitus: an opportunity for stem cells?

    Science.gov (United States)

    Soria, B; Bedoya, F J; Tejedo, J R; Hmadcha, A; Ruiz-Salmerón, R; Lim, S; Martin, F

    2008-01-01

    Diabetes is a chronic disease characterized by a deficit in beta cell mass and a failure of glucose homeostasis. Both circumstances result in a variety of severe complications and an overall shortened life expectancy. Thus, diabetes represents an attractive candidate for cell therapy. Reversal of diabetes can be achieved through pancreas and islet transplantation, but shortage of donor organs has prompted an intensive search for alternative sources of beta cells. This achievement has stimulated the search for appropriate stem cell sources. Both embryonic and adult stem cells have been used to generate surrogate beta cells or otherwise restore beta cell functioning. In this regard, several studies have reported the generation of insulin-secreting cells from embryonic and adult stem cells that normalized blood glucose values when transplanted into diabetic animal models. Due to beta cell complexity, insulin-producing cells generated from stem cells do not possess all beta cell attributes. This indicates the need for further development of methods for differentiation and selection of completely functional beta cells. While these problems are overcome, diabetic patients may benefit from therapeutic strategies based on autologous stem cell therapies addressing late diabetic complications. In this article, we discuss the recent progress in the generation of insulin-producing cells from embryonic and adult stem cells, together with the challenges for the clinical use of diabetes stem cell therapy.

  15. Stem cells and transplant arteriosclerosis.

    Science.gov (United States)

    Xu, Qingbo

    2008-05-09

    Stem cells can differentiate into a variety of cells to replace dead cells or to repair damaged tissues. Recent evidence indicates that stem cells are involved in the pathogenesis of transplant arteriosclerosis, an alloimmune initiated vascular stenosis that often results in transplant organ failure. Although the pathogenesis of transplant arteriosclerosis is not yet fully understood, recent developments in stem cell research have suggested novel mechanisms of vascular remodeling in allografts. For example, stem cells derived from the recipient may repair damaged endothelial cells of arteries in transplant organs. Further evidence suggests that stem cells or endothelial progenitor cells may be released from both bone marrow and non-bone marrow tissues. Vascular stem cells appear to replenish cells that died in donor vessels. Concomitantly, stem/progenitor cells may also accumulate in the intima, where they differentiate into smooth muscle cells. However, several issues concerning the contribution of stem cells to the pathogenesis of transplant arteriosclerosis are controversial, eg, whether bone marrow-derived stem cells can differentiate into smooth muscle cells that form neointimal lesions of the vessel wall. This review summarizes recent research on the role of stem cells in transplant arteriosclerosis, discusses the mechanisms of stem cell homing and differentiation into mature endothelial and smooth muscle cells, and highlights the controversial issues in the field.

  16. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive

  17. Primitive human hematopoietic cells give rise to differentially specified daughter cells upon their initial cell division.

    NARCIS (Netherlands)

    Giebel, B.; Zhang, T.; Beckmann, J.; Spanholtz, J.; Wernet, P.; Ho, A.; Punzel, M.

    2006-01-01

    It is often predicted that stem cells divide asymmetrically, creating a daughter cell that maintains the stem-cell capacity, and 1 daughter cell committed to differentiation. While asymmetric stem-cell divisions have been proven to occur in model organisms (eg, in Drosophila), it remains illusive wh

  18. Perivascular cells for regenerative medicine

    NARCIS (Netherlands)

    M. Crisan (Mihaela); M. Corselli (Mirko); W.C. Chen (William); B. Péault (Bruno)

    2012-01-01

    textabstractMesenchymal stem/stromal cells (MSC) are currently the best candidate therapeutic cells for regenerative medicine related to osteoarticular, muscular, vascular and inflammatory diseases, although these cells remain heterogeneous and necessitate a better biological characterization. We an

  19. Stem Cell Transplants (For Teens)

    Science.gov (United States)

    ... Can I Help Someone Who's Being Bullied? Volunteering Stem Cell Transplants KidsHealth > For Teens > Stem Cell Transplants Print ... Does it Take to Recover? Coping What Are Stem Cells? As you probably remember from biology class, every ...

  20. What Causes Sickle Cell Disease?

    Science.gov (United States)

    ... inherited from the other, a person will have sickle cell trait . People with sickle cell trait are generally healthy. Only rarely do people with sickle cell trait have complications similar to those seen in people ...

  1. Fuel cell system with interconnect

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhien; Goettler, Richard

    2016-12-20

    The present invention includes an integrated planar, series connected fuel cell system having electrochemical cells electrically connected via interconnects, wherein the anodes of the electrochemical cells are protected against Ni loss and migration via an engineered porous anode barrier layer.

  2. Rejuvenation of automotive fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Yu Seung; Langlois, David A.

    2016-08-23

    A process for rejuvenating fuel cells has been demonstrated to improve the performance of polymer exchange membrane fuel cells with platinum/ionomer electrodes. The process involves dehydrating a fuel cell and exposing at least the cathode of the fuel cell to dry gas (nitrogen, for example) at a temperature higher than the operating temperature of the fuel cell. The process may be used to prolong the operating lifetime of an automotive fuel cell.

  3. Fibronectin-cell interactions

    DEFF Research Database (Denmark)

    Couchman, J R; Austria, M R; Woods, A

    1990-01-01

    Fibronectins are widespread extracellular matrix and body fluid glycoproteins, capable of multiple interactions with cell surfaces and other matrix components. Their structure at a molecular level has been resolved, yet there are still many unanswered questions regarding their biologic activity...... in vivo. Much data suggests that fibronectins may promote extracellular matrix assembly, and cell adhesion to those matrices. However, one outstanding enigma is that fibronectins may, under different circumstances, promote both cell migration and anchorage. An analysis of the interaction of fibroblasts...... with proteolytically derived and purified domains of plasma fibronectin revealed that the type of adhesion and the correlated cytoskeletal organization depended on multiple interactions of fibronectin domains with the cell surface. Human dermal fibroblasts were capable of interacting with the integrin-binding domain...

  4. Plant Stem Cells

    National Research Council Canada - National Science Library

    Greb, Thomas; Lohmann, Jan U

    2016-01-01

    .... While the promise of organ regeneration and the end of cancer have captured our imagination, it has gone almost unnoticed that plant stem cells represent the ultimate origin of much of the food we...

  5. Metaphyseal giant cell tumor

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, L.F.; Hemais, P.M.P.G.; Aymore, I.L.; Carmo, M.C.R. do; Cunha, M.E.P.R. da; Resende, C.M.C.

    Three cases of metaphyseal giant cell tumor are presented. A review of the literature is done, demostrating the lesion is rare and that there are few articles about it. Age incidence and characteristics of the tumor are discussed.

  6. RSW Cell Centered Grids

    Data.gov (United States)

    National Aeronautics and Space Administration — New cell centered grids are generated to complement the node-centered ones uploaded. Six tarballs containing the coarse, medium, and fine mixed-element and pure tet....

  7. Whole cell entrapment techniques.

    Science.gov (United States)

    Trelles, Jorge A; Rivero, Cintia W

    2013-01-01

    Microbial whole cells are efficient, ecological, and low-cost catalysts that have been successfully applied in the pharmaceutical, environmental, and alimentary industries, among others. Microorganism immobilization is a good way to carry out the bioprocess under preparative conditions. The main advantages of this methodology lie in their high operational stability, easy upstream separation and bioprocess scale-up feasibility. Cell entrapment is the most widely used technique for whole cell immobilization. This technique-in which the cells are included within a rigid network-is porous enough to allow the diffusion of substrates and products, protects the selected microorganism from the reaction medium, and has high immobilization efficiency (100 % in most cases).

  8. Acoustics Noise Test Cell

    Data.gov (United States)

    Federal Laboratory Consortium — The Acoustic Noise Test Cell at the NASA/Caltech Jet Propulsion Laboratory (JPL) is located adjacent to the large vibration system; both are located in a class 10K...

  9. Photovoltaic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Nielson, Gregory N; Cruz-Campa, Jose Luis; Okandan, Murat; Resnick, Paul J

    2014-05-20

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electricity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  10. CAM and NK Cells

    Directory of Open Access Journals (Sweden)

    Kazuyoshi Takeda

    2004-01-01

    Full Text Available It is believed that tumor development, outgrowth and metastasis are under the surveillance of the immune system. Although both innate and acquired immune systems play roles, innate immunity is the spearhead against tumors. Recent studies have revealed the critical role of natural killer (NK cells in immune surveillance and that NK cell activity is considerably influenced by various agents, such as environmental factors, stress, foods and drugs. Some of these NK cell stimulants have been used in complementary and alternative medicine (CAM since ancient times. Therefore, the value of CAM should be re-evaluated from this point of view. In this review, we overview the intimate correlation between NK cell functions and CAM agents, and discuss possible underlying mechanisms mediating this. In particular, neuro-immune crosstalk and receptors for CAM agents are the most important and interesting candidates for such mechanisms.

  11. Mast cells & Company

    Directory of Open Access Journals (Sweden)

    Friederike eJönsson

    2012-02-01

    Full Text Available Classically, allergy depends on IgE antibodies and on high-affinity IgE receptors expressed by mast cells and basophils. This long accepted IgE/FcεRI/mast cell paradigm, on which the definition of immediate hypersensitivity was based in the Gell and Coomb’s classification, appears too reductionist. Recently accumulated evidence indeed requires that not only IgE but also IgG antibodies, that not only FcεRI but also FcγR of the different types, that not only mast cells and basophils but also neutrophils, monocytes, macrophages, eosinophils, and other myeloid cells by considered as important players in allergy. This view markedly changes our understanding of allergic diseases and, possibly, their treatment.

  12. Beta Cell Breakthroughs

    Science.gov (United States)

    ... supply one person's insulin needs. Floating in a coffee cup–sized flask of reddish liquid in Melton's ... cells with nutrients and oxygen and transport their waste away. If the box is too big, only ...

