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Sample records for human cells electronic

  1. Induction of retrovirus particles in human testicular tumor (Tera-1) cell cultures: an electron microscopic study.

    Science.gov (United States)

    Bronson, D L; Fraley, E E; Fogh, J; Kalter, S S

    1979-08-01

    The Tera-1 and Tera-2 cell lines, established from germ-cell tumors of the human testis, were examined by electron microscopy for particles with the morphology of retroviruses. Extracellular and budding particles were observed at low frequencies only in cultures of Tera-1 cells that had been treated with 5-iodo-2'-deoxyuridine and dexamethasone. No particles were detected in untreated cultures of Tera-1 cells or in any preparations of Tera-2 cells.

  2. Radiotoxicity induced by Auger electron emitters in human osteosarcoma cell line using comet assay

    Institute of Scientific and Technical Information of China (English)

    XU Yu-Jie; LI Qing-Nuan; ZHU Ran; ZHU Ben-Xing; ZHANG Yong-Ping; ZHANG Xiao-Dong; FAN Wo; HONG Cheng-Jiao; LI Wen-Xin

    2003-01-01

    The comet assay (single cell gel electrophoresis assay) was used to evaluate the radiotoxicity of Augerelectron emitters in the human osteosarcoma cell line (HOS-8603). After internal exposure to 67Ga-EDTMP, the sar-coma cell has been injured severely. The comet length was longer along with the increase of dose, the appearance ofcomet tail was different from that with respect to the 60Co γ-ray irradiation. DNA damage of cell was mainly due tothe radiation effect of Auger electrons. The 67Ga may be a therapeutic radionuclide with good prospect for tumortreatment and palliation of bone pain induced by metastasis.

  3. Hepatic progenitor cells in human liver cirrhosis:Immunohistochemical,electron microscopic and immunofluorencence confocal microscopic findings

    Institute of Scientific and Technical Information of China (English)

    Jia-Cheng Xiao; Xiao-Long Jin; Peter Ruck; Anne Adam; Edwin Kaiserling

    2004-01-01

    AIM: To investigate whether hepatic progenitor cells (HPC),that reveal the features of oval cells in rodents and small epithelial cells (SEC) in certain human liver disease, were also found in human liver cirrhosis (HLC).METHODS: Surgical liver specimens from 20 cases of hepatitis B virus-positive HLC (15 cases containing hepatocellular carcinoma) were investigated by light microscopic immunohistochemistry (LM-IHC). Among them specimens from 15 cases were investigated by electron microscopy (EM)and those from 5 cases by immunofluorencence confocal laser scanning microscopy (ICLSM). Antibodies against cytokeratin 7 and albumin were used and single and/or double labelling were performed respectively.RESULTS: LM-IHC showed that at the margins of regenerating nodules and in the fibrous septae, a small number of cells in the proliferating bile ductules were positive for CK7 and albumin. At the EM level these HPC were morphologically similar to the SEC described previously, and also similar to the oval cells seen in experimental hepatocarcinogenesis.They were characterized by their small size, oval shape, a high nucleus/cytoplasm ratio, a low organelle content in cytoplasm, and existence of tonofilaments and intercellular junctions. ICLSM revealed that HPC expressed both cytokeratin 7 and albumin.CONCLUSION: HPC with ultrastructural and immunophenotypical features of oval cells, i.e., hepatic stem cell-like cells as noted in other liver diseases, were found in HLC. These findings further support the hypothesis that bipotent hepatic stem cells, that may give rise to biliary epithelial cells and hepatocytes, exist in human livers.

  4. Scanning electron microscopic study of human neuroblastoma cells affected with Naegleria fowleri Thai strains.

    Science.gov (United States)

    Tiewcharoen, Supathra; Rabablert, Jundee; Chetanachan, Pruksawan; Junnu, Virach; Worawirounwong, Dusit; Malainual, Nat

    2008-10-01

    In order to understand the pathogenesis of Naegleria fowleri in primary amoebic meningoencephalitis, the human neuroblastoma (SK-N-MC) and African green monkey kidney (Vero) cells were studied in vitro. Amoeba suspension in cell-culture medium was added to the confluent monolayer of SK-N-MC and Vero cells. The cytopathic activity of N. fowleri trophozoites in co-culture system was elucidated by scanning electron microscope at 3, 6, 9, 12, and 24 h. Two strains of N. fowleri displayed well-organized vigorous pseudopods in Nelson's medium at 37 degrees C. In co-culture, the target monolayer cells were damaged by two mechanisms, phagocytosis by vigorous pseudopods and engulfment by sucker-like apparatus. N. fowleri trophozoites produced amoebostomes only in co-culture with SK-N-MC cells. In contrast, we could not find such apparatus in the co-culture with Vero cells. The complete destruction time (100%) at 1:1 amoeba/cells ratio of SK-N-MC cells (1 day) was shorter than the Vero cells (12 days). In conclusion, SK-N-MC cells were confirmed to be a target model for studying neuropathogenesis of primary amoebic meningoencephalitis.

  5. A direct electron transfer-based glucose/oxygen biofuel cell operating in human serum

    Energy Technology Data Exchange (ETDEWEB)

    Coman, V.; Gorton, L. [Department of Analytical Chemistry/Biochemistry, Lund University, 22100 Lund (Sweden); Ludwig, R. [Research Centre Applied Biocatalysis, 8010 Graz (Austria); Department of Food Sciences and Technology, BOKU-University of Natural Resources and Applied Life Sciences, 1190 Wien (Austria); Harreither, W.; Haltrich, D. [Department of Food Sciences and Technology, BOKU-University of Natural Resources and Applied Life Sciences, 1190 Wien (Austria); Ruzgas, T. [Biomedical Laboratory Science, Health and Society, Malmoe University, 20506 Malmoe (Sweden); Laboratory of Chemical Enzymology, A.N. Bach Institute of Biochemistry, 119071 Moscow (Russian Federation); Shleev, S.

    2010-02-15

    We report on the fabrication and characterisation of the very first direct electron transfer-based glucose/oxygen biofuel cell (BFC) operating in neutral glucose-containing buffer and human serum. Corynascus thermophilus cellobiose dehydrogenase and Myrothecium verrucaria bilirubin oxidase were used as anodic and cathodic bioelements, respectively. The following characteristics of the mediator-, separator- and membrane-less, a priori, non-toxic and simple miniature BFC, was obtained: an open-circuit voltage of 0.62 and 0.58 V, a maximum power density of ca. 3 and 4 {mu}W cm{sup -2} at 0.37 and 0.19 V of cell voltage, in phosphate buffer and human serum, respectively. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  6. The sinusoidal lining cells in "normal" human liver. A scanning electron microscopic investigation

    DEFF Research Database (Denmark)

    Horn, T; Henriksen, Jens Henrik Sahl; Christoffersen, P

    1986-01-01

    The scanning electron microscopic was used to study the fenestrations of human liver sinusoids. Thirteen biopsies, where light microscopy and transmission electron microscopy revealed normal sinusoidal architecture, were investigated. The number of fenestrae was calculated in acinar zone 3...

  7. Decellularized human Schneiderian membrane: electron microscopic study as a bioscaffold and preliminary cell seeding.

    Science.gov (United States)

    Rahpeyma, Amin; Khajehahmadi, Saeedeh; Khalife, Hussein H

    2014-12-01

    Perforation of maxillary sinus mucous membrane is one of the most prevalent complications during open sinus lift surgery. Moreover, such complication can usually be managed by an absorbable membrane. As far as absorbable membranes are concerned, decellularized maxillary sinus mucous membrane, which is an extracellular matrix, can be used as a biologic scaffold and an insulating membrane in sinus lifting surgery. The decellularization process of the maxillary sinus membrane was performed by means of physical and chemical procedures (liquid nitrogen and sodium dodecyl sulfate). Then this membrane was used as a bioscaffold for culturing with adult mesenchymal stem cells, which were derived from adipose tissue. Histologic evaluation of the decellularized scaffold revealed that cells of the Schneiderian membrane were compatibly removed via SDS 1%. Moreover, the scan with electron microscope (S6N - Leo vp1450, Germany) of the scaffold indicated that the collagen fibers of the decellularized maxillary sinus membrane were intact. Furthermore, the culture studies carried out showed that this scaffold supported cell seeding. The decellularized human maxillary Schneiderian membrane has a 3D structure similar to that of the extracellular matrix of human normal tissues. As a matter of fact, it can be used as a bioscaffold to support cell seeding. Copyright © 2014 Elsevier GmbH. All rights reserved.

  8. Electronic cigarette liquid increases inflammation and virus infection in primary human airway epithelial cells.

    Directory of Open Access Journals (Sweden)

    Qun Wu

    Full Text Available The use of electronic cigarettes (e-cigarettes is rapidly increasing in the United States, especially among young people since e-cigarettes have been perceived as a safer alternative to conventional tobacco cigarettes. However, the scientific evidence regarding the human health effects of e-cigarettes on the lung is extremely limited. The major goal of our current study is to determine if e-cigarette use alters human young subject airway epithelial functions such as inflammatory response and innate immune defense against respiratory viral (i.e., human rhinovirus, HRV infection.We examined the effects of e-cigarette liquid (e-liquid on pro-inflammatory cytokine (e.g., IL-6 production, HRV infection and host defense molecules (e.g., short palate, lung, and nasal epithelium clone 1, SPLUNC1 in primary human airway epithelial cells from young healthy non-smokers. Additionally, we examined the role of SPLUNC1 in lung defense against HRV infection using a SPLUNC1 knockout mouse model. We found that nicotine-free e-liquid promoted IL-6 production and HRV infection. Addition of nicotine into e-liquid further amplified the effects of nicotine-free e-liquid. Moreover, SPLUNC1 deficiency in mice significantly increased lung HRV loads. E-liquid inhibited SPLUNC1 expression in primary human airway epithelial cells. These findings strongly suggest the deleterious health effects of e-cigarettes in the airways of young people. Our data will guide future studies to evaluate the impact of e-cigarettes on lung health in human populations, and help inform the public about potential health risks of e-cigarettes.

  9. Electronic cigarette liquid increases inflammation and virus infection in primary human airway epithelial cells.

    Science.gov (United States)

    Wu, Qun; Jiang, Di; Minor, Maisha; Chu, Hong Wei

    2014-01-01

    The use of electronic cigarettes (e-cigarettes) is rapidly increasing in the United States, especially among young people since e-cigarettes have been perceived as a safer alternative to conventional tobacco cigarettes. However, the scientific evidence regarding the human health effects of e-cigarettes on the lung is extremely limited. The major goal of our current study is to determine if e-cigarette use alters human young subject airway epithelial functions such as inflammatory response and innate immune defense against respiratory viral (i.e., human rhinovirus, HRV) infection. We examined the effects of e-cigarette liquid (e-liquid) on pro-inflammatory cytokine (e.g., IL-6) production, HRV infection and host defense molecules (e.g., short palate, lung, and nasal epithelium clone 1, SPLUNC1) in primary human airway epithelial cells from young healthy non-smokers. Additionally, we examined the role of SPLUNC1 in lung defense against HRV infection using a SPLUNC1 knockout mouse model. We found that nicotine-free e-liquid promoted IL-6 production and HRV infection. Addition of nicotine into e-liquid further amplified the effects of nicotine-free e-liquid. Moreover, SPLUNC1 deficiency in mice significantly increased lung HRV loads. E-liquid inhibited SPLUNC1 expression in primary human airway epithelial cells. These findings strongly suggest the deleterious health effects of e-cigarettes in the airways of young people. Our data will guide future studies to evaluate the impact of e-cigarettes on lung health in human populations, and help inform the public about potential health risks of e-cigarettes.

  10. Light and electron microscopic study of epithelial cells from the human oviduct and uterus subcultured on extracellular matrix gel.

    Science.gov (United States)

    Eslaminejad, Mohamadreza Baghaban; Valojerdi, Mojtaba Rezazadeh; Ashtiani, Saeed Kazemi; Eftekhari-Yazdi, Poopak

    2007-06-01

    To investigate the structure of epithelial cells from the human oviduct and uterus on extracellular matrix (ECM) gel in the first passage. Human oviducts and endometrial tissues were obtained from patients undergoing total hysterectomy; the epithelial cells, having been isolated by enzyme digestion, were cultured on polystyrene plastic surfaces. The epithelial nature of the cells was confirmed by immunocytochemistry, and their morphology was examined by microscopy. Cells of an epithelial nature were then trypsinized and cultured on an ECM gel-coated filter insert for 5 days. The cells, in parallel with the tissues, were subsequently prepared for transmission electron microscopy. Plastic-cultured cells had no sign of differentiation and appeared as elongated spindle cells in sections. These cells looked columnar and highly polarized after being cultured on ECM gel surfaces. They were similar to epithelial cells from the corresponding tissue fragment. Cultured on ECM gel, the ciliated epithelial cells of human oviducts appeared ultrastructurally similar to glandular cells from the human uterus. Cilia did not form under culture conditions. It seems that human uterine and oviduct epithelial cells can acquire polarized morphology and differentiated states on ECM gel after having lost it on plastic surfaces and that ECM gel by itself is not enough to induce cilia formation in culture.

  11. Mitochondrial structure in steroid-producing cells: three-dimensional reconstruction of human Leydig cell mitochondria by electron microscopic tomography.

    Science.gov (United States)

    Prince, Frederick P; Buttle, Karolyn F

    2004-05-01

    Mitochondria of human Leydig cells were reconstructed in three dimension utilizing the technique of electron microscopic tomography to obtain a better understanding of the topology of the internal membrane system and the relationship of these cristae to the inner boundary membrane (IBM). Cristae structure, in many respects, is consistent with previous tomographic studies from typical mitochondria, i.e., mitochondria from nonsteroid-producing cells. Cristae are diverse in form, with well-defined lamellar cristae interconnected to pleomorphic and tubular regions. Occasional fenestrations are present in the lamellar regions. Also consistent with other mitochondria studied by tomography, the openings of the cristae to the IBM (referred to as crista junctions) are roughly circular or elliptical and approximately 20-25 nm in diameter. Morphological contact sites between the outer mitochondrial membrane and IBM are also present. Cristae membranes in these steroid-producing mitochondria are often found in close proximity to the IBM. Unique to steroid-producing mitochondria is a form of the cristae in which multiple lamellae are in very close apposition, previously defined as the lamellar association. Tomographic reconstructions of the lamellar association reveal that these well-organized membranes also open to the IBM via crista junctions. These regions of closely apposed lamellar cristae are also interconnected and display small tubular extensions from the lamellae. The current study is the first electron microscopic tomography study of mitochondria from steroid-producing cells. The results show the cristae interconnect to form an extensive internal membrane system, which is perhaps better termed the cristae compartment. This internal membrane system is notable due to the high surface area with few small openings to the IBM. Such a morphology is more analogous to the thylakoid membrane system of chloroplasts than the long-standing view of mitochondrial cristae. The

  12. Amyloid-beta leads to impaired cellular respiration, energy production and mitochondrial electron chain complex activities in human neuroblastoma cells.

    Science.gov (United States)

    Rhein, V; Baysang, G; Rao, S; Meier, F; Bonert, A; Müller-Spahn, F; Eckert, A

    2009-09-01

    Evidence suggests that amyloid-beta (Abeta) protein is a key factor in the pathogenesis of Alzheimer's disease (AD) and it has been recently proposed that mitochondria are involved in the biochemical pathway by which Abeta can lead to neuronal dysfunction. Here we investigated the specific effects of Abeta on mitochondrial function under physiological conditions. Mitochondrial respiratory functions and energy metabolism were analyzed in control and in human wild-type amyloid precursor protein (APP) stably transfected human neuroblastoma cells (SH-SY5Y). Mitochondrial respiratory capacity of mitochondrial electron transport chain (ETC) in vital cells was measured with a high-resolution respirometry system (Oxygraph-2k). In addition, we determined the individual activities of mitochondrial complexes I-IV that compose ETC and ATP cellular levels. While the activities of complexes I and II did not change between cell types, complex IV activity was significantly reduced in APP cells. In contrast, activity of complex III was significantly enhanced in APP cells, as compensatory response in order to balance the defect of complex IV. However, this compensatory mechanism could not prevent the strong impairment of total respiration in vital APP cells. As a result, the respiratory control ratio (state3/state4) together with ATP production decreased in the APP cells in comparison with the control cells. Chronic exposure to soluble Abeta protein may result in an impairment of energy homeostasis due to a decreased respiratory capacity of mitochondrial electron transport chain which, in turn, may accelerate neurons demise.

  13. Light- and electron microscopical studies of interstitial cells of Cajal and muscle cells at the submucosal border of human colon

    DEFF Research Database (Denmark)

    Rumessen, J J; Peters, S; Thuneberg, L

    1993-01-01

    It has been suggested that interstitial cells of Cajal (ICC) at the submucosal border of the colonic circular muscle are pacemaker cells. We studied smooth muscle cells and ICC at the submucosal surface of the circular muscle layer of the normal human colon....

  14. Analysis of nuclear fiber cell compaction in transparent and cataractous diabetic human lenses by scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Kuszak Jer R

    2003-01-01

    Full Text Available Abstract Background Compaction of human ocular lens fiber cells as a function of both aging and cataractogenesis has been demonstrated previously using scanning electron microscopy. The purpose of this investigation is to quantify morphological differences in the inner nuclear regions of cataractous and non-cataractous human lenses from individuals with diabetes. The hypothesis is that, even in the presence of the osmotic stress caused by diabetes, compaction rather than swelling occurs in the nucleus of diabetic lenses. Methods Transparent and nuclear cataractous lenses from diabetic patients were examined by scanning electron microscopy (SEM. Measurements of the fetal nuclear (FN elliptical angles (anterior and posterior, embryonic nuclear (EN anterior-posterior (A-P axial thickness, and the number of EN fiber cell membrane folds over 20 μm were compared. Results Diabetic lenses with nuclear cataract exhibited smaller FN elliptical angles, smaller EN axial thicknesses, and larger numbers of EN compaction folds than their non-cataractous diabetic counterparts. Conclusion As in non-diabetic lenses, the inner nuclei of cataractous lenses from diabetics were significantly more compacted than those of non-cataractous diabetics. Little difference between diabetic and non-diabetic compaction levels was found, suggesting that diabetes does not affect the degree of compaction. However, consistent with previous proposals, diabetes does appear to accelerate the formation of cataracts that are similar to age-related nuclear cataracts in non-diabetics. We conclude that as scattering increases in the diabetic lens with cataract formation, fiber cell compaction is significant.

  15. Preservation of protein fluorescence in embedded human dendritic cells for targeted 3D light and electron microscopy.

    Science.gov (United States)

    Höhn, K; Fuchs, J; Fröber, A; Kirmse, R; Glass, B; Anders-Össwein, M; Walther, P; Kräusslich, H-G; Dietrich, C

    2015-08-01

    In this study, we present a correlative microscopy workflow to combine detailed 3D fluorescence light microscopy data with ultrastructural information gained by 3D focused ion beam assisted scanning electron microscopy. The workflow is based on an optimized high pressure freezing/freeze substitution protocol that preserves good ultrastructural detail along with retaining the fluorescence signal in the resin embedded specimens. Consequently, cellular structures of interest can readily be identified and imaged by state of the art 3D confocal fluorescence microscopy and are precisely referenced with respect to an imprinted coordinate system on the surface of the resin block. This allows precise guidance of the focused ion beam assisted scanning electron microscopy and limits the volume to be imaged to the structure of interest. This, in turn, minimizes the total acquisition time necessary to conduct the time consuming ultrastructural scanning electron microscope imaging while eliminating the risk to miss parts of the target structure. We illustrate the value of this workflow for targeting virus compartments, which are formed in HIV-pulsed mature human dendritic cells. © 2015 The Authors Journal of Microscopy © 2015 Royal Microscopical Society.

  16. Electron Transfer Pathways in Cell

    OpenAIRE

    Yan Liu

    2012-01-01

    Analysis of the electron salvation process data indicates that the electron transfer between the electron donor and acceptor is hindered by the electron salvation process. It is proposed that the electron transfer in the cell environment must be assisted by intermediate messenger called the “transport protein”.

  17. Electronic Textbook in Human Physiology.

    Science.gov (United States)

    Broering, Naomi C.; Lilienfield, Lawrence S.

    1994-01-01

    Describes the development of an electronic textbook in human physiology at the Georgetown University Medical Center Library that was designed to enhance learning and visualization through a prototype knowledge base of core instructional materials stored in digital format on Macintosh computers. The use of computers in the medical curriculum is…

  18. Dose conversion coefficients for monoenergetic electrons incident on a realistic human eye model with different lens cell populations

    Energy Technology Data Exchange (ETDEWEB)

    Nogueira, P; Vaz, P [Technological and Nuclear Institute, Estrada Nacional No 10, 2686-953 Sacavem (Portugal); Zankl, M; Schlattl, H, E-mail: pedro.nogueira@helmholtz-muenchen.de [Helmholtz Zentrum Muenchen-German Research Center for Environmental Health, Research Unit Medical Radiation Physics and Diagnostics, Ingolstaedter Landstrasse 1, D-85764 Neuherberg (Germany)

    2011-11-07

    The radiation-induced posterior subcapsular cataract has long been generally accepted to be a deterministic effect that does not occur at doses below a threshold of at least 2 Gy. Recent epidemiological studies indicate that the threshold for cataract induction may be much lower or that there may be no threshold at all. A thorough study of this subject requires more accurate dose estimates for the eye lens than those available in ICRP Publication 74. Eye lens absorbed dose per unit fluence conversion coefficients for electron irradiation were calculated using a geometrical model of the eye that takes into account different cell populations of the lens epithelium, together with the MCNPX Monte Carlo radiation transport code package. For the cell population most sensitive to ionizing radiation-the germinative cells-absorbed dose per unit fluence conversion coefficients were determined that are up to a factor of 4.8 higher than the mean eye lens absorbed dose conversion coefficients for electron energies below 2 MeV. Comparison of the results with previously published values for a slightly different eye model showed generally good agreement for all electron energies. Finally, the influence of individual anatomical variability was quantified by positioning the lens at various depths below the cornea. A depth difference of 2 mm between the shallowest and the deepest location of the germinative zone can lead to a difference between the resulting absorbed doses of up to nearly a factor of 5000 for electron energy of 0.7 MeV.

  19. Vapours of US and EU Market Leader Electronic Cigarette Brands and Liquids Are Cytotoxic for Human Vascular Endothelial Cells.

    Directory of Open Access Journals (Sweden)

    Raphaela Putzhammer

    Full Text Available The present study was conducted to provide toxicological data on e-cigarette vapours of different e-cigarette brands and liquids from systems viewed as leaders in the e-cigarette market and to compare e-cigarette vapour toxicity to the toxicity of conventional strong high-nicotine cigarette smoke. Using an adapted version of a previously constructed cigarette smoke constituent sampling device, we collected the hydrophilic fraction of e-cigarette vapour and exposed human umbilical vein endothelial cells (HUVECs to the mixture of compounds present in the vapour of 4 different single-use e-cigarettes, 6 different liquid vapours produced by the same refillable e-cigarette, and one e-cigarette with an exchangeable liquid cartridge. After incubation of cells with various concentrations and for various periods of time we analysed cell death induction, proliferation rates, the occurrence of intra-cellular reactive oxygen species, cell morphology, and we also measured e-cigarette heating coil temperatures. Overall, conventional cigarette smoke extract showed the most severe impact on endothelial cells. However, some e-cigarette vapour extracts showed high cytotoxicity, inhibition of cell proliferation, and alterations in cell morphology, which were comparable to conventional high-nicotine cigarettes. The vapours generated from different liquids using the same e-cigarette show substantial differences, pointing to the liquids as an important source for toxicity. E-cigarette vapour-mediated induction of oxidative stress was significant in one out of the 11 analysed vapours. There is a high variability in the acute cytotoxicity of e-cigarette vapours depending on the liquid and on the e-cigarettes used. Some products showed toxic effects close to a conventional high-nicotine cigarette. Liquid nicotine, menthol content, and the formation of acute intracellular reactive oxygen species do not seem to be the central elements in e-cigarette vapour toxicity.

  20. Electronic cigarettes: human health effects.

    Science.gov (United States)

    Callahan-Lyon, Priscilla

    2014-05-01

    With the rapid increase in use of electronic nicotine delivery systems (ENDS), such as electronic cigarettes (e-cigarettes), users and non-users are exposed to the aerosol and product constituents. This is a review of published data on the human health effects of exposure to e-cigarettes and their components. Literature searches were conducted through September 2013 using multiple electronic databases. Forty-four articles are included in this analysis. E-cigarette aerosols may contain propylene glycol, glycerol, flavourings, other chemicals and, usually, nicotine. Aerosolised propylene glycol and glycerol produce mouth and throat irritation and dry cough. No data on the effects of flavouring inhalation were identified. Data on short-term health effects are limited and there are no adequate data on long-term effects. Aerosol exposure may be associated with respiratory function impairment, and serum cotinine levels are similar to those in traditional cigarette smokers. The high nicotine concentrations of some products increase exposure risks for non-users, particularly children. The dangers of secondhand and thirdhand aerosol exposure have not been thoroughly evaluated. Scientific evidence regarding the human health effects of e-cigarettes is limited. While e-cigarette aerosol may contain fewer toxicants than cigarette smoke, studies evaluating whether e-cigarettes are less harmful than cigarettes are inconclusive. Some evidence suggests that e-cigarette use may facilitate smoking cessation, but definitive data are lacking. No e-cigarette has been approved by FDA as a cessation aid. Environmental concerns and issues regarding non-user exposure exist. The health impact of e-cigarettes, for users and the public, cannot be determined with currently available data.

  1. Electronic Interfacing with Living Cells

    Science.gov (United States)

    Fleming, James T.

    The direct interfacing of living cells with inorganic electronic materials, components or systems has led to the development of two broad categories of devices that can (1) transduce biochemical signals generated by biological components into electrical signals and (2) transduce electronically generated signals into biochemical signals. The first category of devices permits the monitoring of living cells, the second, enables control of cellular processes. This review will survey this exciting area with emphasis on the fundamental issues and obstacles faced by researchers. Devices and applications that use both prokaryotic (microbial) and eukaryotic (mammalian) cells will be covered. Individual devices described include microbial biofuel cells that produce electricity, bioelectrical reactors that enable electronic control of cellular metabolism, living cell biosensors for the detection of chemicals and devices that permit monitoring and control of mammalian physiology.

  2. Liquid Cell Transmission Electron Microscopy

    Science.gov (United States)

    Liao, Hong-Gang; Zheng, Haimei

    2016-05-01

    Liquid cell transmission electron microscopy (TEM) has attracted significant interest in recent years. With nanofabricated liquid cells, it has been possible to image through liquids using TEM with subnanometer resolution, and many previously unseen materials dynamics have been revealed. Liquid cell TEM has been applied to many areas of research, ranging from chemistry to physics, materials science, and biology. So far, topics of study include nanoparticle growth and assembly, electrochemical deposition and lithiation for batteries, tracking and manipulation of nanoparticles, catalysis, and imaging of biological materials. In this article, we first review the development of liquid cell TEM and then highlight progress in various areas of research. In the study of nanoparticle growth, the electron beam can serve both as the illumination source for imaging and as the input energy for reactions. However, many other research topics require the control of electron beam effects to minimize electron beam damage. We discuss efforts to understand electron beam-liquid matter interactions. Finally, we provide a perspective on future challenges and opportunities in liquid cell TEM.

  3. Scanning electron microscopy of human and murine melanoma cells exposed to medium chain-length (C6-C12) dicarboxylic acids in tissue culture.

    Science.gov (United States)

    Breathnach, A S; Robins, E J; Bhasin, Y; Ethridge, L; Nazzaro-Porro, M; Passi, S; Picardo, M

    1987-07-01

    Human and murine (Harding-Passey and Cloudman) melanoma cells were exposed to various concentrations (1 x 10(-3) M-1 x 10(-1) M) of adipic (C6), azelaic (C9), and dodecanedioic (C12) acids for 1-6 hours in tissue culture, and the effects on shape and surface topography were examined by scanning electron microscopy. Effects, i.e., rounding up, concentration of microvilli, blebbing, and prominence of retraction fibrils were time and dose dependent, and for the same concentrations and exposure times, C12 had a greater effect than C9, and both a significantly greater effect than C6. These differential reactions to the three diacids parallel previously reported effects on cell kinetics and viability. The changes could be due to a prime effect on the cell membrane, or they might reflect phases of the cell cycle directed by action of the diacids on the nucleus; this latter seems unlikely. An effect on the cytoskeleton is possibly involved.

  4. Effect of surgical wound fluids after intraoperative electron radiotherapy on the cancer stem cell phenotype in a panel of human breast cancer cell lines

    Science.gov (United States)

    Zaleska, Karolina; Suchorska, Wiktoria Maria; Przybyła, Anna; Murawa, Dawid

    2016-01-01

    The wound healing process after surgery alters the area surrounding the original tumor and around the scar, and the modified microenvironment is more favorable for tumor recurrence. Intraoperative radiotherapy (IORT) is one of the more novel strategies in breast cancer (BC) treatment. Irradiation during surgery has effects on the tumor microenvironment, abrogating the proliferative cascade induced by surgical wound healing. The aim of the present study was to determine the effect of surgical wound fluids from IOERT treatment (RT-WF) compared with wound fluids from conservative-breast surgery only (WF) on the cancer stem cell phenotype in a panel of BC cell lines. Post-operative wound fluids were derived from patients with BC who underwent a tumor resection (quadrantectomy) plus intraoperative electron radiotherapy using a single dose of ≤10 Gy on the tumor bed and surrounding tissues, or from those who underwent a tumor resection without IOERT. Cell lines were incubated with 10% wound fluids, and after 4 days, the cluster of differentiation (CD)44+/CD24−/low phenotype and aldehyde dehydrogenase 1 (ALDH1) activity were determined by flow cytometry. The two types of fluid each affected the CD44+/CD24−/low phenotype. The results varied markedly between each cell line, even for the same histological subtypes. RT-WF decreased the CD44+/CD24−/low populations in the basal-like BT-549 and MDA-MB-468 cell lines, whereas in the luminal type MCF7 cell line, the two fluids inhibited these populations. The HER-OE subtypes harbored a minimal CD44+/CD24−/low population, but the growth of SK-BR-3 was stimulated by the two post-operative fluids. WF exhibited a stronger effect on ALDH1 activity compared with RT-WF. The stimulatory effect was dependent on the histological subtype of the cell line and the strongest dependence was observed in luminal subtypes characterized by low dehydrogenase activity in the control group. The present results enable a better understanding of

  5. Auger electron-emitting (111)In-DTPA-NLS-CSL360 radioimmunoconjugates are cytotoxic to human acute myeloid leukemia (AML) cells displaying the CD123(+)/CD131(-) phenotype of leukemia stem cells.

    Science.gov (United States)

    Gao, Catherine; Leyton, Jeffrey V; Schimmer, Aaron D; Minden, Mark; Reilly, Raymond M

    2016-04-01

    Chimeric IgG1 monoclonal antibody CSL360 recognizes the CD123(+)/CD131(-) phenotype expressed by leukemic stem cells (LSC). Auger electron-emitting (111)In-DTPA-NLS-CSL360 radioimmunoconjugates incorporating nuclear translocation sequence (NLS) peptides bound specifically to Raji cells transfected with CD123 and exhibited a KD of 11nmols/L in a competition receptor-binding assay using CD123-transfected CHO cells. (111)In-DTPA-NLS-CSL360 was bound, internalized and transported to the nucleus of human AML-5 myeloid leukemia cells. The clonogenic survival of AML-5 cells was reduced by (111)In-DTPA-NLS-CSL360 up to 3.7-fold. Isotype control (111)In-DTPA-chIgG1 was 2-fold less cytotoxic, and unlabeled CSL360, DTPA-NLS-CSL360 or free (111)In acetate did not decrease cell survival. These results are promising for further evaluation of (111)In-DTPA-NLS-CSL360 for Auger electron radioimmunotherapy of AML targeting the critical LSC subpopulation. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. ELECTRON BOMBARDMENT OF SILICON SOLAR CELLS,

    Science.gov (United States)

    DAMAGE, ELECTRON IRRADIATION, SOLAR CELLS , SILICON, PHOTOELECTRIC CELLS(SEMICONDUCTOR), QUARTZ, GLASS, SHIELDING, CRYSTAL DEFECTS, HEAT TREATMENT, ARTIFICIAL SATELLITES, SPACECRAFT, GRAPHICS, GRAPHICS.

  7. Human mesenchymal stem cells

    DEFF Research Database (Denmark)

    Abdallah, Basem; Kassem, Moustapha

    2008-01-01

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

  8. Cytotoxicity and mitogenicity assays with real-time and label-free monitoring of human granulosa cells with an impedance-based signal processing technology intergrating micro-electronics and cell biology.

    Science.gov (United States)

    Oktem, Ozgur; Bildik, Gamze; Senbabaoglu, Filiz; Lack, Nathan A; Akin, Nazli; Yakar, Feridun; Urman, Defne; Guzel, Yilmaz; Balaban, Basak; Iwase, Akira; Urman, Bulent

    2016-04-01

    A recently developed technology (xCelligence) integrating micro-electronics and cell biology allows real-time, uninterrupted and quantitative analysis of cell proliferation, viability and cytotoxicity by measuring the electrical impedance of the cell population in the wells without using any labeling agent. In this study we investigated if this system is a suitable model to analyze the effects of mitogenic (FSH) and cytotoxic (chemotherapy) agents with different toxicity profiles on human granulosa cells in comparison to conventional methods of assessing cell viability, DNA damage, apoptosis and steroidogenesis. The system generated the real-time growth curves of the cells, and determined their doubling times, mean cell indices and generated dose-response curves after exposure to cytotoxic and mitogenic stimuli. It accurately predicted the gonadotoxicity of the drugs and distinguished less toxic agents (5-FU and paclitaxel) from more toxic ones (cisplatin and cyclophosphamide). This platform can be a useful tool for specific end-point assays in reproductive toxicology. Copyright © 2015 Elsevier Inc. All rights reserved.

  9. Scanning electron microscopy of interaction of peripheral blood lymphocytes from colonic cancer patients with human colonic cancer-derived cells; P-4788.

    Directory of Open Access Journals (Sweden)

    Sugihara,Mutsuto

    1979-12-01

    Full Text Available Peripheral blood lymphocytes and the various lymphocyte fractions from patients with cancer of the colon were cultivated with target cells (P-4788 derived from the colon cancer. Changes in the surface ultrastructure during tumor cell destruction were studied by scanning electron microscopy (SEM. P-4788 cells adhering to the coverslip showed various surface activity. The surfaces of some cells were relatively flat; others were smooth or had fine granules. Still other cells were villous, round or had marked blebs. When host lymphocytes were added to the target cells, adhesion of the two cell groups began by many fine projections. After incubation for 6 h, some lymphocytes had adhered to the target cells. Many lymphocytes had adhered to the target tumor cells by 24--48 h incubation. Ultimately the tumor cells became swollen and disrupted. Most lymphocytes adherent to the target cells had few microvilli. Lymphocytes after elimination of phagocytes by carbonyl iron treatment also adhered readily. Some target cells showed adhesion with lymphocytes passed through nylon-wool columns, although the number of lymphocytes adhering was fewer than in the case of lymphocytes not passed through nylon-wool columns. T cells were collected from lymphocytes that form rosettes with SRBC by isolation with NH4Cl. They had markedly elongated microvilli which in places were sparsely scattered and tended to be localized on the side, a finding which suggests loss of cell activity by the time of SEM. Only a few T cells adhered to target cells and they seemed to be T cells without activity. It was thought that there are cytotoxic cells among T cells and that the co-existence of T cells, non-T cells and monocytes caused target cell destruction.

  10. The crocidolite fibres interaction with human mesothelial cells as investigated by combining electron microscopy, atomic force and scanning near-field optical microscopy.

    Science.gov (United States)

    Andolfi, Laura; Trevisan, Elisa; Zweyer, Marina; Prato, Stefano; Troian, Barbara; Vita, Francesca; Borelli, Violetta; Soranzo, Maria Rosa; Melato, Mauro; Zabucchi, Giuliano

    2013-03-01

    In this study, we have performed a morphological analysis of crocidolite fibres interaction with mesothelial cells (MET5A) by combining conventional electron microscopy with atomic force (AFM) and scanning near-field optical microscopy (SNOM). After 6-h exposure at a crocidolite dose of 5 μg cm(-2), 90% of MET5A cells interact with fibres that under these conditions have a low cytotoxic effect. SEM images point out that fibres can be either engulfed by the cells that lose their typical morphology or they can accumulate over or partially inside the cells, which preserve their typical spread morphology. By using AFM we are able to directly visualize the entry-site of nanometric-sized fibres at the plasma membrane of the spread mesothelial cells. More importantly, the crocidolite fibres that are observed to penetrate the plasma membrane in SNOM topography can be simultaneously followed beneath the cell surface in the SNOM optical images. The analysis of SNOM data demonstrates the entrance of crocidolite fibres in proximity of nuclear compartment, as observed also in the TEM images. Our findings indicate that the combination of conventional electron microscopy with novel nanoscopic techniques can be considered a promising approach to achieve a comprehensive morphological description of the interaction between asbestos fibres and mesothelial cells that represents the early event in fibre pathogenesis.

  11. Cell encoding recombinant human erythropoietin

    Energy Technology Data Exchange (ETDEWEB)

    Beck, A.K.; Withy, R.M.; Zabrecky, J.R.; Masiello, N.C.

    1990-09-04

    This patent describes a C127 cell transformed with a recombinant DNA vector. It comprises: a DNA sequence encoding human erythropoietin, the transformed cell being capable of producing N-linked and O-linked glycosylated human erythropoietin.

  12. Printed Electronic Devices in Human Spaceflight

    Science.gov (United States)

    Bacon, John B.

    2004-01-01

    The space environment requires robust sensing, control, and automation, whether in support of human spaceflight or of robotic exploration. Spaceflight embodies the known extremes of temperature, radiation, shock, vibration, and static loads, and demands high reliability at the lowest possible mass. Because printed electronic circuits fulfill all these requirements, printed circuit technology and the exploration of space have been closely coupled throughout their short histories. In this presentation, we will explore the space (and space launch) environments as drivers of printed circuit design, a brief history of NASA's use of printed electronic circuits, and we will examine future requirements for such circuits in our continued exploration of space.

  13. Fast Electronic Solar Cell Tester

    Science.gov (United States)

    Lathrop, J. W.; Saylor, C. R.

    1983-01-01

    Microcomputer controlled system gather current and voltage data. System consists of light source, microcomputer, programable dc power supply, analog/ digital interface, and data storage display equipment. Applies series of test loads to cell via programable dc power supply to obtain I/V characteristic curve and key cell-peformance parameter. Apparatus and programming technique are applicable to devices such as batteries and sensors.

  14. Electron Microscopy of Nanostructures in Cells

    DEFF Research Database (Denmark)

    Købler, Carsten

    with cells is therefore increasingly more relevant from both an engineering and a toxicological viewpoint. My work involves developing and exploring electron microscopy (EM) for imaging nanostructures in cells, for the purpose of understanding nanostructure-cell interactions in terms of their possibilities...... in science and concerns in toxicology. In the present work, EM methods for imaging nanostructure-cell interactions have been explored, and the complex interactions documented and ordered. In particular the usability of the focused ion beam scanning electron microscope (FIB-SEM) was explored. Using EM...

  15. Electron Tomography in Plant Cell Biology

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This review focuses on the contribution of electron tomography-based techniques to our understanding of cellular processes in plant cells. Electron microscopy techniques have evolved to provide better three-dimensional resolution and improved preservation of the subcellular components. In particular, the combination of cryofixation/freeze substitution and electron tomography have allowed plant cell biologists to image organelles and macromolecular complexes in their native cellular context with unprecedented three-dimensional resolution (4-7 nm). Until now, electron tomography has been applied in plant cell biology for the study of cytokinesis, Golgi structure and trafficking, formation of plant endosome/prevacuolar compartments, and organization of photosynthetic membranes. We discuss in this review the new insights that these tomographic studies have brought to the plant biology field.

  16. Genome engineering in human cells.

    Science.gov (United States)

    Song, Minjung; Kim, Young-Hoon; Kim, Jin-Soo; Kim, Hyongbum

    2014-01-01

    Genome editing in human cells is of great value in research, medicine, and biotechnology. Programmable nucleases including zinc-finger nucleases, transcription activator-like effector nucleases, and RNA-guided engineered nucleases recognize a specific target sequence and make a double-strand break at that site, which can result in gene disruption, gene insertion, gene correction, or chromosomal rearrangements. The target sequence complexities of these programmable nucleases are higher than 3.2 mega base pairs, the size of the haploid human genome. Here, we briefly introduce the structure of the human genome and the characteristics of each programmable nuclease, and review their applications in human cells including pluripotent stem cells. In addition, we discuss various delivery methods for nucleases, programmable nickases, and enrichment of gene-edited human cells, all of which facilitate efficient and precise genome editing in human cells.

  17. Electron microscopy of human fascia lata: focus on telocytes.

    Science.gov (United States)

    Dawidowicz, Joanna; Szotek, Sylwia; Matysiak, Natalia; Mielańczyk, Łukasz; Maksymowicz, Krzysztof

    2015-10-01

    From the histological point of view, fascia lata is a dense connective tissue. Although extracellular matrix is certainly the most predominant fascia's feature, there are also several cell populations encountered within this structure. The aim of this study was to describe the existence and characteristics of fascia lata cell populations viewed through a transmission electron microscope. Special emphasis was placed on telocytes as a particular interstitial cell type, recently discovered in a wide variety of tissues and organs such as the heart, skeletal muscles, skin, gastrointestinal tract, uterus and urinary system. The conducted study confirmed the existence of a telocyte population in fascia lata samples. Those cells fulfil main morphological criteria of telocytes, namely, the presence of very long, thin cell processes (telopodes) extending from a relatively small cell body. Aside from telocytes, we have found fibroblasts, mast cells and cells with features of myofibroblastic differentiation. This is the first time it has been shown that telocytes exist in human fascia. Currently, the exact role of those cells within the fascia is unknown and definitely deserves further attention. One can speculate that fascia lata telocytes likewise telocytes in other organs may be involved in regeneration, homeostasis and intracellular signalling.

  18. Electron microscopy of human fascia lata: focus on telocytes

    Science.gov (United States)

    Dawidowicz, Joanna; Szotek, Sylwia; Matysiak, Natalia; Mielańczyk, Łukasz; Maksymowicz, Krzysztof

    2015-01-01

    From the histological point of view, fascia lata is a dense connective tissue. Although extracellular matrix is certainly the most predominant fascia’s feature, there are also several cell populations encountered within this structure. The aim of this study was to describe the existence and characteristics of fascia lata cell populations viewed through a transmission electron microscope. Special emphasis was placed on telocytes as a particular interstitial cell type, recently discovered in a wide variety of tissues and organs such as the heart, skeletal muscles, skin, gastrointestinal tract, uterus and urinary system. The conducted study confirmed the existence of a telocyte population in fascia lata samples. Those cells fulfil main morphological criteria of telocytes, namely, the presence of very long, thin cell processes (telopodes) extending from a relatively small cell body. Aside from telocytes, we have found fibroblasts, mast cells and cells with features of myofibroblastic differentiation. This is the first time it has been shown that telocytes exist in human fascia. Currently, the exact role of those cells within the fascia is unknown and definitely deserves further attention. One can speculate that fascia lata telocytes likewise telocytes in other organs may be involved in regeneration, homeostasis and intracellular signalling. PMID:26311620

  19. Environmental scanning electron microscopy in cell biology.

    Science.gov (United States)

    McGregor, J E; Staniewicz, L T L; Guthrie Neé Kirk, S E; Donald, A M

    2013-01-01

    Environmental scanning electron microscopy (ESEM) (1) is an imaging technique which allows hydrated, insulating samples to be imaged under an electron beam. The resolution afforded by this technique is higher than conventional optical microscopy but lower than conventional scanning electron microscopy (CSEM). The major advantage of the technique is the minimal sample preparation needed, making ESEM quick to use and the images less susceptible to the artifacts that the extensive sample preparation usually required for CSEM may introduce. Careful manipulation of both the humidity in the microscope chamber and the beam energy are nevertheless essential to prevent dehydration and beam damage artifacts. In some circumstances it is possible to image live cells in the ESEM (2).In the following sections we introduce the fundamental principles of ESEM imaging before presenting imaging protocols for plant epidermis, mammalian cells, and bacteria. In the first two cases samples are imaged using the secondary electron (topographic) signal, whereas a transmission technique is employed to image bacteria.

  20. Some New Aspects of Langerhans Cells in the Human Epidermis: Light and Electron Microscopic Observations on the Swelling Sites Seen in the Process Terminals of the Dendritic Cells Described by Langerhans in 1868

    OpenAIRE

    Oota, Shigeo

    1999-01-01

    In 1868, Langerhans discovered the dendritic cells now generally called Langerhans cells (LCs) in the human epidermis using the gold impregnation method. He pointed out that the terminals of the upward running processes of the cells end with button-like swellings under the cornified layer. In 1951, Ferreira-Marques classified the shapes of the terminals into 7 types, named the largest one Organum trompiforme and reckoned it to be a sense receptor. However, the swellings of the process termina...

  1. Grape seed extract targets mitochondrial electron transport chain complex III and induces oxidative and metabolic stress leading to cytoprotective autophagy and apoptotic death in human head and neck cancer cells.

    Science.gov (United States)

    Shrotriya, Sangeeta; Deep, Gagan; Lopert, Pamela; Patel, Manisha; Agarwal, Rajesh; Agarwal, Chapla

    2015-12-01

    Head and neck squamous cell carcinoma (HNSCC) is a major killer worldwide and innovative measures are urgently warranted to lower the morbidity and mortality caused by this malignancy. Aberrant redox and metabolic status in HNSCC cells offer a unique opportunity to specifically target cancer cells. Therefore, we investigated the efficacy of grape seed extract (GSE) to target the redox and bioenergetic alterations in HNSCC cells. GSE treatment decreased the mitochondrial electron transport chain complex III activity, increased the mitochondrial superoxide levels and depleted the levels of cellular antioxidant (glutathione), thus resulting in the loss of mitochondrial membrane potential in human HNSCC Detroit 562 and FaDu cells. Polyethylene glycol-SOD addition reversed the GSE-mediated apoptosis without restoring complex III activity. Along with redox changes, GSE inhibited the extracellular acidification rate (representing glycolysis) and oxygen consumption rate (indicating oxidative phosphorylation) leading to metabolic stress in HNSCC cells. Molecular studies revealed that GSE activated AMP-activated protein kinase (AMPK), and suppressed Akt/mTOR/4E-BP1/S6K signaling in both Detroit 562 and FaDu cells. Interestingly, GSE increased the autophagic load specifically in FaDu cells, and autophagy inhibition significantly augmented the apoptosis in these cells. Consistent with in vitro results, in vivo analyses also showed that GSE feeding in nude mice activated AMPK and induced-autophagy in FaDu xenograft tumor tissues. Overall, these findings are innovative as we for the first time showed that GSE targets ETC complex III and induces oxidative and metabolic stress, thereby, causing autophagy and apoptotic death in HNSCC cells. © 2014 Wiley Periodicals, Inc.

  2. CLOSTRIDIUM SPORE ATTACHMENT TO HUMAN CELLS

    Energy Technology Data Exchange (ETDEWEB)

    PANESSA-WARREN,B.; TORTORA,G.; WARREN,J.

    1997-08-10

    This paper uses high resolution scanning electron microscopy (SEM) with a LaB6 gun and the newest commercial field emission guns, to obtain high magnification images of intact clostridial spores throughout the activation/germination/outgrowth process. By high resolution SEM, the clostridial exosporial membrane can be seen to produce numerous delicate projections (following activation), that extend from the exosporial surface to a nutritive substrate (agar), or cell surface when anaerobically incubated in the presence of human cells (embryonic fibroblasts and colon carcinoma cells). Magnifications of 20,000 to 200,000Xs at accelerating voltages low enough to minimize or eliminate specimen damage (1--5 kV) have permitted the entire surface of C.sporogenes and C.difficile endospores to be examined during all stages of germination. The relationships between the spore and the agar or human cell surface were also clearly visible.

  3. Diffusion inside living human cells

    DEFF Research Database (Denmark)

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

    2012-01-01

    Naturally occurring lipid granules diffuse in the cytoplasm and can be used as tracers to map out the viscoelastic landscape inside living cells. Using optical trapping and single particle tracking we found that lipid granules exhibit anomalous diffusion inside human umbilical vein endothelial...... 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...

  4. 3D correlative light and electron microscopy of cultured cells using serial blockface scanning electron microscopy

    Science.gov (United States)

    Lerner, Thomas R.; Burden, Jemima J.; Nkwe, David O.; Pelchen-Matthews, Annegret; Domart, Marie-Charlotte; Durgan, Joanne; Weston, Anne; Jones, Martin L.; Peddie, Christopher J.; Carzaniga, Raffaella; Florey, Oliver; Marsh, Mark; Gutierrez, Maximiliano G.

    2017-01-01

    ABSTRACT The processes of life take place in multiple dimensions, but imaging these processes in even three dimensions is challenging. Here, we describe a workflow for 3D correlative light and electron microscopy (CLEM) of cell monolayers using fluorescence microscopy to identify and follow biological events, combined with serial blockface scanning electron microscopy to analyse the underlying ultrastructure. The workflow encompasses all steps from cell culture to sample processing, imaging strategy, and 3D image processing and analysis. We demonstrate successful application of the workflow to three studies, each aiming to better understand complex and dynamic biological processes, including bacterial and viral infections of cultured cells and formation of entotic cell-in-cell structures commonly observed in tumours. Our workflow revealed new insight into the replicative niche of Mycobacterium tuberculosis in primary human lymphatic endothelial cells, HIV-1 in human monocyte-derived macrophages, and the composition of the entotic vacuole. The broad application of this 3D CLEM technique will make it a useful addition to the correlative imaging toolbox for biomedical research. PMID:27445312

  5. 3D correlative light and electron microscopy of cultured cells using serial blockface scanning electron microscopy.

    Science.gov (United States)

    Russell, Matthew R G; Lerner, Thomas R; Burden, Jemima J; Nkwe, David O; Pelchen-Matthews, Annegret; Domart, Marie-Charlotte; Durgan, Joanne; Weston, Anne; Jones, Martin L; Peddie, Christopher J; Carzaniga, Raffaella; Florey, Oliver; Marsh, Mark; Gutierrez, Maximiliano G; Collinson, Lucy M

    2017-01-01

    The processes of life take place in multiple dimensions, but imaging these processes in even three dimensions is challenging. Here, we describe a workflow for 3D correlative light and electron microscopy (CLEM) of cell monolayers using fluorescence microscopy to identify and follow biological events, combined with serial blockface scanning electron microscopy to analyse the underlying ultrastructure. The workflow encompasses all steps from cell culture to sample processing, imaging strategy, and 3D image processing and analysis. We demonstrate successful application of the workflow to three studies, each aiming to better understand complex and dynamic biological processes, including bacterial and viral infections of cultured cells and formation of entotic cell-in-cell structures commonly observed in tumours. Our workflow revealed new insight into the replicative niche of Mycobacterium tuberculosis in primary human lymphatic endothelial cells, HIV-1 in human monocyte-derived macrophages, and the composition of the entotic vacuole. The broad application of this 3D CLEM technique will make it a useful addition to the correlative imaging toolbox for biomedical research. © 2017. Published by The Company of Biologists Ltd.

  6. Human stromal (mesenchymal) stem cells

    DEFF Research Database (Denmark)

    Aldahmash, Abdullah; Zaher, Walid; Al-Nbaheen, May

    2012-01-01

    Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self-renewal and......Human stromal (mesenchymal) stem cells (hMSC) represent a group of non-hematopoietic stem cells present in the bone marrow stroma and the stroma of other organs including subcutaneous adipose tissue, placenta, and muscles. They exhibit the characteristics of somatic stem cells of self...... of clinical applications, e.g., non-healing bone fractures and defects and also non-skeletal degenerative diseases like heart failure. Currently, the numbers of clinical trials that employ MSC are increasing. However, several biological and biotechnological challenges need to be overcome to benefit from...

  7. Human embryonic stem cells handbook

    Directory of Open Access Journals (Sweden)

    Carlo Alberto Redi

    2013-03-01

    Full Text Available After the Nobel prize in physiology or medicine was awarded jointly to Sir John Gurdon and Shinya Yamanaka for the discovery that mature cells can be reprogrammed to become pluripotent it became imperative to write down the review for a book entirely devoted to human embryonic stem cells (hES, those cells that are a urgent need for researchers, those cells that rekindle the ethical debates and finally, last but not least, those cells whose study paved the way to obtain induced pluripotent stem cells by the OSKC’s Yamanaka method (the OSKC acronim refers, for those not familiar with the topic, to the four stemness genes used to transfect somatic fibroblasts: Oct4, Sox2, Klf4 and c-Myc....

  8. An experimental electronic model for a neuronal cell

    Science.gov (United States)

    Campos-Cantón, I.; Rangel-López, A.; Martel-Gallegos, G.; Zarazúa, S.; Vertiz-Hérnandez, A.

    2014-04-01

    Over the last two decades, the study of information transmission in living beings has acquired great relevance, because it regulates and conducts the functioning of all of the organs in the body. In information transmission pathways, the neuron plays an important role in that it receives, transmits, and processes electrical signals from different parts of the human body; these signals are transmitted as electrical impulses called action potentials, and they transmit information from one neuron to another. In this work, and with the aim of developing experiments for teaching biological processes, we implemented an electronic circuit of the neuron cell device and its mathematical model based on piecewise linear functions.

  9. Human fetal mesenchymal stem cells.

    Science.gov (United States)

    O'Donoghue, Keelin; Chan, Jerry

    2006-09-01

    Stem cells have been isolated at all stages of development from the early developing embryo to the post-reproductive adult organism. However, the fetal environment is unique as it is the only time in ontogeny that there is migration of stem cells in large numbers into different organ compartments. While fetal neural and haemopoietic stem cells (HSC) have been well characterised, only recently have mesenchymal stem cells from the human fetus been isolated and evaluated. Our group have characterised in human fetal blood, liver and bone marrow a population of non-haemopoietic, non-endothelial cells with an immunophenotype similar to adult bone marrow-derived mesenchymal stem cells (MSC). These cells, human fetal mesenchymal stem cells (hfMSC), are true multipotent stem cells with greater self-renewal and differentiation capacity than their adult counterparts. They circulate in first trimester fetal blood and have been found to traffic into the maternal circulation, engrafting in bone marrow, where they remain microchimeric for decades after pregnancy. Though fetal microchimerism has been implicated in the pathogenesis of autoimmune disease, the biological role of hfMSC microchimerism is unknown. Potential downstream applications of hfMSC include their use as a target cell for non-invasive pre-natal diagnosis from maternal blood, and for fetal cellular and gene therapy. Using hfMSC in fetal therapy offers the theoretical advantages of avoidance of immune rejection, increased engraftment, and treatment before disease pathology sets in. Aside from allogeneic hfMSC in utero transplantation, the use of autologous hfMSC has been brought a step forward with the development of early blood sampling techniques, efficient viral transduction and clonal expansion. Work is ongoing to determine hfMSC fate post-transplantation in murine models of genetic disease. In this review we will examine what is known about hfMSC biology, as well as discussing areas for future research. The

  10. Arecoline is cytotoxic for human endothelial cells.

    Science.gov (United States)

    Ullah, Mafaz; Cox, Stephen; Kelly, Elizabeth; Boadle, Ross; Zoellner, Hans

    2014-11-01

    Oral submucous fibrosis is a pre-malignant fibrotic condition caused by areca nut use and involves reduced mucosal vascularity. Arecoline is the principal areca nut alkaloid and is cytotoxic for epithelium and fibroblasts. Endothelial cell cycle arrest is reported on exposure to arecoline, as is cytotoxicity for endothelial-lung carcinoma hybrid cells. We here describe cytotoxicity for primary human endothelial cultures from seven separate donors. Human umbilical vein endothelial cells were exposed to increasing concentrations of arecoline and examined by: phase-contrast microscopy, haemocytometer counts, transmission electron microscopy, lactate dehydrogenase release and the methyl-thiazol-tetrazolium assay. Vacuolation and detachment of endothelium were observed at and above arecoline concentrations of 333 μg/ml or more. Ultrastructural features of cellular stress were seen after 24-h treatment with 111 μg/ml arecoline and included reduced ribosomal studding of endoplasmic reticulum, increased autophagolysosomal structures, increased vacuolation and reduced mitochondrial cristae with slight swelling. Similar changes were seen at 4 h with arecoline at 333 μg/ml or above, but with more severe mitochondrial changes including increased electron density of mitochondrial matrix and greater cristal swelling, while by 24 h, these cells were frankly necrotic. Haemocytometer counts were paralleled by both lactate dehydrogenase release and the methyl-thiazol-tetrazolium assays. Arecoline is cytotoxic via necrosis for endothelium, while biochemical assays indicate no appreciable cellular leakage before death and detachment, as well as no clear effect on mitochondrial function in viable cells. Arecoline toxicity may thus contribute to reduced vascularity in oral submucous fibrosis. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Practical guide to electronic resources in the humanities

    CERN Document Server

    Dubnjakovic, Ana

    2010-01-01

    From full-text article databases to digitized collections of primary source materials, newly emerging electronic resources have radically impacted how research in the humanities is conducted and discovered. This book, covering high-quality, up-to-date electronic resources for the humanities, is an easy-to-use annotated guide for the librarian, student, and scholar alike. It covers online databases, indexes, archives, and many other critical tools in key humanities disciplines including philosophy, religion, languages and literature, and performing and visual arts. Succinct overviews of key eme

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

    Science.gov (United States)

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

    2014-02-25

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

  13. Developing Humanities Collections in the Digital Age: Exploring Humanities Faculty Engagement with Electronic and Print Resources

    Science.gov (United States)

    Kachaluba, Sarah Buck; Brady, Jessica Evans; Critten, Jessica

    2014-01-01

    This article is based on quantitative and qualitative research examining humanities scholars' understandings of the advantages and disadvantages of print versus electronic information resources. It explores how humanities' faculty members at Florida State University (FSU) use print and electronic resources, as well as how they perceive these…

  14. Developing Humanities Collections in the Digital Age: Exploring Humanities Faculty Engagement with Electronic and Print Resources

    Science.gov (United States)

    Kachaluba, Sarah Buck; Brady, Jessica Evans; Critten, Jessica

    2014-01-01

    This article is based on quantitative and qualitative research examining humanities scholars' understandings of the advantages and disadvantages of print versus electronic information resources. It explores how humanities' faculty members at Florida State University (FSU) use print and electronic resources, as well as how they perceive these…

  15. Human Soluble TRAIL Protein Inducing Apoptosis in Osteosarcoma Cell

    Institute of Scientific and Technical Information of China (English)

    ZHU Shaobo; YU Aixi; ZHANG Zhongning; WU Gang

    2007-01-01

    This study is to examine the effect of human recombinant soluble TRAIL (TNF-related apoptosis-inducing ligand) protein inducing apoptosis in MG-63 human osteosarcoma cells. The inhibitive rates of TRAIL to MG-63 cells were detected by MTT assay. The apoptosis induced by TRAIL in MG-63 human osteosarcoma cells was analyzed with FACS and TUNEL and the apoptotic bodies were observed by transmission electron microscope. MTT assay showed that the inhibitive rates of 500, 1 000,2 000 and 4 000 ng/mL TRAIL for 24 h were 10.1%, 24.3%,50.6% and 97.7% respectively. Flow cytometric analysis showed that after MG-63 cells were treated with 2 μg/mL TRAIL for 6 h,obvious apoptotic peak would immediately appear before diploid peak. Human soluble TRAIL protein can quickly kill MG-63 osteosarcoma cells selectively, and may have potential value for clinical treatment of osteosarcoma.

  16. The potency of human testicular stem cells

    NARCIS (Netherlands)

    Chikhovskaya, J.V.

    2013-01-01

    In this thesis, we evaluate the stem cell state of cells present in primary human testicular cell cultures as well as their origin and relation to germ or somatic lineages within testicular tissue. We conclude that human testis-derived embryonic stem cell-like (htES-like) colonies arising in primary

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

    Directory of Open Access Journals (Sweden)

    Shigeki Ohta

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

  18. Telocytes and putative stem cells in the lungs: electron microscopy, electron tomography and laser scanning microscopy.

    Science.gov (United States)

    Popescu, Laurentiu M; Gherghiceanu, Mihaela; Suciu, Laura C; Manole, Catalin G; Hinescu, Mihail E

    2011-09-01

    This study describes a novel type of interstitial (stromal) cell - telocytes (TCs) - in the human and mouse respiratory tree (terminal and respiratory bronchioles, as well as alveolar ducts). TCs have recently been described in pleura, epicardium, myocardium, endocardium, intestine, uterus, pancreas, mammary gland, etc. (see www.telocytes.com ). TCs are cells with specific prolongations called telopodes (Tp), frequently two to three per cell. Tp are very long prolongations (tens up to hundreds of μm) built of alternating thin segments known as podomers (≤ 200 nm, below the resolving power of light microscope) and dilated segments called podoms, which accommodate mitochondria, rough endoplasmic reticulum and caveolae. Tp ramify dichotomously, making a 3-dimensional network with complex homo- and heterocellular junctions. Confocal microscopy reveals that TCs are c-kit- and CD34-positive. Tp release shed vesicles or exosomes, sending macromolecular signals to neighboring cells and eventually modifying their transcriptional activity. At bronchoalveolar junctions, TCs have been observed in close association with putative stem cells (SCs) in the subepithelial stroma. SCs are recognized by their ultrastructure and Sca-1 positivity. Tp surround SCs, forming complex TC-SC niches (TC-SCNs). Electron tomography allows the identification of bridging nanostructures, which connect Tp with SCs. In conclusion, this study shows the presence of TCs in lungs and identifies a TC-SC tandem in subepithelial niches of the bronchiolar tree. In TC-SCNs, the synergy of TCs and SCs may be based on nanocontacts and shed vesicles.

