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Sample records for amnion cells

  1. Isolation and characterization of equine amnion mesenchymal stem cells

    OpenAIRE

    Coli, Alessandra; Nocchi, Francesca; Lamanna, Roberta; Iorio, Mariacarla; Lapi, Simone; Urciuoli, Patrizia; Scatena, Fabrizio; Giannessi, Elisabetta; Stornelli, Maria Rita; Passeri, Simona

    2011-01-01

    The amnion is a particular tissue whose cells show features of multipotent stem cells proposed for use in cellular therapy and regenerative medicine. From equine amnion collected after the foal birth we have isolated MSCs (mesenchymal stem cells), namely EAMSCs (equine amnion mesenchymal stem cells), from the mesoblastic layer. The cells were grown in α-MEM (α-modified minimum essential medium) and the effect of EGF (epidermal growth factor) supplementation was evaluated. To assess the growth...

  2. Maintenance of human amnion epithelial cell phenotype in pulmonary surfactant

    OpenAIRE

    McDonald, Courtney A.; Melville, Jacqueline M; Graeme R Polglase; Jenkin, Graham; Moss, Timothy JM

    2014-01-01

    Introduction Preterm newborns often require mechanical respiratory support that can result in ventilation-induced lung injury (VILI), despite exogenous surfactant treatment. Human amnion epithelial cells (hAECs) reduce lung inflammation and resultant abnormal lung development in preterm animals; co-administration with surfactant is a potential therapeutic strategy. We aimed to determine whether hAECs remain viable and maintain function after combination with surfactant. Methods hAECs were inc...

  3. Human amnion epithelial cells can be induced to differentiate into functional insulin-producing cells

    Institute of Scientific and Technical Information of China (English)

    Yanan Hou; Qin Huang; Tianjin Liu; Lihe Guo

    2008-01-01

    Pancreatic islet transplantation has demonstrated that long-term insulin independence may be achieved in patients suffering from diabetes mellitus type 1. However, limited availability of islet tissue means that new sources of insulinproducing cells that are responsive to glucose are required. Here, we show that human amnion epithelial cells (HAEC) can be induced to differentiate into functional insulinproducing cells in vitro. After induction of differentiation, HAEC expressed multiple pancreatic --cell genes, including insulin, pancreas duodenum homeobox-1, paired box gene 6,NK2 transcription factor-related locus 2, Islet 1, glucokinase,and glucose transporter-2, and released C-peptide in a glucose-regulated manner in response to other extracellular stimulations. The transplantation of induced HAEC into streptozotocin-induced diabetic C57 mice reversed hyperglycemia, restored body weight, and maintained euglycemia for 30 d. These findings indicated that HAEC may be a new source for cell replacement therapy in type 1 diabetes.

  4. Characterization of Side Cell Populations Obtained from Human Amnion Mesenchymal Cells

    Institute of Scientific and Technical Information of China (English)

    LI Ning; PIAO Zhengfu; Mamoru Kobayashi; Koji Sasaki; DING Shu-qin; Aiko Kikuchi; Isao Kamo; Norio Sakuragawa

    2009-01-01

    Human amnion mesenchymal cells (AMCs) contain multipotent cells. To enrich such multipotent stem cells, we applied to AMCs the new method for the isolation of side population (SP) cells used for the enrichment of multipotent stem cells from many tissues. We succeeded in obtaining SP cells from AMCs (AMC-SP cells). AMC-SP cells were found in 0.2% of AMCs, irrespective of the length of pregnant period, ranging from 37 to 40 weeks. Cell cycle analyses uggested that AMC-SP cells belonged to a cell population that proliferated very slowly and/or was in a quiescent state in the amniotic membrane. Upon culturing, they proliferated with 40 to 80 cell doublings. However, they did not form colonies in a soft agarose culture, whereas HepG2 cells, representative human hepatoma cells formed many large colonies. These results suggest that AMC-SP cells that have considerable value for the use of regenerative medicine can be managed safely in vitro.

  5. Prostaglandin E2 regulation of amnion cell vascular endothelial growth factor expression: relationship with intramembranous absorption rate in fetal sheep.

    Science.gov (United States)

    Cheung, Cecilia Y; Beardall, Michael K; Anderson, Debra F; Brace, Robert A

    2014-08-01

    We hypothesized that prostaglandin E2 (PGE2) stimulates amniotic fluid transport across the amnion by upregulating vascular endothelial growth factor (VEGF) expression in amnion cells and that amniotic PGE2 concentration correlates positively with intramembranous (IM) absorption rate in fetal sheep. The effects of PGE2 at a range of concentrations on VEGF 164 and caveolin-1 gene expressions were analyzed in cultured ovine amnion cells. IM absorption rate, amniotic fluid (AF) volume, and PGE2 concentration in AF were determined in late-gestation fetal sheep during control conditions, isovolumic fetal urine replacement (low IM absorption rate), or intra-amniotic fluid infusion (high IM absorption rate). In ovine amnion cells, PGE2 induced dose- and time-dependent increases in VEGF 164 mRNA levels and reduced caveolin-1 mRNA and protein levels. VEGF receptor blockade abolished the caveolin-1 response, while minimally affecting the VEGF response to PGE2. In sheep fetuses, urine replacement reduced amniotic PGE2 concentration by 58%, decreased IM absorption rate by half, and doubled AF volume (P amniotic fluid infusion increased IM absorption rate and AF volume (P amniotic PGE2 concentration was unchanged. Neither IM absorption rate nor AF volume correlated with amniotic PGE2 concentration under each experimental condition. Although PGE2 at micromolar concentrations induced dose-dependent responses in VEGF and caveolin-1 gene expression in cultured amnion cells consistent with a role of PGE2 in activating VEGF to mediate AF transport across the amnion, amniotic PGE2 at physiological nanomolar concentrations does not appear to regulate IM absorption rate or AF volume.

  6. Derivation and characterization of human embryonic stem cells on human amnion epithelial cells.

    Science.gov (United States)

    Lai, Dongmei; Wang, Yongwei; Sun, Jian; Chen, Yifei; Li, Ting; Wu, Yi; Guo, Lihe; Wei, Chunsheng

    2015-05-07

    Culture conditions that support the growth of undifferentiated human embryonic stem cells (hESCs) have already been established using primary human amnion epithelial cells (hAECs) as an alternative to traditional mitotically inactivated mouse embryonic fibroblasts (MEFs). In the present work, inner cell masses (ICM) were isolated from frozen embryos obtained as donations from couples undergoing in vitro fertilization (IVF) treatment and four new hESC lines were derived using hAECs as feeder cells. This feeder system was able to support continuous growth of what were, according to their domed shape and markers, undifferentiated naïve-like hESCs. Their pluripotent potential were also demonstrated by embryoid bodies developing to the expected three germ layers in vitro and the productions of teratoma in vivo. The cell lines retained their karyotypic integrity for over 35 passages. Transmission electron microscopy (TEM) indicated that these newly derived hESCs consisted mostly of undifferentiated cells with large nuclei and scanty cytoplasm. The new hESCs cultured on hAECs showed distinct undifferentiated characteristics in comparison to hESCs of the same passage maintained on MEFs. This type of optimized culture system may provide a useful platform for establishing clinical-grade hESCs and assessing the undifferentiated potential of hESCs.

  7. Isolation of Human Amnion Epithelial Cells According to Current Good Manufacturing Procedures.

    Science.gov (United States)

    Gramignoli, Roberto; Srinivasan, Raghuraman C; Kannisto, Kristina; Strom, Stephen C

    2016-01-01

    Different cell types can be isolated from human placental tissues, and some have been reported to retain phenotypic plasticity and characteristics that make them a promising source of cells for regenerative medicine. Among these are human amnion epithelial cells (hAECs). Adoption of current good manufacturing practices (cGMP) and enhanced quality control is essential when isolating hAECs in order to deliver a safe and effective cellular product for clinical purposes. This unit describes a detailed protocol for selective isolation of hAECs from human term placenta with little to no contamination by other cell types. A method for characterizing the heterogeneity of the hAEC suspension is also provided. The resulting cell product will be useful for clinical as well as basic research applications. © 2016 by John Wiley & Sons, Inc. PMID:27171794

  8. Mesenchymal stem cells from amnion and amniotic fluid in the bovine.

    Science.gov (United States)

    Corradetti, B; Meucci, A; Bizzaro, D; Cremonesi, F; Lange Consiglio, A

    2013-04-01

    Amnion and amniotic fluid (AF) are noncontroversial and inexhaustible sources of mesenchymal stem cells (MSCs) that can be harvested noninvasively at low cost. As in humans, also in veterinary field, presumptive stem cells derived from these tissues reveal as promising candidates for disease treatment, specifically for their plasticity, their reduced immunogenicity, and high anti-inflammatory potential. The aim of this work is to obtain and characterize, for the first time in bovine species, presumptive MSCs from the epithelial portion of the amnion (AECs) and from the AF (AF-MSCs) to be used for clinical applications. AECs display a polygonal morphology, whereas AF-MSCs exhibit a fibroblastic-like morphology only starting from the second passage, being heterogeneous during the primary culture. For both lines, the proliferative ability has been found constant over the ten passages studied and AECs show a statistically lower (P<0.05) doubling time with respect to AF-MSCs. AECs express MSC-specific markers (ITGB1 (CD29), CD44, ALCAM (CD166), ENG (CD105), and NT5E (CD73)) from P1 to P3; in AF-MSCs, only ITGB1, CD44, and ALCAM mRNAs are detected; NT5E is expressed from P2 and ENG has not been found at any passage. AF-MSCs and AECs are positive for the pluripotent markers (POU5F1 (OCT4) and MYC (c-Myc)) and lack of the hematopoietic markers. When appropriately induced, both cell lines are capable of differentiating into ectodermal and mesodermal lineages. This study contributes to reinforce the emerging importance of these cells as ideal tools in veterinary medicine. A deeper evaluation of the immunological properties needs to be performed in order to better understand their role in cellular therapy.

  9. Amnion-Epithelial-Cell-Derived Exosomes Demonstrate Physiologic State of Cell under Oxidative Stress.

    Science.gov (United States)

    Sheller, Samantha; Papaconstantinou, John; Urrabaz-Garza, Rheanna; Richardson, Lauren; Saade, George; Salomon, Carlos; Menon, Ramkumar

    2016-01-01

    At term, the signals of fetal maturity and feto-placental tissue aging prompt uterine readiness for delivery by transitioning quiescent myometrium to an active stage. It is still unclear how the signals reach the distant myometrium. Exosomes are a specific type of extracellular vesicle (EVs) that transport molecular signals between cells, and are released from a wide range of cells, including the maternal and fetal cells. In this study, we hypothesize that i) exosomes act as carriers of signals in utero-placental compartments and ii) exosomes reflect the physiologic status of the origin cells. The primary aims of this study were to determine exosomal contents in exosomes derived from primary amnion epithelial cells (AEC). We also determined the effect of oxidative stress on AEC derived exosomal cargo contents. AEC were isolated from amniotic membrane obtained from normal, term, not in labor placentae at delivery, and culture under standard conditions. Oxidative stress was induced using cigarette smoke extract for 48 hours. AEC-conditioned media were collected and exosomes isolated by differential centrifugations. Both growth conditions (normal and oxidative stress induced) produced cup shaped exosomes of around 50 nm, expressed exosomes enriched markers, such as CD9, CD63, CD81 and HSC70, embryonic stem cell marker Nanog, and contained similar amounts of cell free AEC DNA. Using confocal microscopy, the colocalization of histone (H) 3, heat shock protein (HSP) 70 and activated form of pro-senescence and term parturition associated marker p38 mitogen activated protein kinase (MAPK) (P-p38 MAPK) co-localized with exosome enrich marker CD9. HSP70 and P-p38 MAPK were significantly higher in exosomes from AEC grown under oxidative stress conditions than standard conditions (pmass spectrometry and bioinformatics analysis identified 221 different proteins involved in immunomodulatory response and cell-to-cell communication. This study determined AEC exosome

  10. Amnion-Epithelial-Cell-Derived Exosomes Demonstrate Physiologic State of Cell under Oxidative Stress

    Science.gov (United States)

    Sheller, Samantha; Papaconstantinou, John; Urrabaz-Garza, Rheanna; Richardson, Lauren; Saade, George; Salomon, Carlos; Menon, Ramkumar

    2016-01-01

    At term, the signals of fetal maturity and feto-placental tissue aging prompt uterine readiness for delivery by transitioning quiescent myometrium to an active stage. It is still unclear how the signals reach the distant myometrium. Exosomes are a specific type of extracellular vesicle (EVs) that transport molecular signals between cells, and are released from a wide range of cells, including the maternal and fetal cells. In this study, we hypothesize that i) exosomes act as carriers of signals in utero-placental compartments and ii) exosomes reflect the physiologic status of the origin cells. The primary aims of this study were to determine exosomal contents in exosomes derived from primary amnion epithelial cells (AEC). We also determined the effect of oxidative stress on AEC derived exosomal cargo contents. AEC were isolated from amniotic membrane obtained from normal, term, not in labor placentae at delivery, and culture under standard conditions. Oxidative stress was induced using cigarette smoke extract for 48 hours. AEC-conditioned media were collected and exosomes isolated by differential centrifugations. Both growth conditions (normal and oxidative stress induced) produced cup shaped exosomes of around 50 nm, expressed exosomes enriched markers, such as CD9, CD63, CD81 and HSC70, embryonic stem cell marker Nanog, and contained similar amounts of cell free AEC DNA. Using confocal microscopy, the colocalization of histone (H) 3, heat shock protein (HSP) 70 and activated form of pro-senescence and term parturition associated marker p38 mitogen activated protein kinase (MAPK) (P-p38 MAPK) co-localized with exosome enrich marker CD9. HSP70 and P-p38 MAPK were significantly higher in exosomes from AEC grown under oxidative stress conditions than standard conditions (pexosome characteristics and their cargo reflected the physiologic status of the cell of origin and suggests that AEC-derived exosomal p38 MAPK plays a major role in determining the fate of pregnancy

  11. Human amnion epithelial cells induced to express functional cystic fibrosis transmembrane conductance regulator.

    Directory of Open Access Journals (Sweden)

    Sean V Murphy

    Full Text Available Cystic fibrosis, an autosomal recessive disorder caused by a mutation in a gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR, remains a leading cause of childhood respiratory morbidity and mortality. The respiratory consequences of cystic fibrosis include the generation of thick, tenacious mucus that impairs lung clearance, predisposing the individual to repeated and persistent infections, progressive lung damage and shortened lifespan. Currently there is no cure for cystic fibrosis. With this in mind, we investigated the ability of human amnion epithelial cells (hAECs to express functional CFTR. We found that hAECs formed 3-dimensional structures and expressed the CFTR gene and protein after culture in Small Airway Growth Medium (SAGM. We also observed a polarized CFTR distribution on the membrane of hAECs cultured in SAGM, similar to that observed in polarized airway cells in vivo. Further, hAECs induced to express CFTR possessed functional iodide/chloride (I(-/Cl(- ion channels that were inhibited by the CFTR-inhibitor CFTR-172, indicating the presence of functional CFTR ion channels. These data suggest that hAECs may be a promising source for the development of a cellular therapy for cystic fibrosis.

  12. Human amnion mesenchymal stem cells promote proliferation and osteogenic differentiation in human bone marrow mesenchymal stem cells.

    Science.gov (United States)

    Wang, Yuli; Yin, Ying; Jiang, Fei; Chen, Ning

    2015-02-01

    Human amnion mesenchymal stem cells (HAMSCs) can be obtained from human amniotic membrane, a highly abundant and readily available tissue. HAMSC sources present fewer ethical issues, have low immunogenicity, anti-inflammatory properties, considerable advantageous characteristics, and are considered an attractive potential treatment material in the field of regenerative medicine. We used a co-culture system to determine whether HAMSCs could promote osteogenesis in human bone marrow mesenchymal stem cells (HBMSCs). We isolated HAMSCs from discarded amnion samples and collected them using pancreatin/collagenase digestion. We cultured HAMSCs and HBMSCSs in basal medium. Activity of alkaline phosphatase (ALP), an early osteogenesis marker, was increased in the co-culture system compared to the control single cultures, which we also confirmed by ALP staining. We used immunofluorescence testing to investigate the effects of co-culturing with HAMSCs on HBMSC proliferation, which revealed that the co-culturing enhanced EdU expression in HBMSCs. Western blotting and quantitative real-time PCR indicated that co-culturing promoted osteogenesis in HBMSCs. Furthermore, Alizarin red S staining revealed that extracellular matrix calcium levels in mineralized nodule formation produced by the co-cultures were higher than that in the controls. Using the same co-culture system, we further observed the effects of HAMSCs on osteogenic differentiation in primary osteoblasts by Western blotting, which better addressed the mechanism for HAMSCs in bone regeneration. The results showed HAMSCs are osteogenic and not only play a role in promoting HBMSC proliferation and osteogenic differentiation but also in osteoblasts, laying the foundation for new regenerative medicine methods.

  13. Amnion and Chorion Membranes: Potential Stem Cell Reservoir with Wide Applications in Periodontics

    OpenAIRE

    Akanksha Gupta; Suresh D. Kedige; Kanu Jain

    2015-01-01

    The periodontal therapy usually aims at elimination of disease causing bacteria and resolution of inflammation. It involves either resective or regenerative surgery to resolve the inflammation associated defects. Over the years, several methods have been used for achievement of periodontal regeneration. One of the oldest biomaterials used for scaffolds is the fetal membrane. The amniotic membranes of developing embryo, that is, amnion (innermost lining) and chorion (a layer next to it), have ...

  14. Stem cell therapy to protect and repair the developing brain: a review of mechanisms of action of cord blood and amnion epithelial derived cells.

    Science.gov (United States)

    Castillo-Melendez, Margie; Yawno, Tamara; Jenkin, Graham; Miller, Suzanne L

    2013-10-24

    In the research, clinical, and wider community there is great interest in the use of stem cells to reduce the progression, or indeed repair brain injury. Perinatal brain injury may result from acute or chronic insults sustained during fetal development, during the process of birth, or in the newborn period. The most readily identifiable outcome of perinatal brain injury is cerebral palsy, however, this is just one consequence in a spectrum of mild to severe neurological deficits. As we review, there are now clinical trials taking place worldwide targeting cerebral palsy with stem cell therapies. It will likely be many years before strong evidence-based results emerge from these trials. With such trials underway, it is both appropriate and timely to address the physiological basis for the efficacy of stem-like cells in preventing damage to, or regenerating, the newborn brain. Appropriate experimental animal models are best placed to deliver this information. Cell availability, the potential for immunological rejection, ethical, and logistical considerations, together with the propensity for native cells to form teratomas, make it unlikely that embryonic or fetal stem cells will be practical. Fortunately, these issues do not pertain to the use of human amnion epithelial cells (hAECs), or umbilical cord blood (UCB) stem cells that are readily and economically obtained from the placenta and umbilical cord discarded at birth. These cells have the potential for transplantation to the newborn where brain injury is diagnosed or even suspected. We will explore the novel characteristics of hAECs and undifferentiated UCB cells, as well as UCB-derived endothelial progenitor cells (EPCs) and mesenchymal stem cells (MSCs), and how immunomodulation and anti-inflammatory properties are principal mechanisms of action that are common to these cells, and which in turn may ameliorate the cerebral hypoxia and inflammation that are final pathways in the pathogenesis of perinatal brain

  15. Stem cell therapy to protect and repair the developing brain: a review of mechanisms of action of cord blood and amnion epithelial derived cells

    Directory of Open Access Journals (Sweden)

    Margie eCastillo-Melendez

    2013-10-01

    Full Text Available In the research, clinical and wider community there is great interest in the use of stem cells to reduce the progression, or indeed repair brain injury. Perinatal brain injury may result from acute or chronic insults sustained during fetal development, during the process of birth, or in the newborn period. The most readily identifiable outcome of perinatal brain injury is cerebral palsy, however this is just one consequence in a spectrum of mild to severe neurological deficits. As we review, there are now clinical trials taking place worldwide targeting cerebral palsy with stem cell therapies. It will likely be many years before strong evidence-based results emerge from these trials. With such trials underway, it is both appropriate and timely to address the physiological basis for the efficacy of stem-like cells in preventing damage to, or regenerating, the newborn brain. Appropriate experimental animal models are best placed to deliver this information. Cell availability, the potential for immunological rejection, ethical and logistical considerations, together with the propensity for native cells to form terratomas, make it unlikely that embryonic or fetal stem cells will be practical. Fortunately, these issues do not pertain to the use of human amnion epithelial cells (hAECs, or umbilical cord blood (UCB stem cells that are readily and economically obtained from the placenta and umbilical cord discarded at birth. These cells have the potential for transplantation to the newborn where brain injury is diagnosed or even suspected. We will explore the novel characteristics of hAECs and undifferentiated UCB cells, as well as UCB-derived endothelial progenitor cells and mesenchymal stem cells, and how immunomodulation and anti-inflammatory properties are principal mechanisms of action that are common to these cells, and which in turn may ameliorate the cerebral hypoxia and inflammation that are final pathways in the pathogenesis of perinatal brain

  16. Contribution of aquaporin 9 and multidrug resistance-associated protein 2 to differential sensitivity to arsenite between primary cultured chorion and amnion cells prepared from human fetal membranes

    Energy Technology Data Exchange (ETDEWEB)

    Yoshino, Yuta [Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Yuan, Bo, E-mail: yuanbo@toyaku.ac.jp [Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, 1550 4th St, RH584E Box 2911 San Francisco, CA 94158-2911 (United States); Kaise, Toshikazu [Laboratory of Environmental Chemodynamics, School of Life Sciences, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Takeichi, Makoto [Yoneyama Maternity Hospital, 2-12 Shin-machi, Hachioji, Tokyo 192-0065 (Japan); Tanaka, Sachiko; Hirano, Toshihiko [Department of Clinical Pharmacology, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan); Kroetz, Deanna L. [Department of Bioengineering and Therapeutic Sciences, University of California San Francisco, 1550 4th St, RH584E Box 2911 San Francisco, CA 94158-2911 (United States); Toyoda, Hiroo [Department of Clinical Molecular Genetics, School of Pharmacy, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo 192-0392 (Japan)

    2011-12-15

    Arsenic trioxide (arsenite, As{sup III}) has shown a remarkable clinical efficacy, whereas its side effects are still a serious concern. Therefore, it is critical to understand the effects of As{sup III} on human-derived normal cells for revealing the mechanisms underlying these side effects. We examined the effects of As{sup III} on primary cultured chorion (C) and amnion (A) cells prepared from human fetal membranes. A significant dose-dependent As{sup III}-mediated cytotoxicity was observed in the C-cells accompanied with an increase of lactate dehydrogenase (LDH) release. Higher concentrations of As{sup III} were required for the A-cells to show cytotoxicity and LDH release, suggesting that the C-cells were more sensitive to As{sup III} than the A-cells. The expression levels of aquaporin 9 (AQP9) were approximately 2 times higher in the C-cells than those in the A-cells. Both intracellular arsenic accumulation and its cytotoxicity in the C-cells were significantly abrogated by sorbitol, a competitive AQP9 inhibitor, in a dose-dependent manner. The protein expression levels of multidrug resistance-associated protein (MRP) 2 were downregulated by As{sup III} in the C-cells, but not in the A-cells. No significant differences in the expression levels of MRP1 were observed between C- and A-cells. The protein expression of P-glycoprotein (P-gp) was hardly detected in both cells, although a detectable amount of its mRNA was observed. Cyclosporine A, a broad-spectrum inhibitor for ABC transporters, and MK571, a MRP inhibitor, but not PGP-4008, a P-gp specific inhibitor, potently sensitized both cells to As{sup III}-mediated cytotoxicity. These results suggest that AQP9 and MRP2 are involved in controlling arsenic accumulation in these normal cells, which then contribute to differential sensitivity to As{sup III} cytotoxicity between these cells. -- Highlights: Black-Right-Pointing-Pointer Examination of effect of As{sup III} on primary cultured chorion (C) and amnion

  17. Contribution of aquaporin 9 and multidrug resistance-associated protein 2 to differential sensitivity to arsenite between primary cultured chorion and amnion cells prepared from human fetal membranes.

    Science.gov (United States)

    Yoshino, Yuta; Yuan, Bo; Kaise, Toshikazu; Takeichi, Makoto; Tanaka, Sachiko; Hirano, Toshihiko; Kroetz, Deanna L; Toyoda, Hiroo

    2011-12-01

    Arsenic trioxide (arsenite, As(III)) has shown a remarkable clinical efficacy, whereas its side effects are still a serious concern. Therefore, it is critical to understand the effects of As(III) on human-derived normal cells for revealing the mechanisms underlying these side effects. We examined the effects of As(III) on primary cultured chorion (C) and amnion (A) cells prepared from human fetal membranes. A significant dose-dependent As(III)-mediated cytotoxicity was observed in the C-cells accompanied with an increase of lactate dehydrogenase (LDH) release. Higher concentrations of As(III) were required for the A-cells to show cytotoxicity and LDH release, suggesting that the C-cells were more sensitive to As(III) than the A-cells. The expression levels of aquaporin 9 (AQP9) were approximately 2 times higher in the C-cells than those in the A-cells. Both intracellular arsenic accumulation and its cytotoxicity in the C-cells were significantly abrogated by sorbitol, a competitive AQP9 inhibitor, in a dose-dependent manner. The protein expression levels of multidrug resistance-associated protein (MRP) 2 were downregulated by As(III) in the C-cells, but not in the A-cells. No significant differences in the expression levels of MRP1 were observed between C- and A-cells. The protein expression of P-glycoprotein (P-gp) was hardly detected in both cells, although a detectable amount of its mRNA was observed. Cyclosporine A, a broad-spectrum inhibitor for ABC transporters, and MK571, a MRP inhibitor, but not PGP-4008, a P-gp specific inhibitor, potently sensitized both cells to As(III)-mediated cytotoxicity. These results suggest that AQP9 and MRP2 are involved in controlling arsenic accumulation in these normal cells, which then contribute to differential sensitivity to As(III) cytotoxicity between these cells.

  18. Neuronal-like differentiation of single versus multiple treatments with human amnion-derived mesenchymal stem cells induced by basic fibroblast growth factor

    Institute of Scientific and Technical Information of China (English)

    Hongliang Jiao; Fangxia Guan; Xiang Hu; Jianbin Li; Hong Shan; Wei Li; Jun Li; Ying Du; Bo Yang; Yunfan Zhou

    2009-01-01

    BACKGROUND: Cultures from multiple portions of umbilical cord blood mesenchymal stem cells have been shown to undergo more rapid proliferation and attachment than single portions. OBJECTIVE: To observe growth of basic fibroblast growth factor (bFGF)-induced cultures of human amnion-derived mesenchymal stem cells (AMSCs) and differentiation into neuronal-like cells. DESIGN, TIME AND SETTING: Comparative observation. The study was performed at the Laboratory of Microbiology and Immunology, Basic Medical School of Zhengzhou University from January to May 2008.METHODS: Amnia from full-term, uterine-incision delivery were donated by 12 healthy women. AMSCs were obtained by cell separation and culture techniques, and were passaged and induced by bFGF. From the third passage, a total of 1 mL AMSCs, at a density of 1.0 ×10 4/mL, was separately harvested from six samples, which served as group A. A total of 1 mL AMSCs, at a density of 1.0×10 4 /mL, was harvested separately from the remaining six samples, which served as group B. A total of 0.5 mL from the six samples of group A and 0.5 mL from the six samples of group B were combined to form group C. MAIN OUTCOME MEASURES: Differences in cell quantity among the three groups were compared by cell quantification and 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT)analysis. Expression of a glial cell marker, neuron-specific enolase, and nestin was detected in the three groups by immunocytochemistry. RESULTS: Cell quantification and MTT analysis of live cells, as well as AMSC absorbance, were significantly greater in group C compared with groups A and B at 18 days of culture (P<0.05), and no significant difference was observed between groups A and B. Glial fibrillary acidic protein, neuron-specific enolase, and nestin were expressed in all groups following bFGF induction. CONCLUSION: Mixed AMSC cultures promoted proliferation, and bFGF-induced AMSCs differentiated into neuronal-like cells.

  19. Smad5 determines murine amnion fate through the control of bone morphogenetic protein expression and signalling levels.

    Science.gov (United States)

    Bosman, Erika A; Lawson, Kirstie A; Debruyn, Joke; Beek, Lisette; Francis, Annick; Schoonjans, Luc; Huylebroeck, Danny; Zwijsen, An

    2006-09-01

    Smad5 is an intracellular mediator of bone morphogenetic protein (Bmp) signalling. It is essential for primordial germ cell (PGC) development, for the development of the allantois and for amnion closure, as demonstrated by loss of Bmp signalling. By contrast, the appearance of ectopic PGC-like cells and regionalized ectopic vasculogenesis and haematopoiesis in thickened Smad5(m1/m1) amnion are amnion defects that have not been associated with loss of Bmp signalling components. We show that defects in amnion and allantois can already be detected at embryonic day (E) 7.5 in Smad5 mutant mice. However, ectopic Oct4-positive (Oct4(+)) and alkaline phosphatase-positive (AP(+)) cells appear suddenly in thickened amnion at E8.5, and at a remote distance from the allantois and posterior primitive streak, suggesting a change of fate in situ. These ectopic Oct4(+), AP(+) cells appear to be Stella negative and hence cannot be called bona fide PGCs. We demonstrate a robust upregulation of Bmp2 and Bmp4 expression, as well as of Erk and Smad activity, in the Smad5 mutant amnion. The ectopic expression of several Bmp target genes in different domains and the regionalized presence of cells of several Bmp-sensitive lineages in the mutant amnion suggest that different levels of Bmp signalling may determine cell fate. Injection of rBMP4 in the exocoelom of wild-type embryos can induce thickening of amnion, mimicking the early amnion phenotype in Smad5 mutants. These results support a model in which loss of Smad5 results paradoxically in gain of Bmp function defects in the amnion. PMID:16887830

  20. Comprehensive two-dimensional gel protein databases offer a global approach to the analysis of human cells: the transformed amnion cells (AMA) master database and its link to genome DNA sequence data

    DEFF Research Database (Denmark)

    Celis, J E; Gesser, B; Rasmussen, H H;

    1990-01-01

    A total of 3430 polypeptides (2592 cellular; 838 secreted) from transformed human amnion cells (AMA) labeled with [35S]methionine were separated and recorded using computer-aided two-dimensional (2-D) gel electrophoresis. A master 2-D gel database of cellular protein information that includes both......, mitochondria, Golgi, ribosomes, intermediate filaments, microfilaments and microtubules), levels in fetal human tissues, partial protein sequences (containing information on 48 human proteins microsequenced so far), cell cycle-regulated proteins, proteins sensitive to interferons alpha, beta, and gamma, heat......-specific proteins, to microsequence them and store the information in the database, to identify the corresponding genes, to search for homology with previously characterized proteins and to study the function of groups of proteins (pathways, organelles, etc.) that exhibit interesting regulatory properties...

  1. Ex vivo expansion of hematopoietic stem- and progenitor cells from cord blood in coculture with mesenchymal stroma cells from amnion, chorion, Wharton's jelly, amniotic fluid, cord blood, and bone marrow.

    Science.gov (United States)

    Klein, Caroline; Strobel, Julian; Zingsem, Jürgen; Richter, Richard H; Goecke, Tamme W; Beckmann, Matthias W; Eckstein, Reinhold; Weisbach, Volker

    2013-12-01

    In most cases, the amount of hematopoietic stem and progenitor cells (HSPCs) in a single cord blood (CB) unit is not sufficient for allogenic transplantation of adults. Therefore, two CB units are usually required. The ex vivo expansion of HSPCs from CB in coculture with mesenchymal stroma cells (MSCs) might be an alternative. It was investigated, whether bone marrow-derived MSCs, which have to be obtained in an invasive procedure, introduce a further donor and increases the risk of transmissible infectious diseases for the patient can be replaced by MSCs from amnion, chorion, Wharton's jelly, amniotic fluid, and CB, which can be isolated from placental tissue which is readily available when CB is sampled. In a two-step ex vivo coculture mononuclear cells from cryopreserved CB were cultured with different MSC-feederlayers in a medium supplemented with cytokines (stem cell factor, thrombopoietin [TPO], and granulocyte colony-stimulating factor). Expansion rates were analyzed as well, by long-term culture-initiating cell (LTC-IC) and colony-forming unit (CFU) assays, as by measuring CD34(+)- and CD45(+)-cells. Due to the comparably low number of 5×10(2) to 1×10(4) CD34(+)-cells per cm(2) MSC-monolayer, we observed comparably high expansion rates from 80 to 391,000 for CFU, 70 to 313,000 for CD34(+)-, and 200 to 352,000 for CD45(+)-cells. Expansion of LTC-IC was partly observed. Compared to the literature, we found a better expansion rate of CD34(+)-cells with MSCs from all different sources. This is probably due to the comparably low number of 5×10(2) to 1×10 CD34(+)-cells per cm(2) MSC-monolayer we used. Comparably, high expansion rates were observed from 80 to 391,000 for CFUs, 70 to 313,000 for CD34(+)-, and 200 to 352,000 for CD45(+)-cells. However, the expansion of CD34(+)-cells was significantly more effective with MSCs from bone marrow compared to MSCs from amnion, chorion, and Wharton's jelly. The comparison of MSCs from bone marrow with MSCs from CB and

  2. The Use of Amnion-Derived Cellular Cytokine Solution to Improve Healing in Acute and Chronic Wound Models

    OpenAIRE

    Franz, Michael G.; Payne, Wyatt G.; Xing, Liyu; Naidu, D. K; Salas, R. E; Marshall, Vivienne S.; Trumpower, C. J; Smith, Charlotte A; Steed, David L.; Robson, M. C.

    2008-01-01

    Objective: Growth factors demonstrate mixed results improving wound healing. Amnion-derived multipotent cells release physiologic levels of growth factors and tissue inhibitors of metalloproteinases. This solution was tested in models of acute and chronic wound healing. Methods: Acute model: Sprague-Dawley rats underwent laparotomy incisions. The midline fascia was primed with phosphate-buffered saline, unconditioned media, or amnion-derived cellular cytokine suspension prior to incision. Bre...

  3. Nuclear factor kappa B activation occurs in the amnion prior to labour onset and modulates the expression of numerous labour associated genes.

    Directory of Open Access Journals (Sweden)

    Sheri Lim

    Full Text Available BACKGROUND: Prior to the onset of human labour there is an increase in the synthesis of prostaglandins, cytokines and chemokines in the fetal membranes, particular the amnion. This is associated with activation of the transcription factor nuclear factor kappa B (NFκB. In this study we characterised the level of NFκB activity in amnion epithelial cells as a measure of amnion activation in samples collected from women undergoing caesarean section at 39 weeks gestation prior to the onset of labour. METHODOLOGY/PRINCIPAL FINDINGS: We found that a proportion of women exhibit low or moderate NFκB activity while other women exhibit high levels of NFκB activity (n = 12. This activation process does not appear to involve classical pathways of NFκB activation but rather is correlated with an increase in nuclear p65-Rel-B dimers. To identify the full range of genes upregulated in association with amnion activation, microarray analysis was performed on carefully characterised non-activated amnion (n = 3 samples and compared to activated samples (n = 3. A total of 919 genes were upregulated in response to amnion activation including numerous inflammatory genes such cyclooxygenase-2 (COX-2, 44-fold, interleukin 8 (IL-8, 6-fold, IL-1 receptor accessory protein (IL-1RAP, 4.5-fold, thrombospondin 1 (TSP-1, 3-fold and, unexpectedly, oxytocin receptor (OTR, 24-fold. Ingenuity Pathway Analysis of the microarray data reveal the two main gene networks activated concurrently with amnion activation are i cell death, cancer and morphology and ii cell cycle, embryonic development and tissue development. CONCLUSIONS/SIGNIFICANCE: Our results indicate that assessment of amnion NFκB activation is critical for accurate sample classification and subsequent interpretation of data. Collectively, our data suggest amnion activation is largely an inflammatory event that occurs in the amnion epithelial layer as a prelude to the onset of labour.

  4. Gamma radiation sterilized amnion: use in ophthalmology

    Energy Technology Data Exchange (ETDEWEB)

    Martinez P, M. E. [ININ, Carretera Mexico-Toluca s/n, Ocoyoacac 52750, Estado de Mexico (Mexico); Leon T, Y. [Hospital General Regional 220, IMSS, Paseo Tollocan No. 620, Col. Vertice, Toluca 50150, Estado de Mexico (Mexico); Vazquez M, L., E-mail: esther.martinez@inin.gob.m [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06720 Mexico D. F. (Mexico)

    2010-10-15

    Amnion processed at the Radio sterilized Tissue Bank at the National Institute of Nuclear Research, sterilized with {sup 60}Co gamma radiation, have been used in Mexico since 2005 either as a graft to replace the damaged ocular surface, or as a patch to prevent unwanted inflammatory reactions. Patients from the Hospital General de Mexico (HGM) and Instituto Mexicano del Seguro Social (IMSS), suffering diverse pathologies such as keratoconjunctivitis; recurrent pterygium associated with symblepharon; corneal neuro trophic ulcers, chemical and thermal burns, and corneal thinning s, had been successfully treated with irradiated amnion. In the HGM, a clinical prospective study on lesions of the ocular surface of 17 eyes from 15 patients, affected with the above mentioned pathologies, was successful in 88.2%. The results have proven to be excellent as much for cosmetic purposes as for functional ones. Without the treatment, the patients could have suffered a healing after-effect or loss of sight. At IMSS, a controlled clinical randomized trial with 108 eyes from 100 patients, affected with primary nasal pterygium, was performed in 2009. These eyes were treated with radio sterilized amnion and intraoperative mitomycin C to prevent recurrence after excision of the primary pterygium. The preliminary results do not shown adverse reaction, inflammation and pain were significantly reduced radio sterilized amnion also offer security because they do no express antigens HLA-A, B or Dr and the sterile irradiated tissue do not provoke rejection or transmit an infective disease. (Author)

  5. Aquaporins in ovine amnion: responses to altered amniotic fluid volumes and intramembranous absorption rates.

    Science.gov (United States)

    Cheung, Cecilia Y; Anderson, Debra F; Brace, Robert A

    2016-07-01

    Aquaporins (AQPs) are transmembrane channel proteins that facilitate rapid water movement across cell membranes. In amniotic membrane, the AQP-facilitated transfer of water across amnion cells has been proposed as a mechanism for amniotic fluid volume (AFV) regulation. To investigate whether AQPs modulate AFV by altering intramembranous absorption (IMA) rate, we tested the hypothesis that AQP gene expression in the amnion is positively correlated with IMA rate during experimental conditions when IMA rate and AFV are modified over a wide range. The relative abundances of AQP1, AQP3, AQP8, AQP9, and AQP11 mRNA and protein were determined in the amnion of 16 late-gestation ovine fetuses subjected to 2 days of control conditions, urine drainage, urine replacement, or intraamniotic fluid infusion. AQP mRNA levels were determined by RT-qPCR and proteins by western immunoblot. Under control conditions, mRNA levels among the five AQPs differed more than 20-fold. During experimental treatments, mean IMA rate in the experimental groups ranged from 100 ± 120 mL/day to 1370 ± 270 mL/day. The mRNA levels of the five AQPs did not change from control and were not correlated with IMA rates. The protein levels of AQP1 were positively correlated with IMA rates (r(2) = 38%, P = 0.01) while the remaining four AQPs were not. These findings demonstrate that five AQPs are differentially expressed in ovine amnion. Our study supports the hypothesis that AQP1 may play a positive role in regulating the rate of fluid transfer across the amnion, thereby participating in the dynamic regulation of AFV.