  13. The Giant Cell.

    Science.gov (United States)

    Stockdale, Dennis

    1998-01-01

    Provides directions for the construction of giant plastic cells, including details for building and installing the organelles. Also contains instructions for preparing the ribosomes, nucleolus, nucleus, and mitochondria. (DDR)

  14. Red Cell Distribution Width

    Science.gov (United States)

    ... used to diagnose: Other blood disorders such as thalassemia , an inherited disease that can cause severe anemia ... cold hands and feet A family history of thalassemia, sickle cell anemia or other inherited blood disorder ...

  15. Cell Centred Database (CCDB)

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Cell Centered Database (CCDB) is a web accessible database for high resolution 2D, 3D and 4D data from light and electron microscopy, including correlated imaging.

  16. Thin Solid Oxide Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

  17. Colorful Microbial Cell Factories

    DEFF Research Database (Denmark)

    Petersen, Pia Damm

    Yeast cell factories are powerful tools used for the production of high-value natural compounds otherwise not easily available. Many bioactive and industrially important plant secondary metabolites can be produced in yeast by engineering their biosynthetic pathways into yeast cells, as these both...... anthocyanins. Yeast cell factories present a platform to circumvent the problem of low yields of interesting molecular structures in plant tissues, as hand-picking of desired enzyme activities allows for specific biosynthesis of the precise pigment of interest, as well as choosing more stable structures...... for heterologous biosynthesis is possible. In cell factories, great improvements in yields can be achieved through molecular engineering of flux from endogenous yeast precursors, e.g. by elimination of by-product formation, and by genetic optimization of pathway components, such as fine-tuning of expression levels...

  18. Plasma cell leukemia

    DEFF Research Database (Denmark)

    Fernández de Larrea, C; Kyle, R A; Durie, B G M

    2013-01-01

    Plasma cell leukemia (PCL) is a rare and aggressive variant of myeloma characterized by the presence of circulating plasma cells. It is classified as either primary PCL occurring at diagnosis or as secondary PCL in patients with relapsed/refractory myeloma. Primary PCL is a distinct clinic......-pathological entity with different cytogenetic and molecular findings. The clinical course is aggressive with short remissions and survival duration. The diagnosis is based upon the percentage (≥ 20%) and absolute number (≥ 2 × 10(9)/l) of plasma cells in the peripheral blood. It is proposed that the thresholds...... regimens and bortezomib-based regimens are recommended followed by high-dose therapy with autologous stem cell transplantation if feasible. Allogeneic transplantation can be considered in younger patients. Prospective multicenter studies are required to provide revised definitions and better understanding...

  19. The intestinal stem cell.

    NARCIS (Netherlands)

    Barker, N.; van de Wetering, M.L.; Clevers, H.

    2008-01-01

    The epithelium of the adult mammalian intestine is in a constant dialog with its underlying mesenchyme to direct progenitor proliferation, lineage commitment, terminal differentiation, and, ultimately, cell death. The epithelium is shaped into spatially distinct compartments that are dedicated to

  20. Acoustics Noise Test Cell

    Data.gov (United States)

    Federal Laboratory Consortium — The Acoustic Noise Test Cell at the NASA/Caltech Jet Propulsion Laboratory (JPL) is located adjacent to the large vibration system; both are located in a class 10K...

  1. Photovoltaic solar cell

    Energy Technology Data Exchange (ETDEWEB)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  2. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

    2013-11-26

    A photovoltaic solar cell for generating electricity from sunlight is disclosed. The photovoltaic solar cell comprises a plurality of spaced-apart point contact junctions formed in a semiconductor body to receive the sunlight and generate the electicity therefrom, the plurality of spaced-apart point contact junctions having a first plurality of regions having a first doping type and a second plurality of regions having a second doping type. In addition, the photovoltaic solar cell comprises a first electrical contact electrically connected to each of the first plurality of regions and a second electrical contact electrically connected to each of the second plurality of regions, as well as a passivation layer covering major surfaces and sidewalls of the photovoltaic solar cell.

  3. Targeting tumour Cell Plasticity

    Institute of Scientific and Technical Information of China (English)

    Elizabeth D. WILLIAMS

    2009-01-01

    @@ Her research is focused on understanding the mechanisms of tumour progression and metastasis, particularly in uro-logical carcinomas (bladder and prostate). Tumour cell plasticity, including epithelial-mesenchymal transition, is a cen-tral theme in Dr Williams' work.

  4. Thin Solid Oxide Cell

    DEFF Research Database (Denmark)

    2010-01-01

    The present invention relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material, at least one metal and a catalyst...... material, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same. The present invention also relates to a thin and in principle unsupported solid oxide cell, comprising at least a porous anode layer, an electrolyte layer and a porous...... cathode layer, wherein the anode layer and the cathode layer comprise an electrolyte material and a catalyst material, wherein the electrolyte material is doper zirconia, and wherein the overall thickness of the thin reversible cell is about 150 [mu]m or less, and to a method for producing same...

  5. Plasma Cell Cheilitis

    Directory of Open Access Journals (Sweden)

    Thami Gurvinder P

    1999-01-01

    Full Text Available A case of plasma cell cheilitis with good response to glucocorticoids, is described for its rarity and probable aetiological correlation with habit of use of nasal snuff is discussed.

  6. Merkel cell tumor.

    Science.gov (United States)

    Kitazawa, M; Watanabe, H; Kobayashi, H; Ohnishi, Y; Shitara, A; Nitto, H

    1987-06-01

    A Merkel cell tumor appeared on the left cheek of an 83-year-old female was reported. The tumor was located mainly in the dermis and infiltrated to the subcutaneous adipose tissue with an involvement of the blood vessels and lymphatics at the periphery. Electron-microscopically, few of the dense-cored granules and the single globular aggregates of intermediate filaments at the nuclear indentations were observed. Electron-microscopic uranaffin reaction proved positive reaction on the dense-cored granules. Half of the cytoplasmic border was smooth, while the rest had short projections. Desmosomes or junctional complexes were not detected among the tumor cells. Immunohistochemically, the cytoplasm of tumor cell showed positive reaction to both neuron-specific enolase (NSE) and keratin. The single globular positive spots of the latter were localized in accordance with the aggregates of intermediate filaments. These findings suggested a neurogenic origin with double differentiation, epithelial and neuroendocrine, of the Merkel cell tumor.

  7. Intestinal M cells.

    Science.gov (United States)

    Ohno, Hiroshi

    2016-02-01

    We have an enormous number of commensal bacteria in our intestine, moreover, the foods that we ingest and the water we drink is sometimes contaminated with pathogenic microorganisms. The intestinal epithelium is always exposed to such microbes, friend or foe, so to contain them our gut is equipped with specialized gut-associated lymphoid tissue (GALT), literally the largest peripheral lymphoid tissue in the body. GALT is the intestinal immune inductive site composed of lymphoid follicles such as Peyer's patches. M cells are a subset of intestinal epithelial cells (IECs) residing in the region of the epithelium covering GALT lymphoid follicles. Although the vast majority of IEC function to absorb nutrients from the intestine, M cells are highly specialized to take up intestinal microbial antigens and deliver them to GALT for efficient mucosal as well as systemic immune responses. I will discuss recent advances in our understanding of the molecular mechanisms of M-cell differentiation and functions.

  8. The cell biology of T-dependent B cell activation

    DEFF Research Database (Denmark)

    Owens, T; Zeine, R

    1989-01-01

    The requirement that CD4+ helper T cells recognize antigen in association with class II Major Histocompatibility Complex (MHC) encoded molecules constrains T cells to activation through intercellular interaction. The cell biology of the interactions between CD4+ T cells and antigen-presenting cells...... includes multipoint intermolecular interactions that probably involve aggregation of both polymorphic and monomorphic T cell surface molecules. Such aggregations have been shown in vitro to markedly enhance and, in some cases, induce T cell activation. The production of T-derived lymphokines that have been...... implicated in B cell activation is dependent on the T cell receptor for antigen and its associated CD3 signalling complex. T-dependent help for B cell activation is therefore similarly MHC-restricted and involves T-B intercellular interaction. Recent reports that describe antigen-independent B cell...

  9. Concise Review: Asymmetric Cell Divisions in Stem Cell Biology

    Directory of Open Access Journals (Sweden)

    Florian Murke

    2015-11-01

    Full Text Available Somatic stem cells are rare cells with unique properties residing in many organs and tissues. They are undifferentiated cells responsible for tissue regeneration and homeostasis, and contain both the capacity to self-renew in order to maintain their stem cell potential and to differentiate towards tissue-specific, specialized cells. However, the knowledge about the mechanisms controlling somatic stem cell fate decisions remains sparse. One mechanism which has been described to control daughter cell fates in selected somatic stem cell systems is the process of asymmetric cell division (ACD. ACD is a tightly regulated and evolutionary conserved process allowing a single stem or progenitor cell to produce two differently specified daughter cells. In this concise review, we will summarize and discuss current concepts about the process of ACD as well as different ACD modes. Finally, we will recapitulate the current knowledge and our recent findings about ACD in human hematopoiesis.

  10. Dazl Promotes Germ Cell Differentiation from Embryonic Stem Cells

    Institute of Scientific and Technical Information of China (English)

    Zhuo Yu; Ping Ji; Jinping Cao; Shu Zhu; Yao Li; Lin Zheng; Xuejin Chen; Lixin Feng

    2009-01-01

    It has been demonstrated that through the formation of embryoid bodies (Ebs) germ cells can be derived from embryonic stem (ES) cells. Here, we describe a transgene expression approach to derive germ cells directly from ES cells in vitro without EB formation. Through the ectopic expression of Deleted in Azoospermia-Like (Dazl), a germ cell-specific RNA-binding protein,both motile tailed-sperm and oocytes were induced from mouse ES (mES) cells in culture. Furthermore, transient overexpression of Dazl led to suppression of Nanog but induced germ cell nuclear antigen in mES cells. Dazl knockdown resulted in reduction in the expression of germ cell markers including Stella, MVH and Prdm1. Our study indicates that Dazl is a master gene controlling germ cell differentiation and that ectopic expression of Dazl promotes the dynamic differentiation of mouse ES cells into gametes in vitro.

  11. Optimized lithium oxyhalide cells

    Science.gov (United States)

    Kilroy, W. P.; Schlaikjer, C.; Polsonetti, P.; Jones, M.