  19. Stem cell differentiation and human liver disease

    Institute of Scientific and Technical Information of China (English)

    Wen-Li Zhou; Claire N Medine; Liang Zhu; David C Hay

    2012-01-01

    Human stem cells are scalable cell populations capable of cellular differentiation.This makes them a very attractive in vitro cellular resource and in theory provides unlimited amounts of primary cells.Such an approach has the potential to improve our understanding of human biology and treating disease.In the future it may be possible to deploy novel stem cell-based approaches to treat human liver diseases.In recent years,efficient hepatic differentiation from human stem cells has been achieved by several research groups including our own.In this review we provide an overview of the field and discuss the future potential and limitations of stem cell technology.

  20. Dopamine receptor repertoire of human granulosa cells

    Directory of Open Access Journals (Sweden)

    Kunz Lars

    2007-10-01

    Full Text Available Abstract Background High levels of dopamine (DA were described in human ovary and recently evidence for DA receptors in granulosa and luteal cells has been provided, as well. However, neither the full repertoire of ovarian receptors for DA, nor their specific role, is established. Human granulosa cells (GCs derived from women undergoing in vitro fertilization (IVF are an adequate model for endocrine cells of the follicle and the corpus luteum and were therefore employed in an attempt to decipher their DA receptor repertoire and functionality. Methods Cells were obtained from patients undergoing IVF and examined using cDNA-array, RT-PCR, Western blotting and immunocytochemistry. In addition, calcium measurements (with FLUO-4 were employed. Expression of two DA receptors was also examined by in-situ hybridization in rat ovary. Effects of DA on cell viability and cell volume were studied by using an ATP assay and an electronic cell counter system. Results We found members of the two DA receptor families (D1- and D2 -like associated with different signaling pathways in human GCs, namely D1 (as expected and D5 (both are Gs coupled and linked to cAMP increase and D2, D4 (Gi/Gq coupled and linked to IP3/DAG. D3 was not found. The presence of the trophic hormone hCG (10 IU/ml in the culture medium for several days did not alter mRNA (semiquantitative RT-PCR or protein levels (immunocytochemistry/Western blotting of D1,2,4,5 DA receptors. Expression of prototype receptors for the two families, D1 and D2, was furthermore shown in rat granulosa and luteal cells by in situ hybridization. Among the DA receptors found in human GCs, D2 expression was marked both at mRNA and protein levels and it was therefore further studied. Results of additional RT-PCR and Western blots showed two splice variants (D2L, D2S. Irrespective of these variants, D2 proved to be functional, as DA raised intracellular calcium levels. This calcium mobilizing effect of DA was observed

  1. Absence of C-type virus production in human leukemic B cell, T cell and null cell lines.

    Directory of Open Access Journals (Sweden)

    Ogura,Hajime

    1978-06-01

    Full Text Available Electron microscope observation of cultured human leukemic B cell, T cell and null cell lines and reverse transcriptase assay of the culture supernatants were all negative for the presence of C-type virus. Bat cell line, which propagates primate C-type viruses well, was cocultivated with the human leukemic cell lines, in the hope of amplification of virus if present. Three weeks after mixed culture, the culture supernatants were again examined for reverse transcriptase activity and the cells were tested for syncytia formation by cocultivation with rat XC, human KC and RSb cell lines. All these tests, except for the positive control using a simian sarcoma virus, were negative, suggesting that no C-type was produced from these human leukemic cell lines.

  2. The human airway epithelial basal cell transcriptome.

    Directory of Open Access Journals (Sweden)

    Neil R Hackett

    Full Text Available BACKGROUND: The human airway epithelium consists of 4 major cell types: ciliated, secretory, columnar and basal cells. During natural turnover and in response to injury, the airway basal cells function as stem/progenitor cells for the other airway cell types. The objective of this study is to better understand human airway epithelial basal cell biology by defining the gene expression signature of this cell population. METHODOLOGY/PRINCIPAL FINDINGS: Bronchial brushing was used to obtain airway epithelium from healthy nonsmokers. Microarrays were used to assess the transcriptome of basal cells purified from the airway epithelium in comparison to the transcriptome of the differentiated airway epithelium. This analysis identified the "human airway basal cell signature" as 1,161 unique genes with >5-fold higher expression level in basal cells compared to differentiated epithelium. The basal cell signature was suppressed when the basal cells differentiated into a ciliated airway epithelium in vitro. The basal cell signature displayed overlap with genes expressed in basal-like cells from other human tissues and with that of murine airway basal cells. Consistent with self-modulation as well as signaling to other airway cell types, the human airway basal cell signature was characterized by genes encoding extracellular matrix components, growth factors and growth factor receptors, including genes related to the EGF and VEGF pathways. Interestingly, while the basal cell signature overlaps that of basal-like cells of other organs, the human airway basal cell signature has features not previously associated with this cell type, including a unique pattern of genes encoding extracellular matrix components, G protein-coupled receptors, neuroactive ligands and receptors, and ion channels. CONCLUSION/SIGNIFICANCE: The human airway epithelial basal cell signature identified in the present study provides novel insights into the molecular phenotype and biology of

  3. Solar electron source and thermionic solar cell

    Directory of Open Access Journals (Sweden)

    Parham Yaghoobi

    2012-12-01

    Full Text Available Common solar technologies are either photovoltaic/thermophotovoltaic, or use indirect methods of electricity generation such as boiling water for a steam turbine. Thermionic energy conversion based on the emission of electrons from a hot cathode into vacuum and their collection by an anode is also a promising route. However, thermionic solar conversion is extremely challenging as the sunlight intensity is too low for heating a conventional cathode to thermionic emission temperatures in a practical manner. Therefore, compared to other technologies, little has been done in this area, and the devices have been mainly limited to large experimental apparatus investigated for space power applications. Based on a recently observed “Heat Trap” effect in carbon nanotube arrays, allowing their efficient heating with low-power light, we report the first compact thermionic solar cell. Even using a simple off-the-shelf focusing lens, the device delivered over 1 V across a load. The device also shows intrinsic storage capacity.

  4. 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.

  5. Fixation methods for electron microscopy of human and other liver

    Institute of Scientific and Technical Information of China (English)

    Eddie; Wisse; Filip; Braet; Hans; Duimel; Celien; Vreuls; Ger; Koek; Steven; WM; Olde; Damink; Maartje; AJ; van; den; Broek; Bart; De; Geest; Cees; HC; Dejong; Chise; Tateno; Peter; Frederik

    2010-01-01

    For an electron microscopic study of the liver,expertise and complicated,time-consuming processing of hepatic tissues and cells is needed.The interpretation of electron microscopy(EM) images requires knowledge of the liver fine structure and experience with the numerous artifacts in fixation,embedding,sectioning,contrast staining and microscopic imaging.Hence,the aim of this paper is to present a detailed summary of different methods for the preparation of hepatic cells and tissue,for the purpose of preserv...

  6. The Electronic Box Office: Humanities and Arts On the Cable.

    Science.gov (United States)

    Adler, Richard; Baer, Walter S.

    A series of essays examines the potential of cable television (CATV) for increasing the diversity and quality of television programing. Specifically, they explore what an electronic box office could do to encourage new production sources and develop new mechanisms for distributing programing in the humanities and performaing arts. The introduction…

  7. Endocannabinoids and Human Sperm Cells

    Directory of Open Access Journals (Sweden)

    Giovanna Zolese

    2010-10-01

    Full Text Available N-acylethanolamides (NAEs are naturally occurring signaling lipids consisting of amides and esters of long-chain polyunsaturated fatty acids. Usually they are present in a very small amounts in many mammalian tissues and cells, including human reproductive tracts and fluids. Recently, the presence of N-arachidonoylethanolamide (anandamide, AEA, the most characterised member of endocannabinoids, and its congeners palmitoylethanolamide (PEA and oleylethanolamide (OEA in seminal plasma, oviductal fluid, and follicular fluids was demonstrated. AEA has been shown to bind not only type-1 (CB1 and type-2 (CB2 cannabinoid receptors, but also type-1 vanilloid receptor (TRPV1, while PEA and OEA are inactive with respect to classical cannabinoid CB1 and CB2 but activate TRPV1 or peroxisome proliferator activate receptors (PPARs. This review concerns the most recent experimental data on PEA and OEA, endocannabinoid-like molecules which appear to exert their action exclusively on sperm cells with altered features, such as membrane characteristics and kinematic parameters. Their beneficial effects on these cells could suggest a possible pharmacological use of PEA and OEA on patients affected by some forms of idiopathic infertility.

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

    Science.gov (United States)

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

    2017-07-01

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

  9. ETM study of electroporation influence on cell morphology in human malignant melanoma and human primary gingival fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    Nina Skolucka; Malgorzata Daczewska; Jolanta Saczko; Agnieszka Chwilkowska; Anna Choromanska; Malgorzata Kotulska; Iwona Kaminska; Julita Kulbacka

    2011-01-01

    Objective:To estimate electroporation (EP) influence on malignant and normal cells.Methods:Two cell lines including human malignant melanoma (Me-45) and normal human gingival fibroblast (HGFs) were used. EP parameters were the following:250,1000,1750,2500 V/cm;50 μs by5 impulses for every case. The viability of cells after EP was estimated byMTT assay. The ultrastructural analysis was observed by transmission electron microscope (ZeissEM900). Results:In the current study we observed the intracellular effect followingEP on Me-45 and HGF cells. At the conditions applied, we did not observe any significant damage of mitochondrial activity in both cell lines treated byEP. Conversely, we showed thatEP in some conditions can stimulate cells to proliferation. Some changes induced byEP were only visible in electron microscopy. In fibroblast cells we observed significant changes in lower parameters ofEP (250 and1000 V/cm). After applying higher electric field intensities (2500 V/cm) we detected many vacuoles, myelin-like bodies and swallowed endoplasmic reticulum. In melanoma cells such strong pathological modifications afterEP were not observed, in comparison with control cells. The ultrastructure of both treated cell lines was changed according to the applied parameters ofEP.Conclusions:We can claim thatEP conditions are cell line dependent. In terms of the intracellular morphology, human fibroblasts are more sensitive to electric field as compared with melanoma cells. Optimal conditions should be determined for each cell line. Summarizing our study, we can conclude thatEP is not an invasive method for human normal and malignant cells. This technique can be safely applied in chemotherapy for delivering drugs into tumor cells.

  10. ETM study of electroporation influence on cell morphology in human malignant melanoma and human primary gingival fibroblast cells.

    Science.gov (United States)

    Skolucka, Nina; Daczewska, Malgorzata; Saczko, Jolanta; Chwilkowska, Agnieszka; Choromanska, Anna; Kotulska, Malgorzata; Kaminska, Iwona; Kulbacka, Julita

    2011-04-01

    To estimate electroporation (EP) influence on malignant and normal cells. Two cell lines including human malignant melanoma (Me-45) and normal human gingival fibroblast (HGFs) were used. EP parameters were the following: 250, 1 000, 1 750, 2 500 V/cm; 50 µs by 5 impulses for every case. The viability of cells after EP was estimated by MTT assay. The ultrastructural analysis was observed by transmission electron microscope (Zeiss EM 900). In the current study we observed the intracellular effect following EP on Me-45 and HGF cells. At the conditions applied, we did not observe any significant damage of mitochondrial activity in both cell lines treated by EP. Conversely, we showed that EP in some conditions can stimulate cells to proliferation. Some changes induced by EP were only visible in electron microscopy. In fibroblast cells we observed significant changes in lower parameters of EP (250 and 1 000 V/cm). After applying higher electric field intensities (2 500 V/cm) we detected many vacuoles, myelin-like bodies and swallowed endoplasmic reticulum. In melanoma cells such strong pathological modifications after EP were not observed, in comparison with control cells. The ultrastructure of both treated cell lines was changed according to the applied parameters of EP. We can claim that EP conditions are cell line dependent. In terms of the intracellular morphology, human fibroblasts are more sensitive to electric field as compared with melanoma cells. Optimal conditions should be determined for each cell line. Summarizing our study, we can conclude that EP is not an invasive method for human normal and malignant cells. This technique can be safely applied in chemotherapy for delivering drugs into tumor cells.

  11. Coupled motions direct electrons along human microsomal P450 Chains.

    Directory of Open Access Journals (Sweden)

    Christopher R Pudney

    2011-12-01

    Full Text Available Protein domain motion is often implicated in biological electron transfer, but the general significance of motion is not clear. Motion has been implicated in the transfer of electrons from human cytochrome P450 reductase (CPR to all microsomal cytochrome P450s (CYPs. Our hypothesis is that tight coupling of motion with enzyme chemistry can signal "ready and waiting" states for electron transfer from CPR to downstream CYPs and support vectorial electron transfer across complex redox chains. We developed a novel approach to study the time-dependence of dynamical change during catalysis that reports on the changing conformational states of CPR. FRET was linked to stopped-flow studies of electron transfer in CPR that contains donor-acceptor fluorophores on the enzyme surface. Open and closed states of CPR were correlated with key steps in the catalytic cycle which demonstrated how redox chemistry and NADPH binding drive successive opening and closing of the enzyme. Specifically, we provide evidence that reduction of the flavin moieties in CPR induces CPR opening, whereas ligand binding induces CPR closing. A dynamic reaction cycle was created in which CPR optimizes internal electron transfer between flavin cofactors by adopting closed states and signals "ready and waiting" conformations to partner CYP enzymes by adopting more open states. This complex, temporal control of enzyme motion is used to catalyze directional electron transfer from NADPH→FAD→FMN→heme, thereby facilitating all microsomal P450-catalysed reactions. Motions critical to the broader biological functions of CPR are tightly coupled to enzyme chemistry in the human NADPH-CPR-CYP redox chain. That redox chemistry alone is sufficient to drive functionally necessary, large-scale conformational change is remarkable. Rather than relying on stochastic conformational sampling, our study highlights a need for tight coupling of motion to enzyme chemistry to give vectorial electron

  12. Satellite cells in human skeletal muscle plasticity.

    Science.gov (United States)

    Snijders, Tim; Nederveen, Joshua P; McKay, Bryon R; Joanisse, Sophie; Verdijk, Lex B; van Loon, Luc J C; Parise, Gianni

    2015-01-01

    Skeletal muscle satellite cells are considered to play a crucial role in muscle fiber maintenance, repair and remodeling. Our knowledge of the role of satellite cells in muscle fiber adaptation has traditionally relied on in vitro cell and in vivo animal models. Over the past decade, a genuine effort has been made to translate these results to humans under physiological conditions. Findings from in vivo human studies suggest that satellite cells play a key role in skeletal muscle fiber repair/remodeling in response to exercise. Mounting evidence indicates that aging has a profound impact on the regulation of satellite cells in human skeletal muscle. Yet, the precise role of satellite cells in the development of muscle fiber atrophy with age remains unresolved. This review seeks to integrate recent results from in vivo human studies on satellite cell function in muscle fiber repair/remodeling in the wider context of satellite cell biology whose literature is largely based on animal and cell models.

  13. IMMUNORESPONSES OF HUMANIZED SCID MICE TO HUMAN LUNG CANCER CELLS

    Institute of Scientific and Technical Information of China (English)

    陈力真; 王树蕙; 张云; 王世真

    1996-01-01

    HuPBL-SCID mice were used to explore how they would response to human ttmoor cells of 801/MLC.Living 801/MLC cells appeared to be fetal to the the mice due to the production of human TNF. The huP-BL-SCID rniee did not generate any noticeable amotmt of specific human immunoglobttlin either by single immunization with living 801/MLC cells or by repeated immunization with irradiated 801/MLC cells. Our preliminary experiments with huPBL-SCID mice showed that such chimeras would he a very useful models for tumor immunological researches.

  14. Search for naive human pluripotent stem cells

    Institute of Scientific and Technical Information of China (English)

    Simone Aparecida Siqueira Fonseca; Roberta Montero Costas; Lygia Veiga Pereira

    2015-01-01

    Normal mouse pluripotent stem cells were originallyderived from the inner cell mass (ICM) of blastocystsand shown to be the in vitro equivalent of those preimplantationembryonic cells, and thus were calledembryonic stem cells (ESCs). More than a decade later,pluripotent cells were isolated from the ICM of humanblastocysts. Despite being called human ESCs, thesecells differ significantly from mouse ESCs, includingdifferent morphology and mechanisms of control ofpluripotency, suggesting distinct embryonic originsof ESCs from the two species. Subsequently, mousepluripotent stem cells were established from the ICMderivedepiblast of post-implantation embryos. Thesemouse epiblast stem cells (EpiSCs) are morphologicaland epigenetically more similar to human ESCs. Thisraised the question of whether cells from the humanICM are in a more advanced differentiation stage thantheir murine counterpart, or whether the availableculture conditions were not adequate to maintain thosehuman cells in their in vivo state, leading to a transitioninto EpiSC-like cells in vitro . More recently, novel cultureconditions allowed the conversion of human ESCs intomouse ESC-like cells called naive (or ground state)human ESCs, and the derivation of naive human ESCsfrom blastocysts. Here we will review the characteristicsof each type of pluripotent stem cells, how (andwhether) these relate to different stages of embryonicdevelopment, and discuss the potential implications ofnaive human ESCs in research and therapy.

  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. Human cytomegalovirus induces alteration of (-actin mRNA and microfilaments in human embryo fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    林茂芳; 魏国庆; 黄河; 蔡真

    2004-01-01

    Objective: To investigate the infection of human embryo fibroblast cell line HF cells by CMV as well as the effects of CMV on β-actin mRNA and microfilaments. Methods: HF cells shape was observed after the infection of CMV. RT-PCR assay was used to detect the mRNA expression of CMV immediate early (IE) gene, β-actin and GAPDH genes of HF cells infected by CMV. CMV particles and cell microfilaments were detected with electron microscope. Results: Shape of HF cell changed after the infection by CMV. HF cells infected by CMV could express IE mRNA and the expression of β-actin mRNA decreased in a time- and titer-dependent manner compared with the uninfected HF cells whose expression of GAPDH mRNA did not change much. CMV particles were found with electron microscope in the cells. Microfilaments were ruptured and shortened after the infection of CMV. Conclusion: CMV can not only infect human embryo fibroblast cells line HF cells and replicate in the cells, but can also affect the expression of β-actin mRNA and the microfilaments.

  17. Induced pluripotent stem cell lines derived from human somatic cells.

    Science.gov (United States)

    Yu, Junying; Vodyanik, Maxim A; Smuga-Otto, Kim; Antosiewicz-Bourget, Jessica; Frane, Jennifer L; Tian, Shulan; Nie, Jeff; Jonsdottir, Gudrun A; Ruotti, Victor; Stewart, Ron; Slukvin, Igor I; Thomson, James A

    2007-12-21

    Somatic cell nuclear transfer allows trans-acting factors present in the mammalian oocyte to reprogram somatic cell nuclei to an undifferentiated state. We show that four factors (OCT4, SOX2, NANOG, and LIN28) are sufficient to reprogram human somatic cells to pluripotent stem cells that exhibit the essential characteristics of embryonic stem (ES) cells. These induced pluripotent human stem cells have normal karyotypes, express telomerase activity, express cell surface markers and genes that characterize human ES cells, and maintain the developmental potential to differentiate into advanced derivatives of all three primary germ layers. Such induced pluripotent human cell lines should be useful in the production of new disease models and in drug development, as well as for applications in transplantation medicine, once technical limitations (for example, mutation through viral integration) are eliminated.

  18. Speculations on the Impact of Global Electronic Networks on Human Cognition and Human Organization.

    Science.gov (United States)

    Nilan, Michael S.

    1993-01-01

    Examines the relationship between a society's communication technology and Marshall McLuhan's concerns for human cognition, and between the technology and the ways that humans organize their societies. It is suggested that appropriate development of global electronic networks could have a positive effect on individual and organizational abilities…

  19. CD34-positive interstitial cells of the human detrusor

    DEFF Research Database (Denmark)

    Rasmussen, Helle; Hansen, Alastair; Smedts, Frank;

    2007-01-01

    Interstitial cells of Cajal (ICC) are well described in the bowel wall. They are c-kit positive and play a role as pacemaker cells. Similar c-kit-positive cells have recently been described in the human bladder. The aim of this study was to characterize interstitial cells of the bladder detrusor...... using a panel of antibodies directed against CD117/c-kit, CD34, CD31, S100, tryptase, neurofilament, NSE, Factor-VIII and GFAP. A striking finding was an interstitial type of cell which is CD34 immunoreactive (CD34-ir) but CD117/c-kit negative. The cells have a tentacular morphology, enveloping...... and intermingling with individual muscle fasicles. Morphologically and immunohistochemically, they show no neurogenic, endothelial or mast cell differentiation. Transmission electron microscopy (TEM) showed the presence of interstitial cells with a round-to-oval nucleus, sparse perinuclear cytoplasm and long...

  20. 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.

  1. Low impact to fixed cell processing aiming transmission electron microscopy

    Science.gov (United States)

    Barth, Ortrud Monika; da Silva, Marcos Alexandre Nunes; Barreto-Vieira, Debora Ferreira

    2016-01-01

    In cell culture, cell structures suffer strong impact due to centrifugation during processing for electron microscope observation. In order to minimise this effect, a new protocol was successfully developed. Using conventional reagents and equipments, it took over one week, but cell compression was reduced to none or the lowest deformation possible. PMID:27276186

  2. Ultrastructure of human neural stem/progenitor cells and neurospheres

    Institute of Scientific and Technical Information of China (English)

    Yaodong Zhao; Tianyi Zhang; Qiang Huang; Aidong Wang; Jun Dong; Qing Lan; Zhenghong Qin

    2009-01-01

    BACKGROUND: Biological and morphological characteristics of neural stern/progenitor cells (NSPCs) have been widely investigated.OBJECTIVE: To explore the ultrastructure of human embryo-derived NSPCs and neurospheres cultivated in vitro using electron microscopy.DESIGN, TIME AND SETTING: A cell biology experiment was performed at the Brain Tumor Laboratory of Soochow University, and Jiangsu Province Key Laboratory of Neuroregeneration, Nantong University between August 2007 and April 2008.MATERIALS: Human fetal brain tissue was obtained from an 8-week-old aborted fetus; serum-free Dulbecco's modified Eagle's medium/F12 culture medium was provided by Gibco, USA; scanning electron microscope was provided by Hitachi instruments, Japan; transmission electron microscope was provided by JEOL, Japan.METHODS: NSPCs were isolated from human fetal brain tissue and cultivated in serum-free Dulbecco's modified Eagle's medium/F12 culture medium. Cells were passaged every 5-7 days. After three passages, NSPCs were harvested and used for ultrastructural examination.MAIN OUTCOME MEASURES: Ultrastructural examination of human NSPCs and adjacent cells in neurospheres.RESULTS: Individual NSPCs were visible as spherical morphologies with rough surfaces under scanning electron microscope. Generally, they had large nuclei and little cytoplasm. Nuclei were frequently globular with large amounts of euchromatin and a small quantity of heterochromatin, and most NSPCs had only one nucleolus. The Golgi apparatus and endoplasmic reticulum were underdeveloped; however, autophagosomes were clearly visible. The neurospheres were made up of NSPCs and non-fixiform material inside. Between adjacent cells and at the cytoplasmic surface of apposed plasma membranes, there were vesicle-like structures. Some membrane boundaries with high permeabilities were observed between some contiguous NSPCs in neurospheres, possibly attributable to plasmalemmal fusion between adjacent cells.CONCLUSION: A large number

  3. Human Neural Cell-Based Biosensor

    Science.gov (United States)

    2013-05-28

    including incubation with factors such as SHH ) and proceed to Human Neural Progenitor Cells Dopaminergic Differentiation β-III Tubulin/TH...exposure in human embryonic stem cells. J Recept Signal Transduct Res. 2011 Jun;31(3):206-13. Gerwe BA, Angel PM, West FD, Hasneen K, Young A

  4. Dexamethasone induced ultrastructural changes in cultured human trabecular meshwork cells.

    Science.gov (United States)

    Wilson, K; McCartney, M D; Miggans, S T; Clark, A F

    1993-09-01

    Glucocorticoid-induced ocular hypertension has been demonstrated in both animals and humans. It is possible that glucocorticoid-induced changes in trabecular meshwork (TM) cells are responsible for this hypertension. In order to elaborate further the effect of glucocorticoids on the trabecular meshwork, the ultrastructural consequences of dexamethasone (DEX) treatment were examined in three different human TM cell lines. Confluent TM cells were treated with 0.1 microM of DEX for 14 days, and then processed for light, epifluorescent microscopy or transmission electron microscopy (TEM). The effect of DEX treatment on TM cell and nuclear size was quantified using computer assisted morphometrics. Morphometric analysis showed a significant increase in both TM cell and nuclear size after 14 days of DEX treatment. Epifluorescent microscopy of rhodamine-phalloidin stained, control TM cells showed the normal arrangement of stress fibers. In contrast, DEX-treated TM cells showed unusual geodesic dome-like cross-linked actin networks. Control TM cells had the normal complement and arrangement of organelles as well as electron dense inclusions and large vacuoles. DEX-treated TM cells showed stacked arrangements of smooth and rough endoplasmic reticulum, proliferation of the Golgi apparatus, pleomorphic nuclei and increased amounts of extracellular matrix material. The DEX-induced alterations observed in the present study may be an indication of the processes that are occurring in the in vivo disease process.

  5. Developmental morphology of the human fetus kidney : Observation by light and electron microscope

    OpenAIRE

    1998-01-01

    The author observed the human fetus kidney at the fetal age of 3 weeks, 5 weeks and 6 month in utero by means of light and electron microscope in order to add some new findings to the already known knowledge. Especially, the metanephros, metanephric blastema, nephrogenic zone of the cortex and blood-urine barrier which consists of glomerulus, capillary vessel, basement membrane, podocyte and mesangium cells are observed and then physiological significance of the kidney are also discussed. On ...

  6. A correlative light microscopic, transmission and scanning electron microscopic study of the dorsum of human tongue.

    Science.gov (United States)

    Boshell, J L; Wilborn, W H; Singh, B B

    1980-01-01

    The dorsum of the human tongue has three types of papillae, filiform, fungiform and circumvallate. Some investigators have studied these by light and transmission electron microscopy. Since knowledge of the morphology through studies by scanning of the morphology through studies by scanning electron microscopy (SEM) is scant, this investigation was started with the purpose of studying human tongues at different ages. One fetal tongue and portions of three tongues from newborns were removed. Additional specimens were biopsied from the anterior region of three adult tongues. Samples were processed routinely for light microscopy, transmission electron microscoy (TEM) and scanning electron microscopy (SEM). Two distinct features were evident on the fetal tongue. The first was that the surface epithelial layer of the tongue appeared to be periderm. The second was that fungiform papillae began their development earlier than filiform. At birth, the putative periderm had disappeared and a few filiform papillae were observed. On the adult tongue, filiform papillae were numerous and were comprised of two cell populations. One cell population contained numerous keratohyalin granules (KHG). The KHG were two types, eosinophilic and basophilic. Ultrastructurally, the eosinophilic granules were less electron dense and larger in size than the basophilic KHG.

  7. Characterization and functionality of proliferative human Sertoli cells.

    Science.gov (United States)

    Chui, Kitty; Trivedi, Alpa; Cheng, C Yan; Cherbavaz, Diana B; Dazin, Paul F; Huynh, Ai Lam Thu; Mitchell, James B; Rabinovich, Gabriel A; Noble-Haeusslein, Linda J; John, Constance M

    2011-01-01

    It has long been thought that mammalian Sertoli cells are terminally differentiated and nondividing postpuberty. For most previous in vitro studies immature rodent testes have been the source of Sertoli cells and these have shown little proliferative ability when cultured. We have isolated and characterized Sertoli cells from human cadaveric testes from seven donors ranging from 12 to 36 years of age. The cells proliferated readily in vitro under the optimized conditions used with a doubling time of approximately 4 days. Nuclear 5-ethynyl-2'-deoxyuridine (EdU) incorporation confirmed that dividing cells represented the majority of the population. Classical Sertoli cell ultrastructural features, lipid droplet accumulation, and immunoexpression of GATA-4, Sox9, and the FSH receptor (FSHr) were observed by electron and fluorescence microscopy, respectively. Flow cytometry revealed the expression of GATA-4 and Sox9 by more than 99% of the cells, and abundant expression of a number of markers indicative of multipotent mesenchymal cells. Low detection of endogenous alkaline phosphatase activity after passaging showed that few peritubular myoid cells were present. GATA-4 and SOX9 expression were confirmed by reverse transcription polymerase chain reaction (RT-PCR), along with expression of stem cell factor (SCF), glial cell line-derived neurotrophic factor (GDNF), and bone morphogenic protein 4 (BMP4). Tight junctions were formed by Sertoli cells plated on transwell inserts coated with fibronectin as revealed by increased transepithelial electrical resistance (TER) and polarized secretion of the immunoregulatory protein, galectin-1. These primary Sertoli cell populations could be expanded dramatically in vitro and could be cryopreserved. The results show that functional human Sertoli cells can be propagated in vitro from testicular cells isolated from adult testis. The proliferative human Sertoli cells should have important applications in studying infertility

  8. Microvesicles released from human embryonic stem cell derived-mesenchymal stem cells inhibit proliferation of leukemia cells.

    Science.gov (United States)

    Ji, Yuan; Ma, Yongbin; Chen, Xiang; Ji, Xianyan; Gao, Jianyi; Zhang, Lei; Ye, Kai; Qiao, Fuhao; Dai, Yao; Wang, Hui; Wen, Xiangmei; Lin, Jiang; Hu, Jiabo

    2017-08-01

    Human embryonic stem cell derived-mesenchymal stem cells (hESC‑MSCs) are able to inhibit proliferation of leukemia cells. Microvesicles released from human embryonic stem cell derived-mesenchymal stem cells (hESC‑MSC‑MVs) might play an important part in antitumor activity. Microvesicles were isolated by ultracentrifugation and identified under a scanning electron microscopy and transmission electron microscope separately. After 48-h cocultured with hESC‑MSCs and hESC‑MSC‑MVs, the number of K562 and HL60 was counted and tumor cell viability was measured by CCK8 assay. The expression of proteins Bcl-2 and Bax were estimated by western blotting. Transmission electron microscope and western blot analysis were adopted to evaluate the autophagy level. Results showed that both hESC‑MSCs and hESC‑MSC‑MVs inhibited proliferation of leukemia cells in a concentration-dependent manner. hESC‑MSC‑MVs reduced the ratio of Bcl/Bax, enhanced the protein level of Beclin-1 and LC3-II conversion, thus upregulating autophagy and apoptosis. In conclusion, microvesicles released from human embryonic stem cell derived-mesenchymal stem cells inhibited tumor growth and stimulated autophagy and excessive autophagy might induce apoptosis.

  9. Scanning electron microscopic assessment on surface morphology of preserved human amniotic membrane after gamma sterilisation.

    Science.gov (United States)

    Ab Hamid, Suzina Sheikh; Zahari, Nor Kamalia; Yusof, Norimah; Hassan, Asnah

    2014-03-01

    Human amniotic membrane that has been processed and sterilised by gamma irradiation is widely used as a biological dressing in surgical applications. The morphological structure of human amniotic membrane was studied under scanning electron microscopy (SEM) to assess effects of gamma radiation on human amniotic membrane following different preservation methods. The amniotic membrane was preserved by either air drying or submerged in glycerol before gamma irradiated at 15, 25 and 35 kGy. Fresh human amniotic membrane, neither preserved nor irradiated was used as the control. The surface morphology of glycerol preserved amnion was found comparable to the fresh amniotic membrane. The cells of the glycerol preserved was beautifully arranged, homogonous in size and tended to round up. The cell structure in the air dried preserved amnion seemed to be flattened and dehydrated. The effects of dehydration on intercellular channels and the microvilli on the cell surface were clearly seen at higher magnifications (10,000×). SEM revealed that the changes of the cell morphology of the glycerol preserved amnion were visible at 35 kGy while the air dried already changed at 25 kGy. Glycerol preservation method is recommended for human amniotic membrane as the cell morphological structure is maintained and radiation doses lower than 25 kGy for sterilization did not affect the appearance of the preserved amnion.

  10. Genetic instability of cell lines derived from a single human small cell carcinoma of the lung

    DEFF Research Database (Denmark)

    Engelholm, S A; Vindeløv, L L; Spang-Thomsen, M

    1985-01-01

    with different DNA content appeared. By cloning, permanent cell lines were established from the new subpopulations, whereas the original population stopped growing. The cloned cell lines were characterized by morphology, chromosomes analysis, electron microscopy and plating efficiency; the stability of the DNA......Specimens from a human small cell carcinoma of the lung were established as a cell line in vitro. Flow cytometric DNA analysis demonstrated only one tumor cell population in the parent tumor as well as in the early passages in vitro. After six passages in vitro, two new subpopulations...

  11. Cortical network from human embryonic stem cells

    OpenAIRE

    2010-01-01

    Abstract The connection of embryonic stem cell technology and developmental biology provides valuable tools to decipher the mechanisms underlying human brain development and diseases, especially among neuronal populations, that are not readily available in primary cultures. It is obviously the case of neurons forming the human cerebral cortex. In the images that are presented, the neurons were generated in vitro from human embryonic stem cells via forebrain-like progenitors. Maintained in cul...

  12. Electron Pathways through Erythrocyte Plasma Membrane in Human Physiology and Pathology: Potential Redox Biomarker?

    Directory of Open Access Journals (Sweden)

    Elena Matteucci

    2007-01-01

    Full Text Available Erythrocytes are involved in the transport of oxygen and carbon dioxide in the body. Since pH is the influential factor in the Bohr-Haldane effect, pHi is actively maintained via secondary active transports Na+/H+ exchange and HC3 -/Cl- anion exchanger. Because of the redox properties of the iron, hemoglobin generates reactive oxygen species and thus, the human erythrocyte is constantly exposed to oxidative damage. Although the adult erythrocyte lacks protein synthesis and cannot restore damaged proteins, it is equipped with high activity of protective enzymes. Redox changes in the cell initiate various signalling pathways. Plasma membrane oxido-reductases (PMORs are transmembrane electron transport systems that have been found in the membranes of all cells and have been extensively characterized in the human erythrocyte. Erythrocyte PMORs transfer reducing equivalents from intracellular reductants to extracellular oxidants, thus their most important role seems to be to enable the cell respond to changes in intra- and extra-cellular redox environments.So far the activity of erythrocyte PMORs in disease states has not been systematically investigated. This review summarizes present knowledge on erythrocyte electron transfer activity in humans (health, type 1 diabetes, diabetic nephropathy, and chronic uremia and hypothesizes an integrated model of the functional organization of erythrocyte plasma membrane where electron pathways work in parallel with transport metabolons to maintain redox homeostasis.

  13. Electron Pathways through Erythrocyte Plasma Membrane in Human Physiology and Pathology: Potential Redox Biomarker?

    Science.gov (United States)

    Matteucci, Elena; Giampietro, Ottavio

    2007-09-17

    Erythrocytes are involved in the transport of oxygen and carbon dioxide in the body. Since pH is the influential factor in the Bohr-Haldane effect, pHi is actively maintained via secondary active transports Na(+)/H(+) exchange and HC(3) (-)/Cl(-) anion exchanger. Because of the redox properties of the iron, hemoglobin generates reactive oxygen species and thus, the human erythrocyte is constantly exposed to oxidative damage. Although the adult erythrocyte lacks protein synthesis and cannot restore damaged proteins, it is equipped with high activity of protective enzymes. Redox changes in the cell initiate various signalling pathways. Plasma membrane oxido-reductases (PMORs) are transmembrane electron transport systems that have been found in the membranes of all cells and have been extensively characterized in the human erythrocyte. Erythrocyte PMORs transfer reducing equivalents from intracellular reductants to extracellular oxidants, thus their most important role seems to be to enable the cell respond to changes in intra- and extra-cellular redox environments.So far the activity of erythrocyte PMORs in disease states has not been systematically investigated. This review summarizes present knowledge on erythrocyte electron transfer activity in humans (health, type 1 diabetes, diabetic nephropathy, and chronic uremia) and hypothesizes an integrated model of the functional organization of erythrocyte plasma membrane where electron pathways work in parallel with transport metabolons to maintain redox homeostasis.

  14. Comparative electron microscopy of basophils and mast cells, in vivo and in vitro.

    Science.gov (United States)

    Eguchi, M

    1991-01-01

    We compared the fine structure and electron microscopic cytochemical findings of basophils and mast cells from humans, guinea pigs, rabbits, mice and rats. The particulate structure was the most frequently observed and most typical structure of human and rabbit basophil granules and of guinea pig mast cell granules. The most prominent feature of guinea pig basophils and murine mast cells was that the fine structure of the granules was homogeneous. The fine structure of the granules in guinea pig basophils resembled that in murine mast cells, while the fine structure of the granules of guinea pig mast cells resembled those in human and rabbit mast cells. In mouse mast cells in culture, the majority of the granules contained small vesicles, which were also observed in human basophils in culture and in mouse basophils in vivo. The degrees of cytochemical reactivity of acid mucopolysaccharides among the species were different. Peroxidase activity was positive in most basophils and in human mast cells. Among mammals, the granules of basophils and mast cells present heterogeneous fine structure. It is of interest that the basophil granules of some species resemble the mast cell granules rather than the basophil granules of other species.

  15. Effects of electronic cigarette smoking on human health.

    Science.gov (United States)

    Meo, S A; Al Asiri, S A

    2014-01-01

    Electronic cigarette smoking is gaining dramatic popularity and is steadily spreading among the adolescents, high income, urban population around the world. The aim of this study is to highlight the hazards of e-cigarette smoking on human health. In this study, we identified 38 published studies through a systematic database searches including ISI-web of science and pub-med. We searched the related literature by using the key words including Electronic cigarette, E-cigarette, E-vapers, incidence, hazards. Studies in which electronic cigarette smoking hazards was investigated were included in the study. No limitations on publication status, study design of publication were implemented. Finally we included 28 publications and remaining 10 were excluded. E-smoking can cause, nausea, vomiting, headache, dizziness, choking, burn injuries, upper respiratory tract irritation, dry cough, dryness of the eyes and mucous membrane, release of cytokines and pro-inflammatory mediators, allergic airway inflammation, decreased exhaled nitric oxide (FeNO) synthesis in the lungs, change in bronchial gene expression and risk of lung cancer. Electronic cigarettes are swiftly promoted as an alternative to conventional cigarette smoking, although its use is highly controversial. Electronic cigarettes are not a smoking cessation product. Non-scientific claims about e-cigarettes are creating confusion in public perception about e-cigarette and people believe that e-cigarettes are safe and less addictive, but its use is unsafe and hazardous to human health. E-cigarette smoking should be regulated in the same way as traditional cigarettes and must be prohibited to children and adolescents.

  16. Yeast cell-based analysis of human lactate dehydrogenase isoforms.

    Science.gov (United States)

    Mohamed, Lulu Ahmed; Tachikawa, Hiroyuki; Gao, Xiao-Dong; Nakanishi, Hideki

    2015-12-01

    Human lactate dehydrogenase (LDH) has attracted attention as a potential target for cancer therapy and contraception. In this study, we reconstituted human lactic acid fermentation in Saccharomyces cerevisiae, with the goal of constructing a yeast cell-based LDH assay system. pdc null mutant yeast (mutated in the endogenous pyruvate decarboxylase genes) are unable to perform alcoholic fermentation; when grown in the presence of an electron transport chain inhibitor, pdc null strains exhibit a growth defect. We found that introduction of the human gene encoding LDHA complemented the pdc growth defect; this complementation depended on LDHA catalytic activity. Similarly, introduction of the human LDHC complemented the pdc growth defect, even though LDHC did not generate lactate at the levels seen with LDHA. In contrast, the human LDHB did not complement the yeast pdc null mutant, although LDHB did generate lactate in yeast cells. Expression of LDHB as a red fluorescent protein (RFP) fusion yielded blebs in yeast, whereas LDHA-RFP and LDHC-RFP fusion proteins exhibited cytosolic distribution. Thus, LDHB exhibits several unique features when expressed in yeast cells. Because yeast cells are amenable to genetic analysis and cell-based high-throughput screening, our pdc/LDH strains are expected to be of use for versatile analyses of human LDH. © The Authors 2015. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  17. Electronic Document Management: A Human Resource Management Case Study

    Directory of Open Access Journals (Sweden)

    Thomas Groenewald

    2004-11-01

    Full Text Available This case study serve as exemplar regarding what can go wrong with the implementation of an electronic document management system. Knowledge agility and knowledge as capital, is outlined against the backdrop of the information society and knowledge economy. The importance of electronic document management and control is sketched thereafter. The literature review is concluded with the impact of human resource management on knowledge agility, which includes references to the learning organisation and complexity theory. The intervention methodology, comprising three phases, follows next. The results of the three phases are presented thereafter. Partial success has been achieved with improving the human efficacy of electronic document management, however the client opted to discontinue the system in use. Opsomming Die gevalle studie dien as voorbeeld van wat kan verkeerd loop met die implementering van ’n elektroniese dokumentbestuur sisteem. Teen die agtergrond van die inligtingsgemeenskap en kennishuishouding word kennissoepelheid en kennis as kapitaal bespreek. Die literatuurstudie word afgesluit met die inpak van menslikehulpbronbestuur op kennissoepelheid, wat ook die verwysings na die leerorganisasie en kompleksietydsteorie insluit. Die metodologie van die intervensie, wat uit drie fases bestaan, volg daarna. Die resultate van die drie fases word vervolgens aangebied. Slegs gedeelte welslae is behaal met die verbetering van die menslike doeltreffendheid ten opsigte van elektroniese dokumentbestuur. Die klient besluit egter om nie voort te gaan om die huidige sisteem te gebruik nie.

  18. Human hematopoietic cell culture, transduction, and analyses

    DEFF Research Database (Denmark)

    Bonde, Jesper; Wirthlin, Louisa; Kohn, Donald B;

    2008-01-01

    This unit provides methods for introducing genes into human hematopoietic progenitor cells. The Basic Protocol describes isolation of CD34(+) cells, transduction of these cells with a retroviral vector on fibronectin-coated plates, assaying the efficiency of transduction, and establishing long...

  19. Human embryonic stem cells derived by somatic cell nuclear transfer.

    Science.gov (United States)

    Tachibana, Masahito; Amato, Paula; Sparman, Michelle; Gutierrez, Nuria Marti; Tippner-Hedges, Rebecca; Ma, Hong; Kang, Eunju; Fulati, Alimujiang; Lee, Hyo-Sang; Sritanaudomchai, Hathaitip; Masterson, Keith; Larson, Janine; Eaton, Deborah; Sadler-Fredd, Karen; Battaglia, David; Lee, David; Wu, Diana; Jensen, Jeffrey; Patton, Phillip; Gokhale, Sumita; Stouffer, Richard L; Wolf, Don; Mitalipov, Shoukhrat

    2013-06-06

    Reprogramming somatic cells into pluripotent embryonic stem cells (ESCs) by somatic cell nuclear transfer (SCNT) has been envisioned as an approach for generating patient-matched nuclear transfer (NT)-ESCs for studies of disease mechanisms and for developing specific therapies. Past attempts to produce human NT-ESCs have failed secondary to early embryonic arrest of SCNT embryos. Here, we identified premature exit from meiosis in human oocytes and suboptimal activation as key factors that are responsible for these outcomes. Optimized SCNT approaches designed to circumvent these limitations allowed derivation of human NT-ESCs. When applied to premium quality human oocytes, NT-ESC lines were derived from as few as two oocytes. NT-ESCs displayed normal diploid karyotypes and inherited their nuclear genome exclusively from parental somatic cells. Gene expression and differentiation profiles in human NT-ESCs were similar to embryo-derived ESCs, suggesting efficient reprogramming of somatic cells to a pluripotent state.

  20. Analysis of Human Resources Management Strategy in China Electronic Commerce Enterprises

    Science.gov (United States)

    Shao, Fang

    The paper discussed electronic-commerce's influence on enterprise human resources management, proposed and proved the human resources management strategy which electronic commerce enterprise should adopt from recruitment strategy to training strategy, keeping talent strategy and other ways.

  1. Human Neuroepithelial Cells Express NMDA Receptors

    Directory of Open Access Journals (Sweden)

    Cappell B

    2003-11-01

    Full Text Available Abstract L-glutamate, an excitatory neurotransmitter, binds to both ionotropic and metabotropic glutamate receptors. In certain parts of the brain the BBB contains two normally impermeable barriers: 1 cerebral endothelial barrier and 2 cerebral epithelial barrier. Human cerebral endothelial cells express NMDA receptors; however, to date, human cerebral epithelial cells (neuroepithelial cells have not been shown to express NMDA receptor message or protein. In this study, human hypothalamic sections were examined for NMDA receptors (NMDAR expression via immunohistochemistry and murine neuroepithelial cell line (V1 were examined for NMDAR via RT-PCR and Western analysis. We found that human cerebral epithelium express protein and cultured mouse neuroepithelial cells express both mRNA and protein for the NMDA receptor. These findings may have important consequences for neuroepithelial responses during excitotoxicity and in disease.

  2. Effects of PVA coated nanoparticles on human immune cells.

    Science.gov (United States)

    Strehl, Cindy; Gaber, Timo; Maurizi, Lionel; Hahne, Martin; Rauch, Roman; Hoff, Paula; Häupl, Thomas; Hofmann-Amtenbrink, Margarethe; Poole, A Robin; Hofmann, Heinrich; Buttgereit, Frank

    2015-01-01

    Nanotechnology provides new opportunities in human medicine, mainly for diagnostic and therapeutic purposes. The autoimmune disease rheumatoid arthritis (RA) is often diagnosed after irreversible joint structural damage has occurred. There is an urgent need for a very early diagnosis of RA, which can be achieved by more sensitive imaging methods. Superparamagnetic iron oxide nanoparticles (SPION) are already used in medicine and therefore represent a promising tool for early diagnosis of RA. The focus of our work was to investigate any potentially negative effects resulting from the interactions of newly developed amino-functionalized amino-polyvinyl alcohol coated (a-PVA) SPION (a-PVA-SPION), that are used for imaging, with human immune cells. We analyzed the influence of a-PVA-SPION with regard to cell survival and cell activation in human whole blood in general, and in human monocytes and macrophages representative of professional phagocytes, using flow cytometry, multiplex suspension array, and transmission electron microscopy. We found no effect of a-PVA-SPION on the viability of human immune cells, but cytokine secretion was affected. We further demonstrated that the percentage of viable macrophages increased on exposure to a-PVA-SPION. This effect was even stronger when a-PVA-SPION were added very early in the differentiation process. Additionally, transmission electron microscopy analysis revealed that both monocytes and macrophages are able to endocytose a-PVA-SPION. Our findings demonstrate an interaction between human immune cells and a-PVA-SPION which needs to be taken into account when considering the use of a-PVA-SPION in human medicine.

  3. Structure of a bacterial cell surface decaheme electron conduit.

    Science.gov (United States)

    Clarke, Thomas A; Edwards, Marcus J; Gates, Andrew J; Hall, Andrea; White, Gaye F; Bradley, Justin; Reardon, Catherine L; Shi, Liang; Beliaev, Alexander S; Marshall, Matthew J; Wang, Zheming; Watmough, Nicholas J; Fredrickson, James K; Zachara, John M; Butt, Julea N; Richardson, David J

    2011-06-07

    Some bacterial species are able to utilize extracellular mineral forms of iron and manganese as respiratory electron acceptors. In Shewanella oneidensis this involves decaheme cytochromes that are located on the bacterial cell surface at the termini of trans-outer-membrane electron transfer conduits. The cell surface cytochromes can potentially play multiple roles in mediating electron transfer directly to insoluble electron sinks, catalyzing electron exchange with flavin electron shuttles or participating in extracellular intercytochrome electron exchange along "nanowire" appendages. We present a 3.2-Å crystal structure of one of these decaheme cytochromes, MtrF, that allows the spatial organization of the 10 hemes to be visualized for the first time. The hemes are organized across four domains in a unique crossed conformation, in which a staggered 65-Å octaheme chain transects the length of the protein and is bisected by a planar 45-Å tetraheme chain that connects two extended Greek key split β-barrel domains. The structure provides molecular insight into how reduction of insoluble substrate (e.g., minerals), soluble substrates (e.g., flavins), and cytochrome redox partners might be possible in tandem at different termini of a trifurcated electron transport chain on the cell surface.

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

    Directory of Open Access Journals (Sweden)

    Holger A Russ

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

  5. Solar cell evaluation using electron beam induced current with the large chamber scanning electron microscope

    Science.gov (United States)

    Wink, Tara; Kintzel, Edward; Marienhoff, Peter; Klein, Martin

    2012-02-01

    An initial study using electron beam induced current (EBIC) to evaluate solar cells has been carried out with the large chamber scanning electron microscope (LC-SEM) at the Western Kentucky University Nondestructive Analysis Center. EBIC is a scanning electron microscope technique used for the characterization of semiconductors. To facilitate our studies, we developed a Solar Amplification System (SASY) for analyzing current distribution and defects within a solar cell module. Preliminary qualitative results will be shown for a solar cell module that demonstrates the viability of the technique using the LC-SEM. Quantitative EBIC experiments will be carried out to analyze defects and minority carrier properties. Additionally, a well-focused spot of light from an LED mounted at the side of the SEM column will scan the same area of the solar cell using the LC-SEM positioning system. SASY will then output the solar efficiency to be compared with the minority carrier properties found using EBIC.

  6. Dark cells in human oral leukoplakias

    Energy Technology Data Exchange (ETDEWEB)

    Klein-Szanto, A.J.P. (Oak Ridge National Lab., TN); Sega, M.; Banoczy, J.; Albrecht, M.

    1982-01-01

    Dark basal keratinocytes, characterized by a strong affinity for basic dyes and by electron density of cytoplasm and nucleus, could be recognized in eleven oral leukoplakias. The percentage of dark cells was higher in the group comprising leukoplakias verrucosa, and erosiva (28% of the basal cells) than in the leukoplakia simplex group (10%). The presence of these cells is a good indicator of the degree of histological dysplasia and correlates well with the preneoplastic potential of these lesions.

  7. The human chromosome. Electron microscopic observations on chromatin fiber organization.

    Science.gov (United States)

    Abuelo, J G; Moore, D E

    1969-04-01

    Human lymphocytes were grown in short-term tissue culture and were arrested in metaphase with Colcemid. Their chromosomes were prepared by the Langmuir trough-critical point drying technique and were examined under the electron microscope. In addition, some chromosomes were digested with trypsin, Pronase, or DNase. The chromosomes consist entirely of tightly packed, 240 +/- 50-A chromatin fibers. Trypsin and Pronase treatments induce relaxation of fiber packing and reveal certain underlying fiber arrangements. Furthermore, trypsin treatment demonstrates that the chromatin fiber has a 25-50 A trypsin-resistant core surrounded by a trypsin-sensitive sheath. DNase digestion suggests that this core contains DNA.

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

    Science.gov (United States)

    Parks, Kelsey

    2009-01-01

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

  9. 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.

  10. Derivation of naive human embryonic stem cells.

    Science.gov (United States)

    Ware, Carol B; Nelson, Angelique M; Mecham, Brigham; Hesson, Jennifer; Zhou, Wenyu; Jonlin, Erica C; Jimenez-Caliani, Antonio J; Deng, Xinxian; Cavanaugh, Christopher; Cook, Savannah; Tesar, Paul J; Okada, Jeffrey; Margaretha, Lilyana; Sperber, Henrik; Choi, Michael; Blau, C Anthony; Treuting, Piper M; Hawkins, R David; Cirulli, Vincenzo; Ruohola-Baker, Hannele

    2014-03-25

    The naïve pluripotent state has been shown in mice to lead to broad and more robust developmental potential relative to primed mouse epiblast cells. The human naïve ES cell state has eluded derivation without the use of transgenes, and forced expression of OCT4, KLF4, and KLF2 allows maintenance of human cells in a naïve state [Hanna J, et al. (2010) Proc Natl Acad Sci USA 107(20):9222-9227]. We describe two routes to generate nontransgenic naïve human ES cells (hESCs). The first is by reverse toggling of preexisting primed hESC lines by preculture in the histone deacetylase inhibitors butyrate and suberoylanilide hydroxamic acid, followed by culture in MEK/ERK and GSK3 inhibitors (2i) with FGF2. The second route is by direct derivation from a human embryo in 2i with FGF2. We show that human naïve cells meet mouse criteria for the naïve state by growth characteristics, antibody labeling profile, gene expression, X-inactivation profile, mitochondrial morphology, microRNA profile and development in the context of teratomas. hESCs can exist in a naïve state without the need for transgenes. Direct derivation is an elusive, but attainable, process, leading to cells at the earliest stage of in vitro pluripotency described for humans. Reverse toggling of primed cells to naïve is efficient and reproducible.

  11. The NDUFB6 subunit of the mitochondrial respiratory chain complex I is required for electron transfer activity: A proof of principle study on stable and controlled RNA interference in human cell lines

    Energy Technology Data Exchange (ETDEWEB)

    Loublier, Sandrine; Bayot, Aurelien; Rak, Malgorzata; El-Khoury, Riyad; Benit, Paule [Inserm U676, Hopital Robert Debre, F-75019 Paris (France); Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris (France); Rustin, Pierre, E-mail: pierre.rustin@inserm.fr [Inserm U676, Hopital Robert Debre, F-75019 Paris (France); Universite Paris 7, Faculte de medecine Denis Diderot, IFR02 Paris (France)

    2011-10-22

    Highlights: {yields} NDUFB6 is required for activity of mitochondrial complex I in human cell lines. {yields} Lentivirus based RNA interference results in frequent off target insertions. {yields} Flp-In recombinase mediated miRNA insertion allows gene-specific extinction. -- Abstract: Molecular bases of inherited deficiencies of mitochondrial respiratory chain complex I are still unknown in a high proportion of patients. Among 45 subunits making up this large complex, more than half has unknown function(s). Understanding the function of these subunits would contribute to our knowledge on mitochondrial physiology but might also reveal that some of these subunits are not required for the catalytic activity of the complex. A direct consequence of this finding would be the reduction of the number of candidate genes to be sequenced in patients with decreased complex I activity. In this study, we tested two different methods to stably extinct complex I subunits in cultured cells. We first found that lentivirus-mediated shRNA expression frequently resulted in the unpredicted extinction of additional gene(s) beside targeted ones. This can be ascribed to uncontrolled genetic material insertions in the genome of the host cell. This approach thus appeared inappropriate to study unknown functions of a gene. Next, we found it possible to specifically extinct a CI subunit gene by direct insertion of a miR targeting CI subunits in a Flp site (HEK293 Flp-In cells). By using this strategy we unambiguously demonstrated that the NDUFB6 subunit is required for complex I activity, and defined conditions suitable to undertake a systematic and stable extinction of the different supernumerary subunits in human cells.

  12. Regulatory T Cells in Human Ovarian Cancer

    Directory of Open Access Journals (Sweden)

    Dong-Jun Peng

    2012-01-01

    Full Text Available Multiple layers of suppressive components including regulatory T (TReg cells, suppressive antigen-presenting cells, and inhibitory cytokines form suppressive networks in the ovarian cancer microenvironment. It has been demonstrated that as a major suppressive element, TReg cells infiltrate tumor, interact with several types of immune cells, and mediate immune suppression through different molecular and cellular mechanisms. In this paper, we focus on human ovarian cancer and will discuss the nature of TReg cells including their subsets, trafficking, expansion, and function. We will briefly review the development of manipulation of TReg cells in preclinical and clinical settings.

  13. 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.

  14. 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.

  15. The influence of microwave radiation on the state of chromatin in human cells

    CERN Document Server

    Shckorbatov, Y G; Grabina, V A; Kolchigin, N N; Batrakov, D O; Kalashnikov, V V; Ivanchenko, D D; Bykov, V N

    2008-01-01

    Isolated human buccal epithelium cell were irradiated by microwaves at frequency f=35 GHz and surface power density E=30 mcW/cm2. The state of chromatin in human cells was determined by methodsof light and electron microscopy. The state of cell membranes was evaluated by the method of vital indigo carmine staining. The microwave-induced condensation of chromatin in human cells was revealed. Left side circulary polarized waves induced less effect than linearly polarized radiation. The linearly polarized electromagnetic waves induced cell membrane damage revealed by the increase of cell stainability. The data obtained are discussed in connection with the mechanisms of biologica effect of electromagnetic waves.

  16. Plasma membrane proteomics of human embryonic stem cells and human embryonal carcinoma cells.

    NARCIS (Netherlands)

    Dormeyer, W.; van Hoof, D.; Braam, S.R.; Heck, A.J.R.; Mummery, C.L.; Krijgsveld, J.

    2008-01-01

    Human embryonic stem cells (hESCs) are of immense interest in regenerative medicine as they can self-renew indefinitely and can give rise to any adult cell type. Human embryonal carcinoma cells (hECCs) are the malignant counterparts of hESCs found in testis tumors. hESCs that have acquired chromosom

  17. Titanium phosphate glass microcarriers induce enhanced osteogenic cell proliferation and human mesenchymal stem cell protein expression

    Directory of Open Access Journals (Sweden)

    Nilay J Lakhkar

    2015-11-01

    Full Text Available In this study, we have developed 50- to 100-µm-sized titanium phosphate glass microcarriers (denoted as Ti5 that show enhanced proliferation of human mesenchymal stem cells and MG63 osteosarcoma cells, as well as enhanced human mesenchymal stem cell expression of bone differentiation markers, in comparison with commercially available glass microspheres at all time points. We also demonstrate that these microcarriers provide superior human mesenchymal stem cell proliferation with conventional Dulbecco’s Modified Eagle medium than with a specially developed commercial stem cell medium. The microcarrier proliferative capacity is revealed by a 24-fold increase in MG63 cell numbers in spinner flask bioreactor studies performed over a 7-day period, versus only a 6-fold increase in control microspheres under the same conditions; the corresponding values of Ti5 and control microspheres under static culture are 8-fold and 7-fold, respectively. The capability of guided osteogenic differentiation is confirmed by ELISAs for bone morphogenetic protein-2 and osteopontin, which reveal significantly greater expression of these markers, especially osteopontin, by human mesenchymal stem cells on the Ti5 microspheres than on the control. Scanning electron microscopy and confocal laser scanning microscopy images reveal favorable MG63 and human mesenchymal stem cell adhesion on the Ti5 microsphere surfaces. Thus, the results demonstrate the suitability of the developed microspheres for use as microcarriers in bone tissue engineering applications.

  18. Derivation of Human Skin Fibroblast Lines for Feeder Cells of Human Embryonic Stem Cells.

    Science.gov (United States)

    Unger, Christian; Felldin, Ulrika; Rodin, Sergey; Nordenskjöld, Agneta; Dilber, Sirac; Hovatta, Outi

    2016-02-03

    After the first derivations of human embryonic stem cell (hESC) lines on fetal mouse feeder cell layers, the idea of using human cells instead of mouse cells as feeder cells soon arose. Mouse cells bear a risk of microbial contamination, and nonhuman immunogenic proteins are absorbed from the feeders to hESCs. Human skin fibroblasts can be effectively used as feeder cells for hESCs. The same primary cell line, which can be safely used for up to 15 passages after stock preparations, can be expanded and used for large numbers of hESC derivations and cultures. These cells are relatively easy to handle and maintain. No animal facilities or animal work is needed. Here, we describe the derivation, culture, and cryopreservation procedures for research-grade human skin fibroblast lines. We also describe how to make feeder layers for hESCs using these fibroblasts.

  19. Mesenchymal stem cell like (MSCl) cells generated from human embryonic stem cells support pluripotent cell growth

    Energy Technology Data Exchange (ETDEWEB)

    Varga, Nora [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Vereb, Zoltan; Rajnavoelgyi, Eva [Department of Immunology, Medical and Health Science Centre, University of Debrecen, Debrecen (Hungary); Nemet, Katalin; Uher, Ferenc; Sarkadi, Balazs [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary); Apati, Agota, E-mail: apati@kkk.org.hu [Membrane Research Group of the Hungarian Academy of Sciences, Semmelweis University, Budapest (Hungary)

    2011-10-28

    Highlights: Black-Right-Pointing-Pointer MSC like cells were derived from hESC by a simple and reproducible method. Black-Right-Pointing-Pointer Differentiation and immunosuppressive features of MSCl cells were similar to bmMSC. Black-Right-Pointing-Pointer MSCl cells as feeder cells support the undifferentiated growth of hESC. -- Abstract: Mesenchymal stem cell like (MSCl) cells were generated from human embryonic stem cells (hESC) through embryoid body formation, and isolated by adherence to plastic surface. MSCl cell lines could be propagated without changes in morphological or functional characteristics for more than 15 passages. These cells, as well as their fluorescent protein expressing stable derivatives, efficiently supported the growth of undifferentiated human embryonic stem cells as feeder cells. The MSCl cells did not express the embryonic (Oct4, Nanog, ABCG2, PODXL, or SSEA4), or hematopoietic (CD34, CD45, CD14, CD133, HLA-DR) stem cell markers, while were positive for the characteristic cell surface markers of MSCs (CD44, CD73, CD90, CD105). MSCl cells could be differentiated toward osteogenic, chondrogenic or adipogenic directions and exhibited significant inhibition of mitogen-activated lymphocyte proliferation, and thus presented immunosuppressive features. We suggest that cultured MSCl cells can properly model human MSCs and be applied as efficient feeders in hESC cultures.

  20. A revised model for electron dosimetry in the human small intestine.

    Science.gov (United States)

    Bhuiyan, N U; Poston, J W

    2005-01-01

    In this study, the absorbed dose was calculated to the small intestine (SI) wall of an adult human from electrons in its lumen contents. The effects on dose due to variations in the lumen radius and wall-thickness also were studied. The SI model was based on values gleaned from anatomic and histologic reviews of the adult human SI. Histologic and radiological analyses of the SI suggested the microscopic intricacy of this walled organ could be avoided for dosimetric purposes and a set of concentric cylinders could be used to model the SI. The model was input into the Monte Carlo N-Particle (MCNP) version 4A computational package, which was used to simulate energy deposition in the SI by electrons of fifty discrete energies ranging 10-500 keV. The source electrons as well as all resulting particles, such as knock-on electrons, bremsstrahlung, and electrons created from bremsstrahlung interactions, were transported until the particle energies fell below the 1 keV low-energy cutoff. Detailed physics treatments for secondary photons were made. With a reasonable number of histories, appropriate variance reduction techniques were used to improve the precision of the Monte Carlo calculations. The model used very small tally regions, which ranged in thickness from 0.5 microm to 200 microm depending on the electron energy studied and tally location in the wall. Relative errors associated with these calculations were maintained at less than 5%. The large number of tally results across the wall for each of the energies studied enabled the construction of the energy-specific depth dose curves in the wall. Each of these curves was consistent with the anticipated energy deposition pattern. These curves showed that only a small fraction of the energy absorbed at the contents-mucus interface reaches the stem cell layers because the cells are located deep in the mucosa. This fraction was found to vary from 1.66 x 10(-6) to 1.21 x 10(-1) over the energy range 10-500 keV. These

  1. An Overview of Electron Acceptors in Microbial Fuel Cells.

    Science.gov (United States)

    Ucar, Deniz; Zhang, Yifeng; Angelidaki, Irini

    2017-01-01

    Microbial fuel cells (MFC) have recently received increasing attention due to their promising potential in sustainable wastewater treatment and contaminant removal. In general, contaminants can be removed either as an electron donor via microbial catalyzed oxidization at the anode or removed at the cathode as electron acceptors through reduction. Some contaminants can also function as electron mediators at the anode or cathode. While previous studies have done a thorough assessment of electron donors, cathodic electron acceptors and mediators have not been as well described. Oxygen is widely used as an electron acceptor due to its high oxidation potential and ready availability. Recent studies, however, have begun to assess the use of different electron acceptors because of the (1) diversity of redox potential, (2) needs of alternative and more efficient cathode reaction, and (3) expanding of MFC based technologies in different areas. The aim of this review was to evaluate the performance and applicability of various electron acceptors and mediators used in MFCs. This review also evaluated the corresponding performance, advantages and disadvantages, and future potential applications of select electron acceptors (e.g., nitrate, iron, copper, perchlorate) and mediators.