  6. The dynamic expression of extraembryonic marker genes in the beetle Tribolium castaneum reveals the complexity of serosa and amnion formation in a short germ insect.

    Science.gov (United States)

    Sharma, Rahul; Beermann, Anke; Schröder, Reinhard

    2013-12-01

    Most insect embryos develop with two distinct extraembryonic membranes, the serosa and the amnion. In the insect beetle Tribolium the early origin of the serosa within the anterior blastoderm is well established but the origin of the amnion is still debated. It is not known whether this tissue develops from a blastodermal precursor or originates de novo later from embryonic tissue during embryogenesis. We undertook an in-depth analysis of the spatio-temporal expression pattern profile of important extraembryonic membrane marker genes with emphasis on early blastoderm development in Tribolium. The amnion marker iroquois (Tc-iro) was found co-expressed with the serosa marker zerknüllt1 (Tc-zen1) during early blastoderm formation in an anterior cap domain. This domain later resolved into two adjacent domains that likely represent the precursors of the serosa and the amnion. In addition, we found the hindsight ortholog in Tribolium (Tc-hnt) to be a serosa-specific marker. Surprisingly, decapentaplegic (Tc-dpp) expression was not seen as a symmetric cap domain but detected asymmetrically first along the DV- and later also along the AP-axis. Moreover, we found a previously undescribed domain of phosphorylated MAD (pMAD) protein in anterior ventral serosal cells. This is the first study showing that the anterior-lateral part of the amnion originates from the anterior blastoderm while the precursor of the dorsal amnion develops later de novo from a dorsal-posterior region within the differentiated blastoderm.

  7. The mixed cultures and neuronal-like differentiation of human amnion-derived mesenchymal stem cells%人羊膜间充质干细胞混合培养及向神经样细胞分化

    Institute of Scientific and Technical Information of China (English)

    焦红亮; 王晓宁; 孙剑瑞; 李建斌; 关方霞; 杨波

    2013-01-01

    目的 观察羊膜间充质干细胞(HAMs)可诱导分化为神经样细胞混合培养的生长以及经碱性成纤维细胞生长因子(bFGF)诱导HAMs向神经样细胞分化.方法 采用细胞分离和培养技术获取HAMs,分离HAMs后传代培养,加入bFGF诱导分化.当细胞传至第3代时,随机取培养的6份HAMs(半量)为A组,6份HAMs(半量)为B组,将A、B组各剩余的半量HAMs混合为C组.3组细胞密度均为1.0 x 107/L.以活细胞计数和噻唑蓝(MTT)比色法比较3组细胞扩增数量,免疫组织化学法检测HAMs胶质纤维酸性蛋白(GFAP)、神经元特异性烯醇化酶(NSE)、巢蛋白(Nestin)的表达.以活细胞计数和MTT比色法比较3组细胞扩增数量,免疫组织化学检测HAMs神经胶质细胞标志物、神经元特异性烯醇化酶和巢蛋白的表达.结果 活细胞计数结果显示,第18天A组HAMs为(4.80±1.49)×104个,B组HAMs为(5.00±1.75) xl04个,C组HAMs为(8.90±3.46)×104个.MTT比色检测结果均显示,第18天A组HAMs为0.242±3.408,B组HAMs为0.245±5.226,C组HAMs为0.321 ±1.321(P <0.05).经bFGF诱导后均表达GFAP 、NSE和Nestin.结论 混合HAMs之间有互相促增殖作用,HAMs具有较强的可塑性,经bFGF诱导的HAMs可表达GFAP、NSE和Nestin.%Objective To observe growth of basic fibroblast growth factor (bFGF)-induced cultures of human amnion-derived mesenchymal stem cells (HAMs) and differentiation into neuronal-like cells.Comparative observation.Methods Amnia from full-term,uterine-incision delivery were donated by 12 healthy women.HAMs were obtained by cell separation and culture techniques,and were passaged and induced by bFGF.From the third passage,a total of 1 ml HAMs,at a density of 1.0 × 107/L,was separately harvested from six samples,which served as group A.A total of 1 ml HAMs,at a density of 1.0 × 107/L,was harvested separately from the remaining six samples,which served as group B.A total of 0.5 ml from the six samples of group A and 0.5 ml from the

  8. Genome-Wide Analysis of DNA Methylation in Human Amnion

    Directory of Open Access Journals (Sweden)

    Jinsil Kim

    2013-01-01

    Full Text Available The amnion is a specialized tissue in contact with the amniotic fluid, which is in a constantly changing state. To investigate the importance of epigenetic events in this tissue in the physiology and pathophysiology of pregnancy, we performed genome-wide DNA methylation profiling of human amnion from term (with and without labor and preterm deliveries. Using the Illumina Infinium HumanMethylation27 BeadChip, we identified genes exhibiting differential methylation associated with normal labor and preterm birth. Functional analysis of the differentially methylated genes revealed biologically relevant enriched gene sets. Bisulfite sequencing analysis of the promoter region of the oxytocin receptor (OXTR gene detected two CpG dinucleotides showing significant methylation differences among the three groups of samples. Hypermethylation of the CpG island of the solute carrier family 30 member 3 (SLC30A3 gene in preterm amnion was confirmed by methylation-specific PCR. This work provides preliminary evidence that DNA methylation changes in the amnion may be at least partially involved in the physiological process of labor and the etiology of preterm birth and suggests that DNA methylation profiles, in combination with other biological data, may provide valuable insight into the mechanisms underlying normal and pathological pregnancies.

  9. The effect of gamma irradiation on injectable human amnion collagen

    Energy Technology Data Exchange (ETDEWEB)

    Liu, B.C.; Harrell, R.; Davis, R.H.; Dresden, M.H.; Spira, M. (Institute of Occupational Medicine, Beijing (China))

    1989-08-01

    The effect of gamma irradiation on the physicochemical properties of injectable human amnion collagen was investigated. Pepsin-extracted human amnion collagen was purified, reconstituted, and irradiated with varying doses of gamma irradiation (0.25 Mrads to 2.5 Mrads). Gamma irradiation had a significant impact on the physical characteristics of the collagen. The neutral solubility of collagen in PBS at 45{degrees}C was decreased from 100% for the nonirradiated control sample to 16% for the 2.5 Mrads irradiated sample. SDS polyacrylamide gel electrophoresis also demonstrated the dose-dependent effect of gamma irradiation on collagen cross-links. Electron microscopic observation revealed that even at low irradiation dose (0.25 Mrads), collagen fibril diameter increased. The average diameter was 50 nm for nonirradiated control fibrils, while 4.4% of the irradiated collagen fibrils had a diameter greater than 100 nm. Irradiated collagen showed little evidence of damage. Well-preserved cross-striations were found in collagen fibrils at all doses of irradiation. Native amnion collagen irradiated with gamma rays demonstrated a slight increase in resistance to collagenase degradation compared with nonirradiated native collagen samples. Increased resistance to collagenase did not correlate with increasing irradiation dose. After 30 min of incubation at 37{degrees}C, both irradiated and nonirradiated collagen was completely digested by collagenase. However, gamma-irradiated collagen did become more sensitive to hydrolysis by trypsin. The higher the irradiation doses used, the greater sensitivity to trypsin was observed. At 0.25 Mrads irradiation only a slight increase was found. No marked differences in amino acid composition were noted among the high dose irradiated, low dose irradiated and control amnion collagen.

  10. Nuclear microanalysis of the human amnion: A study of ionic cellular exchanges

    Science.gov (United States)

    Razafindrabe, L.; Moretto, Ph.; Llabador, Y.; Simonoff, M.; Bara, M.; Guiet-Bara, A.

    1995-09-01

    The epithelial cells of the human amniotic membrane have been extensively studied by electrophysiologists with the aim of elucidating the mechanisms of transmembrane ionic transfers. In order to provide complementary information about this model, nuclear microanalysis was performed using the CENBG ion microbeam. Quantitative mapping of the human amnion was carried out and the distributions of most mono- and divalent ions involved in cellular pathways (Na +, Mg 2+, Cl -, Ca 2+) were determined. The ionic cellular content was also compared, before and after incubation in a Hanks' physiological fluid and the resultant ions transfers were determined. The aim of this paper is to expose the advances of this experimental model, more particularly after the development of simulation programs which improved the accuracy of PIXE analysis in the measurement of low energy X-rays emitters. Statistically significant results can now be extracted and can be explained taking into account the results of previous electrophysiological experiments.

  11. Propolis and amnion reepithelialise second-degree burns in rats.

    Science.gov (United States)

    Pessolato, Alicia Greyce Turatti; Martins, Daniele dos Santos; Ambrósio, Carlos Eduardo; Mançanares, Celina Almeida Furlanetto; de Carvalho, Ana Flávia

    2011-11-01

    Burns are serious consequences of trauma in terms of both imminent mortality and prolonged periods of morbidity. They are often accompanied by unsatisfactory cosmetic as well as functional and psychological outcomes. These complications emphasise the need for stronger efforts in achieving greater diversity and effectiveness in the treatment of skin burns. This study aimed to verify the effectiveness of gross and microscopic epidermal and dermal responses in the process of regenerative repair or healing of burns in rats that were treated either daily with 5% propolis ointment or by autologous amnion graft. Second-degree burns were inflicted in the neck region of female rats by contact with a hot metal (at 130 °C) for 5 s. Propolis treatment accelerated the process of tissue repair and led to decreased local inflammation, which indicates that treatment with propolis was successful in the initial period (7 days) and stimulated the production of collagen fibre (assessed by morphometry) in all the periods evaluated (14 and 21 days). Amnion treatment inhibited local inflammation (assessed macroscopically), stimulated local epithelial regeneration (assessed microscopically) and stimulated the production of collagen fibre (assessed by morphometry) in the days following burn. These treatments offer new therapeutic strategies for treating severe skin burns; these strategies may allow the minimisation of scar formation, a more rapid return of function and, ultimately, a better quality of life for burn patients.

  12. A discrete network model to represent the deformation behavior of human amnion.

    Science.gov (United States)

    Mauri, Arabella; Hopf, Raoul; Ehret, Alexander E; Picu, Catalin R; Mazza, Edoardo

    2016-05-01

    A discrete network model (DNM) to represent the mechanical behavior of the human amnion is proposed. The amnion is modeled as randomly distributed points interconnected with connector elements representing collagen crosslinks and fiber segments, respectively. This DNM is computationally efficient and allows simulations with large domains. A representative set of parameters has been selected to reproduce the uniaxial tension-stretch and kinematic responses of the amnion. Good agreement is found between the predicted and measured equibiaxial tension-stretch curves. Although the model represents the amnion phenomenologically, model parameters are physically motivated and their effect on the tension-stretch and in-plane kinematic responses is discussed. The model is used to investigate the local response in the near field of a circular hole, revealing that the kinematic response at the circular free boundaries leads to compaction and strong alignment of the network at the border of the defect. PMID:26700570

  13. A roentgenographic assessment of regenerative efficacy of bioactive Gengigel® in conjunction with amnion membrane in grade II furcation defect

    Directory of Open Access Journals (Sweden)

    S Harveen Kalra

    2015-01-01

    Full Text Available Background: Nowadays, techniques are being developed to guide and instruct the specialized cellular components of the periodontium to participate in the regenerative process. This approach of reconstruction makes use of understanding of the development of the periodontium and the cellular processes that are involved. Hyaluronic acid is a naturally occurring non-sulfated high molecular weight glycosaminoglycan that forms a critical component of the extracellular matrix and contributes significantly to tissue hydrodynamics, cell migration, and proliferation. Hence, its administration to periodontal wound sites could achieve comparable beneficial effects in periodontal tissue regeneration. Hence, the purpose of the present case report was to assess roentgenographically, the regenerative capacity of Gengigel® in conjunction with bioactive amnion guided tissue regeneration (GTR membrane in a patient with Grade II furcation defect. Case Presentation: A patient complained of bleeding gums from the lower back tooth region, reportedly found Grade II furcation in the lower right mandibular first molar. After Phase, I therapy, Gengigel® along with bioactive amnion membrane was placed in the furcation area during the surgical phase. Roentgenographic assessment was done at 4 months and 6 months postoperatively. It resulted in complete defect-fill and loss of radiolucency at 6 months. Conclusion: Surgical placement of Gengigel® along with amnion membrane in the furcation defect can significantly improve the periodontal defect morphology.

  14. Halofuginone- and Chitosan-Coated Amnion Membranes Demonstrate Improved Abdominal Adhesion Prevention

    Directory of Open Access Journals (Sweden)

    Scott Washburn

    2010-01-01

    Full Text Available Our objective was to determine whether coating the amniotic membrane with halofuginone, a type 1 collagen synthase inhibitor, with or without the hemostasis-inducing substance chitosan, reduced the number and severity of adhesions in the rat uterine horn injury model. Sixty retired breeder Sprague-Dawley rats underwent midline laparotomy and a zone of ischemia was created in the left uterine horn of each animal. Rats were randomized to one of six treatment groups: (1 untreated control, (2 oxidized regenerated cellulose (Interceed® (ORC, (3 plain amnion, (4 amnion coated on both sides with 0.5% solution of halofuginone (HAH, (5 amnion coated on one side with 0.5% halofuginone and on the other side with chitosan (CAH, or (6 amnion coated on both sides with chitosan (CAC. The zone of ischemia in each left uterine horn was wrapped in each treatment. Rats were sacrificed 2 weeks after laparotomy, and adhesions were counted and scored for severity. Data were analyzed using Chi square and a p <0.05 was considered significant. Our results showed that there were no differences in the percentage of animals with adhesions in the untreated, ORC, plain amnion, or CAC groups. No adhesions formed in any animal in the HAH group and only 14% of the animals developed adhesions to the uterine horn in the CAH group (p < 0.05. The percentage of animals with moderate and severe adhesions did not differ between untreated controls and the ORC groups, but were significantly reduced in all four of the amnion groups: plain amnion, HAH, CAH, and CAC (p < 0.05. Amnion coated with halofuginone alone or in combination with chitosan reduced the percentage of animals with adhesions, as well as the percentage of animals with moderate and severe adhesions compared to untreated controls and the ORC group in the rat uterine horn injury model. Amnion alone or coated with chitosan reduced the percentage of rats with moderate and severe adhesions, but not the percentage of rats with

  15. Initiation of bone and amnion banking in Turkey

    International Nuclear Information System (INIS)

    There is a growing demand in Turkey for human tissue to use in surgery and wound healing. However, our country does not have facilities for local production of tissue grafts and generally depends on imported products. Under a multi-year project initiated in 1997, the International Atomic Energy Agency (IAEA) has provided main equipment for tissue processing and experts on tissue banking as well as training on tissue processing methods. In this presentation, information on various stages of the project implementation is given. Details of lay out for the process laboratories and list of equipment supplied by the Agency and purchased locally are also given. Donor selection and testing, processing procedures for bone and amnion, setting up product design, implementation of quality system and radiation sterilisation are described briefly. Quality procedures included preparation of quality manual, Standard Operating Procedures (SOP), record forms, document control, non-conformance and corrective actions, training records, equipment maintenance and calibration are all in line with Good Manufacturing Practice (GMP) standards. Clinical applications of tissue grafts and medico-legal position of organ and tissue donation in Turkey are also discussed briefly

  16. 人羊膜间充质干细胞培养上清液对人成纤维细胞生物学功能的影响%Effects of culture supernatant of human amnion mesenchymal stem cells on biological characteristics of human fibroblasts

    Institute of Scientific and Technical Information of China (English)

    吴骐而; 吕璐; 辛海明; 罗亮; 童亚林; 莫永亮; 岳毅刚

    2016-01-01

    Objective To investigate the effects of culture supernatant of human amnion mesenchymal stem cells (hAMSCs-CS) on biological characteristics of human fibroblasts.Methods (1) hAMSCs were isolated from deprecated human fresh amnion tissue of placenta and then sub-cultured.The morphology of hAMSCs on culture day 3 and hAMSCs of the third passage were observed with inverted phase contrast microscope.(2) Two batches of hAMSCs of the third passage were obtained,then the expression of vimentin of cells was observed with immunofluorescence method,and the expression of cell surface marker CD90,CD73,CD105,and CD45 was detected by flow cytometer.(3) hAMSCs-CS of the third passage at culture hour 72 were collected,and the content of insulin-like growth factor Ⅰ (IGF-Ⅰ),vascular endothelial growth factor (VEGF),epidermal growth factor (EGF),and basic fibroblast growth factor (bFGF) were detected by enzyme-linked immunosorbent assay.(4) Hunan fibroblasts were isolated from deprecated human fresh prepuce tissue of circumcision and then sub-cultured.Human fibroblasts of the third passage were used in the following experiments.Cells were divided into blank control group and 10%,30%,50%,and 70% hAMSCs-CS groups according to the random number table (the same grouping method below),with 48 wells in each group.Cells in blank control group were cultured with DMEM/F12 medium containing 2% fetal bovine serum (FBS),while cells in the latter 4 groups were cultured with DMEM/F12 medium containing corresponding volume fraction of hAMSCs-CS and 2% FBS.The proliferation activity of cells was detected by cell counting kit 8 and microplate reader at culture hour 12,24,48,and 72,respectively,and corresponding volume fraction of hAMSCs-CS which causing the best proliferation activity of human fibroblasts was used in the following experiments.(5) Human fibroblasts were divided into blank control group and 50% hAMSCs-CS group and treated as in (4),with 4 wells in each group,at post

  17. 自体角膜缘干细胞移植与羊膜移植治疗翼状胬肉的对比研究%Comparative Study on treatment of pterygium with auto-corneallimbus stem cell transplantation and amnion transplantation

    Institute of Scientific and Technical Information of China (English)

    蔡春梅; 付湘媛; 张晶; 邓江稳

    2011-01-01

    目的 比较自体角膜缘干细胞移植、羊膜移植和单纯翼状胬肉切除三种手术方式治疗翼状胬肉的治愈及复发情况.设计回顾性病例系列.研究对象自2007年8月至2010年8月在解放军第二炮兵总医院眼科应用上述三种手术方法治疗并有随访记录的翼状胬肉患者193例(217眼).方法 根据手术方法的不同,将193例(217眼)翼状胬肉患者分为3组:角膜缘干细胞移植组(A组)73例81眼;羊膜移植组(B组)54例63眼;单纯翼状胬肉切除组(C组)66例73眼.术后平均随访1年(12.2±2.3)月,观察并比较三组患者的治疗效果、复发率和并发症情况.主要指标复发率和并发症.结果 随访期间,A组复发4眼,复发率为4.94%;B组复发10眼,复发率为15.9%;C组复发23眼,复发率为31.5%(A与B组、A与C组、B与C组相比,x2值分别为4.828、18.746、4.498,P值分别为0.028、0.000、0.034).随访期内,A组未发生睑球粘连,B组有1眼(1.59%)出现睑球粘连,C组有8眼(10.96%)出现睑球粘连.结论 与单纯翼状胬肉切除术和羊膜移植术相比,自体角膜缘干细胞移植治疗翼状胬肉并发症少、复发率低,是治疗翼状胬肉较好的手法方法.%Objective To compare the curative and recurrent situation for the treatment of pterygium among three operative methods (simple excision of prerygium,combined excision of pterygium with auto-corneallimbus stem cell transplantation, and combined excision of pterygium with amnion transplantation). Design Retrospective case series. Participants 193 cases (217 eyes )with pterygium,who underwent the operation in The Second Artillery General Hospital of PLA from Aug. 2007 to Aug. 2010. Methods 193 cases (217 eyes ) with pterygium were divided into 3 groups according to the operative method: combined excision of pterygium with auto-comedlimbus stem cell transplantation (group A )73 cases (81 eyes), combined excision of pterygium with amnjon transplantation (group B) 54 cases (63

  18. Safety Profile of Amnion-Derived Cellular Cytokine Solution (ACCS) Following Topical Skin Application in Patients Receiving Breast Radiotherapy

    OpenAIRE

    Trombetta, Mark; Julian, Thomas B.; Wickerham, D. Lawrence; Steed, David L.

    2015-01-01

    Objective: To establish a safety profile for amnion-derived cellular cytokine solution following topical application in patients undergoing whole breast radiotherapy for breast cancer. Materials and Methods: Twenty female patients with early-stage breast cancer were enrolled in 2 separate cohorts of an institutional review board–approved phase I protocol. Cohort 1 consisted of 10 patients who received topical amnion-derived cellular cytokine solution to the breast immediately following the fi...

  19. 人羊膜匀浆上清液对脂多糖致伤的大鼠肺微血管内皮细胞增殖及分泌炎症因子的影响%Effect of supernatant of human amnion homogenate on lipopolysaccharide induced pulmonary microvascular endotheli-al cells injury and their proliferation and expression of proinflammatory factors in rats

    Institute of Scientific and Technical Information of China (English)

    陈云鹏; 朱富军; 龚震宇; 辛海明; 王磊; 童亚林; 刘亮; 吕璐; 莫永亮; 詹球; 阳齐琼; 梁静

    2015-01-01

    长因子、细胞因子,对 LPS致伤的 RPMVECs增殖具有促进作用,并减少致伤后炎症因子分泌。%Objective:To investigate the protective effect of supernatant of human amnion homogenate (hAHS)on proliferation and expression of proinflammatory mediators by lipopolysaccharide (LPS)induced inj ured pulmonary microvascular endothelial cells of rats (RPMVECs).Methods:hAHS was prepared from fresh human amnion. The total protein content and the content of epithelial growth factor (EGF),basic fibroblast growth factor (bFGF), vascular endothelial growth factor (VEGF),interleukin-4 (IL-4),IL-10,angiogenin-1 (Ang-1),humanβ-defensin2 (HBD2)of hAHS were determined with Coomassie blue staining and ELISA. The effect of 0,10%,15%, 20%,25% hAHS on cell proliferation activity of RPMVECs was respectively determined with MTT assay,in or-der to determine the optimal concentration of hAHS on promoting RPMVECs proliferation. According to different co-culture conditions,RPMVECs were randomly divided into 4 groups:group N (cultured with 10%FBS+DMEM/F12),group A(10%FBS+DMEM/F12+15%hAHS),group B (10%FBS+DMEM/F12+LPS),and group C (10%FBS+DMEM/F12+15%hAHS+LPS). At 0,12,24,48,72 hours after culturing with the corre-sponding medium of each group,optical density values (A values)of each group were determined respectively with MTT assay to determine the proliferation activity,and the contents of IL-6,IL-8,TNF-αlevels in the culture su-pernates were also determined by ELISA at 6,8,10,12 and 24 hours. Results:The total protein concentration of hAHS was (725.125±12.625)mg/L,and levels of EGF,bFGF,VEGF,IL-4,IL-10,Ang-1,HDB2 were re-spectively(504.785±4.665)ng/L,(4.426±0.138)ng/L,(0.185±0.006)ng/L,(25.650±4.104)ng/L,(13.733 ±2.197)ng/L,(15.561±0.496)ng/L,(4.763±0.714)ng/L.10%-20% hAHS was shown to promote prolifer-ation of RPMVECs,and 15% hAHS,and the best result was observed on 7 and 9 days. The proliferation rate of RPMVECs in 25% hAHS group at 7,9 and 11 days was lower than those in the 0%hAHS group (P<0

  20. Human amnion membrane matrix as a substratum for axonal regeneration in the central nervous system.

    Science.gov (United States)

    Gage, F H; Blaker, S N; Davis, G E; Engvall, E; Varon, S; Manthorpe, M

    1988-01-01

    Human Amnion Membrane Matrix (HAMM) was used as a substratum for the regeneration of neuronal axons in the central nervous system. A large piece of HAMM was bound to nitrocellulose paper (NCP) as a supporting material, and cut into small strips. Aspirative lesions of the fimbria-fornix were made in adult rats leaving a cavity separating the septum from the hippocampus. In the same operation a small piece of HAMM-NCP was placed into the cavity with one end abutting the axotomized septum and the other end abutting the denervated hippocampus. At times between 2 weeks and 3 months after surgery the brains of the animals were examined histologically for 1) host response to the implant; 2) maintenance of HAMM-NCP in the originally implanted orientation; 3) growth of acetylcholinesterase (AChE)-positive fibers on the HAMM; 4) growth of the AChE-positive fibers into the denervated hippocampus; and 5) non-neuronal cells on the HAMM. The NCP remained in place over the 3-month period. In most cases the HAMM and NCP remained apposed and caused no greater reaction in the brain beyond that created in response to the aspirative lesion alone. AChE-positive fibers grew out from the septum onto the HAMM by 2 weeks, and by 8 weeks more extensive growth was observed on the HAMM. By 8-weeks, AChE fibers could be clearly seen coming off the membrane and entering the host hippocampus. By double-labelling for the basement membrane side of the HAMM (using anti-human laminin antibodies) and for cholinergic fibers (using AChE histochemistry) in the same sections, it was possible to see fibers clearly growing on the laminin-positive side of the HAMM but little or no growth on the opposing laminin-negative stromal side. The most important variables for extensive growth appeared to be the accurate placement of the implant and the amount of time following the lesions. The placement of the matrix on NCP prior to implantation in the brain made it easier to orient the membrane between the septum

  1. Use of gamma-irradiated amnion as a biological dressing in the management of radiation induced ulcers

    International Nuclear Information System (INIS)

    Full text: The treatment of moist skin desquamation (ulceration) following radiation therapy focuses on promoting healing, preventing microbial infections, protecting from mechanical trauma and providing pain relief. Various dressings like hydrocolloid, 1% gentian violet and other topical applications are routinely used. This study evaluated the use of freeze-dried, irradiated amnion from the Tata Memorial Hospital Tissue Bank in the management of radiation ulcers from 2001 to 2007. During this period, 2095 amnion dressings were used in 554 patients (238 male and 316 female). The ulcer was cleaned with normal saline and the amnion applied directly on the affected area. No topical antibiotics were used. The ulcer sites were in the regions of the groin and perianal area (40.79%), head and neck (30.50%), breast and axilla (18.59%), limbs (5.78%), chest (2.70%) and back (1.62%). Healing occurred within 4 days to 14 days using a single application of amnion in 291 patients (52.53%), 2 dressings in 129 patients (23.28%) and 3 dressings in 74 patients (13.36%). The remaining 60 patients (10.83%) required four or more dressings which were used over a period of a month. The amnion dressing was found to be convenient to apply and adhered well to the affected areas without the use of any adhesives unlike with routine hydro-colloid dressing. This was particularly advantageous in sites with irregular contours such as the groin and perianal areas and the head and neck regions (71.29%). Patients experienced almost immediate pain relief and the need for analgesics was reduced. In the majority of patients healing occurred earlier than was usually obtained with routine dressings. The amnion dressing proved to be advantageous over co ventional dressings because of its convenience of use and cost effectiveness due to shorter duration of healing, fewer dressing changes and diminished use of analgesics and antibiotics. (Author)

  2. Comparison of structural changes in skin and amnion tissue grafts for transplantation induced by gamma and electron beam irradiation for sterilization.

    Science.gov (United States)

    Mrázová, H; Koller, J; Kubišová, K; Fujeríková, G; Klincová, E; Babál, P

    2016-06-01

    Sterilization is an important step in the preparation of biological material for transplantation. The aim of the study is to compare morphological changes in three types of biological tissues induced by different doses of gamma and electron beam radiation. Frozen biological tissues (porcine skin xenografts, human skin allografts and human amnion) were irradiated with different doses of gamma rays (12.5, 25, 35, 50 kGy) and electron beam (15, 25, 50 kGy). Not irradiated specimens served as controls. The tissue samples were then thawn and fixed in 10 % formalin, processed by routine paraffin technique and stained with hematoxylin and eosin, alcian blue at pH 2.5, orcein, periodic acid Schiff reaction, phosphotungstic acid hematoxylin, Sirius red and silver impregnation. The staining with hematoxylin and eosin showed vacuolar cytoplasmic changes of epidermal cells mainly in the samples of xenografts irradiated by the lowest doses of gamma and electron beam radiation. The staining with orcein revealed damage of fine elastic fibers in the xenograft dermis at the dose of 25 kGy of both radiation types. Disintegration of epithelial basement membrane, especially in the xenografts, was induced by the dose of 15 kGy of electron beam radiation. The silver impregnation disclosed nuclear chromatin condensation mainly in human amnion at the lowest doses of both radiation types and disintegration of the fine collagen fibers in the papillary dermis induced by the lowest dose of electron beam and by the higher doses of gamma radiation. Irradiation by both, gamma rays and the electron beam, causes similar changes on cells and extracellular matrix, with significant damage of the basement membrane and of the fine and elastic and collagen fibers in the papillary dermis, the last caused already by low dose electron beam radiation. PMID:26649556

  3. Transplantation of human amnion-derived mesenchymal stem cells alleviates ischemia-reperfusion-induced acute lung injury after cardiopulmonary bypass%人羊膜间充质干细胞移植减轻体外循环再灌注肺损伤

    Institute of Scientific and Technical Information of China (English)

    强勇; 梁贵友; 余丽梅; 齐斌; 高振宇

    2016-01-01

    BACKGROUND:In recent years, mesenchymal stem cels exhibit a good prospect in organ or tissue repair and therefore, and therefore, cel transplantation based on mesenchymal stem cel plasticity can promote cel regeneration and functional recovery from lung injury after cardiopulmonary bypass. OBJECTIVE:To investigate the effects of human amnion-derived mesenchymal stem cels (hAMSCs) transplantation on ischemia-reperfusion-induced acute lung injury in dogs after cardiopulmonary bypassand its mechanism for regulating inflammatory cytokines. METHODS:Eighteen adult healthy mongrel dogs were randomly divided into three groups (n=6 per group): black group (cardiopulmonary bypass with 1 mL physiological saline injectionvia the femoral vein without blocking the aorta), control group (cardiopulmonary bypass with blocking the aorta for 1 hour and then opening the aorta for 15 minutes plus 1 mL physiological saline injectionvia the femoral vein), experiment group (cardiopulmonary bypass with blocking the aorta for 1 hour and then opening the aorta for 15 minutes plus femoral vein injection of 1 mL physiological saline containing 2×107 hAMSCs). Arterial blood samples of 2 mL were taken to calculate oxygenation index and respiratory index before cardiopulmonary bypass (T1), 15 minutes (T2), 1 hour (T3), 2 hours (T4), 3 hours (T5) after opening the aorta. 8 mL intravenous blood samples were taken to detect the serum tumor necrosis factor α, matrix metaloproteinase-9, interleukin-8 and interleukin-10 by ELISA. Meanwhile, western blot assay was used to detect the expression of nuclear factor-κB in lung tissues, and histopathological changes of lung tissues observed under optical microscope. RESULTS AND CONCLUSION:Compared with the control group, the oxygenation index was significantly increased in the experimental group at 2 and 3 hours after transplantation, and the respiratory index was remarkably decreased at 1, 2, 3 hours after transplantation. Compared with the control group

  4. Versuche zur elektrophysiologischen Charakterisierung des Amnions von Hühnerembryonen ( Gallus gallus f. domestica ) mit Hilfe der Ussing - Kammer - Methode

    OpenAIRE

    Blasius, Heiner

    2010-01-01

    It was the aim of this study to characterize the chick amnion electrophysiologically using “Ussing” - chamber experiments. To this end, it was first necessary to establish an appropriate time window for the examinations. According to literature data and preliminary experimental data, incubation days D9 and D10 were chosen. Furthermore, an adequate preparation technique was established. The experimental buffer system was assembled according to literature data. After clarifying these met...

  5. Angiogenic properties of dehydrated human amnion/chorion allografts: therapeutic potential for soft tissue repair and regeneration

    OpenAIRE

    Koob, Thomas J; Lim, Jeremy J.; Massee, Michelle; Zabek, Nicole; Rennert, Robert; Gurtner, Geoffrey; Li, William W

    2014-01-01

    Background Chronic wounds are associated with a number of deficiencies in critical wound healing processes, including growth factor signaling and neovascularization. Human-derived placental tissues are rich in regenerative cytokines and have been shown in randomized clinical trials to be effective for healing chronic wounds. In this study, PURION® Processed (MiMedx Group, Marietta, GA) dehydrated human amnion/chorion membrane tissue allografts (dHACM, EpiFix®, MiMedx) were evaluated for prope...

  6. 单层辐射人羊膜对皮损创面的促愈作用%Effect of single-layer radiation-treated human amnion on healing of skin wound surface

    Institute of Scientific and Technical Information of China (English)

    杨国华; 苗文哲; 刘彤; 赵薇; 孟庆刚; 贾继峰

    2003-01-01

    @@ INTRODUCTION Fresh human amnion used to cover burn wound surface has been reported, but its preparation and store is complicated that make it difficult for clinical application. Clinical application of single-layer radiation-treated human amnion in skin-offering and abrasion wound has achieved a good effect.

  7. Amnion s and radio-sterilized porcine skin use as potential matrices for the development of human skin substitutes; Uso de amnios y piel porcina radioesterilizados como matrices potenciales para el desarrollo de sustitutos de piel humana

    Energy Technology Data Exchange (ETDEWEB)

    Martinez P, M. E.; Reyes F, M. L.; Reboyo B, D. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Velasquillo M, M. C.; Sanchez S, R.; Brena M, A. M.; Ibarra P, J. C., E-mail: esther.martinez@inin.gob.mx [Instituto Nacional de Rehabilitacion, Calz. Mexico-Xochimilco No. 289, Col. Arenal de Guadalupe, 14389 Mexico D. F. (Mexico)

    2014-10-15

    The injuries by burns constitute a primordial problem of public health; they cause a high mortality index, severe physical and psychological disability, etc. The autologous skin transplant is the replacement therapy recommended for its treatment, but in patients that present a high percentage of burnt skin; this is not possible to carry out. Another strategy is the transplant of donated skin; however, due to the little donation that exists in our country is not very feasible to apply this treatment. A challenge of the tissues engineering is to develop biological skin substitutes, based on cells and amnion s, favoring the cutaneous regeneration and quick repair of injuries, diminishing this way the hospitalization expenses. At present skin substitutes that can equal to the same skin do not exist. On the other hand, the mesenchymal stromal cells (Msc) represent an alternative to achieve this objective; since has been demonstrated that the Msc participate in the tissue repair by means of inhibition of pro-inflammatory cytokines and differentiation to dermal fibroblasts and keratinocytes. To apply the Msc in cutaneous injuries a support material is required that to allow transplanting these cells to a lesion or burn. The radio-sterilized human amnion and the radio-sterilized porcine skin, processed by the Radio-Sterilized Tissues Bank of the Instituto Nacional de Investigaciones Nucleares (ININ), are biomaterials that are used as temporary cutaneous coverings. We suppose that these two matrices will be appropriate for the growth and maintenance in cultivation of the Msc, to generate two biological skin substitutes, in collaboration with the Biotechnology Laboratory of the Instituto Nacional de Rehabilitacion. (Author)

  8. 不同传代倍数人羊膜来源的间充质干细胞成骨成脂分化平衡的研究%Research on balance between osteogenic and adipogenic differentiation of human amnion - derived mesenchymal stem cells of different passage numbers

    Institute of Scientific and Technical Information of China (English)

    陈霞; 尹晓娟

    2011-01-01

    Objective To compare proliferative activity, osteogenic and adipogenic differentiation capacity among different passage numbers of human amniotic mesenchymal stem cells( hAMSCs ). Methods The hAMSCs were isolated from human placental basal decidua hy collagenase and trypsinase digestion methods. The superficial molecular markers of these cells were detected hy flow cytometry. After serial passage , passage 3 ,5 ,7 ,9( P3 , P5 , P7 , P9 )were singled out for the assay of proliferative activity by MTT method and the findings were delineated as growth curve. Furthermore, these cells of above four passages were respectively induced by adding osteogenic and adipogenic inducers. 3 w later, intracellular lipid deposition was verified by oil red O staining and extracellular calciumphosphate precipitates were stained with alizarin red. The positive rate of osteogenic staining and adipogenic rate were compared among different passage numbers of hAMSCs. Results hAMSCs of P9 still showed a colony - like growth property , but their proliferative activity was down regulated. Intracellular lipid droplets decreased from P5( P < 0.01 ). and extracellular calciumphosphate did from P7( P< 0.01 ). Conclusion hAMSCs can keep growth characteristics of mesenchymal stem cells during serial passage. However,multipotential differentiation capacity is varied among different passage numbers.%目的 比较不同传代倍数的人羊膜来源的间充质干细胞(hAMSCs)的增殖活性以及成骨、成脂的分化能力.方法 采用胶原酶和胰蛋白酶法分离人胎盘羊膜来源的MSCs,测定分离细胞的表面分子标志.对第3、5、7、9代hAMSCs绘制细胞生长曲线,分别加入成骨和成脂诱导剂,诱导3 w后行茜素红和油红O染色,比较不同传代倍数的hAMSCs成骨染色阳性率和成脂率.结果 hAMSCs传代至第9代时仍呈克隆样生长,但细胞增殖活力有下降;在第5代后成骨分化能力下降(P<0.01),而传代至第7代后,成

  9. Cases of limb-body wall complex: Early amnion rupture, vascular disruption, or abnormal splitting of the embryo?

    Science.gov (United States)

    Crespo, Frank; Pinar, Halit; Kostadinov, Stefan

    2012-12-01

    We report two cases of limb-body wall complex (LBWC), also known as body stalk anomaly, a rare form of body wall defect incompatible with life. The first case was identified during a level II ultrasound examination performed at 7 wk gestational age. The delivery was by breech extraction at 39 wk and 4 days. The second case was delivered by spontaneous vaginal delivery at 35 wk and 5 days. Karyotype analysis was normal in both fetuses. The phenotype of LBWC is variable, but commonly identified features include: exencephaly, limb defects, and either facial clefts or thoraco-abdominoschisis. The exact etiology remains uncertain, as the disorder has been regarded as sporadic with low recurrence. Vascular disruption during early embryogenesis, early amnion rupture, abnormal splitting of the embryo, and failure of amnion fusion have been implicated in the pathogenesis of LBWC. A role for possible gene mutation and maternal use of alcohol, tobacco, or illicit drugs has also been suggested. Detailed ultrasonography along with biochemical screening may allow for early detection.

  10. Amniotic membrane is a potential regenerative option for chronic non-healing wounds: a report of five cases receiving dehydrated human amnion/chorion membrane allograft.