    1993-04-01

    Lithium thionyl chloride cells were optimized with respect to electrolyte and carbon cathode composition. Wound 'C-size' cells with various mixtures of Chevron acetylene black with Ketjenblack EC-300J and containing various concentrations of LiAlCl4 and derivatives, LiGaCl4, and mixtures of SOCl2 and SO2Cl2 were evaluated as a function of discharge rate, temperature, and storage condition.

  12. Parietal cell vagotomy.

    Science.gov (United States)

    Cumberland, V H; Coupland, G A

    1975-07-12

    In a series of 100 consecutive patients who had parietal cell vagotomy performed, no drainage procedure was performed in 56 while 44 were drained. Dumping was significantly less in those who were not drained. All patients were tested for adequacy of vagotomy and for function of the nerve of Latarget at operation. Four patients have had further operations, two for proven recurrent ulcers. Parietal cell vagotomy has given excellent clinical results in this group of patients.

  13. Liquid fuel cells.

    Science.gov (United States)

    Soloveichik, Grigorii L

    2014-01-01

    The advantages of liquid fuel cells (LFCs) over conventional hydrogen-oxygen fuel cells include a higher theoretical energy density and efficiency, a more convenient handling of the streams, and enhanced safety. This review focuses on the use of different types of organic fuels as an anode material for LFCs. An overview of the current state of the art and recent trends in the development of LFC and the challenges of their practical implementation are presented.

  14. Regulatory T cell memory

    OpenAIRE

    Rosenblum, Md; Way, SS; Abbas, AK

    2015-01-01

    © 2015 Nature Publishing Group, a division of Macmillan Publishers Limited. All Rights Reserved. Memory for antigen is a defining feature of adaptive immunity. Antigen-specific lymphocyte populations show an increase in number and function after antigen encounter and more rapidly re-expand upon subsequent antigen exposure. Studies of immune memory have primarily focused on effector B cells and T cells with microbial specificity, using prime–challenge models of infection. However, recent work ...

  15. Single cell dynamic phenotyping

    OpenAIRE

    Katherin Patsch; Chi-Li Chiu; Mark Engeln; Agus, David B.; Parag Mallick; Shannon M. Mumenthaler; Daniel Ruderman

    2016-01-01

    Live cell imaging has improved our ability to measure phenotypic heterogeneity. However, bottlenecks in imaging and image processing often make it difficult to differentiate interesting biological behavior from technical artifact. Thus there is a need for new methods that improve data quality without sacrificing throughput. Here we present a 3-step workflow to improve dynamic phenotype measurements of heterogeneous cell populations. We provide guidelines for image acquisition, phenotype track...

  16. Dentinogenic ghost cell tumor

    Directory of Open Access Journals (Sweden)

    Singhaniya Shikha

    2009-01-01

    Full Text Available Dentinogenic ghost cell tumor (DGCT is a rare tumorous form of calcifying odontogenic cyst and only a small number of cases have been described. It is a locally invasive neoplasm that is characterized by ameloblastoma-like epithelial islands, ghost cells and dentinoid. The present report describes a case of a 21-year-old male with a tumor in the posterior region of the mandible, showing features of DGCT.

  17. Thin, Lightweight Solar Cell

    Science.gov (United States)

    Brandhorst, Henry W., Jr.; Weinberg, Irving

    1991-01-01

    Improved design for thin, lightweight solar photovoltaic cells with front contacts reduces degradation of electrical output under exposure to energetic charged particles (protons and electrons). Increases ability of cells to maintain structural integrity under exposure to ultraviolet radiation by eliminating ultraviolet-degradable adhesives used to retain cover glasses. Interdigitated front contacts and front junctions formed on semiconductor substrate. Mating contacts formed on back surface of cover glass. Cover glass and substrate electrostatically bonded together.

  18. Olfactory ensheathing cell tumor

    Directory of Open Access Journals (Sweden)

    Ippili Kaushal

    2009-01-01

    Full Text Available Olfactory ensheathing cells (OECs are found in the olfactory bulb and olfactory nasal mucosa. They resemble Schwann cells on light and electron microscopy, however, immunohistochemical staining can distinguish between the two. There are less than 30 cases of olfactory groove schwannomas reported in the literature while there is only one reported case of OEC tumor. We report an OEC tumor in a 42-year-old male and discuss the pathology and origin of this rare tumor.

  19. Syndecans and cell adhesion

    DEFF Research Database (Denmark)

    Couchman, J R; Chen, L; Woods, A

    2001-01-01

    Now that transmembrane signaling through primary cell-matrix receptors, integrins, is being elucidated, attention is turning to how integrin-ligand interactions can be modulated. Syndecans are transmembrane proteoglycans implicated as coreceptors in a variety of physiological processes, including...... cell adhesion, migration, response to growth factors, development, and tumorigenesis. This review will describe this family of proteoglycans in terms of their structures and functions and their signaling in conjunction with integrins, and indicate areas for future research....

  20. Nanodiamond internalization in cells and the cell uptake mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Perevedentseva, E. [National Dong Hwa University, Department of Physics (China); Hong, S.-F.; Huang, K.-J. [National Dong Hwa University, Department of Life Sciences (China); Chiang, I.-T.; Lee, C.-Y. [National Dong Hwa University, Department of Physics (China); Tseng, Y.-T. [National Dong Hwa University, Department of Life Sciences (China); Cheng, C.-L., E-mail: clcheng@mail.ndhu.edu.tw [National Dong Hwa University, Department of Physics (China)

    2013-08-15

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed.

  1. Nanodiamond internalization in cells and the cell uptake mechanism

    Science.gov (United States)

    Perevedentseva, E.; Hong, S.-F.; Huang, K.-J.; Chiang, I.-T.; Lee, C.-Y.; Tseng, Y.-T.; Cheng, C.-L.

    2013-08-01

    Cell type-dependent penetration of nanodiamond in living cells is one of the important factors for using nanodiamond as cellular markers/labels, for drug delivery as well as for other biomedical applications. In this work, internalization of 100 nm nanodiamonds by A549 lung human adenocarcinoma cell, Beas-2b non-tumorigenic human bronchial epithelial cell, and HFL-1 fibroblast-like human fetal lung cell is studied and compared. The penetration of nanodiamond into the cells was observed using confocal fluorescence imaging and Raman imaging methods. Visualization of the nanodiamond in cells allows comparison of the internalization for diamond nanoparticles in cancer A549 cell, non-cancer HFL-1, and Beas-2b cells. The dose-dependent and time-dependent behavior of nanodiamond uptake is observed in both cancer as well as non-cancer cells. The mechanism of nanodiamond uptake by cancer and non-cancer cells is analyzed by blocking different pathways. The uptake of nanodiamond in both cancer and non-cancer cells was found predominantly via clathrin-dependent endocytosis. In spite of observed similarity in the uptake mechanism for cancer and non-cancer cells, the nanodiamond uptake for cancer cell quantitatively exceeds the uptake for non-cancer cells, for the studied cell lines. The observed difference in internalization of nanodiamond by cancer and non-cancer cells is discussed.

  2. Stem cells - biological update and cell therapy progress.

    Science.gov (United States)

    Girlovanu, Mihai; Susman, Sergiu; Soritau, Olga; Rus-Ciuca, Dan; Melincovici, Carmen; Constantin, Anne-Marie; Mihu, Carmen Mihaela

    2015-01-01

    In recent years, the advances in stem cell research have suggested that the human body may have a higher plasticity than it was originally expected. Until now, four categories of stem cells were isolated and cultured in vivo: embryonic stem cells, fetal stem cells, adult stem cells and induced pluripotent stem cells (hiPSCs). Although multiple studies were published, several issues concerning the stem cells are still debated, such as: the molecular mechanisms of differentiation, the methods to prevent teratoma formation or the ethical and religious issues regarding especially the embryonic stem cell research. The direct differentiation of stem cells into specialized cells: cardiac myocytes, neural cells, pancreatic islets cells, may represent an option in treating incurable diseases such as: neurodegenerative diseases, type I diabetes, hematologic or cardiac diseases. Nevertheless, stem cell-based therapies, based on stem cell transplantation, remain mainly at the experimental stages and their major limitation is the development of teratoma and cancer after transplantation. The induced pluripotent stem cells (hiPSCs) represent a prime candidate for future cell therapy research because of their significant self-renewal and differentiation potential and the lack of ethical issues. This article presents an overview of the biological advances in the study of stem cells and the current progress made in the field of regenerative medicine.

  3. Endothelial cells derived from human embryonic stem cells

    Science.gov (United States)

    Levenberg, Shulamit; Golub, Justin S.; Amit, Michal; Itskovitz-Eldor, Joseph; Langer, Robert

    2002-04-01

    Human embryonic stem cells have the potential to differentiate into various cell types and, thus, may be useful as a source of cells for transplantation or tissue engineering. We describe here the differentiation steps of human embryonic stem cells into endothelial cells forming vascular-like structures. The human embryonic-derived endothelial cells were isolated by using platelet endothelial cell-adhesion molecule-1 (PECAM1) antibodies, their behavior was characterized in vitro and in vivo, and their potential in tissue engineering was examined. We show that the isolated embryonic PECAM1+ cells, grown in culture, display characteristics similar to vessel endothelium. The cells express endothelial cell markers in a pattern similar to human umbilical vein endothelial cells, their junctions are correctly organized, and they have high metabolism of acetylated low-density lipoprotein. In addition, the cells are able to differentiate and form tube-like structures when cultured on matrigel. In vivo, when transplanted into SCID mice, the cells appeared to form microvessels containing mouse blood cells. With further studies, these cells could provide a source of human endothelial cells that could be beneficial for potential applications such as engineering new blood vessels, endothelial cell transplantation into the heart for myocardial regeneration, and induction of angiogenesis for treatment of regional ischemia.

  4. Substrate Stiffness and Cell Area Predict Cellular Traction Stresses in Single Cells and Cells in Contact

    OpenAIRE

    Califano, Joseph P.; Reinhart-King, Cynthia A.

    2010-01-01

    Cells generate traction stresses against their substrate during adhesion and migration, and traction stresses are used in part by the cell to sense the substrate. While it is clear that traction stresses, substrate stiffness, and cell area are related, it is unclear whether or how area and substrate stiffness affect force generation in cells. Moreover, multiple studies have investigated traction stresses of single cells, but few have focused on forces exerted by cells in contact, which more c...