  2. Stem cells in the human breast

    DEFF Research Database (Denmark)

    Petersen, Ole William; Polyak, Kornelia

    2010-01-01

    The origins of the epithelial cells participating in the development, tissue homeostasis, and cancer of the human breast are poorly understood. However, emerging evidence suggests a role for adult tissue-specific stem cells in these processes. In a hierarchical manner, these generate the two main...

  3. Human hair genealogies and stem cell latency

    Directory of Open Access Journals (Sweden)

    Tavaré Simon

    2006-02-01

    Full Text Available Abstract Background Stem cells divide to reproduce themselves and produce differentiated progeny. A fundamental problem in human biology has been the inability to measure how often stem cells divide. Although it is impossible to observe every division directly, one method for counting divisions is to count replication errors; the greater the number of divisions, the greater the numbers of errors. Stem cells with more divisions should produce progeny with more replication errors. Methods To test this approach, epigenetic errors (methylation in CpG-rich molecular clocks were measured from human hairs. Hairs exhibit growth and replacement cycles and "new" hairs physically reappear even on "old" heads. Errors may accumulate in long-lived stem cells, or in their differentiated progeny that are eventually shed. Results Average hair errors increased until two years of age, and then were constant despite decades of replacement, consistent with new hairs arising from infrequently dividing bulge stem cells. Errors were significantly more frequent in longer hairs, consistent with long-lived but eventually shed mitotic follicle cells. Conclusion Constant average hair methylation regardless of age contrasts with the age-related methylation observed in human intestine, suggesting that error accumulation and therefore stem cell latency differs among tissues. Epigenetic molecular clocks imply similar mitotic ages for hairs on young and old human heads, consistent with a restart with each new hair, and with genealogies surreptitiously written within somatic cell genomes.

  4. Human neutrophils facilitate tumor cell transendothelial migration.

    LENUS (Irish Health Repository)

    Wu, Q D

    2012-02-03

    Tumor cell extravasation plays a key role in tumor metastasis. However, the precise mechanisms by which tumor cells migrate through normal vascular endothelium remain unclear. In this study, using an in vitro transendothelial migration model, we show that human polymorphonuclear neutrophils (PMN) assist the human breast tumor cell line MDA-MB-231 to cross the endothelial barrier. We found that tumor-conditioned medium (TCM) downregulated PMN cytocidal function, delayed PMN apoptosis, and concomitantly upregulated PMN adhesion molecule expression. These PMN treated with TCM attached to tumor cells and facilitated tumor cell migration through different endothelial monolayers. In contrast, MDA-MB-231 cells alone did not transmigrate. FACScan analysis revealed that these tumor cells expressed high levels of intercellular adhesion molecule-1 (ICAM-1) but did not express CD11a, CD11b, or CD18. Blockage of CD11b and CD18 on PMN and of ICAM-1 on MDA-MB-231 cells significantly attenuated TCM-treated, PMN-mediated tumor cell migration. These tumor cells still possessed the ability to proliferate after PMN-assisted transmigration. These results indicate that TCM-treated PMN may serve as a carrier to assist tumor cell transendothelial migration and suggest that tumor cells can exploit PMN and alter their function to facilitate their extravasation.

  5. Particle-in-cell Simulations with Kinetic Electrons

    Energy Technology Data Exchange (ETDEWEB)

    J.L.V. Lewandowski

    2004-02-12

    A new scheme, based on an exact separation between adiabatic and nonadiabatic electron responses, for particle-in-cell (PIC) simulations of drift-type modes is presented. The (linear and nonlinear) elliptic equations for the scalar fields are solved using a multi-grid solver. The new scheme yields linear growth rates in excellent agreement with theory and it is shown to conserve energy well into the nonlinear regime. It is also demonstrated that simulations with few electrons are reliable and accurate, suggesting that large-scale, PIC simulations with electron dynamics in toroidal geometry (e.g., tokamaks and stellarators plasmas) are within reach of present-day massively parallel supercomputers.

  6. Organic photovoltaic cells based on unconventional electron donor fullerene and electron acceptor copper hexadecafluorophthalocyanine

    Science.gov (United States)

    Yang, J. L.; Sullivan, P.; Schumann, S.; Hancox, I.; Jones, T. S.

    2012-01-01

    We demonstrate organic discrete heterojunction photovoltaic cells based on fullerene (C60) and copper hexadecafluorophthalocyanine (F16CuPc), in which the C60 and F16CuPc act as the electron donor and the electron acceptor, respectively. The C60/F16CuPc cells fabricated with conventional and inverted architectures both exhibit comparable power conversion efficiencies. Furthermore, we show that the photocurrent in both cells is generated by a conventional exciton dissociation mechanism rather than the exciton recombination mechanism recently proposed for a similar C60/F16ZnPc system [Song et al., J. Am. Chem. Soc. 132, 4554 (2010)]. These results demonstrate that new unconventional material systems are a potential way to fabricate organic photovoltaic cells with inverted as well as conventional architectures.

  7. Nano-Bio Electrochemical Interfacing-Linking Cell Biology and Micro-Electronics

    Science.gov (United States)

    Shacham-Diamand, Y.; Popovtzer, R.; Rishpon, Y.

    Integration of biological substance within electronic devices is an innovative and challenging area combining recent progress in molecular biology and micro technology. First, we introduce the concept of integrating living cells with Micro Electro Mechanical Systems (MEMS). Following a brief overview on "whole cell based biosensors" we describe the design, fabrication, and process of a biocompatible electrochemical "Lab-on-a-Chip" system. Demonstrating the application of electrochemical interfacing based whole cell bio chips, we present two different configurations: a. integration of prokaryotic cells (bacteria) for water toxicity detection, and b. integration of eukaryotic cells (human colon cancer cells) for rapid evaluation of the effectiveness of drug treatments. Both applications, with either microbes or mammalian cells integrated onto MEMS based biochips with liquid volume in the range of 100 nL-1 μL, function well and yield a detectable signal much higher than noise level after few minutes.

  8. Bone formation induced in mouse thigh by cultured human cells.

    Science.gov (United States)

    Anderson, H C; Coulter, P R

    1967-04-01

    Cultured FL human amnion cells injected intramuscularly into cortisone-conditioned mice proliferate to form discrete nodules which become surrounded by fibroblasts. Within 12 days, fibroblastic zones differentiate into cartilage which calcifies to form bone. Experiments were conducted to test the hypothesis that FL cells behave as an inductor of bone formation. In the electron microscope, FL cells were readily distinguished from surrounding fibroblasts. Transitional forms between the two cell types were not recognized. Stains for acid mucopolysaccharides emphasized the sharp boundary between metachromatic fibroblastic and cartilaginous zones and nonmetachromatic FL cells. (35)S was taken up preferentially by fibroblasts and chondrocytes and then deposited extracellularly in a manner suggesting active secretion of sulfated mucopolysaccharides. FL cells showed negligible (35)S utilization and secretion. FL cells, labeled in vitro with thymidine-(3)H, were injected and followed radioautographically, during bone formation. Nuclear label of injected FL cells did not appear in adjacent fibroblasts in quantities sufficient to indicate origin of the latter from FL cells. The minimal fibroblast nuclear labeling seen may represent reutilization of label from necrotic FL cells. It is suggested that FL cells injected into the mouse thigh induced cartilage and bone formation by host fibroblasts.

  9. Effects of stratospheric radiations on human glioblastoma cells.

    Science.gov (United States)

    Cerù, Maria Paola; Amicarelli, Fernanda; Cristiano, Loredana; Colafarina, Sabrina; Aimola, Pierpaolo; Falone, Stefano; Cinque, Benedetta; Ursini, Ornella; Moscardelli, Roberto; Ragni, Pietro

    2005-01-01

    The aim of this work was to evaluate the effect of stratospheric radiations on neural tumour cells. ADF human glioblastoma cells were hosted on a stratospheric balloon within the 2002 biological experiment campaign of the Italian Space Agency. The flight at an average height of 37 km lasted about 24 hrs. Cell morphology, number and viability, cell cycle and apoptosis, some antioxidant enzymes and proteins involved in cell cycle regulation, DNA repair and gene expression were studied. Stratospheric radiations caused a significant decrease in cell number, as well as a block of proliferation, but not apoptosis or necrosis. Radiations also induced activation and induction of some antioxidant enzymes, increase in DNA repair-related proteins (p53 and Proliferating Cell Nuclear Antigen) and variations of the transcription factors Peroxisome Proliferator-Activated Receptors. Morphologically, test cells exhibited more electron dense cytoplasm and less condensed chromatin than controls and modification of their surfaces. Our results indicate that glioblastoma cells, exposed to continuous stratospheric radiations for 24 hrs, show activation of cell cycle check point, decrease of cell number, variations of Peroxisome Proliferator-Activated Receptors and increase of Reactive Oxygen Species-scavenging enzymes.

  10. INTERACTIONS BETWEEN THE HUMAN GASTRIC CARCINOMA CELL AND THE HUMAN VASCULAR ENDOTHELIAL CELL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    Objective To definite the interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the establishment and maintenance of the tumor vascular system and the tumor hematogenous metastasis.Methods We prepared the conditioned mediums of each cell so as to study the effect of the conditioned medium on itself or others by MTT colorimetry. The comprehensive effect of interactions between two cells was determined by stratified transfilter co-culture or direct contact co-culture.Results The conditioned medium of human gastric carcinoma cell can stimulate the proliferation of the human vascular endothelial cell, but the CM of HVEC can inhibit the growth of HGCC. Both kinds of cells can inhibit the growth of itself. The ultimate comprehensive effect of the interactions between two kinds of cells was increase of total cell numbers.Conclusion There exist the complicated interactions between the human gastric carcinoma cell and the human vascular endothelial cell during the tumor angiogenesis and the tumor hematogenous metastasis. The ultimate comprehensive effect of the interactions is increase of total cells numbers and tumor volume.

  11. Fibronectin production by human mammary cells

    Energy Technology Data Exchange (ETDEWEB)

    Stampfer, M.R. (Univ. of California, Berkeley); Vlodavsky, I.; Smith, H.S.; Ford, R.; Becker, F.F.; Riggs, J.

    1981-01-01

    Human mammary cells were examined for the presence of the high-molecular-weight surface glycoprotein fibronectin. Early passage mammary epithelial cell and fibroblast cultures from both carcinomas and normal tissues were tested for the presence of cell-associated fibronectin by immunofluorescence microscopy and for the synthesis and secretion of fibronectin by specific immunoprecipitation of metabolically labeled protein. In vivo frozen sections of primary carcinomas and normal tissues were tested for the localization of fibronectin by immunofluorescence microscopy. In contrast to the extensive fibrillar networks of fibronectin found in the fibroblast cultures, the epithelial cell cultures from both tissue sources displayed a pattern of cell-associated fibronectin characterizd by powdery, punctate staining. However, the cultured epithelial cells, as well as the fibroblasts, secreted large quantities of fibronectin into the medium. Putative myoepithelial cells also displayed extensive fibrillar networks of fibronectin. The difference in cell-associated fibronectin distribution between the epithelial cells and the fibroblasts and putative myoepithelial cells provided a simple means of quantitating stromal and myoepithelial cell contamination of the mammary epithelial cells in culture. In vivo, normal tissues showed fibronectin primarily localized in the basement membrane surrounding the epithelial cells and in the stroma. Most primary carcinomas displayed powdery, punctate staining on the epithelial cells in addition to the fibronectin present in the surrounding stroma.

  12. Immortalization of human alveolar epithelial cells to investigate nanoparticle uptake.

    Science.gov (United States)

    Kemp, Sarah J; Thorley, Andrew J; Gorelik, Julia; Seckl, Michael J; O'Hare, Michael J; Arcaro, Alexandre; Korchev, Yuri; Goldstraw, Peter; Tetley, Teresa D

    2008-11-01

    Primary human alveolar type 2 (AT2) cells were immortalized by transduction with the catalytic subunit of telomerase and simian virus 40 large-tumor antigen. Characterization by immunochemical and morphologic methods demonstrated an AT1-like cell phenotype. Unlike primary AT2 cells, immortalized cells no longer expressed alkaline phosphatase, pro-surfactant protein C, and thyroid transcription factor-1, but expressed increased caveolin-1 and receptor for advanced glycation end products (RAGE). Live cell imaging using scanning ion conductance microscopy showed that the cuboidal primary AT2 cells were approximately 15 microm and enriched with surface microvilli, while the immortal AT1 cells were attenuated more than 40 microm, resembling these cells in situ. Transmission electron microscopy highlighted the attenuated morphology and showed endosomal vesicles in some immortal AT1 cells (but not primary AT2 cells) as found in situ. Particulate air pollution exacerbates cardiopulmonary disease. Interaction of ultrafine, nano-sized particles with the alveolar epithelium and/or translocation into the cardiovasculature may be a contributory factor. We hypothesized differential uptake of nanoparticles by AT1 and AT2 cells, depending on particle size and surface charge. Uptake of 50-nm and 1-microm fluorescent latex particles was investigated using confocal microscopy and scanning surface confocal microscopy of live cells. Fewer than 10% of primary AT2 cells internalized particles. In contrast, 75% immortal AT1 cells internalized negatively charged particles, while less than 55% of these cells internalized positively charged particles; charge, rather than size, mattered. The process was rapid: one-third of the total cell-associated negatively charged 50-nm particle fluorescence measured at 24 hours was internalized during the first hour. AT1 cells could be important in translocation of particles from the lung into the circulation.

  13. Scanning electron microscopy of human cortical bone failure surfaces.

    Science.gov (United States)

    Braidotti, P; Branca, F P; Stagni, L

    1997-02-01

    Undecalcified samples extracted from human femoral shafts are fractured by bending and the fracture surfaces are examined with a scanning electron microscope (SEM). The investigation is performed on both dry and wet (hydrated with a saline solution) specimens. SEM micrographs show patterns in many respects similar to those observed in fractography studies of laminated fiber-reinforced synthetic composites. In particular, dry and wet samples behave like brittle and ductile matrix laminates, respectively. An analysis carried out on the basis of the mechanisms that dominate the fracture process of laminates shows that a reasonable cortical bone model is that of a laminated composite material whose matrix is composed of extracellular noncollagenous calcified proteins, and the reinforcement is constituted by the calcified collagen fiber system.

  14. Laser printing of skin cells and human stem cells.

    Science.gov (United States)

    Koch, Lothar; Kuhn, Stefanie; Sorg, Heiko; Gruene, Martin; Schlie, Sabrina; Gaebel, Ralf; Polchow, Bianca; Reimers, Kerstin; Stoelting, Stephanie; Ma, Nan; Vogt, Peter M; Steinhoff, Gustav; Chichkov, Boris

    2010-10-01

    Laser printing based on laser-induced forward transfer (LIFT) is a new biofabrication technique for the arrangement of biological materials or living cells in well-defined patterns. In the current study, skin cell lines (fibroblasts/keratinocytes) and human mesenchymal stem cells (hMSC) were chosen for laser printing experiments due to their high potential in regeneration of human skin and new application possibilities of stem cell therapy. To evaluate the influence of LIFT on the cells, their survival rate, their proliferation and apoptotic activity, and the DNA damages and modifications of their cell surface markers were assessed and statistically evaluated over several days. The cells survived the transfer procedure with a rate of 98%  +/- 1% standard error of the mean (skin cells) and 90%  +/- 10% (hMSC), respectively. All used cell types maintain their ability to proliferate after LIFT. Further, skin cells and hMSC did not show an increase of apoptosis or DNA fragmentation. In addition, the hMSC keep their phenotype as proven by fluorescence activated cell sorting (FACS) analysis. This study demonstrates LIFT as a suitable technique for unharmed computer-controlled positioning of different cell types and a promising tool for future applications in the ex vivo generation of tissue replacements.

  15. Human spleen and red blood cells

    Science.gov (United States)

    Pivkin, Igor; Peng, Zhangli; Karniadakis, George; Buffet, Pierre; Dao, Ming

    2016-11-01

    Spleen plays multiple roles in the human body. Among them is removal of old and altered red blood cells (RBCs), which is done by filtering cells through the endothelial slits, small micron-sized openings. There is currently no experimental technique available that allows us to observe RBC passage through the slits. It was previously noticed that people without a spleen have less deformable red blood cells, indicating that the spleen may play a role in defining the size and shape of red blood cells. We used detailed RBC model implemented within the Dissipative Particle Dynamics (DPD) simulation framework to study the filter function of the spleen. Our results demonstrate that spleen indeed plays major role in defining the size and shape of the healthy human red blood cells.

  16. Electron Acceptor Materials Engineering in Colloidal Quantum Dot Solar Cells

    KAUST Repository

    Liu, Huan

    2011-07-15

    Lead sulfide colloidal quantum dot (CQD) solar cells with a solar power conversion efficiency of 5.6% are reported. The result is achieved through careful optimization of the titanium dioxide electrode that serves as the electron acceptor. Metal-ion-doped sol-gel-derived titanium dioxide electrodes produce a tunable-bandedge, well-passivated materials platform for CQD solar cell optimization. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Rotating cell culture systems for human cell culture: human trophoblast cells as a model.

    Science.gov (United States)

    Zwezdaryk, Kevin J; Warner, Jessica A; Machado, Heather L; Morris, Cindy A; Höner zu Bentrup, Kerstin

    2012-01-18

    The field of human trophoblast research aids in understanding the complex environment established during placentation. Due to the nature of these studies, human in vivo experimentation is impossible. A combination of primary cultures, explant cultures and trophoblast cell lines support our understanding of invasion of the uterine wall and remodeling of uterine spiral arteries by extravillous trophoblast cells (EVTs), which is required for successful establishment of pregnancy. Despite the wealth of knowledge gleaned from such models, it is accepted that in vitro cell culture models using EVT-like cell lines display altered cellular properties when compared to their in vivo counterparts. Cells cultured in the rotating cell culture system (RCCS) display morphological, phenotypic, and functional properties of EVT-like cell lines that more closely mimic differentiating in utero EVTs, with increased expression of genes mediating invasion (e.g. matrix metalloproteinases (MMPs)) and trophoblast differentiation. The Saint Georges Hospital Placental cell Line-4 (SGHPL-4) (kindly donated by Dr. Guy Whitley and Dr. Judith Cartwright) is an EVT-like cell line that was used for testing in the RCCS. The design of the RCCS culture vessel is based on the principle that organs and tissues function in a three-dimensional (3-D) environment. Due to the dynamic culture conditions in the vessel, including conditions of physiologically relevant shear, cells grown in three dimensions form aggregates based on natural cellular affinities and differentiate into organotypic tissue-like assemblies. The maintenance of a fluid orbit provides a low-shear, low-turbulence environment similar to conditions found in vivo. Sedimentation of the cultured cells is countered by adjusting the rotation speed of the RCCS to ensure a constant free-fall of cells. Gas exchange occurs through a permeable hydrophobic membrane located on the back of the bioreactor. Like their parental tissue in vivo, RCCS

  18. Organ-to-Cell-Scale Health Assessment Using Geographical Information System Approaches with Multibeam Scanning Electron Microscopy.

    Science.gov (United States)

    Knothe Tate, Melissa L; Zeidler, Dirk; Pereira, André F; Hageman, Daniel; Garbowski, Tomasz; Mishra, Sanjay; Gardner, Lauren; Knothe, Ulf R

    2016-07-01

    This study combines novel multibeam electron microscopy with a geographical information system approach to create a first, seamless, navigable anatomic map of the human hip and its cellular inhabitants. Using spatial information acquired by localizing relevant map landmarks (e.g. cells, blood vessels), network modeling will enable disease epidemiology studies in populations of cells inhabiting tissues and organs.

  19. Matrigel improves functional properties of primary human salivary gland cells.

    Science.gov (United States)

    Maria, Ola M; Zeitouni, Anthony; Gologan, Olga; Tran, Simon D

    2011-05-01

    Currently, there is no effective treatment available to patients with irreversible loss of functional salivary acini caused by Sjogren's syndrome or after radiotherapy for head and neck cancer. A tissue-engineered artificial salivary gland would help these patients. The graft cells for this device must establish tight junctions in addition to being of fluid-secretory nature. This study analyzed a graft source from human salivary glands (huSG) cultured on Matrigel. Cells were obtained from parotid and submandibular glands, expanded in vitro, and then plated on either Matrigel-coated (2 mg/mL) or uncoated culture dish. Immunohistochemistry, transmission electron microscopy, quantitative real-time-polymerase chain reaction, Western blot, and transepithelial electrical resistance were employed. On Matrigel, huSG cells adopted an acinar phenotype by forming three-dimensional acinar-like units (within 24 h of plating) as well as a monolayer of cells. On uncoated surfaces (plastic), huSG cells only formed monolayers of ductal cells. Both types of culture conditions allowed huSG cells to express tight junction proteins (claudin-1, -2, -3, -4; occludin; JAM-A; and ZO-1) and adequate transepithelial electrical resistance. Importantly, 99% of huSG cells on Matrigel expressed α-amylase and the water channel protein Aquaporin-5, as compared to cells on plastic. Transmission electron microscopy confirmed an acinar phenotype with many secretory granules. Matrigel increased the secretion of α-amylase two to five folds into the media, downregulated certain salivary genes, and regulated the translation of acinar proteins. This three-dimensional in vitro serum-free cell culture method allows the organization and differentiation of huSG cells into salivary cells with an acinar phenotype.

  20. Autophagy in human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Thien Tra

    Full Text Available Autophagy (macroautophagy is a degradative process that involves the sequestration of cytosolic material including organelles into double membrane vesicles termed autophagosomes for delivery to the lysosome. Autophagy is essential for preimplantation development of mouse embryos and cavitation of embryoid bodies. The precise roles of autophagy during early human embryonic development, remain however largely uncharacterized. Since human embryonic stem cells constitute a unique model system to study early human embryogenesis we investigated the occurrence of autophagy in human embryonic stem cells. We have, using lentiviral transduction, established multiple human embryonic stem cell lines that stably express GFP-LC3, a fluorescent marker for the autophagosome. Each cell line displays both a normal karyotype and pluripotency as indicated by the presence of cell types representative of the three germlayers in derived teratomas. GFP expression and labelling of autophagosomes is retained after differentiation. Baseline levels of autophagy detected in cultured undifferentiated hESC were increased or decreased in the presence of rapamycin and wortmannin, respectively. Interestingly, autophagy was upregulated in hESCs induced to undergo differentiation by treatment with type I TGF-beta receptor inhibitor SB431542 or removal of MEF secreted maintenance factors. In conclusion we have established hESCs capable of reporting macroautophagy and identify a novel link between autophagy and early differentiation events in hESC.

  1. Scanning Electron Microscopic Examination of the Extracellular Matrix in the Decellularized Mouse and Human Cochlea.

    Science.gov (United States)

    Santi, Peter A; Aldaya, Robair; Brown, Alec; Johnson, Shane; Stromback, Tyler; Cureoglu, Sebahattin; Rask-Andersen, Helge

    2016-06-01

    Decellularized tissues have been used to investigate the extracellular matrix (ECM) in a number of different tissues and species. Santi and Johnson JARO 14:3-15 (2013) first described the decellularized inner ear in the mouse, rat, and human using scanning thin-sheet laser imaging microscopy (sTSLIM). The purpose of the present investigation is to examine decellularized cochleas in the mouse and human at higher resolution using scanning electron microscopy (SEM). Fresh cochleas were harvested and decellularized using detergent extraction methods. Following decellularization, the ECM of the bone, basilar membrane, spiral limbus, and ligament remained, and all of the cells were removed from the cochlea. A number of similarities and differences in the ECM of the mouse and human were observed. A novel, spirally directed structure was present on the basilar membrane and is located at the border between Hensen and Boettcher cells. These septa-like structures formed a single row in the mouse and multiple rows in the human. The basal lamina of the stria vascularis capillaries was present and appeared thicker in the human compared with the mouse. In the mouse, numerous openings beneath the spiral prominence that previously housed the root processes of the external sulcus cells were observed but in the human there was only a single row of openings. These and other anatomical differences in the ECM between the mouse and human may reflect functional differences and/or be due to aging; however, decellularized cochleas provide a new way to examine the cochlear ECM and reveal new observations.

  2. Human embryonic stem cells for neuronal repair.

    Science.gov (United States)

    Ben-Hur, Tamir

    2006-02-01

    Human embryonic stem cells may serve as a potentially endeless source of transplantable cells to treat various neurologic disorders. Accumulating data have shown the therapeutic value of various neural precursor cell types in experimental models of neurologic diseases. Tailoring cell therapy for specific disorders requires the generation of cells that are committed to specific neural lineages. To this end, protocols were recently developed for the derivation of dopaminergic neurons, spinal motor neurons and oligodendrocytes from hESC. These protocols recapitulate normal development in culture conditions. However, a novel concept emerging from these studies is that the beneficial effect of transplanted stem cells is not only via cell replacement in damaged host tissue, but also by trophic and protective effects, as well as by an immunomodulatory effect that down-regulates detrimental brain inflammation.

  3. Novel agents inhibit human leukemic cells

    Institute of Scientific and Technical Information of China (English)

    Wei-ping YU; Juan LI

    2012-01-01

    Ouabain (OUA) and pyrithione zinc (PZ) have been proved as the potential drugs for treating acute myeloid leukemia (AML).Selected from a screening among 1040 Food and Drug Administration-approved pharmacological agents,both drugs showability to induce apoptosis of the culturing AML cells,exhibiting the poisoning effect on the cells.Studies also reveal the efficiency of the drugs in inhibiting the growth of human AML cells injected into the mice lacking of immunity and killing primary AML cells from the peripheral blood of AML patients[1].

  4. Proteasome inhibition-induces endoplasmic reticulum dysfunction and cell death of human cholangiocarcinoma cells

    Institute of Scientific and Technical Information of China (English)

    Yucel Ustundag; Steven F Bronk; Gregory J Gores

    2007-01-01

    AIM: To determine if proteasome inhibition induces apoptosis in human cholangiocarcinoma cells, and if so, to elucidate the cellular mechanisms.METHODS: Studies were performed in the human KMCH, KMBC, and Mz-ChA-1 cholangiocarcinoma, and normal rat cell lines. MG132, a peptide aldehyde, which inhibits the chymotrypsin-like activity of the proteaosome was employed for this study. Apoptosis was assessed morphologically by 4'-6-Diamidino-2-phenylindole (DAPI) nuclear staining and fluorescence microscopy. Mitochondrial membrane potential was examined using a fluorescent unquenching assay. Ultrastructural changes during cell death were examined using transmission electron microscopy (TEM). Caspase 3/7 activity was assessed using an enzymatic-based fluorescent assay. Cytosolic-free calcium concentrations were measured using Fura-2 and digitized fluorescent microscopy.RESULTS: MG132, a proteasome inhibitor, induced apoptosis in all the cholangiocarcinoma cell lines examined. In contrast, minimal cytotoxicity was observed in normal rat cholangiocytes. Apoptosis was time- and -concentration-dependent. There was no change in the mitochondrial membrane potential between treated and untreated cells. Ultrastructural examination by transmission electron microscopy displayed the classic features of apoptosis, but in addition, there was also dramatic vacuolization of the endoplasmic reticulum (ER). Unexpectedly, no increase in caspase 3/7 activity was observed in MG132 treated cells, nor did the pancaspase inhibitor, Q-VD-OPh prevent cell death. The protein synthesis inhibitor, cycloheximide, blocked apoptosis induced by proteosome inhibitor indicating that ER dysfunction was dependent upon the formation of new proteins.CONCLUSION:Proteosome inhibition induces ER dysfunction and caspase-independent cell death selectively in human cholangiocarcinoma cells. Proteasome inhibitors warrant evaluation as anticancer agents for the treatment of human cholangiocarcinoma.

  5. Flexible and wearable electronic silk fabrics for human physiological monitoring

    Science.gov (United States)

    Mao, Cuiping; Zhang, Huihui; Lu, Zhisong

    2017-09-01

    The development of textile-based devices for human physiological monitoring has attracted tremendous interest in recent years. However, flexible physiological sensing elements based on silk fabrics have not been realized. In this paper, ZnO nanorod arrays are grown in situ on reduced graphene oxide-coated silk fabrics via a facile electro-deposition method for the fabrication of silk-fabric-based mechanical sensing devices. The data show that well-aligned ZnO nanorods with hexagonal wurtzite crystalline structures are synthesized on the conductive silk fabric surface. After magnetron sputtering of gold electrodes, silk-fabric-based devices are produced and applied to detect periodic bending and twisting. Based on the electric signals, the deformation and release processes can be easily differentiated. Human arterial pulse and respiration can also be real-time monitored to calculate the pulse rate and respiration frequency, respectively. Throat vibrations during coughing and singing are detected to demonstrate the voice recognition capability. This work may not only help develop silk-fabric-based mechanical sensing elements for potential applications in clinical diagnosis, daily healthcare monitoring and voice recognition, but also provide a versatile method for fabricating textile-based flexible electronic devices.

  6. Electron microscopy in cell biology: integrating structure and function

    NARCIS (Netherlands)

    Koster, A.J.; Klumperman, J.

    2003-01-01

    Electron microscopy (EM) is at the highest-resolution limit of a spectrum of complementary morphological techniques. When combined with molecular detection methods, EM is the only technique with sufficient resolution to localize proteins to small membrane subdomains in the context of the cell. Recen

  7. Hydrogen peroxide inhibits photosynthetic electron transport in cells of cyanobacteria.

    Science.gov (United States)

    Samuilov, V D; Bezryadnov, D B; Gusev, M V; Kitashov, A V; Fedorenko, T A

    2001-06-01

    The effect of H2O2 on photosynthetic O2 evolution and photosynthetic electron transfer in cells of cyanobacteria Anabaena variabilis and Anacystis nidulans was studied. The following experiments were performed: 1) directly testing the effect of exogenous H2O2; 2) testing the effect of intracellular H2O2 generated with the use of methyl viologen (MV); 3) testing the effect of inhibiting intracellular H2O2 decomposition by salicylic acid (SA) and 3-amino-1,2,4-triazole (AT). H2O2 inhibited photosynthetic O2 evolution and light-induced reduction of p-benzoquinone (BQ) + ferricyanide (FeCy) in the Hill reaction. The I50 value for H2O2 was ~0.75 mM. Photosynthetic electron transfer in the cells treated with H2O2 was not maintained by H2O2, NH2OH, 1,5-diphenylcarbazide, tetraphenylboron, or butylated hydroxytoluene added as artificial electron donors for Photosystem (PS) II. The H2O --> CO2, H2O --> MV (involving PSII and PSI) and H2O --> BQ + FeCy (chiefly dependent on PSII) electron transfer reactions were inhibited upon incubation of the cells with MV, SA, or AT. The N,N,N,N-tetramethyl-p-phenylenediamine --> MV (chiefly dependent on PSI) electron transfer was inhibited by SA and AT but was resistant to MV. The results show that H2O2 inhibits photosynthetic electron transfer. It is unlikely that H2O2 could be a physiological electron donor in oxygenic photosynthesis.

  8. 3 CFR - Guidelines for Human Stem Cell Research

    Science.gov (United States)

    2010-01-01

    ... 3 The President 1 2010-01-01 2010-01-01 false Guidelines for Human Stem Cell Research Presidential Documents Other Presidential Documents Memorandum of July 30, 2009 Guidelines for Human Stem Cell Research..., scientifically worthy human stem cell research, including human embryonic stem cell research, to the extent...

  9. Myristoylation profiling in human cells and zebrafish

    Directory of Open Access Journals (Sweden)

    Malgorzata Broncel

    2015-09-01

    Full Text Available Human cells (HEK 293, HeLa, MCF-7 and zebrafish embryos were metabolically tagged with an alkynyl myristic acid probe, lysed with an SDS buffer and tagged proteomes ligated to multifunctional capture reagents via copper-catalyzed alkyne azide cycloaddition (CuAAC. This allowed for affinity enrichment and high-confidence identification, by delivering direct MS/MS evidence for the modification site, of 87 and 61 co-translationally myristoylated proteins in human cells and zebrafish, respectively. The data have been deposited to ProteomeXchange Consortium (Vizcaíno et al., 2014 Nat. Biotechnol., 32, 223–6 (PXD001863 and PXD001876 and are described in detail in Multifunctional reagents for quantitative proteome-wide analysis of protein modification in human cells and dynamic protein lipidation during vertebrate development׳ by Broncel et al., Angew. Chem. Int. Ed.

  10. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    Science.gov (United States)

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes. PMID:27212953

  11. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins.

    Science.gov (United States)

    Fukusumi, Hayato; Shofuda, Tomoko; Bamba, Yohei; Yamamoto, Atsuyo; Kanematsu, Daisuke; Handa, Yukako; Okita, Keisuke; Nakamura, Masaya; Yamanaka, Shinya; Okano, Hideyuki; Kanemura, Yonehiro

    2016-01-01

    Human neural progenitor cells (hNPCs) have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC) clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB) formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi). Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes.

  12. Efficient derivation and genetic modifications of human pluripotent stem cells on engineered human feeder cell lines.

    Science.gov (United States)

    Zou, Chunlin; Chou, Bin-Kuan; Dowey, Sarah N; Tsang, Kitman; Huang, Xiaosong; Liu, Cyndi F; Smith, Cory; Yen, Jonathan; Mali, Prashant; Zhang, Yu Alex; Cheng, Linzhao; Ye, Zhaohui

    2012-08-10

    Derivation of pluripotent stem cells (iPSCs) induced from somatic cell types and the subsequent genetic modifications of disease-specific or patient-specific iPSCs are crucial steps in their applications for disease modeling as well as future cell and gene therapies. Conventional procedures of these processes require co-culture with primary mouse embryonic fibroblasts (MEFs) to support self-renewal and clonal growth of human iPSCs as well as embryonic stem cells (ESCs). However, the variability of MEF quality affects the efficiencies of all these steps. Furthermore, animal sourced feeders may hinder the clinical applications of human stem cells. In order to overcome these hurdles, we established immortalized human feeder cell lines by stably expressing human telomerase reverse transcriptase, Wnt3a, and drug resistance genes in adult mesenchymal stem cells. Here, we show that these immortalized human feeders support efficient derivation of virus-free, integration-free human iPSCs and long-term expansion of human iPSCs and ESCs. Moreover, the drug-resistance feature of these feeders also supports nonviral gene transfer and expression at a high efficiency, mediated by piggyBac DNA transposition. Importantly, these human feeders exhibit superior ability over MEFs in supporting homologous recombination-mediated gene targeting in human iPSCs, allowing us to efficiently target a transgene into the AAVS1 safe harbor locus in recently derived integration-free iPSCs. Our results have great implications in disease modeling and translational applications of human iPSCs, as these engineered human cell lines provide a more efficient tool for genetic modifications and a safer alternative for supporting self-renewal of human iPSCs and ESCs.

  13. Optical and electronic loss analysis of mesoporous solar cells

    Science.gov (United States)

    Kovalsky, Anton; Burda, Clemens

    2016-07-01

    We review the art of complete optical and electronic characterization of the popular mesoporous solar cell motif. An overview is given of how the mesoporous paradigm is applied to solar cell technology, followed by a discussion on the variety of techniques available for thoroughly probing efficiency leaching mechanisms at every stage of the energy transfer pathway. Some attention is dedicated to the rising importance of computational results to augment loss analysis due to the complexity of solar cell devices, which have emergent properties that are important to account for, but difficult to measure, such as parasitic absorption.

  14. [Human pluripotent stem cell and neural differentiation].

    Science.gov (United States)

    Wataya, Takafumi; Muguruma, Keiko; Sasai, Yoshiki

    2008-10-01

    Recovery of lost brain function is an important issue in medical studies because neurons of the central nervous system (CNS) have poor potential for regeneration. Since few CNS diseases can be treated completely by medicines, regenerative therapy by using stem cells should be studied as a new type of therapeutic intervention. The efficacy of cell replacement therapy in Parkinson's disease has been well investigated. Several studies on fetal tissue transplantation have revealed that quantity and purity of transplanted cells are necessary for recovery of symptoms. SFEB (Serum-free floating culture of embryoid body-like aggregates) method is capable of inducing multi-potential CNS progenitors that can be steered to differentiate into region-specific tissues. On the basis of the existing knowledge of embryology, we have succeeded in the generating of various types of neurons such as telencephalic, cerebeller (Purkinje and granule cells), retinal (photoreceptor cells) and hypothalamic neurons. Application of this culture method to human ES (hES) cells is necessary for clinical purpose: however, poor survival of hES cells in SFEB culture might limit the possibility of using these cells for future medical applications. We found that a selective Rho-associated kinase (ROCK) inhibitor, Y-27632, markedly diminished the dissociation-induced apoptosis of hES cells and enabled the cells to form aggregates in SFEB culture. For both mouse and human ES cells, SFEB culture is a favorable method that can generate large amounts of region-specific neurons. However, stem cell-based therapy continues to face several obstacles. It is important that researchers in the basic sciences and clinical medicine should discuss these problems together to overcome both scientific and ethical issues related to stem cells.

  15. Effect of staurosporine on cycle of human gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Min-Wen Ha; Ke-Zuo Hou; Yun-Peng Liu; Yuan Yuan

    2004-01-01

    AIM: To study the effect of staurosporine (ST) on the cell cycle of human gastriccancer cell lines MGC803 and SGC7901.METHODS: Cell proliferation was evaluated by trypan blue dye exclusion method. Apoptotic morphology was observed under a transmission electron microscope. Changes of cell cycle and apoptotic peaks of cells were determined by flow cytometry. Expression of p21WAFI gene was examined using immunohistochemistry and RT-PCR.RESULTS: The growth of MGC803 and SGC7901 cells was inhibited by ST. The inhibitory concentrations against 50% cells (IC50) at 24 h and 48 h were 54 ng/ml and 23 ng/ml for MlGC803, and 61 ng/ml and 37 ng/ml for SGC7901. Typical apoptotic bodies and apoptotic peaks were observed 24 hafter cells were treated wth ST at a concentration of 200ng/ml. The percentage of cells at G0/G1 phase was decreased and that of cells at G2/M was increased significantly in the group treated wth ST at the concentrations of 40ng/ml,60 ng/ml, 100 ng/ml for 24 h, compared with the control group (P<0.01). The expression levels of p21WAFI gene in both MGC803 and SGC7901 cells were markedly up-regulated after treatment with ST.CONCLUSION: ST can cause arrest of gastric cancer cells at G2/M phase, which may be one of the mechanisms that inhibit cell proliferation and cause apoptosis in these cells.Effect of ST on cells at G2/M phase may be attributed to the up-regulattion of p21WAFI gene.

  16. T-cell response in human leishmaniasis

    DEFF Research Database (Denmark)

    Kharazmi, A; Kemp, K; Ismail, A

    1999-01-01

    In the present communication we provide evidence for the existence of a Th1/Th2 dichotomy in the T-cell response to Leishmania antigens in human leishmaniasis. Our data suggest that the pattern of IL-4 and IFN-gamma response is polarised in these patients. Lymphocytes from individuals recovered......+. Furthermore, IL-10 plays an important role in the development of post kala azar dermal leishmaniasis (PKDL) from VL. The balance between the parasitic-specific T-cell response plays an important regulatory role in determining the outcome of Leishmania infections in humans....

  17. Characterization of human pluripotent stem cells.

    Science.gov (United States)

    Gokhale, Paul J; Andrews, Peter W

    2013-12-18

    Human pluripotent stem cells (PSCs), whether embryonic stem cells or induced PSCs, offer enormous opportunities for regenerative medicine and other biomedical applications once we have developed the ability to harness their capacity for extensive differentiation. Central to this is our ability to identify and characterize such PSCs, but this is fraught with potential difficulties that arise from a tension between functional definitions of pluripotency and the more convenient use of 'markers', a problem exacerbated by ethical issues, our lack of knowledge of early human embryonic development, and differences from the mouse paradigm.

  18. Human pluripotent stem cells in contemporary medicine

    Directory of Open Access Journals (Sweden)

    S. A. Rodin

    2015-01-01

    Full Text Available Human pluripotent stem cells (hPSCs are capable of indefinite proliferation and can be differentiated into any cell type of the human body. Therefore, they are a promising source of cells for treatment of numerous degenerative diseases and injuries. Pluripotent stem cells are also associated with a number of ethical, safety and technological issues. In this review, we describe various types of hPSCs, safety issues that concern all or some types of hPSCs and methods of clinical-grade hPSC line development. Also, we discuss current and past clinical trials involving hPSCs, their outcomes and future perspectives of hPSC-based therapy. 

  19. Isolation of a hemidesmosome-rich fraction from a human squamous cell carcinoma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Hirako, Yoshiaki, E-mail: s47526a@cc.nagoya-u.ac.jp [Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Yonemoto, Yuki; Yamauchi, Tomoe [Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan); Nishizawa, Yuji; Kawamoto, Yoshiyuki [Department of Biomedical Sciences, Chubu University, 1200 Matsumoto-cho, Kasugai 487-8501 (Japan); Owaribe, Katsushi [Division of Biological Science, Graduate School of Science, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8602 (Japan)

    2014-06-10

    Hemidesmosomes are cell-to-matrix adhesion complexes anchoring keratinocytes to basement membranes. For the first time, we present a method to prepare a fraction from human cultured cells that are highly enriched in hemidesmosomal proteins. Using DJM-1 cells derived from human squamous cell carcinoma, accumulation of hemidesmosomes was observed when these cells were cultured for more than 10 days in a commercial serum-free medium without supplemental calcium. Electron microscopy demonstrated that numerous electron-dense adhesion structures were present along the basal cell membranes of DJM-1 cells cultured under the aforementioned conditions. After removing cellular materials using an ammonia solution, hemidesmosomal proteins and deposited extracellular matrix were collected and separated by electrophoresis. There were eight major polypeptides, which were determined to be plectin, BP230, BP180, integrin α6 and β4 subunits, and laminin-332 by immunoblotting and mass spectrometry. Therefore, we designated this preparation as a hemidesmosome-rich fraction. This fraction contained laminin-332 exclusively in its unprocessed form, which may account for the promotion of laminin deposition, and minimal amounts of Lutheran blood group protein, a nonhemidesmosomal transmembrane protein. This hemidesmosome-rich fraction would be useful not only for biological research on hemidesmosomes but also for developing a serum test for patients with blistering skin diseases. - Highlights: • A defined condition promoted accumulation of hemidesmosomes in human cultured cells. • A fraction isolated from the cells contained eight major polypeptides. • The polypeptides were the five major hemidesmosome proteins and laminin-332. • The cultured cells deposited laminin-332 in its unprocessed form under the condition. • We report a method to prepare a fraction highly enriched in hemidesmosome proteins.

  20. Electron tomography of HEK293T cells using scanning electron microscope-based scanning transmission electron microscopy.

    Science.gov (United States)

    You, Yun-Wen; Chang, Hsun-Yun; Liao, Hua-Yang; Kao, Wei-Lun; Yen, Guo-Ji; Chang, Chi-Jen; Tsai, Meng-Hung; Shyue, Jing-Jong

    2012-10-01

    Based on a scanning electron microscope operated at 30 kV with a homemade specimen holder and a multiangle solid-state detector behind the sample, low-kV scanning transmission electron microscopy (STEM) is presented with subsequent electron tomography for three-dimensional (3D) volume structure. Because of the low acceleration voltage, the stronger electron-atom scattering leads to a stronger contrast in the resulting image than standard TEM, especially for light elements. Furthermore, the low-kV STEM yields less radiation damage to the specimen, hence the structure can be preserved. In this work, two-dimensional STEM images of a 1-μm-thick cell section with projection angles between ±50° were collected, and the 3D volume structure was reconstructed using the simultaneous iterative reconstructive technique algorithm with the TomoJ plugin for ImageJ, which are both public domain software. Furthermore, the cross-sectional structure was obtained with the Volume Viewer plugin in ImageJ. Although the tilting angle is constrained and limits the resulting structural resolution, slicing the reconstructed volume generated the depth profile of the thick specimen with sufficient resolution to examine cellular uptake of Au nanoparticles, and the final position of these nanoparticles inside the cell was imaged.

  1. Cell pattern in adult human corneal endothelium.

    Directory of Open Access Journals (Sweden)

    Carlos H Wörner

    Full Text Available A review of the current data on the cell density of normal adult human endothelial cells was carried out in order to establish some common parameters appearing in the different considered populations. From the analysis of cell growth patterns, it is inferred that the cell aging rate is similar for each of the different considered populations. Also, the morphology, the cell distribution and the tendency to hexagonallity are studied. The results are consistent with the hypothesis that this phenomenon is analogous with cell behavior in other structures such as dry foams and grains in polycrystalline materials. Therefore, its driving force may be controlled by the surface tension and the mobility of the boundaries.

  2. Merkel cell distribution in the human eyelid

    Directory of Open Access Journals (Sweden)

    C.A. May

    2013-10-01

    Full Text Available Although Merkel cell carcinoma of the eye lid is reported frequently in the literature, only limited information exists about the distribution of Merkel cells in this tissue. Therefore, serial sections of 18 human cadaver eye lids (donors ages ranging between 63 and 97 years were stained for cytokeratin 20 in various planes. The overall appearance of Merkel cells in these samples was low and mainly located in the outer root layer of the cilia hair follicles. Merkel cells were more frequent in the middle, and almost not detectable at the nasal and temporal edges. The localization is in accordance with that of Merkel cell carcinoma, but concerning the scarce appearance within this adulthood group, a specific physiological role of these cells in the eye lid is difficult to establish.

  3. Natural killer cells in human autoimmune disorders

    Science.gov (United States)

    2013-01-01

    Natural killer (NK) cells are innate lymphocytes that play a critical role in early host defense against viruses. Through their cytolytic capacity and generation of cytokines and chemokines, NK cells modulate the activity of other components of the innate and adaptive immune systems and have been implicated in the initiation or maintenance of autoimmune responses. This review focuses on recent research elucidating a potential immunoregulatory role for NK cells in T-cell and B-cell-mediated autoimmune disorders in humans, with a particular focus on multiple sclerosis, rheumatoid arthritis, and systemic lupus erythematous. A better understanding of the contributions of NK cells to the development of autoimmunity may lead to novel therapeutic targets in these diseases. PMID:23856014

  4. Human Colon Cancer Cells Cultivated in Space

    Science.gov (United States)

    1995-01-01

    Within five days, bioreactor cultivated human colon cancer cells (shown) grown in Microgravity on the STS-70 mission in 1995, had grown 30 times the volume of the control specimens on Earth. The samples grown in space had a higher level of cellular organization and specialization. Because they more closely resemble tumors found in the body, microgravity grown cell cultures are ideal for research purposes.

  5. Quercetin Inhibits Cell Migration and Invasion in Human Osteosarcoma Cells

    Directory of Open Access Journals (Sweden)

    Haifeng Lan

    2017-09-01

    Full Text Available Background/Aims: Osteosarcoma is a malignant tumor associated with high mortality; however, no effective therapies for the disease have been developed. Several studies have focused on elucidating the pathogenesis of osteosarcoma and have aimed to develop novel therapies for the disease. Quercetin is a vital dietary flavonoid that has been shown to have a variety of anticancer effects, as it induces cell cycle arrest, apoptosis, and differentiation and is involved in cell adhesion, metastasis and angiogenesis. Herein, we aimed to investigate the effects of quercetin on osteosarcoma migration and invasion in vitro and in vivo and to explore the molecular mechanisms underlying its effects on osteosarcoma migration and invasion. Methods: Cell viability, cell cycle activity and cell apoptosis were measured using CCK-8 assay and flow cytometry, and cell migration and invasion were evaluated by wound healing and transwell assays, respectively. The mRNA and protein expression levels of several proteins of interest were assessed by real-time quantitative PCR and western blotting, respectively. Moreover, a nude mouse model of human osteosarcoma lung metastasis was established to assess the anti-metastatic effects of quercetin in vivo. Results: We noted no significant differences in cell cycle activity and apoptosis between HOS and MG63 cells and control cells. Treatment with quercetin significantly attenuated cell migration and invasion in HOS and MG63 cells compared with treatment with control medium. Moreover HIF-1α, VEGF, MMP2, and MMP9 mRNA and protein expression levels were significantly downregulated in HOS cells treated with quercetin compared with HOS cells treated with controls. Additionally, treatment with quercetin attenuated metastatic lung tumor formation and growth in the nude mouse model of osteosarcoma compared with treatment with controls. Conclusion: Our findings regarding the inhibitory effects of quercetin on cell migration and

  6. Human Mammary Luminal Epithelial Cells Contain Progenitors to Myoepithelial Cells

    Energy Technology Data Exchange (ETDEWEB)

    Pechoux, Christine; Gudjonsson, Thorarinn; Ronnov-Jessen, Lone; Bissell, Mina J; Petersen, Ole

    1999-02-01

    The origin of the epithelial and myoepithelial cells in the human breast has not been delineated. In this study we have addressed whether luminal epithelial cells and myoepithelial cells are vertically connected, i.e., whether one is the precursor for the other. We used a primary culture assay allowing preservation of basic phenotypic traits of luminal epithelial and myoepithelial cells in culture. The two cell types were then separated immunomagnetically using antibodies directed against lineage-specific cell surface antigens into at best 100% purity. The cellular identity was ascertained by cytochemistry, immunoblotting, and 2-D gel electrophoresis. Luminal epithelial cells were identified by strong expression of cytokeratins 18 and 19 while myoepithelial cells were recognized by expression of vimentin and {alpha}-smooth muscle actin. We used a previously devised culture medium (CDM4) that allows vigorous expansion of proliferative myoepithelial cells and also devised a medium (CDM6) that allowed sufficient expansion of differentiated luminal epithelial cells based on addition of hepatocyte growth factor/scatter factor. The two different culture media supported each lineage for at least five passages without signs of interconversion. We used parallel cultures where we switched culture media, thus testing the ability of each lineage to convert to the other. Whereas the myoepithelial lineage showed no signs of interconversion, a subset of luminal epithelial cells, gradually, but distinctly, converted to myoepithelial cells. We propose that in the mature human breast, it is the luminal epithelial cell compartment that gives rise to myoepithelial cells rather than the other way around.

  7. Genetic Manipulation of Human Embryonic Stem Cells.

    Science.gov (United States)

    Eiges, Rachel

    2016-01-01

    One of the great advantages of embryonic stem (ES) cells over other cell types is their accessibility to genetic manipulation. They can easily undergo genetic modifications while remaining pluripotent, and can be selectively propagated, allowing the clonal expansion of genetically altered cells in culture. Since the first isolation of ES cells in mice, many effective techniques have been developed for gene delivery and manipulation of ES cells. These include transfection, electroporation, and infection protocols, as well as different approaches for inserting, deleting, or changing the expression of genes. These methods proved to be extremely useful in mouse ES cells, for monitoring and directing differentiation, discovering unknown genes, and studying their function, and are now being extensively implemented in human ES cells (HESCs). This chapter describes the different approaches and methodologies that have been applied for the genetic manipulation of HESCs and their applications. Detailed protocols for generating clones of genetically modified HESCs by transfection, electroporation, and infection will be described, with special emphasis on the important technical details that are required for this purpose. All protocols are equally effective in human-induced pluripotent stem (iPS) cells.

  8. Data-driven human rights: using the electronic health record to promote human rights in jail.

    Science.gov (United States)

    Glowa-Kollisch, Sarah; Andrade, Kelly; Stazesky, Richard; Teixeira, Paul; Kaba, Fatos; Macdonald, Ross; Rosner, Zachary; Selling, Daniel; Parsons, Amanda; Venters, Homer

    2014-06-14

    The electronic health record (EHR) is a commonplace innovation designed to promote efficiency, quality, and continuity of health services. In the New York City jail system, we implemented an EHR across 12 jails between 2008 and 2011. During the same time, our work increasingly focused on the importance of human rights as an essential element to the provision of medical and mental health care for our patients. Consequently, we made major modifications to the EHR to allow for better surveillance of vulnerable populations and enable reporting and analysis of patterns of abuse, neglect, and other patient concerns related to human rights. These modifications have improved our ability to find and care for patients injured in jail and those with mental health exacerbations. More work is needed, however, to optimize the potential of the EHR as a tool to promote human rights among patients in jail.

  9. Enriched retinal ganglion cells derived from human embryonic stem cells

    Science.gov (United States)

    Gill, Katherine P.; Hung, Sandy S. C.; Sharov, Alexei; Lo, Camden Y.; Needham, Karina; Lidgerwood, Grace E.; Jackson, Stacey; Crombie, Duncan E.; Nayagam, Bryony A.; Cook, Anthony L.; Hewitt, Alex W.; Pébay, Alice; Wong, Raymond C. B.

    2016-01-01

    Optic neuropathies are characterised by a loss of retinal ganglion cells (RGCs) that lead to vision impairment. Development of cell therapy requires a better understanding of the signals that direct stem cells into RGCs. Human embryonic stem cells (hESCs) represent an unlimited cellular source for generation of human RGCs in vitro. In this study, we present a 45-day protocol that utilises magnetic activated cell sorting to generate enriched population of RGCs via stepwise retinal differentiation using hESCs. We performed an extensive characterization of these stem cell-derived RGCs by examining the gene and protein expressions of a panel of neural/RGC markers. Furthermore, whole transcriptome analysis demonstrated similarity of the hESC-derived RGCs to human adult RGCs. The enriched hESC-RGCs possess long axons, functional electrophysiological profiles and axonal transport of mitochondria, suggestive of maturity. In summary, this RGC differentiation protocol can generate an enriched population of functional RGCs from hESCs, allowing future studies on disease modeling of optic neuropathies and development of cell therapies. PMID:27506453

  10. Human ES cells: starting culture from frozen cells.

    Science.gov (United States)

    Trish, Erin; Dimos, John; Eggan, Kevin

    2006-11-09

    Here we demonstrate how our lab begins a HuES human embryonic stem cell line culture from a frozen stock. First, a one to two day old ten cm plate of approximately one (to two) million irradiated mouse embryonic fibroblast feeder cells is rinsed with HuES media to remove residual serum and cell debris, and then HuES media added and left to equilibrate in the cell culture incubator. A frozen vial of cells from long term liquid nitrogen storage or a -80 C freezer is sourced and quickly submerged in a 37 C water bath for quick thawing. Cells in freezing media are then removed from the vial and placed in a large volume of HuES media. The large volume of HuES media facilitates removal of excess serum and DMSO, which can cause HuES human embryonic stem cells to differentiate. Cells are gently spun out of suspension, and then re-suspended in a small volume of fresh HuES media that is then used to seed the MEF plate. It is considered important to seed the MEF plate by gently adding the HuES cells in a drop wise fashion to evenly disperse them throughout the plate. The newly established HuES culture plate is returned to the incubator for 48 hrs before media is replaced, then is fed every 24 hours thereafter.

  11. Sodium Valproate Induces Cell Senescence in Human Hepatocarcinoma Cells

    Directory of Open Access Journals (Sweden)

    Hong-Mei An

    2013-12-01

    Full Text Available Hepatocarcinogenesis is associated with epigenetic changes, including histone deacetylases (HDACs. Epigenetic modulation by HDAC inhibition is a potentially valuable approach for hepatocellular carcinoma treatment. In present study, we evaluated the anticancer effects of sodium valproate (SVP, a known HDAC inhibitor, in human hepatocarcinoma cells. The results showed SVP inhibited the proliferation of Bel-7402 cells in a dose-dependent manner. Low dose SVP treatment caused a large and flat morphology change, positive SA-β-gal staining, and G0/G1 phase cell cycle arrest in human hepatocarcinoma cells. Low dose SVP treatment also increased acetylation of histone H3 and H4 on p21 promoter, accompanied by up-regulation of p21 and down-regulation of RB phosphorylation. These observations suggested that a low dose of SVP could induce cell senescence in hepatocarcinoma cells, which might correlate with hyperacetylation of histone H3 and H4, up-regulation of p21, and inhibition of RB phosphorylation. Since the effective concentration inducing cell senescence in hepatocarcinoma cells is clinically available, whether a clinical dose of SVP could induce cell senescence in clinical hepatocarcinoma is worthy of further study.

  12. Human embryonic stem cell lines model experimental human cytomegalovirus latency.

    Science.gov (United States)

    Penkert, Rhiannon R; Kalejta, Robert F

    2013-05-28

    Herpesviruses are highly successful pathogens that persist for the lifetime of their hosts primarily because of their ability to establish and maintain latent infections from which the virus is capable of productively reactivating. Human cytomegalovirus (HCMV), a betaherpesvirus, establishes latency in CD34(+) hematopoietic progenitor cells during natural infections in the body. Experimental infection of CD34(+) cells ex vivo has demonstrated that expression of the viral gene products that drive productive infection is silenced by an intrinsic immune defense mediated by Daxx and histone deacetylases through heterochromatinization of the viral genome during the establishment of latency. Additional mechanistic details about the establishment, let alone maintenance and reactivation, of HCMV latency remain scarce. This is partly due to the technical challenges of CD34(+) cell culture, most notably, the difficulty in preventing spontaneous differentiation that drives reactivation and renders them permissive for productive infection. Here we demonstrate that HCMV can establish, maintain, and reactivate in vitro from experimental latency in cultures of human embryonic stem cells (ESCs), for which spurious differentiation can be prevented or controlled. Furthermore, we show that known molecular aspects of HCMV latency are faithfully recapitulated in these cells. In total, we present ESCs as a novel, tractable model for studies of HCMV latency.

  13. Probing Battery Chemistry with Liquid Cell Electron Energy Loss Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Unocic, Raymond R.; Baggetto, Loic; Veith, Gabriel M.; Aguiar, Jeffery A.; Unocic, Kinga A.; Sacci, Robert L.; Dudney, Nancy J.; More, Karren L.

    2015-11-25

    We demonstrate the ability to apply electron energy loss spectroscopy (EELS) to follow the chemistry and oxidation states of LiMn2O4 and Li4Ti5O12 battery electrodes within a battery solvent. The use and importance of in situ electrochemical cells coupled with a scanning/transmission electron microscope (S/TEM) has expanded and been applied to follow changes in battery chemistry during electrochemical cycling. Furthermore, we discuss experimental parameters that influence measurement sensitivity and provide a framework to apply this important analytical method to future in situ electrochemical studies.

  14. Cytotoxic effects of composite dust on human bronchial epithelial cells.

    Science.gov (United States)

    Cokic, Stevan M; Hoet, Peter; Godderis, Lode; Wiemann, Martin; Asbach, Christof; Reichl, Franz X; De Munck, Jan; Van Meerbeek, Bart; Van Landuyt, Kirsten L

    2016-12-01

    Previous research revealed that during routine abrasive procedures like polishing, shaping or removing of composites, high amounts of respirable dust particles (composite dust particles on bronchial epithelium cells. Composite dust of five commercial composites (one nano-composite, two nano-hybrid and two hybrid composites) was generated following a clinically relevant protocol. Polymerized composite samples were cut with a rough diamond bur (grain size 100μm, speed 200,000rpm) and all composite dust was collected in a sterile chamber. Human bronchial epithelial cells (16HBE14o-) were exposed to serially diluted suspensions of composite dust in cell culture medium at concentrations between 1.1 and 3.3mg/ml. After 24h-exposure, cell viability and membrane integrity were assessed by the WST-1 and the LDH leakage assay, respectively. The release of IL-1β and IL-6 was evaluated. The composite dust particles were characterized by transmission electron microscopy and by dynamic and electrophoretic light scattering. Neither membrane damage nor release of IL-1β was detected over the complete concentration range. However, metabolic activity gradually declined for concentrations higher than 660μg/ml and the release of IL-6 was reduced when cells were exposed to the highest concentrations of dust. Composite dust prepared by conventional dental abrasion methods only affected human bronchial epithelial cells in very high concentrations. Copyright © 2016 The Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

  15. [Immune system evolution. (From cells to humans)].

    Science.gov (United States)

    Belek, A S

    1992-01-01

    The great variety of cells and molecules observed in the mammalian immune system can be explained by stepwise acquisition of them during phylogeny. Self/nonself discrimination and cell-mediated immunity have been present since the early stages of evolution. Although some inducible antimicrobial molecules have been demonstrated in invertebrates, immunoglobulins appear in vertebrates. T and B cell diversity, development of the lymphoid organs, MHC molecules, complement and cytokines are the characteristics that appear through the evolution of vertebrates. Further knowledge that will be obtained from phylogenetic studies will improve our understanding of the immune system of human.

  16. Centre for human development, stem cells & regeneration.

    Science.gov (United States)

    Oreffo, Richard O C

    2014-01-01

    The Centre for Human Development, Stem Cells and Regeneration (CHDSCR) was founded in 2004 as a cross-disciplinary research and translational program within the Faculty of Medicine at the University of Southampton. The Centre undertakes fundamental research into early development and stem cells together with applied translational research for patient benefit. The Centre has vibrant and thriving multidisciplinary research programs that harness the translational strength of the Faculty together with an innovative Stem Cell PhD program, outstanding clinical infrastructure and enterprise to deliver on this vision.