    Science.gov (United States)

    Mrugala, Andrew; Sui, Audrey; Plummer, Malgorzata; Altman, Igor; Papineau, Elaine; Frandsen, Devn; Hill, Danielle; Ennis, William J

    2016-08-01

    A case series of five patients with a total of six chronic non-healing wounds (>30 day duration) were non-randomly selected to evaluate the performance, safety and handling properties of dehydrated human amnion/chorion membrane allograft, an amniotic membrane scaffolding product. The patients had lower extremity wounds that had previously failed standard of care within a university outpatient/inpatient wound healing programme. Five wounds treated with dehydrated amnion/chorion membrane allograft showed a mean 43% area reduction from baseline (51% median) at 3 weeks into treatment and completely healed with a 64-day median time to closure (SD ±27·6 days). One wound worsened at 3 weeks and was found to have a complete central vein obstruction that was treated with long-term mild compression but still eventually healed at 6 months. Removing this outlier, the four responding wounds had a 72% mean and 69% median change in area from baseline, at the 3 week point. All five patients received only one application of dehydrated human amnion/chorion membrane allograft, and there were no adverse events. The product was easy to use, administer and handle. In summary, dehydrated human amnion/chorion membrane allograft appears to be a safe, effective and easy to use therapy for chronic non-healing wounds. This study describes the details of these clinical cases and provides an overview of the current evidence on the use of amniotic tissue in clinical practice. PMID:25974156

  11. Human Amnion Epithelial Cells Induced to Express Functional Cystic Fibrosis Transmembrane Conductance Regulator

    OpenAIRE

    Murphy, Sean V.; Rebecca Lim; Philip Heraud; Marian Cholewa; Mark Le Gros; de Jonge, Martin D.; Howard, Daryl L.; David Paterson; Courtney McDonald; Anthony Atala; Graham Jenkin; Wallace, Euan M

    2012-01-01

    Cystic fibrosis, an autosomal recessive disorder caused by a mutation in a gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR), remains a leading cause of childhood respiratory morbidity and mortality. The respiratory consequences of cystic fibrosis include the generation of thick, tenacious mucus that impairs lung clearance, predisposing the individual to repeated and persistent infections, progressive lung damage and shortened lifespan. Currently there is no cure fo...

  12. Modelling the influence of amnionicity on the severity of twin-twin transfusion syndrome in monochorionic twin pregnancies

    Energy Technology Data Exchange (ETDEWEB)

    Wijngaard, Jeroen P H M van den [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Umur, Asli [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands); Ross, Michael G [Department of Obstetrics and Gynecology, Harbor University of California-Los Angeles Medical Center, Torrance, CA 90502 (United States); Gemert, Martin J C van [Laser Center and Department of Obstetrics and Gynecology, Academic Medical Center, University of Amsterdam, Amsterdam (Netherlands)

    2004-03-21

    Clinical treatment for diamniotic-monochorionic twin-twin transfusion syndrome (TTTS) may include conversion of diamniotic pregnancies to a monoamniotic-monochorionic state by disrupting the amnion septum. We sought to test the underlying hypothesis, i.e. that a monoamniotic state reduces the severity of TTTS. With use of our previously developed mathematical model of two equal fetoplacental circulatory units connected by various sizes and types of placental anastomoses, we compared the haemodynamic and amniotic fluid dynamics of monoamniotic and diamniotic twins that develop TTTS. We used three anastomotic patterns that produce severe, moderate or mild forms of TTTS, respectively, in our diamniotic-monochorionic twin model. Monoamnionicity was modelled by adding the two amniotic fluid volumes and using the volume-averaged amniotic fluid osmolality. The results were as follows: for severe TTTS, small differences develop between diamniotic and monoamniotic donor twins in fetal urine production, swallowed volume, blood volume, blood pressures, net fetofetal transfusion, and blood and amniotic fluid osmolality. However, the circulatory imbalance between the monoamniotic twins deteriorates similar to that of diamniotic twins. The pathophysiological differences tend to disappear for milder TTTS. In conclusion, our model suggests that the uncommon finding of TTTS in monoamniotic twins is not due to the presence of a single amniotic sac. Rather, clinically significant differences in anastomotic patterns and the delayed or lack of identification of manifestations in monoamniotic twins account for the reduced rate of TTTS diagnosis. Based on these results we expect the clinical disruption of the amnion septum in diamniotic-monochorionic TTTS pregnancies to have only minimal benefits. (note)

  13. Timing of Histologic Progression from Chorio-Deciduitis to Chorio-Deciduo-Amnionitis in the Setting of Preterm Labor and Preterm Premature Rupture of Membranes with Sterile Amniotic Fluid.

    Directory of Open Access Journals (Sweden)

    Chan-Wook Park

    Full Text Available Histologic chorio-deciduitis and chorio-deciduo-amnionitis (amnionitis in extra-placental membranes are known to represent the early and advanced stages of ascending intra-uterine infection. However, there are no data in humans about the time required for chorio-deciduitis to develop and for chorio-deciduitis without amnionitis to progress to chorio-deciduitis with amnionitis, and the effect of prolongation of pregnancy on the development of chorio-deciduitis and amnionitis in patients with preterm labor and intact membranes (PTL and preterm premature rupture of membranes (preterm-PROM. We examined these issues in this study.The study population consisted of 289 women who delivered preterm (133 cases with PTL, and 156 cases with preterm-PROM and who had sterile amniotic fluid (AF defined as a negative AF culture and the absence of inflammation as evidenced by a matrix metalloproteinase-8 (MMP-8 level <23 ng/ml. We examined the association between amniocentesis-to-delivery interval and inflammatory status in the extra-placental membranes (i.e., inflammation-free extra-placental membranes, choroi-deciduitis only, and chorio-deciduitis with amnionitis in patients with PTL and preterm-PROM.Amniocentesis-to-delivery interval was longer in cases of chorio-deciduitis with amnionitis than in cases of chorio-deciduitis only in both PTL (median [interquartile-range (IQR]; 645.4 [319.5] vs. 113.9 [526.9] hours; P = 0.005 and preterm-PROM (131.3 [135.4] vs. 95.2 [140.5] hours; P<0.05. Amniocentesis-to-delivery interval was an independent predictor of the development of both chorio-deciduitis and amnionitis after correction for confounding variables such as gestational age at delivery in the setting of PTL, but not preterm-PROM.These data confirm for the first time that, in cases of both PTL and preterm-PROM with sterile AF, more time is required to develop chorio-deciduitis with amnionitis than chorio-deciduitis alone in extra-placental membranes. Moreover

  14. Potential antitumor therapeutic strategies of human amniotic membrane and amniotic fluid-derived stem cells.

    Science.gov (United States)

    Kang, N-H; Hwang, K-A; Kim, S U; Kim, Y-B; Hyun, S-H; Jeung, E-B; Choi, K-C

    2012-08-01

    As stem cells are capable of self-renewal and can generate differentiated progenies for organ development, they are considered as potential source for regenerative medicine and tissue replacement after injury or disease. Along with this capacity, stem cells have the therapeutic potential for treating human diseases including cancers. According to the origins, stem cells are broadly classified into two types: embryonic stem cells (ESCs) and adult stem cells. In terms of differentiation potential, ESCs are pluripotent and adult stem cells are multipotent. Amnion, which is a membranous sac that contains the fetus and amniotic fluid and functions in protecting the developing embryo during gestation, is another stem cell source. Amnion-derived stem cells are classified as human amniotic membrane-derived epithelial stem cells, human amniotic membrane-derived mesenchymal stem cells and human amniotic fluid-derived stem cells. They are in an intermediate stage between pluripotent ESCs and lineage-restricted adult stem cells, non-tumorigenic, and contribute to low immunogenicity and anti-inflammation. Furthermore, they are easily available and do not cause any controversial issues in their recovery and applications. Not only are amnion-derived stem cells applicable in regenerative medicine, they have anticancer capacity. In non-engineered stem cells transplantation strategies, amnion-derived stem cells effectively target the tumor and suppressed the tumor growth by expressing cytotoxic cytokines. Additionally, they also have a potential as novel delivery vehicles transferring therapeutic genes to the cancer formation sites in gene-directed enzyme/prodrug combination therapy. Owing to their own advantageous properties, amnion-derived stem cells are emerging as a new candidate in anticancer therapy.

  15. Transdifferentiation of human amniotic epithelial cells into acinar cells using a double-chamber system.

    Science.gov (United States)

    Huang, Gui-Lin; Zhang, Ni-Ni; Wang, Jun-Sheng; Yao, Li; Zhao, Yu-Jie; Wang, Yu-Ying

    2012-08-01

    This study investigated the transdifferentiation of stem cells from human amnion tissue into functional acinar cells (ACs) using a co-culture system. Human amniotic epithelial cells (hAECs) were isolated from amnion tissue by mechanical mincing and enzymatic digestion. After primary culture, the phenotype of the cells was identified by flow cytometry (FCM) and immunocytochemical staining. hAECs were co-cultured with submandibular gland acinar cells of SD rats using a double-chamber system. The expression of α-amylase was determined by immunocytochemical method and fluorescent real-time quantitative reverse transcription polymerase chain reaction (RT-PCR) after induction for 1 and 2 weeks, respectively. Digestion with trypsin is an effective method for isolating hAECs from amnion tissue. These cells were positive for CD29 and CK19 and weakly positive for CD44 and α-amylase. Within 2 weeks, α-amylase in hAECs increased with induction time. The expression of α-amylase in hAECs was increased 3.38-fold after co-culturing for 1 week. This ratio increased to 6.6-fold, and these cells were positive for mucins, after co-culturing for 2 weeks. hAECs possess the potential to differentiate into ACs in vitro. They might be a stem cell resource for clinical applications of cell replacement therapy in salivary gland dysfunction diseases. PMID:22800093

  16. Effect of double-layer human amnion on wound healing in deep second-degree burns of animals%复层人羊膜覆盖治疗深Ⅱ度烫伤创面的动物实验

    Institute of Scientific and Technical Information of China (English)

    宋炬赫; 樊昌东; 李瑶

    2008-01-01

    -treated human amnion on the healing of deep second-degree burn wound.DESIGN, TIME AND SETTING: Randomized control study was performed at the Animal Experimental Center in the First Affiliated Hospital of Harbin Medical University (Harbin, Heilongjiang, China) from December 2006 to May 2007.MATERIALS: Fifty adult Wistar rats of clean grade were burned and then assigned into five groups at post-injury 4, 6, 8,10 and 12 days, with ten rats in each group. Subsequent to the chorion removal, the fresh human amniotic membrane was dried and prepared into double-layer films, which were aporate or porous. Human amnion was then radiated using γ-ray for further use.METHODS: Following dorsal skin epilatiou and the anesthesia, all the rats were immersed for 8 seconds in boiling water to induce rat models of deep second-degree burns. One side of the burn wound was applied human amnion, while the other side was applied oil gauze.MAIN OUTCOME MEASURES: Gross observation of the bum wound was carried out at post-injury 4, 6, 8, 10 and 12 days. Meanwhile, light microscope, scanning electron microscope and transmission electron microscope were employed to detect the histological changes of the burn wound, as well as bacteriological examination.RESULTS: Fifty rats were all involved in the result analysis. Sphacelism and crust were found in the burn wound treated with oil gauze, with the presence of focal ulcer at post-injury 12 days. Under light microscope, few hairs regenerated in dermis, especially hair follicle and hair root; Scanning electron microscope suggested a large amount of inflammatory exudates and leukocytes; Transmission electron microscope revealed an unclear structure of the cells. Bacteriological examination also indicated that the bacteria aecreted on the surface of burn wound. The treatment of double-layer radiation-treated human amniou healed the burn wound at post-injury 10 and 12 days, and the hairs grew with the same manner as that of normal skin. Epidermis tissues were

  17. Cat amniotic membrane multipotent cells are nontumorigenic and are safe for use in cell transplantation

    Directory of Open Access Journals (Sweden)

    Vidane AS

    2014-08-01

    Full Text Available Atanasio S Vidane,1 Aline F Souza,1 Rafael V Sampaio,1 Fabiana F Bressan,2 Naira C Pieri,1 Daniele S Martins,2 Flavio V Meirelles,2 Maria A Miglino,1 Carlos E Ambrósio2 1Department of Surgery, Faculty of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil; 2Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, São Paulo, Brazil Abstract: Amnion-derived mesenchymal stem cells (AMSCs are multipotent cells with an enhanced ability to differentiate into multiple lineages. AMSCs can be acquired through noninvasive methods, and therefore are exempt from the typical ethical issues surrounding stem cell use. The objective of this study was to isolate and characterize AMSCs from a cat amniotic membrane for future application in regenerative medicine. The cat AMSCs were harvested after mechanical and enzymatic digestion of amnion. In culture medium, the cat AMSCs adhered to a plastic culture dish and displayed a fibroblast-like morphology. Immunophenotyping assays were positive for the mesenchymal stem cell-specific markers CD73 and CD90 but not the hematopoietic markers CD34, CD45, and CD79. Under appropriate conditions, the cat AMSCs differentiated into osteogenic, chondrogenic, and adipogenic cell lineages. One advantage of cat AMSCs was nonteratogenicity, assessed 4 weeks post injection of undifferentiated AMSCs into immunodeficient mice. These findings suggest that cat amniotic membranes may be an important and useful source of mesenchymal stem cells for clinical applications, especially for cell or tissue replacement in chronic and degenerative diseases. Keywords: amnion, cats, cell differentiation, fetal membranes, mesenchymal cells

  18. [Comparison of the effects of taurine and magnesium on electrical characteristics of artificial and natural membranes. V. Study on the human amnion of the antagonism between magnesium, taurine and polluting metals].

    Science.gov (United States)

    Bara, M; Guiet-Bara, A; Durlach, J

    1985-01-01

    The effects of metal pollutants (Pb, Cd, Hg, As) were studied on strips of human amnion isolated from the placental zone put in between two Ussing chambers with Hanks' solution at 37 degrees C and pH 7.4. The total conductance Gt through the human isolated amnion was decreased on the fetal side by Pb and As; on the maternal side by Cd, Hg and As. When Gt was decreased by metal pollutants, Mg or taurine (TA) were added in the external medium to induce an antagonism between Mg or TA and metal pollutants. The addition of Mg increased significantly the Gt reduced by Pb, Cd and Hg, but had no effect on the Gt reduced by As. The addition of taurine increased significantly the Gt reduced by Cd and Hg, but had no effect on the Gt reduced by Pb and As. Dixon's kinetics (Gt as a function of the Mg or TA concentration when the metal pollutant concentration increased) indicate that there is a competitive inhibition between Mg-Pb and Mg-Cd (the inhibition constant Ki is lower with Pb (= 2.5) than with Cd (= 11.4) and suggests a greater antagonism between Mg-Pb than between Mg-Cd). Moreover, there appears to be a noncompetitive inhibition between Mg-Hg, TA-Cd and TA-Hg. These results indicate that Mg and TA, on the fetal side, exert an action on the same sites and that, on the maternal side, their action takes place on the same sites and also on different ones. Also, TA can be considered as a partial magnesium agonist, at least in the human amnion.

  19. A prospective, randomised comparative study of weekly versus biweekly application of dehydrated human amnion/chorion membrane allograft in the management of diabetic foot ulcers

    Science.gov (United States)

    Zelen, Charles M; Serena, Thomas E; Snyder, Robert J

    2014-01-01

    The aim of this study is to determine if weekly application of dehydrated human amnion/chorion membrane allograft reduce time to heal more effectively than biweekly application for treatment of diabetic foot ulcers. This was an institutional review board-approved, registered, prospective, randomised, comparative, non-blinded, single-centre clinical trial. Patients with non-infected ulcers of ≥ 4 weeks duration were included for the study. They were randomised to receive weekly or biweekly application of allograft in addition to a non-adherent, moist dressing with compressive wrapping. All wounds were offloaded. The primary study outcome was mean time to healing. Overall, during the 12-week study period, 92·5% (37/40) ulcers completely healed. Mean time to complete healing was 4·1 ± 2·9 versus 2·4 ± 1·8 weeks (P = 0·039) in the biweekly versus weekly groups, respectively. Complete healing occurred in 50% versus 90% by 4 weeks in the biweekly and weekly groups, respectively (P = 0·014). Number of grafts applied to healed wounds was similar at 2·4 ± 1·5 and 2·3 ± 1·8 for biweekly versus weekly groups, respectively (P = 0·841). These results validate previous studies showing that the allograft is an effective treatment for diabetic ulcers and show that wounds treated with weekly application heal more rapidly than with biweekly application. More rapid healing may decrease clinical operational costs and prevent long-term medical complications. PMID:24618401

  20. Human amniotic epithelial cells express specific markers of nerve cells and migrate along the nerve fibers in the corpus callosum

    Institute of Scientific and Technical Information of China (English)

    Zhiyuan Wu; Guozhen Hui; Yi Lu; Tianjin Liu; Qin Huang; Lihe Guo

    2012-01-01

    Human amniotic epithelial cells were isolated from a piece of fresh amnion. Using immunocytochemical methods, we investigated the expression of neuronal phenotypes (microtubule-associated protein-2, glial fibrillary acidic protein and nestin) in human amniotic epithelial cells. The conditioned medium of human amniotic epithelial cells promoted the growth and proliferation of rat glial cells cultured in vitro, and this effect was dose-dependent. Human amniotic epithelial cells were further transplanted into the corpus striatum of healthy adult rats and the grafted cells could integrate with the host and migrate 1-2 mm along the nerve fibers in corpus callosum. Our experimental findings indicate that human amniotic epithelial cells may be a new kind of seed cells for use in neurograft.

  1. Progesterone, Inflammatory Cytokine (TNF-α), and Oxidative Stress (H2O2) Regulate Progesterone Receptor Membrane Component 1 Expression in Fetal Membrane Cells.

    Science.gov (United States)

    Meng, Yan; Murtha, Amy P; Feng, Liping

    2016-09-01

    Progesterone receptor membrane component 1 (PGRMC1) is an important novel mediator of progesterone (P4) function in fetal membrane cells. We demonstrated previously that PGRMC1 is differentially expressed in fetal membranes among pregnancy subjects and diminished in preterm premature rupture of membrane subjects. In the current study, we aim to elucidate whether PGRMC1 expression is regulated by P4, tumor necrosis factor α (TNF-α), and H2O2 in fetal membrane cells. Primary cultured membrane cells were serum starved for 24 hours followed by treatments of P4, 17 hydroxyprogesterone caproate, and medroxyprogesterone 17 acetate (MPA) at 10(-7) mol/L with ethanol as vehicle control; TNF-α at 10, 20, and 50 ng/mL with phosphate-buffered saline (PBS) as control; and H2O2 at 10 and 100 μmol/L with culture media as control for 24, 48, and 72 hours. The messenger RNA (mRNA) and protein expression of PGRMC1 was quantified using polymerase chain reaction and Western blotting, respectively. We found that PGRMC1 protein expression was regulated by MPA, TNF-α, and H2O2 in a dose-dependent manner. This regulation is also specific to the type of cell (amnion, chorion, or decidua). The upregulation of PGRMC1 by MPA might be mediated through glucocorticoid receptor (GR) demonstrated using amnion and chorion cells model with GR knockdown by specific small interfering RNA transfection. The mRNA expression of PGRMC1 was decreased by H2O2 (100 μmol/L) treatment in amnion cells, which might ultimately result in downregulation of PGRMC1 protein as our data demonstrated. None of other treatments changed PGRMC1 mRNA level in these cells. We conclude that these stimuli act as regulatory factors of PGRMC1 in a cell-specific manner. PMID:26919974

  2. The potential of mesenchymal stem cells derived from amniotic membrane and amniotic fluid for neuronal regenerative therapy.

    Science.gov (United States)

    Kim, Eun Young; Lee, Kyung-Bon; Kim, Min Kyu

    2014-03-01

    The mesenchymal stem cells (MSCs), which are derived from the mesoderm, are considered as a readily available source for tissue engineering. They have multipotent differentiation capacity and can be differentiated into various cell types. Many studies have demonstrated that the MSCs identified from amniotic membrane (AM-MSCs) and amniotic fluid (AF-MSCs) are shows advantages for many reasons, including the possibility of noninvasive isolation, multipotency, self-renewal, low immunogenicity, anti-inflammatory and nontumorigenicity properties, and minimal ethical problem. The AF-MSCs and AM-MSCs may be appropriate sources of mesenchymal stem cells for regenerative medicine, as an alternative to embryonic stem cells (ESCs). Recently, regenerative treatments such as tissue engineering and cell transplantation have shown potential in clinical applications for degenerative diseases. Therefore, amnion and MSCs derived from amnion can be applied to cell therapy in neuro-degeneration diseases. In this review, we will describe the potential of AM-MSCs and AF-MSCs, with particular focus on cures for neuronal degenerative diseases.

  3. Tissue-specific Differentiation Potency of Mesenchymal Stromal Cells from Perinatal Tissues.

    Science.gov (United States)

    Kwon, Ahlm; Kim, Yonggoo; Kim, Myungshin; Kim, Jiyeon; Choi, Hayoung; Jekarl, Dong Wook; Lee, Seungok; Kim, Jung Min; Shin, Jong-Chul; Park, In Yang

    2016-04-05

    Human perinatal tissue is an abundant source of mesenchymal stromal cells(MSCs) and lacks the ethical concerns. Perinatal MSCs can be obtained from various tissues as like amnion, chorion, and umbilical cord. Still, little is known of the distinct nature of each MSC type. In this study, we successfully isolated and cultured MSCs from amnion(AMSCs), chorion(CMSCs), and umbilical cord(UC-MSCs). Proliferation potential was different among them, that AMSCs revealed the lowest proliferation rate due to increased Annexin V and senescence-associated β-galactosidase positive cells. We demonstrated distinct characteristic gene expression according to the source of the original tissue using microarray. In particular, genes associated with apoptosis and senescence including CDKN2A were up-regulated in AMSCs. In CMSCs, genes associated with heart morphogenesis and blood circulation including HTR2B were up-regulated. Genes associated with neurological system processes including NPY were up-regulated in UC-MSCs. Quantitative RT-PCR confirmed the gene expression data. And in vitro differentiation of MSCs demonstrated that CMSCs and UC-MSCs had a more pronounced ability to differentiate into cardiomyocyte and neural cells, respectively. This study firstly demonstrated the innate tissue-specific differentiation potency of perinatal MSCs which can be helpful in choosing more adequate cell sources for better outcome in a specific disease.

  4. Therapeutic outcomes of transplantation of amniotic fluid-derived stem cells in experimental ischemic stroke

    Directory of Open Access Journals (Sweden)

    Naoki eTajiri

    2014-08-01

    Full Text Available Accumulating preclinical evidence suggests the use of amnion as a source of stem cells for investigations of basic science concepts related to developmental cell biology, but also for stem cells’ therapeutic applications in treating human disorders. We previously reported isolation of viable rat amniotic fluid-derived stem (AFS cells. Subsequently, we recently reported the therapeutic benefits of intravenous transplantation of AFS cells in a rodent model of ischemic stroke. Parallel lines of investiagtions have provided safety and efficacy of stem cell therapy for treating stroke and other neurological disorders. This review article highlights characterization of AFS cells’ phenotype and their transplant-mediated functional effects, the need for investigations of mechanisms underlying AFS cells’ therapeutic benefits and discusses lab-to-clinic translational gating items in an effort to optimize the clinical application of cell transplantation for stroke.

  5. Experimental study on the effect of human amnion on MMP-9 expression during healing process of rat skin incised wound%人羊膜对大鼠皮肤切创愈合中MMP-9表达影响的实验研究

    Institute of Scientific and Technical Information of China (English)

    罗秋燕; 边文玲; 申素芳

    2012-01-01

    目的:研究人羊膜对大鼠皮肤切创愈合过程中感染率的影响及基质金属蛋白酶-9(Matrix metalloproteinase-9,MMP-9)表达影响的研究及意义,探讨其促进皮肤愈合的机制,为其在临床的应用提供实验依据.方法:建立大鼠皮肤切创模型,观察切口愈合时间、感染率;在各时相点处死取材,应用免疫组织化学技术,通过计算机图像分析系统检测人胎羊膜对不同损伤时间大鼠皮肤组织中MMP -9的表达.结果:新鲜羊膜组感染率(6.7%)与对照组(33.3%)比较,创面感染率明显低于对照组,差异有统计学意义(P<0.05);在伤后12 h、1天、2天、3天,新鲜羊膜组MMP -9的表达高于对照组,差异有统计学意义(P<0.05),5天、7天两组的表达差异无统计学意义(P>0.05).结论:羊膜贴附创口能减少创口的感染率;在大鼠皮肤切创愈合的早期阶段,可通过促进创缘周围MMP -9的表达,加速清创,促进创口的愈合.%Objective: To research the effect of human amnion on infection rale and matrix metalloproteinase - 9 (MMP-9) expression during healing process of rat skin incised wound and its significance, explore the mechanism of its promoting effect on healing of rat skin, provide an experimental basis for the clinical application. Methods: The models of rat skin incised wound were established, the wound healing time and infection rate were observed; the rats were killed at different time points; immunohistochemical method was used to detect the effect of human amnion on MMP-9 expression in skin tissue at different time points by computer image analysis system. Results: The wound infection rate in fresh amnion group was 6.7% , which was significantly lower than that in control group (33. 3% ) (P 0.05 ) . Conclusion: Amnion adhered to wound can reduce the infection rate of incised wound; at early stage of rat skin incised wound healing, amnion can promote wound debridement and healing by promoting the expression of

  6. Mesenchymal stromal cells from the human placenta promote neovascularization in a mouse model in vivo.

    Science.gov (United States)

    Kinzer, M; Hingerl, K; König, J; Reinisch, A; Strunk, D; Huppertz, B; Lang, I

    2014-07-01

    Cell transplantation is a promising strategy in regenerative medicine for revascularization of ischemic tissues. Based on our observation that placental mesenchymal stromal cells (PMSC) enhance endothelial cell viability in vitro via secretion of angiogenic factors, we asked whether PMSC support vascular growth in vivo. PMSC were isolated from amnion and placental endothelial cells (PLEC) from chorion and either separately or co-transplanted subcutaneously into immune-deficient mice. Co-transplantation resulted in a higher number of perfused human vessels (CD31+/vimentin+) containing mouse glycophorin A+ erythrocytes. Results indicate positive effects of PMSC on neovascularization in vivo, making them attractive candidates to create autologous PMSC/PLEC pairs for research and transplantation.

  7. 羊膜卷填塞治疗角膜穿孔羊膜的演变及对角膜内皮细胞的影响%The evolution of amnion and influnce on corneal endothelium in amniotic roll plugging for corneal perforation

    Institute of Scientific and Technical Information of China (English)

    范军华; 何伟杰; 叶瑞珍; 李学喜

    2014-01-01

    Objective To observe the evolution of amnion and influnce on corneal endothelium in amniotic roll plugging combined with C3F8 tamponade in anterior chamber to treat corneal perforation.Methods 56 eyes of 56 patients with corneal perforation accepted the operation of amniotic roll plugging combined with C3F8 tamponade in anterior chamber and the concentration of C3F8 gas was 20%.Anterior chamber depth,aqueous leakage,bubbles maintenance time,corneal endothelial cell density and morphology and the fusion of amniotic roll and corneal tissue were observed.Results Corneal perforation of 56 eyes were all repaired without amniotic roll falling off.The fusion of amniotic roll and corneal tissue was observed at 2 months after operation,and the amniotic roll and corneal tissue fused well and no gap was examined.The C3F8 gas stayed in the anterior chamber for 5 ~ 16 days,average of (8.2 ± 4.8) days.There was no significant difference in corneal endothelial cell density between preoperative and postoperative 1 month or 2 month.The percentage of hexagonal cells decreased at postoperative 1 month compared with preoperative (t =2.13,P > 0.05),and there was no significant difference between postoperative 1 month and 2 months (t =1.65,P > 0.05).Conclusion Amniotic roll plugging combined with C3 F8 gas tamponade in anterior chamber can effectively repair corneal perforation,and the amniotic roll and cornea can fuse well after operation.C3F8 gas can stay in the anterior chamber long enough to maintain the anterior chamber depth and prevent leakage of aqueous humor.Little influnce on the corneal endothelium was observed.%目的 观察羊膜卷填塞联合C3F8气体填充治疗角膜穿孔术后羊膜的演变及其对角膜内皮细胞的影响.方法 因各种原因所致角膜穿孔而施行羊膜卷填塞联合前房C3F8气体填充术共56例(56眼).术中以20%C3F8气体填充前房.术后观察前房深度、房水渗漏情况、气泡维持时间、角膜内皮细

  8. The amniotic membrane as a source of stem cells.

    Science.gov (United States)

    Insausti, Carmen L; Blanquer, Miguel; Bleda, Patricia; Iniesta, Paqui; Majado, María J; Castellanos, Gregorio; Moraleda, José M

    2010-01-01

    Cellular therapy has emerged as a new potential tool for curing a wide range of degenerative diseases and tissue necrosis. Embryonic stem cells possess potential for differentiation into a wide range of cell lineages, but the ethical issues associated with establishment of this human cell line have to be resolved prior to any use. The bone marrow (BM) is the usual source of adult stem cells for hematopoietic stem cell transplants and cellular therapy, but the BM harvest is a surgical procedure that requires general anesthesia or sedation, and there seems to be a reduction of the proliferative potential and differentiation capacity of the marrow mesenchymal stem cells in older donors. For these reasons there is an increasing interest in other sources of stem cells from adult and fetal tissues. The amniotic membrane (AM) or amnion is a tissue of particular interest because its cells possess characteristics of stem cells with multipotent differentiation ability, and because of low immunogenicity and easy procurement from the placenta, which is a discarded tissue after parturition, thus avoiding the current controversies associated with the use of human embryonic stem cells. Therefore, amniotic membrane has been proposed as a good candidate to be used in cellular therapy and regenerative medicine. PMID:19924645

  9. EFFECT OF OKADAIC ACID ON APOPTOSIS IN HUMAN AMNION CELLS%大田软海绵酸对人胚胎羊膜细胞FL凋亡的影响

    Institute of Scientific and Technical Information of China (English)

    邢鸣鸾; 陈加平; 王晓峰; 徐进; 徐立红

    2007-01-01

    大田软海绵酸(Okadaic acid,OA)是一种C38的长链脂肪酸,属聚醚类海洋毒素,是腹泻性贝毒(Diarrhetic shellfish poisoning,DSP)的主要成分,化学结构见下图。最初从大田软海绵(Halichondria Okadai)和隐瓜海绵(H.melanodocia)中分离得到,后发现实际上是由共生于上述两种海绵的利马原甲藻(Prorocentrum lima)所产生。

  10. Mesenchymal stem cells from rat olfactory bulbs can differentiate into cells with cardiomyocyte characteristics.

    Science.gov (United States)

    Huang, Yuahn-Sieh; Li, I-Hsun; Chueh, Sheau-Huei; Hueng, Dueng-Yuan; Tai, Ming-Cheng; Liang, Chang-Min; Lien, Shiu-Bii; Sytwu, Huey-Kang; Ma, Kuo-Hsing

    2015-12-01

    Mesenchymal stromal/stem cells (MSCs) are widely distributed in different tissues such as bone marrow, adipose tissues, peripheral blood, umbilical cord and amnionic fluid. Recently, MSC-like cells were also found to exist in rat olfactory bulb and are capable of inducing differentiation into mesenchymal lineages - osteocytes, chondrocytes and adipocytes. However, whether these cells can differentiate into myocardial cells is not known. In this study, we examined whether olfactory bulb-derived MSCs could differentiate into myocardial cells in vitro. Fibroblast-like cells isolated from the olfactory bulb of neonatal rats were grown under four conditions: no treatment; in the presence of growth factors (neuregulin-1, bFGF and forskolin); co-cultured with cardiomyocytes; and co-cultured with cardiomyocytes plus neuregulin-1, bFGF and forskolin. Cell differentiation into myocardial cells was monitored by RT-PCR, light microscopy immunofluorescence, western blot analysis and contractile response to pharmacological treatments. The isolated olfactory bulb-derived fibroblast-like cells expressed CD29, CD44, CD90, CD105, CD166 but not CD34 and CD45, consistent with the characteristics of MSCs. Long cylindical cells that spontaneously contracted were only observed following 7 days of co-culture of MSCs with rat cardiomyocytes plus neuregulin-1, bFGF and forskolin. RT-PCR and western blot analysis indicated that the cylindrical cells expressed myocardial markers, such as Nkx2.5, GATA4, sarcomeric α-actinin, cardiac troponin I, cardiac myosin heavy chain, atrial natriuretic peptide and connexin 43. They also contained sarcomeres and gap junction and were sensitive to pharmacological treatments (adrenal and cholinergic agonists and antagonists). These findings indicate that rat olfactory bulb-derived fibroblast-like cells with MSC characteristics can differentiate into myocardial-like cells.

  11. Multilineage Potential Research of Bovine Amniotic Fluid Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    Yuhua Gao

    2014-02-01

    Full Text Available The use of amnion and amniotic fluid (AF are abundant sources of mesenchymal stem cells (MSCs that can be harvested at low cost and do not pose ethical conflicts. In human and veterinary research, stem cells derived from these tissues are promising candidates for disease treatment, specifically for their plasticity, their reduced immunogenicity, and high anti-inflammatory potential. This work aimed to obtain and characterize bovine amniotic fluid mesenchymal stem cells (AFMSC. The bovine AF from the amniotic cavity of pregnant gilts in the early stages of gestation (3- and 4-m-old bovine embryos was collected. AFMSCs exhibit a fibroblastic-like morphology only starting from the fourth passage, being heterogeneous during the primary culture. Immunofluorescence results showed that AFMSCs were positive for β-integrin, CD44, CD73 and CD166, but negative for CD34, CD45. Meanwhile, AFMSCs expressed ES cell markers, such as Oct4, and when appropriately induced, are capable of differentiating into ectodermal and mesodermal lineages. This study reinforces the emerging importance of these cells as ideal tools in veterinary medicine; future studies aimed at a deeper evaluation of their immunological properties will allow a better understanding of their role in cellular therapy.

  12. DNA methylation dynamics in human induced pluripotent stem cells over time.

    Directory of Open Access Journals (Sweden)

    Koichiro Nishino

    2011-05-01

    Full Text Available Epigenetic reprogramming is a critical event in the generation of induced pluripotent stem cells (iPSCs. Here, we determined the DNA methylation profiles of 22 human iPSC lines derived from five different cell types (human endometrium, placental artery endothelium, amnion, fetal lung fibroblast, and menstrual blood cell and five human embryonic stem cell (ESC lines, and we followed the aberrant methylation sites in iPSCs for up to 42 weeks. The iPSCs exhibited distinct epigenetic differences from ESCs, which were caused by aberrant methylation at early passages. Multiple appearances and then disappearances of random aberrant methylation were detected throughout iPSC reprogramming. Continuous passaging of the iPSCs diminished the differences between iPSCs and ESCs, implying that iPSCs lose the characteristics inherited from the parent cells and adapt to very closely resemble ESCs over time. Human iPSCs were gradually reprogrammed through the "convergence" of aberrant hyper-methylation events that continuously appeared in a de novo manner. This iPS reprogramming consisted of stochastic de novo methylation and selection/fixation of methylation in an environment suitable for ESCs. Taken together, random methylation and convergence are driving forces for long-term reprogramming of iPSCs to ESCs.

  13. Upregulated expression of Ezrin and invasive phenotype in malignantly transformed esophageal epithelial cells

    Institute of Scientific and Technical Information of China (English)

    Zhong-Ying Shen; Li-Yan Xu; Ming-Hua Chen; En-Min Li; Jin-Tao Li; Xian-Ying Wu; Yi Zeng

    2003-01-01

    AIM: To investigate the correlation between ezrin expression and invasive phenotype formation in malignantly transformed esophageal epithelial cells. METHODS: The experimental cell line employed in the present study was originated form the progressive induction of a human embryonic esophageal epithelial cell line (SHEE)by the E6E7 genes of human papillomavirus (HPV) type 18.The cells at the 35th passage after induction called SHEEIMM were in a state of immortalized phase and used as the control,while that of the 85th passage denominated as SHEEMT represented the status of cells that were malignantly transformed. The expression changes of ezrin and its mRNA in both cell passages were respectively analyzed by RT-PCR and Western blot. Invasive phenotype was assessed in vivo by inoculating these cells into the severe combined immunodeficient (SCID) mice via subcutaneous and intraperitoneal injection, and in vitro by inoculating them on the surface of the amnion membranes, which then was determined by light microscopy and scanning electron microscopy. RESULTS: Upregulated expression of ezrin protein and its mRNA was observed in SHEEMT compared with that in SHEEIMM cells. The SHEEMT cells inoculated in SCID mice were observed forming tumor masses in both visceral organs and soft tissues in a period of 40 days with a special propensity to invading mesentery and pancreas, but did not exhibit hepatic metastases. Pathologically, these tumor cells harboring larger nucleus, nucleolus and less cytoplasm could infiltrate and destroy adjacent tissues. In the in vitro study,the inoculated SHEEMT cells could grow in cluster on the amniotic epithelial surface and intrude into the amniotic stroma. In contrast, unrestricted growth and invasiveness were not found in SHEEIMM cells in both in vivo and in vitroexperiment. CONCLUSION: The upregulated ezrin expression is one of the important factors that are possibly associated with the invasive phenotype formation in malignantly

  14. Isolation and biological characteristics of three kinds of human placenta-derived mesenchymal stem cells%三种胎盘间充质干细胞的分离培养及生物学特性对比研究

    Institute of Scientific and Technical Information of China (English)

    刘丽; 黎渊明; 刘琴; 张亚光; 毛圆圆; 宋云庆

    2012-01-01

    目的 分离培养人胎盘羊膜、绒毛膜和蜕膜三种间充质干细胞(mesenchymal stem cells,MSCs),进行生物学特性对比研究.方法 酶消化法分离胎盘羊膜、绒毛膜和蜕膜内干细胞,体外培养传代,MTT法测定细胞生长曲线,流式细胞术检测细胞表面标志,茜素红和油红O检测成骨和成脂能力.结果 表面标记鉴定分离的胎盘细胞为间充质干细胞,细胞具增殖和分化能力.三种细胞在传代过程中细胞形态、表面标志表达、分化能力维持稳定,但增殖能力存在差异.结论 成功分离获得三种胎盘MSCs,可以作为临床前研究用MSCs来源.%Objective To isolate mesenchymal stem cells from human amnions, chorions and decidua basalis, and compare their biological characteristics. Methods Stem cells were obtained by enzymatic digestion method from human amnions, chorions and decidua basalis and cultured in vitro. Cell growth curves were made by MIT method. Cell surface markers were assayed by flow cytometry. Osteogenic and adipogenic differentiation capacity was determined by alizarin red and alizarin red staining. Results Three kinds of placenta-derived mesenchymal stem cells were confirmed by cell surface markers assay. And these cells possess proliferation and differentiation ability. Cell morphology, surface markers and differentiation ability maintained stability during passage. However difference was detected in growth ability. Conclusion Three kinds of human placenta-derived stem cells were isolated and cultured successfully, and they could be used as seed cells in later preclinical study.

  15. Comparative Characterization of Cells from the Various Compartments of the Human Umbilical Cord Shows that the Wharton's Jelly Compartment Provides the Best Source of Clinically Utilizable Mesenchymal Stem Cells.

    Directory of Open Access Journals (Sweden)

    Arjunan Subramanian

    Full Text Available The human umbilical cord (UC is an attractive source of mesenchymal stem cells (MSCs with unique advantages over other MSC sources. They have been isolated from different compartments of the UC but there has been no rigorous comparison to identify the compartment with the best clinical utility. We compared the histology, fresh and cultured cell numbers, morphology, proliferation, viability, stemness characteristics and differentiation potential of cells from the amnion (AM, subamnion (SA, perivascular (PV, Wharton's jelly (WJ and mixed cord (MC of five UCs. The WJ occupied the largest area in the UC from which 4.61 ± 0.57 x 106 /cm fresh cells could be isolated without culture compared to AM, SA, PV and MC that required culture. The WJ and PV had significantly lesser CD40+ non-stem cell contaminants (26-27% compared to SA, AM and MC (51-70%. Cells from all compartments were proliferative, expressed the typical MSC-CD, HLA, and ESC markers, telomerase, had normal karyotypes and differentiated into adipocyte, chondrocyte and osteocyte lineages. The cells from WJ showed significantly greater CD24+ and CD108+ numbers and fluorescence intensities that discriminate between MSCs and non-stem cell mesenchymal cells, were negative for the fibroblast-specific and activating-proteins (FSP, FAP and showed greater osteogenic and chondrogenic differentiation potential compared to AM, SA, PV and MC. Cells from the WJ offer the best clinical utility as (i they have less non-stem cell contaminants (ii can be generated in large numbers with minimal culture avoiding changes in phenotype, (iii their derivation is quick and easy to standardize, (iv they are rich in stemness characteristics and (v have high differentiation potential. Our results show that when isolating MSCs from the UC, the WJ should be the preferred compartment, and a standardized method of derivation must be used so as to make meaningful comparisons of data between research groups.