  5. On the cell biology of pit cells, the liver-specific NK cells

    Institute of Scientific and Technical Information of China (English)

    Dian Zhong Luo; David Vermijlen; Bülent Ahishali; Vasilis Triantis; Georgia Plakoutsi; Filip Braet; Karin Vanderkerken; Eddie Wisse

    2000-01-01

    @@ INTRODUCTION Natural killer (NK) cells are functionally defined by their ability to kill certain tumor cells and virusinfected cells without prior sensitization[1]. NK cells comprise about 10% to 15% of lymphocytes in the peripheral blood and most of these cells in human and rat have the morphology of large granular lymphocytes ( LGL )[2]. However, recent studies have demonstrated that small agranular lymphocytes, lacking CD3 expression, have cytolytic activity comparable to NK cells[3].

  6. Anti-regulatory T cells

    DEFF Research Database (Denmark)

    Andersen, Mads Hald

    2017-01-01

    Our initial understanding of immune-regulatory cells was based on the discovery of suppressor cells that assure peripheral T-cell tolerance and promote immune homeostasis. Research has particularly focused on the importance of regulatory T cells (Tregs) for immune modulation, e.g. directing host...... responses to tumours or inhibiting autoimmunity development. However, recent studies report the discovery of self-reactive pro-inflammatory T cells—termed anti-regulatory T cells (anti-Tregs)—that target immune-suppressive cells. Thus, regulatory cells can now be defined as both cells that suppress immune...... reactions as well as effector cells that counteract the effects of suppressor cells and support immune reactions. Self-reactive anti-Tregs have been described that specifically recognize human leukocyte antigen-restricted epitopes derived from proteins that are normally expressed by regulatory immune cells...

  7. [Progress in dedifferentiated fat cells].

    Science.gov (United States)

    Cheng, Feifei; Yang, Zhi; Qian, Cheng

    2014-10-01

    When mature adipocytes are subjected to an in vitro dedifferentiation strategy referred to as ceiling culture, these mature adipocytes can revert to dedifferentiated fat (DFAT) cells. DFAT cells have many advantages compared with adipose-derived stem cells (ASCs) and bone marrow mesenchymal stem cells (BMSCs). For example, DFAT cells are homogeneous and could be obtained from donors regardless of their age. Furthermore, DFAT cells also have the same multi-lineage potentials and low immunogenicity as ASCs. As an excellent source of seed cells for tissue engineering and stem cell transplantation, DFAT cells have better prospects in the treatment of many clinical diseases, such as bone defects, neurological diseases, ischemic heart disease and kidney disease. It is necessary to make more intensive studies of DFAT cells. This article summarizes progresses in the immunological characteristics, differentiation ability and potential clinical applications of DFAT cells.

  8. Cell Cycle Progression of Human Cells Cultured in Rotating Bioreactor

    Science.gov (United States)

    Parks, Kelsey

    2009-01-01

    Space flight has been shown to alter the astronauts immune systems. Because immune performance is complex and reflects the influence of multiple organ systems within the host, scientists sought to understand the potential impact of microgravity alone on the cellular mechanisms critical to immunity. Lymphocytes and their differentiated immature form, lymphoblasts, play an important and integral role in the body's defense system. T cells, one of the three major types of lymphocytes, play a central role in cell-mediated immunity. They can be distinguished from other lymphocyte types, such as B cells and natural killer cells by the presence of a special receptor on their cell surface called T cell receptors. Reported studies have shown that spaceflight can affect the expression of cell surface markers. Cell surface markers play an important role in the ability of cells to interact and to pass signals between different cells of the same phenotype and cells of different phenotypes. Recent evidence suggests that cell-cycle regulators are essential for T-cell function. To trigger an effective immune response, lymphocytes must proliferate. The objective of this project is to investigate the changes in growth of human cells cultured in rotating bioreactors and to measure the growth rate and the cell cycle distribution for different human cell types. Human lymphocytes and lymphoblasts will be cultured in a bioreactor to simulate aspects of microgravity. The bioreactor is a cylindrical culture vessel that incorporates the aspects of clinostatic rotation of a solid fluid body around a horizontal axis at a constant speed, and compensates gravity by rotation and places cells within the fluid body into a sustained free-fall. Cell cycle progression and cell proliferation of the lymphocytes will be measured for a number of days. In addition, RNA from the cells will be isolated for expression of genes related in cell cycle regulations.

  9. Microfluidic Cell Cycle Analysis of Spread Cells by DAPI Staining

    Directory of Open Access Journals (Sweden)

    Jing Sun

    2017-01-01

    Full Text Available Single-cell cell cycle analysis is an emerging technique that requires detailed exploration of the image analysis process. In this study, we established a microfluidic single-cell cell cycle analysis method that can analyze cells in small numbers and in situ on a microfluidic chip. In addition, factors that influenced the analysis were carefully investigated. U87 or HeLa cells were seeded and attached to microfluidic channels before measurement. Cell nucleic DNA was imaged by 4′-6-diamidino-2-phenylindole (DAPI staining under a fluorescent microscope and subsequently fluorescent intensities of the cell nuclei DNA were converted to depict histograms for cell cycle phases. DAPI concentration, microscopic magnification, exposure time and cell number were examined for optimal cell cycle analysis conditions. The results showed that as few as a few hundred cells could be measured by DAPI staining in the range of 0.4–0.6 μg/mL to depict histograms with typical cell cycle phase distribution. Microscopic magnification during image acquisition, however, could distort the phase distribution. Exposure time did not significantly affect the cell cycle analysis. Furthermore, cell cycle inhibitor rapamycin treatment changed the cell cycle phase distribution as expected. In conclusion, a method for microfluidic single-cell cell cycle analysis of spread cells in situ was developed. Factors such as dye concentration and microscopic magnification had more influence on cell cycle phase distribution. Further studies will focus on detail differentiation of cell cycle phases and the application of such a method for biological meanings.

  10. Cell Cycle Progression of Human Cells Cultured in Rotating Bioreactor

    Science.gov (United States)

    Parks, Kelsey

    2009-01-01

    Space flight has been shown to alter the astronauts immune systems. Because immune performance is complex and reflects the influence of multiple organ systems within the host, scientists sought to understand the potential impact of microgravity alone on the cellular mechanisms critical to immunity. Lymphocytes and their differentiated immature form, lymphoblasts, play an important and integral role in the body's defense system. T cells, one of the three major types of lymphocytes, play a central role in cell-mediated immunity. They can be distinguished from other lymphocyte types, such as B cells and natural killer cells by the presence of a special receptor on their cell surface called T cell receptors. Reported studies have shown that spaceflight can affect the expression of cell surface markers. Cell surface markers play an important role in the ability of cells to interact and to pass signals between different cells of the same phenotype and cells of different phenotypes. Recent evidence suggests that cell-cycle regulators are essential for T-cell function. To trigger an effective immune response, lymphocytes must proliferate. The objective of this project is to investigate the changes in growth of human cells cultured in rotating bioreactors and to measure the growth rate and the cell cycle distribution for different human cell types. Human lymphocytes and lymphoblasts will be cultured in a bioreactor to simulate aspects of microgravity. The bioreactor is a cylindrical culture vessel that incorporates the aspects of clinostatic rotation of a solid fluid body around a horizontal axis at a constant speed, and compensates gravity by rotation and places cells within the fluid body into a sustained free-fall. Cell cycle progression and cell proliferation of the lymphocytes will be measured for a number of days. In addition, RNA from the cells will be isolated for expression of genes related in cell cycle regulations.

  11. Cell supermarket: Adipose tissue as a source of stem cells

    Science.gov (United States)

    Adipose tissue is derived from numerous sources, and in recent years has been shown to provide numerous cells from what seemingly was a population of homogeneous adipocytes. Considering the types of cells that adipose tissue-derived cells may form, these cells may be useful in a variety of clinical ...

  12. 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.

  13. CellTracks cytometer for detection of circulating tumor cells

    NARCIS (Netherlands)

    Tibbe, A.G.J.; Kooi, van der A.; Groot, de M.R.; Vermes, I.

    2003-01-01

    Introduction: In patients with carcinomas, tumor cells are shed into the circulation. The number of the circulating tumor cells is low and technology is needed that has sufficient sensitivity and specificity to enumerate and characterize these cells. The CellTracks system was developed to provide an

  14. Bidirectional regulation between B cells and T cells

    NARCIS (Netherlands)

    Margry, B.

    2014-01-01

    B cells were often thought of as simple precursors of end-stage effector cells that are merely in charge of antibody production. Research in the last decades has shown that B cells possess important other roles as well, including their involvement in the regulation and functioning of T cell-mediated

  15. 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.

  16. Selecting B cells and plasma cells to memory

    OpenAIRE

    2005-01-01

    Humoral immunity appears to be based on immunological memory provided by memory plasma cells, which secrete protective antibodies, and memory B cells, which react to antigen challenge by differentiating into plasma cells. How these differentiation pathways relate to each other, how cells are selected into these memory populations, and how these populations are maintained remains enigmatic.

  17. Sponge cell culture? A molecular identification method for sponge cells

    NARCIS (Netherlands)

    Sipkema, D.; Heilig, G.H.J.; Akkermans, A.D.L.; Osinga, R.; Tramper, J.; Wijffels, R.H.

    2003-01-01

    Dissociated sponge cells are easily confused with unicellular organisms. This has been an obstacle in the development of sponge-cell lines. We developed a molecular detection method to identify cells of the sponge Dysidea avara in dissociated cell cultures. The 18S ribosomal RNA gene from a Dysidea

  18. 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.