  17. Biobanking human embryonic stem cell lines

    DEFF Research Database (Denmark)

    Holm, Søren

    2016-01-01

    Stem cell banks curating and distributing human embryonic stem cells have been established in a number of countries and by a number of private institutions. This paper identifies and critically discusses a number of arguments that are used to justify the importance of such banks in policy...... are curiously absent from the particular stem cell banking policy discourse. This to some extent artificially isolates this discourse from the broader discussions about the flows of reproductive materials and tissues in modern society, and such isolation may lead to the interests of important actors being...

  18. Fullerene derivatives as electron acceptors for organic photovoltaic cells.

    Science.gov (United States)

    Mi, Dongbo; Kim, Ji-Hoon; Kim, Hee Un; Xu, Fei; Hwang, Do-Hoon

    2014-02-01

    Energy is currently one of the most important problems humankind faces. Depletion of traditional energy sources such as coal and oil results in the need to develop new ways to create, transport, and store electricity. In this regard, the sun, which can be considered as a giant nuclear fusion reactor, represents the most powerful source of energy available in our solar system. For photovoltaic cells to gain widespread acceptance as a source of clean and renewable energy, the cost per watt of solar energy must be decreased. Organic photovoltaic cells, developed in the past two decades, have potential as alternatives to traditional inorganic semiconductor photovoltaic cells, which suffer from high environmental pollution and energy consumption during production. Organic photovoltaic cells are composed of a blended film of a conjugated-polymer donor and a soluble fullerene-derivative acceptor sandwiched between a poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)-coated indium tin oxide positive electrode and a low-work-function metal negative electrode. Considerable research efforts aim at designing and synthesizing novel fullerene derivatives as electron acceptors with up-raised lowest unoccupied molecular orbital energy, better light-harvesting properties, higher electron mobility, and better miscibility with the polymer donor for improving the power conversion efficiency of the organic photovoltaic cells. In this paper, we systematically review novel fullerene acceptors synthesized through chemical modification for enhancing the photovoltaic performance by increasing open-circuit voltage, short-circuit current, and fill factor, which determine the performance of organic photovoltaic cells.

  19. Cell filling in gravure printing for printed electronics.

    Science.gov (United States)

    Cen, Jialiang; Kitsomboonloha, Rungrot; Subramanian, Vivek

    2014-11-18

    Highly scaled direct gravure is a promising printing technique for printed electronics due to its large throughput, high resolution, and simplicity. Gravure can print features in the single micron range at printing speeds of ∼1 m/s by using an optimized cell geometry and optimized printing conditions. The filling of the cells on the gravure cylinder is a critical process, since the amount of ink in the cells strongly impacts printed feature size and quality. Therefore, an understanding of cell filling is crucial to make highly scaled gravure printed electronics viable. In this work we report a novel experimental setup to investigate the filling process in real time, coupled with numerical simulations to gain insight into the experimental observations. By varying viscosity and filling speed, we ensure that the dimensionless capillary number is a good indicator of filling regime in real gravure printing. In addition, we also examine the effect of cell size on filling as this is important for increasing printing resolution. In the light of experimental and simulation results, we are able to rationalize the dominant failure in the filling process, i.e., air entrapment, which is caused by contact line pinning and interface deformation over the cell opening.

  20. Quantitative electron microscopic analysis of the epithelium of normal human alveolar mucosa.

    Science.gov (United States)

    Bernimoulin, J P; Schroeder, H E

    1977-05-31

    The epithelium of normal human alveolar mucosa originating from the anterior vestibulum was subjected to stereologic analysis. Eight biopsies were collected half-way between the muco gingival junction and the vestibular fornix from 20 to 50 year-old females, and processed for light and electron microscopy. At two levels of magnification, electron micrographs were sampled from four artificially selected strata in regions of epithelial ridges. Stereologic point counting based on a computer-aided system for analyzing stratified epithelia served for examining a total of about 860 electron micrographs. The alveolar epithelium was 0.26 mm thick, occasionally interdigitated by short, slender connective tissue papillae, and consisted of (1) a narrow basal and suprabasal, and (2) a broad spinous and surface compartment. It displayed a differentiation pattern which, in most subjects studied, was similar to that of normal human buccal epithelium, however, on the average, produced less mature surface cells. This pattern was expressed mainly by a density increase of cytoplasmic filaments (98 A in diameter), a concomitant decrease of the cytoplasmic ground substance, the formation of dark-cored membrane coating granules, and invividually variable amounts of glycogen deposition. In some subjects, a mixed differentiation pattern was found. The structural organization of alveolar epithelium, in analogy to cheek epithelium, was compatible with the function of distensibility.

  1. Advances in human B cell phenotypic profiling

    Directory of Open Access Journals (Sweden)

    Denise A Kaminski

    2012-10-01

    Full Text Available To advance our understanding and treatment of disease, research immunologists have been called-upon to place more centralized emphasis on impactful human studies. Such endeavors will inevitably require large-scale study execution and data management regulation (Big Biology, necessitating standardized and reliable metrics of immune status and function. A well-known example setting this large-scale effort in-motion is identifying correlations between eventual disease outcome and T lymphocyte phenotype in large HIV-patient cohorts using multiparameter flow cytometry. However, infection, immunodeficiency, and autoimmunity are also characterized by correlative and functional contributions of B lymphocytes, which to-date have received much less attention in the human Big Biology enterprise. Here, we review progress in human B cell phenotyping, analysis, and bioinformatics tools that constitute valuable resources for the B cell research community to effectively join in this effort.

  2. Human plasma cells express granzyme B.

    Science.gov (United States)

    Xu, Wei; Narayanan, Priya; Kang, Ning; Clayton, Sandra; Ohne, Yoichiro; Shi, Peiqing; Herve, Marie-Cecile; Balderas, Robert; Picard, Capucine; Casanova, Jean-Laurent; Gorvel, Jean-Pierre; Oh, Sangkon; Pascual, Virginia; Banchereau, Jacques

    2014-01-01

    While studying the plasma cell (PC) compartment in human tonsils, we identified that immunoglobulin kappa or lambda chain-expressing PCs are the main cells expressing granzyme B (GrzB). In vitro studies revealed that activated B cells differentiated into GrzB-expressing PCs when co-cultured with macrophages and follicular helper T cells. This effect could be reproduced on combined stimulation of IL-15 (produced by macrophages) and IL-21 (produced by T follicular helper cells) in a STAT3-dependent manner. Whereas IL-21 triggers the transcription of mRNA of GrzB, IL-15 synergizes the translation of GrzB proteins. The precise role of GrzB in PC biology remains to be understood and studies in mice will not help as their PCs do not express GrzB.

  3. Human CD56bright NK Cells

    DEFF Research Database (Denmark)

    Michel, Tatiana; Poli, Aurélie; Cuapio, Angelica

    2016-01-01

    Human NK cells can be subdivided into various subsets based on the relative expression of CD16 and CD56. In particular, CD56(bright)CD16(-/dim) NK cells are the focus of interest. They are considered efficient cytokine producers endowed with immunoregulatory properties, but they can also become...... cytotoxic upon appropriate activation. These cells were shown to play a role in different disease states, such as cancer, autoimmunity, neuroinflammation, and infection. Although their phenotype and functional properties are well known and have been extensively studied, their lineage relationship with other...... NK cell subsets is not fully defined, nor is their precise hematopoietic origin. In this article, we summarize recent studies about CD56(bright) NK cells in health and disease and briefly discuss the current controversies surrounding them....

  4. Human embryonic stem cells: preclinical perspectives

    Directory of Open Access Journals (Sweden)

    Sarda Kanchan

    2008-01-01

    Full Text Available Abstract Human embryonic stem cells (hESCs have been extensively discussed in public and scientific communities for their potential in treating diseases and injuries. However, not much has been achieved in turning them into safe therapeutic agents. The hurdles in transforming hESCs to therapies start right with the way these cells are derived and maintained in the laboratory, and goes up-to clinical complications related to need for patient specific cell lines, gender specific aspects, age of the cells, and several post transplantation uncertainties. The different types of cells derived through directed differentiation of hESC and used successfully in animal disease and injury models are described briefly. This review gives a brief outlook on the present and the future of hESC based therapies, and talks about the technological advances required for a safe transition from laboratory to clinic.

  5. A quantitative electron microscopic analysis of the keratinizing epithelium of noral human hard palate.

    Science.gov (United States)

    Meyer, M; Schroeder, H E

    1975-01-01

    The epithelium of normal human hard palate was subjected to sterologic analysis. Ten biosies were selected from a total of twenty specimens collected from 9 to 16 year old females, and processed for light- and electron microscopy. At two levels of magnification, electron micrographs were sampled from three strata (basale, spinosum, granulosum) in two locations (epithelial ridges and portions over connective tissue papillae). Stereologic point counting procedures were employed to analyse a total 1560 electron micrographs. In general, the thickness of the palate epithelium was 0.12 mm (over papillae) and 0.31 mm (in ridges), the epithelium is distinctly stratified, and homogeneously ortho-keratinized. From basal to granular layers, the composition of strata revealed decreasing densities of nuclei, mitochondria, membrane-bound organelles and aggregates of free ribosomes. Keratohyalin bodies and membrane coating granules increased, and cytoplasmic filaments with a constant diameter of about 85 A increased from 14 to 30% of cytoplasmic unit volume. The cytoplasmic ground substance occupied a stable 50% of the epithelial cytoplasm in all strata. The composition of basal layers in ridges differed from that over connective tissue papillae. The data are discussed in relation to the observations that (1) an increasing gradient of filament density is not the most characteristic feature of ortho-keratinizing oral epithelium and (2) differences in the degree of differentiation in cells of the stratum basale coincided with the comparable frequency distribution pattern of dividing cells.

  6. Transmission electron microscopic examination of phosphoric acid fuel cell components

    Science.gov (United States)

    Pebler, A.

    1986-01-01

    Transmission electron microscopy (TEM) was used to physically characterize tested and untested phosphoric acid fuel cell (PAFC) components. Those examined included carbon-supported platinum catalysts, carbon backing paper, and Teflon-bonded catalyst layers at various stages of fabrication and after testing in pressurized PAFC's. Applicability of electron diffraction and electron energy loss spectroscopy for identifying the various phases was explored. The discussion focuses on the morphology and size distribution of platinum, the morphology and structural aspects of Teflon in catalyst layers, and the structural evidence of carbon corrosion. Reference is made to other physical characterization techniques where appropriate. A qualitative model of the catalyst layer that emerged from the TEM studies is presented.

  7. Preliminary study on Herpes simplex virus type 1 infection of human oral epithelial cell in vitro

    Institute of Scientific and Technical Information of China (English)

    Jie Zhao; Weibin Sun; Juan Wang

    2008-01-01

    Objective: To explore the functions and mechanisms of herpes simplex virus type 1(HSV-1) while infecting human oral epithelial cells in vitro(being similar to the infection in vivo). Methods:An abundance of HSV-1 strains amplified in Vero cells were used to infect human oral epithelial cells. The culture supernatant was collected to infect Veto cells again. Morphology of HSV-1 was identified by inverted microscope and transmission electron microscope. Nucleic acid of the virus was detected by PCR. Results:The infected human oral epithelial cells didn't display an obvious cytopathic effect(CPE) under inverted microscope(while Veto cells which were infected by the culture supematant showed typical(CPE). The virus particles were not observed in the cytoplasm nor in nucleus of human oral epithelial cells, however under transmission electron microscope in the cytoplasm of Vero cells, the nucleic acid of HSV-1 could be detected in infected human oral epithelial cells, by PCR. Conclusion:HSV-1 can successfully infect human oral epithelial cells. This model may provide a useful approach for studying the pathogenesis of herpes virus-associated periodontal disease.

  8. Electron Microscopy of Staphylococcus aureus Cell Wall Lysis

    Science.gov (United States)

    Virgilio, R.; González, C.; Muñoz, Nubia; Mendoza, Silvia

    1966-01-01

    Virgilio, Rafael (Escuela de Química y Farmacia, Universidad de Chile, Santiago, Chile), C. González, Nubia Muñoz, and Silvia Mendoza. Electron microscopy of Staphylococcus aureus cell wall lysis. J. Bacteriol. 91:2018–2024. 1966.—A crude suspension of Staphylococcus aureus cell walls (strain Cowan III) in buffer solution was shown by electron microscopy to lyse slightly after 16 hr, probably owing to the action of autolysin. The lysis was considerably faster and more intense after the addition of lysozyme. A remarkable reduction in thickness and rigidity of the cell walls, together with the appearance of many irregular protrusions in their outlines, was observed after 2 hr; after 16 hr, there remained only a few recognizable cell wall fragments but many residual particulate remnants. When autolysin was previously inactivated by trypsin, there was a complete inhibition of the lytic action of lysozyme; on the other hand, when autolysin was inactivated by heat and lysozyme was added, a distinct decrease in the thickness of the cell walls was observed, but there was no destruction of the walls. The lytic action of lysozyme, after treatment with hot 5% trichloroacetic acid, gave rise to a marked dissolution of the structure of the cell walls, which became lost against the background, without, however, showing ostensible alteration of wall outlines. From a morphological point of view, the lytic action of autolysin plus lysozyme was quite different from that of trichloroacetic acid plus lysozyme, as shown by electron micrographs, but in both cases it was very intense. This would suggest different mechanisms of action for these agents. Images PMID:5939482

  9. Stem cell factor and c-Kit in human primordial germ cells and fetal ovaries

    DEFF Research Database (Denmark)

    Høyer, Poul Erik; Byskov, Anne Grete; Møllgård, Kjeld

    2005-01-01

    Prenatal ovary (human), Primordial germ cells, Folliculogenesis, c-Kit, Stem cell factor, immunohistochemistry......Prenatal ovary (human), Primordial germ cells, Folliculogenesis, c-Kit, Stem cell factor, immunohistochemistry...

  10. Differences in the microrheology of human embryonic stem cells and human induced pluripotent stem cells.

    Science.gov (United States)

    Daniels, Brian R; Hale, Christopher M; Khatau, Shyam B; Kusuma, Sravanti; Dobrowsky, Terrence M; Gerecht, Sharon; Wirtz, Denis

    2010-12-01

    Embryonic and adult fibroblasts can be returned to pluripotency by the expression of reprogramming genes. Multiple lines of evidence suggest that these human induced pluripotent stem (hiPS) cells and human embryonic stem (hES) cells are behaviorally, karyotypically, and morphologically similar. Here we sought to determine whether the physical properties of hiPS cells, including their micromechanical properties, are different from those of hES cells. To this end, we use the method of particle tracking microrheology to compare the viscoelastic properties of the cytoplasm of hES cells, hiPS cells, and the terminally differentiated parental human fibroblasts from which our hiPS cells are derived. Our results indicate that although the cytoplasm of parental fibroblasts is both viscous and elastic, the cytoplasm of hiPS cells does not exhibit any measurable elasticity and is purely viscous over a wide range of timescales. The viscous phenotype of hiPS cells is recapitulated in parental cells with disassembled actin filament network. The cytoplasm of hES cells is predominantly viscous but contains subcellular regions that are also elastic. This study supports the hypothesis that intracellular elasticity correlates with the degree of cellular differentiation and reveals significant differences in the mechanical properties of hiPS cells and hES cells. Because mechanical stimuli have been shown to mediate the precise fate of differentiating stem cells, our results support the concept that stem cell "softness" is a key feature of force-mediated differentiation of stem cells and suggest there may be subtle functional differences between force-mediated differentiation of hiPS cells and hES cells.

  11. A new view into prokaryotic cell biology from electron cryotomography.

    Science.gov (United States)

    Oikonomou, Catherine M; Jensen, Grant J

    2016-04-01

    Electron cryotomography (ECT) enables intact cells to be visualized in 3D in an essentially native state to 'macromolecular' (∼4 nm) resolution, revealing the basic architectures of complete nanomachines and their arrangements in situ. Since its inception, ECT has advanced our understanding of many aspects of prokaryotic cell biology, from morphogenesis to subcellular compartmentalization and from metabolism to complex interspecies interactions. In this Review, we highlight how ECT has provided structural and mechanistic insights into the physiology of bacteria and archaea and discuss prospects for the future.

  12. End-to-End Thiocyanato-Bridged Helical Chain Polymer and Dichlorido-Bridged Copper(II) Complexes with a Hydrazone Ligand: Synthesis, Characterisation by Electron Paramagnetic Resonance and Variable-Temperature Magnetic Studies, and Inhibitory Effects on Human Colorectal Carcinoma Cells.

    Science.gov (United States)

    Das, Kuheli; Datta, Amitabha; Sinha, Chittaranjan; Huang, Jui-Hsien; Garribba, Eugenio; Hsiao, Ching-Sheng; Hsu, Chin-Lin

    2012-04-01

    The reactions of the tridentate hydrazone ligand, N'-[1-(pyridin-2-yl)ethylidene]acetohydrazide (HL), obtained by condensation of 2-acetylpyridine with acetic hyadrazide, with copper nitrate trihydrate in the presence of thiocyanate, or with CuCl2 produce two distinct coordination compounds, namely a one-dimensional helical coordination chain of [CuL(NCS)] n (1) units, and a doubly chlorido-bridged dinuclear complex [Cu2L2Cl2] (2) (where L=CH3C(O)=N-N=CCH3C5H4N). Single-crystal X-ray structural determination studies reveal that in complex 1, a deprotonated hydrazone ligand L(-) coordinates a copper(II) ion that is bridged to two neighbouring metal centres by SCN(-) anions, generating a one-dimensional helical coordination chain. In complex 2, two symmetry-related, adjacent copper(II) coordination entities are doubly chlorido-bridged, producing a dicopper entity with a Cu⋅⋅⋅Cu distance of 3.402 (1) Å. The two coordination compounds have been fully characterised by elemental analysis, spectroscopic techniques including IR, UV-vis and electron paramagnetic resonance, and variable-temperature magnetic studies. The biological effects of 1 and 2 on the viability of human colorectal carcinoma cells (COLO-205 and HT-29) were evaluated using an MTT assay, and the results indicate that these complexes induce a decrease in cell-population growth of human colorectal carcinoma cells with apoptosis.

  13. Electron Microscopy of Living Cells During in Situ Fluorescence Microscopy.

    Science.gov (United States)

    Liv, Nalan; van Oosten Slingeland, Daan S B; Baudoin, Jean-Pierre; Kruit, Pieter; Piston, David W; Hoogenboom, Jacob P

    2016-01-26

    We present an approach toward dynamic nanoimaging: live fluorescence of cells encapsulated in a bionanoreactor is complemented with in situ scanning electron microscopy (SEM) on an integrated microscope. This allows us to take SEM snapshots on-demand, that is, at a specific location in time, at a desired region of interest, guided by the dynamic fluorescence imaging. We show that this approach enables direct visualization, with EM resolution, of the distribution of bioconjugated quantum dots on cellular extensions during uptake and internalization.

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

    Science.gov (United States)

    Togarrati, Padma Priya; Suknuntha, Kran

    2012-06-01

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

  15. Human colostral cells. I. Separation and characterization.

    Science.gov (United States)

    Crago, S S; Prince, S J; Pretlow, T G; McGhee, J R; Mestecky, J

    1979-12-01

    Analyses of the cells present in human colostrum obtained from fifty-four healthy donors during the first four days of lactation revealed that there were 3.3 x 10(6) (range 1.1 x 10(5)--1.2 x 10(7)) cells per ml of colostrum. Based on histochemical examinations, it was found that this population consisted of 30--47% macrophages, 40--60% polymorphonuclear leucocytes, 5.2--8.9% lymphocytes, and 1.3--2.8% colostral corpuscles; epithelial cells were rarely encountered. The identity of various cell types was confirmed by Wright's stain and by a series of histochemical techniques which disclosed the presence of non-specific esterase, peroxidase, and lipids. For further characterization, the different types of cells were separated by various methods, such as Ficoll-Hypaque density centrifugation, isokinetic centrifugation on a linear Ficoll gradient, adherence to glass or plastic, and phagocytosis of carbonyl iron. Immunohistochemical staining with FITC- and/or TRITC-labelled reagents to IgA, IgM, IgG, K- and lambda-chains, secretory component, lactoferrin, and alpha-lactalbumin were applied to unseparated as well as separated colostral cells. Polymorphonuclear leucocytes (staining for peroxidase) as well as macrophages and colostral corpuscles (staining for non-specific esterase) exhibited numerous intracellular vesicles that contained lipids as well as various combinations of milk proteins. Lymphoid cells did not stain with any of these reagents and plasma cells were not detected among the colostral cells. Individual phagocytic cells contained immunoglobulins of the IgA and IgM classes, both K and lambda light chains, secretory component, lactoferrin, and alpha-lactalbumin. The coincidental appearance of these proteins in single, phagocytic cells but not in lymphoid cells indicate that the cells acquired these proteins by ingestion from the environment. Markers commonly used for the identification of B lymphocytes (surface immunoglobulins) and T lymphocytes (receptors

  16. [Quercetin induces the apoptosis of human PC-3 cells].

    Science.gov (United States)

    Zhu, Qing-Yi; Hu, Rui; Liu, Li; Yuan, Lin; Huang, Wei-Zhou; Ma, Long; Gu, Xiao-Jian

    2011-09-01

    To study the effect of quercetin on the apoptosis of human PC-3 cells. Human PC-3 cells were cultured in vitro and then treated with quercetin at the concentrations of 50, 100, 150, 200 and 250 micromol/L. The inhibition rate of quercetin on the PC-3 cells was detected by MTT, the apoptosis of the cells determined by flow cytometry, and the changes of the cellular ultramicrostructure observed by transmission electron microscopy. Quercetin markedly inhibited the proliferation of PC-3 cells in vitro in a time- and dose-dependent manner. Its inhibition rates were (3.01 +/- 1.32)%, (4.84 +/- 1.73)%, (20.35 +/- 1.30)%, (16.78 +/- 1.89)% and (27.25 +/- 4.01)% at 24 hours, and (10.18 +/- 1.16)%, (6.22 +/- 0.04)%, (24.29 +/- 4.19)%, (22.4 +/- 4.26)% and (41.42 +/- 5.43)% at 48 hours in the 50, 100, 150, 200 and 250 micromol/L groups, respectively, with statistical significance at the concentration of > 150 micromol/L (P apoptosis of PC-3 cells was increased with the elevated concentration and prolonged time of Quercetin treatment, (19.10 +/- 0.28)% and (26.55 +/- 0.78)% at 24 hours, and (27.65 +/- 1.06)% and (38.30 +/- 5.96)% at 48 hours in the 150 and 200 micromol/L groups, respectively (P Quercetin can inhibit the proliferation and induce the apoptosis of human PC-3 cells, but its action mechanism remains to be further investigated.

  17. 21 CFR 864.2280 - Cultured animal and human cells.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Cultured animal and human cells. 864.2280 Section... (CONTINUED) MEDICAL DEVICES HEMATOLOGY AND PATHOLOGY DEVICES Cell And Tissue Culture Products § 864.2280 Cultured animal and human cells. (a) Identification. Cultured animal and human cells are in vitro...

  18. DNA repair responses in human skin cells

    Energy Technology Data Exchange (ETDEWEB)

    Hanawalt, P.C.; Liu, S.C.; Parsons, C.S.

    1981-07-01

    Sunlight and some environmental chemical agents produce lesions in the DNA of human skin cells that if unrepaired may interfere with normal functioning of these cells. The most serious outcome of such interactions may be malignancy. It is therefore important to develop an understanding of mechanisms by which the lesions may be repaired or tolerated without deleterious consequences. Our models for the molecular processing of damaged DNA have been derived largely from the study of bacterial systems. Some similarities but significant differences are revealed when human cell responses are tested against these models. It is also of importance to learn DNA repair responses of epidermal keratinocytes for comparison with the more extensive studies that have been carried out with dermal fibroblasts. Our experimental results thus far indicate similarities for the excision-repair of ultraviolet-induced pyrimidine dimers in human keratinocytes and fibroblasts. Both the monoadducts and the interstrand crosslinks produced in DNA by photoactivated 8-methoxypsoralen (PUVA) can be repaired in normal human fibroblasts but not in those from xeroderma pigmentosum patients. The monoadducts, like pyrimidine dimers, are probably the more mutagenic/carcinogenic lesions while the crosslinks are less easily repaired and probably result in more effective blocking of DNA function. It is suggested that a split-dose protocol that maximizes the production of crosslinks while minimizing the yield of monoadducts may be more effective and potentially less carcinogenic than the single ultraviolet exposure regimen in PUVA therapy for psoriasis.

  19. Electron microscopic visualization of autophagosomes induced by infection of human papillomavirus pseudovirions

    Energy Technology Data Exchange (ETDEWEB)

    Ishii, Yoshiyuki, E-mail: yishii@nih.go.jp

    2013-04-19

    Highlights: •HPV16 pseudovirions (16PsVs) infection induces an autophagy response. •The autophagy was analyzed by transmission electron microscope (TEM). •TEM showed the double-membrane vesicles in HeLa cells inoculated with 16PsVs. •These vesicles incorporated 16PsVs particles in the lumen. •These results imply that autophagosomes are generated from the plasma membrane. -- Abstract: Autophagy is a bulk degradation process for subcellular proteins and organelles to manage cell starvation. Autophagy is associated with the formation of autophagosomes and further functions as a defense mechanism against infection by various pathogens. Human papillomavirus (HPV) infection induces an autophagy response, such as up-regulation of marker proteins for autophagy, in host keratinocytes. However, direct microscopic evidence for autophagy induction by HPV infection is still lacking. Here, I report an electron microscopic analysis of autophagosomes elicited by the entry of HPV pseudovirions (PsVs). HeLa cells showed enhanced infectivity for PsVs of HPV type 16 (16PsVs) when treated with an autophagy inhibitor, suggesting the involvement of autophagy in HPV infection. In HeLa cells inoculated with 16PsVs, transmission electron microscopy showed the presence of cup-shaped, double-membrane vesicles (phagophores) and double-membrane-bound vesicles, which are typical structures of autophagosomes. These double-membrane vesicles displayed a large lumen volume and incorporated 10–50 16PsVs particles in the lumen. These results demonstrate that autophagy is indeed induced during the HPV16 entry process and imply that autophagosomes are generated from the plasma membrane by HPV infection.

  20. Transmission electron microscopy reveals distinct macrophage- and tick cell-specific morphological stages of Ehrlichia chaffeensis.

    Directory of Open Access Journals (Sweden)

    Sarah E Dedonder

    Full Text Available BACKGROUND: Ehrlichia chaffeensis is an emerging tick-borne rickettsial pathogen responsible for human monocytic ehrlichiosis. Despite the induction of an active host immune response, the pathogen has evolved to persist in its vertebrate and tick hosts. Understanding how the organism progresses in tick and vertebrate host cells is critical in identifying effective strategies to block the pathogen transmission. Our recent molecular and proteomic studies revealed differences in numerous expressed proteins of the organism during its growth in different host environments. METHODOLOGY/PRINCIPAL FINDINGS: Transmission electron microscopy analysis was performed to assess morphological changes in the bacterium within macrophages and tick cells. The stages of pathogen progression observed included the attachment of the organism to the host cells, its engulfment and replication within a morulae by binary fission and release of the organisms from infected host cells by complete host cell lysis or by exocytosis. E. chaffeensis grown in tick cells was highly pleomorphic and appears to replicate by both binary fission and filamentous type cell divisions. The presence of Ehrlichia-like inclusions was also observed within the nucleus of both macrophages and tick cells. This observation was confirmed by confocal microscopy and immunoblot analysis. CONCLUSIONS/SIGNIFICANCE: Morphological differences in the pathogen's progression, replication, and processing within macrophages and tick cells provide further evidence that E. chaffeensis employs unique host-cell specific strategies in support of adaptation to vertebrate and tick cell environments.

  1. Human cytomegalovirus induces alteration of β-actin mRNA and microfilaments in human embryo fibroblast cells

    Institute of Scientific and Technical Information of China (English)

    林茂芳; 魏国庆; 黄河; 蔡真

    2004-01-01

    Objective: To investigate the infection of human embryo fibroblast cell line HF cells by CMV as well as the effects of CMV on β-actin mRNA and microfilaments. Methods: HF cells shape was observed after the infection of CMV.RT-PCR assay was used to detect the mRNA expression of CMV immediate early (IE) gene, β-actin and GAPDH genes of HF cells infected by CMV. CMV particles and cell microfilaments were detected with electron microscope. Results: Shape of HF cell changed after the infection by CMV. HF cells infected by CMV could express IE mRNA and the expression of β-actin mRNA decreased in a time-and titer-dependent manner compared with the uninfected HF cells whose expression of GAPDH mRNA did not change much. CMV particles were found with electron microscope in the cells. Microfilaments were ruptured and shortened after the infection of CMV. Conclusion: CMV can not only infect human embryo fibroblast cells line HF cells and replicate in the cells, but can also affect the expression of β-actin mRNA and the microfilaments.

  2. Human T Cell Memory: A Dynamic View

    Directory of Open Access Journals (Sweden)

    Derek C. Macallan

    2017-02-01

    Full Text Available Long-term T cell-mediated protection depends upon the formation of a pool of memory cells to protect against future pathogen challenge. In this review we argue that looking at T cell memory from a dynamic viewpoint can help in understanding how memory populations are maintained following pathogen exposure or vaccination. For example, a dynamic view resolves the apparent paradox between the relatively short lifespans of individual memory cells and very long-lived immunological memory by focussing on the persistence of clonal populations, rather than individual cells. Clonal survival is achieved by balancing proliferation, death and differentiation rates within and between identifiable phenotypic pools; such pools correspond broadly to sequential stages in the linear differentiation pathway. Each pool has its own characteristic kinetics, but only when considered as a population; single cells exhibit considerable heterogeneity. In humans, we tend to concentrate on circulating cells, but memory T cells in non-lymphoid tissues and bone marrow are increasingly recognised as critical for immune defence; their kinetics, however, remain largely unexplored. Considering vaccination from this viewpoint shifts the focus from the size of the primary response to the survival of the clone and enables identification of critical system pinch-points and opportunities to improve vaccine efficacy.

  3. Biological impact of human embryonic stem cells.

    Science.gov (United States)

    Martín, Miguel; Menéndez, Pablo

    2012-01-01

    Research on human embryonic stem cells (hESCs) and induced pluripotent (iPS) stem cells is currently a field of great potential in biomedicine. These cells represent a highly valuable tool for developmental biology studies, disease models, and drug screening and toxicity. The ultimate goal of hESCs and iPS cell research is the treatment of diseases or disorders for which there is currently no treatment or existing therapies are only partially effective. Despite the disproportionate short-term hopes generated, which are putting too much pressure on scientists, the international scientific community is making rapid progress in understanding hESCs and iPS cells. Nonetheless, great efforts have to be made to provide an answer to still quite basic questions concerning their biology. Moreover, translation to clinical applications in cell replacement therapy requires prior solution to ethical barriers. The recent development of iPS cells has provided a strong alternative to overcome ethical issues concerning hESCs. However, an in-depth characterization of their genetic and epigenetic features, as well as their differentiation potential still remains to be undertaken. This chapter will describe, precisely, what the critical issues are, where scientific and ethical barriers stand, and how we are to overcome them. Only then, we shall finally discover whether hESCs and iPS cells will allow building reproducible disease models, and whether they really are a safe tool, with great potential for regenerative medicine.

  4. CIF2Cell: Generating geometries for electronic structure programs

    Science.gov (United States)

    Björkman, Torbjörn

    2011-05-01

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

  5. Human fetal liver stromal cells expressing erythropoietin promote hematopoietic development from human embryonic stem cells.

    Science.gov (United States)

    Yang, Chao; Ji, Lei; Yue, Wen; Shi, Shuang-Shuang; Wang, Ruo-Yong; Li, Yan-Hua; Xie, Xiao-Yan; Xi, Jia-Fei; He, Li-Juan; Nan, Xue; Pei, Xue-Tao

    2012-02-01

    Blood cells transfusion and hematopoietic stem cells (HSCs) transplantation are important methods for cell therapy. They are widely used in the treatment of incurable hematological disorder, infectious diseases, genetic diseases, and immunologic deficiency. However, their availability is limited by quantity, capacity of proliferation and the risk of blood transfusion complications. Recently, human embryonic stem cells (hESCs) have been shown to be an alternative resource for the generation of hematopoietic cells. In the current study, we describe a novel method for the efficient production of hematopoietic cells from hESCs. The stable human fetal liver stromal cell lines (hFLSCs) expressing erythropoietin (EPO) were established using the lentiviral system. We observed that the supernatant from the EPO transfected hFLSCs could induce the hESCs differentiation into hematopoietic cells, especially erythroid cells. They not only expressed fetal and embryonic globins but also expressed the adult-globin chain on further maturation. In addition, these hESCs-derived erythroid cells possess oxygen-transporting capacity, which indicated hESCs could generate terminally mature progenies. This should be useful for ultimately developing an animal-free culture system to generate large numbers of erythroid cells from hESCs and provide an experimental model to study early human erythropoiesis.

  6. Entry of Oncolytic Herpes Simplex Virus into Human Squamous Cell Carcinoma Cells by Ultrasound

    Directory of Open Access Journals (Sweden)

    Shusuke Okunaga

    2015-10-01

    Full Text Available Low-intensity ultrasound is a useful method to introduce materials into cells due to the transient formation of micropores, called sonoporations, on the cell membrane. Whether oncolytic herpes simplex virus type 1 (HSV-1 can be introduced into oral squamous cell carcinoma (SCC cells through membrane pores remains undetermined. Human SCC cell line SAS and oncolytic HSV-1 RH2, which was deficient in the 134.5 gene and fusogenic, were used. Cells were exposed to ultrasound in the presence or absence of microbubbles. The increase of virus entry was estimated by plaque numbers. Viral infection was hardly established without the adsorption step, but plaque number was increased by the exposure of HSV-1-inoculated cells to ultrasound. Plaque number was also increased even if SAS cells were exposed to ultrasound and inoculated with RH2 without the adsorption step. This effect was abolished when the interval from ultrasound exposure to virus inoculation was prolonged. Scanning electron microscopy revealed depressed spots on the cell surface after exposure to ultrasound. These results suggest that oncolytic HSV-1 RH2 can be introduced into SAS cells through ultrasound-mediated pores of the cell membrane that are resealed after an interval.

  7. Morphologic characteristics of processes of nucleus pulposus cells in adult human intervertebral disc

    Science.gov (United States)

    Liu, Xiaoyun; Wu, Xinghuo; Hui, Liu; Xu, Weihua; Liu, Xianze; Yang, Shuhua

    2008-12-01

    To explore morphologic characterizatics of cellular processes from adult human nucleus pulposus cells, the nucleus pulposus of adult human intervertebral disc were obtained from 8 patients (Thompson's grade I~II) and then the tissues specimens were carried out by frozen section and electron microscopic section as well as cell isolation and cultured, processes of nucleus pulposus cells were examined using light microscopy, laser scanning confocal microscopy and transmission electron microscopy. When examined at both the confocal and electron microscope level, all the cells possessed the processes and adjacent nucleus pulposus cells processes possessed a gap junction. But elongated and round cells can be examined when NP cells were monolayer cultured. The rate of elongated cells to round cells is 2.3 to 1. The elongated cells protrude along with the long axis of cell body without second processes. Dendritic processes of round cells protrude to all directions from the cell body with multiple-level processes. Processes are one of the morphologic characteristics of intervertebral disc cells which are different from articular cartilage chondrocytes. The research on processes functions will be helpful to understand pathomechanism of intervertebral disc degradation and open a new approach for cytobiology treatment of the intervertebral disc diseases.

  8. Cell phoney: human cloning after Quintavalle.

    Science.gov (United States)

    Morgan, Derek; Ford, Mary

    2004-12-01

    Reproductive cloning has thrown up new scientific possibilities, ethical conundrums, and legal challenges. An initial question, considered by the English courts in 2003, was whether the technique presently available, that of cell nucleus replacement, falls outside the provisions of the Human Fertilisation and Embryology Act 1990. If it does, the creation and use, including use in research protocols, of human embryos would be unregulated, disclosing a need to consider remedial legislation. The resolution by the courts of this legal question dramatically engages them in a resolution of fundamental ethical dilemmas, and discloses the possibilities and limitation of negotiating science policy through the processes of litigation.

  9. Light and electron microscopic study of the medial collateral ligament epiligament tissue in human knees.

    Science.gov (United States)

    Georgiev, Georgi P; Iliev, Alexandar; Kotov, Georgi; Kinov, Plamen; Slavchev, Svetoslav; Landzhov, Boycho

    2017-05-18

    To examine the normal morphology of the epiligament tissue of the knee medial collateral ligament (MCL) in humans. Several samples of the mid-substance of the MCL of the knee joint from 7 fresh human cadavers (3 females and 4 males) were taken. Examination of the epiligament tissue was conducted by light microscopy and photomicrography on semi-thin sections of formalin fixed paraffin-embedded blocks that were routinely stained with haematoxylin and eosin, Mallory stain and Van Gieson's stain. Electron microscopy of the epiligament tissue was performed on ultra-thin sections incubated in 1% osmium tetroxide and contrasted with 2.5% uranyl acetate, lead nitrate, and sodium citrate. The current light microscopic study demonstrated that the epiligament of the MCL consisted of fibroblasts, fibrocytes, adipocytes, neuro-vascular bundles and numerous multidirectional collagen fibers. In contrast, the ligament body was poorly vascularised, composed of hypo-cellular fascicles which were formed of longitudinal groups of collagen fibers. Moreover, most of the vessels of the epiligament-ligament complex were situated in the epiligament tissue. The electron microscopic study revealed fibroblasts with various shapes in the epiligament substance. All of them had the ultrastructural characteristics of active cells with large nuclei, well developed rough endoplasmic reticulum, multiple ribosomes, poorly developed Golgi apparatus, elliptical mitochondria and oval lysosomes. The electron microscopy also confirmed the presence of adipocytes, mast cells, myelinated and unmyelinated nerve fibers and chaotically oriented collagen fibers. Significant differences exist between the normal structure of the ligament and the epiligament whose morphology and function is to be studied further.

  10. Lymphoid Cell-Glioma Cell Interaction Enhances Cell Coat Production by Human Gliomas: Novel Suppressor Mechanism

    Science.gov (United States)

    Dick, Steven J.; Macchi, Beatrice; Papazoglou, Savvas; Oldfield, Edward H.; Kornblith, Paul L.; Smith, Barry H.; Gately, Maurice K.

    1983-05-01

    Certain human glioma lines produce mucopolysaccharide coats that impair the generation of cytolytic lymphocytes in response to these lines in vitro. Coat production is substantially enhanced by the interaction of glioma cells with a macromolecular factor released by human peripheral blood mononuclear cells in culture. This interaction thus constitutes an unusual mechanism by which inflammatory cells may nonspecifically suppress the cellular immune response to at least one class of solid tumors in humans.

  11. Human induced pluripotent stem cell-derived models to investigate human cytomegalovirus infection in neural cells.

    Directory of Open Access Journals (Sweden)

    Leonardo D'Aiuto

    Full Text Available Human cytomegalovirus (HCMV infection is one of the leading prenatal causes of congenital mental retardation and deformities world-wide. Access to cultured human neuronal lineages, necessary to understand the species specific pathogenic effects of HCMV, has been limited by difficulties in sustaining primary human neuronal cultures. Human induced pluripotent stem (iPS cells now provide an opportunity for such research. We derived iPS cells from human adult fibroblasts and induced neural lineages to investigate their susceptibility to infection with HCMV strain Ad169. Analysis of iPS cells, iPS-derived neural stem cells (NSCs, neural progenitor cells (NPCs and neurons suggests that (i iPS cells are not permissive to HCMV infection, i.e., they do not permit a full viral replication cycle; (ii Neural stem cells have impaired differentiation when infected by HCMV; (iii NPCs are fully permissive for HCMV infection; altered expression of genes related to neural metabolism or neuronal differentiation is also observed; (iv most iPS-derived neurons are not permissive to HCMV infection; and (v infected neurons have impaired calcium influx in response to glutamate.

  12. Human somatic cell nuclear transfer and cloning.

    Science.gov (United States)

    2012-10-01

    This document presents arguments that conclude that it is unethical to use somatic cell nuclear transfer (SCNT) for infertility treatment due to concerns about safety; the unknown impact of SCNT on children, families, and society; and the availability of other ethically acceptable means of assisted reproduction. This document replaces the ASRM Ethics Committee report titled, "Human somatic cell nuclear transfer (cloning)," last published in Fertil Steril 2000;74:873-6. Copyright © 2012 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  13. What do we know about the structure of human thymic Hassall's corpuscles? A histochemical, immunohistochemical, and electron microscopic study.

    Science.gov (United States)

    Mikušová, Renáta; Mešťanová, Veronika; Polák, Štefan; Varga, Ivan

    2017-05-01

    Hassall's corpuscles are the most prominent structures in the human thymus. However, relatively few analyses have been performed to determine their function and cellular origins during development. In this study, we evaluated the cellular microenvironment of human thymic Hassall's corpuscles using histochemistry, immunohistochemistry, and transmission electron microscopy. We examined 95 human thymic tissue samples, which were perioperatively obtained from children undergoing cardiac surgery. To characterize the complex cellular microenvironment of human thymic corpuscles, we used a panel of 14 different antibodies to identify discrete cell types. We also utilized various histochemical methods (PAS reaction, alcian blue staining, alkaline phosphatase and acid phosphatase activity staining, von Kossa staining of calcified particles) and transmission electron microscopy to visualize these structures. Considerable variation in the sizes, shapes, and numbers of Hassall's corpuscles was observed, even amongst children of the same age. Inside the largest Hassall's corpuscles, cystic dilatation with an accumulation of cellular debris was found. These morphological observations might be associated with disruptions in the formation, migration, or differentiation of cardiac neural crest cells, which are essential for heart and thymus development. Immunohistochemical staining and electron microscopy revealed that Hassall's corpuscles resemble other types of stratified squamous epithelia. Most Hassall's corpuscles are heterocellular, consisting of thymic epithelial cells, macrophages, interdigitating dendritic cells, myoid cells, and, occasionally, mast cells and lymphocytes. To explore the potential functions of Hassall's corpuscles, we found that the concentrations of B-lymphocytes and BCL2-positive lymphocytes suggested a role in regulation of lymphopoiesis. We also found that these structures do not originate from the perivascular epithelium as previously proposed, nor

  14. Sequestration of human cytomegalovirus by human renal and mammary epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Twite, Nicolas [Institute for Medical Immunology, Université Libre de Bruxelles, Rue A. Bolland 8, B-6041 Charleroi (Belgium); Andrei, Graciela [Laboratory of Virology and Chemotherapy, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven (Belgium); Kummert, Caroline [ImmuneHealth, Rue A. Bolland 8, B-6041 Charleroi (Belgium); Donner, Catherine [Department of Obstetrics and Gynecology, Erasme Hospital, Route de Lennik 808, 1070 Brussels (Belgium); Perez-Morga, David [Laboratory of Molecular Parasitology, Institut de Biologie et Médecine Moléculaires, Université Libre de Bruxelles, Gosselies (Belgium); De Vos, Rita [Pathology Department, U.Z. Leuven, Minderbroedersstraat 12, Leuven (Belgium); Snoeck, Robert, E-mail: Robert.Snoeck@Rega.kuleuven.be [Laboratory of Virology and Chemotherapy, Department of Microbiology and Immunology, Rega Institute for Medical Research, KU Leuven (Belgium); Marchant, Arnaud, E-mail: arnaud.marchant@ulb.ac.be [Institute for Medical Immunology, Université Libre de Bruxelles, Rue A. Bolland 8, B-6041 Charleroi (Belgium); ImmuneHealth, Rue A. Bolland 8, B-6041 Charleroi (Belgium)

    2014-07-15

    Urine and breast milk represent the main routes of human cytomegalovirus (HCMV) transmission but the contribution of renal and mammary epithelial cells to viral excretion remains unclear. We observed that kidney and mammary epithelial cells were permissive to HCMV infection and expressed immediate early, early and late antigens within 72 h of infection. During the first 24 h after infection, high titers of infectious virus were measured associated to the cells and in culture supernatants, independently of de novo synthesis of virus progeny. This phenomenon was not observed in HCMV-infected fibroblasts and suggested the sequestration and the release of HCMV by epithelial cells. This hypothesis was supported by confocal and electron microscopy analyses. The sequestration and progressive release of HCMV by kidney and mammary epithelial cells may play an important role in the excretion of the virus in urine and breast milk and may thereby contribute to HCMV transmission. - Highlights: • Primary renal and mammary epithelial cells are permissive to HCMV infection. • HCMV is sequestered by epithelial cells and this phenomenon does not require viral replication. • HCMV sequestration by epithelial cells is reduced by antibodies and IFN-γ.

  15. TALEN-Induced Translocations in Human Cells.

    Science.gov (United States)

    Piganeau, Marion; Renouf, Benjamin; Ghezraoui, Hind; Brunet, Erika

    2016-01-01

    Induction of chromosomal translocations in human cells is of a great interest to study tumorigenesis and genome instability. Here, we explain in detail a method to induce translocations using the transcription activator-like effector nucleases (TALENs). We describe how to detect translocation formation by PCR, calculate translocation frequency by 96-well PCR screen, and analyze breakpoint junctions. When inducing cancer translocations, it is also possible to detect the fusion gene by FISH analysis or western blot.

  16. The core regulatory network in human cells.

    Science.gov (United States)

    Kim, Man-Sun; Kim, Dongsan; Kang, Nam Sook; Kim, Jeong-Rae

    2017-03-04

    In order to discover the common characteristics of various cell types in the human body, many researches have been conducted to find the set of genes commonly expressed in various cell types and tissues. However, the functional characteristics of a cell is determined by the complex regulatory relationships among the genes rather than by expressed genes themselves. Therefore, it is more important to identify and analyze a core regulatory network where all regulatory relationship between genes are active across all cell types to uncover the common features of various cell types. Here, based on hundreds of tissue-specific gene regulatory networks constructed by recent genome-wide experimental data, we constructed the core regulatory network. Interestingly, we found that the core regulatory network is organized by simple cascade and has few complex regulations such as feedback or feed-forward loops. Moreover, we discovered that the regulatory links from genes in the core regulatory network to genes in the peripheral regulatory network are much more abundant than the reverse direction links. These results suggest that the core regulatory network locates at the top of regulatory network and plays a role as a 'hub' in terms of information flow, and the information that is common to all cells can be modified to achieve the tissue-specific characteristics through various types of feedback and feed-forward loops in the peripheral regulatory networks. We also found that the genes in the core regulatory network are evolutionary conserved, essential and non-disease, non-druggable genes compared to the peripheral genes. Overall, our study provides an insight into how all human cells share a common function and generate tissue-specific functional traits by transmitting and processing information through regulatory network.

  17. Resveratrol Induces Apoptosis in Human Osteosarcoma MG63 Cells

    Institute of Scientific and Technical Information of China (English)

    Yan Liu; Xin Wang; Yuxin Xie; Jingui Zhang; Qingshan Wang; Xianhui Xu

    2008-01-01

    OBJECTIVE To investigate apoptosis in human osteosarcoma MG63 cells induced by resveratrol and the molecular mechanism involved.METHODS MG63 cells were treated with different concentrations of resveratrol and transmission electron microscopy was used to observe morphological changes occurring in apoptosis.The MTT method was used to determine the inhibitory rate and flow cytometry was used to assess apoptosis and to analyze the expression of the p21ciP1/WAF1 and survivin proteins;the expression of p21ciP1/WAF1 and survivin mRNAs was analyzed by the reverse transcriptase polymerase chain reaction (RT-PCR).RESULTS After resveratrol treatment,the growth of the MG63 cells was significantly inhibited in a time- and dose-dependent fashion.By transmission electron microscopy,the cells displayed morphological changes characteristic of apoptosis,including formation of cytoplasmic vacuoles,chromatin condensation and margination.Flow cytometry showed that the growth of the cells was inhibited after resveratrol (10 mg/L and 20 mg/L) treatment.The inhibitory rates were (11.9 ±0.63)% and (19.7 ± 0.88)%respectively.The quantity of treated cells in G0/G1 transition was increased,but the number in the S phase and G2/M transition was decreased.A subdiploid peak was observed.The expression of p21ciP1/WAF1 was up-regulated while survivin was down-regulated.CONCLUSION Resveratrol can inhibit growth and induce apoptosis of MG63 cells.Its molecular mechanism might be related to modulation of survivin and p21ciP1/WAF1 expression.

  18. Cell Culture Assay for Human Noroviruses [response

    Energy Technology Data Exchange (ETDEWEB)

    Straub, Tim M.; Honer Zu Bentrup, Kerstin; Orosz Coghlan, Patricia; Dohnalkova, Alice; Mayer, Brooke K.; Bartholomew, Rachel A.; Valdez, Catherine O.; Bruckner-Lea, Cindy J.; Gerba, Charles P.; Abbaszadegan, Morteza A.; Nickerson, Cheryl A.

    2007-07-01

    We appreciate the comments provided by Leung et al., in response to our recently published article “In Vitro Cell Culture Infectivity Assay for Human Noroviruses” by Straub et al. (1). The specific aim of our project was to develop an in vitro cell culture infectivity assay for human noroviruses (hNoV) to enhance risk assessments when they are detected in water supplies. Reverse transcription (RT) qualitative or quantitative PCR are the primary assays for waterborne NoV monitoring. However, these assays cannot distinguish between infectious vs. non-infectious virions. When hNoV is detected in water supplies, information provided by our infectivity assay will significantly improve risk assessment models and protect human health, regardless of whether we are propagating NoV. Indeed, in vitro cell culture infectivity assays for the waterborne pathogen Cryptosporidium parvum that supplement approved fluorescent microscopy assays, do not result in amplification of the environmentally resistant hard-walled oocysts (2). However, identification of life cycle stages in cell culture provides evidence of infectious oocysts in a water supply. Nonetheless, Leung et al.’s assertion regarding the suitability of our method for the in vitro propagation of high titers of NoV is valid for the medical research community. In this case, well-characterized challenge pools of virus would be useful for developing and testing diagnostics, therapeutics, and vaccines. As further validation of our published findings, we have now optimized RT quantitative PCR to assess the level of viral production in cell culture, where we are indeed finding significant increases in viral titer. The magnitude and time course of these increases is dependent on both virus strain and multiplicity of infection. We are currently preparing a manuscript that will discuss these findings in greater detail, and the implications this may have for creating viral challenge pools

  19. Convergent Flows: Humanities Scholars and Their Interactions with Electronic Texts

    Science.gov (United States)

    Sukovic, Suzana

    2008-01-01

    This article reports research findings related to converging formats, media, practices, and ideas in the process of academics' interaction with electronic texts during a research project. The findings are part of the results of a study that explored interactions of scholars in literary and historical studies with electronic texts as primary…

  20. Preliminary study on human fibroblasts as feeder layer for human embryonic stem cells culture in vitro

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    To avoid the direct contact with mouse cells and possible heterogeneous pathogen in future application, we need to replace mouse embryonic fibroblastswith human fibroblasts as the feeder layer to maintain human embryonic stem cells growth in the undifferentiated state. We successfully use human fibroblasts derived from aborted fetus and adult prepuce as feeder layer to maintain human embryonic stem cells growth. During the passage and growth on this feeder layer, the human embryonic stem cells can keep their undifferentiated state.

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

    Science.gov (United States)

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

    2012-09-01

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

  2. Human umbilical cord Wharton's Jelly-derived mesenchymal stem cells differentiation into nerve-like cells

    Institute of Scientific and Technical Information of China (English)

    MA Lian; FENG Xue-yong; CUI Bing-lin; Frieda Law; JIANG Xue-wu; YANG Li-ye; XIE Qing-dong; HUANG Tian-hua

    2005-01-01

    Background The two most basic properties of mesenchymal stem cells (MSCs) are the capacities to self-renew indefinitely and differentiate into multiple cells and tissue types. The cells from human umbilical cord Wharton's Jelly have properties of MSCs and represent a rich source of primitive cells. This study was conducted to explore the possibility of inducing human umbilical cord Wharton's Jelly-derived MSCs to differentiate into nerve-like cells.Methods MSCs were cultured from the Wharton's Jelly taken from human umbilical cord of babies delivered after full-term normal labor. Salvia miltiorrhiza and β-mercaptoethanol were used to induce the human umbilical cord-derived MSCs to differentiate. The expression of neural protein markers was shown by immunocytochemistry. The induction process was monitored by phase contrast microscopy, electron microscopy (EM), and laser scanning confocal microscopy (LSCM) .The pleiotrophin and nestin genes were measured by reverse transcription-polymerase chain reaction (RT-PCR). Results MSCs in the Wharton's Jelly were easily attainable and could be maintained and expanded in culture. They were positive for markers of MSCs, but negative for markers of hematopoietic cells and graft-versus-host disease (GVHD)-related cells. Treatment with Salvia miltiorrhiza caused Wharton's Jelly cells to undergo profound morphological changes. The induced MSCs developed rounded cell bodies with multiple neurite-like extensions. Eventually they developed processes that formed networks reminiscent of primary cultures of neurons. Salvia miltiorrhiza and β-mercaptoethanol also induced MSCs to express nestin, β-tubulinⅢ, neurofilament (NF) and glial fibrillary acidic protein (GFAP). It was confirmed by RT-PCR that MSCs could express pleiotrophin both before and after induction by Salvia miltiorrhiza. The expression was markedly enhanced after induction and the nestin gene was also expressed.Conclusions MSCs could be isolated from human umbilical

  3. Primitive cardiac cells from human embryonic stem cells.

    Science.gov (United States)

    Hudson, James; Titmarsh, Drew; Hidalgo, Alejandro; Wolvetang, Ernst; Cooper-White, Justin

    2012-06-10

    Pluripotent stem cell-derived cardiomyocytes are currently being investigated for in vitro human heart models and as potential therapeutics for heart failure. In this study, we have developed a differentiation protocol that minimizes the need for specific human embryonic stem cell (hESC) line optimization. We first reduced the heterogeneity that exists within the starting population of bulk cultured hESCs by using cells adapted to single-cell passaging in a 2-dimensional (2D) culture format. Compared with bulk cultures, single-cell cultures comprised larger fractions of TG30(hi)/OCT4(hi) cells, corresponding to an increased expression of pluripotency markers OCT4 and NANOG, and reduced expression of early lineage-specific markers. A 2D temporal differentiation protocol was then developed, aimed at reducing the inherent heterogeneity and variability of embryoid body-based protocols, with induction of primitive streak cells using bone morphogenetic protein 4 and activin A, followed by cardiogenesis via inhibition of Wnt signaling using the small molecules IWP-4 or IWR-1. IWP-4 treatment resulted in a large percentage of cells expressing low amounts of cardiac myosin heavy chain and expression of early cardiac progenitor markers ISL1 and NKX2-5, thus indicating the production of large numbers of immature cardiomyocytes (~65,000/cm(2) or ~1.5 per input hESC). This protocol was shown to be effective in HES3, H9, and, to a lesser, extent, MEL1 hESC lines. In addition, we observed that IWR-1 induced predominantly atrial myosin light chain (MLC2a) expression, whereas IWP-4 induced expression of both atrial (MLC2a) and ventricular (MLC2v) forms. The intrinsic flexibility and scalability of this 2D protocol mean that the output population of primitive cardiomyocytes will be particularly accessible and useful for the investigation of molecular mechanisms driving terminal cardiomyocyte differentiation, and potentially for the future treatment of heart failure.

  4. Apoptosis of Human Trabecular Meshwork Cells Induced by Transforming Growth Factor-p2 in vitro

    Institute of Scientific and Technical Information of China (English)

    CAO Yang(曹 阳); WEI Houren(魏厚仁); Pfaffl Michael; DA Banghong(笪邦红); LI Zhongyu(李忠玉)

    2004-01-01

    Summary: Whether transforming growth factor-β2 (TGF-β2) induces apoptosis of human trabecular meshwork cells was investigated in vitro. Cultured 3-5 passage human trabecular meshwork cells were treated with 0 (control), 0.32, 1, 3.2 ng/ml TGF-β2 for 48 h and divided into control group and experimental group. The apoptosis of human trabecular meshwork cells was examined by transmisson electron microscopy, TUNEL technique and flow cytometry. The results showed characteristic morphologic changes of apoptotic cells were observed under transmission electron microscopy.DNA fragmentation of human trabecular meshwork cells was found by TUNEL technique. Quantitative analysis of flow cytometry showed that percentages of apoptotic human trabecular meshwork cells were (2.79±0.44) %, (4.43±1.17) % and (9. 60±2.05) % respectively with different concentrations [1 ng/ml (P<0. 05), 3.2 ng/ml (P<0.01)] of TGF-β2 with the difference being significant between experimental group and control group[(1. 41±0.34) %]. It was concluded that TGF-β2 can induce apoptosis of human trabecular meshwork cells in vitro and may be involved in the decrease of trabecular meshwork cells in the patients with primary open angle glaucoma and aging of normal people.

  5. Appearance of Human Plasma Cells Following Differentiation of Human B Cells in NOD/SCID Mouse Spleen

    OpenAIRE

    2003-01-01

    Relatively little is known for the differentiation and maturation process of human B cells to plasma cells. This is particularly important in reconstitution work involving transfer of autoantibodies. To address this issue, we transplanted human peripheral blood mononuclear cells (PBMC) directly into the spleen of irradiated NOD/SCID mice depleted of natural killer cell activity. Within 6 weeks, naïve B cells differentiated into memory B cells and, importantly, the numbers of human CD138+ plas...

  6. Establishment of Human Neural Progenitor Cells from Human Induced Pluripotent Stem Cells with Diverse Tissue Origins

    Directory of Open Access Journals (Sweden)

    Hayato Fukusumi

    2016-01-01

    Full Text Available Human neural progenitor cells (hNPCs have previously been generated from limited numbers of human induced pluripotent stem cell (hiPSC clones. Here, 21 hiPSC clones derived from human dermal fibroblasts, cord blood cells, and peripheral blood mononuclear cells were differentiated using two neural induction methods, an embryoid body (EB formation-based method and an EB formation method using dual SMAD inhibitors (dSMADi. Our results showed that expandable hNPCs could be generated from hiPSC clones with diverse somatic tissue origins. The established hNPCs exhibited a mid/hindbrain-type neural identity and uniform expression of neural progenitor genes.

  7. Human microglial cells synthesize albumin in brain.

    Directory of Open Access Journals (Sweden)

    Sung-Min Ahn

    Full Text Available Albumin, an abundant plasma protein with multifunctional properties, is mainly synthesized in the liver. Albumin has been implicated in Alzheimer's disease (AD since it can bind to and transport amyloid beta (Abeta, the causative agent of AD; albumin is also a potent inhibitor of Abeta polymerization. Despite evidence of non-hepatic transcription of albumin in many tissues including kidney and pancreas, non-hepatic synthesis of albumin at the protein level has been rarely confirmed. In a pilot phase study of Human Brain Proteome Project, we found evidence that microglial cells in brain may synthesize albumin. Here we report, for the first time, the de novo synthesis of albumin in human microglial cells in brain. Furthermore, we demonstrate that the synthesis and secretion of albumin from microglial cells is enhanced upon microglial activation by Abeta(1-42- or lipopolysaccharide (LPS-treatment. These data indicate that microglial cells may play a beneficial role in AD by secreting albumin that not only inhibits Abeta polymerization but also increases its clearance.

  8. Neocortical glial cell numbers in human brains

    DEFF Research Database (Denmark)

    Pelvig, D.P.; Pakkenberg, H.; Stark, A.K.

    2008-01-01

    and neurons and counting were done in each of the four lobes. The study showed that the different subpopulations of glial cells behave differently as a function of age; the number of oligodendrocytes showed a significant 27% decrease over adult life and a strong correlation to the total number of neurons...... while the total astrocyte number is constant through life; finally males have a 28% higher number of neocortical glial cells and a 19% higher neocortical neuron number than females. The overall total number of neocortical neurons and glial cells was 49.3 billion in females and 65.2 billion in males......, a difference of 24% with a high biological variance. These numbers can serve as reference values in quantitative studies of the human neocortex. (C) 2007 Elsevier Inc. All rights reserved Udgivelsesdato: 2008/11...

  9. Characterizing motility dynamics in human RPE cells

    Science.gov (United States)

    Liu, Zhuolin; Kurokawa, Kazuhiro; Zhang, Furu; Miller, Donald T.

    2017-02-01

    Retinal pigment epithelium (RPE) cells are vital to health of the outer retina, however, are often compromised in ageing and ocular diseases that lead to blindness. Early manifestation of RPE disruption occurs at the cellular level, but while in vivo biomarkers at this scale hold considerable promise, RPE cells have proven extremely challenging to image in the living human eye. Recently we addressed this problem by using organelle motility as a novel contrast agent to enhance the RPE cell in conjunction with 3D resolution of adaptive optics-optical coherence tomography (AO-OCT) to section the RPE layer. In this study, we expand on the central novelty of our method - organelle motility - by characterizing the dynamics of the motility in individual RPE cells, important because of its direct link to RPE physiology. To do this, AO-OCT videos of the same retinal patch were acquired at approximately 1 min intervals or less, time stamped, and registered in 3D with sub-cellular accuracy. Motility was quantified by an exponential decay time constant, the time for motility to decorrelate the speckle field across an RPE cell. In two normal subjects, we found the decay time constant to be just 3 seconds, thus indicating rapid motility in normal RPE cells.

  10. Human cell culture in a space bioreactor

    Science.gov (United States)

    Morrison, Dennis R.

    1988-01-01

    Microgravity offers new ways of handling fluids, gases, and growing mammalian cells in efficient suspension cultures. In 1976 bioreactor engineers designed a system using a cylindrical reactor vessel in which the cells and medium are slowly mixed. The reaction chamber is interchangeable and can be used for several types of cell cultures. NASA has methodically developed unique suspension type cell and recovery apparatus culture systems for bioprocess technology experiments and production of biological products in microgravity. The first Space Bioreactor was designed for microprocessor control, no gaseous headspace, circulation and resupply of culture medium, and slow mixing in very low shear regimes. Various ground based bioreactors are being used to test reactor vessel design, on-line sensors, effects of shear, nutrient supply, and waste removal from continuous culture of human cells attached to microcarriers. The small Bioreactor is being constructed for flight experiments in the Shuttle Middeck to verify systems operation under microgravity conditions and to measure the efficiencies of mass transport, gas transfer, oxygen consumption and control of low shear stress on cells.