  16. 成体干细胞向血管内皮细胞定向分化的研究现状%Oriented differentiation of adult stem cells into vascular endothelial cells

    Institute of Scientific and Technical Information of China (English)

    宋秀军; 江其生

    2009-01-01

    Adult stem cells identified in tissue organs possess obviously plasticity. They can differentiate into the cells in other systems and germ layers, which are known to support the continuous repair and regeneration of tissues. In the vascular tissue engineering, the research was more and more widespread and deep on adult stem cells as seed cells~ Research indicated that there are many kinds of adult stem cells which can differentiate into vascular endothelial cells, such as bone marrow mesenchymal stem cells, hematopoietic stem cells, human adipose derived stem cells, and amnion derived stem calls. Thus, this study reviewed the current situation of adult stem cells as seed cells in vascular tissue engineering.%成体干细胞存在于已分化的组织器官中,具有明显的可塑性,能跨系统、跨胚层分化,在组织工程和损伤修复领域具有重要的应用价值.在血管组织工程研究领域中,成体干细胞作为种子细胞得到越来越广泛而深入的研究.目前研究表明,具有向血管内皮细胞分化的成体干细胞主要有骨髓间充质干细胞、造血干细胞、脂肪来源的干细胞以及羊膜来源的干细胞等基于此,就成体干细胞作为种子细胞在血管组织工程领域研究现状进行综述.

  17. Clinical observatiom of corneal limbal stem cell auto-grafting,the transplantation of anmion and the pure removal of pterygium to treat the recurrent pterygium%角膜缘干细胞移植与羊膜移植及单纯胬肉切除治疗复发性翼状胬肉的疗效比较

    Institute of Scientific and Technical Information of China (English)

    唐茂聪; 唐铮; 沈亚玲

    2008-01-01

    Objective The effect analyses by comparing and observing corneal limbal stem cell auto-grafting,the transplantation of flesh amnlon and the pure removal of pterygium to treat the recurrent pterygium.Method 166 cases of recurrent Pterygium( 176 eyes)is divides into 3 groups(named A,B,and C) randomly.Group A (with 67 cases, 72 eyes)is operated by removing the recurrent pterygium and corneal limbal stem cell auto-grafting.Group B (with 58 cases,59 eyes)is operated by removing the recurrent pterygium and the transplantation of flesh amnion.Group C (with 43 eases,45 eyes)is only operated by removing the pterygium.After operation,visits lasting 6-60 months are followed and comparations about the patients' symptoms,the wound matches and the pterygium relapses among the 3 groups are carried out.Result In group A,28 eyes relapsed from the whole 72 eyes,and the rate of relapsing is 39%.In group B,28 eyes relapsed from the whole 59 eyes,and the rate of relapsing is 47.5%.In group C,39 eyes relapsed from the whole 45 eyes,with the rate of relapsing 86.6%.Conclusion Compared with the effect of the pure removal pterygium to treat recurrent pterygium, there exist lower rates of relapsing in corneal limbai stem cell autografting and the transplantation of fresh amnion.Corneal limbal stem cell auto-grafting is more effective than the transplantation of flesh amnion in lowering the rate of relapsing recurrent pterygium.In addition, corneal iimbal stem cells are easily to be found and economical,and it is the effective option in treating recurrent pterygium.%目的 比较自体角膜缘干细胞移植与新鲜羊膜移植及单纯胬肉切除治疗复发性翼状胬肉的疗效.方法 对复发性翼状胬肉166例(176只眼),随机分为A、B、C 3组,A组67例,72只眼,行复发性翼状胬肉切除联合自体角膜缘干细胞移植术.B组58例,59只眼,行复发性翼状胬肉切除联合新鲜羊膜移植术.C组43例,45只眼,行单纯胬肉切除.手术后随访6~60

  18. Liposome-mediated IL-28 and IL-29 expression in A549 cells and antiviral effect of IL-28 and IL-29 on WISH cells

    Institute of Scientific and Technical Information of China (English)

    Ming-cai LI; Hao-yang WANG; Hai-yan WANG; Tao LI; Shao-heng HE

    2006-01-01

    Aim:To construct the recombinant vectors carrying interleukin (IL) -28A,IL-28B and IL-29 cDNAs and express them in human A549 cells,and analyze their antiviral activity in vesicular stomatitis virus (VSV)-infected human immortalized amnion epithelial cell line (WISH cells).Methods:Total cell RNA was extracted from human peripheral blood mononuclear cells (PBMC) activated with poly I:C.The cDNAs encoding human IL-28A.IL-28B.and IL-29 were amplified by reversetranscription polymerase chain reaction (RT-PCR) and inserted into pcDNA3.1/V5-His-TOPO vectors.These recombinant vectors were transfected into human A549 cells by a liposome-mediated gene transfer method.Semiquantitative RT-PCR and Westem blotting were used to detect the mRNA and protein expression of IL-28A,IL-28B,and IL-29.The antiviral activity of IL-28A,IL.28B,and IL-29 was determined by a cytopathic eflfect reduction assay on WISH cells using VSV as a challenge virus.Results:The DNA sequences of the inserts were identical to the published sequences encoding IL-28A,IL-28B,and IL-29 in GenBank.It was transfected cells.Expression of all 3 interleukins in A549 cells was confirmed by Wlestem blot analysis.IL-28 and IL-29 expressed by A549 cells.1ike interferon (IFN)α-2b,were able to protect WISH cells against VSV infection.Conclusion:IL-28 and IL-29 cDNAs were successfully cloned and expressed in eukaryotic cells via transfection with pcDNA3.1/V5-His-TOPO-IL-28/IL-29.Transfection with this vector produced a specific antiviral activity similar to that of IFN-α.which will provide a new tool for the functional study of these cytokines in humans.

  19. 人羊膜间充质干细胞静脉移植治疗阿尔茨海默病APP+转基因鼠的有效性及安全性评估%Efficacy and safety assessment of intravenous transplantation of human amnion membrane mesenchymal stem cells in treatment of APP+ transgenic mice with Alzheimer's disease

    Institute of Scientific and Technical Information of China (English)

    郭亚男; 李远; 关方霞; 李国栋; 李祥生; 杨波; 杜英; 胡祥; 胡炜; 焦红亮

    2009-01-01

    背景:目前阿尔茨海默病的病因不明,课题组前期实验发现人羊膜间充质干细胞静脉移植可促进阿尔茨海驮病APP+转基因鼠的学习、记忆能力改善.目的:进一步评估人羊膜间充质干细胞静脉移植治疗阿尔茨海默病APP+转基因鼠的有效性和安全性.设计、时间及地点:细胞学体内实验与动物对照观察,于2008-05/12在郑州大学生物工程系、郑州大学基础医学院及河南省中医药研究院完成.材料:清洁级C57BL/6系APP+转基因胎鼠10只,合笼繁育后得到子代小鼠200只,按其繁殖情况和PCR榆测结果,取29只11月龄小鼠,分为APP+对照组10只、APP+细胞移植组10只、APP+正常组9只.羊膜标本由郑州大学第一附属医院产科提供.方法:体外分离培养人羊膜间充质干细胞,传至第3代后调整浓度为1×109 L-1的单细胞悬液.APP+细胞移植组每只小鼠尾静脉注射人羊膜间充质干细胞悬液O.5 mL,APP+对照组注射等量生理盐水,APP+正常组不作任何处理.主要观察指标:采用Morris水迷宫测定移植前后小鼠学习和记忆功能.移植当天开始称小鼠体质量,持续3周.移植后解剖小鼠,收集全血并分离血清,进行12项肿瘤标记物检测及心、肝、肾功能的血液生化指标检测,对人羊膜间充质干细胞移植的安全性作综合评价.结果:移植后15d各组逃避潜伏期比较,APP-正常组<APP+细胞移植组<APP+对照组,APP+细胞移植组小鼠逃避潜伏期明显短于APP+对照组(P<0.05);与移植前比较,移植后15d各组小鼠穿越平台象限的次数均有所增加,且APP+细胞移植组小鼠在平台象限停留时间明显延长.移植后3周内,3组小鼠体质量增长趋势差异无显著性意义(P>0.05),12项肿瘤标记物,9项血清肝肾功能生化指标及10项血液学指标的表达均无明显差异(P>0.05). 结论:人羊膜间充质干细胞经尾静脉移植后,可明显改善阿尔茨海默病小鼠的学习、记忆能力,未见致死致瘤现象发生,心、肝、肾功能未受影响,安全可行.

  20. Transplantation of human amniotic epithelial cells improves hindlimb function in rats with spinal cord injury

    Institute of Scientific and Technical Information of China (English)

    WU Zhi-yuan; HUI Guo-zhen; LU Yi; WU Xin; GUO Li-he

    2006-01-01

    Background Human amniotic epithelial cells (HAECs), which have several characteristics similar to stem cells,therefore could possibly be used in cell therapy without creating legal or ethical problems. In this study, we transplanted HEACs into the injured spinal cord of rats to investigate if the cells can improve the rats' hindlimb motor function.Methods HAECs were obtained from a piece of fresh amnion, labeled with Hoechst33342, and transplanted into the site of complete midthoracic spinal transections in adult rats. The rats (n=21) were randomly divided into three groups: Sham-operation group (n=7), cells-graft group (n=7), and PBS group (n=7). One rat of each group was killed for histological analysis at the second week after the transplantation. The other six rats of each group were killed for histological analysis after an 8-week behavioral testing. Hindlimb motor function was assessed by using the open-field BBB scoring system. Survival rate of the graft cells was observed at second and eighth weeks after the transplantation. We also detected the myelin sheath fibers around the lesions and the size of the axotomized red nucleus. A one-way ANOVA was used to compare the means among the groups. The significance level was set at P<0.05.Results The graft HAECs survived for a long time (8 weeks) and integrated into the host spinal cord without immune rejection. Compared with the control group, HAECs can promote the regeneration and sprouting of the axons, improve the hindlimb motor function of the rats (BBB score: cells-graft group 9.0± 0.89 vs PBS group 3.7± 1.03, P<0.01), and inhibit the atrophy of axotomized red nucleus [cells-graft group (526.47 ± 148.42) μm2 vs PBS group (473.69±164.73) μm2, P<0.01].Conclusion Transplantation of HAECs can improve the hindlimb motor function of rats with spinal cord injury.

  1. Radiosensitivity of angiogenic and mitogenic factors in human amniotic membrane

    International Nuclear Information System (INIS)

    Amniotic membrane as a temporary biological dressing remains as a beneficial and cost-effective means of treating burns in developing countries. This medical application is attributed mainly to placental structural and biochemical features that are important for maintaining proper embryonic development. Since fresh amnions are nevertheless for straightforward clinical use and for preservation, radiation-sterilization is been performed to improve the safety of this placental material. However, like any other sterilization method, gamma-radiation may induce physical and chemical changes that may influence the biological property of the material. Thus, the aim of this study is to compare the effects of various levels of radiation-sterilization protocols for human amnions on angiogenic (neovascularization) and epithelial-mitogenic activities, both of which are physiological processes fundamental to wound healing. Water-soluble extract of non-irradiated amnions demonstrates a strong stimulatory effect on both cell proliferation and angiogenesis. No change in biological activity is seen in amnions irradiated at 25 kGy, the sterilization dose used by the Philippine Nuclear Research Institute (PNRI) for the production of radiation-sterilized human amniotic membranes (RSHAM). However, it appears that amniotic angiogenic factors are more radiosensitive than its mitogenic components, evident from the depressed vascularization of the chorioallantoic membrane (CAM) exposed to 35 kGy-irradiated amnions. The dose of 35 kGy is at present the medical sterilization dose used at the Central Tissue Bank in Warsaw (Poland) for the preparation of their amnion allografts. (Authors)

  2. 足月妊娠羊水过少患者羊膜和胎盘的组织病理学及组织化学变化%Histopathology and Histochemistry Changes of Amnion and Placenta with Oligohydramnios in Full Term Pregnancy

    Institute of Scientific and Technical Information of China (English)

    石凡华

    2015-01-01

    Objective:To explore the histopathologic and histochemistic changes of amniotic membrane and placenta with oligohydramnios in term pregnancy.Method:Amniotic membrane and placenta with normal amount amniotic fluid and oligohydramnios 15 cases in each group.The martial undergone fixation with 10% formaldehyde and routine paraffin section, HE staining and AB-PAS reaction.The slices were observed under light microscope and some index of the morphomatry acquired.Result:The amniotic cells of oligohydramnios became shriek and vesicle, even stratified metaplasia, PAS granules were reduced in their cytoplasm.Syncytail knots increased.AB-PAS reaction became weaken because of glycogen granules in cytoplasm were rare, the basement membrane of the capillaries at the villi became vary thinker, all these changes point on aging and disfunction.Conclusion:The histopathologic changes and glycogen reduce in amniotic cells, and number of syncytail knot raise, thinker vasculosyncytial membrane and rare glycogen et al in placenta villi take part in the pathological and physiological process of the oligohydramnios.%目的:探讨足月妊娠羊水过少患者的羊膜和胎盘的组织化学反应变化。方法:取足月分娩正常量羊水和羊水过少患者的羊膜和胎盘各15例,标本经10%甲醛固定,常规石蜡制片,分别进行HE和阿利新蓝-多糖(AB-PAS)法染色,光镜观察并进行形态计量学分析。结果:羊水过少羊膜细胞出现固缩、空泡变甚至鳞状化生,胞质内PAS阳性颗粒减少;胎盘滋养层细胞PAS反应明显减弱阳性颗粒缺失,合体结节增多,绒毛中轴毛细血管基膜多增厚,血管合体膜增厚等。结论:羊膜上皮形变、老化,糖原缺乏、血管合体膜增厚、合体结节增多,参与羊水过少的病理生理过程。

  3. Cat amniotic membrane multipotent cells are nontumorigenic and are safe for use in cell transplantation

    OpenAIRE

    Vidane AS; Souza AF; Sampaio RV; Bressan FF; Pieri NC; Martins DS; Meirelles FV; Miglino MA; Ambrósio CE

    2014-01-01

    Atanasio S Vidane,1 Aline F Souza,1 Rafael V Sampaio,1 Fabiana F Bressan,2 Naira C Pieri,1 Daniele S Martins,2 Flavio V Meirelles,2 Maria A Miglino,1 Carlos E Ambrósio2 1Department of Surgery, Faculty of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, Brazil; 2Department of Veterinary Medicine, Faculty of Animal Sciences and Food Engineering, University of São Paulo, São Paulo, Brazil Abstract: Amnion-derived ...

  4. 组织工程上皮移植对碱烧伤角膜新生血管的影响%Tissue-engineered epithelium transplantation on corneal neovascularization in alkali-induced limbal stem cell deficiency

    Institute of Scientific and Technical Information of China (English)

    郭青; 皮裕琍

    2012-01-01

    目的:评价组织工程上皮移植在碱烧伤角膜缘干细胞缺乏症中对角膜新生血管的抑制作用.方法:回顾性非随机的病例研究.2006/2011年我院收治的19例(23眼)完全性角膜缘干细胞缺乏症的碱烧伤患者,10例13眼行组织工程上皮移植,9例10眼行羊膜移植.所有患者在手术前后均用裂隙灯观察角膜新生血管情况,在术后第21,60d对角膜新生血管进行评分比较.结果:术后第21d和术后第60d组织工程上皮移植组和羊膜移植组角膜新生血管均较术前明显减少( P<0.05),在术后两个评价时间点,组织工程上皮移植组平均角膜新生血管分数明显低于羊膜移植组.结论:对碱烧伤所致角膜缘干细胞缺乏的患者,组织工程上皮移植抑制角膜新生血管的作用明显好于羊膜移植.%AIM: To evaluate the clinical outcomes of tissue-engineered epithelium transplantation on decreasing corneal neovascularization in patients with limbal stem cell deficiencies caused by alkali burns.eyes of 19 cases with severe corneal alkali burns from 2006 to 2011 in our hospital. All of these eyes had complete limbal stem cell deficiencies. Ten cases (13 eyes) were performed with tissue-engineered epithelium transplantation, and 9 cases (10 eyes) were performed with amnion membrane transplantation. Vascularization was observed in all cases by slit-lamp microscope before and after surgery. A neovascularization scoring system was used to evaluate each eye at the 21th and 60th after surgery.transplantation or amniotic membrane transplantation was performed, corneal neovascularization decreased significantly (P<0.05). And averaged scores of corneal neovascularization were significantly lower in tissue-engineered epithelium transplantation group at the 21th day and 60th day after surgery than those of amniotic membrane transplantation group(P<0.05). inhibitting the growth of corneal neovascularization in patients with limbal stem cell deficiencies

  5. Morphological analysis of amnion stored in glycerol sterilized with different doses of ionizing radiation

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Fernando Augusto N.; Santin, Stefany P.; Martino Junior, Antonio C.; Machado, Luci Diva B.; Mathor, Monica B., E-mail: fernandonevessoares@yahoo.com.br [Instituto de Pesquisas Energeticas e Nucleares (CTR/IPEN/CNEN-SP), Sao Paulo, RJ (Brazil). Centro de Tecnologia das Radiacoes

    2013-07-01

    The amniotic membrane (AM) is the innermost layer of the fetal membranes (placenta), widely used in transplantation being a tissue that combines anti-inflammatory, antimicrobial and antifibrotic, and limited immunogenicity. The tissue can be used a bandage biological for treatment of burns and skin wounds, chronic ulcers, reconstructions from different body areas, including ophthalmic repairs. In the last decades the amniotic membrane has been used widely also as a carrier substrate to transfer tissues cultured 'in vitro'. The use of fresh membrane has some limitations, the main ones are being necessary your quick use and the inability to obtain full security for certain infections. Other types of preservation require a processing thereof. The radiosterilization is an alternative for ensuring quality and safety of tissues used in transplants, and other clinical applications in order to minimize the risk of contamination of the receptor tissue. Therefore, the objective of this study was to test various doses of radiation using two sources of ionizing radiation: the cobalt-60 irradiator Gamma and Electron Beam Accelerator (E.B.). A tissue analysis was done by visual and tactile qualitative analysis, semi-quantitative (solid colorimetry) and light microscopy to observe morphological and physic-chemical changes after the irradiation of AM preserved in glycerol, comparing the results obtained with the sample not irradiated. It was noted that at higher doses, for both radiation sources, irradiated membranes suffered greater color change, becoming yellowish and thereby reducing their initial malleability. (author)

  6. Periostin as a Biomarker of the Amniotic Membrane

    Directory of Open Access Journals (Sweden)

    Mariya P. Dobreva

    2012-01-01

    Full Text Available Tracing the precise developmental origin of amnion and amnion-derived stem cells is still challenging and depends chiefly on analyzing powerful genetic model amniotes like mouse. Profound understanding of the fundamental differences in amnion development in both the disc-shaped primate and human embryo and the cup-shaped mouse embryo is pivotal in particular when sampling amniotic membrane from nonprimate species for isolating candidate amniotic stem cells. The availability of molecular marker genes that are specifically expressed in the amniotic membrane and not in other extraembryonic membranes would be instrumental to validate unequivocally the starting material under investigation. So far such amniotic markers have not been reported. We postulated that bone morphogenetic protein (BMP target genes are putative amniotic membrane markers mainly because deficiency in one of several components of the BMP signaling cascade in mice has been documented to result in defective development of the early amnion. Comparative gene expression analysis of acknowledged target genes for BMP in different extraembryonic tissues, combined with in situ hybridization, identified Periostin (Postn mRNA enrichment in amnion throughout gestation. In addition, we identify and propose a combination of markers as transcriptional signature for the different extraembryonic tissues in mouse.

  7. 人脐血间充质干细胞修复大鼠坐骨神经损伤的实验研究%Experiment research of the function of human umbilical cord blood mesenchymal stem cells in the regeneration of rat's sciatic nerve

    Institute of Scientific and Technical Information of China (English)

    王忠仁; 杨波; 王利民; 李恩

    2009-01-01

    Objective To evaluate the efectiveness of using mesenchymal stem cells(MSCs)derived from HUCB(human umbilical cord blood)to a tissue engineered bioartificial nerve on bridging a 1 0 mm sciatic nerve gap.Methods The cord blood mononuclear cells were isolated by lymphocyte separation medium,purified and expanded with MesencultTM medium and acidic environment to produce adherent layer(MSCs).Thirty SD female rats were randomly divided into three groups.Group A:Human amnion tubes were seeded by HUCBMSCs together with fibrin sealant.Group B:Human amnion tubes were seeded only with fibrin sealant.group C:autografts.9 weeks later,a series of examinations were performed which included morphological,sciatic nerve function index,weight of gastrocnemius,histological staining and immunostaining of S100.Results The HUCB-derived mononuclear cells,when seeded in specific medium,gave rise to adherent cells (MSCs).At 9 weeks after the operations,all the examinations of group A was better than group B(P<0.05).Conclusion HUCBMSCs can be isolated,purified, cultivated and expanded Mesencult~(TM) medium.HUCBMSCs can promote the nerve to regenerate in reparing the sciatic nerve gap.%目的 评价用人脐血间充质干细胞(HUCBMSCs)构建组织工程化人工神经修复大鼠坐骨神经10 mm缺损的治疗效果. 方法 用淋巴细胞分离液分离脐血的单个核细胞,以偏酸性的MesencultTM进行培养获得MSCs.30只SD大鼠随机分为3组,每组10只.A组:将HUCBMSCs与生物蛋白胶混合,种植于羊膜管中修复坐骨神经缺损;B组:仅将生物蛋白胶种植于羊膜管中:C组:坐骨神经切下后再将其缝合.9周后,行大体观察、坐骨神经功能指数、腓肠肌湿重测定、组织学染色,S100免疫组化染色等检查. 结果 32份脐血18份可培养出MSCs,但传代培养大量扩增只有4份.HUCBMSCs植人手术后9周检查结果显示,坐骨神经功能指数、腓肠肌湿重测定A组(-64.2234±2.9461、41.29524±3.88421)

  8. Stem Cells

    Science.gov (United States)

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

  9. Concurrent conjunctivitis and placentitis in aborted bovine fetuses.

    Science.gov (United States)

    Murray, R D

    1991-11-01

    Consistent histopathological lesions were found in 10 out of 136 aborted fetuses examined during a three year period, using a multi-disciplinary diagnostic investigation technique. Fetuses exhibited a generalized mononuclear inflammatory cell infiltration, accompanied by distinctive lesions of conjunctival hyperplasia and goblet cell formation, alveolitis, and necrotic placentitis. In two cases where amnion was also examined, a chronic amnionitis was present. No consistent laboratory findings could be related to these cases. The fetal and placental lesions described were similar to those associated with experimental inoculation of Ureaplasma diversum in pregnant cows, and with field isolations of the same organism in aborting cattle.

  10. T Cells

    Science.gov (United States)

    T Cells - National Multiple Sclerosis Society Skip to navigation Skip to content Menu Navigation National Multiple Sclerosis Society Sign ... Is MS? Definition of MS T Cells T Cells Share Smaller Text Larger Text Print In this ...

  11. Cell counting.

    Science.gov (United States)

    Phelan, M C; Lawler, G

    2001-05-01

    This unit presents protocols for counting cells using either a hemacytometer or electronically using a Coulter counter. Cell counting with a hemacytometer permits effective discrimination of live from dead cells using trypan blue exclusion. In addition, the procedure is less subject to errors arising from cell clumping or size heterogeneity. Counting cells is more quickly and easily performed using an electronic counter, but live-dead discrimination is unreliable. Cell populations containing large numbers of dead cells and/or cell clumps are difficult to count accurately. In addition, electronic counting requires resetting of the instrument for cell populations of different sizes; heterogeneous populations can give rise to inaccurate counts, and resting and activated cells may require counting at separate settings. In general, electronic cell counting is best performed on fresh peripheral blood cells. PMID:18770655

  12. Zinc ferrite nanoparticles activate IL-1b, NFKB1, CCL21 and NOS2 signaling to induce mitochondrial dependent intrinsic apoptotic pathway in WISH cells

    Energy Technology Data Exchange (ETDEWEB)

    Saquib, Quaiser; Al-Khedhairy, Abdulaziz A.; Ahmad, Javed; Siddiqui, Maqsood A.; Dwivedi, Sourabh; Khan, Shams T. [Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Chair for DNA Research, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Musarrat, Javed, E-mail: musarratj1@yahoo.com [Chair for DNA Research, Department of Zoology, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Department of Agricultural Microbiology, Faculty of Agricultural Sciences, Aligarh Muslim University, Aligarh 202002, U.P. (India)

    2013-12-01

    The present study has demonstrated the translocation of zinc ferrite nanoparticles (ZnFe{sub 2}O{sub 4}-NPs) into the cytoplasm of human amnion epithelial (WISH) cells, and the ensuing cytotoxicity and genetic damage. The results suggested that in situ NPs induced oxidative stress, alterations in cellular membrane and DNA strand breaks. The [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] (MTT) and neutral red uptake (NRU) cytotoxicity assays indicated 64.48 ± 1.6% and 50.73 ± 2.1% reduction in cell viability with 100 μg/ml of ZnFe{sub 2}O{sub 4}-NPs exposure. The treated WISH cells exhibited 1.2-fold higher ROS level with 0.9-fold decline in membrane potential (ΔΨm) and 7.4-fold higher DNA damage after 48 h of ZnFe{sub 2}O{sub 4}-NPs treatment. Real-time PCR (qPCR) analysis of p53, CASP 3 (caspase-3), and bax genes revealed 5.3, 1.6, and 14.9-fold upregulation, and 0.18-fold down regulation of bcl 2 gene vis-à-vis untreated control. RT{sup 2} Profiler™ PCR array data elucidated differential up-regulation of mRNA transcripts of IL-1b, NFKB1, NOS2 and CCL21 genes in the range of 1.5 to 3.7-folds. The flow cytometry based cell cycle analysis suggested the transfer of 15.2 ± 2.1% (p < 0.01) population of ZnFe{sub 2}O{sub 4}-NPs (100 μg/ml) treated cells into apoptotic phase through intrinsic pathway. Over all, the data revealed the potential of ZnFe{sub 2}O{sub 4}-NPs to induce cellular and genetic toxicity in cells of placental origin. Thus, the significant ROS production, reduction in ΔΨm, DNA damage, and activation of genes linked to inflammation, oxidative stress, proliferation, DNA damage and repair could serve as the predictive toxicity and stress markers for ecotoxicological assessment of ZnFe{sub 2}O{sub 4}-NPs induced cellular and genetic damage. - Highlights: • First report on the molecular toxicity of ZnFe{sub 2}O{sub 4}-NPs in cells of placental origin • WISH cells treated with ZnFe{sub 2}O{sub 4}-NPs exhibited cytoplasmic

  13. 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)

  14. 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

  15. Cell Wall

    OpenAIRE

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

    2008-01-01

    This chapter covers our present knowledge of cell wall proteomics highlighting the distinctive features of cell walls and cell wall proteins in relation to problems encountered for protein extraction, separation and identification. It provides clues to design strategies for efficient cell wall proteomic studies. It gives an overview of the kinds of proteins that have yet been identified: the expected proteins vs the identified proteins. Finally, the new vision of the cell wall proteome, and t...

  16. Stem Cells

    OpenAIRE

    Madhukar Thakur

    2009-01-01

    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 ...

  17. 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.

  18. 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.

  19. Surfactant Protein-A as an Anti-Inflammatory Component in the Amnion: Implications for Human Pregnancy1

    OpenAIRE

    Lee, Deug-Chan; Romero, Roberto; Kim, Chong Jai; Chaiworapongsa, Tinnakorn; Tarca, Adi L.; Lee, JoonHo; Suh, Yeon-Lim; Mazaki-Tovi, Shali; Vaisbuch, Edi; Mittal, Pooja; Draghici, Sorin; Erez, Offer; Kusanovic, Juan Pedro; Hassan, Sonia S; Kim, Jung-Sun

    2010-01-01

    The mechanism of mouse parturition is thought to involve myometrial infiltration by amniotic fluid (AF) macrophages, activated by surfactant protein-A (SP-A). In humans, the concentration of AF SP-A decreases during labor, and no fetal macrophages are found in the myometrium after labor. Therefore, it appears that the mechanisms of labor in mice and humans are different. We investigated a potential role for SP-A in human pregnancy and parturition by examining SP-A expression patterns in AF an...

  20. 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

  1. Solar cells

    Science.gov (United States)

    Cuquel, A.; Roussel, M.

    The physical and electronic characteristics of solar cells are discussed in terms of space applications. The principles underlying the photovoltaic effect are reviewed, including an analytic model for predicting the performance of individual cells and arrays of cells. Attention is given to the effects of electromagnetic and ionizing radiation, micrometeors, thermal and mechanical stresses, pollution and degassing encountered in space. The responses of different types of solar cells to the various performance-degrading agents are examined, with emphasis on techniques for quality assurance in the manufacture and mounting of Si cells.

  2. 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...

  3. Optimization of In Vitro Culture Conditions for Human Amniotic Epithelial Cells and Expression of Stem Cell Markers%羊膜上皮细胞体外培养条件的优化及其干细胞标志的表达

    Institute of Scientific and Technical Information of China (English)

    陈宥艺; 陆琰; 王科; 王琰; 吴东颖; 刘兵; 杨瑛; 吕双红

    2011-01-01

    本研究优化人足月胎盘羊膜上皮细胞(human amniotic epithelium cells,hAEC)的体外培养方法并现察hAEC的干细胞标志的表达情况.取健康产妇足月剖宫产术后的羊膜,采用胰酶多次消化获取hAEC,分别应用10% FBS的DMEM、类似胚胎干细胞的培养条件及添加表皮细胞生长因子(epidermal growth factor,EGF)的类似胚胎干细胞的培养条件对其进行原代和传代培养,观察培养后细胞形态,并通过流式细胞术检测、细胞免疫荧光染色等方法对培养细胞的干细胞多能性标志进行鉴定.结果表明:在类似胚胎干细胞培养条件的基础上添加10 ng/ml EGF可提高hAEC原代细胞的贴壁率和增殖能力,与广泛应用的10% FBS的DMEM培养条件相比,在此培养条件下细胞传代能力显著增强,传至5代仍保持上皮细胞表型,细胞形态在传代过程中改变不明显,并且表达胚胎干细胞全能性的表面标志SSEA-4同时细胞免疫荧光染色显示培养后的hAEC表达波形蛋白(vimentin).结论:采用类似胚胎干细胞的培养条件有利于hAEC在体外的扩增和传代,EGF对其增殖和传代有促进作用,培养的hAEC表达胚胎干细胞多能性标志.%This study was purposed to optimize the culture conditions of the human amniotic epithelium cells (hAEC) in vitro, and detect the expression of hAEC pluripotent markers.Amnion tissues were separated from the underlying chorion through the spongy layer immediately after elective cesarean section of healthy pregnancy women at term.After the subsequent exposure to trypsin digestion, hAEC were cultured in DMEM with different supplements.The growth and proliferation potential of hAEC was evaluated, and the expression of cultured hAEC pluripotent markers was detected by using flow cytometry and immunohistochemistry methods.The results indicated that when being cultured in the mediums similar to that of embryonic stem cell culture supplemented with 10 ng/ml EGF, the h

  4. 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

  5. Types of Stem Cells

    Science.gov (United States)

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... stem cells blog from the International Society for Stem Cell Research. Learn About Stem Cells From Lab to You ...

  6. Fuel Cells

    DEFF Research Database (Denmark)

    Smith, Anders; Pedersen, Allan Schrøder

    2014-01-01

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

  7. Cell suicide

    International Nuclear Information System (INIS)

    In the fight of the cell against the damages caused to its DNA by genotoxic agents and specially by ionizing radiations, the p53 protein plays a central part. It intervenes in the proliferation control and the differentiation but also in the keeping of genome integrity. It can direct the damages cells toward suicide, or apoptosis, to avoid the risk of tumor appearance that would be fatal to the whole organism. That is by the disordered state of cells suicide programs that the tumor cells are going to develop. The knowledge of apoptosis mechanisms, to eventually start them on demand, rises up broad hopes in the cancer therapy. (N.C.)

  8. Invasiveness and Ploidy of Human Mammary Carcinomas in Short-Term Culture

    Science.gov (United States)

    Smith, Helene S.; Liotta, Lance A.; Hancock, Miriam C.; Wolman, Sandra R.; Hackett, Adeline J.

    1985-03-01

    Invasiveness and ploidy were examined in cultures of human epithelial cells derived from nonmalignant breast tissue, primary breast carcinomas, and breast cancer effusion metastases. Successful short-term culture was achieved from approximately 70% of the primary breast cancers. These primary cancers were essentially diploid by flow cytometry and karyotype in contrast to the effusion metastases, which were mostly aneuploid. The diploid tumor cells retained their malignant phenotype in culture as demonstrated by invasion into a denuded human amnion basement membrane. In contrast, epithelial cells cultured from nonmalignant mammary tissue did not invade the amnion. We suggest that the diploid carcinoma cultures may be useful for investigating the essential differences between normal and malignant cells and may complement information derived from studies of tumor cell lines with grossly aberrant karyotypes.

  9. Reprogrammed Pluripotent Stem Cells from Somatic Cells

    OpenAIRE

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-01-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-li...

  10. 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)

  11. Neural Differentiation of Human Umbilical Cord Mesenchymal Stem Cells by Cerebrospinal Fluid

    Directory of Open Access Journals (Sweden)

    Shirin FARIVAR*

    2015-01-01

    chick embryos. J Exp Zool A Comp Exp Biol 2004 Apr 1;301(4:280-9.Mitchell KE, Weiss ML. Matrix cells from Wharton’s jelly form neurons and glia. Stem Cells 2003;21(1:50-60.Marcus AJ, Woodbury D. Fetal stem cells from extra-embryonic tissues: do not discard. J Cell Mol Med 2008 Jun;12(3:730-42. doi: 10.1111/j.1582- 4934.2008.00221.x. Epub 2008 Jan 11.Miao Z, Jin J, Chen L, Zhu J, Huang W, Zhao J, Quian H, Zhang X. Isolation of mesenchymal stem cells from human placenta: comparison with human bone marrow mesenchymal stem cells. Cell Biol Int 2006 Sep;30(9:681-7. Epub 2006 Apr 22.In ‘tAnker PS, Scherjon SA, Kleijburg-van der Keur C, Noort WA, Claas FHJ, Willemze R, Fibbe WE, Kanhai HHH. Amniotic fluid as a novel source of mesenchymal stem cells for therapeutic transplantation. Blood 2003;102(4:1548-49.Magatti M, De Munari S, Vertua E, Gibelli L, Wengler GS, Parolini O. Human amnion mesenchyme harbors cells with allogeneic T-cell suppression and stimulation capabilities. Stem Cells 2008 Jan;26(1:182-92. Epub 2007 Sep 27.Kang XQ, Zang WJ, Bao LJ, Li DL, Xu XL, Yu XJ. Differentiating characterization of human umbilical cord blood-derived mesenchymal stem cells in vitro. Cell Biol Int 2006 Jul;30(7:569-75. Epub 2006 Mar 6.Kern S, Eichler H, Stoeve J, Kluter H, Bieback K. Comparative analysis of mesenchymal stem cells from bone marrow, umbilical cord blood, or adipose tissue. Stem Cells 2006 May;24(5:1294-301. Epub 2006 Jan 12.Wagner W, Wein F, Seckinger A, Frankhauser M, Wirkner U, Krause U, et al. Comparative characteristics of mesenchymal stem cells from human bone marrow, adipose tissue, and umbilical cord blood. Exp Hematol 2005 Nov;33(11:1402-16.Jackson JS, Golding JP, Chapon C, Jones WA, Bhakoo KK: Homing of stem cells to sites of inflammatory brain injury after intracerebral and intravenous administration: a longitudinal imaging study. Stem Cell Res Ther 2010 Jun 15;1(2:17. doi: 10.1186/scrt17.Romanov YA, Svintsitskaya VA, Smirnov VN. Searching for alternative

  12. [Cell cultures].

    Science.gov (United States)

    Cipro, Simon; Groh, Tomáš

    2014-01-01

    Cell or tissue cultures (both terms are interchangeable) represent a complex process by which eukaryotic cells are maintained in vitro outside their natural environment. They have a broad usage covering not only scientific field but also diagnostic one since they represent the most important way of monoclonal antibodies production which are used for both diagnostic and therapeutic purposes. Cell cultures are also used as a "cultivation medium" in virology and for establishing proliferating cells in cytodiagnostics. They are well-established and easy-to-handle models in the area of research, e.g. as a precious source of nucleic acids or proteins. This paper briefly summarizes their importance and methods as well as the pitfalls of the cultivation and new trends in this field. PMID:24624984

  13. 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.

  14. 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 ...

  15. Cell sorting by deterministic cell rolling

    OpenAIRE

    Choi, Sungyoung; Karp, Jeffrey M.; Karnik, Rohit

    2011-01-01

    This communication presents the concept of “deterministic cell rolling”, which leverages transient cell-surface molecular interactions that mediate cell rolling to sort cells with high purity and efficiency in a single step.

  16. Electrochemical cell

    Science.gov (United States)

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

    1992-01-01

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

  17. The Amniotic Membrane: Development and Potential Applications - A Review.

    Science.gov (United States)

    Favaron, P O; Carvalho, R C; Borghesi, J; Anunciação, A R A; Miglino, M A

    2015-12-01

    Foetal membranes are essential tissues for embryonic development, playing important roles related to protection, breathing, nutrition and excretion. The amnion is the innermost extraembryonic membrane, which surrounds the foetus, forming an amniotic sac that contains the amniotic fluid (AF). In recent years, the amniotic membrane has emerged as a potential tool for clinical applications and has been primarily used in medicine in order to stimulate the healing of skin and corneal diseases. It has also been used in vaginal reconstructive surgery, repair of abdominal hernia, prevention of surgical adhesions and pericardium closure. More recently, it has been used in regenerative medicine because the amniotic-derived stem cells as well as AF-derived cells exhibit cellular plasticity, angiogenic, cytoprotective, immunosuppressive properties, antitumoural potential and the ability to generate induced pluripotent stem cells. These features make them a promising source of stem cells for cell therapy and tissue engineering. In this review, we discussed the development of the amnion, AF and amniotic cavity in different species, as well as the applicability of stem cells from the amnion and AF in cellular therapy.

  18. Solar cells

    Science.gov (United States)

    Treble, F. C.

    1980-11-01

    The history, state of the art, and future prospects of solar cells are reviewed. Solar cells are already competitive in a wide range of low-power applications, and during the 1980's they are expected to become cheaper to run than diesel or gasoline generators, the present mainstay of isolated communities. At this stage they will become attractive for water pumping, irrigation, and rural electrification, particularly in developing countries. With further cost reduction, they may be used to augment grid supplies in domestic, commercial, institutional, and industrial premises. Cost reduction to the stage where photovoltaics becomes economic for large-scale power generation in central stations depends on a technological breakthrough in the development of thin-film cells. DOE aims to reach this goal by 1990, so that by the end of the century about 20% of the estimated annual additions to their electrical generating capacity will be photovoltaic.