  19. Fuel Cell Electrodes for Hydrogen-Air Fuel Cell Assemblies.

    Science.gov (United States)

    The report describes the design and evaluation of a hydrogen-air fuel cell module for use in a portable hydrid fuel cell -battery system. The fuel ... cell module consists of a stack of 20 single assemblies. Each assembly contains 2 electrically independent cells with a common electrolyte compartment

  20. Hematopoietic cell differentiation from embryonic and induced pluripotent stem cells

    Science.gov (United States)

    2013-01-01

    Pluripotent stem cells, both embryonic stem cells and induced pluripotent stem cells, are undifferentiated cells that can self-renew and potentially differentiate into all hematopoietic lineages, such as hematopoietic stem cells (HSCs), hematopoietic progenitor cells and mature hematopoietic cells in the presence of a suitable culture system. Establishment of pluripotent stem cells provides a comprehensive model to study early hematopoietic development and has emerged as a powerful research tool to explore regenerative medicine. Nowadays, HSC transplantation and hematopoietic cell transfusion have successfully cured some patients, especially in malignant hematological diseases. Owing to a shortage of donors and a limited number of the cells, hematopoietic cell induction from pluripotent stem cells has been regarded as an alternative source of HSCs and mature hematopoietic cells for intended therapeutic purposes. Pluripotent stem cells are therefore extensively utilized to facilitate better understanding in hematopoietic development by recapitulating embryonic development in vivo, in which efficient strategies can be easily designed and deployed for the generation of hematopoietic lineages in vitro. We hereby review the current progress of hematopoietic cell induction from embryonic stem/induced pluripotent stem cells. PMID:23796405

  1. Optimizing cell viability in droplet-based cell deposition

    NARCIS (Netherlands)

    Hendriks, J.; Visser, C.W.; Henke, S.J.; Leijten, Jeroen Christianus Hermanus; Saris, Daniël B.F.; Sun, Chao; Lohse, Detlef; Karperien, Hermanus Bernardus Johannes

    2015-01-01

    Biofabrication commonly involves the use of liquid droplets to transport cells to the printed structure. However, the viability of the cells after impact is poorly controlled and understood, hampering applications including cell spraying, inkjet bioprinting, and laser-assisted cell transfer. Here,

  2. Schwann cells induce cancer cell dispersion and invasion

    Science.gov (United States)

    Deborde, Sylvie; Lyubchik, Anna; Zhou, Yi; He, Shizhi; McNamara, William F.; Chernichenko, Natalya; Lee, Sei-Young; Barajas, Fernando; Chen, Chun-Hao; Bakst, Richard L.; Vakiani, Efsevia; He, Shuangba; Hall, Alan; Wong, Richard J.

    2016-01-01

    Nerves enable cancer progression, as cancers have been shown to extend along nerves through the process of perineural invasion, which carries a poor prognosis. Furthermore, the innervation of some cancers promotes growth and metastases. It remains unclear, however, how nerves mechanistically contribute to cancer progression. Here, we demonstrated that Schwann cells promote cancer invasion through direct cancer cell contact. Histological evaluation of murine and human cancer specimens with perineural invasion uncovered a subpopulation of Schwann cells that associates with cancer cells. Coculture of cancer cells with dorsal root ganglion extracts revealed that Schwann cells direct cancer cells to migrate toward nerves and promote invasion in a contact-dependent manner. Upon contact, Schwann cells induced the formation of cancer cell protrusions in their direction and intercalated between the cancer cells, leading to cancer cell dispersion. The formation of these processes was dependent on Schwann cell expression of neural cell adhesion molecule 1 (NCAM1) and ultimately promoted perineural invasion. Moreover, NCAM1-deficient mice showed decreased neural invasion and less paralysis. Such Schwann cell behavior reflects normal Schwann cell programs that are typically activated in nerve repair but are instead exploited by cancer cells to promote perineural invasion and cancer progression. PMID:26999607

  3. Determinants of leader cells in collective cell migration.

    NARCIS (Netherlands)

    Khalil, A.; Friedl, P.H.A.

    2010-01-01

    Collective migration is a basic mechanism of cell translocation during morphogenesis, wound repair and cancer invasion. Collective movement requires cells to retain cell-cell contacts, exhibit group polarization with defined front-rear asymmetry, and consequently move as one multicellular unit. Depe

  4. Optimizing cell viability in droplet-based cell deposition

    NARCIS (Netherlands)

    Hendriks, Jan; Willem Visser, Claas; Henke, Sieger; Leijten, Jeroen; Saris, Daniël B F; Sun, Chao; Lohse, Detlef; Karperien, Marcel

    2015-01-01

    Biofabrication commonly involves the use of liquid droplets to transport cells to the printed structure. However, the viability of the cells after impact is poorly controlled and understood, hampering applications including cell spraying, inkjet bioprinting, and laser-assisted cell transfer. Here, w

  5. A fine romance: T follicular helper cells and B cells.

    Science.gov (United States)

    King, Cecile

    2011-06-24

    T follicular helper (Tfh) cells help B cells to generate affinity-matured antibodies. Three papers in this issue of Immunity (Choi et al., 2011; Kerfoot et al., 2011; Kitano et al., 2011) provide information about the reciprocal relationship between B cells and Tfh cells. Copyright © 2011 Elsevier Inc. All rights reserved.

  6. [On plant stem cells and animal stem cells].

    Science.gov (United States)

    You, Yun; Jiang, Chao; Huang, Lu-Qi

    2014-01-01

    A comparison of plant and animal stem cells can highlight core aspects of stem-cell biology. In both kingdoms, stem cells are defined by their clonogenic properties and are maintained by intercellular signals. The signaling molecules are different in plants and animals stem cell niches, but the roles of argonaute and polycomb group proteins suggest that there are some molecular similarities.

  7. The cerebral perivascular cells.

    Science.gov (United States)

    Angelov, D N; Walther, M; Streppel, M; Guntinas-Lichius, O; Neiss, W F

    1998-01-01

    This monograph reviews the literature and presents experimental data on the intracerebral presentation of antigen(s) to the immune system as a consequence of neuronal cell death. "Which cells are the antigen presenting cells (APC) of the brain?" is the main question of this book. The immune surveillance of the CNS occurs through specialized resident cells, which present (auto)antigen(s) to the immune system and thus initiate an (auto)immune response. There are four established prerequisites necessary to identify resident APC of the brain. First, the APC must be capable to phagocytose dead neurons. Second, in order to be recognized by T lymphocytes, these neuronophages must express Major Histocompatibility Complex (MHC) cells II glycoproteins on their surface. Third, in order to present (auto)antigen, the MHC class II-positive neuronophages must also be able to contact T lymphocytes. Fourth, in order to exert a stimulatory effect on T lymphocytes, the APC should be able to produce the cytokine interleukin-1 beta (IL-128 Mb). Three main tools were used to identify and characterize the APC of the brain. First, a lesion model was employed that yields a slowly progressing neuronal cell loss without disruption of the blood-brain barrier. This model consisted of resection of 10 mm of the facial nerve, which caused a slowly occurring neuronal death so that one year after resection the amount of facial neurons was about 44% of the control value. Second, neuronophages were labeled in vivo in situ via phagocytosis of the permanent fluorescent marker Fluoro-Gold (FG) from decaying pre-loaded facial motoneurons. Third, the FG-labeled neuronophages were immunocytochemically characterized with the new method "immunoquenching of fluorescence". Sections of the brainstem containing FG-labeled, i.e. fluorescent, neuronophages were incubated with a variety of primary antibodies, followed by avidin-HRP and DAB-nickel as a dark brown reaction product for bright-field microscopy. In the

  8. Bone marrow cells differentiation into organ cells using stem cell therapy.

    Science.gov (United States)

    Yang, Y-J; Li, X-L; Xue, Y; Zhang, C-X; Wang, Y; Hu, X; Dai, Q

    2016-07-01

    Bone marrow cells (BMC) are progenitors of bone, cartilage, skeletal tissue, the hematopoiesis-supporting stroma and adipocyte cells. BMCs have the potential to differentiate into neural cells, cardiac myocytes, liver hepatocytes, chondrocytes, renal, corneal, blood, and myogenic cells. The bone marrow cell cultures from stromal and mesenchymal cells are called multipotent adult progenitor cells (MAPCs). MAPCs can differentiate into mesenchymal cells, visceral mesoderm, neuroectoderm and endoderm in vitro. It has been shown that the stem cells derived from bone marrow cells (BMCs) can regenerate cardiac myocytes after myocardial infarction (MI). Adult bone marrow mesenchymal stem cells have the ability to regenerate neural cells. Neural stem/progenitor cells (NS/PC) are ideal for treating central nervous system (CNS) diseases, such as Alzheimer's, Parkinson's and Huntington disease. However, there are important ethical issues about the therapeutic use of stem cells. Neurons, cardiac myocytes, hepatocytes, renal cells, blood cells, chondrocytes and adipocytes regeneration from BMCs are very important in disease control. It is known that limbal epithelial stem cells in the cornea can repair the eye sight and remove symptoms of blindness. Stem cell therapy (SCT) is progressing well in animal models, but the use of SCT in human remains to be explored further.

  9. Knowledge discovery of cell-cell and cell-surface interactions

    Science.gov (United States)

    Su, Jing

    High-throughput cell culture is an emerging technology that shows promise as a tool for research in tissue engineering, drug discovery, and medical diagnostics. An important, but overlooked, challenge is the integration of experimental methods with information processing suitable for handling large databases of cell-cell and cell-substrate interactions. In this work the traditional global descriptions of cell behaviors and surface characteristics was shown insufficient for investigating short-distance cell-to-cell and cell-to-surface interactions. Traditional summary metrics cannot distinguish information of cell near neighborhood from the average, global features, thus often is not suitable for studying distance-sensitive cell behaviors. The problem of traditional summary metrics was addressed by introducing individual-cell based local metrics that emphasize cell local environment. An individual-cell based local data analysis method was established. Contact inhibition of cell proliferation was used as a benchmark for the effectiveness of the local metrics and the method. Where global, summary metrics were unsuccessful, the local metrics successfully and quantitatively distinguished the contact inhibition effects of MC3T3-E1 cells on PLGA, PCL, and TCPS surfaces. In order to test the new metrics and analysis method in detail, a model of cell contact inhibition was proposed. Monte Carlo simulation was performed for validating the individual-cell based local data analysis method as well as the cell model itself. The simulation results well matched with the experimental observations. The parameters used in the cell model provided new descriptions of both cell behaviors and surface characteristics. Based on the viewpoint of individual cells, the local metrics and local data analysis method were extended to the investigation of cell-surface interactions, and a new high-throughput screening and knowledge discovery method on combinatorial libraries, local cell

  10. Microfluidic Cell Cycle Analysis of Spread Cells by DAPI Staining

    OpenAIRE

    Jing Sun; Jiayu Zhang; Haibo Yang; Gongzhuo Wang; Yanzhao Li; Xuxin Zhang; Qidan Chen; Ming-Fei Lang

    2017-01-01

    Single-cell cell cycle analysis is an emerging technique that requires detailed exploration of the image analysis process. In this study, we established a microfluidic single-cell cell cycle analysis method that can analyze cells in small numbers and in situ on a microfluidic chip. In addition, factors that influenced the analysis were carefully investigated. U87 or HeLa cells were seeded and attached to microfluidic channels before measurement. Cell nucleic DNA was imaged by 4′-6-diamidino-2...