  11. Crystalline structures in human pancreatic beta cell adenoma.

    Science.gov (United States)

    Mori, H; Kawai, T; Tanaka, T; Fujii, M; Takahashi, M; Miyashita, T

    1978-05-01

    An electron microscopic observation on a pancreatic tumor removed from a 34-year-old woman revealed the fine structural morphology of a functional beta cell adenoma. Characteristic PAS positive crystalline structures were frequently observed in the cytoplasm of the tumor cells. They were not bounded by a membrane and had a rectangular or irregular hexagonal shape. Highly regular patterns were seen as such as lattice or honeycomb and parallel ripple structures. They are similar to the Reinke's crystal or crystalline structures reported in human hepatocytes suffering from several different diseases and considered as a protein-carbohydrate complex. Occasionally, small paracrystalline structures appeared to indicate an immature type of these structures in the opaque fine fibrillar mass. Crystalline or paracrystalline structures were not detected in the normal pancreatic tissue removed with the tumor from the patient.

  12. Electron Microscopy to Correlate Cell Structure and Biochemical Activity

    Science.gov (United States)

    1993-03-10

    Plasmodium coatneyi-infected rhesus monkeys: a primate model for human cerebral malaria. Memorias do Instituto Osvald Cruz (In Press). 24. Sim, K.L...P. coatney1 and found th.’t cvtoadherence of PRBC to ei.dothelial cells is a consistent feature of infections with this primate parasite. Cerebral ...Malaria; iaraunoe loct ror.-micros.’opy ; Chemotherapy; DFO; Cerebral malaria; HA 1 17 SECURITY CLASSIFICATION Of REPORT Unclass1 fled 1

  13. Appearance of Human Plasma Cells Following Differentiation of Human B Cells in NOD/SCID Mouse Spleen

    Directory of Open Access Journals (Sweden)

    Kentaro Kikuchi

    2003-01-01

    Full Text Available Relatively little is known for the differentiation and maturation process of human B cells to plasma cells. This is particularly important in reconstitution work involving transfer of autoantibodies. To address this issue, we transplanted human peripheral blood mononuclear cells (PBMC directly into the spleen of irradiated NOD/SCID mice depleted of natural killer cell activity. Within 6 weeks, naïve B cells differentiated into memory B cells and, importantly, the numbers of human CD138+ plasma cells in spleen increased by 100 fold after transplantation. Plasma cell numbers correlated with the detection of human IgM and IgG in serum, indicating that human B cells had differentiated into mature plasma cells in the murine spleen. In addition to CD19+ plasma cells, a distinct CD19- plasma cell population was detected, suggesting that downregulation of CD19 associated with maturation of plasma cells occurred. When purified human B cells were transplanted, those findings were not observed. Our results indicate that differentiation and maturation of human B cells and plasma cells can be investigated by transplantation of human PBMC into the spleen of NOD/SCID mice. The model will be useful for studying the differentiation of human B cells and generation of plasma cells.

  14. Human somatic cell nuclear transfer is alive and well.

    Science.gov (United States)

    Cibelli, Jose B

    2014-06-05

    In this issue, Chung et al. (2014) generate human embryonic stem cells by fusing an adult somatic cell to a previously enucleated human oocyte, in agreement with recent reports by the Mitalipov and Egli groups. We can now safely say that human somatic cell nuclear transfer is alive and well.

  15. Proteasome Particle-Rich Structures Are Widely Present in Human Epithelial Neoplasms: Correlative Light, Confocal and Electron Microscopy Study

    OpenAIRE

    2011-01-01

    A novel cytoplasmic structure has been recently characterized by confocal and electron microscopy in H. pylori-infected human gastric epithelium, as an accumulation of barrel-like proteasome reactive particles colocalized with polyubiquitinated proteins, H. pylori toxins and the NOD1 receptor. This proteasome particle-rich cytoplasmic structure (PaCS), a sort of focal proteasome hyperplasia, was also detected in dysplastic cells and was found to be enriched in SHP2 and ERK proteins, known to ...

  16. The association between human papillomavirus and oropharyngeal squamous cell Carcinoma

    DEFF Research Database (Denmark)

    Walvik, Lena; Svensson, Amanda Björk; Friborg, Jeppe

    2016-01-01

    There is emerging evidence of the association between human papillomavirus and a subset of head and neck cancers. However, the role of human papillomavirus as a causal factor is still debated. This review addresses the association between human papillomavirus and oropharyngeal squamous cell...... of well-defined premalignant lesions. However, a causal relationship between human papillomavirus infection and oropharyngeal squamous cell carcinoma seems evident....

  17. Fundamental electronic mechanisms limiting the performance of solar cells

    Science.gov (United States)

    Lindholm, F. A.; Sah, C.-T.

    1977-01-01

    Attention is focused on distortion in the energy band, and carrier recombination and generation rates (lifetimes), as the two dominant mechanisms. Spatial dependences associated with these two mechanisms, in the direction normal to the surface illuminated by the sun and in the direction tangential to that surface, are also emphasized as crucial factors in governing the efficiency of solar cells. Electronic parameters for the set of differential equations characterizing transport, recombination, and generation of carriers, and interband and band-bound transition rates, are studied.

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

    Science.gov (United States)

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

    2013-03-01

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

  19. The Relevancy of Graduate Curriculum to Human Resource Professionals' Electronic Communication.

    Science.gov (United States)

    Hoell, Robert C.; Henry, Gordon O.

    2003-01-01

    Electronic communications of human resource professionals and the content of 23 university human resource management courses were categorized using the Human Resource Certification Institute's body of knowledge. Differences between proportion of topics discussed and topics covered in curricula suggest some topics are over- or undertaught.…

  20. Scanning electron microscope studies of human metaphase chromosomes.

    Science.gov (United States)

    Shemilt, L A; Estandarte, A K C; Yusuf, M; Robinson, I K

    2014-03-06

    Scanning electron microscopy (SEM) is used to evaluate potential chromosome preparations and staining methods for application in high-resolution three-dimensional X-ray imaging. Our starting point is optical fluorescence microscopy, the standard method for chromosomes, which only gives structural detail at the 200 nm scale. In principle, with suitable sample preparation protocols, including contrast enhancing staining, the surface structure of the chromosomes can be viewed at the 1 nm level by SEM. Here, we evaluate a heavy metal nucleic-acid-specific stain, which gives strong contrast in the backscattered electron signal. This study uses SEM to examine chromosomes prepared in different ways to establish a sample preparation protocol for X-rays. Secondary electron and backscattered electron signals are compared to evaluate the effectiveness of platinum-based stains used to enhance the contrast.

  1. Glycomics of human embryonic stem cells and human induced pluripotent stem cells.

    Science.gov (United States)

    Furukawa, Jun-Ichi; Okada, Kazue; Shinohara, Yasuro

    2016-10-01

    Most cells are coated by a dense glycocalyx composed of glycoconjugates such as glycosphingolipids, glycoproteins, and proteoglycans. The overall glycomic profile is believed to be crucial for the diverse roles of glycans, which are mediated by specific interactions that regulate cell-cell adhesion, the immune response, microbial pathogenesis, and other cellular events. Many cell surface markers were discovered and identified as glycoconjugates such as stage-specific embryonic antigen, Tra-1-60/81 and various other cell surface molecules (e.g., cluster of differentiation). Recent progress in the development of analytical methodologies and strategies has begun to clarify the cellular glycomics of various cells including human embryonic stem cells (hESCs) and human induced pluripotent stem cells (hiPSCs). The glycomic profiles of these cells are highly cell type-specific and reflect cellular alterations, such as development, differentiation and cancerous change. In this mini review, we briefly summarize the glycosylation spectra specific to hESCs and hiPSCs, which cover glycans of all major glycoconjugates (i.e., glycosphingolipids, N- and O-glycans of glycoproteins, and glycosaminoglycans) and free oligosaccharides.

  2. Isolation and characterization of human spermatogonial stem cells

    Directory of Open Access Journals (Sweden)

    Liu Shixue

    2011-10-01

    Full Text Available Abstract Background To isolate and characterization of human spermatogonial stem cells from stem spermatogonium. Methods The disassociation of spermatogonial stem cells (SSCs were performed using enzymatic digestion of type I collagenase and trypsin. The SSCs were isolated by using Percoll density gradient centrifugation, followed by differential surface-attachment method. Octamer-4(OCT4-positive SSC cells were further identified using immunofluorescence staining and flow cytometry technques. The purity of the human SSCs was also determined, and a co-culture system for SSCs and Sertoli cells was established. Results The cell viability was 91.07% for the suspension of human spermatogonial stem cells dissociated using a two-step enzymatic digestion process. The cells isolated from Percoll density gradient coupled with differential surface-attachement purification were OCT4 positive, indicating the cells were human spermatogonial stem cells. The purity of isolated human spermatogonial stem cells was 86.7% as assessed by flow cytometry. The isolated SSCs were shown to form stable human spermatogonial stem cell colonies on the feeder layer of the Sertoli cells. Conclusions The two-step enzyme digestion (by type I collagenase and trypsin process is an economical, simple and reproducible technique for isolating human spermatogonial stem cells. With little contamination and less cell damage, this method facilitates isolated human spermatogonial stem cells to form a stable cell colony on the supporting cell layer.

  3. Enhancement of radiation response in human hepatocarcinoma cells by Metformin

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Eun Ho; Kim, Won Woo; Kim, Joon; Jung, Won Gyun [Division of heavy ion clinical research, Korea University, Seoul (Korea, Republic of); Jeong, Jae Hoon; Jeong, Youn Kyoung; Kim, Mi Sook [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2012-11-15

    Metformin (1, 1-dimethylbiguanide hydrochloride), the most widely used drug to treat type 2 diabetic patients under benefit good tolerability profile and low cost, has sparked keen interest as potential anticancer agent. Preclinical studies showed that the primary mechanism of action of metformin is through its ability to activate AMP-activated protein kinase (AMPK). Metformin inhibits complex 1 in the mitochondrial electron transport chain, leading to an increase in the AMP-to-ATP ratio, then, phospholylated AMPK increase energy generation or suppress energy consumption and then, inhibits cell growth. However, important caveat in direct action theory of metformin is that millimorlar range, effective dose for inhibition tumor cell growth in vitro, cannot be achieved in patients. This is probably because metformin enter cells through the organic cation transporters OCT1 and OCT2, which is lowly expressed in human cells except liver and adipose cells. dependent pathway rather than through direct effects of the tumor cells. We analyzed combination effect of metformin and radiation focusing to HCC cell lines, which theoretically express high organic cation transporters, producing high centration of metformin in tumor cells. The purpose of this study is to investigate whether metformin had anti-tumor effects when combined with radiation as radiosensitizer in HCC. The results showed that metformin increased radiosensitizing efficacy in HCC cells , as well as in Huh7 xenograft mouse models. Interestingly, metformin effectively sensitizes IR-induced apoptosis in HCC through upregulation of cleaved PARP and caspase3 and increase synergically on DNA damage response with combined treatment.HCC, suggesting potential usefulness of combined therapy of metformin together with radiation for HCC cancer therapy.

  4. Cell entry by human pathogenic arenaviruses.

    Science.gov (United States)

    Rojek, Jillian M; Kunz, Stefan

    2008-04-01

    The arenaviruses Lassa virus (LASV) in Africa and Machupo (MACV), Guanarito (GTOV) and Junin viruses (JUNV) in South America cause severe haemorrhagic fevers in humans with fatality rates of 15-35%. The present review focuses on the first steps of infection with human pathogenic arenaviruses, the interaction with their cellular receptor molecules and subsequent entry into the host cell. While similarities exist in genomic organization, structure and clinical disease caused by pathogenic Old World and New World arenaviruses these pathogens use different primary receptors. The Old World arenaviruses employ alpha-dystroglycan, a cellular receptor for proteins of the extracellular matrix, and the human pathogenic New World arenaviruses use the cellular cargo receptor transferrin receptor 1. While the New World arenavirus JUNV enters cells via clathrin-dependent endocytosis, evidence occurred for clathrin-independent entry of the prototypic Old World arenavirus lymphocytic choriomeningitis virus. Upon internalization, arenaviruses are delivered to the endosome, where pH-dependent membrane fusion is mediated by the envelope glycoprotein (GP). While arenavirus GPs share characteristics with class I fusion GPs of other enveloped viruses, unusual mechanistic features of GP-mediated membrane fusion have recently been discovered for arenaviruses with important implications for viral entry.

  5. Direct Methanol Fuel Cell Prototype Demonstration for Consumer Electronics Applications

    Energy Technology Data Exchange (ETDEWEB)

    Carlstrom, Charles, M., Jr.

    2009-07-07

    This report is the final technical report for DOE Program DE-FC36-04GO14301 titled “Direct Methanol Fuel Cell Prototype Demonstration for Consumer Electronics Applications”. Due to the public nature of this report some of the content reported in confidential reports and meetings to the DOE is not covered in detail in this report and some of the content has been normalized to not show actual values. There is a comparison of the projects accomplishments with the objectives, an overview of some of the key subsystem work, and a review of the three levels of prototypes demonstrated during the program. There is also a description of the eventual commercial product and market this work is leading towards. The work completed under this program has significantly increased the understanding of how Direct Methanol Fuel Cells (DMFC) can be deployed successfully to power consumer electronic devices. The prototype testing has demonstrated the benefits a direct methanol fuel cell system has over batteries typically used for powering consumer electronic devices. Three generations of prototypes have been developed and tested for performance, robustness and life. The technologies researched and utilized in the fuel cell stack and related subsystems for these prototypes are leveraged from advances in other industries such as the hydrogen fueled PEM fuel cell industry. The work under this program advanced the state of the art of direct methanol fuel cells. The system developed by MTI micro fuel cells aided by this program differs significantly from conventional DMFC designs and offers compelling advantages in the areas of performance, life, size, and simplicity. The program has progressed as planned resulting in the completion of the scope of work and available funding in December 2008. All 18 of the final P3 prototypes builds have been tested and the results showed significant improvements over P2 prototypes in build yield, initial performance, and durability. The systems have

  6. Markers of T Cell Senescence in Humans

    Directory of Open Access Journals (Sweden)

    Weili Xu

    2017-08-01

    Full Text Available Many countries are facing the aging of their population, and many more will face a similar obstacle in the near future, which could be a burden to many healthcare systems. Increased susceptibility to infections, cardiovascular and neurodegenerative disease, cancer as well as reduced efficacy of vaccination are important matters for researchers in the field of aging. As older adults show higher prevalence for a variety of diseases, this also implies higher risk of complications, including nosocomial infections, slower recovery and sequels that may reduce the autonomy and overall quality of life of older adults. The age-related effects on the immune system termed as “immunosenescence” can be exemplified by the reported hypo-responsiveness to influenza vaccination of the elderly. T cells, which belong to the adaptive arm of the immune system, have been extensively studied and the knowledge gathered enables a better understanding of how the immune system may be affected after acute/chronic infections and how this matters in the long run. In this review, we will focus on T cells and discuss the surface and molecular markers that are associated with T cell senescence. We will also look at the implications that senescent T cells could have on human health and diseases. Finally, we will discuss the benefits of having these markers for investigators and the future work that is needed to advance the field of T cell senescence markers.

  7. Human embryonic stem cells and microenvironment

    Directory of Open Access Journals (Sweden)

    Banu İskender

    2014-09-01

    Full Text Available Human embryonic stem cells (hESCs possess a great potential in the field of regenerative medicine by their virtue of pluripotent potential with indefinite proliferation capabilities. They can self renew themselves and differentiate into three embryonic germ layers. Although they are conventionally grown on mitotically inactivated mouse feeder cells, there are in vitro culture systems utilizing feeder cells of human origin in order to prevent cross-species contamination. Recently established in vitro culture systems suggested that direct interaction with feeder cells is not necessary but rather attachment to a substrate is required to ensure long-term, efficient hESC culture in vitro. This substrate is usually composed of a mixture of extracellular matrix components representing in vivo natural niche. In hESC biology, the mechanism of interaction of hESCs with extracellular matrix molecules remained insufficiently explored area of research due to their transient nature of interaction with the in vivo niche. However, an in vitro culture system established using extracellular matrix molecules may provide a safer alternative to culture systems with feeder cells while paving the way to Good Manufacturing Practice-GMP production of hESCs for therapeutic purposes. Therefore, it is essential to study the interaction of extracellular matrix molecules with hESCs in order to standardize in vitro culture systems for large-scale production of hESCs in a less labor-intensive way. This would not only provide valuable information regarding the mechanisms that control pluripotency but also serve to dissect the molecular signaling pathways of directed differentiation for prospective therapeutic applications in the future. J Clin Exp Invest 2014; 5 (3: 486-495

  8. The adult macaque spinal cord central canal zone contains proliferative cells and closely resembles the human.

    Science.gov (United States)

    Alfaro-Cervello, Clara; Cebrian-Silla, Arantxa; Soriano-Navarro, Mario; Garcia-Tarraga, Patricia; Matías-Guiu, Jorge; Gomez-Pinedo, Ulises; Molina Aguilar, Pilar; Alvarez-Buylla, Arturo; Luquin, Maria-Rosario; Garcia-Verdugo, Jose Manuel

    2014-06-01

    The persistence of proliferative cells, which could correspond to progenitor populations or potential cells of origin for tumors, has been extensively studied in the adult mammalian forebrain, including human and nonhuman primates. Proliferating cells have been found along the entire ventricular system, including around the central canal, of rodents, but little is known about the primate spinal cord. Here we describe the central canal cellular composition of the Old World primate Macaca fascicularis via scanning and transmission electron microscopy and immunohistochemistry and identify central canal proliferating cells with Ki67 and newly generated cells with bromodeoxyuridine incorporation 3 months after the injection. The central canal is composed of uniciliated, biciliated, and multiciliated ependymal cells, astrocytes, and neurons. Multiciliated ependymal cells show morphological characteristics similar to multiciliated ependymal cells from the lateral ventricles, and uniciliated and biciliated ependymal cells display cilia with large, star-shaped basal bodies, similar to the Ecc cells described for the rodent central canal. Here we show that ependymal cells with one or two cilia, but not multiciliated ependymal cells, proliferate and give rise to new ependymal cells that presumably remain in the macaque central canal. We found that the infant and adult human spinal cord contains ependymal cell types that resemble those present in the macaque. Interestingly, a wide hypocellular layer formed by bundles of intermediate filaments surrounded the central canal both in the monkey and in the human, being more prominent in the stenosed adult human central canal.

  9. Sensing lymphoma cells based on a cell-penetrating/apoptosis-inducing/electron-transfer peptide probe

    Energy Technology Data Exchange (ETDEWEB)

    Sugawara, Kazuharu, E-mail: kzsuga@maebashi-it.ac.jp [Maebashi Institute of Technology, Gunma 371-0816 (Japan); Shinohara, Hiroki; Kadoya, Toshihiko [Maebashi Institute of Technology, Gunma 371-0816 (Japan); Kuramitz, Hideki [Department of Environmental Biology and Chemistry, Graduate School of Science and Engineering for Research, University of Toyama, Toyama 930-8555 (Japan)

    2016-06-14

    To electrochemically sense lymphoma cells (U937), we fabricated a multifunctional peptide probe that consists of cell-penetrating/apoptosis-inducing/electron-transfer peptides. Electron-transfer peptides derive from cysteine residue combined with the C-terminals of four tyrosine residues (Y{sub 4}). A peptide whereby Y{sub 4}C is bound to the C-terminals of protegrin 1 (RGGRLCYCRRRFCVCVGR-NH{sub 2}) is known to be an apoptosis-inducing agent against U937 cells, and is referred to as a peptide-1 probe. An oxidation response of the peptide-1 probe has been observed due to a phenolic hydroxyl group, and this response is decreased by the uptake of the peptide probe into the cells. To improve the cell membrane permeability against U937 cells, the RGGR at the N-terminals of the peptide-1 probe was replaced by RRRR (peptide-2 probe). In contrast, RNRCKGTDVQAWY{sub 4}C (peptide-3 probe), which recognizes ovalbumin, was constructed as a control. Compared with the other probes, the change in the peak current of the peptide-2 probe was the greatest at low concentrations and occurred in a short amount of time. Therefore, the cell membrane permeability of the peptide-2 probe was increased based on the arginine residues and the apoptosis-inducing peptides. The peak current was linear and ranged from 100 to 1000 cells/ml. The relative standard deviation of 600 cells/ml was 5.0% (n = 5). Furthermore, the membrane permeability of the peptide probes was confirmed using fluorescent dye. - Highlights: • We constructed a multifunctional peptide probe for the electrochemical sensing of lymphoma cells. • The peptide probe consists of cell-penetrating/apoptosis-inducing/electron-transfer peptides. • The electrode response of the peptide probe changes due to selective uptake into the cells.

  10. In vitro effects of chitosan nanoparticles on proliferation of human gastric carcinoma cell line MGC803 cells

    Institute of Scientific and Technical Information of China (English)

    Li-Feng Qi; Zi-Rong Xu; Yan Li; Xia Jiang; Xin-Yan Han

    2005-01-01

    AIM: To investigate the effects of chitosan nanoparticles on proliferation of human gastric carcinoma cell line MGC803 in vitro and the possible mechanisms involved.METHODS: Chitosan nanoparticles were characterized by particle size, zeta potential, and morphology. After treatment with various concentrations of chitosan nanoparticles (25, 50, 75, 100 μg/mL) at various time intervals, cell proliferation, ultrastructural changes, DNA fragmentation, mitochondrial membrane potential (MMP),cell cycle phase distribution and apoptotic peaks of MGC803 cells were analyzed by MTT assay, electron microscopy,DNA agarose gel electrophoresis, and flow cytometry.RESULTS: Chitosan nanoparticles exhibited a small particle size as 65 nm and a high surface charge as 52 mV.Chitosan nanoparticles markedly inhibited cell proliferation of MGC803 cells with an IC50 value of 5.3 μg/mL 48 h after treatment. After treatment with chitosan nanoparticles,the typical necrotic cell morphology was observed by electron microscopy, a typical DNA degradation associated with necrosis was determined by DNA agarose electrophoresis.Flow cytometry showed the loss of MMP and occurrence of apoptosis in chitosan nanoparticles-treated cells.CONCLUSION: Chitosan nanoparticles effectively inhibit the proliferation of human gastric carcinoma cell line MGC803 in vitro through multiple mechanisms, and may be a beneficial agent against human carcinoma.

  11. Biochemical and phenotypic characterization of human basophilic cells derived from dispersed fetal liver with murine T cell factors

    Energy Technology Data Exchange (ETDEWEB)

    Seldin, D.C.; Caulfield, J.P.; Hein, A.; Osathanondh, R.; Nabel, G.; Schlossman, S.F.; Stevens, R.L.; Austen, K.F.

    1986-03-15

    Metachromatically granulated cells were generated from human fetal liver stem cells cultured in heterologous mouse conditioned medium rich in interleukin 3. After 2 to 3 wk of culture with biweekly changes of medium and selection of nonadherent cells, all cells present in five cultures had cytoplasmic granules. Ultrastructurally, many granules contained fibrillar material or electron-dense cores with fibrils and vesicular fragments. In addition, the granules of many cells were filled with electron-dense material, which in some cases had a fine structure consisting of concentric whorls or a reticular pattern. Analysis of high-affinity IgE receptors on the cultured cells by flow cytometry demonstrated a unimodel fluorescence pattern, suggesting that most cells were in the basophil or mast cell lineage. The cells contained 52 ng/10/sup 6/ cells of histamine and incorporated (/sup 35/S)sulfate at an average rate of 31,300 cpm/10/sup 6/ cells/4 hr into 175,000 m.w. chondroitin sulfate A proteoglycans. Upon activation with 1 ..mu..M calcium ionophore A23187, the cultured cells released 53% of their cell-associated histamine and metabolized arachidonic acid to 15.0 ng/10/sup 6/ cells of immunoreactive leukotriene C/sub 4/ equivalents, 0.5 ng/10/sup 6/ cells of leukotriene B/sub 4/, and 3.1 ng/10/sup 6/ cells of prostaglandin D/sub 2/ (means, n = 3). Thus, stem cells present in human fetal liver give rise, as do stem cells in mouse fetal liver, to metachromatically granulated cells when cultured in the presence of mouse interleukin 3.

  12. One-Dimensional Electron Transport Layers for Perovskite Solar Cells

    Directory of Open Access Journals (Sweden)

    Ujwal K. Thakur

    2017-04-01

    Full Text Available The electron diffusion length (Ln is smaller than the hole diffusion length (Lp in many halide perovskite semiconductors meaning that the use of ordered one-dimensional (1D structures such as nanowires (NWs and nanotubes (NTs as electron transport layers (ETLs is a promising method of achieving high performance halide perovskite solar cells (HPSCs. ETLs consisting of oriented and aligned NWs and NTs offer the potential not merely for improved directional charge transport but also for the enhanced absorption of incoming light and thermodynamically efficient management of photogenerated carrier populations. The ordered architecture of NW/NT arrays affords superior infiltration of a deposited material making them ideal for use in HPSCs. Photoconversion efficiencies (PCEs as high as 18% have been demonstrated for HPSCs using 1D ETLs. Despite the advantages of 1D ETLs, there are still challenges that need to be overcome to achieve even higher PCEs, such as better methods to eliminate or passivate surface traps, improved understanding of the hetero-interface and optimization of the morphology (i.e., length, diameter, and spacing of NWs/NTs. This review introduces the general considerations of ETLs for HPSCs, deposition techniques used, and the current research and challenges in the field of 1D ETLs for perovskite solar cells.

  13. One-Dimensional Electron Transport Layers for Perovskite Solar Cells

    Science.gov (United States)

    Thakur, Ujwal K.; Kisslinger, Ryan; Shankar, Karthik

    2017-01-01

    The electron diffusion length (Ln) is smaller than the hole diffusion length (Lp) in many halide perovskite semiconductors meaning that the use of ordered one-dimensional (1D) structures such as nanowires (NWs) and nanotubes (NTs) as electron transport layers (ETLs) is a promising method of achieving high performance halide perovskite solar cells (HPSCs). ETLs consisting of oriented and aligned NWs and NTs offer the potential not merely for improved directional charge transport but also for the enhanced absorption of incoming light and thermodynamically efficient management of photogenerated carrier populations. The ordered architecture of NW/NT arrays affords superior infiltration of a deposited material making them ideal for use in HPSCs. Photoconversion efficiencies (PCEs) as high as 18% have been demonstrated for HPSCs using 1D ETLs. Despite the advantages of 1D ETLs, there are still challenges that need to be overcome to achieve even higher PCEs, such as better methods to eliminate or passivate surface traps, improved understanding of the hetero-interface and optimization of the morphology (i.e., length, diameter, and spacing of NWs/NTs). This review introduces the general considerations of ETLs for HPSCs, deposition techniques used, and the current research and challenges in the field of 1D ETLs for perovskite solar cells. PMID:28468280

  14. Identification of a candidate stem cell in human gallbladder

    Directory of Open Access Journals (Sweden)

    Rohan Manohar

    2015-05-01

    In conclusion, we have isolated a distinct clonogenic population of epithelial cells from primary human fetal gallbladder with stem cell characteristics and found it to be unique compared to IHBD cells.

  15. Cell cycle regulation by glucosamine in human pulmonary epithelial cells.

    Science.gov (United States)

    Chuang, Kun-Han; Lu, Chih-Shen; Kou, Yu Ru; Wu, Yuh-Lin

    2013-04-01

    Airway epithelial cells play an important role against intruding pathogens. Glucosamine, a commonly used supplemental compound, has recently begun to be regarded as a potential anti-inflammatory molecule. This study aimed to uncover how glucosamine impacts on cellular proliferation in human alveolar epithelial cells (A549) and bronchial epithelial cells (HBECs). With trypan blue-exclusion assay, we observed that glucosamine (10, 20, 50 mM) caused a decrease in cell number at 24 and 48 h; with a flow cytometric analysis, we also noted an enhanced cell accumulation within the G(0)/G(1) phase at 24 h and induction of late apoptosis at 24 and 48 h by glucosamine (10, 20, 50 mM) in A549 cells and HBECs. Examination of phosphorylation in retinoblastoma (Rb) protein, we found an inhibitory effect by glucosamine at 20 and 50 mM. Glucosamine at 50 mM was demonstrated to elevate both the mRNA and protein expression of p53 and heme oxygenase-1 (HO-1), but also caused a reduction in p21 protein expression. In addition, glucosamine attenuated p21 protein stability via the proteasomal proteolytic pathway, as well as inducing p21 nuclear accumulation. Altogether, our results suggest that a high dose of glucosamine may inhibit cell proliferation through apoptosis and disturb cell cycle progression with a halt at G(0)/G(1) phase, and that this occurs, at least in part, by a reduction in Rb phosphorylation together with modulation of p21, p53 and HO-1 expression, and nuclear p21 accumulation.

  16. Detecting particles with cell phones: the Distributed Electronic Cosmic-ray Observatory

    CERN Document Server

    Vandenbroucke, Justin; Karn, Peter; Meehan, Matthew; Plewa, Matthew; Ruggles, Tyler; Schultz, David; Peacock, Jeffrey; Simons, Ariel Levi

    2015-01-01

    In 2014 the number of active cell phones worldwide for the first time surpassed the number of humans. Cell phone camera quality and onboard processing power (both CPU and GPU) continue to improve rapidly. In addition to their primary purpose of detecting photons, camera image sensors on cell phones and other ubiquitous devices such as tablets, laptops and digital cameras can detect ionizing radiation produced by cosmic rays and radioactive decays. While cosmic rays have long been understood and characterized as a nuisance in astronomical cameras, they can also be identified as a signal in idle camera image sensors. We present the Distributed Electronic Cosmic-ray Observatory (DECO), a platform for outreach and education as well as for citizen science. Consisting of an app and associated database and web site, DECO harnesses the power of distributed camera image sensors for cosmic-ray detection.

  17. Spheroid culture for enhanced differentiation of human embryonic stem cells to hepatocyte-like cells.

    Science.gov (United States)

    Subramanian, Kartik; Owens, Derek Jason; Raju, Ravali; Firpo, Meri; O'Brien, Timothy D; Verfaillie, Catherine M; Hu, Wei-Shou

    2014-01-15

    Stem cell-derived hepatocyte-like cells hold great potential for the treatment of liver disease and for drug toxicity screening. The success of these applications hinges on the generation of differentiated cells with high liver specific activities. Many protocols have been developed to guide human embryonic stem cells (hESCs) to differentiate to the hepatic lineage. Here we report cultivation of hESCs as three-dimensional aggregates that enhances their differentiation to hepatocyte-like cells. Differentiation was first carried out in monolayer culture for 20 days. Subsequently cells were allowed to self-aggregate into spheroids. Significantly higher expression of liver-specific transcripts and proteins, including Albumin, phosphoenolpyruvate carboxykinase, and asialoglycoprotein receptor 1 was observed. The differentiated phenotype was sustained for more than 2 weeks in the three-dimensional spheroid culture system, significantly longer than in monolayer culture. Cells in spheroids exhibit morphological and ultrastructural characteristics of primary hepatocytes by scanning and transmission electron microscopy in addition to mature functions, such as biliary excretion of metabolic products and cytochrome P450 activities. This three-dimensional spheroid culture system may be appropriate for generating high quality, functional hepatocyte-like cells from ESCs.

  18. CD34-positive interstitial cells of the human detrusor

    DEFF Research Database (Denmark)

    Rasmussen, Helle; Hansen, Alastair; Smedts, Frank;

    2007-01-01

    and intermingling with individual muscle fasicles. Morphologically and immunohistochemically, they show no neurogenic, endothelial or mast cell differentiation. Transmission electron microscopy (TEM) showed the presence of interstitial cells with a round-to-oval nucleus, sparse perinuclear cytoplasm and long...

  19. Effects of Electron-Beam Irradiation on Buccal-Cell DNA

    OpenAIRE

    2003-01-01

    Buccal cells were collected from 29 participants, by use of mouthwash rinses, and were split into equal aliquots, with one aliquot irradiated by electron-beam (E-beam) irradiation equivalent to the sterilizing dosage used by the U.S. Postal Service and the other left untreated. Aliquots were extracted and tested for DNA yields (e.g., TaqMan assay for quantifying human genomic DNA), genomic integrity, and amplification-based analysis of genetic variants (e.g., single-nucleotide polymorphisms [...

  20. Generation of Functional Lentoid Bodies From Human Induced Pluripotent Stem Cells Derived From Urinary Cells.

    Science.gov (United States)

    Fu, Qiuli; Qin, Zhenwei; Jin, Xiuming; Zhang, Lifang; Chen, Zhijian; He, Jiliang; Ji, Junfeng; Yao, Ke

    2017-01-01

    The pathological mechanisms underlying cataract formation remain largely unknown on account of the lack of appropriate in vitro cellular models. The aim of this study is to develop a stable in vitro system for human lens regeneration using pluripotent stem cells. Isolated human urinary cells were infected with four Yamanaka factors to generate urinary human induced pluripotent stem cells (UiPSCs), which were induced to differentiate into lens progenitor cells and lentoid bodies (LBs). The expression of lens-specific markers was examined by real-time PCR, immunostaining, and Western blotting. The structure and magnifying ability of LBs were investigated using transmission electron microscopy and observing the magnification of the letter "X," respectively. We developed a "fried egg" differentiation method to generate functional LBs from UiPSCs. The UiPSC-derived LBs exhibited crystalline lens-like morphology and a transparent structure and expressed lens-specific markers αA-, αB-, β-, and γ-crystallin and MIP. During LB differentiation, the placodal markers SIX1, EYA1, DLX3, PAX6, and the specific early lens markers SOX1, PROX1, FOXE3, αA-, and αB-crystallin were observed at certain time points. Microscopic examination revealed the presence of lens epithelial cells adjacent to the lens capsule as well as both immature and mature fiber-like cells. Optical analysis further demonstrated the magnifying ability (1.7×) of the LBs generated from UiPSCs. Our study provides the first evidence toward generating functional LBs from UiPSCs, thereby establishing an in vitro system that can be used to study human lens development and cataractogenesis and perhaps even be useful for drug screening.

  1. Human embryonic stem cells and patent protection

    Directory of Open Access Journals (Sweden)

    Radovanović Sanja M.

    2015-01-01

    Full Text Available Given the importance of biotechnological research in modern diagnostics and therapeutics, on the one hand, and stimulative function of a patent, on the other hand, this work deals with the question of the possibility of pa-tent protection of human embryonic stem cells. Taking into account that this is a biotechnological invention, the key question that this paper highlights is the interpretation of the provisions of their patentability. Namely, thanks to the advanced methods of isolation, purification and preparation for implementation, modern patent systems do not exclude a priori living organisms from patent protection. Therefore, the analysis of representative administrative decisions or court rulings sought to define the criteria that would be applied in order to give patent protection to a certain biotechnological invention (stem cells while others do not.

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

    OpenAIRE

    2008-01-01

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

  3. Restriction of human adenovirus replication in Chinese hamster cell lines and their hybrids with human cells.

    Science.gov (United States)

    Radna, R L; Foellmer, B; Feldman, L A; Francke, U; Ozer, H L

    1987-11-01

    We have found that the replication of human adenovirus (Ad2) is restricted in multiple Chinese hamster cell lines including CHO and V79. The major site of restriction involves differential accumulation of late viral proteins as demonstrated by immunofluorescence assay and polyacrylamide gel electrophoresis with and without prior immunoprecipitation. Synthesis of fiber and penton base are markedly reduced, whereas others, such as the 100K polypeptide, are synthesized efficiently. This pattern of restriction is similar to that previously reported for Ad2 infection of several monkey cell lines; however, the restriction is more marked in the Chinese hamster cell lines. The restriction is most likely due to a deficient cellular function since stable cell hybrids between V79 or CHO and human cells are permissive for virus replication. By analysis of a series of hybrids with reduced numbers of human chromosomes, fiber synthesis was correlated with the presence of the short arm of human chromosome 3. More hybrids showed restoration of fiber synthesis than production of progeny virus, suggesting that more than one unlinked function is required for the latter.

  4. Human ceruloplasmin. Intramolecular electron transfer kinetics and equilibration

    DEFF Research Database (Denmark)

    Farver, O; Bendahl, L; Skov, L K

    1999-01-01

    Pulse radiolytic reduction of disulfide bridges in ceruloplasmin yielding RSSR(-) radicals induces a cascade of intramolecular electron transfer (ET) processes. Based on the three-dimensional structure of ceruloplasmin identification of individual kinetically active disulfide groups and type 1 (T1...... and indeed electron equilibration between T1A and the trinuclear copper center in the domain 1-6 interface takes place with a rate constant of 2.9 +/- 0.6 s(-1). The equilibrium constant is 0.17. Following reduction of T1A Cu(II), another ET process takes place between RSSR(-) and T1B copper(II) of domain 4...

  5. Phenotypic changes of human cells in human-rat liver during partial hepatectomy-induced regeneration

    Institute of Scientific and Technical Information of China (English)

    Yan Sun; Dong Xiao; Hong-An Li; Jin-Fang Jiang; Qing Li; Ruo-Shuang Zhang; Xi-Gu Chen

    2009-01-01

    AIM: To examine the human hepatic parenchymal and stromal components in rat liver and the phenotypic changes of human cells in liver of human-rat chimera (HRC) generated by in utero transplantation of human cells during partial hepatectomy (PHx)-induced liver regeneration. METHODS: Human hepatic parenchymal and stromal components and phenotypic changes of human cells during liver regeneration were examined by flow cytometry, in situ hybridization and immunohistochemistry. RESULTS: ISH analysis demonstrated human Alupositive cells in hepatic parenchyma and stroma of recipient liver. Functional human hepatocytes generated in this model potentially constituted human hepatic functional units with the presence of donor-derived human endothelial and biliary duct cells in host liver. Alpha fetoprotein (AFP)+, CD34+ and CD45+ cells were observed in the chimeric liver on day 10 after PHxinduced liver regeneration and then disappeared in PHx group, but not in non-PHx group, suggesting that dynamic phenotypic changes of human cells expressing AFP, CD34 and CD45 cells may occur during the chimeric liver regeneration. Additionally, immunostaining for human proliferating cell nuclear antigen (PCNA) showed that the number of PCNA-positive cells in the chimeric liver of PHx group was markedly increased, as compared to that of control group, indicating that donor-derived human cells are actively proliferated during PHx-induced regeneration of HRC liver.

  6. HIF induces human embryonic stem cell markers in cancer cells.

    Science.gov (United States)

    Mathieu, Julie; Zhang, Zhan; Zhou, Wenyu; Wang, Amy J; Heddleston, John M; Pinna, Claudia M A; Hubaud, Alexis; Stadler, Bradford; Choi, Michael; Bar, Merav; Tewari, Muneesh; Liu, Alvin; Vessella, Robert; Rostomily, Robert; Born, Donald; Horwitz, Marshall; Ware, Carol; Blau, C Anthony; Cleary, Michele A; Rich, Jeremy N; Ruohola-Baker, Hannele

    2011-07-01

    Low oxygen levels have been shown to promote self-renewal in many stem cells. In tumors, hypoxia is associated with aggressive disease course and poor clinical outcomes. Furthermore, many aggressive tumors have been shown to display gene expression signatures characteristic of human embryonic stem cells (hESC). We now tested whether hypoxia might be responsible for the hESC signature observed in aggressive tumors. We show that hypoxia, through hypoxia-inducible factor (HIF), can induce an hESC-like transcriptional program, including the induced pluripotent stem cell (iPSC) inducers, OCT4, NANOG, SOX2, KLF4, cMYC, and microRNA-302 in 11 cancer cell lines (from prostate, brain, kidney, cervix, lung, colon, liver, and breast tumors). Furthermore, nondegradable forms of HIFα, combined with the traditional iPSC inducers, are highly efficient in generating A549 iPSC-like colonies that have high tumorigenic capacity. To test potential correlation between iPSC inducers and HIF expression in primary tumors, we analyzed primary prostate tumors and found a significant correlation between NANOG-, OCT4-, and HIF1α-positive regions. Furthermore, NANOG and OCT4 expressions positively correlated with increased prostate tumor Gleason score. In primary glioma-derived CD133 negative cells, hypoxia was able to induce neurospheres and hESC markers. Together, these findings suggest that HIF targets may act as key inducers of a dynamic state of stemness in pathologic conditions.

  7. Effects of Shuanghuangbu on the total protein content and ultrastructure in cultured human periodontal ligament cells

    Institute of Scientific and Technical Information of China (English)

    许彦枝; 邹慧儒; 王小玲; 刘世正; 王永军

    2004-01-01

    Background Successful periodontal regeneration depends on the migration, proliferation and differentiation of periodontal ligament cells in periodontal defects. The total protein content and the ultrastructure demonstrate the metabolizability and activity of periodontal ligament cells. This study was conducted to observe the effects of Shuanghuangbu, a mixture of medicinal herbs, on the total protein content and the ultrastructure of human periodontal ligament cells.Methods Periodontal ligament cells were grown to confluence and then cultured in Dulbecco's modified eagle medium (DMEM) supplemented with Shuanghuangbu over the concentration range of 0 to 1000 μg/ml. The total protein content in cultured cells was determined by using Coommasie brilliant blue technique. Periodontal ligament cells were incubated in 0 and 100 μg/ml Shuanghuangbu decoction for 5 days, then observed through transmission electron microscope.Results The total protein content of human periodontal ligament cells increased in each experiment group added 10-1000 μg/ml Shuanghuangbu respectively, and the effect of 100 μg/ml was excellent. Under the transmission electron microscope, there were more rough endoplasmic reticulums and mitochodrias in the experiment group than those in the control group. Conclusion Shuanghuangbu stimulates the protein synthesis of human periodontal ligament cells and improves human periodontal ligament cells' metabolizability and activity.

  8. Scanning electron microscopy and electron probe microanalyses of the crystalline components of human and animal dental calculi.

    Science.gov (United States)

    LeGeros, R Z; Orly, I; LeGeros, J P; Gomez, C; Kazimiroff, J; Tarpley, T; Kerebel, B

    1988-03-01

    A review of the use of scanning electron microscopy (SEM) and electron probe microanalyses in the study of dental calculus showed that such studies provided confirmatory and supplementary data on the morphological features of human dental calculi but gave only limited information on the identity of the crystalline or inorganic components. This study aimed to explore the potential of combined SEM and microanalyses in the identification of the crystalline components of the human and animal dental calculi. Human and animal calculi were analyzed. Identification of the crystalline components were made based on the combined information of the morphology (SEM) and Ca/P molar ratios of the crystals with the morphology and Ca/P molar ratio of synthetic calcium phosphates (brushite or DCPD; octacalcium phosphate, OCP; Mg-substituted whitlockite, beta-TCMP; CO3-substituted apatite, (CHA); and calcite. SEM showed similarities in morphological features of human and animal dental calculi but differences in the forms of crystals present. Microanalyses and crystal morphology data suggested the presence of CaCO3 (calcite) and CHA in the animal (cat, dog, tiger) and of OCP, beta-TCMP and CHA in human dental calculi. X-ray diffraction and infrared (IR) absorption analyses confirmed these results. This exploratory study demonstrated that by taking into consideration what is known about the crystalline components of human and animal dental calculi, combined SEM and microanalyses can provide qualitative identification.

  9. Scanning electron microscopy and electron probe microanalyses of the crystalline components of human and animal dental calculi

    Energy Technology Data Exchange (ETDEWEB)

    LeGeros, R.Z.; Orly, I.; LeGeros, J.P.; Gomez, C.; Kazimiroff, J.; Tarpley, T.; Kerebel, B.

    1988-03-01

    A review of the use of scanning electron microscopy (SEM) and electron probe microanalyses in the study of dental calculus showed that such studies provided confirmatory and supplementary data on the morphological features of human dental calculi but gave only limited information on the identity of the crystalline or inorganic components. This study aimed to explore the potential of combined SEM and microanalyses in the identification of the crystalline components of the human and animal dental calculi. Human and animal calculi were analyzed. Identification of the crystalline components were made based on the combined information of the morphology (SEM) and Ca/P molar ratios of the crystals with the morphology and Ca/P molar ratio of synthetic calcium phosphates (brushite or DCPD; octacalcium phosphate, OCP; Mg-substituted whitlockite, beta-TCMP; CO/sub 3/-substituted apatite, (CHA); and calcite. SEM showed similarities in morphological features of human and animal dental calculi but differences in the forms of crystals present. Microanalyses and crystal morphology data suggested the presence of CaCO/sub 3/ (calcite) and CHA in the animal (cat, dog, tiger) and of OCP, beta-TCMP and CHA in human dental calculi. X-ray diffraction and infrared (IR) absorption analyses confirmed these results. This exploratory study demonstrated that by taking into consideration what is known about the crystalline components of human and animal dental calculi, combined SEM and microanalyses can provide qualitative identification.

  10. Derivation of human embryonic stem cells in defined conditions.

    Science.gov (United States)

    Ludwig, Tenneille E; Levenstein, Mark E; Jones, Jeffrey M; Berggren, W Travis; Mitchen, Erika R; Frane, Jennifer L; Crandall, Leann J; Daigh, Christine A; Conard, Kevin R; Piekarczyk, Marian S; Llanas, Rachel A; Thomson, James A

    2006-02-01

    We have previously reported that high concentrations of basic fibroblast growth factor (bFGF) support feeder-independent growth of human embryonic stem (ES) cells, but those conditions included poorly defined serum and matrix components. Here we report feeder-independent human ES cell culture that includes protein components solely derived from recombinant sources or purified from human material. We describe the derivation of two new human ES cell lines in these defined culture conditions.

  11. Effects of topographical surface modifications of electron beam melted Ti-6Al-4V titanium on human fetal osteoblasts.

    Science.gov (United States)

    Ponader, Sabine; Vairaktaris, Eleftherios; Heinl, Peter; Wilmowsky, Cornelius V; Rottmair, Andreas; Körner, Carolin; Singer, Robert F; Holst, Stefan; Schlegel, Karl A; Neukam, Friedrich W; Nkenke, Emeka

    2008-03-15

    The aim of the study was to assess the suitability of different Ti-6Al-4V surfaces produced by the electron beam melting (EBM) process as matrices for attachment, proliferation, and differentiation of human fetal osteoblasts (hFOB 1.19). Human osteoblasts were cultured in vitro on smooth and rough-textured Ti-6Al-4V alloy disks. By means of cell number and vitality and SEM micrographs cell attachment and proliferation were observed. The differentiation rate was examined by using quantitative real-time PCR analysis for the gene expression of alkaline phosphatase (ALP), type I collagen (Coll-I), bone sialoprotein (BSP) and osteocalcin (OC). After 3 days of incubation there was a significant higher vitality (p /= 56.9 microm) reduced proliferation of hFOB cells. Surface characteristics of titanium can easily be changed by EBM in order to further improve proliferation. (c) 2007 Wiley Periodicals, Inc.

  12. Manufacture and scanning electron microscopic observation of human dermis collagen membrane

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    @@ Introduction Collagen is a kind of biomacromolecule and can be used as cover material for burn wounds. In this article,we report the scanning electron microscopic observation of human dermis collagen membrane prepared by three methods.

  13. Introduction: characterization and functions of human T regulatory cells.

    Science.gov (United States)

    Romagnani, Sergio

    2005-06-01

    The field of human T regulatory (Treg) cells is a rapidly progressing, but still confused field of immunology. The effects of dendritic cell (DC) manipulation in Treg generation and the main features of human "natural" Treg cells, as well as of different populations of adaptive Treg subsets, are still partially unclear. However, it is clear that Treg cells play an important role in human diseases, such as autoimmune disorders, allergy, HIV infection, tumors and graft-versus-host disease.

  14. Effects of allitridi on cell cycle arrest of human gastric cancer cells

    Institute of Scientific and Technical Information of China (English)

    Min-Wen Ha; Rui Ma; Li-Ping Shun; Yue-Hua Gong; Yuan Yuan

    2005-01-01

    AIM: To determine the effect of allitridi on cell cycle of human gastric cancer (HGC) cell lines MGC803 and SGC7901 and its possible mechanism.METHODS: Trypan blue dye exclusion was used to evaluate the proliferation, inhibition of cells and damages of these cells were detected with electron microscope.Flow cytometry and cell mitotic index were used to analyze the change of cell cycle, immunohistochemistry, and RT-PCR was used to examine expression of the p21WAF1 gene.RESULTS: MGC803 cell growth was inhibited by allitridi with 24 h IC50 being 6.4 μg/mL. SGC7901 cell growth was also inhibited by allitridi with 24 h IC50 being 7.3 μg/mL.After being treated with allitridi at the concentration of 12 μg/mL for 24 h, cells were found to have direct cytotoxic effects, including broken cellular membrane, swollen and vesiculated mitochondria and rough endoplasmic reticula,and mass lipid droplet. When cells were treated with allitridi at the concentration of 3, 6, and 9 μg/mL for 24 h, the percentage of G0/G1 phase cells was decreased and that of G2/M phase cells was significantly increased (P = 0.002)compared with those in the group. When cells were treated with allitridi at the concentration of 6 μg/mL, cell mitotic index was much higher (P = 0.003) than that of control group, indicating that allitridi could cause gastric cancer cell arrest in M phase. Besides, the expression levels of p21WAF1 gene of MGC803 cells and p21WAF1 gene of SGC7901 cells were remarkably upregulated after treatment.CONCLUSION: Allitridi can cause gastric cancer cell arrest in M phase, and this may be one of the mechanisms for inhibiting cell proliferation. Effect of allitridi on cells in M phas e may be associated with the upregulation of p21WAF1 genes. This study provides experimental data for clinical use of allitridi in the treatment of gastric carcinoma.

  15. Human pancreatic cell autotransplantation following total pancreatectomy.

    Science.gov (United States)

    Traverso, L W; Abou-Zamzam, A M; Longmire, W P

    1981-01-01

    During total pancreaticoduodenectomy for chronic pancreatitis, four patients received an intraportal pancreatic mixed-cell autograft prepared by collagenase digestion. The technique of this autotransplantation procedure was successfully developed using a normal canine pancreas, but has proved difficult to apply in the human chronic pancreatitis model. Our four patients became insulin-dependent, with proof of intrahepatic insulin production in only one patient. Three factors have contributed to the lack of graft success: 1) the preoperative endocrine status, 2) systemic hypotension and portal hypertension secondary to graft infusion, and 3) difficulty applying the successful technique in a normal dog pancreas to an extensively scarred human pancreas. The preoperative insulin response during a glucose tolerance test was blunted or delayed in the three patients tested. An immediate decrease in blood pressure and rise in portal pressure occurred in every patient and prevented infusion of the entire graft (30-50%) in three patients. Unfortunately, the patient with the most compromised insulin status was the only patient able to receive the entire graft. Our experience would indicate that further refinements in technique are necessary to prevent the vascular reaction and allow infusion of the entire graft. Furthermore, normal islet cell function is necessary before a successful graft can be expected. PMID:6781424

  16. Sourcing human embryos for embryonic stem cell lines: Problems & perspectives

    OpenAIRE

    Mehta, Rajvi H.

    2014-01-01

    The ability to successfully derive human embryonic stem cells (hESC) lines from human embryos following in vitro fertilization (IVF) opened up a plethora of potential applications of this technique. These cell lines could have been successfully used to increase our understanding of human developmental biology, transplantation medicine and the emerging science of regenerative medicine. The main source for human embryos has been ′discarded′ or ′spare′ fresh or frozen human embryos following IVF...

  17. Efficient Induction and Isolation of Human Primordial Germ Cell-Like Cells from Competent Human Pluripotent Stem Cells.

    Science.gov (United States)

    Irie, Naoko; Surani, M Azim

    2017-01-01

    We recently reported a robust and defined culture system for the specification of human primordial germ cell-like cells (hPGCLCs) from human pluripotent stem cells (hPSCs), both embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) in vitro (Irie et al. Cell 160: 253-268, 2015). Similar attempts previously produced hPGCLCs from hPSCs at a very low efficiency, and the resulting cells were not fully characterized. A key step, which facilitated efficient hPGCLC specification from hPSCs, was the induction of a "competent" state for PGC fate via the medium containing a cocktail of four inhibitors. The competency of hPSCs can be maintained indefinitely and interchangeably with the conventional/low-competent hPSCs. Specification of hPGCLC occurs following sequential expression of key germ cell fate regulators, notably SOX17 and BLIMP1, as well as initiation of epigenetic resetting over 5 days. The hPGCLCs can be isolated using specific cell surface markers without the need for generating germ cell-specific reporter hPSC lines. This powerful method for the induction and isolation of hPGCLCs can be applied to both hESCs and iPSCs, which can be used for advances in human germ line biology.

  18. The similarity between human embryonic stem cell-derived epithelial cells and ameloblast-lineage cells

    Institute of Scientific and Technical Information of China (English)

    Li-Wei Zheng; Logan Linthicum; Pamela K DenBesten; Yan Zhang

    2013-01-01

    This study aimed to compare epithelial cells derived from human embryonic stem cells (hESCs) to human ameloblast-lineage cells (ALCs), as a way to determine their potential use as a cell source for ameloblast regeneration. Induced by various concentrations of bone morphogenetic protein 4 (BMP4), retinoic acid (RA) and lithium chloride (LiCI) for 7 days, hESCs adopted cobble-stone epithelial phenotype (hESC-derived epithelial cells (ES-ECs)) and expressed cytokeratin 14. Compared with ALCs and oral epithelial cells (OE), ES-ECs expressed amelogenesis-associated genes similar to ALCs. ES-ECs were compared with human fetal skin epithelium, human fetal oral buccal mucosal epithelial cells and human ALCs for their expression pattern of cytokeratins as well. ALCs had relatively high expression levels of cytokeratin 76, which ,vas also found to be upregulated in ES-ECs. Based on the present study, with the similarity of gene expression with ALCs, ES-ECs are a promising potential cell source for regeneration, which are not available in erupted human teeth for regeneration of enamel.

  19. Heptachlor induced mitochondria-mediated cell death via impairing electron transport chain complex III

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Seokheon; Kim, Joo Yeon; Hwang, Joohyun [Department of Molecular Biology, Sejong University, Seoul 143-747 (Korea, Republic of); Shin, Ki Soon [Department of Biology, Department of Life and Nanopharmaceutical Sciences, Kyung Hee University, Seoul 130-701 (Korea, Republic of); Kang, Shin Jung, E-mail: sjkang@sejong.ac.kr [Department of Molecular Biology, Sejong University, Seoul 143-747 (Korea, Republic of)

    2013-08-09

    Highlights: •Heptachlor inhibited mitochondrial electron transport chain complex III activity. •Heptachlor promoted generation of reactive oxygen species. •Heptachlor induced Bax activation. •Heptachlor induced mitochondria-mediated and caspase-dependent apoptosis. -- Abstract: Environmental toxins like pesticides have been implicated in the pathogenesis of Parkinson’s disease (PD). Epidemiological studies suggested that exposures to organochlorine pesticides have an association with an increased PD risk. In the present study, we examined the mechanism of toxicity induced by an organochlorine pesticide heptachlor. In a human dopaminergic neuroblastoma SH-SY5Y cells, heptachlor induced both morphological and functional damages in mitochondria. Interestingly, the compound inhibited mitochondrial electron transport chain complex III activity. Rapid generation of reactive oxygen species and the activation of Bax were then detected. Subsequently, mitochondria-mediated, caspase-dependent apoptosis followed. Our results raise a possibility that an organochlorine pesticide heptachlor can act as a neurotoxicant associated with PD.

  20. Radiosensitivity of Human Melanoma Cell Lines

    Energy Technology Data Exchange (ETDEWEB)

    Bergoc, R. M.; Medina, V.; Cricco, G.; Mohamed, N.; Martin, G.; Nunez, M.; Croci, M.; Crescenti, E. J.; Rivera, E. S.

    2004-07-01

    Cutaneous melanoma is a skin cancer resulting from the malign transformation of skin-pigment cells, the melanocytes. The radiotherapy, alone or in combination with other treatment, is an important therapy for this disease. the objective of this paper was to determine in vitro the radiosensitivity of two human melanoma cell lines with different metastatic capability: WM35 and MI/15, and to study the effect of drugs on radiobiological parameters. The Survival Curves were adjusted to the mathematical Linear-quadratic model using GrapsPad Prism software. Cells were seeded in RPMI medium (3000-3500 cells/flask), in triplicate and irradiated 24 h later. The irradiation was performed using an IBL 437C H Type equipment (189 TBq, 7.7 Gy/min) calibrated with a TLD 700 dosimeter. The range of Doses covered from 0 to 10 Gy and the colonies formed were counted at day 7th post-irradiation. Results obtained were: for WM35, {alpha}=0.37{+-}0.07 Gy''-1 and {beta}=0.06{+-}0.02 Gy''-2, for M1/15m {alpha}=0.47{+-}0.03 Gy''-1 and {beta}=0.06{+-}0.01 Gy''-2. The {alpha}/{beta} values WM35: {alpha}/{beta} values WM35: {alpha}/{beta}=6.07 Gy and M1/15: {alpha}/{beta}{sub 7}.33 Gy were similar, independently of their metastatic capabillity and indicate that both lines exhibit high radioresistance. Microscopic observation of irradiated cells showed multinuclear cells with few morphologic changes non-compatible with apoptosis. By means of specific fluorescent dyes and flow cytometry analysis we determined the intracellular levels of the radicals superoxide and hydrogen peroxide and their modulation in response to ionizing radiation. The results showed a marked decreased in H{sub 2}O{sub 2} intracellular levels with a simultaneous increase in superoxide that will be part of a mechanism responsible for induction of cell radioresistance. This response triggered by irradiated cells could not be abrogated by different treatments like histamine or the

  1. Modelling microbial fuel cells with suspended cells and added electron transfer mediator

    NARCIS (Netherlands)

    Picoreanu, C.; Katuri, K.P.; Van Loosdrecht, M.C.M.; Head, I.M.; Scott, K.

    2009-01-01

    Derivation of a mathematical model for microbial fuel cells (MFC) with suspended biomass and added electron-transfer mediator is described. The model is based on mass balances for several dissolved chemical species such as substrate, oxidized mediator and reduced mediator. Biological, chemical and e

  2. A holder assembly for cooperating with an environmental cell and an electron microscope

    NARCIS (Netherlands)

    Zandbergen, H.W.; Pleun, D.; Van Veen, G.N.A.

    2013-01-01

    The invention relates to a holder assembly for cooperating with an environmental cell ( 101 ) and an electron microscope, the environmental cell showing a fluid inlet (103), the electron microscope showing a vacuum wall (110) for separating an evacuable part of the electron microscope from the

  3. A holder assembly for cooperating with an environmental cell and an electron microscope

    NARCIS (Netherlands)

    Zandbergen, H.W.; Pleun, D.; Van Veen, G.N.A.

    2013-01-01

    The invention relates to a holder assembly for cooperating with an environmental cell ( 101 ) and an electron microscope, the environmental cell showing a fluid inlet (103), the electron microscope showing a vacuum wall (110) for separating an evacuable part of the electron microscope from the outsi

  4. Modeling of electron-electron collisions for particle-in-cell simulations

    Energy Technology Data Exchange (ETDEWEB)

    Andrea, D. d' ; Munz, C.D.; Schneider, R.

    2006-09-15

    The modeling of the physics of pulsed plasma thrusters requires the numerical solution of the Boltzmann equation for rarefied plasma flows where continuum assumptions fail. To tackle this challenging task, a cooperation between several institutes has been formed with the goal to develop a hybrid code based on Particle-In-Cell and Direct Simulation Monte Carlo techniques. These development activities are bundled in the project ''Numerische Simulation und Auslegung eines instationaeren gepulsten magnetoplasmadynamischen Triebwerks fuer eine Mondsonde'' which is funded by the Landesstiftung Baden-Wuerttemberg within the subject area ''Modellierung und Simulation auf Hochleistungscomputern''. In the frame of this project, the IHM is in charge to develop suitable physical-mathematical and numerical models to include charged particle collisions into the simulation. which can significantly affect the Parameters of such plasma devices. The intention of the present report is to introduce the Fokker-Planck approach for electron-electron interaction in Standard charged particle simulations. where the impact Parameter is usually large resulting in a small deflection angle. The theoretical and applicative framework is discussed in detail paying particular attention to the Particle-In-Cell approach in velocity space. a new technique which allows the self-consistent computation of the friction and diffusion coefficients arising from the Fokker-Planck treatment of collisions. These velocity-dependent coefficients thernselves are responsible for the change in velocity of the simulation particles, which is determined by the numerical solution of a Langevin-type equation. Simulation results for typical numerical experiments computed with the new developed Fokker-Planck solver are presented. demonstrating the quality. property and reliability of the applied numerical methods. (orig.)