  19. Stem Cells

    DEFF Research Database (Denmark)

    Sommerlund, Julie

    2004-01-01

    In his influential essay on markets, An essay on framing and overflowing (1998), Michel Callon writes that `the growing complexity of industrialized societies [is] due in large part to the movements of the technosciences, which are causing connections and interdependencies to proliferate'. This p...... and tantalizing than stem cells, in research, in medicine, or as products.......'. 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...

  20. Cell Libraries

    Science.gov (United States)

    1994-01-01

    A NASA contract led to the development of faster and more energy efficient semiconductor materials for digital integrated circuits. Gallium arsenide (GaAs) conducts electrons 4-6 times faster than silicon and uses less power at frequencies above 100-150 megahertz. However, the material is expensive, brittle, fragile and has lacked computer automated engineering tools to solve this problem. Systems & Processes Engineering Corporation (SPEC) developed a series of GaAs cell libraries for cell layout, design rule checking, logic synthesis, placement and routing, simulation and chip assembly. The system is marketed by Compare Design Automation.

  1. Solar cells

    International Nuclear Information System (INIS)

    A method of producing solar cells is described which consists of producing a substantially monocrystalline tubular body of silicon or other suitable semiconductor material, treating this body to form an annular rectifying junction and then cutting it longitudinally to form a number of nearly flat ribbons from which the solar cells are fabricated. The P=N rectifying junction produced by the formation of silicon dioxide on the layers at the inner and outer surfaces of the body can be formed by ion-implantation or diffusion. (U.K.)

  2. Learn About Stem Cells

    Science.gov (United States)

    ... PDF) Download an introduction to stem cells and stem cell research. Stem Cell Glossary Stem cell terms to know. ... ISSCR Get Involved Media © 2015 International Society for Stem Cell Research Terms of Use Disclaimer Privacy Policy

  3. Stem Cell Basics

    Science.gov (United States)

    ... Information Stem Cell Basics Stem Cell Basics: Introduction Stem Cell Information General Information Clinical Trials Funding Information Current Research Policy Glossary Site Map Stem Cell Basics Introduction: What are stem cells, and why ...

  4. Stem Cell Information: Glossary

    Science.gov (United States)

    ... Neurons Oligodendrocyte Parthenogenesis Passage Pluripotent Polar body Preimplantation Proliferation Regenerative medicine Reproductive cloning Signals Somatic cell Somatic cell nuclear transfer (SCNT) Somatic (adult) stem cell Stem cells Stromal cells Subculturing Surface markers ...

  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 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 nuclear fuel-based energy technologies....

  7. 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…

  8. 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

  9. Cell Docking, Movement and Cell-Cell Interactions of Heterogeneous Cell Suspensions in a Cell Manipulation Microdevice

    OpenAIRE

    Long-Sun Huang; Yu-Hung Wang; Yu-Wei Chung; Fei-Lung Lai; Shiaw-Min Hwang

    2011-01-01

    This study demonstrates a novel cell manipulation microdevice for cell docking, culturing, cell-cell contact and interaction by microfluidic manipulation of heterogeneous cell suspensions. Heterogeneous cell suspensions include disparate blood cells of natural killer cells and leukemia cancer cells for immune cell transplantation therapy. However, NK cell alloreactivity from different healthy donors present various recovery response levels. Little is still known about the interactions and cyt...

  10. Reprogrammed pluripotent stem cells from somatic cells.

    Science.gov (United States)

    Kim, Jong Soo; Choi, Hyun Woo; Choi, Sol; Do, Jeong Tae

    2011-06-01

    Pluripotent stem cells, such as embryonic stem (ES) cells, can differentiate into all cell types. So, these cells can be a biological resource for regenerative medicine. However, ES cells known as standard pluripotent cells have problem to be used for cell therapy because of ethical issue of the origin and immune response on the graft. Hence, recently reprogrammed pluripotent cells have been suggested as an alternative source for regenerative medicine. Somatic cells can acquire the ES cell-like pluripotency by transferring somatic cell nuclei into oocytes, by cell fusion with pluripotent cells. Retroviral-mediated introduction of four factors, Oct4, Sox2, Klf4 and c-Myc can successfully reprogram somatic cells into ES cell-like pluripotent stem cells, known as induced pluripotent stem (iPS) cells. These cells closely resemble ES cells in gene expression pattern, cell biologic and phenotypic characteristics. However, to reach the eventual goal of clinical application, it is necessary to overcome the major drawbacks such as low reprogramming efficiency and genomic alterations due to viral integration. In this review, we discuss the current reprogramming techniques and mechanisms of nuclear reprogramming induced by transcription factor transduction. PMID:24298328

  11. 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.

  12. Murine Mueller cells are progenitor cells for neuronal cells and fibrous tissue cells

    International Nuclear Information System (INIS)

    Mammalian Mueller cells have been reported to possess retinal progenitor cell properties and generate new neurons after injury. This study investigates murine Mueller cells under in vitro conditions for their capability of dedifferentiation into retinal progenitor cells. Mueller cells were isolated from mouse retina, and proliferating cells were expanded in serum-containing medium. For dedifferentiation, the cultured cells were transferred to serum-replacement medium (SRM) at different points in time after their isolation. Interestingly, early cell passages produced fibrous tissue in which extracellular matrix proteins and connective tissue markers were differentially expressed. In contrast, aged Mueller cell cultures formed neurospheres in SRM that are characteristic for neuronal progenitor cells. These neurospheres differentiated into neuron-like cells after cultivation on laminin/ornithine cell culture substrate. Here, we report for the first time that murine Mueller cells can be progenitors for both, fibrous tissue cells and neuronal cells, depending on the age of the cell culture

  13. Sickle Cell Information Center

    Science.gov (United States)

    ... Around the Web Google Custom Search – sickle cell Sickle Cell Anemia - In-Depth Report - NY Times Health January 18, 1970 Sickle cell disease (also called sickle cell anemia) is an inherited blood disorder that affects red ...

  14. 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.

  15. What are Stem Cells?

    OpenAIRE

    Ahmadshah Farhat; Ashraf Mohammadzadeh; M. Rezaie

    2014-01-01

      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 ...

  16. Pluripotent stem cell lines

    OpenAIRE

    Yu, Junying; Thomson, James A.

    2008-01-01

    The derivation of human embryonic stem cells 10 years ago ignited an explosion of public interest in stem cells, yet this achievement depended on prior decades of research on mouse embryonic carcinoma cells and embryonic stem cells. In turn, the recent derivation of mouse and human induced pluripotent stem cells depended on the prior studies on mouse and human embryonic stem cells. Both human embryonic stem cells and induced pluripotent stem cells can self-renew indefinitely in vitro while ma...

  17. DNA-cell conjugates

    Energy Technology Data Exchange (ETDEWEB)

    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. Distribution of CA 125 in placental tissues.

    Science.gov (United States)

    Fuith, L C; Müller-Holzner, E; Marth, C; Perkmann, E; Zeimet, A; Daxenbichler, G

    1989-01-01

    The presence of the tumor marker CA 125 was studied in different compartments of the human placenta. Levels of CA 125 in the cytosol of chorionic villi ranged from 27-17100 U/g (median 560 U/g). In the placental amnion and chorion concentrations ranged from 175-29000 U/g, median 1060 U/g and were not statistically different. In the umbilical cord values were significantly lower (range 44-7600 U/g; median 180 U/g). Maternal serum probes were above the upper limit of normal in all cases (range 48-500 U/ml; median 131 U/ml). Immunohistochemistry detected CA 125 exclusively within the amniotic cells of the placenta and the umbilical cord. This might be because CA 125 fixes more to insoluble structures in the amnion or because of contamination of chorionic villi with the underlying decidua.

  19. 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.

  20. 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

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

    OpenAIRE

    He, M-f; S. Wang; 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...

  2. Monitoring cell growth.

    Science.gov (United States)

    Strober, W

    2001-05-01

    This appendix provides two protocols for monitoring cell growth. Counting cells using a hemacytometer is tedious but it allows one to effectively distinguish live cells from dead cells (using Trypan Blue exclusion). In addition, this procedure is less subject to errors due to cell clumping or heterogeneity of cell size. The use of an electronic cell counter is quicker and easier than counting cells using a hemacytometer. However, an electronic cell counter as currently constructed does not distinguish live from dead cells in a reliable fashion and is subject to error due to the presence of cell clumps. Overall, the electronic cell counter is best reserved for repetitive and rapid counting of fresh peripheral blood cells and should be used with caution when counting cell populations derived from tissues. PMID:18432653

  3. Automated Cell-Cutting for Cell Cloning

    Science.gov (United States)

    Ichikawa, Akihiko; Tanikawa, Tamio; Matsukawa, Kazutsugu; Takahashi, Seiya; Ohba, Kohtaro

    We develop an automated cell-cutting technique for cell cloning. Animal cells softened by the cytochalasin treatment are injected into a microfluidic chip. The microfluidic chip contains two orthogonal channels: one microchannel is wide, used to transport cells, and generates the cutting flow; the other is thin and used for aspiration, fixing, and stretching of the cell. The injected cell is aspirated and stretched in the thin microchannel. Simultaneously, the volumes of the cell before and after aspiration are calculated; the volumes are used to calculate the fluid flow required to aspirate half the volume of the cell into the thin microchannel. Finally, we apply a high-speed flow in the orthogonal microchannel to bisect the cell. This paper reports the cutting process, the cutting system, and the results of the experiment.

  4. 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 a crescent or sickle. They ... last as long as normal, round red blood cells. This leads to anemia. The sickle cells also ...

  5. 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)

  6. 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.

  7. Sickle cell anemia - resources

    Science.gov (United States)

    Resources - sickle cell anemia ... The following organizations are good resources for information on sickle cell anemia : American Sickle Cell Anemia Association -- www.ascaa.org National Heart, Blood, and Lung Institute -- www. ...

  8. Sickle Cell Disease

    Science.gov (United States)

    ... 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 » ... are affected by sickle cell disease. More WEBINAR ...

  9. Sickle Cell Disease

    Science.gov (United States)

    ... from the NHLBI on Twitter. What Is Sickle Cell Disease? Español The term sickle cell disease (SCD) ... common forms of SCD. Some Forms of Sickle Cell Disease Hemoglobin SS Hemoglobin SC Hemoglobin Sβ 0 thalassemia ...

  10. Squamous cell skin cancer

    Science.gov (United States)

    ... earliest form of squamous cell cancer is called Bowen disease (or squamous cell carcinoma in situ). This type ... cancer; Squamous cell carcinoma of the skin Images Bowen's disease on the hand Keratoacanthoma Keratoacanthoma Skin cancer, squamous ...

  11. 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 ...

  12. 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...

  13. 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 ...

  14. Basal Cell Carcinoma (BCC)

    Science.gov (United States)

    ... epithelioma, is the most common form of skin cancer. Basal cell carcinoma usually occurs on sun-damaged skin, especially ... other health issues. Infiltrating or morpheaform basal cell carcinomas: Infiltrating basal cell carcinomas can be more aggressive and locally destructive ...

  15. Immobilization of cells via activated cell walls

    Energy Technology Data Exchange (ETDEWEB)

    Markt, M.; Kas, J.; Valentova, O.; Demnerova, K.; Vodrazka, Z.

    1986-10-01

    Cell walls of Saccharomyces cerevisiae and S. uvarum were activated by periodate oxidation of vicinal diol groups in cell wall polysaccharides. The aldehyde groups thus generated allow the yeast cells to be covalently bound to modified bead cellulose or macroporous glycidyl methacrylate supports, or to enzymes such as glucose oxidase and catalase. 6 references.

  16. 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

  17. 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.

  18. Artificial Stem Cell Niches

    OpenAIRE

    Lutolf, Matthias P.; Blau, Helen M.

    2009-01-01

    Stem cells are characterized by their dual ability to reproduce themselves (self-renew) and specialize (differentiate), yielding a plethora of daughter cells that maintain and regenerate tissues. In contrast to their embryonic counterparts, adult stem cells retain their unique functions only if they are in intimate contact with an instructive microenvironment, termed stem cell niche. In these niches, stem cells integrate a complex array of molecular signals that, in concert with induced cell-...

  19. Fish Stem Cell Cultures

    OpenAIRE

    Ni Hong, Zhendong Li, Yunhan Hong

    2011-01-01

    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 th...

  20. Stem Cell Separation Technologies

    OpenAIRE

    Zhu, Beili; Murthy, Shashi K

    2013-01-01

    Stem cell therapy and translational stem cell research require large-scale supply of stem cells at high purity and viability, thus leading to the development of stem cell separation technologies. This review covers key technologies being applied to stem cell separation, and also highlights exciting new approaches in this field. First, we will cover conventional separation methods that are commercially available and have been widely adapted. These methods include Fluorescence-activated cell so...

  1. 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.

  2. Clinical application of amniotic membranes on a patient with epidermolysis bullosa.

    Science.gov (United States)

    Martínez Pardo, M E; Reyes Frías, M L; Ramos Durón, L E; Gutiérrez Salgado, E; Gómez, J C; Marín, M A; Luna Zaragoza, D

    1999-01-01

    The case of a patient with dystrophic epidermolysis bullosa treated with radiosterilised amniotic membranes is presented. The disorder is a congenital disease characterised by a poor desmosomal junction in the keratinocyte membrane. After proper donor screening, amnios were collected at Hospital Central Sur de Alta Especialidad (HCSAE), PEMEX and microbiological analysis was performed at Universidad Nacional Autónoma de México, FQUNAM, (Biology Dept. of the Chemistry Faculty, National Autonomous University of Mexico), before and after radiation sterilisation. Processing, packaging and sterilisation were performed at Instituto Nacional de Investigaciones Nucleares, ININ, (National Nuclear Research Institute). The patient, a ten-year-old boy with severe malnutrition, extensive loss of skin and pseudomonad infection in the whole body, was treated with gentle debridement in a Hubbard bath. Later amnion application was performed with sterilised amnios by using two different processes, in one of which the amnion was sterilised with paracetic acid, preserved in glycerol, kindly donated by the German Institute for Tissue and Cell Replacement and applied by Dr. Johannes C. Bruck, IAEA visiting expert, and the other amnion was processed at ININ: air dried and sterilised by gamma radiation at dose of 30 kGy. After spontaneous epithelisation was successfully promoted for seven days, the pain was alleviated and mobility was improved in a few hours and the patient's general condition was so improved that in a month he was discharged. Unfortunately, because this disease is revertive and has malignant degeneration, the prognosis is not good. PMID:10853786

  3. Fusion with stem cell makes the hepatocellular carcinoma cells similar to liver tumor-initiating cells

    OpenAIRE

    Wang, Ran; Chen, Shuxun; Li, Changxian; Ng, Kevin Tak Pan; Kong, Chi-Wing; Cheng, Jinping; Cheng, Shuk Han; Li, Ronald A.; Lo, Chung Mau; Man, Kwan; Sun, Dong

    2016-01-01

    Background Cell fusion is a fast and highly efficient technique for cells to acquire new properties. The fusion of somatic cells with stem cells can reprogram somatic cells to a pluripotent state. Our research on the fusion of stem cells and cancer cells demonstrates that the fused cells can exhibit stemness and cancer cell-like characteristics. Thus, tumor-initiating cell-like cells are generated. Methods We employed laser-induced single-cell fusion technique to fuse the hepatocellular carci...

  4. 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.

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

    International Nuclear Information System (INIS)

    Research highlights: → Four oral squamous cancer cell lines (OSCCL) were analyzed for cancer stem cells (CSCs). → Single cell derived colonies of OSCCL express CSC-marker CD133 differentially. → Monoclonal cell lines showed reduced sensitivity for Paclitaxel. → In situ CD133+ cells are slow cycling (Ki67-) indicating a reduced drug sensitivity. → CD133+ 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+ 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.

  6. Comparative study of effects of magnesium and taurine on electrical parameters of natural and artificial membranes. VII. Effects on cellular and paracellular ionic transfer through isolated human amnion.

    Science.gov (United States)

    Bara, M; Guiet-Bara, A; Durlach, J

    1990-12-01

    The comparative effects of 2 mM magnesium and taurine on various components of the human transamniotic conductance, Gt, were observed. The use of both microelectrodes and metabolic inhibitors enables 10 components of Gt to be distinguished: six cellular components (Na-K ATPase, Na-H antiport, Na-K-2Cl cotransport and Na, K, Cl channels), one coupling component, and three paracellular components (Na, K, Cl). Mg increased all components of Gt while taurine only increased five of them (Na and K channels, coupling, Na and K paracellular conductance). A potentiometric effect of taurine on Mg2+ modified membrane, obtained on paracellular components, was not measured on cellular components. There was only a vicarious effect between Mg and taurine on the non-enzymatic cellular and paracellular transfer of Na and K.

  7. Count of Amnionic Fluid Lamellar Body to Predict the Maturity of Fetal Lung%羊水板层体计数预测胎肺成熟度

    Institute of Scientific and Technical Information of China (English)

    周容; 熊庆; 游永; 周淑; 徐蜀渝; 张静丽; 杜泽丽

    2002-01-01

    目的探讨羊水板层体计数(Lamellar body count, LBC)预测胎肺成熟度的价值. 方法采用库尔特Micro Diff II全自动血细胞分析仪对41例正常足月妊娠剖宫产时的羊水标本进行LBC的测定,并对同一标本采用薄板层析法测定了卵磷脂/鞘磷脂比值(Lecithin-sphingomyelin, L/S比值). 结果(1)正常足月妊娠时羊水LBC为(86±43)×103(范围72.5×103~99.4×103).(2)羊水LBC与L/S比值之间存在正相关,r=0.66,P=0.001. 结论羊水LBC是一种快速、准确地判断肺成熟度的方法.

  8. 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.

  9. SMOOTH MUSCLE STEM CELLS

    Science.gov (United States)

    Vascular smooth muscle cells (SMCs) originate from multiple types of progenitor cells. In the embryo, the most well-studied SMC progenitor is the cardiac neural crest stem cell. Smooth muscle differentiation in the neural crest lineage is controlled by a combination of cell intrinsic factors, includ...

  10. 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 ... or blocks blood and oxygen reaching nearby tissues. Sickle cell disease ... the whites of the eyes) Anemia (the decreased ability of the blood to carry ...

  11. When Blood Cells Bend: Understanding Sickle Cell Disease

    Science.gov (United States)

    ... please review our exit disclaimer . Subscribe When Blood Cells Bend Understanding Sickle Cell Disease For people who don’t suspect they ... Cells Bend Wise Choices Links Living with Sickle Cell Disease See a sickle cell disease expert regularly. ...

  12. 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.

  13. Cell fusion of bone marrow cells and somatic cell reprogramming by embryonic stem cells

    OpenAIRE

    Bonde, Sabrina; Pedram, Mehrdad; Stultz, Ryan; Zavazava, Nicholas

    2010-01-01

    Bone marrow transplantation is a curative treatment for many diseases, including leukemia, autoimmune diseases, and a number of immunodeficiencies. Recently, it was claimed that bone marrow cells transdifferentiate, a much desired property as bone marrow cells are abundant and therefore could be used in regenerative medicine to treat incurable chronic diseases. Using a Cre/loxP system, we studied cell fusion after bone marrow transplantation. Fused cells were chiefly Gr-1+, a myeloid cell mar...

  14. Hepatic stem cell niches

    OpenAIRE

    Kordes, Claus; Häussinger, Dieter

    2013-01-01

    Stem cell niches are special microenvironments that maintain stem cells and control their behavior to ensure tissue homeostasis and regeneration throughout life. The liver has a high regenerative capacity that involves stem/progenitor cells when the proliferation of hepatocytes is impaired. In recent years progress has been made in the identification of potential hepatic stem cell niches. There is evidence that hepatic progenitor cells can originate from niches in the canals...

  15. Stem Cell Networks

    OpenAIRE

    Werner, Eric

    2016-01-01

    We present a general computational theory of stem cell networks and their developmental dynamics. Stem cell networks are special cases of developmental control networks. Our theory generates a natural classification of all possible stem cell networks based on their network architecture. Each stem cell network has a unique topology and semantics and developmental dynamics that result in distinct phenotypes. We show that the ideal growth dynamics of multicellular systems generated by stem cell ...

  16. Stem cell mechanobiology

    OpenAIRE

    David A. Lee; Knight, Martin M.; Jonathan J Campbell; Bader, Dan L.

    2010-01-01

    Stem cells are undifferentiated cells that are capable of proliferation, self-maintenance and differentiation towards specific cell phenotypes. These processes are controlled by a variety of cues including physicochemical factors associated with the specific mechanical environment in which the cells reside. The control of stem cell biology through mechanical factors remains poorly understood and is the focus of the developing field of mechanobiology. This review provides an insight into the c...

  17. Embryonic Stem Cell Markers

    OpenAIRE

    Lan Ma; Liang Li; Wenxiu Zhao; Xiang Ji; Fangfang Zhang

    2012-01-01

    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 type...

  18. Limbal stem cell transplantation

    OpenAIRE

    Fernandes Merle; Sangwan Virender; Rao Srinivas; Basti Surendra; Sridhar Mittanamalli; Bansal Aashish; Dua Harminder

    2004-01-01

    The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This ...

  19. Intraoperative Stem Cell Therapy

    OpenAIRE

    Coelho, Mónica Beato; Cabral, Joaquim M. S.; Karp, Jeffrey M.

    2012-01-01

    Stem cells hold significant promise for regeneration of tissue defects and disease-modifying therapies. Although numerous promising stem cell approaches are advancing in clinical trials, intraoperative stem cell therapies offer more immediate hope by integrating an autologous cell source with a well-established surgical intervention in a single procedure. Herein, the major developments in intraoperative stem cell approaches, from in vivo models to clinical studies, are reviewed, and the poten...

  20. The leukemic stem cell

    OpenAIRE

    Jordan, Craig T.

    2007-01-01

    Malignant stem cells have recently been described as the source of several types of human cancer. These unique cell types are typically rare and possess properties that are distinct from most other tumor cells. The properties of leukemic stem cells indicate that current chemotherapy drugs will not be effective. The use of current cytotoxic agents is not effective in leukemia because the agents target both the leukemic and normal stem cell populations. Consequently, new strategies are required...

  1. Cancer Stem Cells

    OpenAIRE

    Katarzyna Wieczorek; Jolanta Niewiarowska

    2008-01-01

    Cancer stem cell theory gains increasingly greater significance in the world of medicine. Numerous findings of scientific research in vivo and in vitro indicate that it is the population of undifferentiated, self-renewing cells which is responsible for recurrence of cancer and metastasis. Similarly to normal stem cells, cancer stem cells (CSC) function in the environment of the other cells of the organism, called the niche, where they receive signals for differentiation and proliferation proc...

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

    OpenAIRE

    El-Badawy, Ahmed; El-Badri, Nagwa

    2016-01-01

    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 ...

  3. Mechanically facilitated cell-cell electrofusion.

    OpenAIRE

    Jaroszeski, M. J.; Gilbert, R.; Fallon, P.G.; Heller, R

    1994-01-01

    Apparatus and methods were developed to enable mechanically facilitated cell-cell electrofusion to be performed. The apparatus and methods mechanically place cells in contact before fusion. The key component of this fusion system was a newly developed fusion chamber. The chamber was composed of two functionally identical electrodes that were housed in a multi-layer structure. The layers functioned as support for the electrodes. They also allowed adjustment of the distance between opposing ele...

  4. Optimizing stem cell culture.

    Science.gov (United States)

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-11-01

    Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such as serum or feeder cell layers by recombinant cytokines or growth factors. Another example is the control of the oxygen pressure. For many years cell cultures have been done under atmospheric oxygen pressure which is much higher than the one experienced by stem cells in vivo. A consequence of cell metabolism is that cell culture conditions are constantly changing. Therefore, the development of high sensitive monitoring processes and control algorithms is required for ensuring cell culture medium homeostasis. Stem cells also sense the physical constraints of their microenvironment. Rigidity, stiffness, and geometry of the culture substrate influence stem cell fate. Hence, nanotopography is probably as important as medium formulation in the optimization of stem cell culture conditions. Recent advances include the development of synthetic bioinformative substrates designed at the micro- and nanoscale level. On going research in many different fields including stem cell biology, nanotechnology, and bioengineering suggest that our current way to culture cells in Petri dish or flasks will soon be outdated as flying across the Atlantic Ocean in the Lindbergh's plane. PMID:20803548

  5. Living with Sickle Cell Disease

    Science.gov (United States)

    ... sickle cell disease, go to the Health Topics Sickle Cell Anemia article. Living With and Managing Sickle Cell Disease ( ... the most severe form of sickle cell disease, sickle cell anemia, Tiffany has lived with the symptoms and complications ...

  6. What Causes Sickle Cell Disease?

    Science.gov (United States)

    ... sickle cell disease, go to the Health Topics Sickle Cell Anemia article. Living With and Managing Sickle Cell Disease ( ... the most severe form of sickle cell disease, sickle cell anemia, Tiffany has lived with the symptoms and complications ...

  7. 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.

  8. 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

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. Assessment of pancreas cells

    Science.gov (United States)

    Vanoss, C. J.

    1978-01-01

    Pancreatic islets were obtained from guinea pig pancreas by the collagenase method and kept alive in tissue culture prior to further studies. Pancreas cell morphology was studied by standard histochemical techniques using light microscopy. Preparative vertical electrophoresis-levitation of dispersed fetal guinea pig pancreas cells was conducted in phosphate buffer containing a heavy water (D20) gradient which does not cause clumping of cells or alter the osmolarity of the buffers. The faster migrating fractions tended to be enriched in beta-cell content. Alpha and delta cells were found to some degree in most fractions. A histogram showing the cell count distribution is included.

  14. Resident Peritoneal NK cells

    OpenAIRE

    Gonzaga, Rosemary; Matzinger, Polly; Perez-Diez, Ainhoa

    2011-01-01

    Here we describe a new population of NK cells that reside in the normal, un-inflamed peritoneal cavity. Phenotypically, they share some similarities with the small population of CD49b negative, CD27 positive immature splenic NK cells, and liver NK cells but differ in their expression of CD62L, TRAIL and EOMES. Functionally, the peritoneal NK cells resemble the immature splenic NK cells in their production of IFN-γ, GM-CSF and TNF-α and in the killing of YAC-1 target cells. We also found that ...

  15. Multipotent adult progenitor cell and stem cell plasticity

    OpenAIRE

    Jahagirdar, Balkrishna N; Verfaillie, Catherine

    2005-01-01

    Stem cells are defined by their biological function. A stem cell is an undifferentiated cell that self-renews to maintain the stem cell pool and at the single-cell level differentiates into more than one mature, functional cell. In addition, when transplanted, a stem cell should be capable of replacing a damaged organ or tissue for the lifetime of the recipient. Some would argue that stem cells should also be capable of functionally integrating into nondamaged tissues. Stem cells are critical...

  16. Epidermal Stem Cells

    Directory of Open Access Journals (Sweden)

    Osman Köse

    2015-03-01

    Full Text Available The epidermis is the outermost layer of the human skin and comprises a multilayered epithelium, the interfollicular epidermis, with associated hair follicles, sebaceous glands, and eccrine sweat glands. There are many origins of stem cells in the skin and skin appendages. These stem cells are localized in different part of the pilosebaseous units and also express many different genes. Epidermal stem cells in the pilosebaseous units not only ensure the maintenance of epidermal homeostasis and hair regeneration, but also contribute to repair of the epidermis after injury. In recent years, human induced pluripotent skin stem cells are produced from the epidermal cells such as keratinocytes, fibroblasts and melanocytes. These cells can be transdifferentiated to embriyonic stem cells. Human induced pluripotent stem cells have potential applications in cell replacement therapy and regenerative medicine. These cells provide a means to create valuable tools for basic research and may also produce a source of patient-matched cells for regenerative therapies. In this review, we aimed an overview of epidermal stem cells for better understanding their functions in the skin. Skin will be main organ for using the epidermal cells for regenerative medicine in near future.

  17. 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.

  18. 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.

  19. Toward 'SMART' stem cells.

    Science.gov (United States)

    Cheng, T

    2008-01-01

    Stem cell research is at the heart of regenerative medicine, which holds great promise for the treatment of many devastating disorders. However, in addition to hurdles posed by well-publicized ethical issues, this emerging field presents many biological challenges. What is a stem cell? How are embryonic stem cells different from adult stem cells? What are the physiological bases for therapeutically acceptable stem cells? In this editorial review, I will briefly discuss these superficially simple but actually rather complex issues that surround this fascinating cell type. The goal of this special issue on stem cells in Gene Therapy is to review some fundamental and critical aspects of current stem cell research that have translational potential. PMID:18046429

  20. 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.

  1. 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 ...

  2. 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.

  3. Sickle Cell Trait

    Science.gov (United States)

    ... About Us Information For... Media Policy Makers Sickle Cell Trait Language: English Español (Spanish) Recommend on Facebook ... the trait on to their children. How Sickle Cell Trait is Inherited If both parents have SCT, ...

  4. Sickle Cell Disease Quiz

    Science.gov (United States)

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

  5. Mammalian cell biology

    International Nuclear Information System (INIS)

    This section contains summaries of research on mechanisms of lethality and radioinduced changes in mammalian cell properties, new cell systems for the study of the biology of mutation and neoplastic transformation, and comparative properties of ionizing radiations

  6. Anaplastic Large Cell Lymphoma

    Science.gov (United States)

    Anaplastic Large Cell Lymphoma Overview Lymphoma is the most common blood cancer. The two main forms of lymphoma are ... organs, and can accumulate to form tumors. Anaplastic large cell lymphoma (ALCL) is arare type of NHL, ...

  7. What Are Islet Cells?

    Science.gov (United States)

    ... Video Be Part of the Cure Commitment to Stem Cell Research Exercise + Drug Therapy Tibi Creates Garment to Benefit ... Video Be Part of the Cure Commitment to Stem Cell Research Exercise + Drug Therapy Tibi Creates Garment to Benefit ...

  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. Sickle cell anemia

    Science.gov (United States)

    ... for avascular necrosis of the hip Surgery for eye problems Treatment for overuse or abuse of narcotic pain medicines Wound care for leg ulcers Bone marrow or stem cell transplants can cure sickle cell anemia, but this treatment ...

  10. 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.

  11. 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.

  12. 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.

  13. 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....

  14. Nanoelectrochemistry of mammalian cells

    OpenAIRE

    Sun, Peng; Laforge, François O.; Abeyweera, Thushara P.; Rotenberg, Susan A.; Carpino, James; Mirkin, Michael V.

    2008-01-01

    There is a significant current interest in development of new techniques for direct characterization of the intracellular redox state and high-resolution imaging of living cells. We used nanometer-sized amperometric probes in combination with the scanning electrochemical microscope (SECM) to carry out spatially resolved electrochemical experiments in cultured human breast cells. With the tip radius ≈1,000 times smaller than that of a cell, an electrochemical probe can penetrate a cell and tra...

  15. Optimizing stem cell culture.

    OpenAIRE

    van der Sanden, Boudewijn; Dhobb, Mehdi; Berger, François; Wion, Didier

    2010-01-01

    International audience Stem cells always balance between self-renewal and differentiation. Hence, stem cell culture parameters are critical and need to be continuously refined according to progress in our stem cell biology understanding and the latest technological developments. In the past few years, major efforts have been made to define more precisely the medium composition in which stem cells grow or differentiate. This led to the progressive replacement of ill-defined additives such a...

  16. 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.

  17. Prostate cancer stem cells

    OpenAIRE

    Tu, Shi-Ming; Lin, Sue-Hwa

    2011-01-01

    Stem cells have long been implicated in prostate glandular formation. The prostate undergoes regression after androgen deprivation and regeneration after testosterone replacement. Regenerative studies suggest that these cells are found in the proximal ducts and basal layer of the prostate. Many characteristics of prostate cancer indicate that it originates from stem cells. For example, the putative AR− status of prostate stem cells renders them inherently insensitive to androgen blockade ther...

  18. Lung Cancer Stem Cells

    OpenAIRE

    Pine, Sharon R.; Blair Marshall; Lyuba Varticovski

    2008-01-01

    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 p...

  19. 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.

  20. Aneuploidy in stem cells

    OpenAIRE

    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 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 bluepri...

  1. Antitumor Immunity Produced by the Liver Kupffer Cells, NK Cells, NKT Cells, and CD8+ CD122+ T Cells

    OpenAIRE

    Shuhji Seki; Hiroyuki Nakashima; Masahiro Nakashima; Manabu Kinoshita

    2011-01-01

    Mouse and human livers contain innate immune leukocytes, NK cells, NKT cells, and macrophage-lineage Kupffer cells. Various bacterial components, including Toll-like receptor (TLR) ligands and an NKT cell ligand ( α -galactocylceramide), activate liver Kupffer cells, which produce IL-1, IL-6, IL-12, and TNF. IL-12 activates hepatic NK cells and NKT cells to produce IFN- γ , which further activates hepatic T cells, in turn activating phagocytosis and cytokine production by Kupffer cells in a p...

  2. Biomechanical assays amniotic membrane preserved in glycerol correlating with optical coherence tomography (OCT) and thermal gravimetric analysis (TG)

    Energy Technology Data Exchange (ETDEWEB)

    Soares, Fernando Augusto N.; Santin, Stefany P.; Martino Junior, Antonio C.; Machado, Luci Diva B.; Freitas, Anderson Z.; Mathor, Monica B., E-mail: fernandonevessoares@yahoo.com.br [Instituto de Pesquisas Energetias Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-07-01

    Amnion or amniotic membranes (AM) are interchangeable terms used in the literature being internal part of the fetal membranes, non-vascular and multicellular tissue. The amnion has been widely used as a graft ophthalmic surgical as well as carrier substrate stem cell tissue equivalent for ocular surface reconstruction. The AM reduces scar formation and inflammation on the ocular surface, promotes epithelization also been used as a biological bandage covering the wound or burns, reducing dehydration and allowing regeneration of these areas. The amnion has usually 0.02 to 0.5 mm thick and consists of five subsequent layers: epithelium, basement membrane, compact layer, fibroblast layer and spongy layer. The mechanical strength from the membrane structure as well as the elasticity are factors attractive to the use of amnion as a surgical graft. Higher levels of rigidity and strength may improve the graft resistance necessary to resist the stress induced during growth of the new tissue formed. The amniotic membrane is obtained at elective caesarean section and subsequently, under sterile conditions, sectioned and separated from chorion and placenta, and free blood clots. The serological tests are done at the time of collection of tissue and 6 months after delivery to confirm the results. There are different methods for storing MA in tissue banks as fresh, high concentrations of glycerol, among others. The use of fresh membrane has some limitations due to the need to rapid use and high risk of contamination, however the amniotic membrane in glycerol has antiviral and antibacterial property which is dependent on the concentration, time and temperature. The AM used in transplants must be sterile to prevent the transmission of any disease. Although sterilization by radiation is an effective procedure, it can interfere on the membrane structure. Thus, verification of potential changes caused by ionizing radiation in amnion was made using the tensile test by calculating the

  3. 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....

  4. 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....

  5. 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

  6. 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 ...

  7. 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.

  8. 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…

  9. 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

  10. 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.

  11. astrocyte and astrocytoma cells

    DEFF Research Database (Denmark)

    Tfelt-Hansen, J.

    2008-01-01

    -transforming gene (PTTG), was found to be upregulated by the CaR in the H-500 cells, whereas calcium had no effect on PTTG expression in the U-87 astrocytoma cell line, but other proproliferative agents did upregulate PTTG in the U-87 cells. This makes PTTG a potential marker of malignancy and a therapeutic target...

  12. Advanced Cell Technology, Inc.

    Science.gov (United States)

    Caldwell, William M

    2007-03-01

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

  13. 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.

  14. 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…

  15. STEM CELLS: Differentiated cells in a back-up role

    OpenAIRE

    Desai, Tushar J.; Krasnow, Mark A.

    2013-01-01

    Two independent studies show that, if push comes to shove, differentiated cells of the stomach and lung can act as adult stem cells generating various cell types of the tissue, including a pool of stem cells.

  16. MAPK uncouples cell cycle progression from cell spreading and cytoskeletal organization in cycling cells

    OpenAIRE

    Margadant, Coert; Cremers, Lobke; Sonnenberg, Arnoud; Boonstra, Johannes

    2012-01-01

    Integrin-mediated cytoskeletal tension supports growth-factor-induced proliferation, and disruption of the actin cytoskeleton in growth factor-stimulated cells prevents the re-expression of cyclin D and cell cycle re-entry from quiescence. In contrast to cells that enter the cell cycle from G0, cycling cells continuously express cyclin D, and are subject to major cell shape changes during the cell cycle. Here, we investigated the cell cycle requirements for cytoskeletal tension and cell sprea...

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

    OpenAIRE

    Quanwen Liu; Yi Shen; Jiarong Chen; Jie Ding; Zihua Tang; Cui Zhang; Jianling Chen; Liang Li; Ping Chen; Jinfu Wang

    2016-01-01

    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 bund...

  18. 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....

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. Parameterization of solar cells

    Science.gov (United States)

    Appelbaum, J.; Chait, A.; Thompson, D.

    1992-10-01

    The aggregation (sorting) of the individual solar cells into an array is commonly based on a single operating point on the current-voltage (I-V) characteristic curve. An alternative approach for cell performance prediction and cell screening is provided by modeling the cell using an equivalent electrical circuit, in which the parameters involved are related to the physical phenomena in the device. These analytical models may be represented by a double exponential I-V characteristic with seven parameters, by a double exponential model with five parameters, or by a single exponential equation with four or five parameters. In this article we address issues concerning methodologies for the determination of solar cell parameters based on measured data points of the I-V characteristic, and introduce a procedure for screening of solar cells for arrays. We show that common curve fitting techniques, e.g., least squares, may produce many combinations of parameter values while maintaining a good fit between the fitted and measured I-V characteristics of the cell. Therefore, techniques relying on curve fitting criteria alone cannot be directly used for cell parameterization. We propose a consistent procedure which takes into account the entire set of parameter values for a batch of cells. This procedure is based on a definition of a mean cell representing the batch, and takes into account the relative contribution of each parameter to the overall goodness of fit. The procedure is demonstrated on a batch of 50 silicon cells for Space Station Freedom.

  4. T cell subpopulations.

    Science.gov (United States)

    Romagnani, Sergio

    2014-01-01

    The role of allergen-specific CD4+ effector type 2 helper (Th2) cells in the pathogenesis of allergic disorders is an established fact. Th2 cells produce interleukin (IL)-4 and IL-13, which induce immunoglobulin E production by B cells, and IL-5 that allows recruitment of eosinophils. Two main mechanisms control the Th2-mediated allergic inflammation: immune deviation (or Th1 redirection) and immune regulation. Regulatory T (Treg) cells exhibit a CD4+ phenotype and include Foxp3-positive thymic and induced Tregs, as well as Foxp3-negative IL-10-producing cells. Both immune deviation and immune regulation evoked by the maternal and newborn microbial environment probably operate in preventing allergen-specific Th2 responses. However, microbe-related protection from allergy seems to mainly depend on epigenetically controlled acetylation of the IFNG promoter of CD4+ T cells. Even Th17 and Th9 cells, as well as invariant NKT cells, have been implicated in the pathogenesis of allergic disorders, but their role is certainly more limited. Recently, innate lymphoid type 2 cells (ILC2) have been found to be able to produce high amounts of IL-5 and IL-13 in response to stimulation with IL-25 and IL-33 produced by non-immune cells. Together with Th2 cells, ILC2 may contribute to the induction and maintenance of allergic inflammation. PMID:24925396

  5. Cell adhesion in regulation of asymmetric stem cell division

    OpenAIRE

    Yamashita, Yukiko M

    2010-01-01

    Adult stem cells inevitably communicate with their cellular neighbors within the tissues they sustain. Indeed, such communication, particularly with components of the stem cell niche, is essential for many aspects of stem cell behavior, including the maintenance of stem cell identity and asymmetric cell division. Cell adhesion mediates this communication by placing stem cells in close proximity to the signaling source and by providing a polarity cue that orients stem cells. Here, I review the...