  11. Border cells versus border-like cells: are they alike?

    Science.gov (United States)

    Driouich, Azeddine; Durand, Caroline; Cannesan, Marc-Antoine; Percoco, Giuseppe; Vicré-Gibouin, Maité

    2010-09-01

    Roots of many plants are known to produce large numbers of 'border' cells that play a central role in root protection and the interaction of the root with the rhizosphere. Unlike border cells, border-like cells were described only recently in the model plant Arabidopsis thaliana and other Brassicaceae species and very little is known about the functional properties of border-like cells as compared with 'classical' border cells. To stimulate discussion and future research on this topic, the function of border cells and the way border-like cells are organized, maintained, and possibly involved in plant protection is discussed here.

  12. Exporting calcium from cells.

    Science.gov (United States)

    Guerini, Danilo; Coletto, Luisa; Carafoli, Ernesto

    2005-01-01

    All eukaryotic cells import Ca2+ through a number of variously gated plasma membrane channels. Once inside cells, Ca2+ transmits information to a large number of (enzyme) targets. Eventually, it must be exported again, to prevent the overloading of the cytosol with Ca2+. Two systems export Ca2+ from cells: a high affinity, low capacity Ca2+-ATPase, and a lower affinity, but much larger capacity, Na+/Ca2+ exchanger. The ATPase (commonly called the Ca2+ pump) is the fine-tuner of cell Ca2+, as it functions well even if the concentration of the ion drops below the microM level. It is a large enzyme, with 10 transmembrane domains and a C-terminal cytosolic tail that contains regulatory sites, including a calmodulin-binding domain. Four distinct gene products plus a large number of splice variants have been described. Some are tissue specific, the isoform 2 being specifically expressed in the sensorial cells of the Corti organ in the inner-ear. Its genetic absence causes deafness in mice. Two different families of the Na+/Ca2+ exchanger exist, one of which, originally described in photoreceptors, transports K+ and Ca2+ in exchange for Na+. The exchanger is particularly active in excitable cells, e.g., heart, where the necessity cyclically arises to rapidly eject large amounts of Ca2+. In addition to heart, the exchanger is particularly important to neurons: the cleavage of the most important neuronal isoform (NCX3) by calpains activated by excitotoxic treatments generates Ca2+ overload and eventually cell death.

  13. Single Cell Oncogenesis

    Science.gov (United States)

    Lu, Xin

    It is believed that cancer originates from a single cell that has gone through generations of evolution of genetic and epigenetic changes that associate with the hallmarks of cancer. In some cancers such as various types of leukemia, cancer is clonal. Yet in other cancers like glioblastoma (GBM), there is tremendous tumor heterogeneity that is likely to be caused by simultaneous evolution of multiple subclones within the same tissue. It is obvious that understanding how a single cell develops into a clonal tumor upon genetic alterations, at molecular and cellular levels, holds the key to the real appreciation of tumor etiology and ultimate solution for therapeutics. Surprisingly very little is known about the process of spontaneous tumorigenesis from single cells in human or vertebrate animal models. The main reason is the lack of technology to track the natural process of single cell changes from a homeostatic state to a progressively cancerous state. Recently, we developed a patented compound, photoactivatable (''caged'') tamoxifen analogue 4-OHC and associated technique called optochemogenetic switch (OCG switch), which we believe opens the opportunity to address this urgent biological as well as clinical question about cancer. We propose to combine OCG switch with genetically engineered mouse models of head and neck squamous cell carcinoma and high grade astrocytoma (including GBM) to study how single cells, when transformed through acute loss of tumor suppressor genes PTEN and TP53 and gain of oncogenic KRAS, can develop into tumor colonies with cellular and molecular heterogeneity in these tissues. The abstract is for my invited talk in session ``Beyond Darwin: Evolution in Single Cells'' 3/18/2016 11:15 AM.

  14. Cadium-induced bone loss: Effects in ovariectomized mice and osteoclast-like cells in culture

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, M.H.; Seed, T.M.; Peterson, D.P.; Moretti, E.S.; Kuhn, C.; Brice, L.F.; Choi, T.T.

    1988-01-01

    The research reported here was conducted to investigate the possibility that cadmium might be a factor that increases bone loss after the menopause. In our first study, we exposed female CF1 mice to a purified diet containing CdCl2 at either 0.25, 5.0, or 50 ppM Cd starting at 70 days of age. After 12 months of exposure, mice were ovariectomized (OV) or sham-operated (SO). After surgery, they remained on their respective diets for an additional six months before sacrifice. Results showed that neither ovariectomy alone nor dietary Cd exposure alone significantly decrease bone calcium content. However, dietary Cd at 50 ppM in combination with ovariectomy caused a striking decrease in the calcium content of mouse bones. The mice in the above study were quite old (435 days old at ovariectomy; 617 days old at sacrifice) and had been exposed to dietary cadmium for one year prior to removal of the ovaries. Consequently, the follow-up study reported here was conducted in mice whose skeletons were pre-labelled with UVCa. This study was designed to determine whether cadmium exposure would cause as increased release of UVCa from the skeletons of OV mice immediately after the start of cadmium exposure and in the absence of the one-year pre-exposure period present in our first study. Such results would indicate that cadmium might act directly on bone rather than indirectly by way of damage to another organ such as the kidney. 14 refs., 1 fig.

  15. Rho family proteins in cell adhesion and cell migration.

    Science.gov (United States)

    Evers, E E; Zondag, G C; Malliri, A; Price, L S; ten Klooster, J P; van der Kammen, R A; Collard, J G

    2000-06-01

    Cell migration and the regulation of cadherin-mediated homotypic cell-cell interactions are critical events during development, morphogenesis and wound healing. Aberrations in signalling pathways involved in the regulation of cell migration and cadherin-mediated cell-cell adhesion contribute to tumour invasion and metastasis. The rho family proteins, including cdc42, rac1 and rhoA, regulate signalling pathways that mediate the distinct actin cytoskeleton changes required for both cellular motility and cell-cell adhesion. Recent studies indicate that rac directly influences rho activity at the GTPase level and that the reciprocal balance between rac and rho activity can determine epithelial or mesenchymal cell morphology and migratory behaviour of epithelial (tumour) cells.

  16. Cryptococcal cell morphology affects host cell interactions and pathogenicity.

    Directory of Open Access Journals (Sweden)

    Laura H Okagaki

    Full Text Available Cryptococcus neoformans is a common life-threatening human fungal pathogen. The size of cryptococcal cells is typically 5 to 10 microm. Cell enlargement was observed in vivo, producing cells up to 100 microm. These morphological changes in cell size affected pathogenicity via reducing phagocytosis by host mononuclear cells, increasing resistance to oxidative and nitrosative stress, and correlated with reduced penetration of the central nervous system. Cell enlargement was stimulated by coinfection with strains of opposite mating type, and ste3aDelta pheromone receptor mutant strains had reduced cell enlargement. Finally, analysis of DNA content in this novel cell type revealed that these enlarged cells were polyploid, uninucleate, and produced daughter cells in vivo. These results describe a novel mechanism by which C. neoformans evades host phagocytosis to allow survival of a subset of the population at early stages of infection. Thus, morphological changes play unique and specialized roles during infection.

  17. Asymmetric cell division during T cell development controls downstream fate

    Science.gov (United States)

    Pham, Kim; Shimoni, Raz; Charnley, Mirren; Ludford-Menting, Mandy J.; Hawkins, Edwin D.; Ramsbottom, Kelly; Oliaro, Jane; Izon, David; Ting, Stephen B.; Reynolds, Joseph; Lythe, Grant; Molina-Paris, Carmen; Melichar, Heather; Robey, Ellen; Humbert, Patrick O.; Gu, Min

    2015-01-01

    During mammalian T cell development, the requirement for expansion of many individual T cell clones, rather than merely expansion of the entire T cell population, suggests a possible role for asymmetric cell division (ACD). We show that ACD of developing T cells controls cell fate through differential inheritance of cell fate determinants Numb and α-Adaptin. ACD occurs specifically during the β-selection stage of T cell development, and subsequent divisions are predominantly symmetric. ACD is controlled by interaction with stromal cells and chemokine receptor signaling and uses a conserved network of polarity regulators. The disruption of polarity by deletion of the polarity regulator, Scribble, or the altered inheritance of fate determinants impacts subsequent fate decisions to influence the numbers of DN4 cells arising after the β-selection checkpoint. These findings indicate that ACD enables the thymic microenvironment to orchestrate fate decisions related to differentiation and self-renewal. PMID:26370500

  18. Cell mechanics: integrating cell responses to mechanical stimuli.

    Science.gov (United States)

    Janmey, Paul A; McCulloch, Christopher A

    2007-01-01

    Forces are increasingly recognized as major regulators of cell structure and function, and the mechanical properties of cells are essential to the mechanisms by which cells sense forces, transmit them to the cell interior or to other cells, and transduce them into chemical signals that impact a spectrum of cellular responses. Comparison of the mechanical properties of intact cells with those of the purified cytoskeletal biopolymers that are thought to dominate their elasticity reveal the extent to which the studies of purified systems can account for the mechanical properties of the much more heterogeneous and complex cell. This review summarizes selected aspects of current work on cell mechanics with an emphasis on the structures that are activated in cell-cell contacts, that regulate ion flow across the plasma membrane, and that may sense fluid flow that produces low levels of shear stress.