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

    Science.gov (United States)

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

    2008-02-26

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

  6. Attachment of human primary osteoblast cells to modified polyethylene surfaces.

    Science.gov (United States)

    Poulsson, Alexandra H C; Mitchell, Stephen A; Davidson, Marcus R; Johnstone, Alan J; Emmison, Neil; Bradley, Robert H

    2009-04-09

    Ultra-high-molecular-weight polyethylene (UHMWPE) has a long history of use in medical devices, primarily for articulating surfaces due to its inherent low surface energy which limits tissue integration. To widen the applications of UHMWPE, the surface energy can be increased. The increase in surface energy would improve the adsorption of proteins and attachment of cells to allow tissue integration, thereby allowing UHMWPE to potentially be used for a wider range of implants. The attachment and function of human primary osteoblast-like (HOB) cells to surfaces of UHMWPE with various levels of incorporated surface oxygen have been investigated. The surface modification of the UHMWPE was produced by exposure to a UV/ozone treatment. The resulting surface chemistry was studied using X-ray photoelectron spectroscopy (XPS), and the topography and surface structure were probed by atomic force microscopy (AFM) and scanning electron microscopy (SEM), which showed an increase in surface oxygen from 11 to 26 atom % with no significant change to the surface topography. The absolute root mean square roughness of both untreated and UV/ozone-treated surfaces was within 350-450 nm, and the water contact angles decreased with increasing oxygen incorporation, i.e., showing an increase in surface hydrophilicity. Cell attachment and functionality were assessed over a 21 day period for each cell-surface combination studied; these were performed using SEM and the alamarBlue assay to study cell attachment and proliferation and energy-dispersive X-ray (EDX) analysis to confirm extracellular mineral deposits, and total protein assay to examine the intra- and extracellular protein expressed by the cells. HOB cells cultured for 21 days on the modified UHMWPE surfaces with 19 and 26 atom % oxygen incorporated showed significantly higher cell densities compared to cells cultured on tissue culture polystyrene (TCPS) from day 3 onward. This indicated that the cells attached and proliferated more

  7. Use of scanning electron microscopy to monitor nanofibre/cell interaction in digestive epithelial cells

    Energy Technology Data Exchange (ETDEWEB)

    Millaku, Agron, E-mail: agron.mi@hotmail.com [Limnos-Company for Applied Ecology Ltd, Podlimbarskega 31, 1000 Ljubljana (Slovenia); Drobne, Damjana [University of Ljubljana, Biotechnical Faculty, Department of Biology, Večna pot 111, 1000 Ljubljana (Slovenia); Centre of Excellence, Advanced Materials and Technologies for the Future (CO NAMASTE), Jamova cesta 39, 1000 Ljubljana (Slovenia); Centre of Excellence, Nanoscience and Nanotechnology (Nanocentre), Jamova cesta 39, 1000 Ljubljana (Slovenia); Torkar, Matjaz [Institute of Metals and Technology IMT, Lepi pot 11, 1000 Ljubljana (Slovenia); Jožef Stefan Institute, Condensed Matter Physics Department, Jamova cesta 39, 1000 Ljubljana (Slovenia); Novak, Sara [University of Ljubljana, Biotechnical Faculty, Department of Biology, Večna pot 111, 1000 Ljubljana (Slovenia); Remškar, Maja [Jožef Stefan Institute, Condensed Matter Physics Department, Jamova cesta 39, 1000 Ljubljana (Slovenia); Pipan-Tkalec, Živa [University of Ljubljana, Biotechnical Faculty, Department of Biology, Večna pot 111, 1000 Ljubljana (Slovenia)

    2013-09-15

    Graphical abstract: Scanning electron microscopy is particularly well suited to the observation of nanofibre/cell interaction in the endothelial cells lining the hepatopancreas. (a) Tungsten oxide nanofibres, (b) test organism Porcellio scaber and schematic appearance of digestive tubes, (c) digestive tube (hepatopancreas) prepared for SEM investigation, (d) digestive gland cells (C) with nanofibres (NF) embedded in the cell membrane and (e) nanofibres inserted deeply in the cells and damaged nanofibres due to peristalsis. -- Highlights: • Tungsten oxide nanofibres react physically with digestive gland epithelial cells in Porcellio scaber. • Physical peristaltic forces of lead to insertion of nanofibres into the cells. • No toxic responses as measured by conventional toxicity biomarkers were detected. • Physical interactions were observed in a majority of the investigated animals. -- Abstract: We provide data obtained by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) on the interaction of ingested tungsten nanofibers with epithelial cells of the digestive tubes of a test organism Porcellio scaber. Conventional toxicity endpoints including feeding behaviour, weight loss and mortality were also measured in each investigated animal. No toxicity was detected in any of exposed animals after 14 days of feeding on tungsten nanofiber dosed food, but when nanofibers enter the digestive system they can react with epithelial cells of the digestive tubes, becoming physically inserted into the cells. In this way, nanofibers can injure the epithelial cells of digestive gland tubes when they are ingested with food. Our SEM data suggest that peristaltic forces may have an important role, not predicted by in vitro experiments, in the interactions of nanomaterials with digestive intestinal cells.

  8. Adenovirus E1A/E1B Transformed Amniotic Fluid Cells Support Human Cytomegalovirus Replication

    Directory of Open Access Journals (Sweden)

    Natascha Krömmelbein

    2016-02-01

    Full Text Available The human cytomegalovirus (HCMV replicates to high titers in primary human fibroblast cell cultures. A variety of primary human cells and some tumor-derived cell lines do also support permissive HCMV replication, yet at low levels. Cell lines established by transfection of the transforming functions of adenoviruses have been notoriously resistant to HCMV replication and progeny production. Here, we provide first-time evidence that a permanent cell line immortalized by adenovirus type 5 E1A and E1B (CAP is supporting the full HCMV replication cycle and is releasing infectious progeny. The CAP cell line had previously been established from amniotic fluid cells which were likely derived from membranes of the developing fetus. These cells can be grown under serum-free conditions. HCMV efficiently penetrated CAP cells, expressed its immediate-early proteins and dispersed restrictive PML-bodies. Viral DNA replication was initiated and viral progeny became detectable by electron microscopy in CAP cells. Furthermore, infectious virus was released from CAP cells, yet to lower levels compared to fibroblasts. Subviral dense bodies were also secreted from CAP cells. The results show that E1A/E1B expression in transformed cells is not generally repressive to HCMV replication and that CAP cells may be a good substrate for dense body based vaccine production.

  9. Stereological quantification of mast cells in human synovium

    DEFF Research Database (Denmark)

    Damsgaard, T E; Sørensen, Flemming Brandt; Herlin, T;

    1999-01-01

    Mast cells participate in both the acute allergic reaction as well as in chronic inflammatory diseases. Earlier studies have revealed divergent results regarding the quantification of mast cells in the human synovium. The aim of the present study was therefore to quantify these cells in the human...... synovium, using stereological techniques. Different methods of staining and quantification have previously been used for mast cell quantification in human synovium. Stereological techniques provide precise and unbiased information on the number of cell profiles in two-dimensional tissue sections of......, in this case, human synovium. In 10 patients suffering from osteoarthritis a median of 3.6 mast cells/mm2 synovial membrane was found. The total number of cells (synoviocytes, fibroblasts, lymphocytes, leukocytes) present was 395.9 cells/mm2 (median). The mast cells constituted 0.8% of all the cell profiles...

  10. Technical Challenges in the Derivation of Human Pluripotent Cells

    Directory of Open Access Journals (Sweden)

    Parinya Noisa

    2011-01-01

    Full Text Available It has long been discovered that human pluripotent cells could be isolated from the blastocyst state of embryos and called human embryonic stem cells (ESCs. These cells can be adapted and propagated indefinitely in culture in an undifferentiated manner as well as differentiated into cell representing the three major germ layers: endoderm, mesoderm, and ectoderm. However, the derivation of human pluripotent cells from donated embryos is limited and restricted by ethical concerns. Therefore, various approaches have been explored and proved their success. Human pluripotent cells can also be derived experimentally by the nuclear reprogramming of somatic cells. These techniques include somatic cell nuclear transfer (SCNT, cell fusion and overexpression of pluripotent genes. In this paper, we discuss the technical challenges of these approaches for nuclear reprogramming, involving their advantages and limitations. We will also highlight the possible applications of these techniques in the study of stem cell biology.

  11. Human B cell activating factor (BCAF): production by a human T cell tumor line.

    Science.gov (United States)

    Fevrier, M; Diu, A; Mollier, P; Abadie, A; Olive, D; Mawas, C; Theze, J

    1989-01-01

    In a previous study, we demonstrated that supernatants from human T cell clones stimulated by a pair of anti-CD2 monoclonal antibodies cause resting human B cells to become activated and to proliferate in the absence of any other signals. The activity responsible for these effects was shown to be different from already characterized lymphokines and in particular from IL-2 and IL-4, and was named B Cell Activating Factor or BCAF. In this paper, we describe the production of BCAF by a human T cell tumor line T687 after phorbol myristate acetate (PMA) stimulation; this production can be potentiated by phytohemagglutinin (PHA). We further show that the stimulatory phase can be separated from the secretory phase thereby avoiding contamination of BCAF-containing supernatant by PMA and PHA. Supernatants produced under these conditions do not contain either IL-4 or IFN but contain traces of lymphotoxin and 2 to 10 ng/ml of IL-2. The T687 cell line will allow us to obtain a large volume of supernatant for biochemical study and purification of the molecule(s) responsible for BCAF activity.

  12. Transmission electron microscope cells for use with liquid samples

    Energy Technology Data Exchange (ETDEWEB)

    Khalid, Waqas; Alivisatos, Paul A.; Zettl, Alexander K.

    2016-08-09

    This disclosure provides systems, methods, and devices related to transmission electron microscopy cells for use with liquids. In one aspect a device includes a substrate, a first graphene layer, and a second graphene layer. The substrate has a first surface and a second surface. The first surface defines a first channel, a second channel, and an outlet channel. The first channel and the second channel are joined to the outlet channel. The outlet channel defines a viewport region forming a though hole in the substrate. The first graphene layer overlays the first surface of the substrate, including an interior area of the first channel, the second channel, and the outlet channel. The second graphene layer overlays the first surface of the substrate, including open regions defined by the first channel, the second channel, and the outlet channel.

  13. Trichloroethylene toxicity in a human hepatoma cell line

    Energy Technology Data Exchange (ETDEWEB)

    Thevenin, E.; McMillian, J. [Medical Univ. of Charleston South Carolina, SC (United States)

    1994-12-31

    The experiments conducted in this study were designed to determine the usefullness of hepatocyte cultures and a human hepatoma cell line as model systems for assessing human susceptibility to hepatocellular carcinoma due to exposure to trichloroethylene. The results from these studies will then be analyzed to determine if human cell lines can be used to conduct future experiments of this nature.

  14. Direct Reprogramming of Human Bone Marrow Stromal Cells into Functional Renal Cells Using Cell-free Extracts

    Science.gov (United States)

    Papadimou, Evangelia; Morigi, Marina; Iatropoulos, Paraskevas; Xinaris, Christodoulos; Tomasoni, Susanna; Benedetti, Valentina; Longaretti, Lorena; Rota, Cinzia; Todeschini, Marta; Rizzo, Paola; Introna, Martino; Grazia de Simoni, Maria; Remuzzi, Giuseppe; Goligorsky, Michael S.; Benigni, Ariela

    2015-01-01

    Summary The application of cell-based therapies in regenerative medicine is gaining recognition. Here, we show that human bone marrow stromal cells (BMSCs), also known as bone-marrow-derived mesenchymal cells, can be reprogrammed into renal proximal tubular-like epithelial cells using cell-free extracts. Streptolysin-O-permeabilized BMSCs exposed to HK2-cell extracts underwent morphological changes—formation of “domes” and tubule-like structures—and acquired epithelial functional properties such as transepithelial-resistance, albumin-binding, and uptake and specific markers E-cadherin and aquaporin-1. Transmission electron microscopy revealed the presence of brush border microvilli and tight intercellular contacts. RNA sequencing showed tubular epithelial transcript abundance and revealed the upregulation of components of the EGFR pathway. Reprogrammed BMSCs integrated into self-forming kidney tissue and formed tubular structures. Reprogrammed BMSCs infused in immunodeficient mice with cisplatin-induced acute kidney injury engrafted into proximal tubuli, reduced renal injury and improved function. Thus, reprogrammed BMSCs are a promising cell resource for future cell therapy. PMID:25754206

  15. Direct Reprogramming of Human Bone Marrow Stromal Cells into Functional Renal Cells Using Cell-free Extracts

    Directory of Open Access Journals (Sweden)

    Evangelia Papadimou

    2015-04-01

    Full Text Available The application of cell-based therapies in regenerative medicine is gaining recognition. Here, we show that human bone marrow stromal cells (BMSCs, also known as bone-marrow-derived mesenchymal cells, can be reprogrammed into renal proximal tubular-like epithelial cells using cell-free extracts. Streptolysin-O-permeabilized BMSCs exposed to HK2-cell extracts underwent morphological changes—formation of “domes” and tubule-like structures—and acquired epithelial functional properties such as transepithelial-resistance, albumin-binding, and uptake and specific markers E-cadherin and aquaporin-1. Transmission electron microscopy revealed the presence of brush border microvilli and tight intercellular contacts. RNA sequencing showed tubular epithelial transcript abundance and revealed the upregulation of components of the EGFR pathway. Reprogrammed BMSCs integrated into self-forming kidney tissue and formed tubular structures. Reprogrammed BMSCs infused in immunodeficient mice with cisplatin-induced acute kidney injury engrafted into proximal tubuli, reduced renal injury and improved function. Thus, reprogrammed BMSCs are a promising cell resource for future cell therapy.

  16. Human factors research problems in electronic voice warning system design

    Science.gov (United States)

    Simpson, C. A.; Williams, D. H.

    1975-01-01

    The speech messages issued by voice warning systems must be carefully designed in accordance with general principles of human decision making processes, human speech comprehension, and the conditions in which the warnings can occur. The operator's effectiveness must not be degraded by messages that are either inappropriate or difficult to comprehend. Important experimental variables include message content, linguistic redundancy, signal/noise ratio, interference with concurrent tasks, and listener expectations generated by the pragmatic or real world context in which the messages are presented.

  17. Modification of Isolation and Culture of Human Retinal Pigment Epithelial Cells

    Institute of Scientific and Technical Information of China (English)

    ZhengJL; GuoY

    1999-01-01

    Purpose:To modify the isolation of human retinal pigment pithelial(RPE)cells and to increase the purification and production of cultured RPE cells.Methods:The human eyecups were fixed on a fubber holder.After digestion by trypsin,RPE cells were collected,then cultured and identified by morphology,immunohistochemistry and electron microscopy.Results:The cultured RPE cells grew actively in the early stage with transparent nucleus and abundant melanin particles in cytoplasm.These cells were positive in DOPA oxidase reaction and in anti-pancytokeratin antibody staining.Cellular microvilli and tight junctions could be seen through transmission electrom microscopy.Conclusion:We developed a rubber holder to fix the eyecup.Using this holder,more and purer cultured RPE cells can be obtained.These cultured REP cells are similar to those in vivo in morphology and immunohistochemical staining.

  18. Human Immunodeficiency Syndromes Affecting Human Natural Killer Cell Cytolytic Activity

    OpenAIRE

    Ham, Hyoungjun; Billadeau, Daniel D.

    2014-01-01

    Natural killer (NK) cells are lymphocytes of the innate immune system that secrete cytokines upon activation and mediate the killing of tumor cells and virus-infected cells, especially those that escape the adaptive T cell response caused by the down regulation of MHC-I. The induction of cytotoxicity requires that NK cells contact target cells through adhesion receptors, and initiate activation signaling leading to increased adhesion and accumulation of F-actin at the NK cell cytotoxic synaps...

  19. Human immunodeficiency virus type 1 infection of human uterine epithelial cells: viral shedding and cell contact-mediated infectivity.

    Science.gov (United States)

    Asin, Susana N; Wildt-Perinic, Dunja; Mason, Sarah I; Howell, Alexandra L; Wira, Charles R; Fanger, Michael W

    2003-05-15

    We examined the mechanism of human immunodeficiency virus (HIV) type 1 infection of human uterine epithelial cells to gain a clearer understanding of the events by which HIV-1 infects cells within the female reproductive tract. We demonstrated that these cells can be productively infected by HIV-1 and that infection is associated with viral RNA reverse transcription, DNA transcription, and secretion of infectious virus. Levels of viral DNA and secreted virus decreased gradually after infection. Moreover, virus released by the uterine epithelial cells shortly after infection was able to infect human T cell lines, but virus released later did not. In contrast, human CD4(+) T cell lines were infected after cocultivation with epithelial cells at both early and late stages of infection. These data demonstrated that HIV-1 infects human epithelial cells of upper reproductive tract origin and that productive viral infection of epithelial cells may be an important mechanism of transmission of HIV-1 infection in women.

  20. Effect of human neural progenitor cells on injured spinal cord

    Institute of Scientific and Technical Information of China (English)

    XU Guang-hui; BAI Jin-zhu; CAI Qin-lin; LI Xiao-xia; LI Ling-song; SHEN Li

    2005-01-01

    Objective: To study whether human neural progenitor cells can differentiate into neural cells in vivo and improve the recovery of injured spinal cord in rats.Methods: Human neural progenitor cells were transplanted into the injured spinal cord and the functional recovery of the rats with spinal cord contusion injury was evaluated with Basso-Beattie-Bresnahan (BBB) locomotor scale and motor evoked potentials. Additionally, the differentiation of human neural progenitor cells was shown by immunocytochemistry.Results: Human neural progenitor cells developed into functional cells in the injured spinal cord and improved the recovery of injured spinal cord in both locomotor scores and electrophysiological parameters in rats.Conclusions: Human neural progenitor cells can treat injured spinal cord, which may provide a new cell source for research of clinical application.

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

    Science.gov (United States)

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

    2009-05-28

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

  2. A Chemical Probe that Labels Human Pluripotent Stem Cells

    Directory of Open Access Journals (Sweden)

    Nao Hirata

    2014-03-01

    Full Text Available A small-molecule fluorescent probe specific for human pluripotent stem cells would serve as a useful tool for basic cell biology research and stem cell therapy. Screening of fluorescent chemical libraries with human induced pluripotent stem cells (iPSCs and subsequent evaluation of hit molecules identified a fluorescent compound (Kyoto probe 1 [KP-1] that selectively labels human pluripotent stem cells. Our analyses indicated that the selectivity results primarily from a distinct expression pattern of ABC transporters in human pluripotent stem cells and from the transporter selectivity of KP-1. Expression of ABCB1 (MDR1 and ABCG2 (BCRP, both of which cause the efflux of KP-1, is repressed in human pluripotent stem cells. Although KP-1, like other pluripotent markers, is not absolutely specific for pluripotent stem cells, the identified chemical probe may be used in conjunction with other reagents.

  3. Evaluation of the bleached human enamel by Scanning Electron Microscopy

    DEFF Research Database (Denmark)

    Miranda, Carolina Baptista; Pagani, Clovis; Benetti, Ana Raquel

    2005-01-01

    Since bleaching has become a popular procedure, the effect of peroxides on dental hard tissues is of great interest in research. Purpose: The aim of this in vitro study was to perform a qualitative analysis of the human enamel after the application of in-office bleaching agents, using Scanning El...

  4. Enhanced casein kinase II activity in human tumour cell cultures

    DEFF Research Database (Denmark)

    Prowald, K; Fischer, H; Issinger, O G

    1984-01-01

    Casein kinase II (CKII) activity is enhanced as much as 2-3 fold in established and 4-5-fold in transformed human cell lines when compared to that of fibroblasts and primary human tumour cell cultures where CKII activity never exceeded a basic level. The high activity of CKII in transformed cells...

  5. MODERATE CYTOTOXICITY OF PROANTHOCYANIDINS TO HUMAN TUMOR-CELL LINES

    NARCIS (Netherlands)

    KOLODZIEJ, H; HABERLAND, C; WOERDENBAG, HJ; KONINGS, AWT

    1995-01-01

    In the present study the cytotoxicity of 16 proanthocyanidins was evaluated in GLC(4), a human small cell lung carcinoma cell line, and in COLO 320, a human colorectal cancer cell line, using the microculture tetrazolium (MTT) assay. With IC50 values ranging from 18 to >200 mu m following continuous

  6. Derivation and differentiation of haploid human embryonic stem cells.

    Science.gov (United States)

    Sagi, Ido; Chia, Gloryn; Golan-Lev, Tamar; Peretz, Mordecai; Weissbein, Uri; Sui, Lina; Sauer, Mark V; Yanuka, Ofra; Egli, Dieter; Benvenisty, Nissim

    2016-04-07

    Diploidy is a fundamental genetic feature in mammals, in which haploid cells normally arise only as post-meiotic germ cells that serve to ensure a diploid genome upon fertilization. Gamete manipulation has yielded haploid embryonic stem (ES) cells from several mammalian species, but haploid human ES cells have yet to be reported. Here we generated and analysed a collection of human parthenogenetic ES cell lines originating from haploid oocytes, leading to the successful isolation and maintenance of human ES cell lines with a normal haploid karyotype. Haploid human ES cells exhibited typical pluripotent stem cell characteristics, such as self-renewal capacity and a pluripotency-specific molecular signature. Moreover, we demonstrated the utility of these cells as a platform for loss-of-function genetic screening. Although haploid human ES cells resembled their diploid counterparts, they also displayed distinct properties including differential regulation of X chromosome inactivation and of genes involved in oxidative phosphorylation, alongside reduction in absolute gene expression levels and cell size. Surprisingly, we found that a haploid human genome is compatible not only with the undifferentiated pluripotent state, but also with differentiated somatic fates representing all three embryonic germ layers both in vitro and in vivo, despite a persistent dosage imbalance between the autosomes and X chromosome. We expect that haploid human ES cells will provide novel means for studying human functional genomics and development.

  7. Human embryonic stem cells and respect for life

    OpenAIRE

    Meyer, J.(CERN, Geneva, Switzerland)

    2000-01-01

    The purpose of this essay is to stimulate academic discussion about the ethical justification of using human primordial stem cells for tissue transplantation, cell replacement, and gene therapy. There are intriguing alternatives to using embryos obtained from elective abortions and in vitro fertilisation to reconstitute damaged or dysfunctional human organs. These include the expansion and transplantation of latent adult progenitor cells.

  8. Ultrastructural characteristics of novel epithelial cell types identified in human pathologic liver specimens with chronic ductular reaction.

    OpenAIRE

    De Vos, R; Desmet, V

    1992-01-01

    Previous immunohistochemical studies on human liver biopsies with chronic ductular reaction revealed the presence of "small cells" with bile-duct type cytokeratin profile in the periportal area. This study identified similar cells by electron microscopy. The authors studied 13 human liver specimens with various liver diseases, but all characterized by chronic ductular reaction. In all specimens, variable numbers of "small cells" with common epithelial characteristics were identified in the pe...

  9. Effect of antisense oligodeoxynucleotide targeting survivin on growth of human gastric cancer cells

    Directory of Open Access Journals (Sweden)

    Lantao Xu

    2013-03-01

    Full Text Available Our study investigated the effects of antisense oligodeoxynucleotide targeting survivin on human gastric cancer cells. Human gastric cancer cells were incubated with antisense oligodeoxynucleotide targeting survivin for pre-designed durations, and then the cell growth was observed under light and electronic microscopes. Electrophoresis of fractured DNA fragments was performed to detect the DNA distribution and telomere repeat amplification protocol (TRAP was used for the detection of telomerase activity. Antisense oligodeoxynucleotide targeting survivin could induce the apoptosis of human gastric cancer cells which were characterized by plasma membrane blistering, chromatin condensation, nuclear fragmentation, and formation of apoptotic bodies. Electrophoresis showed characteristic DNA ladder. Flow cytometry revealed hypo-diploid apoptosis peak before G1 phase and the telomerase activity was significantly inhibited. These results demonstrated antisense oligodeoxynucleotide targeting survivin can induce the apoptosis of gastric cancer cells to inhibit their proliferation.

  10. Abnormalities in human pluripotent cells due to reprogramming mechanisms.

    Science.gov (United States)

    Ma, Hong; Morey, Robert; O'Neil, Ryan C; He, Yupeng; Daughtry, Brittany; Schultz, Matthew D; Hariharan, Manoj; Nery, Joseph R; Castanon, Rosa; Sabatini, Karen; Thiagarajan, Rathi D; Tachibana, Masahito; Kang, Eunju; Tippner-Hedges, Rebecca; Ahmed, Riffat; Gutierrez, Nuria Marti; Van Dyken, Crystal; Polat, Alim; Sugawara, Atsushi; Sparman, Michelle; Gokhale, Sumita; Amato, Paula; Wolf, Don P; Ecker, Joseph R; Laurent, Louise C; Mitalipov, Shoukhrat

    2014-07-10

    Human pluripotent stem cells hold potential for regenerative medicine, but available cell types have significant limitations. Although embryonic stem cells (ES cells) from in vitro fertilized embryos (IVF ES cells) represent the 'gold standard', they are allogeneic to patients. Autologous induced pluripotent stem cells (iPS cells) are prone to epigenetic and transcriptional aberrations. To determine whether such abnormalities are intrinsic to somatic cell reprogramming or secondary to the reprogramming method, genetically matched sets of human IVF ES cells, iPS cells and nuclear transfer ES cells (NT ES cells) derived by somatic cell nuclear transfer (SCNT) were subjected to genome-wide analyses. Both NT ES cells and iPS cells derived from the same somatic cells contained comparable numbers of de novo copy number variations. In contrast, DNA methylation and transcriptome profiles of NT ES cells corresponded closely to those of IVF ES cells, whereas iPS cells differed and retained residual DNA methylation patterns typical of parental somatic cells. Thus, human somatic cells can be faithfully reprogrammed to pluripotency by SCNT and are therefore ideal for cell replacement therapies.

  11. Evaluating the performance of microbial fuel cells powering electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Dewan, Alim; Beyenal, Haluk [Gene and Linda Voiland School of Chemical Engineering and Bioengineering, Center for Environmental, Sediment and Aquatic Research, Pullman, WA (United States); Donovan, Conrad; Heo, Deukhyoun [School of Electrical Engineering and Computer Science, Washington State University, Pullman, WA 99163-2710 (United States)

    2010-01-01

    A microbial fuel cell (MFC) is capable of powering an electronic device if we store the energy in an external storage device, such as a capacitor, and dispense that energy intermittently in bursts of high-power when needed. Therefore its performance needs to be evaluated using an energy-storing device such as a capacitor which can be charged and discharged rather than other evaluation techniques, such as continuous energy dissipation through a resistor. In this study, we develop a method of testing microbial fuel cell performance based on storing energy in a capacitor. When a capacitor is connected to a MFC it acts like a variable resistor and stores energy from the MFC at a variable rate. In practice the application of this method to testing microbial fuel cells is very challenging and time consuming; therefore we have custom-designed a microbial fuel cell tester (MFCT). The MFCT evaluates the performance of a MFC as a power source. It uses a capacitor as an energy storing device and waits until a desired amount of energy is stored then discharges the capacitor. The entire process is controlled using an analog-to-digital converter (ADC) board controlled by a custom-written computer program. The utility of our method and the MFCT is demonstrated using a laboratory microbial fuel cell (LMFC) and a sediment microbial fuel cell (SMFC). We determine (1) how frequently a MFC can charge a capacitor, (2) which electrode is current-limiting, (3) what capacitor value will allow the maximum harvested energy from a MFC, which is called the ''optimum charging capacitor value,'' and (4) what capacitor charging potential will harvest the maximum energy from a MFC, which is called the ''optimum charging potential.'' Using a LMFC we find that (1) the time needed to charge a 3-F capacitor from 0 to 500 mV is 108 min, (2) the optimum charging capacitor value is 3 F, and (3) the optimum charging potential is 300 mV. Using a SMFC we find that (1

  12. Proteomic analysis of human blastocoel fluid and blastocyst cells

    DEFF Research Database (Denmark)

    Jensen, Pernille; Beck, Hans Christian; Petersen, Jørgen

    2013-01-01

    Human embryonic stem cells (hESCs) are derived from the inner cell mass (ICM) of the blastocyst and can differentiate into any cell type in the human body. These cells hold a great potential for regenerative medicine, but to obtain enough cells needed for medical treatment, culture is required......, the blastocoel fluid, which is in contact with all the cells in the blastocyst, including hESCs. Fifty-three surplus human blastocysts were donated after informed consent, and blastocoel fluid was isolated by micromanipulation. Using highly sensitive nano-high-pressure liquid chromatography-tandem mass...

  13. EXPRESSION OF Fas LIGAND IN HUMAN COLON CANCER CELL LINES

    Institute of Scientific and Technical Information of China (English)

    张建军; 丁尔迅; 王强; 陈学云; 付志仁

    2001-01-01

    To investigate the expression of Fas ligand in human colon carcinoma cell lines. Methods: A total of six human colon cancer cell lines were examined for the expression of Fas ligand mRNA and cell surface protein by using RT-PCR and flow cytometry respectively. Results: The results showed that Fas ligand mRNA was expressed in all of the six cancer cell lines and Fas ligand cell surface protein was expressed in part of them. Conclusion: These data suggest that Fas ligand was expressed, at least in part, in human colon cancer cell lines and might facilitate to escape from immune surveillance of the host.

  14. Dynamic behaviour of human neuroepithelial cells in the developing forebrain

    Science.gov (United States)

    Subramanian, Lakshmi; Bershteyn, Marina; Paredes, Mercedes F.; Kriegstein, Arnold R.

    2017-01-01

    To understand how diverse progenitor cells contribute to human neocortex development, we examined forebrain progenitor behaviour using timelapse imaging. Here we find that cell cycle dynamics of human neuroepithelial (NE) cells differ from radial glial (RG) cells in both primary tissue and in stem cell-derived organoids. NE cells undergoing proliferative, symmetric divisions retract their basal processes, and both daughter cells regrow a new process following cytokinesis. The mitotic retraction of the basal process is recapitulated by NE cells in cerebral organoids generated from human-induced pluripotent stem cells. In contrast, RG cells undergoing vertical cleavage retain their basal fibres throughout mitosis, both in primary tissue and in older organoids. Our findings highlight developmentally regulated changes in mitotic behaviour that may relate to the role of RG cells to provide a stable scaffold for neuronal migration, and suggest that the transition in mitotic dynamics can be studied in organoid models. PMID:28139695

  15. Caveolin-1 associated adenovirus entry into human corneal cells.

    Directory of Open Access Journals (Sweden)

    Mohammad A Yousuf

    Full Text Available The cellular entry of viruses represents a critical area of study, not only for viral tropism, but also because viral entry dictates the nature of the immune response elicited upon infection. Epidemic keratoconjunctivitis (EKC, caused by viruses within human adenovirus species D (HAdV-D, is a severe, ocular surface infection associated with corneal inflammation. Clathrin-mediated endocytosis has previously been shown to play a critical role in entry of other HAdV species into many host cell types. However, HAdV-D endocytosis into corneal cells has not been extensively studied. Herein, we show an essential role for cholesterol rich, lipid raft microdomains and caveolin-1, in the entry of HAdV-D37 into primary human corneal fibroblasts. Cholesterol depletion using methyl-β-cyclodextrin (MβCD profoundly reduced viral infection. When replenished with soluble cholesterol, the effect of MβCD was reversed, allowing productive viral infection. HAdV-D37 DNA was identified in caveolin-1 rich endosomal fractions after infection. Src kinase activity was also increased in caveolin-1 rich endosomal fractions after infection, and Src phosphorylation and CXCL1 induction were both decreased in caveolin-1-/- mice corneas compared to wild type mice. siRNA knock down of caveolin-1 in corneal cells reduced chemokine induction upon viral infection, and caveolin-1-/- mouse corneas showed reduced cellular entry of HAdV-D37. As a control, HAdV-C2, a non-corneal pathogen, appeared to utilize the caveolar pathway for entry into A549 cells, but failed to infect corneal cells entirely, indicating virus and cell specific tropism. Immuno-electron microscopy confirmed the presence of caveolin-1 in HAdV-D37-containing vesicles during the earliest stages of viral entry. Collectively, these experiments indicate for the first time that HAdV-D37 uses a lipid raft mediated caveolin-1 associated pathway for entry into corneal cells, and connects the processes of viral entry with

  16. Kalkitoxin Inhibits Angiogenesis, Disrupts Cellular Hypoxic Signaling, and Blocks Mitochondrial Electron Transport in Tumor Cells

    Directory of Open Access Journals (Sweden)

    J. Brian Morgan

    2015-03-01

    Full Text Available The biologically active lipopeptide kalkitoxin was previously isolated from the marine cyanobacterium Moorea producens (Lyngbya majuscula. Kalkitoxin exhibited N-methyl-d-aspartate (NMDA-mediated neurotoxicity and acted as an inhibitory ligand for voltage-sensitive sodium channels in cultured rat cerebellar granule neurons. Subsequent studies revealed that kalkitoxin generated a delayed form of colon tumor cell cytotoxicity in 7-day clonogenic cell survival assays. Cell line- and exposure time-dependent cytostatic/cytotoxic effects were previously observed with mitochondria-targeted inhibitors of hypoxia-inducible factor-1 (HIF-1. The transcription factor HIF-1 functions as a key regulator of oxygen homeostasis. Therefore, we investigated the ability of kalkitoxin to inhibit hypoxic signaling in human tumor cell lines. Kalkitoxin potently and selectively inhibited hypoxia-induced activation of HIF-1 in T47D breast tumor cells (IC50 5.6 nM. Mechanistic studies revealed that kalkitoxin inhibits HIF-1 activation by suppressing mitochondrial oxygen consumption at electron transport chain (ETC complex I (NADH-ubiquinone oxidoreductase. Further studies indicate that kalkitoxin targets tumor angiogenesis by blocking the induction of angiogenic factors (i.e., VEGF in tumor cells.

  17. Use of scanning electron microscopy to monitor nanofibre/cell interaction in digestive epithelial cells.

    Science.gov (United States)

    Millaku, Agron; Drobne, Damjana; Torkar, Matjaz; Novak, Sara; Remškar, Maja; Pipan-Tkalec, Živa

    2013-09-15

    We provide data obtained by scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) on the interaction of ingested tungsten nanofibers with epithelial cells of the digestive tubes of a test organism Porcellio scaber. Conventional toxicity endpoints including feeding behaviour, weight loss and mortality were also measured in each investigated animal. No toxicity was detected in any of exposed animals after 14 days of feeding on tungsten nanofiber dosed food, but when nanofibers enter the digestive system they can react with epithelial cells of the digestive tubes, becoming physically inserted into the cells. In this way, nanofibers can injure the epithelial cells of digestive gland tubes when they are ingested with food. Our SEM data suggest that peristaltic forces may have an important role, not predicted by in vitro experiments, in the interactions of nanomaterials with digestive intestinal cells.

  18. Phenotypes and karyotypes of human malignant mesothelioma cell lines.

    Directory of Open Access Journals (Sweden)

    Vandana Relan

    Full Text Available BACKGROUND: Malignant mesothelioma is an aggressive tumour of serosal surfaces most commonly pleura. Characterised cell lines represent a valuable tool to study the biology of mesothelioma. The aim of this study was to develop and biologically characterise six malignant mesothelioma cell lines to evaluate their potential as models of human malignant mesothelioma. METHODS: Five lines were initiated from pleural biopsies, and one from pleural effusion of patients with histologically proven malignant mesothelioma. Mesothelial origin was assessed by standard morphology, Transmission Electron Microscopy (TEM and immunocytochemistry. Growth characteristics were assayed using population doubling times. Spectral karyotyping was performed to assess chromosomal abnormalities. Authentication of donor specific derivation was undertaken by DNA fingerprinting using a panel of SNPs. RESULTS: Most of cell lines exhibited spindle cell shape, with some retaining stellate shapes. At passage 2 to 6 all lines stained positively for calretinin and cytokeratin 19, and demonstrated capacity for anchorage-independent growth. At passage 4 to 16, doubling times ranged from 30-72 hours, and on spectral karyotyping all lines exhibited numerical chromosomal abnormalities ranging from 41 to 113. Monosomy of chromosomes 8, 14, 22 or 17 was observed in three lines. One line displayed four different karyotypes at passage 8, but only one karyotype at passage 42, and another displayed polyploidy at passage 40 which was not present at early passages. At passages 5-17, TEM showed characteristic features of mesothelioma ultrastructure in all lines including microvilli and tight intercellular junctions. CONCLUSION: These six cell lines exhibit varying cell morphology, a range of doubling times, and show diverse passage-dependent structural chromosomal changes observed in malignant tumours. However they retain characteristic immunocytochemical protein expression profiles of

  19. Prevention of electron beam transmittance for biological cell imaging using electron beam excitation-assisted optical microscope

    Science.gov (United States)

    Fukuta, Masahiro; Nawa, Yasunori; Inami, Wataru; Kawata, Yoshimasa

    2017-04-01

    We demonstrated the high-spatial-resolution imaging of label-free biological cells using an electron beam excitation-assisted optical (EXA) microscope without irradiation damage by the electron beam. An EXA microscope can be used to observe a specimen with a nanometric light source excited in the Si3N4 membrane by an electron beam. The incident electron beam penetrates the Si3N4 membrane and damages the specimen. To suppress the irradiation damage of the specimen, we prevented the transmittance of the electron beam by coating the Si3N4 membrane with a gold thin film. To obtain an electron beam transmittance through the Si3N4 of 0%, a gold film of 15 nm thickness was required. By adding the gold layer, a label-free cellular structure was observed with 135-nm spatial resolution.

  20. Discovery of a new RNA-containing nuclear structure in UVC-induced apoptotic cells by integrated laser electron microscopy.

    Science.gov (United States)

    Karreman, Matthia A; Agronskaia, Alexandra V; Verkleij, Arie J; Cremers, Fons F M; Gerritsen, Hans C; Humbel, Bruno M

    2009-05-01

    Treatment of cells with UVC radiation leads to the formation of DNA cross-links which, if not repaired, can lead to apoptosis. gamma-H2AX and cleaved caspase 3 are proteins formed during UVC-induced DNA damage and apoptosis respectively. The present study sets out to identify early morphological markers of apoptosis using a new method of correlative microscopy, ILEM (integrated laser electron microscopy). Cleaved caspase 3 and gamma-H2AX were immunofluorescently labelled to mark the cells of interest. These cells were subsequently searched in the fluorescence mode of the ILEM and further analysed at high resolution with TEM (transmission electron microscopy). Following the treatment of HUVECs (human umbilical vein endothelial cells) with UVC radiation, in the majority of the cells gamma-H2AX was formed, whereas only in a subset of cells caspase 3 was activated. In severely damaged cells with high levels of gamma-H2AX a round, electron-dense nuclear structure was found, which was hitherto not identified in UV-stressed cells. This structure exists only in nuclei of cells containing cleaved caspase 3 and is present during all stages of the apoptotic process. Energy-loss imaging showed that the nuclear structure accumulates phosphorus, indicating that it is rich in nucleic acids. Because the nuclear structure did not label for DNA and was not affected by regressive EDTA treatment, it is suggested that the UV-induced nuclear structure contains a high amount of RNA. Because the UV-induced nuclear structure was only found in cells labelled for cleaved caspase 3 it is proposed as an electron microscopic marker for all stages of apoptosis. Such a marker will especially facilitate the screening for early apoptotic cells, which lack the well-known hallmarks of apoptosis within a cell population. It also raises new questions on the mechanisms involved in the UV-induced apoptotic pathway.

  1. Derivation of a Homozygous Human Androgenetic Embryonic Stem Cell Line.

    Science.gov (United States)

    Ding, Chenhui; Huang, Sunxing; Qi, Quan; Fu, Rui; Zhu, Wanwan; Cai, Bing; Hong, Pingping; Liu, Zhengxin; Gu, Tiantian; Zeng, Yanhong; Wang, Jing; Xu, Yanwen; Zhao, Xiaoyang; Zhou, Qi; Zhou, Canquan

    2015-10-01

    Human embryonic stem cells (hESCs) have long been considered as a promising source for cell replacement therapy. However, one major obstacle for the use of these cells is immune compatibility. Histocompatible human parthenogenetic ESCs have been reported as a new method for generating human leukocyte antigen (HLA)-matched hESCs. To further investigate the possibility of obtaining histocompatible stem cells from uniparental embryos, we tried to produce androgenetic haploid human embryos by injecting a single spermatozoon into enucleated human oocyte, and establish human androgenetic embryonic stem (hAGES) cell lines from androgenetic embryos. In the present study, a diploid hAGES cell line has been established, which exhibits typical features of human ESCs, including the expression of pluripotency markers, having differentiation potential in vitro and in vivo, and stable propagation in an undifferentiated state (>P40). Bisulfite sequencing of the H19, Snrpn, Meg3, and Kv imprinting control regions suggested that hAGES cells maintained to a certain extent a sperm methylation pattern. Genome-wide single nucleotide polymorphism, short tandem repeat, and HLA analyses revealed that the hAGES cell genome was highly homozygous. These results suggest that hAGES cells from spermatozoon could serve as a useful tool for studying the mechanisms underlying genomic imprinting in humans. It might also be used as a potential resource for cell replacement therapy as parthenogenetic stem cells.

  2. Human Cell and Tissue Establishment Registration Public Query

    Data.gov (United States)

    U.S. Department of Health & Human Services — This application provides Human Cell and Tissue registration information for registered, inactive, and pre-registered firms. Query options are by Establishment Name,...

  3. Human Cell and Tissue Establishment Registration Public Query

    Data.gov (United States)

    U.S. Department of Health & Human Services — This application provides Human Cell and Tissue registration information for registered, inactive, and pre-registered firms. Query options are by Establishment Name,...

  4. Human tissue legislation in South Africa: Focus on stem cell ...

    African Journals Online (AJOL)

    Human tissue legislation in South Africa: Focus on stem cell research and therapy. ... Related Substances Act, the Consumer Protection Act, the Children's Act and ... human tissue legislation in SA, the legislator has an opportunity to mirror the ...

  5. Human Stem Cell Derived Cardiomyocytes: An Alternative ...

    Science.gov (United States)

    Chemical spills and associated deaths in the US has increased 2.6-fold and 16-fold from 1983 to 2012, respectfully. In addition, the number of chemicals to which humans are exposed to in the environment has increased almost 10-fold from 2001 to 2013 within the US. Internationally, a WHO report on the global composite impact of chemicals on health reported that 16% of the total burden of cardiovascular disease was attributed to environmental chemical exposure with 2.5 million deaths per year. Clearly, the cardiovascular system, at all its various developmental and life stages, represents a critical target organ system that can be adversely affected by existing and emerging chemicals (e.g., engineered nanomaterials) in a variety of environmental media. The ability to assess chemical cardiac risk and safety is critically needed but extremely challenging due to the number and categories of chemicals in commerce, as indicated. This presentation\\session will evaluate the use of adult human stem cell derived cardiomyocytes, and existing platforms, as an alternative model to evaluate environmental chemical cardiac toxicity as well as provide key information for the development of predictive adverse outcomes pathways associated with environmental chemical exposures. (This abstract does not represent EPA policy) Rapid and translatable chemical safety screening models for cardiotoxicity current status for informing regulatory decisions, a workshop sponsored by the Society

  6. Human pancreatic β-cell G1/S molecule cell cycle atlas.

    Science.gov (United States)

    Fiaschi-Taesch, Nathalie M; Kleinberger, Jeffrey W; Salim, Fatimah G; Troxell, Ronnie; Wills, Rachel; Tanwir, Mansoor; Casinelli, Gabriella; Cox, Amy E; Takane, Karen K; Scott, Donald K; Stewart, Andrew F

    2013-07-01

    Expansion of pancreatic β-cells is a key goal of diabetes research, yet induction of adult human β-cell replication has proven frustratingly difficult. In part, this reflects a lack of understanding of cell cycle control in the human β-cell. Here, we provide a comprehensive immunocytochemical "atlas" of G1/S control molecules in the human β-cell. This atlas reveals that the majority of these molecules, previously known to be present in islets, are actually present in the β-cell. More importantly, and in contrast to anticipated results, the human β-cell G1/S atlas reveals that almost all of the critical G1/S cell cycle control molecules are located in the cytoplasm of the quiescent human β-cell. Indeed, the only nuclear G1/S molecules are the cell cycle inhibitors, pRb, p57, and variably, p21: none of the cyclins or cdks necessary to drive human β-cell proliferation are present in the nuclear compartment. This observation may provide an explanation for the refractoriness of human β-cells to proliferation. Thus, in addition to known obstacles to human β-cell proliferation, restriction of G1/S molecules to the cytoplasm of the human β-cell represents an unanticipated obstacle to therapeutic human β-cell expansion.

  7. Identification of molecules derived from human fibroblast feeder cells that support the proliferation of human embryonic stem cells

    DEFF Research Database (Denmark)

    Anisimov, Sergey V.; Christophersen, Nicolaj S.; Correia, Ana S.

    2011-01-01

    the proliferation and pluripotency of these cells. Importantly, feeder cells generally lose their capacity to support human embryonic stem cell proliferation in vitro following long-term culture. In this study, we performed large-scale gene expression profiles of human foreskin fibroblasts during early...

  8. Human embryonic stem cell research: ethical and legal issues.

    Science.gov (United States)

    Robertson, J A

    2001-01-01

    The use of human embryonic stem cells to replace damaged cells and tissues promises future hope for the treatment of many diseases. However, many countries now face complex ethical and legal questions as a result of the research needed to develop these cell-replacement therapies. The challenge that must be met is how to permit research on human embryonic tissue to occur while maintaining respect for human life generally.

  9. Bio-synthesis of gold nanoparticles by human epithelial cells, in vivo

    Energy Technology Data Exchange (ETDEWEB)

    Larios-Rodriguez, E; Rangel-Ayon, C; Herrera-Urbina, R [Departamento de Ingenieria Quimica y Metalurgia, Universidad de Sonora, Rosales y Luis Encinas S/N, Hermosillo, Sonora, C.P. 83000 (Mexico); Castillo, S J [Departamento de Investigacion en Fisica, Universidad de Sonora, Rosales y Luis Encinas S/N, Hermosillo, Sonora, C.P. 83000 (Mexico); Zavala, G, E-mail: elarios@polimeros.uson.mx [Instituto de Biotecnologia, Universidad Nacional Autonoma de Mexico, Cuernavaca, Morelos (Mexico)

    2011-09-02

    Healthy epithelial cells, in vivo, have the ability to synthesize gold nanoparticles when aqueous tetrachloroauric acid is made to react with human skin. Neither a reducing agent nor a protecting chemical is needed for this bio-synthesis method. The first indication of gold nanoparticle formation is the staining of the skin, which turns deep purple. Stereoscopic optical micrographs of human skin tissue in contact with aqueous tetrachloroauric acid clearly show the staining of the epithelial cells. The UV-Vis spectrum of these epithelial cells shows an absorption band with a maximum at 553 nm. This absorption peak is within the wavelength region where the surface plasmon resonance (SPR) band of aqueous colloidal gold exhibits a maximum. Transmission electron micrographs show that gold nanoparticles synthesized by epithelial cells have sizes between 1 and 100 nm. The electron diffraction pattern of these nanoparticles reveals a crystalline structure whose interplanar distances correspond to fcc metallic gold. Transmission electron micrographs of ultra-thin (70 nm thick) slices of epithelial cells clearly and undoubtedly demonstrate that gold nanoparticles are inside the cell. According to high resolution transmission electron micrographs of intracellular single gold nanoparticles, they have the shape of a polyhedron.

  10. Epigenetic Regulation of Human Embryonic Stem Cells

    Directory of Open Access Journals (Sweden)

    Qidong eHu

    2012-11-01

    Full Text Available Recently, there has been tremendous progress in characterizing the transcriptional network regulating hESCs (MacArthur et al., 2009; Loh et al., 2011, including those signaling events mediated by Oct4, Nanog and Sox2. There is growing interest in the epigenetic machinery involved in hESC self-renewal and differentiation. In general, epigenetic regulation includeschromatin reorganization, DNA modification and histone modification, which are not directly related to alterations in DNA sequences. Various protein complexes, includingPolycomb, trithorax, NuRD, SWI/SNF andOct4, have been shown to play critical roles in epigenetic control of hESC maintenance and differentiation. Hence, we will formally review recent advances in unraveling the multifaceted role of epigenetic regulation in hESC self-renewal and induced differentiation, particularly with respect to chromatin remodeling and DNA methylation events. Unraveling the molecular mechanisms underlying the maintenance/differentiation of hESCs and reprogramming of somatic cells will greatly strengthen our capacity to generate various types of cells to treat human diseases.

  11. Mast cells and human hepatocellular carcinoma

    Institute of Scientific and Technical Information of China (English)

    Fabio Grizzi; Barbara Franceschini; Maurizio Chiriva-Internati; Young Liu; Paul L. Hermonat; Nicola Dioguardi

    2003-01-01

    AIM: To investigate the density of mast cells (MCs) in human hepatocellular carcinoma (HCC), and to determine whether the MCs density has any correlations with histopathological grading, staging or some baseline patient characteristics.METHODS: Tissue sections of 22 primary HCCs were histochemically stained with toluidine blue, in order to be able to quantify the MCs in and around the neoplasm using a computer-assisted image analysis system. HCC was staged and graded by two independent pathologists. To identify the sinusoidal capillarisation of each specimen 3μm thick sections were histochemically stained with sirius red, and semi-quantitatively evaluated by two independent observers. The data were statistically analysed using Spearman′s correlation and Student′s t-test when appropriate.RESULTS: MCs density did not correlate with the age or sex of the patients, the serum alanine aminotransferase (ALT) or aspartate aminotransferase (AST) levels, or the stage or grade of the HCC. No significant differences were found between the MCs density of the patients with and without hepatitis C virus infection, but they were significantly higher in the specimens showing marked sinusoidal capillarisation.CONCLUSION: The lack of any significant correlation between MCs density and the stage or grade of the neoplastic lesions suggests that there is no causal relationship between MCs recruitment and HCC. However, as capillarisation proceeds concurrently with arterial blood supply during hepatocarcinogenesis, MCs may be considered of primary importance in the transition from sinusoidal to capillary-type endothelial cells and the HCC growth.

  12. Derivation, propagation and differentiation of human embryonic stem cells.

    Science.gov (United States)

    Conley, Brock J; Young, Julia C; Trounson, Alan O; Mollard, Richard

    2004-04-01

    Embryonic stem (ES) cells are in vitro cultivated pluripotent cells derived from the inner cell mass (ICM) of the embryonic blastocyst. Attesting to their pluripotency, ES cells can be differentiated into representative derivatives of all three embryonic germ layers (endoderm, ectoderm and mesoderm) both in vitro and in vivo. Although mouse ES cells have been studied for many years, human ES cells have only more recently been derived and successfully propagated. Many biochemical differences and culture requirements between mouse and human ES cells have been described, yet despite these differences the study of murine ES cells has provided important insights into methodologies aimed at generating a greater and more in depth understanding of human ES cell biology. One common feature of both mouse and human ES cells is their capacity to undergo controlled differentiation into spheroid structures termed embryoid bodies (EBs). EBs recapitulate several aspects of early development, displaying regional-specific differentiation programs into derivatives of all three embryonic germ layers. For this reason, EB formation has been utilised as an initial step in a wide range of studies aimed at differentiating both mouse and human ES cells into a specific and desired cell type. Recent reports utilising specific growth factor combinations and cell-cell induction systems have provided alternative strategies for the directed differentiation of cells into a desired lineage. According to each one of these strategies, however, a relatively high cell lineage heterogeneity remains, necessitating subsequent purification steps including mechanical dissection, selective media or fluorescent or magnetic activated cell sorting (FACS and MACS, respectively). In the future, the ability to specifically direct differentiation of human ES cells at 100% efficiency into a desired lineage will allow us to fully explore the potential of these cells in the analysis of early human development, drug

  13. Alloimmune Responses of Humanized Mice to Human Pluripotent Stem Cell Therapeutics

    Directory of Open Access Journals (Sweden)

    Nigel G. Kooreman

    2017-08-01

    Full Text Available There is growing interest in using embryonic stem cell (ESC and induced pluripotent stem cell (iPSC derivatives for tissue regeneration. However, an increased understanding of human immune responses to stem cell-derived allografts is necessary for maintaining long-term graft persistence. To model this alloimmunity, humanized mice engrafted with human hematopoietic and immune cells could prove to be useful. In this study, an in-depth analysis of graft-infiltrating human lymphocytes and splenocytes revealed that humanized mice incompletely model human immune responses toward allogeneic stem cells and their derivatives. Furthermore, using an “allogenized” mouse model, we show the feasibility of reconstituting immunodeficient mice with a functional mouse immune system and describe a key role of innate immune cells in the rejection of mouse stem cell allografts.

  14. Characterization of Microvesicles Released from Human Red Blood Cells

    Directory of Open Access Journals (Sweden)

    Duc Bach Nguyen

    2016-03-01

    Full Text Available Background/Aims: Extracellular vesicles (EVs are spherical fragments of cell membrane released from various cell types under physiological as well as pathological conditions. Based on their size and origin, EVs are classified as exosome, microvesicles (MVs and apoptotic bodies. Recently, the release of MVs from human red blood cells (RBCs under different conditions has been reported. MVs are released by outward budding and fission of the plasma membrane. However, the outward budding process itself, the release of MVs and the physical properties of these MVs have not been well investigated. The aim of this study is to investigate the formation process, isolation and characterization of MVs released from RBCs under conditions of stimulating Ca2+ uptake and activation of protein kinase C. Methods: Experiments were performed based on single cell fluorescence imaging, fluorescence activated cell sorter/flow cytometer (FACS, scanning electron microscopy (SEM, atomic force microscopy (AFM and dynamic light scattering (DLS. The released MVs were collected by differential centrifugation and characterized in both their size and zeta potential. Results: Treatment of RBCs with 4-bromo-A23187 (positive control, lysophosphatidic acid (LPA, or phorbol-12 myristate-13 acetate (PMA in the presence of 2 mM extracellular Ca2+ led to an alteration of cell volume and cell morphology. In stimulated RBCs, exposure of phosphatidylserine (PS and formation of MVs were observed by using annexin V-FITC. The shedding of MVs was also observed in the case of PMA treatment in the absence of Ca2+, especially under the transmitted bright field illumination. By using SEM, AFM and DLS the morphology and size of stimulated RBCs, MVs were characterized. The sizes of the two populations of MVs were 205.8 ± 51.4 nm and 125.6 ± 31.4 nm, respectively. Adhesion of stimulated RBCs and MVs was observed. The zeta potential of MVs was determined in the range from - 40 mV to - 10 m

  15. New frontiers in human cell biology and medicine: can pluripotent stem cells deliver?

    Science.gov (United States)

    Goldstein, Lawrence S B

    2012-11-12

    Human pluripotent stem cells provide enormous opportunities to treat disease using cell therapy. But human stem cells can also drive biomedical and cell biological discoveries in a human model system, which can be directly linked to understanding disease or developing new therapies. Finally, rigorous scientific studies of these cells can and should inform the many science and medical policy issues that confront the translation of these technologies to medicine. In this paper, I discuss these issues using amyotrophic lateral sclerosis as an example.

  16. Subcellular Distribution and Genotoxicity of Silica Nanoparticles 
in Human Bronchial Epithelial Cells

    Directory of Open Access Journals (Sweden)

    Guangqiang ZHAO

    2013-03-01

    Full Text Available Background and objective Silicon nanoparticles are widely used in daily life. Therefore, they attract increased attention because of their potential biotoxicity to the lungs when inhaled. The aims of this study are to explore the organism distribution and genotoxicity of silica nanoparticles in human bronchial epithelial cells (BEAS-2B. Methods The biodistribution of silica with different particle sizes in human bronchial epithelial cells was observed by transmission electron microscopy (TEM. DNA damage was detected by single-cell gel electrophoresis (comet assay. Results TEM revealed that SiO2 nanoparticles with different sizes can be uptaken by cells and be localized in the cytoplasm and the nucleus. Compared with micro-silica, nano-silica in BEAS-2B cells can inflict more severe DNA damage (P<0.05. Conclusion The particle size of silica nanoparticles can be used to determine their distribution in biological cells. Compared with micro-silica, nano-silica has higher genotoxicity.

  17. Bio-batteries and bio-fuel cells: leveraging on electronic charge transfer proteins.

    Science.gov (United States)

    Kannan, A M; Renugopalakrishnan, V; Filipek, S; Li, P; Audette, G F; Munukutla, L

    2009-03-01

    Bio-fuel cells are alternative energy devises based on bio-electrocatalysis of natural substrates by enzymes or microorganisms. Here we review bio-fuel cells and bio-batteries based on the recent literature. In general, the bio-fuel cells are classified based on the type of electron transfer; mediated electron transfer and direct electron transfer or electronic charge transfer (ECT). The ECT of the bio-fuel cells is critically reviewed and a variety of possible applications are considered. The technical challenges of the bio-fuel cells, like bioelectrocatalysis, immobilization of bioelectrocatalysts, protein denaturation etc. are highlighted and future research directions are discussed leveraging on the use of electron charge transfer proteins. In addition, the packaging aspects of the bio-fuel cells are also analyzed and the found that relatively little work has been done in the engineering development of bio-fuel cells.

  18. Two years results of electronic brachytherapy for basal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Rosa Ballester-Sánchez

    2017-06-01

    Full Text Available Purpose: The use of radiation therapy (RT for non-melanoma skin cancer (NMSC has been changing throughout the last century. Over the last decades, the use of radiotherapy has surged with the development of new techniques, applicators, and devices. In recent years, electronic brachytherapy (eBT devices that use small x-ray sources have been introduced as alternative to radionuclide dependence. Nowadays, several devices have been incorporated, with a few series reported, and with a short follow-up, due to the recent introduction of these systems. The purpose of this work is to describe the clinical results of our series after two years follow-up with a specific eBT system. Material and methods: This is a prospective single-center, non-randomized pilot study, to assess clinical results of electronic brachytherapy in basal cell carcinoma using the Esteya® system. In 2014, 40 patients with 60 lesions were treated. Patient follow-up on a regular basis was performed for a period of two years. Results: Twenty-six patients with 44 lesions achieved two years follow-up. A complete response was documented in 95.5% of cases. Toxicity was mild (G1 or G2 in all cases, caused by erythema, erosion, or alopecia. Cosmesis was excellent in 88.6% of cases, and good in the rest. Change in pigmentation was the most frequent cosmetic alteration. Conclusions : This work is special, since the equipment’s treatment voltage was 69.5 kV, and this is the first prospective study with long term follow-up with Esteya®. These preliminary report show excellent results with less toxicity and excellent cosmesis. While surgery has been the treatment of choice, certain patients might benefit from eBT treatment. These are elderly patients with comorbidities or undergoing anticoagulant treatment as well as those who simply refuse surgery or might have other contraindications.

  19. Human Satellite Cell Transplantation and Regeneration from Diverse Skeletal Muscles

    Directory of Open Access Journals (Sweden)

    Xiaoti Xu

    2015-09-01

    Full Text Available Identification of human satellite cells that fulfill muscle stem cell criteria is an unmet need in regenerative medicine. This hurdle limits understanding how closely muscle stem cell properties are conserved among mice and humans and hampers translational efforts in muscle regeneration. Here, we report that PAX7 satellite cells exist at a consistent frequency of 2–4 cells/mm of fiber in muscles of the human trunk, limbs, and head. Xenotransplantation into mice of 50–70 fiber-associated, or 1,000–5,000 FACS-enriched CD56+/CD29+ human satellite cells led to stable engraftment and formation of human-derived myofibers. Human cells with characteristic PAX7, CD56, and CD29 expression patterns populated the satellite cell niche beneath the basal lamina on the periphery of regenerated fibers. After additional injury, transplanted satellite cells robustly regenerated to form hundreds of human-derived fibers. Together, these findings conclusively delineate a source of bona-fide endogenous human muscle stem cells that will aid development of clinical applications.

  20. CD56 marks human dendritic cell subsets with cytotoxic potential

    NARCIS (Netherlands)

    Roothans, D.; Smits, E.; Lion, E.; Tel, J.; Anguille, S.

    2013-01-01

    Human plasmacytoid and myeloid dendritic cells (DCs), when appropriately stimulated, can express the archetypal natural killer (NK)-cell surface marker CD56. In addition to classical DC functions, CD56+ DCs are endowed with an unconventional cytotoxic capacity.

  1. Effects of Human Umbilical Cord Mesenchymal Stem Cells on Human Trophoblast Cell Functions In Vitro

    Directory of Open Access Journals (Sweden)

    Yajing Huang

    2016-01-01

    Full Text Available Trophoblast cell dysfunction is involved in many disorders during pregnancy such as preeclampsia and intrauterine growth restriction. Few treatments exist, however, that target improving trophoblast cell function. Human umbilical cord mesenchymal stem cells (hUCMSCs are capable of self-renewing, can undergo multilineage differentiation, and have homing abilities; in addition, they have immunomodulatory effects and paracrine properties and thus are a prospective source for cell therapy. To identify whether hUCMSCs can regulate trophoblast cell functions, we treated trophoblast cells with hUCMSC supernatant or cocultured them with hUCMSCs. Both treatments remarkably enhanced the migration and invasion abilities of trophoblast cells and upregulated their proliferation ability. At a certain concentration, hUCMSCs also modulated hCG, PIGF, and sEndoglin levels in the trophoblast culture medium. Thus, hUCMSCs have a positive effect on trophoblast cellular functions, which may provide a new avenue for treatment of placenta-related diseases during pregnancy.

  2. Stem Cells: A Renaissance in Human Biology Research.

    Science.gov (United States)

    Wu, Jun; Izpisua Belmonte, Juan Carlos

    2016-06-16

    The understanding of human biology and how it relates to that of other species represents an ancient quest. Limited access to human material, particularly during early development, has restricted researchers to only scratching the surface of this inherently challenging subject. Recent technological innovations, such as single cell "omics" and human stem cell derivation, have now greatly accelerated our ability to gain insights into uniquely human biology. The opportunities afforded to delve molecularly into scarce material and to model human embryogenesis and pathophysiological processes are leading to new insights of human development and are changing our understanding of disease and choice of therapy options.

  3. Adhesion and metabolic activity of human corneal cells on PCL based nanofiber matrices.

    Science.gov (United States)

    Stafiej, Piotr; Küng, Florian; Thieme, Daniel; Czugala, Marta; Kruse, Friedrich E; Schubert, Dirk W; Fuchsluger, Thomas A

    2017-02-01

    In this work, polycaprolactone (PCL) was used as a basic polymer for electrospinning of random and aligned nanofiber matrices. Our aim was to develop a biocompatible substrate for ophthalmological application to improve wound closure in defects of the cornea as replacement for human amniotic membrane. We investigated whether blending the hydrophobic PCL with poly (glycerol sebacate) (PGS) or chitosan (CHI) improves the biocompatibility of the matrices for cell expansion. Human corneal epithelial cells (HCEp) and human corneal keratocytes (HCK) were used for in vitro biocompatibility studies. After optimization of the electrospinning parameters for all blends, scanning electron microscopy (SEM), attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR), and water contact angle were used to characterize the different matrices. Fluorescence staining of the F-actin cytoskeleton of the cells was performed to analyze the adherence of the cells to the different matrices. Metabolic activity of the cells was measured by cell counting kit-8 (CCK-8) for 20days to compare the biocompatibility of the materials. Our results show the feasibility of producing uniform nanofiber matrices with and without orientation for the used blends. All materials support adherence and proliferation of human corneal cell lines with oriented growth on aligned matrices. Although hydrophobicity of the materials was lowered by blending PCL, no increase in biocompatibility or proliferation, as was expected, could be measured. All tested matrices supported the expansion of human corneal cells, confirming their potential as substrates for biomedical applications.

  4. Identification of markers for quiescent pancreatic stellate cells in the normal human pancreas

    DEFF Research Database (Denmark)

    Nielsen, Michael Friberg Bruun; Mortensen, Michael Bau; Detlefsen, Sönke

    2017-01-01

    cells in the normal human pancreas and perisinusoidal cells in the normal human liver. The immunolabelling capacity was evaluated according to a semiquantitative scoring system. Double-IF of the markers of interest together with markers for other periacinar cells was performed. Moreover, the utility...... of histochemical stains for the identification of human qPSCs was examined, and their ultrastructure was revisited by electron microscopy. Adipophilin, CRBP-1, cytoglobin and vinculin were expressed in qHSCs in the liver, whereas cytoglobin and adipophilin were expressed in qPSCs in the pancreas. Adipophilin...... are markers of qPSCs in the normal human pancreas. However, the use of adipophilin as a qPSC marker may be limited due to its high dependence on optimal PATI. Cytoglobin, on the other hand, is a sensitive marker for qPSCs but is expressed in FBs as well....