  6. 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.

  7. 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....

  8. 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...

  9. 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 ...

  10. 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.

  11. T Cells Going Innate.

    Science.gov (United States)

    Seyda, Midas; Elkhal, Abdallah; Quante, Markus; Falk, Christine S; Tullius, Stefan G

    2016-08-01

    Natural killer (NK) cell receptors (NKRs) play a crucial role in the homeostasis of antigen-experienced T cells. Indeed, prolonged antigen stimulation may induce changes in the receptor repertoire of T cells to a profile that features NKRs. Chronic antigen exposure, at the same time, has been shown to trigger the loss of costimulatory CD28 molecules with recently reported intensified antigen thresholds of antigen-experienced CD8(+) T cells. In transplantation, NKRs have been shown to assist allograft rejection in a CD28-independent fashion. We discuss here a role for CD28-negative T cells that have acquired the competency of the NKR machinery, potentially promoting allorecognition either through T cell receptor (TCR) crossreactivity or independently from TCR recognition. Collectively, NKRs can bring about innate-like T cells by providing alternative costimulatory pathways that gain relevance in chronic inflammation, potentially leading to resistance to CD28-targeting immunosuppressants. PMID:27402226

  12. Information on Stem Cell Research

    Science.gov (United States)

    ... Enhancing Diversity Find People About NINDS Information on Stem Cell Research Research @ NINDS Stem Cell Highlights Submit a hESC ... found here: Human Induced Pluripotent Stem Cells NINDS Stem Cell Research on Campus The Intramural Research Program of NINDS ...

  13. Nevoid Basal Cell Carcinoma Syndrome

    Science.gov (United States)

    ... Nevoid Basal Cell Carcinoma Syndrome Request Permissions Nevoid Basal Cell Carcinoma Syndrome Approved by the Cancer.Net Editorial Board , 04/2016 What is Nevoid Basal Cell Carcinoma Syndrome? Nevoid Basal Cell Carcinoma Syndrome (NBCCS) is ...

  14. Nestin(+) cells direct inflammatory cell migration in atherosclerosis.

    Science.gov (United States)

    Del Toro, Raquel; Chèvre, Raphael; Rodríguez, Cristina; Ordóñez, Antonio; Martínez-González, José; Andrés, Vicente; Méndez-Ferrer, Simón

    2016-01-01

    Atherosclerosis is a leading death cause. Endothelial and smooth muscle cells participate in atherogenesis, but it is unclear whether other mesenchymal cells contribute to this process. Bone marrow (BM) nestin(+) cells cooperate with endothelial cells in directing monocyte egress to bloodstream in response to infections. However, it remains unknown whether nestin(+) cells regulate inflammatory cells in chronic inflammatory diseases, such as atherosclerosis. Here, we show that nestin(+) cells direct inflammatory cell migration during chronic inflammation. In Apolipoprotein E (ApoE) knockout mice fed with high-fat diet, BM nestin(+) cells regulate the egress of inflammatory monocytes and neutrophils. In the aorta, nestin(+) stromal cells increase ∼30 times and contribute to the atheroma plaque. Mcp1 deletion in nestin(+) cells-but not in endothelial cells only- increases circulating inflammatory cells, but decreases their aortic infiltration, delaying atheroma plaque formation and aortic valve calcification. Therefore, nestin expression marks cells that regulate inflammatory cell migration during atherosclerosis. PMID:27586429

  15. 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...

  16. Introduction to Stem Cell Therapy

    OpenAIRE

    Biehl, Jesse K.; Russell, Brenda

    2009-01-01

    Stem cells have the ability to differentiate into specific cell types. The two defining characteristics of a stem cell are perpetual self-renewal and the ability to differentiate into a specialized adult cell type. There are two major classes of stem cells: pluripotent that can become any cell in the adult body, and multipotent that are restricted to becoming a more limited population of cells. Cell sources, characteristics, differentiation and therapeutic applications are discussed. Stem cel...

  17. Simple Cell Balance Circuit

    Science.gov (United States)

    Johnson, Steven D.; Byers, Jerry W.; Martin, James A.

    2012-01-01

    A method has been developed for continuous cell voltage balancing for rechargeable batteries (e.g. lithium ion batteries). A resistor divider chain is provided that generates a set of voltages representing the ideal cell voltage (the voltage of each cell should be as if the cells were perfectly balanced). An operational amplifier circuit with an added current buffer stage generates the ideal voltage with a very high degree of accuracy, using the concept of negative feedback. The ideal voltages are each connected to the corresponding cell through a current- limiting resistance. Over time, having the cell connected to the ideal voltage provides a balancing current that moves the cell voltage very close to that ideal level. In effect, it adjusts the current of each cell during charging, discharging, and standby periods to force the cell voltages to be equal to the ideal voltages generated by the resistor divider. The device also includes solid-state switches that disconnect the circuit from the battery so that it will not discharge the battery during storage. This solution requires relatively few parts and is, therefore, of lower cost and of increased reliability due to the fewer failure modes. Additionally, this design uses very little power. A preliminary model predicts a power usage of 0.18 W for an 8-cell battery. This approach is applicable to a wide range of battery capacities and voltages.

  18. B cells help alloreactive T cells differentiate into memory T cells1

    OpenAIRE

    Ng, Yue-Harn; Oberbarnscheidt, Martin H.; Chandramoorthy, Harish Chinna Konda; Hoffman, Rosemary; Chalasani, Geetha

    2010-01-01

    B cells are recognized as effector cells in allograft rejection that are dependent upon T cell help to produce alloantibodies causing graft injury. It is not known if B cells can also help T cells differentiate into memory cells in the alloimmune response. We found that in B cell-deficient hosts, differentiation of alloreactive T cells into effectors was intact whereas their development into memory T cells was impaired. To test if B cell help for T cells was required for their continued diffe...

  19. Expression of immunoreactive urocortin in human tissue

    Institute of Scientific and Technical Information of China (English)

    GU Qing; Vicki L Clifton; CUI Ying; HUI Ning; ZHOU Xiao-ning; HE Qian; HAN Qing-feng; SHA Jin-yan; Roger Smith

    2001-01-01

    To localize where urocortin is expressed in human tissue in an attempt to study its physiological functions. Methods: Expression of immunoreactive urocortin in different human tissue was examined using a specific urocortin antibody and the immunoperoxidase staining method. Results: Immunoreactive urocortin was observed in the anterior pituitary cells, decidual stromal cells, syncytiotrophoblasts, amnion epithelium, the vascular smooth muscles of myometrium, fallopian tube and small intestine. Conclusion: The study indicates that urocortin is expressed in some specific areas of human tissue. The data are consistent with the hypothesis that urocortin is produced locally as an endocrine factor, which may act as a neural regulator and a regulator of local blood flow.

  20. 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.

  1. 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...

  2. 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.

  3. 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...

  4. 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.

  5. Mammalian cell biology

    International Nuclear Information System (INIS)

    Studies of the action of N-ethylmaleimide (NEM), as an inhibitor of repair of x radioinduced injuries were extended from synchronous Chinese hamster cells to synchronous human HeLa cells. These studies showed a similar mode of action in both cell types lending support to the notion that conclusions may be extracted from such observations that are of fairly general applicability to mammalian cells. Radiation studies with NEM are being extended to hypoxic cells to inquire if NEM is effective relative to oxygen-independent damage. Observations relative to survival, DNA synthesis, and DNA strand elongation resulting from the addition products to DNA when cells were exposed to near uv in the presence of psoralen were extended. (U.S.)

  6. 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.

  7. Basal cell carcinoma of the skin with areas of squamous cell carcinoma: a basosquamous cell carcinoma?

    OpenAIRE

    Faria, J.

    1985-01-01

    The diagnosis of basosquamous cell carcinoma is controversial. A review of cases of basal cell carcinoma showed 23 cases that had conspicuous areas of squamous cell carcinoma. This was distinguished from squamous differentiation and keratotic basal cell carcinoma by a comparative study of 40 cases of compact lobular and 40 cases of keratotic basal cell carcinoma. Areas of intermediate tumour differentiation between basal cell and squamous cell carcinoma were found. Basal cell carcinomas with ...

  8. Traction in smooth muscle cells varies with cell spreading

    Science.gov (United States)

    Tolic-Norrelykke, Iva Marija; Wang, Ning

    2005-01-01

    Changes in cell shape regulate cell growth, differentiation, and apoptosis. It has been suggested that the regulation of cell function by the cell shape is a result of the tension in the cytoskeleton and the distortion of the cell. Here we explore the association between cell-generated mechanical forces and the cell morphology. We hypothesized that the cell contractile force is associated with the degree of cell spreading, in particular with the cell length. We measured traction fields of single human airway smooth muscle cells plated on a polyacrylamide gel, in which fluorescent microbeads were embedded to serve as markers of gel deformation. The traction exerted by the cells at the cell-substrate interface was determined from the measured deformation of the gel. The traction was measured before and after treatment with the contractile agonist histamine, or the relaxing agonist isoproterenol. The relative increase in traction induced by histamine was negatively correlated with the baseline traction. On the contrary, the relative decrease in traction due to isoproterenol was independent of the baseline traction, but it was associated with cell shape: traction decreased more in elongated than in round cells. Maximum cell width, mean cell width, and projected area of the cell were the parameters most tightly coupled to both baseline and histamine-induced traction in this study. Wide and well-spread cells exerted larger traction than slim cells. These results suggest that cell contractility is controlled by cell spreading.

  9. Microbial fuel cells

    International Nuclear Information System (INIS)

    Microbial fuel cells (MFC) are a promising technology for sustainable production of alternative energy and waste treatment. A microbial fuel cell transformation chemical energy in the chemical bonds in organic compounds to electrical energy through catalytic reactions of microorganisms under anaerobic conditions. It has been known for many years that it is possible to generate electricity directly by using bacteria to break down organic substrates. Key words: microbial fuel cells (MFC), biosensor, wastewater treatment

  10. Epidermal Stem Cells

    OpenAIRE

    Osman Köse

    2015-01-01

    The epidermis is the outermost layer of the human skin and comprises a multilayered epithelium, the interfollicular epidermis, with associated hair follicles, sebaceous glands, and eccrine sweat glands. There are many origins of stem cells in the skin and skin appendages. These stem cells are localized in different part of the pilosebaseous units and also express many different genes. Epidermal stem cells in the pilosebaseous units not only ensure the maintenance of epidermal homeostasis and ...

  11. Liver Cancer Stem Cells

    OpenAIRE

    Sameh Mikhail; Aiwu Ruth He

    2011-01-01

    Hepatocellular carcinoma is the most common primary malignancy of the liver in adults. It is also the fifth most common solid cancer worldwide and the third leading cause of cancer-related death. Recent research supports that liver cancer is a disease of adult stem cells. From the models of experimental hepatocarcinogenesis, there may be at least three distinct cell lineages with progenitor properties susceptible to neoplastic transformation. Identification of specific cell surface markers fo...

  12. 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.

  13. Cell therapy of pseudarthrosis

    OpenAIRE

    Bastos Filho, Ricardo; Lermontov, Simone; Borojevic, Radovan; Schott, Paulo Cezar; Gameiro, Vinicius Schott; José Mauro GRANJEIRO

    2012-01-01

    Objective To assess the safety and efficiency of cell therapy for pseudarthrosis. Implant of the bone marrow aspirate was compared to mononuclear cells purified extemporaneously using the Sepax® equipment. Methods Six patients with nonunion of the tibia or femur were treated. Four received a percutaneous infusion of autologous bone marrow aspirated from the iliac crest, and two received autologous bone marrow mononuclear cells separated from the aspirate with the Sepax®. The primary fixation ...

  14. Chiaroscuro hematopoietic stem cell.

    OpenAIRE

    Quesenberry, P.; Habibian, M. (PhD); Dooner, M; Zhong, S.; Reilly, J; Peters, S.; De Becker, P; Grimaldi, C.; Carlson, J; REDDY, P; Nilsson, S.; Stewart, F. M.

    1998-01-01

    These observations suggest several immediate clinical strategies. In gene therapy, approaches could be targeted to obtain cycling of hematopoietic stem cells and gene-carrying retrovirus vector integration followed by engraftment at an appropriate time interval which favors engraftment. The same type of approach can be utilized for stem cell expansion approaches. Alternatively marrow or peripheral stem cell engraftment can be obtained with minimal to no toxicity in allochimeric strategies in ...

  15. Stem cell myths

    OpenAIRE

    Magnus, Tim; Liu, Ying; Parker, Graham C.; Rao, Mahendra S.

    2007-01-01

    Stem cells, although difficult to define, hold great promise as tools for understanding development and as therapeutic agents. However, as with any new field, uncritical enthusiasm can outstrip reality. In this review, we have listed nine common myths that we believe affect our approach to evaluating stem cells for therapy. We suggest that careful consideration needs to be given to each of these issues when evaluating a particular cell for its use in therapy. Data need to be collected and rep...

  16. Cancer stem cell metabolism

    OpenAIRE

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

    2016-01-01

    Cancer is now viewed as a stem cell disease. There is still no consensus on the metabolic characteristics of cancer stem cells, with several studies indicating that they are mainly glycolytic and others pointing instead to mitochondrial metabolism as their principal source of energy. 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. Deter...

  17. Lung Stem cell biology

    OpenAIRE

    Ardhanareeswaran, Karthikeyan; Mirotsou, Maria

    2013-01-01

    Over the past few years new insights have been added to the study of stem cells in the adult lung. The exploration of the endogenous lung progenitors as well as the study of exogenously delivered stem cell populations holds promise for advancing our understanding of the biology of lung repair mechanisms. Moreover, it opens new possibilities for the use of stem cell therapy for the development of regenerative medicine approaches for the treatment of lung disease. Here, we discuss the main type...

  18. Gastric Cancer Stem Cells

    OpenAIRE

    Takaishi, Shigeo; Okumura, Tomoyuki; Timothy C Wang

    2008-01-01

    Cancer stem cells are defined as the unique subpopulation in the tumors that possess the ability to initiate tumor growth and sustain self-renewal as well as metastatic potential. Accumulating evidence in recent years strongly indicate the existence of cancer stem cells in solid tumors of a wide variety of organs. In this review, we will discuss the possible existence of a gastric cancer stem cell. Our recent data suggest that a subpopulation with a defined marker shows spheroid colony format...

  19. APUD cells in teratomas.

    OpenAIRE

    Bosman, F. T.; Louwerens, J. W.

    1981-01-01

    The origin of the endocrine cells in the respiratory tract and the gastrointestinal tract is still a matter of debate. In the original concept of the amine precursor uptake and decarboxylation (APUD) system, all APUD cells were considered to be derived from the neural crest. More recently it has been proposed that the APUD cell types of the gastrointestinal and respiratory tracts originate from neuroendocrine-programmed ectoblast. Still other investigators have reported observations that favo...

  20. Hair cell ribbon synapses

    OpenAIRE

    Moser, Tobias; Brandt, Andreas; Lysakowski, Anna

    2006-01-01

    Hearing and balance rely on the faithful synaptic coding of mechanical input by the auditory and vestibular hair cells of the inner ear. Mechanical deflection of their stereocilia causes the opening of mechanosensitive channels, resulting in hair cell depolarization, which controls the release of glutamate at ribbon-type synapses. Hair cells have a compact shape with strong polarity. Mechanoelectrical transduction and active membrane turnover associated with stereociliar renewal dominate the ...

  1. 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.

  2. Nanocrystal Solar Cells

    Energy Technology Data Exchange (ETDEWEB)

    Gur, Ilan

    2006-12-15

    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.

  3. Mesenchymal stem cells.

    Science.gov (United States)

    Ding, Dah-Ching; Shyu, Woei-Cherng; Lin, Shinn-Zong

    2011-01-01

    Stem cells have two features: the ability to differentiate along different lineages and the ability of self-renewal. Two major types of stem cells have been described, namely, embryonic stem cells and adult stem cells. Embryonic stem cells (ESC) are obtained from the inner cell mass of the blastocyst and are associated with tumorigenesis, and the use of human ESCs involves ethical and legal considerations. The use of adult mesenchymal stem cells is less problematic with regard to these issues. Mesenchymal stem cells (MSCs) are stromal cells that have the ability to self-renew and also exhibit multilineage differentiation. MSCs can be isolated from a variety of tissues, such as umbilical cord, endometrial polyps, menses blood, bone marrow, adipose tissue, etc. This is because the ease of harvest and quantity obtained make these sources most practical for experimental and possible clinical applications. Recently, MSCs have been found in new sources, such as menstrual blood and endometrium. There are likely more sources of MSCs waiting to be discovered, and MSCs may be a good candidate for future experimental or clinical applications. One of the major challenges is to elucidate the mechanisms of differentiation, mobilization, and homing of MSCs, which are highly complex. The multipotent properties of MSCs make them an attractive choice for possible development of clinical applications. Future studies should explore the role of MSCs in differentiation, transplantation, and immune response in various diseases. PMID:21396235

  4. Red cell enzymes.

    Science.gov (United States)

    Paniker, N V

    1975-03-01

    As compared to other cells of the body, the mammalian red cell has one of the simplest structural organizations. As a result, this cell has been extensively used in studies involving the structure, function, and integrity of cell membranes as well as cytoplasmic events. Additionally, the metabolic activities of the red blood cell are also relatively simple. During the past quarter century or so, an ocean of knowledge has been gathered on various aspects of red cell metabolism and function. The fields of enzymes, hemoglobin, membrane, and metabolic products comprise the major portion of this knowledge. These advances have made valuable contributions to biochemistry and medicine. Despite these favorable aspects of this simple, anucleated cell, it must be conceded that our knowledge about the red cell is far from complete. We are still in the dark concerning the mechanism involved in several aspects of its membrane, hemoglobin, enzymes, and a large number of other constituents. For example, a large number of enzymes with known catalytic activity but with unknown function have eluded investigators despite active pursuit. This review will be a consolidation of our present knowledge of human red cell enzymes, with particular reference to their usefulness in the diagnosis and therapy of disease. Owing to the multitude of publications by prominent investigators on each of the approximately 50 enzymes discussed in this review, it was impossible to cite a majority of them.

  5. 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...

  6. HTPEM Fuel Cell Impedance

    DEFF Research Database (Denmark)

    Vang, Jakob Rabjerg

    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...... cells through experimental studies and mathematical modelling. These studies all revolve around the electrochemical impedance spectroscopy (EIS) characterisation method. EIS is performed by applying a sinusoidal current or voltage signal to the fuel cell and calculating the impedance from the response...

  7. [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.

  8. Multiple granular cell tumor.

    Science.gov (United States)

    Jones, J K; Kuo, T T; Griffiths, C M; Itharat, S

    1980-10-01

    Eleven cases of granular cell tumor were reviewed. In two of the cases multiple sites of involvement were seen. The tumor occurred in the oral cavity in both of these cases and each was initially wrongly diagnosed as squamous cell carcinoma. The most common site was the subcutaneous tissue (nine patients) and the tongue was involved in three cases. In one patient the parotid gland was involved. Eight of the patients were females and three were males; seven were black and four were white. The importance of differentiating between squamous cell carcinoma and granular cell tumor is stressed, as is the need for a simple wide surgical excision. PMID:7421377

  9. Live-cell luciferase assay of drug resistant cells

    OpenAIRE

    sprotocols

    2015-01-01

    To date, multiplexing cell-based assay is essential for high-throughput screening of molecular targets. Measuring multiple parameters of a single sample increases consistency and decrease time and cost of assay. Functional assay of living cell is useful as a first step of multiplexing assay, because live-cell assay allows following second assay using cell lysate or stained cell. However, live-cell assay of drug resistant cells that are highly activated of drug efflux mechanisms is sometimes u...

  10. [Dendritic cells and interaction with other cell types. Immune tolerance].

    Science.gov (United States)

    Guerder, S

    2001-07-01

    T cell tolerance to self antigen is mainly established in the thymus were self-reactive T cells are deleted. Interdigitating dendritic cells and medulary epithelial cells are directly involved in the deletion process. Some self-reactive T cells escape, however this thymic censorship and enter the peripheral pool of naive T cells. Multiple mechanisms are also at play in the periphery to control this potentially armfull T cells, this include deletion and immune deviation.

  11. 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...

  12. Stem cells - biological update and cell therapy progress

    OpenAIRE

    GIRLOVANU, MIHAI; Susman, Sergiu; Soritau, Olga; RUS-CIUCA, DAN; MELINCOVICI, CARMEN; CONSTANTIN, ANNE-MARIE; Carmen Mihaela MIHU

    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 t...

  13. Liver epithelial cells inhibit proliferation and invasiveness of hepatoma cells.

    Science.gov (United States)

    Jeng, Kuo-Shyang; Jeng, Chi-Juei; Jeng, Wen-Juei; Sheen, I-Shyan; Li, Shih-Yun; Hung, Zih-Hang; Hsiau, Hsin-I; Yu, Ming-Che; Chang, Chiung-Fang

    2016-03-01

    Hepatocellular carcinoma (HCC) is a worldwide malignancy with poor prognosis. Liver progenitors or stem cells could be a potential therapy for HCC treatment since they migrate toward tumors. Rat liver epithelial (RLE) cells have both progenitor and stem cell-like properties. Therefore, our study elucidated the therapeutic effect of RLE cells in rat hepatoma cells. RLE cells were isolated from 10-day old rats and characterized for stem cell marker expression. RLE cells and rat hepatoma cells (H4-IIE-C3 cells) were co-cultured and divided into four groups with different ratios of RLE and hepatoma cells. Group A had only rat hepatoma cells as a control group. The ratios of rat hepatoma and RLE cells in group B, C and D were 5:1, 1:1 and 1:5, respectively. Effective inhibition of cell proliferation and migration was found in group D when compared to group A. There was a significant decrease in Bcl2 expression and increase in late apoptosis of rat hepatoma cells when adding more RLE cells. RLE cells reduced cell proliferation and migration of rat hepatoma cells. These results suggested that RLE cells could be used as a potential cell therapy. PMID:26647726

  14. Polarised cells, polarised views: Asymmetric cell division in hematopoietic cells.

    Directory of Open Access Journals (Sweden)

    Kim ePham

    2014-02-01

    Full Text Available It has long been recognised that alterations in cell shape and polarity play important roles in coordinating lymphocyte functions. In the last decade a new aspect of lymphocyte polarity, termed Asymmetric Cell Division (ACD, has attracted much attention. ACD has previously been shown to dictate or influence many aspects of development in model organisms such as the worm and the fly, and to be disrupted in disease. Recent observations that ACD also occurs in lymphocytes led to exciting speculations that ACD might influence lymphocyte differentiation and function, and leukaemia. However, dissecting the role that ACD might play in these activities is not straightforward, and the evidence to date for a functional role in lymphocyte fate determination has been controversial. In this review, we discuss the evidence to date for ACD in lymphocytes, and how it might influence lymphocyte fate. We also discuss current gaps in our knowledge, and suggest approaches to definitively test the physiological role of ACD in lymphocytes.

  15. 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...

  16. 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. PMID:27590152

  17. The new stem cell biology.

    OpenAIRE

    Quesenberry, Peter J.; Colvin, Gerald A; Lambert, Jean-Francois; Frimberger, Angela E.; Dooner, Mark S.; Mcauliffe, Christina I.; Miller, Caroline; Becker, Pamela; Badiavas, Evangelis; Falanga, Vincent J.; Elfenbein, Gerald; Lum, Lawrence G.

    2002-01-01

    Recent studies have indicated that bone marrow stem cells are capable of generating muscle, cardiac, hepatic, renal, and bone cells. Purified hematopoietic stem cells have generated cardiac and hepatic cells and reversed disease manifestations in these tissues. Hematopoietic stem cells also alter phenotype with cell cycle transit or circadian phase. During a cytokine stimulated cell cycle transit, reversible alterations of differentiation and engraftment occur. Primitive hematopoietic stem ce...

  18. 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...

  19. Tracking Down Mutations Cell by Cell.

    Science.gov (United States)

    Kosik, Kenneth S

    2016-03-16

    Using somatic cell nuclear transfer, Hazen et al. (2016) examined clonally expanded single neurons for mutations and found ∼100 mutations from a variety of classes. Post-mitotic mutations in individual neurons represent an exploratory direction for finding fundamental origins of neurodegeneration. PMID:26985720

  20. 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

  1. 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.

  2. 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...

  3. 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.

  4. 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…

  5. 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...

  6. 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…

  7. Printed paper photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Huebler, Arved; Trnovec, Bystrik; Zillger, Tino; Ali, Moazzam; Wetzold, Nora [Inistitute for Print and Media Technology, Chemnitz University of Technology, Chemnitz (Germany); Mingebach, Markus; Wagenpfahl, Alexander; Deibel, Carsten [Experimental Physics VI, Julius-Maximilians-University of Wuerzburg (Germany); Dyakonov, Vladimir [Experimental Physics VI, Julius-Maximilians-University of Wuerzburg (Germany); Bavarian Center for Applied Energy Research e.V. (ZAE Bayern), Wuerzburg (Germany)

    2011-11-15

    Polymer/fullerene solar cells are printed on paper using a combination of gravure and flexographic printing techniques. The printed paper photovoltaic cells are free from expensive electrodes made with indium-tin oxide, silver, or gold. Oxidized zinc film is used as the electron-collecting layer. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. 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.

  9. 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.

  10. 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.

  11. 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....

  12. Cell Maintenance Systems

    Science.gov (United States)

    Morrison, D. R.

    1985-01-01

    Living human cells require attachment to a suitable surface and special culture conditions in order to grow. These requirements are modified and amplified when cells are taken into a weightless environment. Special handling and maintenance systems are required for routine laboratory procedures conducted in the Orbiter and in the Spacelab. Methods were developed to maintain cells in special incubators designed for the Orbiter middeck, however, electrophoresis and other experiments require cells to be harvested off of the culture substrate before they can be processed or used. The cell transport assembly (CTA) was flown on STS-8, and results show that improvements are required to maintain adequate numbers of cells in this device longer than 48 hours. The life sciences middeck centrifuge probably can be used, but modifications will be required to transfer cells from the CTA and keep the cells sterile. Automated systems such as the Skylab SO-15 flight hardware and crew operated systems are being evaluated for use on the Space Shuttle, Spacelab, and Space Station research modules.

  13. 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

  14. Cell Proliferation in Neuroblastoma

    Directory of Open Access Journals (Sweden)

    Laura L. Stafman

    2016-01-01

    Full Text Available Neuroblastoma, the most common extracranial solid tumor of childhood, continues to carry a dismal prognosis for children diagnosed with advanced stage or relapsed disease. This review focuses upon factors responsible for cell proliferation in neuroblastoma including transcription factors, kinases, and regulators of the cell cycle. Novel therapeutic strategies directed toward these targets in neuroblastoma are discussed.

  15. Patterning Stem Cell Differentiation

    OpenAIRE

    Vunjak-Novakovic, Gordana

    2008-01-01

    Regulation of cell differentiation and assembly remains a fundamental question in developmental biology. Now, a report from the Chen laboratory (Ruiz and Chen, 2008) describes an approach that represents a major step toward a more profound understanding of the geometric-force control of stem cell differentiation.

  16. 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.

  17. Solar cell concentrating system

    International Nuclear Information System (INIS)

    This study reviews fabrication techniques and testing facilities for different solar cells under concentration which have been developed and tested. It is also aimed to examine solar energy concentrators which are prospective candidates for photovoltaic concentrator systems. This may provide an impetus to the scientists working in the area of solar cell technology

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Fifty cell test facility

    Energy Technology Data Exchange (ETDEWEB)

    Arntzen, J. D.; Kolba, V. M.; Miller, W. E.; Gay, E. C.

    1980-07-01

    This report describes the design of a facility capable of the simultaneous testing of up to 50 high-temperature (400 to 500/sup 0/C) lithium alloy/iron sulfide cells; this facility is located in the Chemical Engineering Division of Argonne National Laboratory (ANL). The emphasis will be on the lifetime testing of cells fabricated by ANL and industrial contractors to acquire statistical data on the performance of cells of various designs. A computer-based data-acquisition system processes the cell performance data generated from the cells on test. The terminals and part of the data-acquisition equipment are housed in an air-conditioned enclosure adjacent to the testing facility; the computer is located remotely.

  3. 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...

  4. 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 appear...... to regulate cell fusions, including receptors and ligands, membrane domain organizing proteins, proteases, signaling molecules and fusogenic proteins forming alpha-helical bundles that bring membranes close together. The syncytin family of proteins represent true fusogens and the founding member, syncytin-1......, has been documented to be involved in fusions between placental trophoblasts, between cancer cells and between cancer cells and host ells. We review the literature with emphasis on the syncytin family and propose that syncytins may represent universal fusogens in primates and rodents, which work...

  5. Metallization of bacteria cells

    Institute of Scientific and Technical Information of China (English)

    LI; Xiangfeng; (黎向锋); LI; Yaqin; (李雅芹); CAI; Jun; (蔡军); ZHANG; Deyuan; (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.

  6. 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.

  7. Nanoelectrochemistry of mammalian cells.

    Science.gov (United States)

    Sun, Peng; Laforge, François O; Abeyweera, Thushara P; Rotenberg, Susan A; Carpino, James; Mirkin, Michael V

    2008-01-15

    There is a significant current interest in development of new techniques for direct characterization of the intracellular redox state and high-resolution imaging of living cells. We used nanometer-sized amperometric probes in combination with the scanning electrochemical microscope (SECM) to carry out spatially resolved electrochemical experiments in cultured human breast cells. With the tip radius approximately 1,000 times smaller than that of a cell, an electrochemical probe can penetrate a cell and travel inside it without apparent damage to the membrane. The data demonstrate the possibility of measuring the rate of transmembrane charge transport and membrane potential and probing redox properties at the subcellular level. The same experimental setup was used for nanoscale electrochemical imaging of the cell surface. PMID:18178616

  8. Digital Microfluidic Cell Culture.

    Science.gov (United States)

    Ng, Alphonsus H C; Li, Bingyu Betty; Chamberlain, M Dean; Wheeler, Aaron R

    2015-01-01

    Digital microfluidics (DMF) is a droplet-based liquid-handling technology that has recently become popular for cell culture and analysis. In DMF, picoliter- to microliter-sized droplets are manipulated on a planar surface using electric fields, thus enabling software-reconfigurable operations on individual droplets, such as move, merge, split, and dispense from reservoirs. Using this technique, multistep cell-based processes can be carried out using simple and compact instrumentation, making DMF an attractive platform for eventual integration into routine biology workflows. In this review, we summarize the state-of-the-art in DMF cell culture, and describe design considerations, types of DMF cell culture, and cell-based applications of DMF. PMID:26643019

  9. Photovoltaic solar cell

    Science.gov (United States)

    Nielson, Gregory N.; Gupta, Vipin P.; Okandan, Murat; Watts, Michael R.

    2015-09-08

    A photovoltaic solar concentrator is disclosed with one or more transverse-junction solar cells (also termed point contact solar cells) and a lens located above each solar cell to concentrate sunlight onto the solar cell to generate electricity. Piezoelectric actuators tilt or translate each lens to track the sun using a feedback-control circuit which senses the electricity generated by one or more of the solar cells. The piezoelectric actuators can be coupled through a displacement-multiplier linkage to provide an increased range of movement of each lens. Each lens in the solar concentrator can be supported on a frame (also termed a tilt plate) having three legs, with the movement of the legs being controlled by the piezoelectric actuators.

  10. PEM regenerative fuel cells

    Science.gov (United States)

    Swette, Larry L.; Laconti, Anthony B.; McCatty, Stephen A.

    1993-11-01

    This paper will update the progress in developing electrocatalyst systems and electrode structures primarily for the positive electrode of single-unit solid polymer proton exchange membrane (PEM) regenerative fuel cells. The work was done with DuPont Nafion 117 in complete fuel cells (40 sq cm electrodes). The cells were operated alternately in fuel cell mode and electrolysis mode at 80 C. In fuel cell mode, humidified hydrogen and oxygen were supplied at 207 kPa (30 psi); in electrolysis mode, water was pumped over the positive electrode and the gases were evolved at ambient pressure. Cycling data will be presented for Pt-Ir catalysts and limited bifunctional data will be presented for Pt, Ir, Ru, Rh, and Na(x)Pt3O4 catalysts as well as for electrode structure variations.

  11. 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.

  12. 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.

  13. [Merkel cell skin carcinoma].

    Science.gov (United States)

    Krejcí, K; Zadrazil, J; Tichý, T; Horák, P; Ciferská, H; Hodulová, M; Zezulová, M; Zlevorová, M

    2010-01-01

    Merkel cell carcinoma is a rare tumour of the skin. It affects predominantly elderly Caucasian males on sun-exposed areas of the skin. Distinctively more frequent and at significantly lower age, its incidence is higher in immunocompromised patients. In these patients we often observe the highly aggressive course of Merkel cell carcinoma and a fatal outcome. The incidence of Merkel cell carcinoma has been rising in recent years and is more dramatic than the increased incidence of cutaneous melanoma. More than one-third of Merkel cell carcinoma patients will die from this cancer, making it twice as lethal as melanoma. The malignant transformation of Merkel cells is currently thought to be related to an infection with Merkel cell polyomavirus. In the early stage the discreet clinical picture may be contrary to extensive microscopic invasion and this seemingly benign appearance can delay diagnosis or increase the risk of insufficient tumour excision. The diagnosis is definitely confirmed by histological evaluation and immunohistochemical tests. A typical feature is the tendency of Merkel cell carcinoma to frequent local recurrence and early metastasizing into regional lymph nodes with subsequent tumour generalization. The mainstay of therapy is radical excision of the tumour and adjuvant radiotherapy targeted at the site of primary incidence and local draining lymph nodes. The efficacy of different chemotherapy protocols in Merkel cell carcinoma is limited and the median survival rate is measured in months. In the future, prophylaxis with vaccination against Merkel cell polyomavirus will hopefully be possible in high-risk patients, as well as therapeutic usage of antisense oligonucleotides or microRNAs, eventually complete Merkel cell carcinoma elimination by affecting the tumour suppressor gene Atonal homolog 1 expression. The staging of the tumour at time of diagnosis is the most important prognostic factor. In this respect, the importance of preventative skin

  14. Langerhans' cells, veiled cells, and interdigitating cells in the mouse recognized by a monoclonal antibody

    OpenAIRE

    1986-01-01

    An mAb, NLDC-145, is described that specifically reacts with a group of nonlymphoid dendritic cells including Langerhans cells (LC), veiled cells (VC), and interdigitating cells (IDC). The antibody does not react with precursor cells in bone marrow and blood. Macrophages are not stained by the antibody, but a subpopulation of Ia+ peritoneal exudate cells is recognized. Possible relationships of the various nonlymphoid dendritic cell (NLDC) types are discussed.

  15. 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.

  16. Human Liver Stem Cells Suppress T-Cell Proliferation, NK Activity, and Dendritic Cell Differentiation

    OpenAIRE

    Stefania Bruno; Cristina Grange; Marta Tapparo; Chiara Pasquino; Renato Romagnoli; Ennia Dametto; Antonio Amoroso; Ciro Tetta; Giovanni Camussi

    2016-01-01

    Human liver stem cells (HLSCs) are a mesenchymal stromal cell-like population resident in the adult liver. Preclinical studies indicate that HLSCs could be a good candidate for cell therapy. The aim of the present study was to evaluate the immunogenicity and the immunomodulatory properties of HLSCs on T-lymphocytes, natural killer cells (NKs), and dendritic cells (DCs) in allogeneic experimental settings. We found that HLSCs inhibited T-cell proliferation by a mechanism independent of cell co...

  17. Diffusion inside living human cells

    DEFF Research Database (Denmark)

    Leijnse, N.; Jeon, J. -H.; Loft, Steffen;

    2012-01-01

    cells. For these cells the exact diffusional pattern of a particular granule depends on the physiological state of the cell and on the localization of the granule within the cytoplasm. Granules located close to the actin rich periphery of the cell move less than those located towards to the center...... of the cell or within the nucleus. Also, granules in cells which are stressed by intense laser illumination or which have attached to a surface for a long period of time move in a more restricted fashion than those within healthy cells. For granules diffusing in healthy cells, in regions away from the cell...

  18. 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.

  19. 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...

  20. 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

  1. Mesenchymal stem cells: cell biology and potential use in therapy

    DEFF Research Database (Denmark)

    Kassem, Moustapha; Kristiansen, Malthe; Abdallah, Basem M

    2004-01-01

    Mesenchymal stem cells are clonogenic, non-haematopoietic stem cells present in the bone marrow and are able to differentiate into multiple mesoderm-type cell lineages e.g. osteoblasts, chondrocytes, endothelial-cells and also non-mesoderm-type lineages e.g. neuronal-like cells. Several methods...... are currently available for isolation of the mesenchymal stem cells based on their physical and immunological characteristics. Because of the ease of their isolation and their extensive differentiation potential, mesenchymal stem cells are among the first stem cell types to be introduced in the clinic. Recent...... studies have demonstrated that the life span of mesenchymal stem cells in vitro can be extended by increasing the levels of telomerase expression in the cells and thus allowing culture of large number of cells needed for therapy. In addition, it has been shown that it is possible to culture the cells...

  2. 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.

  3. Dedifferentiation of committed epithelial cells into stem cells in vivo

    OpenAIRE

    Tata, Purushothama Rao; Mou, Hongmei; Pardo-Saganta, Ana; Zhao, Rui; Prabhu, Mythili; Law, Brandon M.; Vinarsky, Vladimir; Josalyn L Cho; Breton, Sylvie; Sahay, Amar; Medoff, Benjamin D.; Rajagopal, Jayaraj

    2013-01-01

    Summary Cellular plasticity contributes to the regenerative capacity of plants, invertebrates, teleost fishes, and amphibians. In vertebrates, differentiated cells are known to revert into replicating progenitors, but these cells do not persist as stable stem cells. We now present evidence that differentiated airway epithelial cells can revert into stable and functional stem cells in vivo. Following the ablation of airway stem cells, we observed a surprising increase in the proliferation of c...

  4. Dedifferentiation of committed epithelial cells into stem cells in vivo

    OpenAIRE

    Tata, Purushothama Rao; Mou, Hongmei; Pardo-Saganta, Ana; Zhao, Rui; Prabhu, Mythili; Law, Brandon M.; Vinarsky, Vladimir; Josalyn L Cho; Breton, Sylvie; Sahay, Amar; Medoff, Benjamin D.; Rajagopal, Jayaraj

    2014-01-01

    Summary Cellular plasticity contributes to the regenerative capacity of plants, invertebrates, teleost fishes, and amphibians. In vertebrates, differentiated cells are known to revert into replicating progenitors, but these cells do not persist as stable stem cells. We now present evidence that differentiated airway epithelial cells can revert into stable and functional stem cells in vivo. Following the ablation of airway stem cells, we observed a surprising increase in the proliferation of c...