  19. Dedifferentiated adipocyte-derived progeny cells (DFAT cells)

    Science.gov (United States)

    Wei, Shengjuan; Zan, Linsen; Hausman, Gary J; Rasmussen, Theodore P; Bergen, Werner G; Dodson, Michael V

    2013-01-01

    Analyses of mature adipocytes have shown that they possess a reprogramming ability in vitro, which is associated with dedifferentiation. The subsequent dedifferentiated fat cells (DFAT cells) are multipotent and can differentiate into adipocytes and other cell types as well. Mature adipocytes can be easily obtained by biopsy, and the cloned progeny cells are homogeneous in vitro. Therefore, DFAT cells (a new type of stem cell) may provide an excellent source of cells for tissue regeneration, engineering and disease treatment. The dedifferentiation of mature adipocytes, the multipotent capacity of DFAT cells and comparisons and contrasts with mesenchymal stem cells (MSCs) and induced pluripotent stem cells (iPS) are discussed in this review. PMID:23991357

  20. Cell cycle and cell signal transduction in marine phytoplankton

    Institute of Scientific and Technical Information of China (English)

    LIU Jingwen; JIAO Nianzhi; CAI Huinong

    2006-01-01

    As unicellular phytoplankton, the growth of a marine phytoplankton population results directly from the completion of a cell cycle, therefore, cell-environment communication is an important way which involves signal transduction pathways to regulate cell cycle progression and contribute to growth, metabolism and primary production and respond to their surrounding environment in marine phytoplankton. Cyclin-CDK and CaM/Ca2+ are essentially key regulators in control of cell cycle and signal transduction pathway, which has important values on both basic research and applied biotechnology. This paper reviews progress made in this research field, which involves the identification and characterization of cyclins and cell signal transduction system, cell cycle control mechanisms in marine phytoplankton cells, cell cycle proteins as a marker of a terminal event to estimate the growth rate of phytoplankton at the species level, cell cycle-dependent toxin production of toxic algae and cell cycle progression regulated by environmental factors.

  1. Cell proliferation alterations in Chlorella cells under stress conditions

    Energy Technology Data Exchange (ETDEWEB)

    Rioboo, Carmen [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); O' Connor, Jose Enrique [Laboratorio de Citomica, Unidad Mixta de Investigacion CIPF-UVEG, Centro de Investigacion Principe Felipe, Avda. Autopista del Saler, 16, 46013 Valencia (Spain); Prado, Raquel; Herrero, Concepcion [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain); Cid, Angeles, E-mail: cid@udc.es [Laboratorio de Microbiologia, Facultad de Ciencias, Universidad de A Coruna, Campus da Zapateira s/n, 15008 A Coruna (Spain)

    2009-09-14

    Very little is known about growth and proliferation in relation to the cell cycle regulation of algae. The lack of knowledge is even greater when referring to the potential toxic effects of pollutants on microalgal cell division. To assess the effect of terbutryn, a triazine herbicide, on the proliferation of the freshwater microalga Chlorella vulgaris three flow cytometric approaches were used: (1) in vivo cell division using 5-,6-carboxyfluorescein diacetate succinimidyl ester (CFSE) staining was measured, (2) the growth kinetics were determined by cytometric cell counting and (3) cell viability was evaluated with the membrane-impermeable double-stranded nucleic acid stain propidium iodide (PI). The results obtained in the growth kinetics study using CFSE to identify the microalgal cell progeny were consistent with those determined by cytometric cell counting. In all C. vulgaris cultures, each mother cell had undergone only one round of division through the 96 h of assay and the cell division occurred during the dark period. Cell division of the cultures exposed to the herbicide was asynchronous. Terbutryn altered the normal number of daughter cells (4 autospores) obtained from each mother cell. The number was only two in the cultures treated with 250 nM. The duration of the lag phase after the exposure to terbutryn could be dependent on the existence of a critical cell size to activate cytoplasmic division. Cell size, complexity and fluorescence of chlorophyll a of the microalgal cells presented a marked light/dark (day/night) cycle, except in the non-dividing 500 nM cultures, where terbutryn arrested cell division at the beginning of the cycle. Viability results showed that terbutryn has an algastatic effect in C. vulgaris cells at this concentration. The rapid and precise determination of cell proliferation by CFSE staining has allowed us to develop a model for assessing both the cell cycle of C. vulgaris and the in vivo effects of pollutants on growth and

  2. Cell-penetrating peptides: From mammalian to plant cells

    OpenAIRE

    Eudes, François; Chugh, Archana

    2008-01-01

    Internalization of cell-penetrating peptides, well described in mammalian cell system, has recently been reported in a range of plant cells by three independent groups. Despite fundamental differences between animal cell and plant cell composition, the CPP uptake pattern between the mammalian system and the plant system is very similar. Tat, Tat-2 pVEC and transportan internalisation is concentration dependent and non saturable, enhanced at low temperature (4°C), and receptor independent. The...

  3. Collective cell migration requires suppression of actomyosin at cell-cell contacts mediated by DDR1 and the cell polarity regulators Par3 and Par6

    OpenAIRE

    Hidalgo-Carcedo, Cristina; Hooper, Steven; Chaudhry, Shahid I.; Williamson, Peter; Harrington, Kevin; Leitinger, Birgit; Sahai, Erik

    2010-01-01

    Collective cell migration occurs in a range of contexts: cancer cells frequently invade in cohorts while retaining cell-cell junctions. Here we show that collective cancer cell invasion depends on reducing actomyosin contractility at sites of cell-cell contact. When actomyosin is not down-regulated at cell-cell contacts migrating cells lose cohesion. We provide a novel molecular mechanism for this down-regulation. Depletion of Discoidin Domain Receptor 1 (DDR1) blocks collective cancer cell i...

  4. Distinguishing between linear and exponential cell growth during the division cycle: Single-cell studies, cell-culture studies, and the object of cell-cycle research

    OpenAIRE

    Cooper Stephen

    2006-01-01

    Abstract Background Two approaches to understanding growth during the cell cycle are single-cell studies, where growth during the cell cycle of a single cell is measured, and cell-culture studies, where growth during the cell cycle of a large number of cells as an aggregate is analyzed. Mitchison has proposed that single-cell studies, because they show variations in cell growth patterns, are more suitable for understanding cell growth during the cell cycle, and should be preferred over cultur...

  5. The cell-cycle state of stem cells determines cell fate propensity.

    Science.gov (United States)

    Pauklin, Siim; Vallier, Ludovic

    2013-09-26

    Self-renewal and differentiation of stem cells are fundamentally associated with cell-cycle progression to enable tissue specification, organ homeostasis, and potentially tumorigenesis. However, technical challenges have impaired the study of the molecular interactions coordinating cell fate choice and cell-cycle progression. Here, we bypass these limitations by using the FUCCI reporter system in human pluripotent stem cells and show that their capacity of differentiation varies during the progression of their cell cycle. These mechanisms are governed by the cell-cycle regulators cyclin D1-3 that control differentiation signals such as the TGF-β-Smad2/3 pathway. Conversely, cell-cycle manipulation using a small molecule directs differentiation of hPSCs and provides an approach to generate cell types with a clinical interest. Our results demonstrate that cell fate decisions are tightly associated with the cell-cycle machinery and reveal insights in the mechanisms synchronizing differentiation and proliferation in developing tissues.

  6. [The cell theory. Progress in studies on cell-cell communications].

    Science.gov (United States)

    Brodskiĭ, V Ia

    2009-01-01

    Current data confirm the fundamental statement of the cell theory concerning the cell reproduction in a series of generations (omnis cellula e cellula). Cell communities or ensembles integrated by the signaling systems established in prokaryotes and protists and functioning in multicellular organisms including mammals are considered as the structural and functional unit of a multicellular organism. The cell is an elementary unit of life and basis of organism development and functioning. At the same time, the adult organism is not just a totality of cells. Multinucleated cells in some tissues, syncytial structure, and structural-functional units of organs are adaptations for optimal functioning of the multicellular organism and manifestations of cell-cell communications in development and definitive functioning. The cell theory was supplemented and developed by studies on cell-cell communications; however, these studies do not question the main generalizations of the theory.

  7. Macula densa cell signaling.

    Science.gov (United States)

    Bell, P Darwin; Lapointe, Jean Yves; Peti-Peterdi, János

    2003-01-01

    Macula densa cells are renal sensor elements that detect changes in distal tubular fluid composition and transmit signals to the glomerular vascular elements. This tubuloglomerular feedback mechanism plays an important role in regulating glomerular filtration rate and blood flow. Macula densa cells detect changes in luminal sodium chloride concentration through a complex series of ion transport-related intracellular events. NaCl entry via a Na:K:2Cl cotransporter and Cl exit through a basolateral channel lead to cell depolarization and increases in cytosolic calcium. Na/H exchange (NHE2) results in cell alkalization, whereas intracellular [Na] is regulated by an apically located H(Na)-K ATPase and not by the traditional basolateral Na:K ATPase. Communication from macula densa cells to the glomerular vascular elements involves ATP release across the macula densa basolateral membrane through a maxi-anion channel. The adaptation of multi-photon microscopy is providing new insights into macula densa-glomerular signaling.

  8. Regulating regulatory T cells.

    Science.gov (United States)

    Le, N T; Chao, N

    2007-01-01

    Regulatory T cells (Tregs) are a specialized subpopulation of T cells that act to suppress activation of other immune cells and thereby maintain immune system homeostasis, self-tolerance as well as control excessive response to foreign antigens. The mere concept of Tregs was the subject of significant controversy among immunologists for many years owing to the paucity of reliable markers for defining these cells and the ambiguity of the nature and molecular basis of suppressive phenomena. However, recent advances in the molecular characterization of this cell population have firmly established their existence and their vital role in the vertebrate immune system. Of interest, accumulating evidence from both humans and experimental animal models has implicated the involvement of Tregs in the development of graft-versus-host disease (GVHD). The demonstration that Tregs could separate GVHD from graft-versus-tumor (GVT) activity suggests that their immunosuppressive potential could be manipulated to reduce GVHD without detrimental consequence on GVT effect. Although a variety of T lymphocytes with suppressive capabilities have been reported, the two best-characterized subsets are the naturally arising, intrathymic-generated Tregs (natural Tregs) and the peripherally generated, inducible Tregs (inducible Tregs). This review summarizes our current knowledge of the generation, function and regulation of these two populations of Tregs during an immune response. Their role in the development of GVHD and their therapeutic potential for the prevention and treatment of GVHD will also be described.