  5. Neoplastic human embryonic stem cells as a model of radiation resistance of human cancer stem cells.

    Science.gov (United States)

    Dingwall, Steve; Lee, Jung Bok; Guezguez, Borhane; Fiebig, Aline; McNicol, Jamie; Boreham, Douglas; Collins, Tony J; Bhatia, Mick

    2015-09-08

    Studies have implicated that a small sub-population of cells within a tumour, termed cancer stem cells (CSCs), have an enhanced capacity for tumour formation in multiple cancers and may be responsible for recurrence of the disease after treatment, including radiation. Although comparisons have been made between CSCs and bulk-tumour, the more important comparison with respect to therapy is between tumour-sustaining CSC versus normal stem cells that maintain the healthy tissue. However, the absence of normal known counterparts for many CSCs has made it difficult to compare the radiation responses of CSCs with the normal stem cells required for post-radiotherapy tissue regeneration and the maintenance of tissue homeostasis. Here we demonstrate that transformed human embryonic stem cells (t-hESCs), showing features of neoplastic progression produce tumours resistant to radiation relative to their normal counterpart upon injection into immune compromised mice. We reveal that t-hESCs have a reduced capacity for radiation induced cell death via apoptosis and exhibit altered cell cycle arrest relative to hESCs in vitro. t-hESCs have an increased expression of BclXL in comparison to their normal counterparts and re-sensitization of t-hESCs to radiation upon addition of BH3-only mimetic ABT737, suggesting that overexpression of BclXL underpins t-hESC radiation insensitivity. Using this novel discovery platform to investigate radiation resistance in human CSCs, our study indicates that chemotherapy targeting Bcl2-family members may prove to be an adjuvant to radiotherapy capable of targeting CSCs.

  6. Molecular aging and rejuvenation of human muscle stem cells

    DEFF Research Database (Denmark)

    Carlson, Morgan E; Suetta, Charlotte; Conboy, Michael J

    2009-01-01

    Very little remains known about the regulation of human organ stem cells (in general, and during the aging process), and most previous data were collected in short-lived rodents. We examined whether stem cell aging in rodents could be extrapolated to genetically and environmentally variable humans....... Our findings establish key evolutionarily conserved mechanisms of human stem cell aging. We find that satellite cells are maintained in aged human skeletal muscle, but fail to activate in response to muscle attrition, due to diminished activation of Notch compounded by elevated transforming growth...... factor beta (TGF-beta)/phospho Smad3 (pSmad3). Furthermore, this work reveals that mitogen-activated protein kinase (MAPK)/phosphate extracellular signal-regulated kinase (pERK) signalling declines in human muscle with age, and is important for activating Notch in human muscle stem cells. This molecular...

  7. Ultrastructure of interstitial cells in subserosa of human colon

    DEFF Research Database (Denmark)

    Rumessen, Jüri Johannes; Vanderwinden, Jean-Marie; Hansen, Alastair;

    2013-01-01

    We studied the ultrastructure of interstitial cells in the subserosal/adventitial layer in human colon. An interstitial cell type with an ultrastructure intermediate between fibroblast-like cells (FLC) and interstitial cells of Cajal was identified (IC-SS). IC-SS had thin and flattened branching...

  8. Differentiation of neuroepithelia from human embryonic stem cells

    OpenAIRE

    2009-01-01

    We describe the method for in vitro differentiation of neuroepithelial cells from human embryonic stem cells under a chemically defined condition. The protocol is established following the fundamental principle of in vivo neuroectodermal specification. The primitive neuroepithelial cells generated by this protocol can be further induced into neuronal and glia cells with forebrain, mid/hind brain, and spinal cord identities.

  9. Identification of a candidate stem cell in human gallbladder.

    Science.gov (United States)

    Manohar, Rohan; Li, Yaming; Fohrer, Helene; Guzik, Lynda; Stolz, Donna Beer; Chandran, Uma R; LaFramboise, William A; Lagasse, Eric

    2015-05-01

    There are currently no reports of identification of stem cells in human gallbladder. The differences between human gallbladder and intrahepatic bile duct (IHBD) cells have also not been explored. The goals of this study were to evaluate if human fetal gallbladder contains a candidate stem cell population and if fetal gallbladder cells are distinct from fetal IHBD cells. We found that EpCAM+CD44+CD13+ cells represent the cell population most enriched for clonal self-renewal from primary gallbladder. Primary EpCAM+CD44+CD13+ cells gave rise to EpCAM+CD44+CD13+ and EpCAM+CD44+CD13- cells in vitro, and gallbladder cells expanded in vitro exhibited short-term engraftment in vivo. Last, we found that CD13, CD227, CD66, CD26 and CD49b were differentially expressed between gallbladder and IHBD cells cultured in vitro indicating clear phenotypic differences between the two cell populations. Microarray analyses of expanded cultures confirmed that both cell types have unique transcriptional profiles with predicted functional differences in lipid, carbohydrate, nucleic acid and drug metabolism. In conclusion, we have isolated a distinct clonogenic population of epithelial cells from primary human fetal gallbladder with stem cell characteristics and found it to be unique compared to IHBD cells.

  10. Comparative mutagenesis of human cells in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Thilly, W.G.

    1992-05-01

    This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco. (CBS)

  11. Comparative mutagenesis of human cells in vivo and in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Thilly, W.G.

    1992-05-01

    This report discusses measuring methods of point mutations; high density cell cultures for low dose studies; measurement and sequence determination of mutations in DNA; the mutational spectra of styrene oxide and ethlyene oxide in TK-6 cells; mutational spectrum of Cr in human lymphoblast cells; mutational spectra of radon in TK-6 cells; and the mutational spectra of smokeless tobacco. (CBS)

  12. Training human mesenchymal stromal cells for bone tissue engineering applications

    NARCIS (Netherlands)

    Doorn, J.

    2012-01-01

    Human mesenchymal stromal cells (hMSCs) are an interesting source for cell therapies and tissue engineering applications, because these cells are able to differentiate into various target tissues, such as bone, cartilage, fat and endothelial cells. In addition, they secrete a wide array of growth fa

  13. 77 FR 5489 - Identification of Human Cell Lines Project

    Science.gov (United States)

    2012-02-03

    ... working with cells derived from one individual or animal species, only to eventually learn that the cells..., morphology, pathologic or disease-state, hybrid or mixed culture, feeder cells, date of origin, etc), the STR... National Institute of Standards and Technology Identification of Human Cell Lines Project AGENCY: National...

  14. Evaluation of the bleached human enamel by Scanning Electron Microscopy

    DEFF Research Database (Denmark)

    Miranda, Carolina Baptista; Pagani, Clovis; Benetti, Ana Raquel

    2005-01-01

    Since bleaching has become a popular procedure, the effect of peroxides on dental hard tissues is of great interest in research. Purpose: The aim of this in vitro study was to perform a qualitative analysis of the human enamel after the application of in-office bleaching agents, using Scanning......: 2h); G3- four 2-hour exposures to 35% carbamide peroxide (total exposure: 8h); G4- two applications of 35% hydrogen peroxide, which was light-activated with halogen lamp at 700mW/cm² during 7min and remained in contact with enamel for 20min (total exposure: 40min). All bleaching treatments adopted...... analysis performing gold sputter coating under vacuum and were examined using 15kV at 500x and 2000x magnification. Results: Morphological alterations on the enamel surface were similarly detected after bleaching with either 35% carbamide peroxide or 35% hydrogen peroxide. Surface porosities were...

  15. In vitro evaluation of the effects of yttria-alumina-silica microspheres on human keratinocyte cells.

    Science.gov (United States)

    Radu, T; Chiriac, M T; Popescu, O; Simon, V; Simon, S

    2013-02-01

    The behavior of yttria-alumina-silica spray-dried microspheres was investigated in vitro on a human keratinocyte cell line, first to exclude their cytotoxicity. The HaCaT cells were chosen due to their well-characterized phenotype and their phagocytic ability. Microscopic analysis and cell viability tests showed no negative effect of the microspheres on cells morphology and behavior. Scanning electron microscopy and transmission electron microscopy results evidenced the cellular internalization of the microspheres at 48 h after their incubation with cultured cells. The shape, size distribution, structure, composition, and chemical states of the elements on samples surface were analyzed by SEM, transmission electron microscopy, x-ray diffraction, and x-ray photoelectron spectroscopy, because these properties could influence their internalization by cells. The yttrium distribution on the microspheres surface was indicated by fluorescence microscopy imaging. The microspheres dimension and shape inside the cells was in accordance with their dimension and shape before incubation. The microspheres seemed captured and engulfed by the cells in native form and appeared resistant to degradation over the first 48 h. Most of the analyzed cells took up more microspheres, suggesting that the microspheres were actively phagocytosed by the cells and accumulated within the cytoplasm. X-ray photoelectron spectroscopy results on Al and Si atomic environments denoted Al-O-Si crosslinks, which improve the surface protection to corrosion. Copyright © 2012 Wiley Periodicals, Inc.

  16. The evolution of human cells in terms of protein innovation.

    Science.gov (United States)

    Sardar, Adam J; Oates, Matt E; Fang, Hai; Forrest, Alistair R R; Kawaji, Hideya; Gough, Julian; Rackham, Owen J L

    2014-06-01

    Humans are composed of hundreds of cell types. As the genomic DNA of each somatic cell is identical, cell type is determined by what is expressed and when. Until recently, little has been reported about the determinants of human cell identity, particularly from the joint perspective of gene evolution and expression. Here, we chart the evolutionary past of all documented human cell types via the collective histories of proteins, the principal product of gene expression. FANTOM5 data provide cell-type-specific digital expression of human protein-coding genes and the SUPERFAMILY resource is used to provide protein domain annotation. The evolutionary epoch in which each protein was created is inferred by comparison with domain annotation of all other completely sequenced genomes. Studying the distribution across epochs of genes expressed in each cell type reveals insights into human cellular evolution in terms of protein innovation. For each cell type, its history of protein innovation is charted based on the genes it expresses. Combining the histories of all cell types enables us to create a timeline of cell evolution. This timeline identifies the possibility that our common ancestor Coelomata (cavity-forming animals) provided the innovation required for the innate immune system, whereas cells which now form the brain of human have followed a trajectory of continually accumulating novel proteins since Opisthokonta (boundary of animals and fungi). We conclude that exaptation of existing domain architectures into new contexts is the dominant source of cell-type-specific domain architectures.

  17. Effects of apigenin on cell proliferation of human pancreatic carcinoma cell line BxPC-3 in vitro

    Institute of Scientific and Technical Information of China (English)

    Jiancang Ma; Qiang Li; Jun Zhao; Ying Guo; Qinghua Su; Zongzheng Ji

    2007-01-01

    Objective: To observe the effects of apigenin on cell proliferation of human pancreatic carcinoma cell line BxPC-3 in vitro.Methods :The inhibitive effects of apigenin at different concentrations (0 μmol/L, 100 μmol/L, 200 μmol/L, and 400 μmol/L)on human pancreatic carcinoma cell line BxPC-3 were detected by MTT assays, transmission electron microscope, agarose gel electrophoresis and flow cytometry. The immunohistochemistry was used to detect the expression of Bcl-2 and Bax gene. Results:Apigenin at different concentrations could inhibit the proliferation of human pancreatic carcinoma cell lines BxPC-3, and the inhibitive effect was dose-dependent. The cell cycle of pancreatic carcinoma cells was arrested at G2/M phase. The results of immunohistochemistry showed that the density of apigenin increased, and the expression of Bcl-2 gene was reduced gradually. At the same time the expression of Bax gene was enhanced. Conclusion: Apigenin could inhibit the proliferation of human pancreatic carcinoma cell lines BxPC-3 in vitro. The effect of apoptosis was accompanied with the expression of Bcl-2 decrease and Bax increase.

  18. Adult human brain cell culture for neuroscience research.

    Science.gov (United States)

    Gibbons, Hannah M; Dragunow, Mike

    2010-06-01

    Studies of the brain have progressed enormously through the use of in vivo and in vitro non-human models. However, it is unlikely such studies alone will unravel the complexities of the human brain and so far no neuroprotective treatment developed in animals has worked in humans. In this review we discuss the use of adult human brain cell culture methods in brain research to unravel the biology of the normal and diseased human brain. The advantages of using adult human brain cells as tools to study human brain function from both historical and future perspectives are discussed. In particular, studies using dissociated cultures of adult human microglia, astrocytes, oligodendrocytes and neurons are described and the applications of these types of study are evaluated. Alternative sources of human brain cells such as adult neural stem cells, induced pluripotent stem cells and slice cultures of adult human brain tissue are also reviewed. These adult human brain cell culture methods could benefit basic research and more importantly, facilitate the translation of basic neuroscience research to the clinic for the treatment of brain disorders. Copyright 2009 Elsevier Ltd. All rights reserved.

  19. Numerical Modeling of Microbial Fuel Cell Based on Redox Electron Mediator

    Institute of Scientific and Technical Information of China (English)

    Nanqi Ren

    2015-01-01

    To investigate the behavior of redox electron mediator and its impact to power generation of microbial fuel cell ( MFC ) , this study carries out the numerical modeling of a typical two⁃chamber MFC based on assumption of interfacial electron transfer via redox electron mediator and acetate as sole electron donor. The model simulates the development of cell voltage, current, substrate concentration, redox electron mediator concentration, polarization and power density output under defined conditions. The results demonstrate that the developed models can fit the experimental results well on a qualitative basis, and concentration of electron reduced mediator plays a dominant role in electron transfer process, and the mass transfer may constitute the limiting step when its concentration is at a relatively low level. This study not only provides a better understanding of electron redox mediator behavior during power generation, but also suggests a strategy to improve electron transfer in the anode of MFC.

  20. Apoptosis of human pancreatic cancer cells induced by Triptolide

    Institute of Scientific and Technical Information of China (English)

    Guo-Xiong Zhou; Xiao-Ling Ding; Jie-Fei Huang; Hong Zhang; Sheng-Bao Wu; Jian-Ping Cheng; Qun Wei

    2008-01-01

    AIM:To investigate apoptosis in human pancreatic cancer ceils induced by Triptolide (TL),and the relationship between this apoptosis and expression of caspase-3' bcl-2 and bax.METHODS:Human pancreatic cancer cell line SW1990 was cultured in DIEM media for this study.MTT assay was used to determine the cell growth inhibitory rate in vitro.Flow cytometry and TUNEL assay were used to detect the apoptosis of human pancreatic cancer cells before and after TL treatment.RT-PCR was used to detect the expression of apoptosis-associated gene caspase-3' bcl-2 and bax.RESULTS:TL inhibited the growth of human pancreatic cancer cells in a dose-and time-dependent manner.TL induced human pancreatic cancer cells to undergo apoptosis with typically apoptotic characteristics.TUNEL assay showed that after the treatment of human pancreatic cancer cells with 40 ng/mL TL for 12 h and 24 h,the apoptotic rates of human pancreatic cancer cells increased significantly.RT-PCR demonstrated that caspase-3 and bax were significantly up-regulated in SW1990 cells treated with TL while bcl-2 mRNA was not.CONCLUSION:TL is able to induce the apoptosis in human pancreatic cancer cells.This apoptosis may be mediated by up-regulating the expression of apoptosisassociated caspase-3 and bax gene.

  1. Ultrastructure of Cajal-like interstitial cells in the human detrusor

    DEFF Research Database (Denmark)

    Rasmussen, Helle; Rumessen, Jüri J; Hansen, Alastair

    2009-01-01

    of interstitial cells were identified by TEM: ICC-L and fibroblast-like cells (FLC). ICC-L were bipolar with slender (0.04 microm) flattened dendritic-like processes, frequently forming a branching labyrinth network. Caveolae and short membrane-associated dense bands were present. Mitochondria, rough endoplasmic......The aim of this ultrastructural study was to examine the human detrusor for interstitial cells of Cajal (ICC)-like cells (ICC-L) by conventional transmission electron microscopy (TEM) and immuno-transmission electron microscopy (I-TEM) with antibodies directed towards CD117 and CD34. Two main types...... reticulum and Golgi apparatus were observed in the cell somata and cytoplasmic processes. Intermediate filaments were abundant but no thick filaments were found. ICC-L were interconnected by close appositions, gap junctions and peg-and-socket junctions (PSJ) but no specialised contacts to smooth muscle...

  2. Nanoscale Mechanical Stimulation of Human Mesenchymal Stem Cells

    Directory of Open Access Journals (Sweden)

    H Nikukar

    2014-05-01

    We observed significant responses after 1 and 2-week stimulations in cell number, cell shapes and phenotypical markers. Microarray was performed for all groups. Cell count showed normal cell growth with stimulation. However, cell surface area, cell perimeter, and arboration after 1-week stimulation showed significant increases. Immunofluorescent studies have showed significant increase in osteocalcin production after stimulation. Conclusions: Nanoscale mechanical vibration showed significant changes in human mesenchymal stem cell behaviours. Cell morphology changed to become more polygonal and increased expression of the osteoblast markers were noted. These findings with gene regulation changes suggesting nanoscale mechanostimulation has stimulated osteoblastogenesis.  Keywords:  Mesenchymal, Nanoscale, Stem Cells.

  3. Activation of GPR119 Stimulates Human β-Cell Replication and Neogenesis in Humanized Mice with Functional Human Islets

    Science.gov (United States)

    Ansarullah; Free, Colette; Christopherson, Jenica; Chen, Quanhai; Gao, Jie; Liu, Chengyang; Naji, Ali; Rabinovitch, Alex; Guo, Zhiguang

    2016-01-01

    Using humanized mice with functional human islets, we investigated whether activating GPR119 by PSN632408, a small molecular agonist, can stimulate human β-cell regeneration in vivo. Human islets were transplanted under the left kidney capsule of immunodeficient mice with streptozotocin- (STZ-) induced diabetes. The recipient mice were treated with PSN632408 or vehicle and BrdU daily. Human islet graft function in the mice was evaluated by nonfasting glucose levels, oral glucose tolerance, and removal of the grafts. Immunostaining for insulin, glucagon, and BrdU or Ki67 was performed in islet grafts to evaluate α- and β-cell replication. Insulin and CK19 immunostaining was performed to evaluate β-cell neogenesis. Four weeks after human islet transplantation, 71% of PSN632408-treated mice achieved normoglycaemia compared with 24% of vehicle-treated mice. Also, oral glucose tolerance was significantly improved in the PSN632408-treated mice. PSN632408 treatment significantly increased both human α- and β-cell areas in islet grafts and stimulated α- and β-cell replication. In addition, β-cell neogenesis was induced from pancreatic duct cells in the islet grafts. Our results demonstrated that activation of GPR119 increases β-cell mass by stimulating human β-cell replication and neogenesis. Therefore, GPR119 activators may qualify as therapeutic agents to increase human β-cell mass in patients with diabetes. PMID:27413754

  4. Quantitative detection of gold nanoparticles on individual, unstained cancer cells by scanning electron microscopy

    NARCIS (Netherlands)

    Hartsuiker, L.; Es, van P.; Petersen, W.; Leeuwen, van T.G.; Terstappen, L.W.M.M.; Otto, C.

    2011-01-01

    Gold nanoparticles are rapidly emerging for use in biomedical applications. Characterization of the interaction and delivery of nanoparticles to cells through microscopy is important. Scanning electron microscopes have the intrinsic resolution to visualize gold nanoparticles on cells. A novel sample

  5. Quantitative detection of gold nanoparticles on individual, unstained cancer cells by Scanning Electron Microscopy

    NARCIS (Netherlands)

    Hartsuiker, Liesbeth; van Es, Peter; Petersen, Wilhelmina; van Leeuwen, Ton; Terstappen, Leonardus Wendelinus Mathias Marie; Otto, Cornelis

    2011-01-01

    Gold nanoparticles are rapidly emerging for use in biomedical applications. Characterization of the interaction and delivery of nanoparticles to cells through microscopy is important. Scanning electron microscopes have the intrinsic resolution to visualize gold nanoparticles on cells. A novel sample

  6. Analysis of lead toxicity in human cells

    Directory of Open Access Journals (Sweden)

    Gillis Bruce S

    2012-07-01

    Full Text Available Abstract Background Lead is a metal with many recognized adverse health side effects, and yet the molecular processes underlying lead toxicity are still poorly understood. Quantifying the injurious effects of lead is also difficult because of the diagnostic limitations that exist when analyzing human blood and urine specimens for lead toxicity. Results We analyzed the deleterious impact of lead on human cells by measuring its effects on cytokine production and gene expression in peripheral blood mononuclear cells. Lead activates the secretion of the chemokine IL-8 and impacts mitogen-dependent activation by increasing the secretion of the proinflammatory cytokines IL-6 and TNF-α and of the chemokines IL-8 and MIP1-α in the presence of phytohemagglutinin. The recorded changes in gene expression affected major cellular functions, including metallothionein expression, and the expression of cellular metabolic enzymes and protein kinase activity. The expression of 31 genes remained elevated after the removal of lead from the testing medium thereby allowing for the measurement of adverse health effects of lead poisoning. These included thirteen metallothionein transcripts, three endothelial receptor B transcripts and a number of transcripts which encode cellular metabolic enzymes. Cellular responses to lead correlated with blood lead levels and were significantly altered in individuals with higher lead content resultantly affecting the nervous system, the negative regulation of transcription and the induction of apoptosis. In addition, we identified changes in gene expression in individuals with elevated zinc protoporphyrin blood levels and found that genes regulating the transmission of nerve impulses were affected in these individuals. The affected pathways were G-protein mediated signaling, gap junction signaling, synaptic long-term potentiation, neuropathic pain signaling as well as CREB signaling in neurons. Cellular responses to lead were

  7. Electronic Safety Resource Tools -- Supporting Hydrogen and Fuel Cell Commercialization

    Energy Technology Data Exchange (ETDEWEB)

    Barilo, Nick F.

    2014-09-29

    The Pacific Northwest National Laboratory (PNNL) Hydrogen Safety Program conducted a planning session in Los Angeles, CA on April 1, 2014 to consider what electronic safety tools would benefit the next phase of hydrogen and fuel cell commercialization. A diverse, 20-person team led by an experienced facilitator considered the question as it applied to the eight most relevant user groups. The results and subsequent evaluation activities revealed several possible resource tools that could greatly benefit users. The tool identified as having the greatest potential for impact is a hydrogen safety portal, which can be the central location for integrating and disseminating safety information (including most of the tools identified in this report). Such a tool can provide credible and reliable information from a trustworthy source. Other impactful tools identified include a codes and standards wizard to guide users through a series of questions relating to application and specific features of the requirements; a scenario-based virtual reality training for first responders; peer networking tools to bring users from focused groups together to discuss and collaborate on hydrogen safety issues; and a focused tool for training inspectors. Table ES.1 provides results of the planning session, including proposed new tools and changes to existing tools.

  8. In vitro proliferation of adult human beta-cells.

    Directory of Open Access Journals (Sweden)

    Sabine Rutti

    Full Text Available A decrease in functional beta-cell mass is a key feature of type 2 diabetes. Glucagon-like peptide 1 (GLP-1 analogues induce proliferation of rodent beta-cells. However, the proliferative capacity of human beta-cells and its modulation by GLP-1 analogues remain to be fully investigated. We therefore sought to quantify adult human beta-cell proliferation in vitro and whether this is affected by the GLP-1 analogue liraglutide.Human islets from 7 adult cadaveric organ donors were dispersed into single cells. Beta-cells were purified by FACS. Non-sorted cells and the beta-cell enriched ("beta-cells" population were plated on extracellular matrix from rat (804G and human bladder carcinoma cells (HTB9 or bovine corneal endothelial ECM (BCEC. Cells were maintained in culture+/-liraglutide for 4 days in the presence of BrdU.Rare human beta-cell proliferation could be observed either in the purified beta-cell population (0.051±0.020%; 22 beta-cells proliferating out of 84'283 beta-cells counted or in the non-sorted cell population (0.055±0.011%; 104 proliferating beta-cells out of 232'826 beta-cells counted, independently of the matrix or the culture conditions. Liraglutide increased human beta-cell proliferation on BCEC in the non-sorted cell population (0.082±0.034% proliferating beta-cells vs. 0.017±0.008% in control, p<0.05.These results indicate that adult human beta-cell proliferation can occur in vitro but remains an extremely rare event with these donors and particular culture conditions. Liraglutide increases beta-cell proliferation only in the non-sorted cell population and only on BCEC. However, it cannot be excluded that human beta-cells may proliferate to a greater extent in situ in response to natural stimuli.

  9. Extracellular protonation modulates cell-cell interaction mechanics and tissue invasion in human melanoma cells

    Science.gov (United States)

    Hofschröer, Verena; Koch, Kevin Alexander; Ludwig, Florian Timo; Friedl, Peter; Oberleithner, Hans; Stock, Christian; Schwab, Albrecht

    2017-01-01

    Detachment of cells from the primary tumour precedes metastatic progression by facilitating cell release into the tissue. Solid tumours exhibit altered pH homeostasis with extracellular acidification. In human melanoma, the Na+/H+ exchanger NHE1 is an important modifier of the tumour nanoenvironment. Here we tested the modulation of cell-cell-adhesion by extracellular pH and NHE1. MV3 tumour spheroids embedded in a collagen matrix unravelled the efficacy of cell-cell contact loosening and 3D emigration into an environment mimicking physiological confinement. Adhesive interaction strength between individual MV3 cells was quantified using atomic force microscopy and validated by multicellular aggregation assays. Extracellular acidification from pHe7.4 to 6.4 decreases cell migration and invasion but increases single cell detachment from the spheroids. Acidification and NHE1 overexpression both reduce cell-cell adhesion strength, indicated by reduced maximum pulling forces and adhesion energies. Multicellular aggregation and spheroid formation are strongly impaired under acidification or NHE1 overexpression. We show a clear dependence of melanoma cell-cell adhesion on pHe and NHE1 as a modulator. These effects are opposite to cell-matrix interactions that are strengthened by protons extruded via NHE1. We conclude that these opposite effects of NHE1 act synergistically during the metastatic cascade. PMID:28205573

  10. Generation of Corneal Keratocytes from Human Embryonic Stem Cells.

    Science.gov (United States)

    Hertsenberg, Andrew J; Funderburgh, James L

    2016-01-01

    Human Embryonic Stem Cells (hESC) offer an important resource as a limitless supply of any differentiated cell type of the human body. Keratocytes, cells from the corneal stroma, may have the potential for restoration of vision in cell therapy and biomedical engineering applications, but these specialized cells are not readily expanded in vitro. Here we describe a two-part method to produce keratocytes from the H1 hESC cell line. The hESC cells, maintained and expanded in feeder-free culture medium are first differentiated to neural crest cells using the stromal-derived inducing activity (SDIA) of the PA6 mouse embryonic fibroblast cell line. The resulting neural crest cells are selected by their expression of cell-surface CD271 and subsequently cultured as 3D pellets in a defined differentiation medium to induce a keratocyte phenotype.

  11. Derivation of multipotent mesenchymal precursors from human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    2005-06-01

    Full Text Available BACKGROUND: Human embryonic stem cells provide access to the earliest stages of human development and may serve as a source of specialized cells for regenerative medicine. Thus, it becomes crucial to develop protocols for the directed differentiation of embryonic stem cells into tissue-restricted precursors. METHODS AND FINDINGS: Here, we present culture conditions for the derivation of unlimited numbers of pure mesenchymal precursors from human embryonic stem cells and demonstrate multilineage differentiation into fat, cartilage, bone, and skeletal muscle cells. CONCLUSION: Our findings will help to elucidate the mechanism of mesoderm specification during embryonic stem cell differentiation and provide a platform to efficiently generate specialized human mesenchymal cell types for future clinical applications.

  12. Nucleosome Organization in Human Embryonic Stem Cells.

    Directory of Open Access Journals (Sweden)

    Puya G Yazdi

    Full Text Available The fundamental repeating unit of eukaryotic chromatin is the nucleosome. Besides being involved in packaging DNA, nucleosome organization plays an important role in transcriptional regulation and cellular identity. Currently, there is much debate about the major determinants of the nucleosome architecture of a genome and its significance with little being known about its role in stem cells. To address these questions, we performed ultra-deep sequencing of nucleosomal DNA in two human embryonic stem cell lines and integrated our data with numerous epigenomic maps. Our analyses have revealed that the genome is a determinant of nucleosome organization with transcriptionally inactive regions characterized by a "ground state" of nucleosome profiles driven by underlying DNA sequences. DNA sequence preferences are associated with heterogeneous chromatin organization around transcription start sites. Transcription, histone modifications, and DNA methylation alter this "ground state" by having distinct effects on both nucleosome positioning and occupancy. As the transcriptional rate increases, nucleosomes become better positioned. Exons transcribed and included in the final spliced mRNA have distinct nucleosome profiles in comparison to exons not included at exon-exon junctions. Genes marked by the active modification H3K4m3 are characterized by lower nucleosome occupancy before the transcription start site compared to genes marked by the inactive modification H3K27m3, while bivalent domains, genes associated with both marks, lie exactly in the middle. Combinatorial patterns of epigenetic marks (chromatin states are associated with unique nucleosome profiles. Nucleosome organization varies around transcription factor binding in enhancers versus promoters. DNA methylation is associated with increasing nucleosome occupancy and different types of methylations have distinct location preferences within the nucleosome core particle. Finally, computational

  13. Nucleosome Organization in Human Embryonic Stem Cells.

    Science.gov (United States)

    Yazdi, Puya G; Pedersen, Brian A; Taylor, Jared F; Khattab, Omar S; Chen, Yu-Han; Chen, Yumay; Jacobsen, Steven E; Wang, Ping H

    2015-01-01

    The fundamental repeating unit of eukaryotic chromatin is the nucleosome. Besides being involved in packaging DNA, nucleosome organization plays an important role in transcriptional regulation and cellular identity. Currently, there is much debate about the major determinants of the nucleosome architecture of a genome and its significance with little being known about its role in stem cells. To address these questions, we performed ultra-deep sequencing of nucleosomal DNA in two human embryonic stem cell lines and integrated our data with numerous epigenomic maps. Our analyses have revealed that the genome is a determinant of nucleosome organization with transcriptionally inactive regions characterized by a "ground state" of nucleosome profiles driven by underlying DNA sequences. DNA sequence preferences are associated with heterogeneous chromatin organization around transcription start sites. Transcription, histone modifications, and DNA methylation alter this "ground state" by having distinct effects on both nucleosome positioning and occupancy. As the transcriptional rate increases, nucleosomes become better positioned. Exons transcribed and included in the final spliced mRNA have distinct nucleosome profiles in comparison to exons not included at exon-exon junctions. Genes marked by the active modification H3K4m3 are characterized by lower nucleosome occupancy before the transcription start site compared to genes marked by the inactive modification H3K27m3, while bivalent domains, genes associated with both marks, lie exactly in the middle. Combinatorial patterns of epigenetic marks (chromatin states) are associated with unique nucleosome profiles. Nucleosome organization varies around transcription factor binding in enhancers versus promoters. DNA methylation is associated with increasing nucleosome occupancy and different types of methylations have distinct location preferences within the nucleosome core particle. Finally, computational analysis of nucleosome

  14. Immunosurveillance function of human mast cell?

    Institute of Scientific and Technical Information of China (English)

    (O)ner (O)zdemir

    2005-01-01

    Mast cell (MC) is so widely recognized as a critical effector in allergic disorders that it can be difficult to think of MC in any other context. Indeed, MCs are multifunctional and recently shown that MCs can also act as antigen presenters as well as effector elements of human immune system. First observations of their possible role as anti-tumor cells in peri- or intra-tumoral tissue were mentioned five decades ago and a high content of MCs is considered as a favorable prognosis,consistent with this study. Believers of this hypothesis assumed them to be inhibitors of tumor development through their pro-apoptotic and -necrolytic granules e.g.,granzymes and TNF-α. However, some still postulate them to be enhancers of tumor development through their effects on angiogenesis due to mostly tryptase.There are also some data suggesting increased MC density causes tumor development and indicates bad prognosis. Furthermore, since MC-associated mediators have shown to influence various aspects of tumor biology, the net effect of MCs on the development/progression of tumors has been difficult to evaluate. For instance, chymase induces apoptosis in targets; yet,tryptase, another MC protease, is a well-known mitogen.MCs with these various enzyme expression patterns may mediate different functions and the predominant MC type in tissues may be determined by the environmental needs. The coexistence of tryptase-expressing MCs(MCT) and chymase and tryptase-expressing MCs (MCTC)in physiological conditions reflects a naturally occurring balance that contributes to tissue homeostasis. We have recently discussed the role and relevance of MC serine proteases in different bone marrow diseases.

  15. Biological characteristics of cell lines of human dental alveolus

    Institute of Scientific and Technical Information of China (English)

    陈世璋; 黄靖香; 孙明学; 赵斌

    2003-01-01

    Objective To investigate the biological characteristics of cell lines of healthy and diseased human dental alveoli. Methods Primary cell lines from either healthy or diseased human dental alveoli were obtained. Two cell lines, H-258 and H-171 derived from healthy and diseased human tissues respectively, were selected for morphological study and research on their growth and aging, using cell counting, and histochemical and immunohistochemical staining. Results Primary cell lines were successfully established from innormal dental alveoli. After freezing and thawing for three times, cell growth was continued and no morphological alterations were observed. The doubling time was 53.4 hours and mean division index (MDI) was 4‰. Cells were kept normal after twenty generations with no obvious reduction of doubling time and MDI. Of twenty-six primary cell lines derived from healthy human dental alveoli, only three cell lines achieved generation. After freezing and thawing for twice, cultured cells were still alive at a decreased growth speed, with doubling time of 85.9 hours and MDI of 3‰. Both cell lines, H-171 and H-258, shared the characteristics of osteoblast. Conclusions Primary cell lines of diseased human dental alveoli show greater growth potential. All cell lines of dental alveoli share characteristics of osteoblast. The technique we developed may be put into practice for the treatment of abnormal dental alveoli.

  16. Proteasome particle-rich structures are widely present in human epithelial neoplasms: correlative light, confocal and electron microscopy study.

    Directory of Open Access Journals (Sweden)

    Vittorio Necchi

    Full Text Available A novel cytoplasmic structure has been recently characterized by confocal and electron microscopy in H. pylori-infected human gastric epithelium, as an accumulation of barrel-like proteasome reactive particles colocalized with polyubiquitinated proteins, H. pylori toxins and the NOD1 receptor. This proteasome particle-rich cytoplasmic structure (PaCS, a sort of focal proteasome hyperplasia, was also detected in dysplastic cells and was found to be enriched in SHP2 and ERK proteins, known to play a role in H. pylori-mediated gastric carcinogenesis. However, no information is available on its occurrence in neoplastic growths. In this study, surgical specimens of gastric cancer and various other human epithelial neoplasms have been investigated for PaCSs by light, confocal and electron microscopy including correlative confocal and electron microscopy (CCEM. PaCSs were detected in gastric cohesive, pulmonary large cell and bronchioloalveolar, thyroid papillary, parotid gland, hepatocellular, ovarian serous papillary, uterine cervix and colon adenocarcinomas, as well as in pancreatic serous microcystic adenoma. H. pylori bodies, their virulence factors (VacA, CagA, urease, and outer membrane proteins and the NOD1 bacterial proteoglycan receptor were selectively concentrated inside gastric cancer PaCSs, but not in PaCSs from other neoplasms which did, however, retain proteasome and polyubiquitinated proteins reactivity. No evidence of actual microbial infection was obtained in most PaCS-positive neoplasms, except for H. pylori in gastric cancer and capsulated bacteria in a colon cancer case. Particle lysis and loss of proteasome distinctive immunoreactivities were seen in some tumour cell PaCSs, possibly ending in sequestosomes or autophagic bodies. It is concluded that PaCSs are widely represented in human neoplasms and that both non-infectious and infectious factors activating the ubiquitin-proteasome system are likely to be involved in their origin

  17. Proteasome particle-rich structures are widely present in human epithelial neoplasms: correlative light, confocal and electron microscopy study.

    Science.gov (United States)

    Necchi, Vittorio; Sommi, Patrizia; Vanoli, Alessandro; Manca, Rachele; Ricci, Vittorio; Solcia, Enrico

    2011-01-01

    A novel cytoplasmic structure has been recently characterized by confocal and electron microscopy in H. pylori-infected human gastric epithelium, as an accumulation of barrel-like proteasome reactive particles colocalized with polyubiquitinated proteins, H. pylori toxins and the NOD1 receptor. This proteasome particle-rich cytoplasmic structure (PaCS), a sort of focal proteasome hyperplasia, was also detected in dysplastic cells and was found to be enriched in SHP2 and ERK proteins, known to play a role in H. pylori-mediated gastric carcinogenesis. However, no information is available on its occurrence in neoplastic growths. In this study, surgical specimens of gastric cancer and various other human epithelial neoplasms have been investigated for PaCSs by light, confocal and electron microscopy including correlative confocal and electron microscopy (CCEM). PaCSs were detected in gastric cohesive, pulmonary large cell and bronchioloalveolar, thyroid papillary, parotid gland, hepatocellular, ovarian serous papillary, uterine cervix and colon adenocarcinomas, as well as in pancreatic serous microcystic adenoma. H. pylori bodies, their virulence factors (VacA, CagA, urease, and outer membrane proteins) and the NOD1 bacterial proteoglycan receptor were selectively concentrated inside gastric cancer PaCSs, but not in PaCSs from other neoplasms which did, however, retain proteasome and polyubiquitinated proteins reactivity. No evidence of actual microbial infection was obtained in most PaCS-positive neoplasms, except for H. pylori in gastric cancer and capsulated bacteria in a colon cancer case. Particle lysis and loss of proteasome distinctive immunoreactivities were seen in some tumour cell PaCSs, possibly ending in sequestosomes or autophagic bodies. It is concluded that PaCSs are widely represented in human neoplasms and that both non-infectious and infectious factors activating the ubiquitin-proteasome system are likely to be involved in their origin. PaCS detection

  18. Cryopreservation of human embryonic stem cells by vitrification

    Institute of Scientific and Technical Information of China (English)

    周灿权; 麦庆云; 李涛; 庄广伦

    2004-01-01

    Background The efficiency of traditional cryopreservation of human embryonic stem (ES) cells is low, and there have been few attempts to prove new cryopreservation methods effective. This study was designed to evaluate the efficiency of cryopreservation of human ES cells using vitrification method.Methods Human ES cells clumped from an identical cell line were randomly allocated to be cryopreserved by vitrification or by slow freezing. The recovery rates, the growth and differentiation potential of thawed human ES cells were compared between these two groups. The pluripotency of human ES cells after thawing was identified.Results Eighty-one point nine percent (59/72) of human ES cell clumps were recovered after vitrification, while only 22.8% (16/70) were recovered after slow freezing (P<0.01). The colonies after vitrification manifested have not only faster growth but also a lower level of differentiation when compared to colonies subjected to the slow freezing protocol. However, the rates of growth and differentiation in undifferentiated colonies from both groups were identical to the rates in those of non-cryopreserved stem cells after a prolonged culture period. Passage 6 of vitrified human ES cells retained the properties of pluripotent cells, a normal karyotype and expressed the transcription factor OCT-4, stage specific expressed antigen-4 (SSEA-4) and SSEA-3. Teratoma growth of these cells demonstrated the ability to develop into all three germ layers.Conclusions Vitrification is effective in cryopreserving human ES cells. During a prolonged culture, human ES cells retain their pluripotency after cryopreservation.

  19. Electronic control of gene expression and cell behaviour in Escherichia coli through redox signalling

    Science.gov (United States)

    Tschirhart, Tanya; Kim, Eunkyoung; McKay, Ryan; Ueda, Hana; Wu, Hsuan-Chen; Pottash, Alex Eli; Zargar, Amin; Negrete, Alejandro; Shiloach, Joseph; Payne, Gregory F.; Bentley, William E.

    2017-01-01

    The ability to interconvert information between electronic and ionic modalities has transformed our ability to record and actuate biological function. Synthetic biology offers the potential to expand communication `bandwidth' by using biomolecules and providing electrochemical access to redox-based cell signals and behaviours. While engineered cells have transmitted molecular information to electronic devices, the potential for bidirectional communication stands largely untapped. Here we present a simple electrogenetic device that uses redox biomolecules to carry electronic information to engineered bacterial cells in order to control transcription from a simple synthetic gene circuit. Electronic actuation of the native transcriptional regulator SoxR and transcription from the PsoxS promoter allows cell response that is quick, reversible and dependent on the amplitude and frequency of the imposed electronic signals. Further, induction of bacterial motility and population based cell-to-cell communication demonstrates the versatility of our approach and potential to drive intricate biological behaviours.

  20. Sox10 expressing cells in the lateral wall of the aged mouse and human cochlea.

    Directory of Open Access Journals (Sweden)

    Xinping Hao

    Full Text Available Age-related hearing loss (presbycusis is a common human disorder, affecting one in three Americans aged 60 and over. Previous studies have shown that presbyacusis is associated with a loss of non-sensory cells in the cochlear lateral wall. Sox10 is a transcription factor crucial to the development and maintenance of neural crest-derived cells including some non-sensory cell types in the cochlea. Mutations of the Sox10 gene are known to cause various combinations of hearing loss and pigmentation defects in humans. This study investigated the potential relationship between Sox10 gene expression and pathological changes in the cochlear lateral wall of aged CBA/CaJ mice and human temporal bones from older donors. Cochlear tissues prepared from young adult (1-3 month-old and aged (2-2.5 year-old mice, and human temporal bone donors were examined using quantitative immunohistochemical analysis and transmission electron microscopy. Cells expressing Sox10 were present in the stria vascularis, outer sulcus and spiral prominence in mouse and human cochleas. The Sox10(+ cell types included marginal and intermediate cells and outer sulcus cells, including those that border the scala media and those extending into root processes (root cells in the spiral ligament. Quantitative analysis of immunostaining revealed a significant decrease in the number of Sox10(+ marginal cells and outer sulcus cells in aged mice. Electron microscopic evaluation revealed degenerative alterations in the surviving Sox10(+ cells in aged mice. Strial marginal cells in human cochleas from donors aged 87 and older showed only weak immunostaining for Sox10. Decreases in Sox10 expression levels and a loss of Sox10(+ cells in both mouse and human aged ears suggests an important role of Sox10 in the maintenance of structural and functional integrity of the lateral wall. A loss of Sox10(+ cells may also be associated with a decline in the repair capabilities of non-sensory cells in the

  1. Identification of skin immune cells in non-human primates.

    Science.gov (United States)

    Adam, Lucille; Rosenbaum, Pierre; Cosma, Antonio; Le Grand, Roger; Martinon, Frédéric

    2015-11-01

    The skin is a valuable target for vaccine delivery because it contains many immune cell populations, notably antigen presenting cells. Skin immune cells have been extensively described in mice and humans but not in non-human primates, which are pertinent models for immunological research in vaccination. The aim of this work was to describe immune cell populations in the epidermis, dermis and skin draining lymph nodes in cynomolgus macaques by a single 12-parameter flow cytometry protocol. Given that skin cells share several markers, we defined a gating strategy to identify accurately immune cells and to limit contamination of one immune cell population by another. The epidermis contained CD1a(+)CD1c(-) Langerhans cells (LCs), CD3(+) T cells and putative NK cells. The dermis contained CD1a(+)CD1c(-) cells, which were similar to LCs, CD1a(+)CD1c(+) dermal dendritic cells (DDCs), CD163(high)CD11b(+) resident macrophages, CD3(+) T cells and putative NK cells. The skin also contained CD66(+) polymorphonuclear cells in some animals. Thus, immune cell populations in the macaque are similar to those in humans despite some differences in phenotype. In skin draining lymph nodes, we identified migratory LCs, CD1a(+)CD1c(+) DDCs and macrophages. The simultaneous identification of these different immune cells with one panel of markers avoids the use of large amounts of precious sample and may improve the understanding of immune mechanisms in the skin after treatment or vaccination.

  2. [In vitro strategies for human gametes production from stem cells].

    Science.gov (United States)

    Tosca, Lucie; Courtot, Anne-Marie; Bennaceur-Griscelli, Annelise; Tachdjian, Gérard

    2011-10-01

    Embryonic stem cells (ESC) are self-renewal and pluripotent cells that are able to differentiate in vitro into several cell types in favourable conditions. Technical protocols for in vitro gametes production have been developed in mice and human species. The functionality of such differentiated cells is not always analysed and an early meiotic arrest is a current observation. These kinds of experimentations have also been tested from human induced pluripotent stem cells (IPSC). However, differentiation ends shortly at the primordial germ cell stage.

  3. Growth in agarose of human cells infected with cytomegalovirus.

    Science.gov (United States)

    Lang, D J; Montagnier, L; Latarjet, R

    1974-08-01

    After infection by human cytomegalovirus (CMV), human diploid fibroblasts could grow in agarose medium for several generations. Clones of infected cells grew for weeks, although in every case they ultimately underwent lysis owing to the cytopathic effect of the virus. Virus was inoculated at high dilution and after UV irradiation in an effort to derive cells infected with noninfectious defective particles still capable of inducing cell stimulation. Dilute or irradiated virus occasionally yielded large colonies of replicating cells, although permanent transformation was not observed. One clone derived from UV-CMV-infected cells was passaged four times before undergoing lysis. During these passages the cells exhibited alterations in morphology and orientation.

  4. Cytotoxinic Mechanism of Hydroxyapatite Nanoparticles on Human Hepatoma Cell Lines

    Institute of Scientific and Technical Information of China (English)

    CAO Xian-ying; QI Zhi-tao; DAI Hong-lian; YAN Yu-hua; LI Shi-pu

    2003-01-01

    Stable and single-dispersed HAP nanoparticles were synthesized with chemical method assisted by ultrasonic treatment.HAP nanoparticles were surveyed by AFM and Zataplus.The effect on the Bel-7402 human hepatoma cell lines treated with HAP nanoparticles was investigated by the MTT methods and observation of morphology,and the mechanism was studied in changes of cell cycle and ultrastructure.The result shows that inhibition of HAP nanoparticles on the Bel-7402 human hepatoma cell lines is obviously in vitro.HAP nanoparticles the entered cancer cytoplasm,and cell proliferation is stopped at G1 phase of cell cycle,thus,cancer cells die directly.

  5. Electron probe microanalysis of permanent human enamel and dentine. A methodological and quantitative study

    OpenAIRE

    Sánchez-Quevedo, M. C.; Nieto-Albano, O.H.; García, J. M.; Gómez de Ferraris, M. E.; Campos, Antonio

    1998-01-01

    Sample preparation of dental tissues for quantitative electron microprobe analysis has not been critically examined because of the highly mineralized nature of these structures. The present study was designed to establish the most suitable method for the electron probe quantitative determination of calcium in human permanent enamel and dentine while preserving the morphological features. Comparisons of quantitative data obtained with air-drying and freeze-dryin...

  6. Canthin-6-one induces cell death, cell cycle arrest and differentiation in human myeloid leukemia cells.

    Science.gov (United States)

    Vieira Torquato, Heron F; Ribeiro-Filho, Antonio C; Buri, Marcus V; Araújo Júnior, Roberto T; Pimenta, Renata; de Oliveira, José Salvador R; Filho, Valdir C; Macho, Antonio; Paredes-Gamero, Edgar J; de Oliveira Martins, Domingos T

    2017-04-01

    Canthin-6-one is a natural product isolated from various plant genera and from fungi with potential antitumor activity. In the present study, we evaluate the antitumor effects of canthin-6-one in human myeloid leukemia lineages. Kasumi-1 lineage was used as a model for acute myeloid leukemia. Cells were treated with canthin-6-one and cell death, cell cycle and differentiation were evaluated in both total cells (Lin(+)) and leukemia stem cell population (CD34(+)CD38(-)Lin(-/low)). Among the human lineages tested, Kasumi-1 was the most sensitive to canthin-6-one. Canthin-6-one induced cell death with apoptotic (caspase activation, decrease of mitochondrial potential) and necrotic (lysosomal permeabilization, double labeling of annexin V/propidium iodide) characteristics. Moreover, canthin-6-one induced cell cycle arrest at G0/G1 (7μM) and G2 (45μM) evidenced by DNA content, BrdU incorporation and cyclin B1/histone 3 quantification. Canthin-6-one also promoted differentiation of Kasumi-1, evidenced by an increase in the expression of myeloid markers (CD11b and CD15) and the transcription factor PU.1. Furthermore, a reduction of the leukemic stem cell population and clonogenic capability of stem cells were observed. These results show that canthin-6-one can affect Kasumi-1 cells by promoting cell death, cell cycle arrest and cell differentiation depending on concentration used. Canthin-6-one presents an interesting cytotoxic activity against leukemic cells and represents a promising scaffold for the development of molecules for anti-leukemic applications, especially by its anti-leukemic stem cell activity. Copyright © 2017 Elsevier B.V. All rights reserved.

  7. Human organomics: a fresh approach to understanding human development using single-cell transcriptomics.

    Science.gov (United States)

    Camp, J Gray; Treutlein, Barbara

    2017-05-01

    Innovative methods designed to recapitulate human organogenesis from pluripotent stem cells provide a means to explore human developmental biology. New technologies to sequence and analyze single-cell transcriptomes can deconstruct these 'organoids' into constituent parts, and reconstruct lineage trajectories during cell differentiation. In this Spotlight article we summarize the different approaches to performing single-cell transcriptomics on organoids, and discuss the opportunities and challenges of applying these techniques to generate organ-level, mechanistic models of human development and disease. Together, these technologies will move past characterization to the prediction of human developmental and disease-related phenomena. © 2017. Published by The Company of Biologists Ltd.

  8. Human endothelial progenitor cells internalize high-density lipoprotein.

    Science.gov (United States)

    Srisen, Kaemisa; Röhrl, Clemens; Meisslitzer-Ruppitsch, Claudia; Ranftler, Carmen; Ellinger, Adolf; Pavelka, Margit; Neumüller, Josef

    2013-01-01

    Endothelial progenitor cells (EPCs) originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL), and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate), cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal intraellular

  9. Human endothelial progenitor cells internalize high-density lipoprotein.

    Directory of Open Access Journals (Sweden)

    Kaemisa Srisen

    Full Text Available Endothelial progenitor cells (EPCs originate either directly from hematopoietic stem cells or from a subpopulation of monocytes. Controversial views about intracellular lipid traffic prompted us to analyze the uptake of human high density lipoprotein (HDL, and HDL-cholesterol in human monocytic EPCs. Fluorescence and electron microscopy were used to investigate distribution and intracellular trafficking of HDL and its associated cholesterol using fluorescent surrogates (bodipy-cholesterol and bodipy-cholesteryl oleate, cytochemical labels and fluorochromes including horseradish peroxidase and Alexa Fluor® 568. Uptake and intracellular transport of HDL were demonstrated after internalization periods from 0.5 to 4 hours. In case of HDL-Alexa Fluor® 568, bodipy-cholesterol and bodipy-cholesteryl oleate, a photooxidation method was carried out. HDL-specific reaction products were present in invaginations of the plasma membrane at each time of treatment within endocytic vesicles, in multivesicular bodies and at longer periods of uptake, also in lysosomes. Some HDL-positive endosomes were arranged in form of "strings of pearl"- like structures. HDL-positive multivesicular bodies exhibited intensive staining of limiting and vesicular membranes. Multivesicular bodies of HDL-Alexa Fluor® 568-treated EPCs showed multilamellar intra-vacuolar membranes. At all periods of treatment, labeled endocytic vesicles and organelles were apparent close to the cell surface and in perinuclear areas around the Golgi apparatus. No HDL-related particles could be demonstrated close to its cisterns. Electron tomographic reconstructions showed an accumulation of HDL-containing endosomes close to the trans-Golgi-network. HDL-derived bodipy-cholesterol was localized in endosomal vesicles, multivesicular bodies, lysosomes and in many of the stacked Golgi cisternae and the trans-Golgi-network Internalized HDL-derived bodipy-cholesteryl oleate was channeled into the lysosomal

  10. 75 FR 64248 - Approval for Manufacturing Authority Foreign-Trade Zone 196 ATC Logistics & Electronics (Cell...

    Science.gov (United States)

    2010-10-19

    ... & Electronics (Cell Phone Kitting) Fort Worth, TX Pursuant to its authority under the Foreign-Trade Zones Act of... following Order: Whereas, ATC Logistics & Electronics (ATCLE), an operator of Foreign-Trade Zone 196, has... procedures within FTZ 196 on behalf of ATC Logistics & Electronics, as described in the application...

  11. Structural deteriorations of the human peritoneum during laparoscopic cholecystectomy. A transmission electron microscopic study.

    Science.gov (United States)

    Tarhan, Omer Ridvan; Barut, Ibrahim; Ozogul, Candan; Bozkurt, Serkan; Baykara, Basak; Bulbul, Mahmut

    2013-08-01

    In previous studies, changes in the surface of the peritoneum during laparoscopic surgery are well defined. Nevertheless, almost all of these studies were performed on rodents via scanning electron microscopy. In the present study, structural alterations of the mesothelial cells of peritoneum were examined during laparoscopic cholecystectomy using transmission electron microscopy. Twenty patients with symptomatic cholelithiasis were included in the study. Peritoneal biopsy was performed immediately after CO2 pneumoperitoneum creation and at the end of surgery just before gallbladder removal. Biopsies were taken from the right upper quadrant, i.e., apart from operative manipulation. Peritoneal sample cross-sections were compared using transmission electron microscopy. The carbon dioxide pneumoperitoneum during laparoscopic cholecystectomy caused deteriorations of the peritoneal mesothelium. Apoptosis were developed in mesothelial cells. Bulging of mesothelial cells, irregular cell junctions, focal intercellular clefts, apical cell membrane degeneration, deep nuclear invaginations, and lipid droplets in the cytoplasm of the mesothelial cells were other remarkable findings. Mesothelial edema also was determined. As seen in previous studies, basement membrane nudity appeared after carbon dioxide pneumoperitoneum could be attributable to mesothelial cell apoptosis, deterioration of the cell structure, and cell organelles.

  12. Human dental pulp stem cells: Applications in future regenerative medicine.

    Science.gov (United States)

    Potdar, Pravin D; Jethmalani, Yogita D

    2015-06-26

    Stem cells are pluripotent cells, having a property of differentiating into various types of cells of human body. Several studies have developed mesenchymal stem cells (MSCs) from various human tissues, peripheral blood and body fluids. These cells are then characterized by cellular and molecular markers to understand their specific phenotypes. Dental pulp stem cells (DPSCs) are having a MSCs phenotype and they are differentiated into neuron, cardiomyocytes, chondrocytes, osteoblasts, liver cells and β cells of islet of pancreas. Thus, DPSCs have shown great potentiality to use in regenerative medicine for treatment of various human diseases including dental related problems. These cells can also be developed into induced pluripotent stem cells by incorporation of pluripotency markers and use for regenerative therapies of various diseases. The DPSCs are derived from various dental tissues such as human exfoliated deciduous teeth, apical papilla, periodontal ligament and dental follicle tissue. This review will overview the information about isolation, cellular and molecular characterization and differentiation of DPSCs into various types of human cells and thus these cells have important applications in regenerative therapies for various diseases. This review will be most useful for postgraduate dental students as well as scientists working in the field of oral pathology and oral medicine.

  13. Role of human mast cells and basophils in bronchial asthma.

    Science.gov (United States)

    Marone, Gianni; Triggiani, Massimo; Genovese, Arturo; De Paulis, Amato

    2005-01-01

    Mast cells and basophils are the only cells expressing the tetrameric (alphabetagamma2) structure of the high affinity receptor for IgE (FcepsilonRI) and synthesizing histamine in humans. Human FcepsilonRI+ cells are conventionally considered primary effector cells of bronchial asthma. There is now compelling evidence that these cells differ immunologically, biochemically, and pharmacologically, which suggests that they might play distinct roles in the appearance and fluctuation of the asthma phenotype. Recent data have revealed the complexity of the involvement of human mast cells and basophils in asthma and have shed light on the control of recruitment and activation of these cells in different lung compartments. Preliminary evidence suggests that these cells might not always be detrimental in asthma but, under some circumstances, they might exert a protective effect by modulating certain aspects of innate and acquired immunity and allergic inflammation.

  14. INDUCTION OF APOPTOSIS BY SeO2 IN HUMAN LUNG CARCINOMA CELL LINE GLC-82

    Institute of Scientific and Technical Information of China (English)

    陈维香; 曹晓哲; 朱任之; 刘炜

    2004-01-01

    Objective: To investigate the effect of selenium dioxide (SeO2) on human pulmonary adenocarcinoma GLC-82 cell lines to reveal its probable mechanism and the relationship between apoptosis and SeO2. Methods: Methyl thiazolyl tetrazolium (MTT) method, flow cytometry (FCM), DNA agarose gel electrophoresis, light and electron microscope were used to study cell apoptosis in human pulmonary adenocarcinoma cell line GLC-82 treated by SeO2 at different concentrations (3, 10, 30 (mol/L) and for different times (24, 48, and 72 h). Results: SeO2 significantly inhibited the proliferation and induced the cell apoptosis of GLC-82 at the different concentrations after treatment of 48 h and 72 h. Conclusion: Selenium dioxide could inhibit the growth of lung cancer GLC-82 cells through inducing apoptosis. The effect of inhibition is dose-dependant and time-dependant.

  15. Identification of human fibroblast cell lines as a feeder layer for human corneal epithelial regeneration.

    Directory of Open Access Journals (Sweden)

    Rong Lu

    Full Text Available There is a great interest in using epithelium generated in vitro for tissue bioengineering. Mouse 3T3 fibroblasts have been used as a feeder layer to cultivate human epithelia including corneal epithelial cells for more than 3 decades. To avoid the use of xeno-components, we evaluated human fibroblasts as an alternative feeder supporting human corneal epithelial regeneration. Five human fibroblast cell lines were used for evaluation with mouse 3T3 fibroblasts as a control. Human epithelial cells isolated from fresh corneal limbal tissue were seeded on these feeders. Colony forming efficiency (CFE and cell growth capacity were evaluated on days 5-14. The phenotype of the regenerated epithelia was evaluated by morphology and immunostaining with epithelial markers. cDNA microarray was used to analyze the gene expression profile of the supportive human fibroblasts. Among 5 strains of human fibroblasts evaluated, two newborn foreskin fibroblast cell lines, Hs68 and CCD1112Sk, were identified to strongly support human corneal epithelial growth. Tested for 10 passages, these fibroblasts continually showed a comparative efficiency to the 3T3 feeder layer for CFE and growth capacity of human corneal epithelial cells. Limbal epithelial cells seeded at 1 × 10(4 in a 35-mm dish (9.6 cm(2 grew to confluence (about 1.87-2.41 × 10(6 cells in 12-14 days, representing 187-241 fold expansion with over 7-8 doublings on these human feeders. The regenerated epithelia expressed K3, K12, connexin 43, p63, EGFR and integrin β1, resembling the phenotype of human corneal epithelium. DNA microarray revealed 3 up-regulated and 10 down-regulated genes, which may be involved in the functions of human fibroblast feeders. These findings demonstrate that commercial human fibroblast cell lines support human corneal epithelial regeneration, and have potential use in tissue bioengineering for corneal reconstruction.

  16. Microtubules in Plant Cells: Strategies and Methods for Immunofluorescence, Transmission Electron Microscopy and Live Cell Imaging

    Science.gov (United States)

    Celler, Katherine; Fujita, Miki; Kawamura, Eiko; Ambrose, Chris; Herburger, Klaus; Wasteneys, Geoffrey O.

    2016-01-01

    Microtubules are required throughout plant development for a wide variety of processes, and different strategies have evolved to visualize and analyze them. This chapter provides specific methods that can be used to analyze microtubule organization and dynamic properties in plant systems and summarizes the advantages and limitations for each technique. We outline basic methods for preparing samples for immunofluorescence labelling, including an enzyme-based permeabilization method, and a freeze-shattering method, which generates microfractures in the cell wall to provide antibodies access to cells in cuticle-laden aerial organs such as leaves. We discuss current options for live cell imaging of MTs with fluorescently tagged proteins (FPs), and provide chemical fixation, high pressure freezing/freeze substitution, and post-fixation staining protocols for preserving MTs for transmission electron microscopy and tomography. PMID:26498784

  17. Genetic engineering of human pluripotent cells using TALE nucleases.

    Science.gov (United States)

    Hockemeyer, Dirk; Wang, Haoyi; Kiani, Samira; Lai, Christine S; Gao, Qing; Cassady, John P; Cost, Gregory J; Zhang, Lei; Santiago, Yolanda; Miller, Jeffrey C; Zeitler, Bryan; Cherone, Jennifer M; Meng, Xiangdong; Hinkley, Sarah J; Rebar, Edward J; Gregory, Philip D; Urnov, Fyodor D; Jaenisch, Rudolf

    2011-07-07

    Targeted genetic engineering of human pluripotent cells is a prerequisite for exploiting their full potential. Such genetic manipulations can be achieved using site-specific nucleases. Here we engineered transcription activator-like effector nucleases (TALENs) for five distinct genomic loci. At all loci tested we obtained human embryonic stem cell (ESC) and induced pluripotent stem cell (iPSC) clones carrying transgenic cassettes solely at the TALEN-specified location. Our data suggest that TALENs employing the specific architectures described here mediate site-specific genome modification in human pluripotent cells with similar efficiency and precision as do zinc-finger nucleases (ZFNs).

  18. Purification and cultivation of human pituitary growth hormone secreting cells

    Science.gov (United States)

    Hymer, W. C.

    1978-01-01

    The maintainance of actively secreting human pituitary growth hormone cells (somatotrophs) in vitro was studied. The primary approach was the testing of agents which may be expected to increase the release of the human growth hormone (hGH). A procedure for tissue procurement is described along with the methodologies used to dissociate human pituitary tissue (obtained either at autopsy or surgery) into single cell suspensions. The validity of the Biogel cell column perfusion system for studying the dynamics of GH release was developed and documented using a rat pituitary cell system.

  19. Persistent donor cell gene expression among human induced pluripotent stem cells contributes to differences with human embryonic stem cells.