  5. Defective alloantigen-presenting capacity of 'Langerhans cell histiocytosis cells'.

    OpenAIRE

    Yu, R C; Morris, J F; Pritchard, J.; Chu, T C

    1992-01-01

    The functional activity of skin cells derived from an infant who died of multisystem Langerhans cell histiocytosis (LCH) was examined. Involved and non-involved skin was obtained at postmortem examination within three hours of death; normal epidermal Langerhans cells and 'LCH cells' were separated by means of dispase digestion. The functional activity of different populations of CD1a positive cells was assessed using the conventional six day allogeneic mixed cell reaction. Compared with Lange...

  6. Differentiation of human embryonic stem cells into insulin- secreting cells

    OpenAIRE

    S Mollamohammadi; Massumi, M.; H Jafary; Baharvand, H.

    2006-01-01

    Introduction: Type I diabetes mellitus is caused by autoimmune destruction of the insulin-producing β-cells. A new potential method for curing the disease is transplantation of differentiated insulin- secreting cells from human embryonic stem cells. Methods: Human embryonic stem cell lines (Royan H1) were used to produce embryoid bodies. Differentiation carried out by growth factor-mediated selection of nestin positive cells. In final stage, these cells were expanded in the presence of bFGF, ...

  7. The Cell Surface Proteome of Human Mesenchymal Stromal Cells

    OpenAIRE

    Christian Niehage; Charlotte Steenblock; Theresia Pursche; Martin Bornhäuser; Denis Corbeil; Bernard Hoflack

    2011-01-01

    BACKGROUND: Multipotent human mesenchymal stromal cells (hMSCs) are considered as promising biological tools for regenerative medicine. Their antibody-based isolation relies on the identification of reliable cell surface markers. METHODOLOGY/PRINCIPAL FINDINGS: To obtain a comprehensive view of the cell surface proteome of bone marrow-derived hMSCs, we have developed an analytical pipeline relying on cell surface biotinylation of intact cells using cell impermeable, cleavable sulfo-NHS-SS-bio...

  8. 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.

  9. 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.

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

    Institute of Scientific and Technical Information of China (English)

    WANG JiongKun; XING FeiYue

    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.

  11. 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

  12. Stem Cells and Cancer

    International Nuclear Information System (INIS)

    Stem cell research has thrived over the last years due to their therapeutic and regenerative potential. Scientific breakthroughs in the field are immediately translated from the scientific journals to the mass media, which is not surprising as the characterisation of the molecular mechanisms that regulate the biology of stem cells is crucial for the treatment of degenerative and cardiovascular diseases, as well as cancer. In the Molecular Oncology Unit at Ciemat we work to unravel the role of cancer stem cells in tumour development, and to find new antitumor therapies. (Author)

  13. 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.

  14. Limbal Stem Cell Therapy

    OpenAIRE

    Kringlegarden, Hilde Grane

    2013-01-01

    It is widely accepted today that stem cells in the adult corneal epithelium is located to the limbus. No specific marker of limbal epithelial cells (LESCs) has been identified, yet many have been suggested, including ΔNp63α, ABCG2, vimentin and notch 1. Negative markers include amongst others the differentiation markers Ck3 and Ck12. The lack of an identified specific marker elucidates the need for establishment of more exact molecular markers of LESCs. Limbal stem cell deficiency (LSCD) may ...

  15. 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.

  16. 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.

  17. 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)

  18. Stem cells and transplant arteriosclerosis.

    Science.gov (United States)

    Xu, Qingbo

    2008-05-01

    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.

  19. 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

  20. CD81 is dispensable for hepatitis C virus cell-to-cell transmission in hepatoma cells.

    Science.gov (United States)

    Witteveldt, Jeroen; Evans, Matthew J; Bitzegeio, Julia; Koutsoudakis, George; Owsianka, Ania M; Angus, Allan G N; Keck, Zhen-Yong; Foung, Steven K H; Pietschmann, Thomas; Rice, Charles M; Patel, Arvind H

    2009-01-01

    Hepatitis C virus (HCV) infects cells by the direct uptake of cell-free virus following virus engagement with specific cell receptors such as CD81. Recent data have shown that HCV is also capable of direct cell-to-cell transmission, although the role of CD81 in this process is disputed. Here, we generated cell culture infectious strain JFH1 HCV (HCVcc) genomes carrying an alanine substitution of E2 residues W529 or D535 that are critical for binding to CD81 and infectivity. Co-cultivation of these cells with naïve cells expressing enhanced green fluorescent protein (EGFP) resulted in a small number of cells co-expressing both EGFP and HCV NS5A, showing that the HCVcc mutants are capable of cell-to-cell spread. In contrast, no cell-to-cell transmission from JFH1(DeltaE1E2)-transfected cells occurred, indicating that the HCV glycoproteins are essential for this process. The frequency of cell-to-cell transmission of JFH1(W529A) was unaffected by the presence of neutralizing antibodies that inhibit E2-CD81 interactions. By using cell lines that expressed little or no CD81 and that were refractive to infection with cell-free virus, we showed that the occurrence of viral cell-to-cell transmission is not influenced by the levels of CD81 on either donor or recipient cells. Thus, our results show that CD81 plays no role in the cell-to-cell spread of HCVcc and that this mode of transmission is shielded from neutralizing antibodies. These data suggest that therapeutic interventions targeting the entry of cell-free HCV may not be sufficient in controlling an ongoing chronic infection, but need to be complemented by additional strategies aimed at disrupting direct cell-to-cell viral transmission. PMID:19088272

  1. Fuel cells: Problems and prospects

    OpenAIRE

    Shukla, AK; Ramesh, KV; Kannan, AM

    1986-01-01

    n recent years, fuel cell technology has advanced significantly. Field trials on certain types of fuel cells have shown promise for electrical use. This article reviews the electrochemistry, problems and prospects of fuel cell systems.

  2. Stem Cell Transplants (For Teens)

    Science.gov (United States)

    ... Can I Help a Friend Who Cuts? Stem Cell Transplants KidsHealth > For Teens > Stem Cell Transplants Print ... it Take to Recover? Coping What Are Stem Cells? As you probably remember from biology class, every ...

  3. Kinetics of adrenal medullary cells.

    OpenAIRE

    Verhofstad, A A

    1993-01-01

    The adrenal medulla of mammals has a heterogeneous population of cells. In adults most are epithelial cells containing a particular type of cytoplasmic granule. Based on a variety of cytochemical and ultrastructural studies it is now accepted that 2 different adrenal medullary chromaffin cell types can be distinguished, i.e. noradrenaline (NA) and adrenaline (A) synthesising and storing cells. Other cell types present in the adrenal medulla include neuronal elements comprising either cell bod...

  4. 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.

  5. Pancreatic Stem Cells Remain Unresolved

    OpenAIRE

    Jiang, Fang-Xu; Morahan, Grant

    2014-01-01

    Diabetes mellitus is caused by absolute (type 1) or relative (type 2) deficiency of insulin-secreting islet β cells. An ideal treatment of diabetes would, therefore, be to replace the lost or deficient β cells, by transplantation of donated islets or differentiated endocrine cells or by regeneration of endogenous islet cells. Due to their ability of unlimited proliferation and differentiation into all functional lineages in our body, including β cells, embryonic stem cells and induced pluripo...

  6. Mast cells in bacterial infections

    OpenAIRE

    Rönnberg, Elin

    2014-01-01

    Mast cells are implicated in immunity towards bacterial infection, but the molecular mechanisms by which mast cells contribute to the host response are only partially understood. Previous studies have examined how mast cells react to purified bacterial cell wall components, such as peptidoglycan and lipopolysaccharide. To investigate how mast cells react to live bacteria we co-cultured mast cells and the gram-positive bacteria Streptococcus equi (S. equi) and Staphylococcus aureus (S. aureus)...

  7. FUEL CELLS IN ENERGY PRODUCTION

    OpenAIRE

    Huang, Xiaoyu

    2011-01-01

    The purpose of this thesis is to study fuel cells. They convert chemical energy directly into electrical energy with high efficiency and low emmission of pollutants. This thesis provides an overview of fuel cell technology.The basic working principle of fuel cells and the basic fuel cell system components are introduced in this thesis. The properties, advantages, disadvantages and applications of six different kinds of fuel cells are introduced. Then the efficiency of each fuel cell is p...

  8. 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.

  9. 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.

  10. 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...

  11. 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...

  12. 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...... responses to regulate processes including branching morphogenesis and alveolar differentiation. Malignant transformation of the breast is also associated with significant matrix remodeling and a progressive stiffening of the stroma that can enhance mammary epithelial cell growth, perturb breast tissue...

  13. 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...

  14. 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.

  15. 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)

  16. Familial germ cell tumor

    Directory of Open Access Journals (Sweden)

    Sanju Cyriac

    2012-01-01

    Full Text Available Familial testicular germ cell tumors are well known in literature. Only few cases are reported where both brother and sister of the same family suffered from germ cell malignancies. We present a family where the proband is a survivor of ovarian dysgerminoma stage IA. Her elder male sibling became acutely ill and was detected to have disseminated testicular malignancy with grossly elevated markers and vegetations in the mitral valve leaflets. Despite all measures he could not be saved. Presence of germ cell malignancies in the siblings of different sex in the same family points toward a genetic susceptibility. Literature review revealed only six similar cases. A discussion regarding the rare occurrence of familial germ cell malignancies with the affected family members may be worthwhile.

  17. Renal Medullary Interstitial Cells

    Science.gov (United States)

    Rao, Reena; Hao, Chuan-Ming; Breyer, Matthew D.

    2007-04-01

    Renal medullary interstitial cells (RMICs) are specialized fibroblast-like cells that reside in the renal medulla among the vasa recta, the thin limbs of Henle's loop, and medullary collecting ducts. These cells are characterized by abundant lipid droplets in the cytoplasm. The lipid droplets are composed of triglycerides, cholesterol esters and free long-chain fatty acids, including arachidonic acid. RMICs are also a major site of cyclooxygenase2 (COX-2) expression, and thus a major site of COX-2 derived prostanoid biosynthesis. RMICs are also a potential target of hormones such as angiotensin II and endothelin. The RMIC COX-2 expression and the abundance of lipid droplets change with salt and water intake. These properties of RMICs are consistent with an important role of these cells in modulating physiologic and pathologic processes of the kidney.

  18. Langerhans cell histiocytosis

    OpenAIRE

    Xiao-ling YAN

    2014-01-01

    A case report and literature review. We present a boy with a multisystemic presentation of Langerhans cell histiocytosis and severe pulmonary lesion.Skin lesion helped to suspect and confirm diagnosis by scalpbiopsy. Chemotherapy was important for favorable result.

  19. [Pulmonary Langerhans cell histiocytosis].

    Science.gov (United States)

    Popper, H H

    2015-09-01

    Pulmonary Langerhans cell histiocytosis is regarded as a reactive proliferation of the dendritic Langerhans cell population stimulated by chronic tobacco-derived plant proteins due to incomplete combustion but can also occur in childhood as a tumor-like systemic disease. Currently, both these forms cannot be morphologically distinguished. In the lungs a nodular proliferation of Langerhans cells occurs in the bronchial mucosa and also peripherally in the alveolar septa with an accompanying infiltration by eosinophilic granulocytes and destruction of the bronchial wall. Langerhans cells can be selectively detected with antibodies against CD1a and langerin. In the reactive isolated pulmonary form, abstinence from tobacco smoking in most patients leads to regression of infiltration and improvement of symptoms. In high-resolution computed tomography (HRCT) the small star-like scars can still be detected even after complete cessation of tobacco smoking. PMID:26289803

  20. Merkel Cell Carcinoma

    Science.gov (United States)

    ... of the Year Award Arnold P. Gold Foundation Humanism in Medicine Award Diversity Mentorship Program Eugene Van ... 300 PUVA treatments. What causes Merkel cell carcinoma? Scientists are still studying what causes this skin cancer. ...

  1. Sickle cell test

    Science.gov (United States)

    Sickledex; Hgb S test ... This test is done to tell if a person has abnormal hemoglobin that causes sickle cell disease and sickle ... and no symptoms, or only mild ones. This test does not tell the difference between these two ...

  2. 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.

  3. 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.

  4. 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...

  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. 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.

  7. 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.

  8. Mast cells and company.

    Science.gov (United States)

    Jönsson, Friederike; Daëron, Marc

    2012-01-01

    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 be considered as important players in allergy. This view markedly changes our understanding of allergic diseases and, possibly, their treatment.

  9. Metaphyseal giant cell tumor

    International Nuclear Information System (INIS)

    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. (Author)

  10. Lipocytes (fat cells) (image)

    Science.gov (United States)

    ... to energy output, there is no expansion of fat cells (lipocytes) to accommodate excess. It is only when more calories are taken in than used that the extra fat is stored in the lipocytes and the person ...

  11. 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.

  12. Nanodiamond internalization in cells and the cell uptake mechanism

    International Nuclear Information System (INIS)

    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

  13. 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.

  14. 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.

  15. 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.

  16. Transgelin-2 in B-Cells Controls T-Cell Activation by Stabilizing T Cell - B Cell Conjugates

    Science.gov (United States)

    Chae, Myoung-Won; Kim, Hye-Ran; Kim, Chang-Hyun; Jun, Chang-Duk; Park, Zee-Yong

    2016-01-01

    The immunological synapse (IS), a dynamic and organized junction between T-cells and antigen presenting cells (APCs), is critical for initiating adaptive immunity. The actin cytoskeleton plays a major role in T-cell reorganization during IS formation, and we previously reported that transgelin-2, an actin-binding protein expressed in T-cells, stabilizes cortical F-actin, promoting T-cell activation in response to antigen stimulation. Transgelin-2 is also highly expressed in B-cells, although no specific function has been reported. In this study, we found that deficiency in transgelin-2 (TAGLN2-/-) in B-cells had little effect on B-cell development and activation, as measured by the expression of CD69, MHC class II molecules, and CD80/86. Nevertheless, in B-cells, transgelin-2 accumulated in the IS during the interaction with T-cells. These results led us to hypothesize that transgelin-2 may also be involved in IS stability in B-cells, thereby influencing T-cell function. Notably, we found that transgelin-2 deficiency in B-cells reduced T-cell activation, as determined by the release of IL-2 and interferon-γ and the expression of CD69. Furthermore, the reduced T-cell activation was correlated with reduced B-cell–T-cell conjugate formation. Collectively, these results suggest that actin stability in B-cells during IS formation is critical for the initiation of adaptive T-cell immunity. PMID:27232882

  17. Nonislet Cell Tumor Hypoglycemia

    OpenAIRE

    Johnson Thomas; Salini C. Kumar

    2013-01-01

    Nonislet cell tumor hypoglycemia (NICTH) is a rare cause of hypoglycemia. It is characterized by increased glucose utilization by tissues mediated by a tumor resulting in hypoglycemia. NICTH is usually seen in large mesenchymal tumors including tumors involving the GI tract. Here we will discuss a case, its pathophysiology, and recent advances in the management of NICTH. Our patient was diagnosed with poorly differentiated squamous cell carcinoma of esophagus. He continued to be hypoglycemic ...

  18. Plasma cell leukemia

    OpenAIRE

    Gertz, Moria A.; Buadi, Francis K.

    2010-01-01

    Plasma cell leukemia (PCL) is a rare, yet aggressive plasma cell (PC) neoplasm, variant of multiple myeloma (MM), characterized by high levels of PCs circulating in the peripheral blood. PCL can either originate de novo (primary PCL) or as a secondary leukemic transformation of MM (secondary PCL). Presenting signs and symptoms are similar to those seen in MM such as renal insufficiency, hypercalcemia, lytic bone lesions, anemia, and thrombocytopenia, but can also include hepatomegaly and sple...

  19. 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.

  20. 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.

  1. 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.

  2. NK Cells and Trophoblasts

    OpenAIRE

    Parham, Peter

    2004-01-01

    In placental mammals, viviparity—the production of living young within the mother's body—evolved under the auspices of the immune system. Elements of immunity were incorporated, giving pregnancy a mildly inflammatory character. Formation of the placenta, the organ that feeds the fetus, involves a cooperation between maternal natural killer (NK) cells and fetal trophoblast cells that remodels the blood supply. Recent research reveals that this process and human reproductive success are influen...

  3. 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....

  4. Familial germ cell tumor

    OpenAIRE

    Sanju Cyriac; Rejeev Rajendranath; A. Robert Louis; Sagar, T. G.

    2012-01-01

    Familial testicular germ cell tumors are well known in literature. Only few cases are reported where both brother and sister of the same family suffered from germ cell malignancies. We present a family where the proband is a survivor of ovarian dysgerminoma stage IA. Her elder male sibling became acutely ill and was detected to have disseminated testicular malignancy with grossly elevated markers and vegetations in the mitral valve leaflets. Despite all measures he could not be saved. Presenc...

  5. Langerhans cell histiocytosis

    OpenAIRE

    Aruna, D. R.; G Pushpalatha; Sushma Galgali; Prashanthy,

    2011-01-01

    Langerhans cell histiocytosis (LCH) is a group of rare disorders histologically characterized by the proliferation of Langerhans cells. Multiple organs and systems may be involved by the disease. Typically, there is bone involvement and, less frequently, lesions may be found in the lungs, liver, lymph nodes, skin, and mucosa. Oral soft tissue lesions without bone involvement are rare. We present a case of oral lesions associated with LCH in a young woman.

  6. Pulmonary langerhans cell histiocytosis

    OpenAIRE

    Suri Harpreet S; Yi Eunhee S; Nowakowski Gregorz S; Vassallo Robert

    2012-01-01

    Abstract Pulmonary Langerhans Cell Histiocytosis (PLCH) is a relatively uncommon lung disease that generally, but not invariably, occurs in cigarette smokers. The pathologic hallmark of PLCH is the accumulation of Langerhans and other inflammatory cells in small airways, resulting in the formation of nodular inflammatory lesions. While the overwhelming majority of patients are smokers, mechanisms by which smoking induces this disease are not known, but likely involve a combination of events r...

  7. The Cell Processor

    OpenAIRE

    Hoefler, Torsten

    2006-01-01

    Mainstream processor development is mostly targeted at compatibility and continuity. Thus, the processor market is dominated by x86 compatible CPUs since more than two decades now. Several new concepts tried to gain some market share, but it was not possible to overtake the old compatibility driven concepts. A group of three corporates tries another way to come into the market with a new idea, the cell design. The cell processor is a new try to leverage the increasing amount...

  8. The intestinal stem cell

    OpenAIRE

    Barker, Nick; van de Wetering, Marc; Clevers, Hans

    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 each of these events. While the intestinal epithelium represents the most vigorously renewing adult tissue in mammals, the stem cells that fuel this self-renewal process have been identified only rec...

  9. Intracranial germ cell tumor

    OpenAIRE

    Kreutz, J; Rausin, L.; Weerts, E; Tebache, M; Born, J; Hoyoux, C

    2010-01-01

    Germ cell tumours represent about 3 to 8% of pediatric brain tumours. Occurrence of diabetes insipidus is common in the case of suprasellar germ cell tumors. The diagnosis may be advanced by MRI owing to the location and relatively univocal characteristics of the lesion signal. The existence of a bifocal mass developed in both suprasellar region and pineal zone is highly suggestive of a germinoma. The most important notion is to recognize that at the time of diabetes insipidus diagnosis in a ...

  10. 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.

  11. Cell Processing Engineering for Regenerative Medicine : Noninvasive Cell Quality Estimation and Automatic Cell Processing.

    Science.gov (United States)

    Takagi, Mutsumi

    2016-01-01

    The cell processing engineering including automatic cell processing and noninvasive cell quality estimation of adherent mammalian cells for regenerative medicine was reviewed. Automatic cell processing necessary for the industrialization of regenerative medicine was introduced. The cell quality such as cell heterogeneity should be noninvasively estimated before transplantation to patient, because cultured cells are usually not homogeneous but heterogeneous and most protocols of regenerative medicine are autologous system. The differentiation level could be estimated by two-dimensional cell morphology analysis using a conventional phase-contrast microscope. The phase-shifting laser microscope (PLM) could determine laser phase shift at all pixel in a view, which is caused by the transmitted laser through cell, and might be more noninvasive and more useful than the atomic force microscope and digital holographic microscope. The noninvasive determination of the laser phase shift of a cell using a PLM was carried out to determine the three-dimensional cell morphology and estimate the cell cycle phase of each adhesive cell and the mean proliferation activity of a cell population. The noninvasive discrimination of cancer cells from normal cells by measuring the phase shift was performed based on the difference in cytoskeleton density. Chemical analysis of the culture supernatant was also useful to estimate the differentiation level of a cell population. A probe beam, an infrared beam, and Raman spectroscopy are useful for diagnosing the viability, apoptosis, and differentiation of each adhesive cell. PMID:25373455

  12. Mast cells and COPD.

    Science.gov (United States)

    Mortaz, Esmaeil; Folkerts, Gert; Redegeld, Frank

    2011-08-01

    The pathogenesis of chronic obstructive pulmonary disease (COPD) is based on the innate and adaptive inflammatory immune response to the inhalation of toxic particles and gases. Although tobacco smoking is the primary cause of this inhalation injury, many other environmental and occupational exposures contribute to the pathology of COPD. The immune inflammatory changes associated with COPD are linked to a tissue-repair and -remodeling process that increases mucus production and causes emphysematous destruction of the gas-exchanging surface of the lung. The common form of emphysema observed in smokers begins in the respiratory bronchioles near the thickened and narrowed small bronchioles that become the major site of obstruction in COPD. The inflamed airways of COPD patients contain several inflammatory cells including neutrophils, macrophages, T lymphocytes, and dendritic cells. The relative contribution of mast cells to airway injury and remodeling is not well documented. In this review, an overview is given on the possible role of mast cells and their mediators in the pathogenesis of COPD. Activation of mast cells and mast cell signaling in response to exposure to cigarette smoke is further discussed. PMID:21463700

  13. Fuel cell generator

    International Nuclear Information System (INIS)

    A high temperature solid electrolyte fuel cell generator comprising a housing means defining a plurality of chambers including a generator chamber and a combustion products chamber, a porous barrier separating the generator and combustion product chambers, a plurality of elongated annular fuel cells each having a closed end and an open end with the open ends disposed within the combustion product chamber, the cells extending from the open end through the porous barrier and into the generator chamber, a conduit for each cell, each conduit extending into a portion of each cell disposed within the generator chamber, each conduit having means for discharging a first gaseous reactant within each fuel cell, exhaust means for exhausting the combustion product chamber, manifolding means for supplying the first gaseous reactant to the conduits with the manifolding means disposed within the combustion product chamber between the porous barrier and the exhaust means and the manifolding means further comprising support and bypass means for providing support of the manifolding means within the housing while allowing combustion products from the first and a second gaseous reactant to flow past the manifolding means to the exhaust means, and means for flowing the second gaseous reactant into the generator chamber

  14. Fuel cell; Nenryo denchi

    Energy Technology Data Exchange (ETDEWEB)

    Nakayama, T. [New Energy and Industrial Technology Development Organization, Tokyo (Japan)

    1999-07-20

    More than 100 sets of phosphoric acid fuel cells (PAFC) have been installed by now, and accumulated operation performance exceeding 40 thousand hours, which is regarded as a development target, has been achieved. Further, there are also PAFCs that have achieved continuous operation performance exceeding 9,000 hours, thus being most approachable to practical use. On the other hand, developments of the solid oxide fuel cells (SOFC) and the molten carbonate fuel cells (MCFC), which operate at high temperatures, have high power generation efficiencies due to the capability of operating associatively with gas turbines or vapor turbines, and may use coal gasified gases as fuels, are carried out for an aim of realizing the practical use at the begging of the 21st century. Further, in recent years, researches and developments of the polymer electrolyte fuel cells (PEFC) have been accelerated mainly in vehicle business for the purpose of using PEFC as power sources for movable bodies, and researches and development for accelerative development of cell stacks and power generation systems are executed. In this paper, situations of the researches and developments in respect to the above-mentioned four kinds of fuel cells are summarily introduced. (NEDO)

  15. Turing patterns inside cells.

    Directory of Open Access Journals (Sweden)

    Damián E Strier

    Full Text Available Concentration gradients inside cells are involved in key processes such as cell division and morphogenesis. Here we show that a model of the enzymatic step catalized by phosphofructokinase (PFK, a step which is responsible for the appearance of homogeneous oscillations in the glycolytic pathway, displays Turing patterns with an intrinsic length-scale that is smaller than a typical cell size. All the parameter values are fully consistent with classic experiments on glycolytic oscillations and equal diffusion coefficients are assumed for ATP and ADP. We identify the enzyme concentration and the glycolytic flux as the possible regulators of the pattern. To the best of our knowledge, this is the first closed example of Turing pattern formation in a model of a vital step of the cell metabolism, with a built-in mechanism for changing the diffusion length of the reactants, and with parameter values that are compatible with experiments. Turing patterns inside cells could provide a check-point that combines mechanical and biochemical information to trigger events during the cell division process.

  16. Risk of infertility following fetography and amniofetography

    International Nuclear Information System (INIS)

    297 women were subjected to prenatal diagnosis, in 220 of them amniocentesis was performed to start an amnion cell culture and 77 women (26%) were diagnosed by fetography and amniofetography, respectively. Following intra-amniotic injection of contrast medium abortion occured in 9% and premature delivery in 28.6% of the probands. The perinatal mortality was 13%. After amniocentesis the abortion rate was 3.2% and premature delivery took place in 4.5% of the patients. The perinatal mortality was but slightly increased (2.3%). The differences were statistically secured. Following fetography and amniofetography prophylactic cerclage is recommended

  17. Cloning of a cDNA encoding a novel human nuclear phosphoprotein belonging to the WD-40 family

    DEFF Research Database (Denmark)

    Honoré, B; Leffers, H; Madsen, Peder;

    1994-01-01

    -134]. The protein contains a nuclear targeting signal (KKKGK), and fractionation of transformed human amnion cells (AMA) in karyoplasts and cytoplasts confirmed that it is predominantly localized in the nucleus. Database searching indicated that IEF SSP 9502 is a putative human homologue of the Saccharomyces......We have cloned and expressed in vaccinia virus a cDNA encoding an ubiquitous 501-amino-acid (aa) phosphoprotein that corresponds to protein IEF SSP 9502 (79,400 Da, pI 4.5) in the master 2-D-gel keratinocyte protein database [Celis et al., Electrophoresis 14 (1993) 1091-1198]. The deduced aa...

  18. >Effect of progesterone hormon on cell viability and stem cell activation in dental pulp cells

    OpenAIRE

    Segah Altuntaş; Muhammed Ali Kara; Deniz Selin Aksoy; Zehra Dilşad Çoban; Şefik Güran

    2016-01-01

    Objective: The dental pulp is the part in the center of a tooth made up of living connective tissue and cells called odontoblasts. The vitality of the dentin structure, both during health and after injury, depends on pulp cell activity and the signaling processes that regulate the cell’s behavior. Dental pulp tissue has condensed stem cell activity. Dental pulp stem cells are multipotent stem cells that have the potential to differentiate into a variety of cell types. Several publications hav...

  19. 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].

  20. Involvement of Plant Stem Cells or Stem Cell-Like Cells in Dedifferentiation

    OpenAIRE

    Jiang, Fangwei; Feng, Zhenhua; Liu, Hailiang; Zhu, Jian

    2015-01-01

    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 pro...

  1. 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.

  2. 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 ...

  3. 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.

  4. 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

  5. Recognition and Regulation of T Cells by NK Cells

    Science.gov (United States)

    Pallmer, Katharina; Oxenius, Annette

    2016-01-01

    Regulation of T cell responses by innate lymphoid cells (ILCs) is increasingly documented and studied. Direct or indirect crosstalk between ILCs and T cells early during and after T cell activation can affect their differentiation, polarization, and survival. Natural killer (NK) cells that belong to the ILC1 group were initially described for their function in recognizing and eliminating “altered self” and as source of early inflammatory cytokines, most notably type II interferon. Using signals conveyed by various germ-line encoded activating and inhibitory receptors, NK cells are geared to sense sudden cellular changes that can be caused by infection events, malignant transformation, or cellular stress responses. T cells, when activated by TCR engagement (signal 1), costimulation (signal 2), and cytokines (signal 3), commit to a number of cellular alterations, including entry into rapid cell cycling, metabolic changes, and acquisition of effector functions. These abrupt changes may alert NK cells, and T cells might thereby expose themselves as NK cell targets. Here, we review how activated T cells can be recognized and regulated by NK cells and what consequences such regulation bears for T cell immunity in the context of vaccination, infection, or autoimmunity. Conversely, we will discuss mechanisms by which activated T cells protect themselves against NK cell attack and outline the significance of this safeguard mechanism. PMID:27446081

  6. 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

  7. Cell culture models for study of differentiated adipose cells

    OpenAIRE

    Clynes, Martin

    2014-01-01

    Adipose cells are an important source of mesenchymal stem cells and are important for direct use in research on lipid metabolism and obesity. In addition to use of primary cultures, there is increasing interest in other sources of larger numbers of cells, using approaches including induced pluripotent stem cell differentiation and viral immortalisation.

  8. 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.

  9. 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.

  10. 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

  11. Programmed cell death and cell extrusion in rat duodenum

    DEFF Research Database (Denmark)

    Schauser, Kirsten; Larsson, Lars-Inge

    2005-01-01

    The small intestinal epithelium is continously renewed through a balance between cell division and cell loss. How this balance is achieved is uncertain. Thus, it is unknown to what extent programmed cell death (PCD) contributes to intestinal epithelial cell loss. We have used a battery of techniq...

  12. Glioma cell dispersion is driven by α5 integrin-mediated cell-matrix and cell-cell interactions.

    Science.gov (United States)

    Blandin, Anne-Florence; Noulet, Fanny; Renner, Guillaume; Mercier, Marie-Cécile; Choulier, Laurence; Vauchelles, Romain; Ronde, Philippe; Carreiras, Franck; Etienne-Selloum, Nelly; Vereb, Gyorgy; Lelong-Rebel, Isabelle; Martin, Sophie; Dontenwill, Monique; Lehmann, Maxime

    2016-07-01

    Glioblastoma multiform (GBM) is the most common and most aggressive primary brain tumor. The fibronectin receptor, α5 integrin is a pertinent novel therapeutic target. Despite numerous data showing that α5 integrin support tumor cell migration and invasion, it has been reported that α5 integrin can also limit cell dispersion by increasing cell-cell interaction. In this study, we showed that α5 integrin was involved in cell-cell interaction and gliomasphere formation. α5-mediated cell-cell cohesion limited cell dispersion from spheroids in fibronectin-poor microenvironment. However, in fibronectin-rich microenvironment, α5 integrin promoted cell dispersion. Ligand-occupied α5 integrin and fibronectin were distributed in fibril-like pattern at cell-cell junction of evading cells, forming cell-cell fibrillar adhesions. Activated focal adhesion kinase was not present in these adhesions but was progressively relocalized with α5 integrin as cell migrates away from the spheroids. α5 integrin function in GBM appears to be more complex than previously suspected. As GBM overexpressed fibronectin, it is most likely that in vivo, α5-mediated dissemination from the tumor mass overrides α5-mediated tumor cell cohesion. In this respect, α5-integrin antagonists may be useful to limit GBM invasion in brain parenchyma. PMID:27063097

  13. 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.

  14. β-Cell regeneration through the transdifferentiation of pancreatic cells: Pancreatic progenitor cells in the pancreas.

    Science.gov (United States)

    Kim, Hyo-Sup; Lee, Moon-Kyu

    2016-05-01

    Pancreatic progenitor cell research has been in the spotlight, as these cells have the potential to replace pancreatic β-cells for the treatment of type 1 and 2 diabetic patients with the absence or reduction of pancreatic β-cells. During the past few decades, the successful treatment of diabetes through transplantation of the whole pancreas or isolated islets has nearly been achieved. However, novel sources of pancreatic islets or insulin-producing cells are required to provide sufficient amounts of donor tissues. To overcome this limitation, the use of pancreatic progenitor cells is gaining more attention. In particular, pancreatic exocrine cells, such as duct epithelial cells and acinar cells, are attractive candidates for β-cell regeneration because of their differentiation potential and pancreatic lineage characteristics. It has been assumed that β-cell neogenesis from pancreatic progenitor cells could occur in pancreatic ducts in the postnatal stage. Several studies have shown that insulin-producing cells can arise in the duct tissue of the adult pancreas. Acinar cells also might have the potential to differentiate into insulin-producing cells. The present review summarizes recent progress in research on the transdifferentiation of pancreatic exocrine cells into insulin-producing cells, especially duct and acinar cells. PMID:27330712

  15. 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.

  16. 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.

  17. 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.

  18. 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

  19. Cell proliferation alterations in Chlorella cells under stress conditions

    International Nuclear Information System (INIS)

    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

  20. 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

  1. Regulation of Hematopoietic Stem Cells by Bone Marrow Stromal Cells

    OpenAIRE

    Anthony, Bryan; Link, Daniel C.

    2013-01-01

    Hematopoietic stem cells (HSCs) reside in specialized microenvironments (niches) in the bone marrow. The stem cell niche is thought to provide signals that support key HSC properties, including self-renewal capacity and long-term multilineage repopulation ability. The stromal cells that comprise the stem cell niche and the signals that they generate that support HSC function are the subjects of intense investigation. Here we review the complex and diverse stromal cell populations that reside ...

  2. Cell mechanics of alveolar epithelial cells (AECs) and macrophages (AMs).

    OpenAIRE

    Féréol, Sophie; Fodil, Redouane; Pelle, Gabriel; Louis, Bruno; Isabey, Daniel

    2008-01-01

    Cell mechanics provides an integrated view of many biological phenomena which are intimately related to cell structure and function. Because breathing constitutes a sustained motion synonymous with life, pulmonary cells are normally designed to support permanent cyclic stretch without breaking, while receiving mechanical cues from their environment. The authors study the mechanical responses of alveolar cells, namely epithelial cells and macrophages, exposed to well-controlled mechanical stre...

  3. Running with neighbors: coordinating cell migration and cell-cell adhesion.

    Science.gov (United States)

    Collins, Caitlin; Nelson, W James

    2015-10-01

    Coordinated movement of large groups of cells is required for many biological processes, such as gastrulation and wound healing. During collective cell migration, cell-cell and cell-extracellular matrix (ECM) adhesions must be integrated so that cells maintain strong interactions with neighboring cells and the underlying substratum. Initiation and maintenance of cadherin adhesions at cell-cell junctions and integrin-based cell-ECM adhesions require integration of mechanical cues, dynamic regulation of the actin cytoskeleton, and input from specific signaling cascades, including Rho family GTPases. Here, we summarize recent advances made in understanding the interplay between these pathways at cadherin-based and integrin-based adhesions during collective cell migration and highlight outstanding questions that remain in the field. PMID:26201843

  4. Innovative Tools and Technology for Analysis of Single Cells and Cell-Cell Interaction.

    Science.gov (United States)

    Konry, Tania; Sarkar, Saheli; Sabhachandani, Pooja; Cohen, Noa

    2016-07-11

    Heterogeneity in single-cell responses and intercellular interactions results from complex regulation of cell-intrinsic and environmental factors. Single-cell analysis allows not only detection of individual cellular characteristics but also correlation of genetic content with phenotypic traits in the same cell. Technological advances in micro- and nanofabrication have benefited single-cell analysis by allowing precise control of the localized microenvironment, cell manipulation, and sensitive detection capabilities. Additionally, microscale techniques permit rapid, high-throughput, multiparametric screening that has become essential for -omics research. This review highlights innovative applications of microscale platforms in genetic, proteomic, and metabolic detection in single cells; cell sorting strategies; and heterotypic cell-cell interaction. We discuss key design aspects of single-cell localization and isolation in microfluidic systems, dynamic and endpoint analyses, and approaches that integrate highly multiplexed detection of various intracellular species. PMID:26928209

  5. Innovative Tools and Technology for Analysis of Single Cells and Cell-Cell Interaction.

    Science.gov (United States)

    Konry, Tania; Sarkar, Saheli; Sabhachandani, Pooja; Cohen, Noa

    2016-07-11

    Heterogeneity in single-cell responses and intercellular interactions results from complex regulation of cell-intrinsic and environmental factors. Single-cell analysis allows not only detection of individual cellular characteristics but also correlation of genetic content with phenotypic traits in the same cell. Technological advances in micro- and nanofabrication have benefited single-cell analysis by allowing precise control of the localized microenvironment, cell manipulation, and sensitive detection capabilities. Additionally, microscale techniques permit rapid, high-throughput, multiparametric screening that has become essential for -omics research. This review highlights innovative applications of microscale platforms in genetic, proteomic, and metabolic detection in single cells; cell sorting strategies; and heterotypic cell-cell interaction. We discuss key design aspects of single-cell localization and isolation in microfluidic systems, dynamic and endpoint analyses, and approaches that integrate highly multiplexed detection of various intracellular species.

  6. 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.

  7. 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.

  8. 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.

  9. 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.

  10. Pituitary cells in space

    Science.gov (United States)

    Hymer, W. C.; Shellenberger, K.; Grindeland, R.

    1994-01-01

    Cells of the mammalian pituitary gland synthesize and secrete several protein hormones which regulate a number of organ systems throughout the body. These include the musculoskeletal, immune, vascular and endocrine systems. Since changes occur in these tissues as a result of spaceflight, and since pituitary growth hormone (GH) and prolactin (PRL) play a role in the control of these systems on earth, we have focused attention over the last 10 years on GH and PRL cell function during and after spaceflight. The cumulative results of 4 spaceflight missions and several mimicked microgravity experiments establish 1) that production and release of biologically active GH and PRL is repeatedly and significantly attenuated (usually >50%) and 2) that changes in cell morphology also occur. In this paper we describe our results within the framework of methodologies and approaches frequently used to study pituitary cell function on earth. In so doing we hope to develop future flight experiments aimed at uncovering possible microgravity 'sensing systems' within the pituitary cell.

  11. Limbal stem cell transplantation

    Directory of Open Access Journals (Sweden)

    Fernandes Merle

    2004-01-01

    Full Text Available The past two decades have witnessed remarkable progress in limbal stem cell transplantation. In addition to harvesting stem cells from a cadaver or a live related donor, it is now possible to cultivate limbal stem cells in vitro and then transplant them onto the recipient bed. A clear understanding of the basic disease pathology and a correct assessment of the extent of stem cell deficiency are essential. A holistic approach towards management of limbal stem cell deficiency is needed. This also includes management of the underlying systemic disease, ocular adnexal pathology and dry eye. Conjunctival limbal autografts from the healthy contralateral eye are performed for unilateral cases. In bilateral cases, tissue may be harvested from a cadaver or a living related donor; prolonged immunosuppression is needed to avoid allograft rejection in such cases. This review describes the surgical techniques, postoperative treatment regimes (including immunosuppression for allografts, the complications and their management. The short and long-term outcomes of the various modalities reported in the literature are also described.