  9. Fluorescent blood cell angiography

    Science.gov (United States)

    Ben-nun, Joshua; Constable, Ian J.

    1994-06-01

    Fluorescein angiography is currently the main method for evaluation of the retinal vascular patency. Ashton noted that capillary patency to the small fluorescein molecule may differ from that of the larger red blood cells. He concluded that fluorescein angiography is not able to demonstrate a developing stenosis, that might be the precipitating cause of a later capillary closure in various microvasculopathies. Sarelius et al have shown, in hamster cheek pouch and cremaster muscle, that fluorescently labeled erythrocytes in known concentrations can be used for the direct measurement of capillary flow parameters. The only assumption that this method relies on, is that the labeled cells are rheologically normal and therefore reflect the behavior of the total cell population. We have developed a new method for an in-vivo, real-time demonstration of the blood cell flow in the retinal capillary net. Based on the assumption presented by Sarelius et al, measurement and analysis of the retinal capillary blood cell flow is also possible from the results achieved by the new method.

  10. Carbon Nanotube Solar Cells

    Science.gov (United States)

    Klinger, Colin; Patel, Yogeshwari; Postma, Henk W. Ch.

    2012-01-01

    We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement. PMID:22655070

  11. Cell Culturing of Cytoskeleton

    Science.gov (United States)

    2004-01-01

    Biomedical research offers hope for a variety of medical problems, from diabetes to the replacement of damaged bone and tissues. Bioreactors, which are used to grow cells and tissue cultures, play a major role in such research and production efforts. Cell culturing, such as this bone cell culture, is an important part of biomedical research. The BioDyn payload includes a tissue engineering investigation. The commercial affiliate, Millenium Biologix, Inc., has been conducting bone implant experiments to better understand how synthetic bone can be used to treat bone-related illnesses and bone damaged in accidents. On STS-95, the BioDyn payload will include a bone cell culture aimed to help develop this commercial synthetic bone product. Millenium Biologix, Inc., is exploring the potential for making human bone implantable materials by seeding its proprietary artificial scaffold material with human bone cells. The product of this tissue engineering experiment using the Bioprocessing Modules (BPMs) on STS-95 is space-grown bone implants, which could have potential for dental implants, long bone grafts, and coating for orthopedic implants such as hip replacements.

  12. The Lamportian cell wall

    Energy Technology Data Exchange (ETDEWEB)

    Keiliszewski, M.; Lamport, D. (Michigan State Univ. Plant Research Lab., East Lansing (United States))

    1991-05-01

    The Lamportian Warp-Weft hypothesis suggests a cellulose-extensin interpenetrating network where extensin mechanically couples the load-bearing cellulose microfibrils in a wall matrix that is best described as a microcomposite. This model is based on data gathered from the extensin-rich walls of tomato and sycamore cell suspension culture, wherein extensin precursors are insolubilized into the wall by undefined crosslinks. The authors recent work with cell walls isolated from intact tissue as well as walls from suspension cultured cells of the graminaceous monocots maize and rice, the non-graminaceous monocot asparagus, the primitive herbaceous dicot sugar beet, and the gymnosperm Douglas Fir indicate that although extensins are ubiquitous to all plant species examined, they are not the major structural protein component of most walls examined. Amino acid analyses of intact and HF-treated walls shows a major component neither an HRGP, nor directly comparable to the glycine-rich wall proteins such as those associated with seed coat walls or the 67 mole% glycine-rich proteins cloned from petunia and soybean. Clearly, structural wall protein alternatives to extensin exist and any cell wall model must take that into account. If we assume that extracellular matrices are a priori network structures, then new Hypless' structural proteins in the maize cell wall raise questions about the sort of network these proteins create: the kinds of crosslinks involved; how they are formed; and the roles played by the small amounts of HRGPs.

  13. [Sickle cell pathophysiology].

    Science.gov (United States)

    Renaudier, P

    2014-11-01

    Sickle cell disease is associated with the inversion of one base pair (A = T → A = T). The sixth codon of the beta globin chain [GAA] becomes [GTA]. Accordingly, the sixth amino acid (glutamic acid, negatively charged) is replaced by valine, hydrophobic. A hydrophobic site is present on the outside of the HbS β chain. This incurs a hydrophobic bond with the phenylalanine in position 85 and leucine in position 88, in which outsource deoxy haemoglobin. Therefore, it creates a HbS polymer that deforms the red blood cell and causes vaso-occlusive crisis in the capillary venous pole. In this conventional design, the roles are added to the nitrogen monoxide and vascular tone, the increase in adhesion of red blood cells to the endothelium damage caused by red blood cells HbS: dehydration, senescence, formation of microvesicles. If these advances in our understanding of the pathophysiology have not yet had a clinical application, they will happen one day. It is therefore particularly important to pursue in France the network structure of sickle cell disease with a view to set up multicenter trials when the day comes.

  14. Carbon nanotube solar cells.

    Directory of Open Access Journals (Sweden)

    Colin Klinger

    Full Text Available We present proof-of-concept all-carbon solar cells. They are made of a photoactive side of predominantly semiconducting nanotubes for photoconversion and a counter electrode made of a natural mixture of carbon nanotubes or graphite, connected by a liquid electrolyte through a redox reaction. The cells do not require rare source materials such as In or Pt, nor high-grade semiconductor processing equipment, do not rely on dye for photoconversion and therefore do not bleach, and are easy to fabricate using a spray-paint technique. We observe that cells with a lower concentration of carbon nanotubes on the active semiconducting electrode perform better than cells with a higher concentration of nanotubes. This effect is contrary to the expectation that a larger number of nanotubes would lead to more photoconversion and therefore more power generation. We attribute this to the presence of metallic nanotubes that provide a short for photo-excited electrons, bypassing the load. We demonstrate optimization strategies that improve cell efficiency by orders of magnitude. Once it is possible to make semiconducting-only carbon nanotube films, that may provide the greatest efficiency improvement.

  15. Mesenchymal stem cell exosomes.

    Science.gov (United States)

    Lai, Ruenn Chai; Yeo, Ronne Wee Yeh; Lim, Sai Kiang

    2015-04-01

    MSCs are an extensively used cell type in clinical trials today. The initial rationale for their clinical testing was based on their differentiation potential. However, the lack of correlation between functional improvement and cell engraftment or differentiation at the site of injury has led to the proposal that MSCs exert their effects not through their differentiation potential but through their secreted product, more specifically, exosomes, a type of extracellular vesicle. We propose here that MSC exosomes function as an extension of MSC's biological role as tissue stromal support cells. Like their cell source, MSC exosomes help maintain tissue homeostasis for optimal tissue function. They target housekeeping biological processes that operate ubiquitously in all tissues and are critical in maintaining tissue homeostasis, enabling cells to recover critical cellular functions and begin repair and regeneration. This hypothesis provides a rationale for the therapeutic efficacy of MSCs and their secreted exosomes in a wide spectrum of diseases. Here, we give a brief introduction of the biogenesis of MSC exosomes, review their physiological functions and highlight some of their biochemical potential to illustrate how MSC exosomes could restore tissue homeostasis leading to tissue recovery and repair.

  16. Alkaline fuel cells applications

    Science.gov (United States)

    Kordesch, Karl; Hacker, Viktor; Gsellmann, Josef; Cifrain, Martin; Faleschini, Gottfried; Enzinger, Peter; Fankhauser, Robert; Ortner, Markus; Muhr, Michael; Aronson, Robert R.

    On the world-wide automobile market technical developments are increasingly determined by the dramatic restriction on emissions as well as the regimentation of fuel consumption by legislation. Therefore there is an increasing chance of a completely new technology breakthrough if it offers new opportunities, meeting the requirements of resource preservation and emission restrictions. Fuel cell technology offers the possibility to excel in today's motive power techniques in terms of environmental compatibility, consumer's profit, costs of maintenance and efficiency. The key question is economy. This will be decided by the costs of fuel cell systems if they are to be used as power generators for future electric vehicles. The alkaline hydrogen-air fuel cell system with circulating KOH electrolyte and low-cost catalysed carbon electrodes could be a promising alternative. Based on the experiences of Kordesch [K. Kordesch, Brennstoffbatterien, Springer, Wien, 1984, ISBN 3-387-81819-7; K. Kordesch, City car with H 2-air fuel cell and lead-battery, SAE Paper No. 719015, 6th IECEC, 1971], who operated a city car hybrid vehicle on public roads for 3 years in the early 1970s, improved air electrodes plus new variations of the bipolar stack assembly developed in Graz are investigated. Primary fuel choice will be a major issue until such time as cost-effective, on-board hydrogen storage is developed. Ammonia is an interesting option. The whole system, ammonia dissociator plus alkaline fuel cell (AFC), is characterised by a simple design and high efficiency.

  17. Stem cell organization in Arabidopsis

    NARCIS (Netherlands)

    Wendrich, J.R.

    2016-01-01

    Growth of plant tissues and organs depends on continuous production of new cells, by niches of stem cells. Stem cells typically divide to give rise to one differentiating daughter and one non-differentiating daughter. This constant process of self-renewal ensures that the niches of stem cells or mer

  18. Rare red blood cell abnormalities

    NARCIS (Netherlands)

    van Zwieten, R.

    2015-01-01

    The aim of this thesis is to give insight in the process of diagnosing rare red blood cell defects, to clarify the relation of a defect with cell function and to extend, in this respect, our knowledge about normal red cell function and biochemistry. It is possible to categorize different red cell ab

  19. Stem Cell Transplants (For Parents)

    Science.gov (United States)

    ... Teaching Kids to Be Smart About Social Media Stem Cell Transplants KidsHealth > For Parents > Stem Cell Transplants Print A A A What's in this ... Recovery Coping en español Trasplantes de células madre Stem cells are cells in the body that have the ...

  20. Peripheral T-Cell Lymphoma

    Science.gov (United States)

    Getting the Facts Peripheral T-Cell Lymphoma Overview Lymphoma is the most common blood cancer. The two main forms of lymphoma are Hodgkin lymphoma and ... develop into lymphomas: B-lymphocytes (B-cells) and T-lymphocytes (T-cells). Peripheral T-cell lymphoma (PTCL) ...