  12. Seeing Cells on the Web

    Science.gov (United States)

    Liu, Dennis

    2007-01-01

    Cells are the fundamental unit of life and disease; therefore, many avenues of research converge on cells, making images of cells prominent in research and teaching. Much of the progress of modern biomedical science can be tied to advances in our ability to better visualize the functional morphology of cells, including higher resolution imaging,…

  13. 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

  14. Seventh Edition Fuel Cell Handbook

    Energy Technology Data Exchange (ETDEWEB)

    NETL

    2004-11-01

    Provides an overview of fuel cell technology and research projects. Discusses the basic workings of fuel cells and their system components, main fuel cell types, their characteristics, and their development status, as well as a discussion of potential fuel cell applications.

  15. The generation of sex cells

    OpenAIRE

    Deglincerti, Alessia; Brivanlou, Ali H.

    2015-01-01

    Primordial germ cells (PGCs) are the earliest population of germ cells established during embryonic development and constitute the beginning of the totipotent state. A recent study provides a new protocol for the efficient generation of PGC-like cells from human embryonic stem cells, providing an in vitro platform to study human PGC differentiation and specification.

  16. Stem Cell Transplants (For Parents)

    Science.gov (United States)

    ... Story" 5 Things to Know About Zika & Pregnancy Stem Cell Transplants KidsHealth > For Parents > Stem Cell Transplants Print A A A Text Size What's ... Recovery Coping en español Trasplantes de células madre Stem cells are cells in the body that have the ...

  17. Indeterminate cell histocytosis with naïve cells

    Directory of Open Access Journals (Sweden)

    Sheren F Younes

    2013-02-01

    Full Text Available Histiocytoses are a heterogeneous group of disorders characterized by proliferation and accumulation of cells of mononuclearmacrophage system and dendritic cells. Histiocytoses are categorized according to the cell of origin into Langerhans cell histiocytosis (LCH, Non Langerhans cell histiocytoses and indeterminate cell histiocytosis (ICH. ICH is an extraordinary rare neoplastic dendritic cell disorder that has poorly understood histogenesis and pathogenesis. It is characterized by a proliferation of dendritic cells, which mimic Langerhans cells immunophenotypically (positive for CD1a and S-100 protein, but lack Birbeck granules characteristic of Langerhans cells. Twenty-four year-old Egyptian male was presented with reddish brown chest wall nodule. Clinical, histopathological, immunohistochemical and ultrastructure features are typical for ICH. He was in a good state without any evidence of recurrence or metastasis after 24 months follow up. Peculiar histopathological features were detected in the present case. Many unidentified cells with Hematoxylin & Eosin Langerhans like features showed negative staining for S-100, CD1a, Langerin and CD68. In absence of cellular atypia and mitosis, the infiltrating cells showed epidermotropism that was reported once in ICH as well as neural and perineural invasion that were not previously reported. Therefore we prefer using a tentatively designated diagnosis; dendritic cell tumor, not otherwise specified or newly proposed diagnosis (Indeterminate cell histocytosis with naïve cells for the present case.

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

    Institute of Scientific and Technical Information of China (English)

    Medet; Jumabay; Kristina; I; Bostr?m

    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 suspensions and allowed to dedifferentiate into lipidfree multipotent cells, referred to as dedifferentiated fat(DFAT) cells. Compared to other adult stem cells, the DFAT cells have unique advantages in their abundance, ease of isolation and homogeneity. Under proper condition in vitro and in vivo, the DFAT cells have exhibited adipogenic, osteogenic, chondrogenic, cardiomyogenc, angiogenic, myogenic, and neurogenic potentials. In this review, we first discuss the phenomena of dedifferentiation and transdifferentiation of cells, and then dedifferentiation of adipocytes in particular. Understanding the dedifferentiation process itself may contribute to our knowledge of normal growth processes, as well as mechanisms of disease. Second, we highlight new developments in DFAT cell culture and summarize the current understanding of DFAT cell properties. The unique features of DFAT cells are promising for clinical applications such as tissue regeneration.

  19. New high-speed cell sorting methods for stem cell sorting and breast cancer cell purging

    Science.gov (United States)

    Leary, James F.; McLaughlin, Scott R.; Hokanson, James A.; Rosenblatt, Judah I.

    1998-04-01

    An important problem in clinical medicine is that of positively selecting hematopoietic stem cells or mobilized peripheral blood stem cells for autologous bone marrow transplantation while purging it of contaminating tumor cells. Since both the stem cells to be positively selected and the tumor cells to be purged are relatively rare cells, this poses special problems for their isolation in terms of purity and yield of stem cells, with a high penalty of misclassification for contaminating tumor cells. A model system of tumor cells spiked into bone marrow or blood cells was used to validate the system. Multiparameter data mixtures of human MCF-7 breast cancer cells and human peripheral blood or bone marrow cells were first analyzed by discriminant function analysis. Mathematical methods were developed to assess the relative probabilities of misclassification. Cell identification tags, implemented as additional correlated listmode parameters not used for these analyses, were used to uniquely identify each cell type and to compare classifier results. The performance of classifier systems was also assessed using ROC (`receiver operating characteristics') analysis. Then the classification system was implemented using lookup tables allowing for real-time (in this system approximately 625 microseconds) rapid separation of these cell types. Isolated cell types, purities and yields were assessed by single-cell PCR molecular characterizations.

  20. Enrichment and Function Research of Large Cell Lung Cancer Stem Cell-like Cells

    Directory of Open Access Journals (Sweden)

    Wenke YUE

    2011-06-01

    Full Text Available Background and objective There are no universal method to recognize and screen for lung cancer stem cell markers and indicators. Commonly used methods are flow Cytometry and learning from other cancer stem cell sorting tags to sort lung cancer stem cells. But this method has low specificity screening, the workload is huge. In this study, Serum-free suspension culture was used to enrich lung cancer stem cells, and explore method for lung cancer stem cell screening. Methods Human large lung cancer cell line-L9981 was cultured in serum-free and growth factors added medium, and spheres were obtained. Then the morphological differences of sphere cells and adherent L9981 cells cultured in serum-containing mediums are observed. Cell proliferation was analyzed by Vi-cell viability analyzer; invasion ability was tested by transwell assay; and in vivo tumorigenicity of the two groups of cells was studied in nude mouse. Results Compared with adherent L9981 cells cultured in serum-containing mediums, cells cultured in serum-free medium display sphere appearance. Doubling time of adherent cells and sphere cells are (56.05±1.95 h and (33.00±1.44 h respectively; Spheroid cells had higher invasion and tumorigenicity ability, 5 times and 20 times respectively, than adherent cells. Conclusion Suspension cultured L9981 in Serum-free medium could form spheroid populations. Cells in spheres had higher ability of invasion and Tumorigenicity than adherent L9981 cells. These results indicated spheroid L9981 cells contained enriched lung cancer stem cells, and Serum-free suspension culture can be a candidate method for enriching lung cancer stem cell.

  1. Proton exchange membrane fuel cells

    CERN Document Server

    Qi, Zhigang

    2013-01-01

    Preface Proton Exchange Membrane Fuel CellsFuel CellsTypes of Fuel CellsAdvantages of Fuel CellsProton Exchange Membrane Fuel CellsMembraneCatalystCatalyst LayerGas Diffusion MediumMicroporous LayerMembrane Electrode AssemblyPlateSingle CellStackSystemCell Voltage Monitoring Module (CVM)Fuel Supply Module (FSM)Air Supply Module (ASM)Exhaust Management Module (EMM)Heat Management Module (HMM)Water Management Module (WMM)Internal Power Supply Module (IPM)Power Conditioning Module (PCM)Communications Module (COM)Controls Module (CM)SummaryThermodynamics and KineticsTheoretical EfficiencyVoltagePo

  2. Cell-specific precursor processing

    DEFF Research Database (Denmark)

    Rehfeld, Jens F; Bundgaard, Jens R

    2010-01-01

    The singular gene for a peptide hormone is expressed not only in a specific endocrine cell type but also in other endocrine cells as well as in entirely different cells such as neurons, adipocytes, myocytes, immune cells, and cells of the sex-glands. The cellular expression pattern for each gene...... varies with development, time and species. Endocrine regulation is, however, based on the release of a given hormone from an endocrine cell to the general circulation from whose cappilaries the hormone reaches the specific target cell elsewhere in the body. The widespread expression of hormone genes in...... different cells and tissues therefore requires control of biogenesis and secretion in order to avoid interference with the function of a specific hormonal peptide from a particular endocrine cell. Several mechanisms are involved in such control, one of them being cell-specific processing of prohormones. The...

  3. Materials as stem cell regulators

    Science.gov (United States)

    Murphy, William L.; McDevitt, Todd C.; Engler, Adam J.

    2014-06-01

    The stem cell/material interface is a complex, dynamic microenvironment in which the cell and the material cooperatively dictate one another's fate: the cell by remodelling its surroundings, and the material through its inherent properties (such as adhesivity, stiffness, nanostructure or degradability). Stem cells in contact with materials are able to sense their properties, integrate cues via signal propagation and ultimately translate parallel signalling information into cell fate decisions. However, discovering the mechanisms by which stem cells respond to inherent material characteristics is challenging because of the highly complex, multicomponent signalling milieu present in the stem cell environment. In this Review, we discuss recent evidence that shows that inherent material properties may be engineered to dictate stem cell fate decisions, and overview a subset of the operative signal transduction mechanisms that have begun to emerge. Further developments in stem cell engineering and mechanotransduction are poised to have substantial implications for stem cell biology and regenerative medicine.

  4. Trophoblast lineage cells derived from human induced pluripotent stem cells

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Ying, E-mail: ying.chen@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Wang, Kai; Chandramouli, Gadisetti V.R. [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Knott, Jason G. [Developmental Epigenetics Laboratory, Department of Animal Science, Michigan State University (United States); Leach, Richard, E-mail: Richard.leach@hc.msu.edu [Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University, 333 Bostwick NE, Grand Rapids, MI 49503 (United States); Department of Obstetrics, Gynecology and Women’s Health, Spectrum Health Medical Group (United States)

    2013-07-12

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro.

  5. Trophoblast lineage cells derived from human induced pluripotent stem cells

    International Nuclear Information System (INIS)

    Highlights: •Epithelial-like phenotype of trophoblast lineage cells derived from human iPS cells. •Trophoblast lineage cells derived from human iPS cells exhibit trophoblast function. •Trophoblasts from iPS cells provides a proof-of-concept in regenerative medicine. -- Abstract: Background: During implantation, the blastocyst trophectoderm attaches to the endometrial epithelium and continues to differentiate into all trophoblast subtypes, which are the major components of a placenta. Aberrant trophoblast proliferation and differentiation are associated with placental diseases. However, due to ethical and practical issues, there is almost no available cell or tissue source to study the molecular mechanism of human trophoblast differentiation, which further becomes a barrier to the study of the pathogenesis of trophoblast-associated diseases of pregnancy. In this study, our goal was to generate a proof-of-concept model for deriving trophoblast lineage cells from induced pluripotency stem (iPS) cells from human fibroblasts. In future studies the generation of trophoblast lineage cells from iPS cells established from patient’s placenta will be extremely useful for studying the pathogenesis of individual trophoblast-associated diseases and for drug testing. Methods and results: Combining iPS cell technology with BMP4 induction, we derived trophoblast lineage cells from human iPS cells. The gene expression profile of these trophoblast lineage cells was distinct from fibroblasts and iPS cells. These cells expressed markers of human trophoblasts. Furthermore, when these cells were differentiated they exhibited invasive capacity and placental hormone secretive capacity, suggesting extravillous trophoblasts and syncytiotrophoblasts. Conclusion: Trophoblast lineage cells can be successfully derived from human iPS cells, which provide a proof-of-concept tool to recapitulate pathogenesis of patient placental trophoblasts in vitro

  6. Solid Oxide Electrolyser Cell

    DEFF Research Database (Denmark)

    Jensen, Søren Højgaard

    Solid oxide fuel cells (SOFCs) produced at Risø National Laboratory was tested as steam electrolysers under various current densities, operating temperatures and steam partial pressures. At 950 °C and a cell voltage of 1.48V the current density was -3.6A/cm2 with app. 30% H2 + 70% H2O in the inlet...... it is possible to achieve a production price of 0.7 US$/kg H2 with an electricity price of 1.3 US¢/kWh. The cell voltage was measured as function of time. In test ofabout two month of duration a long-term degradation was observed. At 850 °C, -0.5 A/cm2 with 50 vol% H2 the degradation rate was app. 20 mV/1000h...

  7. Fuel cell cogeneration

    Energy Technology Data Exchange (ETDEWEB)

    Wimer, J.G. [Dept. of Energy, Morgantown, WV (United States); Archer, D.

    1995-08-01

    The U.S. Department of Energy`s Morgantown Energy Technology Center (METC) sponsors the research and development of engineered systems which utilize domestic fuel supplies while achieving high standards of efficiency, economy, and environmental performance. Fuel cell systems are among the promising electric power generation systems that METC is currently developing. Buildings account for 36 percent of U.S. primary energy consumption. Cogeneration systems for commercial buildings represent an early market opportunity for fuel cells. Seventeen percent of all commercial buildings are office buildings, and large office buildings are projected to be one of the biggest, fastest-growing sectors in the commercial building cogeneration market. The main objective of this study is to explore the early market opportunity for fuel cells in large office buildings and determine the conditions in which they can compete with alternative systems. Some preliminary results and conclusions are presented, although the study is still in progress.

  8. Solar cell element

    Energy Technology Data Exchange (ETDEWEB)

    Nakano, Akihiko; Matsumoto, Hitoshi; Uda, Hiroshi; Komatsu, Yasumitsu; Ikegami, Kiyoharu.

    1989-05-18

    In the existing CdS/CdTe-based solar cell element, nothing is formed except the component effective for generating electromotive force and the components necessary for leading, collecting and extracting the generated electricity, hence even when the element shows deterioration of its performance during its usage, it has been difficult to analyze the above situation. In addition, it has also a defect that its characteristic such as the transfer efficiency in the neighborhood of its glass substrate in connection also with its manufacturing process. In order to solve the above problematical points, this invention proposes, with regard to a CdS-based solar cell element composed by forming a thin film on its substrate, to make a blank space on the above substrate and form thereon a thin film which composes the solar cell element concerned alone or in a piling up manner. 4 figs.

  9. ELECTROMOTIVE FORCE, EMF (CELLS)

    Energy Technology Data Exchange (ETDEWEB)

    Archer, M.D.; Feldberg, S.W.

    1998-09-16

    The voltage or electric potential difference across the terminals of a cell when no current is drawn from it. The emf of a cell is the sum of the electric potential differences (PDs) produced by a separation of charges (electrons or ions) that can occur at each phase boundary (or interface) in the cell. The magnitude of each PD depends on the chemical nature of the two contacting phases. Thus, at the interface between two different metals, some electrons will have moved from the metal with a higher free energy of electrons to the metal with a lower free energy of electrons. The resultant charge separation will produce a PD (just as charge separation produces a voltage across a capacitor) that, at equilibrium, exactly opposes further electron flow. Similarly, PDs can be produced when electrons partition across a metal/solution interface or metal/solid interface, and when ions partition across a solution/membrane/solution interface.

  10. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology (Finland). Dept. of Electrical and Communications Engineering

    1998-12-31

    Photovoltaic research began at the Electron Physics Laboratory of the Helsinki University of Tehnology in 1993, when the laboratory joined the national NEMO 2 research program. During the early stages of the photovoltaic research the main objective was to establish necessary measurement and characterisation routines, as well as to develop the fabrication process. The fabrication process development work has been supported by characterisation and theoretical modelling of the solar cells. Theoretical investigations have been concerned with systematic studies of solar cell parameters, such as diffusion lengths, surface recombination velocities and junction depths. The main result of the modelling and characterisation work is a method which is based on a Laplace transform of the so-called spatial collection efficiency function of the cell. The basic objective of the research has been to develop a fabrication process cheap enough to be suitable for commercial production

  11. Fuel cells in transportation

    Energy Technology Data Exchange (ETDEWEB)

    Erdmann, G. [Technische Univ., Berlin (Germany); Hoehlein, B. [Research Center Juelich (Germany)

    1996-12-01

    A promising new power source for electric drive systems is the fuel cell technology with hydrogen as energy input. The worldwide fuel cell development concentrates on basic research efforts aiming at improving this new technology and at developing applications that might reach market maturity in the very near future. Due to the progress achieved, the interest is now steadily turning to the development of overall systems such as demonstration plants for different purposes: electricity generation, drive systems for road vehicles, ships and railroads. This paper does not present results concerning the market potential of fuel cells in transportation but rather addresses some questions and reflections that are subject to further research of both engineers and economists. Some joint effort of this research will be conducted under the umbrella of the IEA Implementing Agreement 026 - Annex X, but there is a lot more to be done in this challenging but also promising fields. (EG) 18 refs.

  12. Welded solar cell interconnection

    Science.gov (United States)

    Stofel, E. J.; Browne, E. R.; Meese, R. A.; Vendura, G. J.

    1982-01-01

    The efficiency of the welding of solar-cell interconnects is compared with the efficiency of soldering such interconnects, and the cases in which welding may be superior are examined. Emphasis is placed on ultrasonic welding; attention is given to the solar-cell welding machine, the application of the welding process to different solar-cell configurations, producibility, and long-life performance of welded interconnects. Much of the present work has been directed toward providing increased confidence in the reliability of welding using conditions approximating those that would occur with large-scale array production. It is concluded that there is as yet insufficient data to determine which of three methods (soldering, parallel gap welding, and ultrasonic welding) provides the longest-duration solar panel life.

  13. Human leukaemic cells

    International Nuclear Information System (INIS)

    The results of the determination of trace elements in nucleic acids and histones in human leukaemic cells by activation analysis are reported. The Cr2+, Fe2+, Zn2+, Co2+ and Sb2+ content of DNA and RNA of leukaemic cells compared to that of lymphocytes from a patient with infectious mononucleosis or a normal donor are shown tabulated. Similar comparisons are shown for the same trace metal content of histones isolated from the same type of cells. It is felt that the results afford further interesting speculation that trace metals may be involved in the interactions between histones and DNA (especially at the binding sites of histones to DNA), which affect transcription characteristics. (U.K.)

  14. Stem cell therapy for diabetes

    OpenAIRE

    Lee, K. O.; Gan, S U; Calne, R Y

    2012-01-01

    Stem cell therapy holds immense promise for the treatment of patients with diabetes mellitus. Research on the ability of human embryonic stem cells to differentiate into islet cells has defined the developmental stages and transcription factors involved in this process. However, the clinical applications of human embryonic stem cells are limited by ethical concerns, as well as the potential for teratoma formation. As a consequence, alternative forms of stem cell therapies, such as induced plu...

  15. Radiosensitivity of mesothelioma cell lines

    International Nuclear Information System (INIS)

    The present study was carried out in order to examine the radiosensitivity of malignant pleural mesothelioma cell lines. Cell kinetics, radiation-induced delay of the cell cycle and DNA ploidy of the cell lines were also determined. For comparison an HeLa and a human foetal fibroblast cell line were simultaneously explored. Six previously cytogenetically and histologically characterized mesothelioma tumor cell lines were applied. A rapid tiazolyl blue microtiter (MTT) assay was used to analyze radiosensitivity and cell kinetics and DNA ploidy of the cultured cells were determined by flow cytometry. The survival fraction after a dose of 2 Gy (SF2), parameters α and β of the linear quadratic model (LQ-model) and mean inactivation dose (DMID) were also estimated. The DNA index of four cell lines equaled 1.0 and two cell lines equaled 1.5 and 1.6. Different mesothelioma cell lines showed a great variation in radiosensitivity. Mean survival fraction after a radiation dose of 2 Gy (SF2) was 0.60 and ranged from 0.36 to 0.81 and mean α value was 0.26 (range 0.48-0.083). The SF2 of the most sensitive diploid mesothelioma cell line was 0.36: Less than that of the foetal fibroblast cell line (0.49). The survival fractions (0.81 and 0.74) of the two most resistant cell lines, which also were aneuploid, were equal to that of the HeLa cell line (0.78). The α/β ratios of the most sensitive cell lines were almost an order of magnitude greater than those of the two most resistant cell lines. Radiation-induced delay of the most resistant aneuploid cell line was similar to that of HeLa cells but in the most sensitive (diploid cells) there was practically no entry into the G1 phase following the 2 Gy radiation dose during 36 h. (orig.)

  16. Stem cell organization in Arabidopsis

    OpenAIRE

    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 meristems stay active throughout plant-life. Specification of stem cells occurs very early during development of the emrbyo and they are maintained during later stages. The Arabidopsis embryo is a hig...

  17. Dense pattern optical multipass cell

    Science.gov (United States)

    Silver, Joel A [Santa Fe, NM

    2009-01-13

    A multiple pass optical cell and method comprising providing a pair of opposed cylindrical mirrors having curved axes with substantially equal focal lengths, positioning an entrance hole for introducing light into the cell and an exit hole for extracting light from the cell, wherein the entrance hole and exit hole are coextensive or non-coextensive, introducing light into the cell through the entrance hole, and extracting light from the cell through the exit hole.

  18. Characterization of cells in cork

    Science.gov (United States)

    Pina, P.; Fortes, M. A.

    1996-09-01

    Various topological and metric properties of the cells in the phelogen of the cork oak have been measured in tangential sections of cork by image analysis methods. These include the fractions 0022-3727/29/9/041/img5 of cells with i sides (i-cells), the fractions 0022-3727/29/9/041/img6 of adjacencies between i- and k-cells and various distributions of cell areas in relation to topology.

  19. NK cell-released exosomes

    OpenAIRE

    Fais, Stefano

    2013-01-01

    We have recently reported that human natural killer (NK) cells release exosomes that express both NK-cell markers and cytotoxic molecules. Similar results were obtained with circulating exosomes from human healthy donors. Both NK-cell derived and circulating exosomes exerted a full functional activity and killed both tumor and activated immune cells. These findings indicate that NK-cell derived exosomes might constitute a new promising therapeutic tool.

  20. Photoelectrochemical cell with nondissolving anode

    Science.gov (United States)

    Ellis, A. B.; Kaiser, S. W.; Wrighton, M. S.

    1980-01-01

    Improved electrolytic cells have efficiencies comparable to those of best silicon solar cells but are potentially less expensive to manufacture. Cells consist of light-sensitive n-type semiconductor anode and metallic cathode immersed in electrolytic solution. Reversible redox cells produce no chemical change in electrolyte and stabilize anode against dissolving. Cell can produce more than 500 mW of power per square centimeter of anode area at output voltage of 0.4 V.

  1. Interband Cascade Photovoltaic Cells

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Rui Q. [Univ. of Oklahoma, Norman, OK (United States); Santos, Michael B. [Univ. of Oklahoma, Norman, OK (United States); Johnson, Matthew B. [Univ. of Oklahoma, Norman, OK (United States)

    2014-09-24

    In this project, we are performing basic and applied research to systematically investigate our newly proposed interband cascade (IC) photovoltaic (PV) cells [1]. These cells follow from the great success of infrared IC lasers [2-3] that pioneered the use of quantum-engineered IC structures. This quantum-engineered approach will enable PV cells to efficiently convert infrared radiation from the sun or other heat source, to electricity. Such cells will have important applications for more efficient use of solar energy, waste-heat recovery, and power beaming in combination with mid-infrared lasers. The objectives of our investigations are to: achieve extensive understanding of the fundamental aspects of the proposed PV structures, develop the necessary knowledge for making such IC PV cells, and demonstrate prototype working PV cells. This research will focus on IC PV structures and their segments for utilizing infrared radiation with wavelengths from 2 to 5 μm, a range well suited for emission by heat sources (1,000-2,000 K) that are widely available from combustion systems. The long-term goal of this project is to push PV technology to longer wavelengths, allowing for relatively low-temperature thermal sources. Our investigations address material quality, electrical and optical properties, and their interplay for the different regions of an IC PV structure. The tasks involve: design, modeling and optimization of IC PV structures, molecular beam epitaxial growth of PV structures and relevant segments, material characterization, prototype device fabrication and testing. At the end of this program, we expect to generate new cutting-edge knowledge in the design and understanding of quantum-engineered semiconductor structures, and demonstrate the concepts for IC PV devices with high conversion efficiencies.

  2. The Stem Cell Conundrum

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ At the beginning of this year, Kelly Reynolds,a US-national diagnosed with amyotrophic lateral sclerosis (ALS), became the one of the latest overseas patient to undergo stem cell treatment at the Nanshan Hospital in Shenzhen.Confined to a wheelchair and with limited use of his hands,the 39-year old received four fetal stem cell injections over a three-week period. So far,the results have been positive and Reynolds, acording to his personal blog page, is upbeat about the long-term benefits.

  3. Optoelectronics of solar cells

    CERN Document Server

    Smestad, Greg P

    2002-01-01

    With concerns about worldwide environmental security, global warming, and climate change due to emissions of carbon dioxide from the burning of fossil fuels, it is desirable to have a wide range of energy technologies in a nation's portfolio. Photovoltaics, or solar cells, are a viable option as a nonpolluting renewable energy source. This text is designed to be an overview of photovoltaic solar cells for those in the fields of optics and optical engineering, as well as those who are interested in energy policy, economics, and the requirements for efficient photo-to-electric energy conversion.

  4. Rectenna solar cells

    CERN Document Server

    Moddel, Garret

    2013-01-01

    Rectenna Solar Cells discusses antenna-coupled diode solar cells, an emerging technology that has the potential to provide ultra-high efficiency, low-cost solar energy conversion. This book will provide an overview of solar rectennas, and provide thorough descriptions of the two main components: the diode, and the optical antenna. The editors discuss the science, design, modeling, and manufacturing of the antennas coupled with the diodes. The book will provide concepts to understanding the challenges, fabrication technologies, and materials required to develop rectenna structures. Written by e

  5. Silicon heterojunction solar cells

    CERN Document Server

    Fahrner, W R; Neitzert, H C

    2006-01-01

    The world of today must face up to two contradictory energy problems: on the one hand, there is the sharply growing consumer demand in countries such as China and India. On the other hand, natural resources are dwindling. Moreover, many of those countries which still possess substantial gas and oil supplies are politically unstable. As a result, renewable natural energy sources have received great attention. Among these, solar-cell technology is one of the most promising candidates. However, there still remains the problem of the manufacturing costs of such cells. Many attempts have been made

  6. Granular Cell Schwannoma

    Directory of Open Access Journals (Sweden)

    Dheepa R

    2004-01-01

    Full Text Available An 11 year old female child had a small painful spot over the scalp of 4 months duration. Earlier, she had undergone a local excision for a similar problem, but it had recurred at the same site after a few months. Examination revealed a skin colored sessile tender firm papule of 3 mm size on the right parietal region. Excision biopsy showed broad fascicles of tumor cells with eosinopilic cytoplasmic granules infiltrating the dermis amongst the collagen bundles, which was consistent with granular cell schwannoma.

  7. Characterization of solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Haerkoenen, J.; Tuominen, E.; Nybergh, K.; Ezer, Y.; Yli-Koski, M.; Sinkkonen, J. [Helsinki Univ. of Technology, Otaniemi (Finland). Dept. of Electrical and Communications Engineering

    1998-10-01

    Photovoltaic research in the Electron Physics Laboratory started in 1993, when laboratory joined the national TEKES/NEMO 2 research program. Since the beginning of the project, characterization as well as experimentally orientated development of the fabrication process of the solar cells were carried out parallery. The process development research started by the initiatives of the Finnish industry. At the moment a large amount of the laboratory personnel works on solar cell research and the financing comes mainly from external projects. The funding for the research has come from TEKES, Ministry of Education, Finnish Academy, GETA graduate school, special equipment grants of the university, and from the laboratory

  8. Clear cell chondrosarcoma

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, R.; David, R.; Cierney, G. III

    1985-01-01

    The clinical, radiologic, and histopathologic features of three cases of clear cell chondrosarcoma are described. On radiographs, this rather benign-appearing tumor resembles a chondroblastoma when it occurs at the end of a long bone, and may occasionally show a calcified matrix. However, it has distinctive tumor cells with a centrally placed vesicular nucleus surrounded by clear cytoplasm. The lesion has a low-grade malignancy and is amenable to en bloc surgical resection, which results in a much better prognosis than that of conventional chondrosarcoma.

  9. Epidermal stem cell dynamics

    OpenAIRE

    Sieber-Blum, Maya

    2011-01-01

    Wong and Reiter have explored the possibility that hair follicle stem cells can give rise to basal cell carcinoma (BCC). They expressed in mice an inducible human BCC-derived oncogenic allele of Smoothened, SmoM2, under the control of either the cytokeratin 14 (K14) or cytokeratin 15 (K15) promoter. Smoothened encodes a G-protein-coupled receptor protein in the hedgehog pathway, the misregulation of which is implicated in BCC and other human cancers. Chronic injury is thought to be a contribu...

  10. Microfluidic Cell Culture Device

    Science.gov (United States)

    Takayama, Shuichi (Inventor); Cabrera, Lourdes Marcella (Inventor); Heo, Yun Seok (Inventor); Smith, Gary Daniel (Inventor)

    2014-01-01

    Microfluidic devices for cell culturing and methods for using the same are disclosed. One device includes a substrate and membrane. The substrate includes a reservoir in fluid communication with a passage. A bio-compatible fluid may be added to the reservoir and passage. The reservoir is configured to receive and retain at least a portion of a cell mass. The membrane acts as a barrier to evaporation of the bio-compatible fluid from the passage. A cover fluid may be added to cover the bio-compatible fluid to prevent evaporation of the bio-compatible fluid.

  11. Carbon Nanotube Solar Cells

    OpenAIRE

    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 fabr...

  12. Fuel cell engineering

    CERN Document Server

    Sundmacher

    2012-01-01

    Fuel cells are attractive electrochemical energy converters featuring potentially very high thermodynamic efficiency factors. The focus of this volume of Advances in Chemical Engineering is on quantitative approaches, particularly based on chemical engineering principles, to analyze, control and optimize the steady state and dynamic behavior of low and high temperature fuel cells (PEMFC, DMFC, SOFC) to be applied in mobile and stationary systems. * Updates and informs the reader on the latest research findings using original reviews * Written by leading industry experts and scholars * Review

  13. Development of neural precursor cells from mouse embryonic stem cells

    Institute of Scientific and Technical Information of China (English)

    WU Xuan; LI Hai-di; Li Shu-nong; XU Hai-wei; XU Ling

    2001-01-01

    Objective: To explore the serum-free culture conditions for differentiating mouse embryonic stem cells (ES cells)into neural precursor cells (NPC) and compare the effects of human embryonic fibroblasts (HEF) as the feeder layer of ES with that of mouse embryonic fibroblasts (MEF)in vitro. Methods: Mouse ES cells were cultured in or not in feeder layer cells medium containing or not leukemia inhibitory factor to suppress their differentiation. Immunocytochemical method was used to identify NPC by detecting nestin antigen and alkaline phosphatase. Results: The ES cells cultured in HEF were positive to alkaline phosphatase. Serum-free medium allowed the differentiation of ES cells into NPC. Conclusion:HEF could replace MEF and keep the undifferentiated condition of ES cells with more benefits. NPC of high purity could be cultured from ES cells by serum-free culture method.

  14. Industrial n-type solar cells with >20% cell efficiency

    Energy Technology Data Exchange (ETDEWEB)

    Romijn, I.G.; Anker, J.; Burgers, A.R.; Gutjahr, A.; Koppes, M.; Kossen, E.J.; Lamers, M.W.P.E.; Heurtault, Benoit; Saynova-Oosterling, D.S.; Tool, C.J.J. [ECN Solar Energy, Petten (Netherlands)

    2013-03-15

    To realize high efficiencies at low costs, ECN has developed the n-Pasha solar cell concept. The n-Pasha cell concept is a bifacial solar cell concept on n-Cz base material, with which average efficiencies of above 20% have been demonstrated. In this paper recent developments at ECN to improve the cost of ownership (lower Euro/Wp) of the n-Pasha cell concept are discussed. Two main drivers for the manufacturing costs of n-type solar cells are addressed: the n-type Cz silicon material and the silver consumption. We show that a large resistivity range between 2 and 8 cm can be tolerated for high cell efficiency, and that the costs due to the silver metallization can be significantly reduced while increasing the solar cell efficiency. Combining the improved efficiency and cost reduction makes the n-Pasha cell concept a very cost effective solution to manufacture high efficient solar cells and modules.

  15. Colorectal Cancer Stem Cells and Cell Death

    Energy Technology Data Exchange (ETDEWEB)

    Catalano, Veronica [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Gaggianesi, Miriam [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Department of Cellular and Molecular Oncology, IRCCS Fondazione Salvatore Maugeri, Via Salvatore Maugeri, 27100 Pavia, PV (Italy); Spina, Valentina; Iovino, Flora [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Dieli, Francesco [Departement of Biopathology and Medicine Biotechnologies, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Stassi, Giorgio, E-mail: giorgio.stassi@unipa.it [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy); Department of Cellular and Molecular Oncology, IRCCS Fondazione Salvatore Maugeri, Via Salvatore Maugeri, 27100 Pavia, PV (Italy); Todaro, Matilde [Department of Surgical and Oncological Sciences, University of Palermo, Via Liborio Giuffrè 5, 90127 Palermo, PA (Italy)

    2011-04-11

    Nowadays it is reported that, similarly to other solid tumors, colorectal cancer is sustained by a rare subset of cancer stem–like cells (CSCs), which survive conventional anticancer treatments, thanks to efficient mechanisms allowing escape from apoptosis, triggering tumor recurrence. To improve patient outcomes, conventional anticancer therapies have to be replaced with specific approaches targeting CSCs. In this review we provide strong support that BMP4 is an innovative therapeutic approach to prevent colon cancer growth increasing differentiation markers expression and apoptosis. Recent data suggest that in colorectal CSCs, protection from apoptosis is achieved by interleukin-4 (IL-4) autocrine production through upregulation of antiapoptotic mediators, including survivin. Consequently, IL-4 neutralization could deregulate survivin expression and localization inducing chemosensitivity of the colon CSCs pool.

  16. Fuel Cell Testing - Degradation of Fuel Cells and its Impact on Fuel Cell Applications

    OpenAIRE

    Pfrang, Andreas

    2008-01-01

    Fuel cells are expected to play a major role in the future energy supply, especially polymer electrolyte membrane fuel cells could become an integral part in future cars. Reduction of degradation of fuel cell performance while keeping fuel cell cost under control is the key for an introduction into mass markets.

  17. Cell Cycle Related Differentiation of Bone Marrow Cells into Lung Cells

    Energy Technology Data Exchange (ETDEWEB)

    Dooner, Mark; Aliotta, Jason M.; Pimental, Jeffrey; Dooner, Gerri J.; Abedi, Mehrdad; Colvin, Gerald; Liu, Qin; Weier, Heinz-Ulli; Dooner, Mark S.; Quesenberry, Peter J.

    2007-12-31

    Green-fluorescent protein (GFP) labeled marrow cells transplanted into lethally irradiated mice can be detected in the lungs of transplanted mice and have been shown to express lung specific proteins while lacking the expression of hematopoietic markers. We have studied marrow cells induced to transit cell cycle by exposure to IL-3, IL-6, IL-11 and steel factor at different times of culture corresponding to different phases of cell cycle. We have found that marrow cells at the G1/S interface have a 3-fold increase in cells which assume a lung phenotype and that this increase is no longer seen in late S/G2. These cells have been characterized as GFP{sup +} CD45{sup -} and GFP{sup +} cytokeratin{sup +}. Thus marrow cells with the capacity to convert into cells with a lung phenotype after transplantation show a reversible increase with cytokine induced cell cycle transit. Previous studies have shown the phenotype of bone marrow stem cells fluctuates reversibly as these cells traverse cell cycle, leading to a continuum model of stem cell regulation. The present studies indicate that marrow stem cell production of nonhematopoietic cells also fluctuates on a continuum.

  18. Sertoli cells maintain Leydig cell number and peritubular myoid cell activity in the adult mouse testis.

    Directory of Open Access Journals (Sweden)

    Diane Rebourcet

    Full Text Available The Sertoli cells are critical regulators of testis differentiation and development. In the adult, however, their known function is restricted largely to maintenance of spermatogenesis. To determine whether the Sertoli cells regulate other aspects of adult testis biology we have used a novel transgenic mouse model in which Amh-Cre induces expression of the receptor for Diphtheria toxin (iDTR specifically within Sertoli cells. This causes controlled, cell-specific and acute ablation of the Sertoli cell population in the adult animal following Diphtheria toxin injection. Results show that Sertoli cell ablation leads to rapid loss of all germ cell populations. In addition, adult Leydig cell numbers decline by 75% with the remaining cells concentrated around the rete and in the sub-capsular region. In the absence of Sertoli cells, peritubular myoid cell activity is reduced but the cells retain an ability to exclude immune cells from the seminiferous tubules. These data demonstrate that, in addition to support of spermatogenesis, Sertoli cells are required in the adult testis both for retention of the normal adult Leydig cell population and for support of normal peritubular myoid cell function. This has implications for our understanding of male reproductive disorders and wider androgen-related conditions affecting male health.

  19. IARS2 silencing induces non-small cell lung cancer cells proliferation inhibition, cell cycle arrest and promotes cell apoptosis.

    Science.gov (United States)

    Yin, J; Liu, W; Li, R; Liu, J; Zhang, Y; Tang, W; Wang, K

    2016-01-01

    The purpose of this study was to investigate the potential role of Ileucyl-tRNA synthetase (IARS2) silencing in non-small cell lung cancer (NSCLC). The silencing of IARS2 in H1299 cells and A549 cells were performed by lentivirus encoding shRNAs. The efficiency of IARS2 silencing was detected by quantitative real time PCR and western blot. The effects of IARS2 silencing on cell growth, cell apoptosis, cell cycle and cell colony formation ability were assessed by cells counting, MTT assay, flow cytometer analysis and soft agar colony formation assay, respectively. Compared with negative control group, IARS2 was significantly knockdown by transfection with lentivirus encoding shRNA of IARS2. The IARS2 silencing significantly inhibited the cells proliferation and cells colony formation ability, induced cell cycle arrest at G1/S phase and promoted cell apoptosis. IARS2 silencing induced NSCLC cells growth inhibition, cell cycle arrest and promoted cell apoptosis. These results suggest that IARS2 may be a novel target for the treatment of NSCLC. PMID:26639235

  20. Improved micromorph tandem cell performance through enhanced top cell currents

    Energy Technology Data Exchange (ETDEWEB)

    Platz, R.; Vaucher, N.P.; Fischer, D.; Meier, J.; Shah, A. [Univ. de Neuchatel (Switzerland). Inst. de Microtechnique

    1997-12-31

    Two approaches to increasing the current in the amorphous silicon top cell of an amorphous silicon/microcrystalline silicon (a-Si:H/{micro}c-Si:H) tandem cell are presented. The goal is to raise the stabilized efficiency of such cells. The deposition of the amorphous top cell at higher than standard substrate temperature is shown to reduce the optical gap of the i-layer and to increase the current which is generated with a given i-layer thickness. Furthermore, a selectively reflecting ZnO interface layer between the component cells is presented as a viable tool for enhancing the current generation in the top cell by selective reflection of light. The authors present a micromorph tandem cell containing the amorphous top cell deposited at high substrate temperature, and additionally the ZnO mirror layer. A top cell thickness of 150 nm is shown to be sufficient to provide a current density of 13mA/cm{sup 2} in the top cell. Finally, the influence of such thin top cells on the stabilized efficiency of the tandem cell is investigated by experiment and by means of semi-empirical modeling. Model and experiment confirm that such reduced-gap top cells, together with current enhancement due to the mirror layer, have a high potential for improving the stabilized efficiency of micromorph tandem cells.