    Directory of Open Access Journals (Sweden)

    Zhumur Ghosh

    Full Text Available Human induced pluripotent stem cells (hiPSCs generated by de-differentiation of adult somatic cells offer potential solutions for the ethical issues surrounding human embryonic stem cells (hESCs, as well as their immunologic rejection after cellular transplantation. However, although hiPSCs have been described as "embryonic stem cell-like", these cells have a distinct gene expression pattern compared to hESCs, making incomplete reprogramming a potential pitfall. It is unclear to what degree the difference in tissue of origin may contribute to these gene expression differences. To answer these important questions, a careful transcriptional profiling analysis is necessary to investigate the exact reprogramming state of hiPSCs, as well as analysis of the impression, if any, of the tissue of origin on the resulting hiPSCs. In this study, we compare the gene profiles of hiPSCs derived from fetal fibroblasts, neonatal fibroblasts, adipose stem cells, and keratinocytes to their corresponding donor cells and hESCs. Our analysis elucidates the overall degree of reprogramming within each hiPSC line, as well as the "distance" between each hiPSC line and its donor cell. We further identify genes that have a similar mode of regulation in hiPSCs and their corresponding donor cells compared to hESCs, allowing us to specify core sets of donor genes that continue to be expressed in each hiPSC line. We report that residual gene expression of the donor cell type contributes significantly to the differences among hiPSCs and hESCs, and adds to the incompleteness in reprogramming. Specifically, our analysis reveals that fetal fibroblast-derived hiPSCs are closer to hESCs, followed by adipose, neonatal fibroblast, and keratinocyte-derived hiPSCs.

  20. On the development of extragonadal and gonadal human germ cells

    Directory of Open Access Journals (Sweden)

    A. Marijne Heeren

    2016-02-01

    Full Text Available Human germ cells originate in an extragonadal location and have to migrate to colonize the gonadal primordia at around seven weeks of gestation (W7, or five weeks post conception. Many germ cells are lost along the way and should enter apoptosis, but some escape and can give rise to extragonadal germ cell tumors. Due to the common somatic origin of gonads and adrenal cortex, we investigated whether ectopic germ cells were present in the human adrenals. Germ cells expressing DDX4 and/or POU5F1 were present in male and female human adrenals in the first and second trimester. However, in contrast to what has been described in mice, where ‘adrenal’ and ‘ovarian’ germ cells seem to enter meiosis in synchrony, we were unable to observe meiotic entry in human ‘adrenal’ germ cells until W22. By contrast, ‘ovarian’ germ cells at W22 showed a pronounced asynchronous meiotic entry. Interestingly, we observed that immature POU5F1+ germ cells in both first and second trimester ovaries still expressed the neural crest marker TUBB3, reminiscent of their migratory phase. Our findings highlight species-specific differences in early gametogenesis between mice and humans. We report the presence of a population of ectopic germ cells in the human adrenals during development.

  1. Embryonic death and the creation of human embryonic stem cells

    OpenAIRE

    Landry, Donald W.; Zucker, Howard A.

    2004-01-01

    The creation of human embryonic stem cells through the destruction of a human embryo pits the value of a potential therapeutic tool against that of an early human life. This contest of values has resulted in a polarized debate that neglects areas of common interest and perspective. We suggest that a common ground for pursuing research on human embryonic stem cells can be found by reconsidering the death of the human embryo and by applying to this research the ethical norms of essential organ ...

  2. Embryonic death and the creation of human embryonic stem cells.

    Science.gov (United States)

    Landry, Donald W; Zucker, Howard A

    2004-11-01

    The creation of human embryonic stem cells through the destruction of a human embryo pits the value of a potential therapeutic tool against that of an early human life. This contest of values has resulted in a polarized debate that neglects areas of common interest and perspective. We suggest that a common ground for pursuing research on human embryonic stem cells can be found by reconsidering the death of the human embryo and by applying to this research the ethical norms of essential organ donation.

  3. Human induced pluripotent stem cells on autologous feeders.

    Directory of Open Access Journals (Sweden)

    Kazutoshi Takahashi

    Full Text Available BACKGROUND: For therapeutic usage of induced Pluripotent Stem (iPS cells, to accomplish xeno-free culture is critical. Previous reports have shown that human embryonic stem (ES cells can be maintained in feeder-free condition. However, absence of feeder cells can be a hostile environment for pluripotent cells and often results in karyotype abnormalities. Instead of animal feeders, human fibroblasts can be used as feeder cells of human ES cells. However, one still has to be concerned about the existence of unidentified pathogens, such as viruses and prions in these non-autologous feeders. METHODOLOGY/PRINCIPAL FINDINGS: This report demonstrates that human induced Pluripotent Stem (iPS cells can be established and maintained on isogenic parental feeder cells. We tested four independent human skin fibroblasts for the potential to maintain self-renewal of iPS cells. All the fibroblasts tested, as well as their conditioned medium, were capable of maintaining the undifferentiated state and normal karyotypes of iPS cells. Furthermore, human iPS cells can be generated on isogenic parental fibroblasts as feeders. These iPS cells carried on proliferation over 19 passages with undifferentiated morphologies. They expressed undifferentiated pluripotent cell markers, and could differentiate into all three germ layers via embryoid body and teratoma formation. CONCLUSIONS/SIGNIFICANCE: These results suggest that autologous fibroblasts can be not only a source for iPS cells but also be feeder layers. Our results provide a possibility to solve the dilemma by using isogenic fibroblasts as feeder layers of iPS cells. This is an important step toward the establishment of clinical grade iPS cells.

  4. Stages of Cell Cannibalism--Entosis--in Normal Human Keratinocyte Culture.

    Science.gov (United States)

    Garanina, A S; Khashba, L A; Onishchenko, G E

    2015-11-01

    Entosis is a type of cell cannibalism during which one cell penetrates into another cell and usually dies inside it. Researchers mainly pay attention to initial and final stages of entosis. Besides, tumor cells in suspension are the primary object of studies. In the present study, we investigated morphological changes of both cells-participants of entosis during this process. The substrate-dependent culture of human normal keratinocytes HaCaT was chosen for the work. A combination of light microscopy and scanning electron microscopy was used to prove that one cell was completely surrounded by the plasma membrane of another cell. We investigated such "cell-in-cell" structures and described the structural and functional changes of both cells during entosis. The outer cell nucleus localization and shape were changed. Gradual degradation of the inner cell nucleus and of the junctions between the inner and the outer cells was revealed. Moreover, repeated redistribution of the outer cell membrane organelles (Golgi apparatus, lysosomes, mitochondria, and autophagosomes), rearrangement of its cytoskeleton, and change in the lysosomal, autophagosomal, and mitochondrial state in both entotic cells were observed during entosis. On the basis of these data, we divided entosis into five stages that make it possible to systematize description of this type of cell death.

  5. Human-induced pluripotent stem cells from blood cells of healthy donors and patients with acquired blood disorders

    OpenAIRE

    2009-01-01

    Human induced pluripotent stem (iPS) cells derived from somatic cells hold promise to develop novel patient-specific cell therapies and research models for inherited and acquired diseases. We and others previously reprogrammed human adherent cells, such as postnatal fibroblasts to iPS cells, which resemble adherent embryonic stem cells. Here we report derivation of iPS cells from postnatal human blood cells and the potential of these pluripotent cells for disease modeling. Multiple human iPS ...

  6. Cell viability evaluation of transdifferentiated endothelial-like cells by quantitative electron-probe X-ray microanalysis for tissue engineering.

    Science.gov (United States)

    Vico, Manuel; Rodríguez-Morata, Alejandro; Garzón, Ingrid; Campos, Fernando; Jaimes-Parra, Boris; Pérez-Köhler, Barbara; Buján, Julia; Alaminos, Miguel; Sánchez-Quevedo, M Carmen

    2015-11-01

    Development of an efficient vascular substitute by tissue engineering is strongly dependent on endothelial cell viability. The aim of this study was to evaluate cell viability of transdifferentiated endothelial-like cells (Tr-ELC) by using for the first time electron probe X-ray microanalysis (EPXMA), not only to accurately analyze cell viability by quantifying the intracellular ionic concentrations, but also to establish their possible use in vascular tissue engineering protocols. Human umbilical cord Wharton's jelly stem cells (HWJSC) and endothelial cells from the human umbilical vein (HUVEC) were isolated and cultured. Transdifferentiation from HWJSC to the endothelial phenotype was induced. EPXMA was carried out to analyze HUVEC, HWJSC and Tr-ELC cells by using a scanning electron microscope equipped with an EDAX DX-4 microanalytical system and a solid-state backscattered electron detector. To determine total ion content, the peak-to-local-background (P/B) ratio method was used with reference to standards composed of dextran containing known amounts of inorganic salts. Our results revealed a high K/Na ratio in Tr-ELC (9.41), in association with the maintenance of the intracellular levels of chlorine, phosphorous and magnesium and an increase of calcium (p=0.031) and sulfur (p=0.022) as compared to HWJSC. Calcium levels were similar for HUVEC and Tr-ELC. These results ensure that transdifferentiated cells are highly viable and resemble the phenotypic and microanalytical profile of endothelial cells. Tr-ELC induced from HWJSC may fulfill the requirements for use in tissue engineering protocols applied to the vascular system at the viability and microanalytical levels.

  7. Questions on unusual Mimivirus-like structures observed in human cells [version 1; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Elena Angela Lusi

    2017-03-01

    Full Text Available Background: Mimiviruses or giant viruses that infect amoebas have the ability to retain the Gram stain, which is usually used to colour bacteria. There is some evidence suggesting that Mimiviruses can also infect human cells. Guided by these premises, we performed a routine Gram stain on a variety of human specimens to see if we could detect the same Gram positive blue granules that identify Mimiviruses in the amoebas. Methods: We analysed 24 different human specimens (liver, brain, kidney, lymph node and ovary using Gram stain histochemistry, electron microscopy immunogold, high resolution mass spectrometry and protein identification. Results: We detected in the human cells Gram positive granules that were distinct from bacteria. The fine blue granules displayed the same pattern of the Gram positive granules that diagnose Mimiviruses in the cytoplasm of the amoebas. Electron microscopy confirmed the presence of human Mimiviruses-like structures and mass spectrometry identified histone H4 peptides, which had the same footprints as giant viruses. However, some differences were noted: the Mimivirus-like structures identified in the human cells were ubiquitous and manifested a distinct mammalian retroviral antigenicity. Conclusions: Our main hypotheses are that the structures could be either giant viruses having a retroviral antigenicity or ancestral cellular components having a viral origin. However, other possible alternatives have been proposed to explain the nature and function of the newly identified structures.

  8. Modelling familial dysautonomia in human induced pluripotent stem cells

    OpenAIRE

    Lee, Gabsang; Studer, Lorenz

    2011-01-01

    Induced pluripotent stem (iPS) cells have considerable promise as a novel tool for modelling human disease and for drug discovery. While the generation of disease-specific iPS cells has become routine, realizing the potential of iPS cells in disease modelling poses challenges at multiple fronts. Such challenges include selecting a suitable disease target, directing the fate of iPS cells into symptom-relevant cell populations, identifying disease-related phenotypes and showing reversibility of...

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

    Science.gov (United States)

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

    2016-01-27

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

  10. Generation of human-induced pluripotent stem cells.

    Science.gov (United States)

    Park, In-Hyun; Lerou, Paul H; Zhao, Rui; Huo, Hongguang; Daley, George Q

    2008-01-01

    Pluripotent cells, such as embryonic stem cells, are invaluable tools for research and can potentially serve as a source of cell- and tissue-replacement therapy. Rejection after transplantation of cells and tissue derived from embryonic stem cells is a significant obstacle to their clinical use. Recently, human somatic cells have been reprogrammed directly to pluripotency by ectopic expression of four transcription factors (Oct4, Sox2, Klf4 and Myc) to yield induced pluripotent stem (iPS) cells. Human iPS cells are a potential source of patient-specific pluripotent stem cells that would bypass immune rejection. iPS cells can also be used to study diseases for which there are no adequate human in vitro or animal models. In this protocol, we describe how to establish primary human fibroblasts lines and how to derive iPS cells by retroviral transduction of reprogramming factors. Overall, it takes 2 months to complete reprogramming human primary fibroblasts starting from biopsy.

  11. Tissuelike 3D Assemblies of Human Broncho-Epithelial Cells

    Science.gov (United States)

    Goodwin, Thomas J.

    2010-01-01

    Three-dimensional (3D) tissuelike assemblies (TLAs) of human broncho-epithelial (HBE) cells have been developed for use in in vitro research on infection of humans by respiratory viruses. The 2D monolayer HBE cell cultures heretofore used in such research lack the complex cell structures and interactions characteristic of in vivo tissues and, consequently, do not adequately emulate the infection dynamics of in-vivo microbial adhesion and invasion. In contrast, the 3D HBE TLAs are characterized by more-realistic reproductions of the geometrical and functional complexity, differentiation of cells, cell-to-cell interactions, and cell-to-matrix interactions characteristic of human respiratory epithelia. Hence, the 3D HBE TLAs are expected to make it possible to perform at least some of the research in vitro under more-realistic conditions, without need to infect human subjects. The TLAs are grown on collagen-coated cyclodextran microbeads under controlled conditions in a nutrient liquid in the simulated microgravitational environment of a bioreactor of the rotating- wall-vessel type. Primary human mesenchymal bronchial-tracheal cells are used as a foundation matrix, while adult human bronchial epithelial immortalized cells are used as the overlying component. The beads become coated with cells, and cells on adjacent beads coalesce into 3D masses. The resulting TLAs have been found to share significant characteristics with in vivo human respiratory epithelia including polarization, tight junctions, desmosomes, and microvilli. The differentiation of the cells in these TLAs into tissues functionally similar to in vivo tissues is confirmed by the presence of compounds, including villin, keratins, and specific lung epithelium marker compounds, and by the production of tissue mucin. In a series of initial infection tests, TLA cultures were inoculated with human respiratory syncytial viruses and parainfluenza type 3 viruses. Infection was confirmed by photomicrographs that

  12. The Isolation and Characterization of Human Prostate Cancer Stem Cells

    Science.gov (United States)

    2015-05-01

    IGF1, SOX15, BMPR1B, TGFBR1, etc), which fall into distinct GO categories including SC, development, stress response, and wound healing (unpublished...prostate cancer through the elucidation of the role of cancer stem cells in the pathogenesis of the disease. During the past year, we have made the...studies, ii) in vitro co-culture of human prostate cancer cells (established cell lines and primary patient samples) with human prostate fibroblasts

  13. Isolation, identification and differentiation of human embryonic cartilage stem cells.

    Science.gov (United States)

    Fu, Changhao; Yan, Zi; Xu, Hao; Zhang, Chen; Zhang, Qi; Wei, Anhui; Yang, Xi; Wang, Yi

    2015-07-01

    We isolated human embryonic cartilage stem cells (hECSCs), a novel stem cell population, from the articular cartilage of eight-week-old human embryos. These stem cells demonstrated a marker expression pattern and differentiation potential intermediate to those of human embryonic stem cells (hESCs) and human adult stem cells (hASCs). hECSCs expressed markers associated with both hESCs (OCT4, NANOG, SOX2, SSEA-3 and SSEA-4) and human adult stem cells (hASCs) (CD29, CD44, CD90, CD73 and CD10). These cells also differentiated into adipocytes, osteoblasts, chondrocytes, neurons and islet-like cells under specific inducing conditions. We identified N(6), 2'-O-dibutyryl cyclic adenosine 3':5'-monophosphate (Bt2cAMP) as an inducer of chondrogenic differentiation in hECSCs. Similar results using N(6), 2'-O-dibutyryl cyclic adenosine 3':5'-monophosphate (Bt2cAMP) were obtained for two other types of human embryonic tissue-derived stem cells, human embryonic hepatic stem cells (hEHSCs) and human embryonic amniotic fluid stem cells (hEASCs), both of which exhibited a marker expression pattern similar to that of hECSCs. The isolation of hECSCs and the discovery that N(6), 2'-O-dibutyryl cyclic adenosine 3':5'-monophosphate (Bt2cAMP) induces chondrogenic differentiation in different stem cell populations might aid the development of strategies in tissue engineering and cartilage repair.

  14. Sphere-forming cell subpopulations with cancer stem cell properties in human hepatoma cell lines

    Directory of Open Access Journals (Sweden)

    Chen Lei

    2011-06-01

    Full Text Available Abstract Background Cancer stem cells (CSCs are regarded as the cause of tumor formation and recurrence. The isolation and identification of CSCs could help to develop novel therapeutic strategies specifically targeting CSCs. Methods Human hepatoma cell lines were plated in stem cell conditioned culture system allowed for sphere forming. To evaluate the stemness characteristics of spheres, the self-renewal, proliferation, chemoresistance, tumorigenicity of the PLC/PRF/5 sphere-forming cells, and the expression levels of stem cell related proteins in the PLC/PRF/5 sphere-forming cells were assessed, comparing with the parental cells. The stem cell RT-PCR array was performed to further explore the biological properties of liver CSCs. Results The PLC/PRF/5, MHCC97H and HepG2 cells could form clonal nonadherent 3-D spheres and be serially passaged. The PLC/PRF/5 sphere-forming cells possessed a key criteria that define CSCs: persistent self-renewal, extensive proliferation, drug resistance, overexpression of liver CSCs related proteins (Oct3/4, OV6, EpCAM, CD133 and CD44. Even 500 sphere-forming cells were able to form tumors in NOD/SCID mice, and the tumor initiating capability was not decreased when spheres were passaged. Besides, downstream proteins DTX1 and Ep300 of the CSL (CBF1 in humans, Suppressor of hairless in Drosophila and LAG1 in C. elegans -independent Notch signaling pathway were highly expressed in the spheres, and a gamma-secretase inhibitor MRK003 could significantly inhibit the sphere formation ability. Conclusions Nonadherent tumor spheres from hepatoma cell lines cultured in stem cell conditioned medium possess liver CSC properties, and the CSL-independent Notch signaling pathway may play a role in liver CSCs.

  15. Vasoprotective effects of human CD34+ cells: towards clinical applications

    Directory of Open Access Journals (Sweden)

    Lerman Amir

    2009-07-01

    Full Text Available Abstract Background The development of cell-based therapeutics for humans requires preclinical testing in animal models. The use of autologous animal products fails to address the efficacy of similar products derived from humans. We used a novel immunodeficient rat carotid injury model in order to determine whether human cells could improve vascular remodelling following acute injury. Methods Human CD34+ cells were separated from peripheral buffy coats using automatic magnetic cell separation. Carotid arterial injury was performed in male Sprague-Dawley nude rats using a 2F Fogarty balloon catheter. Freshly harvested CD34+ cells or saline alone was administered locally for 20 minutes by endoluminal instillation. Structural and functional analysis of the arteries was performed 28 days later. Results Morphometric analysis demonstrated that human CD34+ cell delivery was associated with a significant reduction in intimal formation 4 weeks following balloon injury as compared with saline (I/M ratio 0.79 ± 0.18, and 1.71 ± 0.18 for CD34, and saline-treated vessels, respectively P Conclusion Delivery of human CD34+ cells limits neointima formation and improves arterial reactivity after vascular injury. These studies advance the concept of cell delivery to effect vascular remodeling toward a potential human cellular product.

  16. Generation of electrical power under human skin by subdermal solar cell arrays for implantable bioelectronic devices.

    Science.gov (United States)

    Song, Kwangsun; Han, Jung Hyun; Yang, Hyung Chae; Nam, Kwang Il; Lee, Jongho

    2017-06-15

    Medical electronic implants can significantly improve people's health and quality of life. These implants are typically powered by batteries, which usually have a finite lifetime and therefore must be replaced periodically using surgical procedures. Recently, subdermal solar cells that can generate electricity by absorbing light transmitted through skin have been proposed as a sustainable electricity source to power medical electronic implants in bodies. However, the results to date have been obtained with animal models. To apply the technology to human beings, electrical performance should be characterized using human skin covering the subdermal solar cells. In this paper, we present electrical performance results (up to 9.05mW/cm(2)) of the implantable solar cell array under 59 human skin samples isolated from 10 cadavers. The results indicate that the power densities depend on the thickness and tone of the human skin, e.g., higher power was generated under thinner and brighter skin. The generated power density is high enough to operate currently available medical electronic implants such as pacemakers that require tens of microwatt.

  17. Human amniotic epithelial cells as feeder layer to derive and maintain human embryonic stem cells from poor-quality embryos.

    Science.gov (United States)

    Ávila-González, Daniela; Vega-Hernández, Eva; Regalado-Hernández, Juan Carlos; De la Jara-Díaz, Julio Francisco; García-Castro, Irma Lydia; Molina-Hernández, Anayansi; Moreno-Verduzco, Elsa Romelia; Razo-Aguilera, Guadalupe; Flores-Herrera, Héctor; Portillo, Wendy; Díaz-Martínez, Néstor Emmanuel; García-López, Guadalupe; Díaz, Néstor Fabián

    2015-09-01

    Data from the literature suggest that human embryonic stem cell (hESC) lines used in research do not genetically represent all human populations. The derivation of hESC through conventional methods involve the destruction of viable human embryos, as well the use of mouse embryonic fibroblasts as a feeder layer, which has several drawbacks. We obtained the hESC line (Amicqui-1) from poor-quality (PQ) embryos derived and maintained on human amniotic epithelial cells (hAEC). This line displays a battery of markers of pluripotency and we demonstrated the capacity of these cells to produce derivates of the three germ layers.

  18. Human amniotic epithelial cells as feeder layer to derive and maintain human embryonic stem cells from poor-quality embryos

    Directory of Open Access Journals (Sweden)

    Daniela Ávila-González

    2015-09-01

    Full Text Available Data from the literature suggest that human embryonic stem cell (hESC lines used in research do not genetically represent all human populations. The derivation of hESC through conventional methods involve the destruction of viable human embryos, as well the use of mouse embryonic fibroblasts as a feeder layer, which has several drawbacks. We obtained the hESC line (Amicqui-1 from poor-quality (PQ embryos derived and maintained on human amniotic epithelial cells (hAEC. This line displays a battery of markers of pluripotency and we demonstrated the capacity of these cells to produce derivates of the three germ layers.

  19. Human embryonic stem cells differentiate into functional renal proximal tubular-like cells.

    Science.gov (United States)

    Narayanan, Karthikeyan; Schumacher, Karl M; Tasnim, Farah; Kandasamy, Karthikeyan; Schumacher, Annegret; Ni, Ming; Gao, Shujun; Gopalan, Began; Zink, Daniele; Ying, Jackie Y

    2013-04-01

    Renal cells are used in basic research, disease models, tissue engineering, drug screening, and in vitro toxicology. In order to provide a reliable source of human renal cells, we developed a protocol for the differentiation of human embryonic stem cells into renal epithelial cells. The differentiated stem cells expressed markers characteristic of renal proximal tubular cells and their precursors, whereas markers of other renal cell types were not expressed or expressed at low levels. Marker expression patterns of these differentiated stem cells and in vitro cultivated primary human renal proximal tubular cells were comparable. The differentiated stem cells showed morphological and functional characteristics of renal proximal tubular cells, and generated tubular structures in vitro and in vivo. In addition, the differentiated stem cells contributed in organ cultures for the formation of simple epithelia in the kidney cortex. Bioreactor experiments showed that these cells retained their functional characteristics under conditions as applied in bioartificial kidneys. Thus, our results show that human embryonic stem cells can differentiate into renal proximal tubular-like cells. Our approach would provide a source for human renal proximal tubular cells that are not affected by problems associated with immortalized cell lines or primary cells.

  20. Growth suppressive efficacy of human lak cells against human lung-cancer implanted into scid mice.

    Science.gov (United States)

    Teraoka, S; Kyoizumi, S; Suzuki, T; Yamakido, M; Akiyama, M

    1995-06-01

    The purpose of our study was to determine the efficacy of immunotherapy using human lymphokine activated killer (LAK) cells against a human-lung squamous-cell carcinoma cell line (RERF-LC-AI) implanted into severe combined immunodeficient (SCID) mice. A statistically significant growth suppressive effect on RERF-LC-AI implanted into SCID mice was observed when human LAK cells were administered into the caudal vein of the mice treated with a continuous supply (initiated prior to LAK cells injection) of rIL-2. The human LAK cells stained with PKH 2, a fluorescent dye, for later detection using flow cytometry were administered into the caudal vein of RERF-LC-AI bearing SCID mice; the cells persisted for 7 days in the implanted lung cancer tissue and in the mouse peripheral blood, but for 5 days in the mouse spleen. The number of infiltrated human LAK cells in each tissue increased dose-dependently with the number of injected cells. The results indicate that the antitumor effect most likely occurred during the early implantation period of the human LAK cells. These results demonstrate the applicability of this model to the in vivo study of human lung cancer therapy.

  1. Effects of hydroxyapatite nanoparticles on proliferation and apoptosis of human breast cancer cells (MCF-7)

    Science.gov (United States)

    Meena, Ramovatar; Kesari, Kavindra Kumar; Rani, Madhu; Paulraj, R.

    2012-02-01

    The study aimed to correlate cell proliferation inhibition with oxidative stress and p53 protein expression in cancerous cells. Hydroxyapatite (HAP) (Ca10(PO4)6(OH)2) is the essential component of inorganic composition in human bone. It has been found to have obvious inhibitory function on growth of many kinds of tumor cells and its nanoparticle has stronger anti-cancerous effect than macromolecule microparticles. Human breast cancer cells (MCF-7) were cultured and treated with HAP nanoparticles at various concentrations. Cells viability was detected with MTT colorimetric assay. The morphology of the cancerous cells was performed by transmission electron microscopy and the expression of a cell apoptosis related gene (p53) was determined by ELISA assay and flow cytometry (FCM). The intracellular reactive oxygen species (ROS) level in HAP exposed cells was measured by H2DCFDA staining. DNA damage was measured by single-cell gel electrophoresis assay. The statistical analysis was done by one way ANOVA. The cellular proliferation inhibition rate was significantly ( p Cell apoptotic characters were observed after MCF-7 cells were treated by HAP nanoparticles for 48 h. Moreover, ELISA assay and FCM shows a dose-dependent activation of p53 in MCF-7 cells treated with nanoHAP. These causative factors of the above results may be justified by an overproduction of ROS. In this study, a significant ( p cells was observed. This study shows that HAP inhibits the growth of human breast cancer MCF-7 cells as well as induces cell apoptosis. This study shows that HAP NPs Induce the production of intracellular reactive oxygen species and activate p53, which may be responsible for DNA damage and cell apoptosis.

  2. Use of human pluripotent stem cells to study and treatretinopathies

    Institute of Scientific and Technical Information of China (English)

    Karim Ben M’Barek; Florian Regent; Christelle Monville

    2015-01-01

    Human cell types affected by retinal diseases (such asage-related macular degeneration or retinitis pimentosa)are limited in cell number and of reduced accessibility. As aconsequence, their isolation for in vitro studies of diseasemechanisms or for drug screening efforts is fastidious.Human pluripotent stem cells (hPSCs), either of embryonicorigin or through reprogramming of adult somatic cells,represent a new promising way to generate models ofhuman retinopathies, explore the physiopathologicalmechanisms and develop novel therapeutic strategies.Disease-specific human embryonic stem cells were thefirst source of material to be used to study certain diseasestates. The recent demonstration that human somaticcells, such as fibroblasts or blood cells, can be geneticallyconverted to induce pluripotent stem cells together withthe continuous improvement of methods to differentiatethese cells into disease-affected cellular subtypes opensnew perspectives to model and understand a largenumber of human pathologies, including retinopathies.This review focuses on the added value of hPSCs for thedisease modeling of human retinopathies and the study oftheir molecular pathological mechanisms. We also discussthe recent use of these cells for establishing the validationstudies for therapeutic intervention and for the screeningof large compound libraries to identify candidate drugs.

  3. Characterization of macrophage-like cells in the external layers of human small and large intestine

    DEFF Research Database (Denmark)

    Mikkelsen, H B; Rumessen, J J

    1992-01-01

    -DR-positive (expressing the MHC class-II antigen), in contrast to macrophage-like cells in the subserosa and submucosa. Macrophage-like cells in the external muscle layer were mostly acid phosphatase-negative, and at the electron-microscopic level they were found to have features of macrophages: primary lysosomes, coated...... vesicles and pits. However, very few secondary lysosomes were present. Birbeck granules were not observed. It is concluded that in the external muscle layer of human small and large intestine numerous macrophages of a special type are present. It is discussed whether this cell type plays a role...

  4. Pancreatic hormones are expressed on the surfaces of human and rat islet cells through exocytotic sites

    DEFF Research Database (Denmark)

    Larsson, L I; Hutton, J C; Madsen, O D

    1989-01-01

    . Electron microscopy reveals the labeling to occur at sites of exocytotic granule release, involving the surfaces of extruded granule cores. The surfaces of islet cells were labeled both by polyclonal and monoclonal antibodies, excluding that receptor-interacting, anti-idiotypic hormone antibodies were...... responsible for the staining. Human insulin cells were surface-labeled by monoclonal antibodies recognizing the mature secretory products, insulin and C-peptide but not with monoclonal antibodies specific for proinsulin. Thus, routing of unprocessed preproinsulin to the cell surface may not account...... for these results. It is concluded that the staining reflects interactions between the appropriate antibodies and exocytotic sites of hormone release....

  5. Proteomic Analysis of Human Blastocoel Fluid and Blastocyst Cells

    DEFF Research Database (Denmark)

    Linnert Jensen, Pernille; Beck, Hans Christian; Petersen, Jørgen;

    the cells of the blastocyst are exposed. The ICM is the starting point for the development of undifferentiated human embryonic stem cells (hESCs), which posses the potential to develop into any cell type present in the adult human body [1,2]. This ability makes hESCs a potential source of cells...... for regenerative medicine, such as in the treatment of diabetes, Parkinson’s disease, blindness, and spinal cord injury. In the context of developing regenerative medicine based on hESCs, it remains a challenge to employ safe, xenofree and defined culture conditions. The blastocoel fluid is per se the in vivo......The human blastocyst consists of 100-200 cells that are organized in an outer layer of differentiated trophectoderm (TE) cells lining the blastocyst cavity into which the undifferentiated inner cell mass (ICM) protrudes. The cavity of the blastocyst is filled with blastocoel fluid to which all...

  6. Proteomic Analysis of Human Blastocoel Fluid and Blastocyst Cells

    DEFF Research Database (Denmark)

    Linnert Jensen, Pernille; Beck, Hans Christian; Petersen, Jørgen

    the cells of the blastocyst are exposed. The ICM is the starting point for the development of undifferentiated human embryonic stem cells (hESCs), which posses the potential to develop into any cell type present in the adult human body [1,2]. This ability makes hESCs a potential source of cells......The human blastocyst consists of 100-200 cells that are organized in an outer layer of differentiated trophectoderm (TE) cells lining the blastocyst cavity into which the undifferentiated inner cell mass (ICM) protrudes. The cavity of the blastocyst is filled with blastocoel fluid to which all...... for regenerative medicine, such as in the treatment of diabetes, Parkinson’s disease, blindness, and spinal cord injury. In the context of developing regenerative medicine based on hESCs, it remains a challenge to employ safe, xenofree and defined culture conditions. The blastocoel fluid is per se the in vivo...

  7. Human induced pluripotent stem cells: A disruptive innovation.

    Science.gov (United States)

    De Vos, J; Bouckenheimer, J; Sansac, C; Lemaître, J-M; Assou, S

    2016-01-01

    This year (2016) will mark the 10th anniversary of the discovery of induced pluripotent stem cells (iPSCs). The finding that the transient expression of four transcription factors can radically remodel the epigenome, transcriptome and metabolome of differentiated cells and reprogram them into pluripotent stem cells has been a major and groundbreaking technological innovation. In this review, we discuss the major applications of this technology that we have grouped in nine categories: a model to study cell fate control; a model to study pluripotency; a model to study human development; a model to study human tissue and organ physiology; a model to study genetic diseases in a dish; a tool for cell rejuvenation; a source of cells for drug screening; a source of cells for regenerative medicine; a tool for the production of human organs in animals.

  8. Genome editing: a robust technology for human stem cells.

    Science.gov (United States)

    Chandrasekaran, Arun Pandian; Song, Minjung; Ramakrishna, Suresh

    2017-09-01

    Human pluripotent stem cells comprise induced pluripotent and embryonic stem cells, which have tremendous potential for biological and therapeutic applications. The development of efficient technologies for the targeted genome alteration of stem cells in disease models is a prerequisite for utilizing stem cells to their full potential. Genome editing of stem cells is possible with the help of synthetic nucleases that facilitate site-specific modification of a gene of interest. Recent advances in genome editing techniques have improved the efficiency and speed of the development of stem cells for human disease models. Zinc finger nucleases, transcription activator-like effector nucleases, and clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated system are powerful tools for editing DNA at specific loci. Here, we discuss recent technological advances in genome editing with site-specific nucleases in human stem cells.

  9. Phenotype and functions of memory Tfh cells in human blood.

    Science.gov (United States)

    Schmitt, Nathalie; Bentebibel, Salah-Eddine; Ueno, Hideki

    2014-09-01

    Our understanding of the origin and functions of human blood CXCR5(+) CD4(+) T cells found in human blood has changed dramatically in the past years. These cells are currently considered to represent a circulating memory compartment of T follicular helper (Tfh) lineage cells. Recent studies have shown that blood memory Tfh cells are composed of phenotypically and functionally distinct subsets. Here, we review the current understanding of human blood memory Tfh cells and the subsets within this compartment. We present a strategy to define these subsets based on cell surface profiles. Finally, we discuss how increased understanding of the biology of blood memory Tfh cells may contribute insight into the pathogenesis of autoimmune diseases and the mode of action of vaccines.

  10. Human embryonic stem cell lines derived from the Chinese population

    Institute of Scientific and Technical Information of China (English)

    Zhen Fu FANG; Fan JIN; Hui GAI; Ying CHEN; Li WU; Ai Lian LIU; Bin CHEN; Hui Zhen SHENG

    2005-01-01

    Six human embryonic stem cell lines were established from surplus blastocysts. The cell lines expressed alkaline phosphatase and molecules typical of primate embryonic stem cells, including Oct-4, Nanog, TDGF1, Sox2, EBAF,Thy-1, FGF4, Rex-1, SSEA-3, SSEA-4, TRA-1-60 and TRA-1-81. Five of the six lines formed embryoid bodies that expressed markers of a variety of cell types; four of them formed teratomas with tissue types representative of all three embryonic germ layers. These human embryonic stem cells are capable of producing clones of undifferentiated morphology, and one of them was propagated to become a subline. Human embryonic stem cell lines from the Chinese population should facilitate stem cell research and may be valuable in studies of population genetics and ecology.

  11. An overview of electron acceptors in microbial fuel cells

    DEFF Research Database (Denmark)

    Ucar, Deniz; Zhang, Yifeng; Angelidaki, Irini

    2017-01-01

    as an electron acceptor due to its high oxidation potential and ready availability. Recent studies, however, have begun to assess the use of different electron acceptors because of the (1) diversity of redox potential, (2) needs of alternative and more efficient cathode reaction, and (3) expanding of MFC based...

  12. Exposure to Music Alters Cell Viability and Cell Motility of Human Nonauditory Cells in Culture

    Directory of Open Access Journals (Sweden)

    Nathalia R. Lestard

    2016-01-01

    Full Text Available Although music is part of virtually all cultures in the world, little is known about how it affects us. Since the beginning of this century several studies suggested that the response to music, and to sound in general, is complex and might not be exclusively due to emotion, given that cell types other than auditory hair cells can also directly react to audible sound. The present study was designed to better understand the direct effects of acoustic vibrations, in the form of music, in human cells in culture. Our results suggest that the mechanisms of cell growth arrest and/or cell death induced by acoustic vibrations are similar for auditory and nonauditory cells.

  13. Light microscopic, electron microscopic, and immunohistochemical comparison of Bama minipig (Sus scrofa domestica) and human skin.

    Science.gov (United States)

    Liu, Yu; Chen, Jun-ying; Shang, Hai-tao; Liu, Chang-e; Wang, Yong; Niu, Rong; Wu, Jun; Wei, Hong

    2010-04-01

    Here we sought to evaluate the possibility of using Chinese Bama miniature pig skin as a suitable animal model for human skin. Morphologic features of the skin of Bama miniature pigs resemble those of human skin, including skin layer thickness, development of a superficial vascular system, structure of the dermal-epidermal interface, and extracellular matrix. The characteristics and densities of Langerhans cells, fibroblasts, vascular endothelial cells, and mast cells were similar between Bama pig and human skin. Immunohistochemistry showed that miniature pigs and humans have the same antigenic determinants of human laminin, fibronectin, filaggrin, collagen I, collagen III, collagen IV, and keratin but not CD34, ICAM1, or S100. In addition, collagen type I from Bama miniature pig skin exhibited physicochemical characteristics resembling those of human skin, in regard to HPLC chromatography, UV spectroscopy, amino-acid composition, and SDS-PAGE analysis. Given these results, we concluded that Bama miniature pigs have great potential as a human skin model and for developing dermal substitute materials in wound repair. However, we also observed some disparities between the skin of Bama miniature pigs and humans, including pigment cell distribution, sweat gland types, and others. Therefore, further studies are needed to completely evaluate the effects of these interspecies differences on the actual application of the model.

  14. Radiation response of mesenchymal stem cells derived from bone marrow and human pluripotent stem cells

    OpenAIRE

    Islam, Mohammad S; Stemig, Melissa E.; Takahashi, Yutaka; Hui, Susanta K.

    2014-01-01

    Mesenchymal stem cells (MSCs) isolated from human pluripotent stem cells are comparable with bone marrow-derived MSCs in their function and immunophenotype. The purpose of this exploratory study was comparative evaluation of the radiation responses of mesenchymal stem cells derived from bone marrow- (BMMSCs) and from human embryonic stem cells (hESMSCs). BMMSCs and hESMSCs were irradiated at 0 Gy (control) to 16 Gy using a linear accelerator commonly used for cancer treatment. Cells were harv...

  15. The effects of TSH on human vascular endothelial cells and smooth muscle cells

    Institute of Scientific and Technical Information of China (English)

    田利民

    2014-01-01

    Objective To study the effect of thyroid-stimulating hormone(TSH)on human vascular endothelial cells and smooth muscle cells and to explore the roles of TSH in the development of atherosclerosis.Methods Human vascular endothelial cells and smooth muscle cells were cultured in vitro.MTT method was used to assay the effect of TSH on cell viability.Real-time PCR was used

  16. Temperature and 8 MeV electron irradiation effects on GaAs solar cells

    Indian Academy of Sciences (India)

    Asha Rao; Sheeja Krishnan; Ganesh Sajeev; K Siddappa

    2010-06-01

    GaAs solar cells hold the record for the highest single band-gap cell efficiency. Successful application of these cells in advanced space-borne systems demand characterization of cell properties like dark current under different ambient conditions and the stability of the cells against particle irradiation in space. In this paper, the results of the studies carried out on the effect of 8 MeV electron irradiation on the electrical properties of GaAs solar cells are presented. The – (current–voltage) characteristics of the cells under dark and AM1.5 illumination condition are studied and 8 MeV electron irradiation was carried out on the cells where they were exposed to graded doses of electrons from 1 to 100 kGy. The devices were also characterized using capacitance measurements at various frequencies before and after irradiation. The effect of electron irradiation on the solar cell parameters was studied. It is found that only small changes were observed in the GaAs solar cell parameters up to an electron dose of 100 kGy, exhibiting good tolerance for electrons of 8 MeV energy.

  17. Applied Developmental Biology: Making Human Pancreatic Beta Cells for Diabetics.

    Science.gov (United States)

    Melton, Douglas A

    2016-01-01

    Understanding the genes and signaling pathways that determine the differentiation and fate of a cell is a central goal of developmental biology. Using that information to gain mastery over the fates of cells presents new approaches to cell transplantation and drug discovery for human diseases including diabetes. © 2016 Elsevier Inc. All rights reserved.

  18. Establishment of human embryonic stem cell line from gamete donors

    Institute of Scientific and Technical Information of China (English)

    LI Tao; ZHOU Can-quan; MAI Qing-yun; ZHUANG Guang-lun

    2005-01-01

    Background Human embryonic stem (HES) cell derived from human blastocyst can be propagated indefinitely in the primitive undifferentiated state while remaining pluripotent. It has exciting potential in human developmental biology, drug discovery, and transplantation medicine. But there are insufficient HES cell lines for further study. Methods Three oocyte donors were studied, and 3 in vitro fertilization (IVF) cycles were carried out to get blastocysts for the establishment of HES cell line. Isolated from blastocysts immunosurgically, inner cell mass (ICM) was cultured and propagated on mouse embryonic fibroblasts (MEFs). Once established, morphology, cell surface markers, karyotype and differentiating ability of the cell line were thoroughly analyzed.Results Four ICMs from 7 blastocysts were cultured on MEFs. After culture, one cell line (cHES-1) was established and met the criteria for defining human pluripotent stem cells including a series of markers used to identify pluripotent stem cells, morphological similarity to primate embryonic stem cells and HES reported else where. Normal and stable karyotype maintained over 60 passages, and demonstrated ability to differentiate into a wide variety of cell types.Conclusions HES cell lines can be established from gamete donors at a relatively highly efficient rate. The establishment will exert a widespread impact on biomedical research.

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

    Science.gov (United States)

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

    2011-09-01

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

  20. The regulated secretory pathway in CD4(+ T cells contributes to human immunodeficiency virus type-1 cell-to-cell spread at the virological synapse.

    Directory of Open Access Journals (Sweden)

    Clare Jolly

    2011-09-01

    Full Text Available Direct cell-cell spread of Human Immunodeficiency Virus type-1 (HIV-1 at the virological synapse (VS is an efficient mode of dissemination between CD4(+ T cells but the mechanisms by which HIV-1 proteins are directed towards intercellular contacts is unclear. We have used confocal microscopy and electron tomography coupled with functional virology and cell biology of primary CD4(+ T cells from normal individuals and patients with Chediak-Higashi Syndrome and report that the HIV-1 VS displays a regulated secretion phenotype that shares features with polarized secretion at the T cell immunological synapse (IS. Cell-cell contact at the VS re-orientates the microtubule organizing center (MTOC and organelles within the HIV-1-infected T cell towards the engaged target T cell, concomitant with polarization of viral proteins. Directed secretion of proteins at the T cell IS requires specialized organelles termed secretory lysosomes (SL and we show that the HIV-1 envelope glycoprotein (Env localizes with CTLA-4 and FasL in SL-related compartments and at the VS. Finally, CD4(+ T cells that are disabled for regulated secretion are less able to support productive cell-to-cell HIV-1 spread. We propose that HIV-1 hijacks the regulated secretory pathway of CD4(+ T cells to enhance its dissemination.

  1. The Regulated Secretory Pathway in CD4+ T cells Contributes to Human Immunodeficiency Virus Type-1 Cell-to-Cell Spread at the Virological Synapse

    Science.gov (United States)

    Jolly, Clare; Welsch, Sonja; Michor, Stefanie; Sattentau, Quentin J.

    2011-01-01

    Direct cell-cell spread of Human Immunodeficiency Virus type-1 (HIV-1) at the virological synapse (VS) is an efficient mode of dissemination between CD4+ T cells but the mechanisms by which HIV-1 proteins are directed towards intercellular contacts is unclear. We have used confocal microscopy and electron tomography coupled with functional virology and cell biology of primary CD4+ T cells from normal individuals and patients with Chediak-Higashi Syndrome and report that the HIV-1 VS displays a regulated secretion phenotype that shares features with polarized secretion at the T cell immunological synapse (IS). Cell-cell contact at the VS re-orientates the microtubule organizing center (MTOC) and organelles within the HIV-1-infected T cell towards the engaged target T cell, concomitant with polarization of viral proteins. Directed secretion of proteins at the T cell IS requires specialized organelles termed secretory lysosomes (SL) and we show that the HIV-1 envelope glycoprotein (Env) localizes with CTLA-4 and FasL in SL-related compartments and at the VS. Finally, CD4+ T cells that are disabled for regulated secretion are less able to support productive cell-to-cell HIV-1 spread. We propose that HIV-1 hijacks the regulated secretory pathway of CD4+ T cells to enhance its dissemination. PMID:21909273

  2. Stepwise development of MAIT cells in mouse and human.

    Directory of Open Access Journals (Sweden)

    Emmanuel Martin

    2009-03-01

    Full Text Available Mucosal-associated invariant T (MAIT cells display two evolutionarily conserved features: an invariant T cell receptor (TCRalpha (iTCRalpha chain and restriction by the nonpolymorphic class Ib major histocompatibility complex (MHC molecule, MHC-related molecule 1 (MR1. MR1 expression on thymus epithelial cells is not necessary for MAIT cell development but their accumulation in the gut requires MR1 expressing B cells and commensal flora. MAIT cell development is poorly known, as these cells have not been found in the thymus so far. Herein, complementary human and mouse experiments using an anti-humanValpha7.2 antibody and MAIT cell-specific iTCRalpha and TCRbeta transgenic mice in different genetic backgrounds show that MAIT cell development is a stepwise process, with an intra-thymic selection followed by peripheral expansion. Mouse MAIT cells are selected in an MR1-dependent manner both in fetal thymic organ culture and in double iTCRalpha and TCRbeta transgenic RAG knockout mice. In the latter mice, MAIT cells do not expand in the periphery unless B cells are added back by adoptive transfer, showing that B cells are not required for the initial thymic selection step but for the peripheral accumulation. In humans, contrary to natural killer T (NKT cells, MAIT cells display a naïve phenotype in the thymus as well as in cord blood where they are in low numbers. After birth, MAIT cells acquire a memory phenotype and expand dramatically, up to 1%-4% of blood T cells. Finally, in contrast with NKT cells, human MAIT cell development is independent of the molecular adaptor SAP. Interestingly, mouse MAIT cells display a naïve phenotype and do not express the ZBTB16 transcription factor, which, in contrast, is expressed by NKT cells and the memory human MAIT cells found in the periphery after birth. In conclusion, MAIT cells are selected by MR1 in the thymus on a non-B non-T hematopoietic cell, and acquire a memory phenotype and expand in the

  3. Identification of Interstitial Cajal-Like Cells in the Human Thoracic Duct

    DEFF Research Database (Denmark)

    Briggs Boedtkjer, Donna; Rumessen, Jüri; Baandrup, Ulrik;

    2012-01-01

    Interstitial Cajal-like cells (ICLCs) are speculated to be pacemakers in smooth muscle tissues. While the human thoracic duct (TD) is spontaneously active, the origin of this activity is unknown. We hypothesized that ICLCs could be present in the TD and using histological techniques, immunohistoc...... spindle shapes. Confocal imaging with calcium-dependent fluorophores corroborated cell morphology and localization observed in fixed tissues. Lymphatic ICLCs thus constitute a significant cell type of the human TD and physically interact with lymphatic SMCs......., immunohistochemistry and immunofluorescence we have investigated the presence of ICLCs, protein markers for ICLCs and the cellular morphology of the human TD. Transmission electron microscopy was employed to investigate ultrastructure. Methylene blue staining, calcium-dependent fluorophores and confocal microscopy...

  4. Quantitative detection of gold nanoparticles on individual, unstained cancer cells by scanning electron microscopy.

    Science.gov (United States)

    Hartsuiker, L; VAN Es, P; Petersen, W; VAN Leeuwen, T G; Terstappen, L W M M; Otto, C

    2011-11-01

    Gold nanoparticles are rapidly emerging for use in biomedical applications. Characterization of the interaction and delivery of nanoparticles to cells through microscopy is important. Scanning electron microscopes have the intrinsic resolution to visualize gold nanoparticles on cells. A novel sample preparation protocol was developed to enable imaging of cells and gold nanoparticles with a conventional below lens scanning electron microscopes. The negative influence of 'charging' on the quality of scanning electron microscopes' images could be limited by deposition of biological cells on a conductive (gold) surface. The novel protocol enabled high-resolution scanning electron microscopes' imaging of small clusters and individual gold nanoparticles on uncoated cell surfaces. Gold nanoparticles could be counted on cancer cells with automated routines.

  5. Human stem cells and articular cartilage regeneration.

    Science.gov (United States)

    Inui, Atsuyuki; Iwakura, Takashi; Reddi, A Hari

    2012-11-05

    The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES) cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS) cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  6. Human Stem Cells and Articular Cartilage Regeneration

    Directory of Open Access Journals (Sweden)

    A. Hari Reddi

    2012-11-01

    Full Text Available  The regeneration of articular cartilage damaged due to trauma and posttraumatic osteoarthritis is an unmet medical need. Current approaches to regeneration and tissue engineering of articular cartilage include the use of chondrocytes, stem cells, scaffolds and signals, including morphogens and growth factors. Stem cells, as a source of cells for articular cartilage regeneration, are a critical factor for articular cartilage regeneration. This is because articular cartilage tissue has a low cell turnover and does not heal spontaneously. Adult stem cells have been isolated from various tissues, such as bone marrow, adipose, synovial tissue, muscle and periosteum. Signals of the transforming growth factor beta superfamily play critical roles in chondrogenesis. However, adult stem cells derived from various tissues tend to differ in their chondrogenic potential. Pluripotent stem cells have unlimited proliferative capacity compared to adult stem cells. Chondrogenesis from embryonic stem (ES cells has been studied for more than a decade. However, establishment of ES cells requires embryos and leads to ethical issues for clinical applications. Induced pluripotent stem (iPS cells are generated by cellular reprogramming of adult cells by transcription factors. Although iPS cells have chondrogenic potential, optimization, generation and differentiation toward articular chondrocytes are currently under intense investigation.

  7. Cell-level battery charge/discharge protection system. [electronic control techniques

    Science.gov (United States)

    Donovan, R. L.; Imamura, M. S.

    1977-01-01

    The paper describes three design approaches to individual cell monitoring and control for sealed secondary battery cells. One technique involves a modular strap-on single cell protector which contains all the electronics required for monitoring cell voltage, responding to external commands, and forming a bypass circuit for the cell. A second technique, the multiplexed cell protector, uses common circuitry to monitor and control each cell in a battery pack. The third technique, the computerized cell protector, by replacing the hard-wired logic of the multiplexed cell protector with a microprocessor, achieves greatest control flexibility and inherent computational capability with a minimum parts count implementation.

  8. Growth-stimulatory effect of resveratrol in human cancer cells.

    Science.gov (United States)

    Fukui, Masayuki; Yamabe, Noriko; Kang, Ki Sung; Zhu, Bao Ting

    2010-08-01

    Earlier studies have shown that resveratrol could induce death in several human cancer cell lines in culture. Here we report our observation that resveratrol can also promote the growth of certain human cancer cells when they are grown either in culture or in athymic nude mice as xenografts. At relatively low concentrations (cells, but this effect was not observed in several other human cell lines tested. Analysis of cell signaling molecules showed that resveratrol induced the activation of JNK, p38, Akt, and NF-kappaB signaling pathways in these cells. Further analysis using pharmacological inhibitors showed that only the NF-kappaB inhibitor (BAY11-7082) abrogated the growth-stimulatory effect of resveratrol in cultured cells. In athymic nude mice, resveratrol at 16.5 mg/kg body weight enhanced the growth of MDA-MB-435s xenografts compared to the control group, while resveratrol at the 33 mg/kg body weight dose did not have a similar effect. Additional analyses confirmed that resveratrol stimulated cancer cell growth in vivo through activation of the NF-kappaB signaling pathway. Taken together, these observations suggest that resveratrol at low concentrations could stimulate the growth of certain types of human cancer cells in vivo. This cell type-specific mitogenic effect of resveratrol may also partly contribute to the procarcinogenic effect of alcohol consumption (rich in resveratrol) in the development of certain human cancers.

  9. Development of biomimetic nanocomposites as bone extracellular matrix for human osteoblastic cells.

    Science.gov (United States)

    Bhowmick, Arundhati; Mitra, Tapas; Gnanamani, Arumugam; Das, Manas; Kundu, Patit Paban

    2016-05-05

    Here, we have developed biomimetic nanocomposites containing chitosan, poly(vinyl alcohol) and nano-hydroxyapatite-zinc oxide as bone extracellular matrix for human osteoblastic cells and characterized by Fourier transform infrared spectroscopy, powder X-ray diffraction. Scanning electron microscopy images revealed interconnected macroporous structures. Moreover, in this study, the problem related to fabricating a porous composite with good mechanical strength has been resolved by incorporating 5wt% of nano-hydroxyapatite-zinc oxide into chitosan-poly(vinyl alcohol) matrix; the present composite showed high tensile strength (20.25MPa) while maintaining appreciable porosity (65.25%). These values are similar to human cancellous bone. These nanocomposites also showed superior water uptake, antimicrobial and biodegradable properties than the previously reported results. Compatibility with human blood and pH was observed, indicating nontoxicity of these materials to the human body. Moreover, proliferation of osteoblastic MG-63 cells onto the nanocomposites was also observed without having any negative effect.

  10. Abnormal number cell division of human thyroid anaplastic carcinoma cell line, SW 1736

    Directory of Open Access Journals (Sweden)

    Keiichi Ikeda

    2015-12-01

    Full Text Available Cell division, during which a mother cell usually divides into two daughter cells during one cell cycle, is the most important physiological event of cell biology. We observed one-to-four cell division during imaging of live SW1736 human thyroid anaplastic carcinoma cells transfected with a plasmid expressing the hybrid protein of green fluorescent protein and histone 2B (plasmid eGFP-H2B. Analysis of the images revealed a mother cell divided into four daughter cells. And one of the abnormally divided daughter cells subsequently formed a dinucleate cell.

  11. Scanning electron microscopy of the human endolymphatic sac: a preliminary report.

    Science.gov (United States)

    Galey, F R; House, W F

    1980-04-01

    Scanning electron microscopy has been used to examine and compare one normal endolymphatic sac with one endolymphatic sac from a patient with Meniere's disease. The surgical procedure for obtaining these specimens and their preparation for scanning electron microscopy are described. The luminal surface of the rugose portion of both specimens was lined with two populations of epithelial cells: one with a dome-shaped apical surface, the other with a flattened polygonal surface. The surface of dome-shaped cells in both specimens was covered with microvilli. Neither specimen had observable loss of epithelial integrity or fibrosis.

  12. Materials and optimized designs for human-machine interfaces via epidermal electronics.

    Science.gov (United States)

    Jeong, Jae-Woong; Yeo, Woon-Hong; Akhtar, Aadeel; Norton, James J S; Kwack, Young-Jin; Li, Shuo; Jung, Sung-Young; Su, Yewang; Lee, Woosik; Xia, Jing; Cheng, Huanyu; Huang, Yonggang; Choi, Woon-Seop; Bretl, Timothy; Rogers, John A

    2013-12-17

    Thin, soft, and elastic electronics with physical properties well matched to the epidermis can be conformally and robustly integrated with the skin. Materials and optimized designs for such devices are presented for surface electromyography (sEMG). The findings enable sEMG from wide ranging areas of the body. The measurements have quality sufficient for advanced forms of human-machine interface.

  13. Localising versus standardising electronic human resource management: complexities and tensions between HRM and IT departments

    NARCIS (Netherlands)

    Tate, Mary; Furtmueller, E.; Wilderom, C.P.M.

    2013-01-01

    In this paper, we provide an analysis of the complexities involved during global e-HRM (Electronic Human Resource Management) implementation. We present findings from a case study on the challenge of global integration versus local responsiveness of e-HRM systems. We take a local site lens, analysin

  14. Proteins differentially expressed in human beta-cells-enriched pancreatic islet cultures and human insulinomas

    DEFF Research Database (Denmark)

    Terra, Letícia F; Teixeira, Priscila C; Wailemann, Rosangela A M

    2013-01-01

    In view of the great demand for human beta-cells for physiological and medical studies, we generated cell lines derived from human insulinomas which secrete insulin, C-peptide and express neuroendocrine and islet markers. In this study, we set out to characterize their proteomes, comparing them t...

  15. Human CD8+ T cells mediate protective immunity induced by a human malaria vaccine in human immune system mice.

    Science.gov (United States)

    Li, Xiangming; Huang, Jing; Zhang, Min; Funakoshi, Ryota; Sheetij, Dutta; Spaccapelo, Roberta; Crisanti, Andrea; Nussenzweig, Victor; Nussenzweig, Ruth S; Tsuji, Moriya

    2016-08-31

    A number of studies have shown that CD8+ T cells mediate protective anti-malaria immunity in a mouse model. However, whether human CD8+ T cells play a role in protection against malaria remains unknown. We recently established human immune system (HIS) mice harboring functional human CD8+ T cells (HIS-CD8 mice) by transduction with HLA-A∗0201 and certain human cytokines using recombinant adeno-associated virus-based gene transfer technologies. These HIS-CD8 mice mount a potent, antigen-specific HLA-A∗0201-restricted human CD8+ T-cell response upon immunization with a recombinant adenovirus expressing a human malaria antigen, the Plasmodium falciparum circumsporozoite protein (PfCSP), termed AdPfCSP. In the present study, we challenged AdPfCSP-immunized HIS-CD8 mice with transgenic Plasmodium berghei sporozoites expressing full-length PfCSP and found that AdPfCSP-immunized (but not naïve) mice were protected against subsequent malaria challenge. The level of the HLA-A∗0201-restricted, PfCSP-specific human CD8+ T-cell response was closely correlated with the level of malaria protection. Furthermore, depletion of human CD8+ T cells from AdPfCSP-immunized HIS-CD8 mice almost completely abolished the anti-malaria immune response. Taken together, our data show that human CD8+ T cells mediate protective anti-malaria immunity in vivo.

  16. Isolation, Culture, and Imaging of Human Fetal Pancreatic Cell Clusters

    Science.gov (United States)

    Lopez, Ana D.; Kayali, Ayse G.; Hayek, Alberto; King, Charles C.

    2014-01-01

    For almost 30 years, scientists have demonstrated that human fetal ICCs transplanted under the kidney capsule of nude mice matured into functioning endocrine cells, as evidenced by a significant increase in circulating human C-peptide following glucose stimulation1-9. However in vitro, genesis of insulin producing cells from human fetal ICCs is low10; results reminiscent of recent experiments performed with human embryonic stem cells (hESC), a renewable source of cells that hold great promise as a potential therapeutic treatment for type 1 diabetes. Like ICCs, transplantation of partially differentiated hESC generate glucose responsive, insulin producing cells, but in vitro genesis of insulin producing cells from hESC is much less robust11-17. A complete understanding of the factors that influence the growth and differentiation of endocrine precursor cells will likely require data generated from both ICCs and hESC. While a number of protocols exist to generate insulin producing cells from hESC in vitro11-22, far fewer exist for ICCs10,23,24. Part of that discrepancy likely comes from the difficulty of working with human fetal pancreas. Towards that end, we have continued to build upon existing methods to isolate fetal islets from human pancreases with gestational ages ranging from 12 to 23 weeks, grow the cells as a monolayer or in suspension, and image for cell proliferation, pancreatic markers and human hormones including glucagon and C-peptide. ICCs generated by the protocol described below result in C-peptide release after transplantation under the kidney capsule of nude mice that are similar to C-peptide levels obtained by transplantation of fresh tissue6. Although the examples presented here focus upon the pancreatic endoderm proliferation and β cell genesis, the protocol can be employed to study other aspects of pancreatic development, including exocrine, ductal, and other hormone producing cells. PMID:24895054

  17. Isolation, culture, and imaging of human fetal pancreatic cell clusters.

    Science.gov (United States)

    Lopez, Ana D; Kayali, Ayse G; Hayek, Alberto; King, Charles C

    2014-05-18

    For almost 30 years, scientists have demonstrated that human fetal ICCs transplanted under the kidney capsule of nude mice matured into functioning endocrine cells, as evidenced by a significant increase in circulating human C-peptide following glucose stimulation(1-9). However in vitro, genesis of insulin producing cells from human fetal ICCs is low(10); results reminiscent of recent experiments performed with human embryonic stem cells (hESC), a renewable source of cells that hold great promise as a potential therapeutic treatment for type 1 diabetes. Like ICCs, transplantation of partially differentiated hESC generate glucose responsive, insulin producing cells, but in vitro genesis of insulin producing cells from hESC is much less robust(11-17). A complete understanding of the factors that influence the growth and differentiation of endocrine precursor cells will likely require data generated from both ICCs and hESC. While a number of protocols exist to generate insulin producing cells from hESC in vitro(11-22), far fewer exist for ICCs(10,23,24). Part of that discrepancy likely comes from the difficulty of working with human fetal pancreas. Towards that end, we have continued to build upon existing methods to isolate fetal islets from human pancreases with gestational ages ranging from 12 to 23 weeks, grow the cells as a monolayer or in suspension, and image for cell proliferation, pancreatic markers and human hormones including glucagon and C-peptide. ICCs generated by the protocol described below result in C-peptide release after transplantation under the kidney capsule of nude mice that are similar to C-peptide levels obtained by transplantation of fresh tissue(6). Although the examples presented here focus upon the pancreatic endoderm proliferation and β cell genesis, the protocol can be employed to study other aspects of pancreatic development, including exocrine, ductal, and other hormone producing cells.

  18. Human pituitary and placental hormones control human insulin-like growth factor II secretion in human granulosa cells

    Energy Technology Data Exchange (ETDEWEB)

    Ramasharma, K.; Li, C.H.

    1987-05-01

    Human granulosa cells cultured with calf serum actively proliferated for 18-20 generations and secreted progesterone into the medium; progesterone levels appeared to decline with increase in generation number. Cells cultured under serum-free conditions secreted significant amounts of progesterone and insulin-like growth factor II (IGF-II). The progesterone secretion was enhanced by the addition of human follitropin, lutropin, and chorionic gonadotropin but not by growth hormone. These cells, when challenged to varying concentrations of human growth hormone, human chorionic somatomammotropin, human prolactin, chorionic gonadotropin, follitropin, and lutropin, secreted IGF-II into the medium as measured by specific IGF-II RIA. Among these human hormones, chorionic gonadotropin, follitropin, and lutropin were most effective in inducing IGF-II secretion from these cells. When synthetic lutropin-releasing hormone and ..cap alpha..-inhibin-92 were tested, only lutropin-releasing hormone was effective in releasing IGF-II. The results described suggest that cultured human granulosa cells can proliferate and actively secrete progesterone and IGF-II into the medium. IGF-II production in human granulosa cells was influenced by a multi-hormonal complex including human growth hormone, human chorionic somatomammotropin, and prolactin.

  19. Earthing: Health Implications of Reconnecting the Human Body to the Earth's Surface Electrons

    Directory of Open Access Journals (Sweden)

    Gaétan Chevalier

    2012-01-01

    Full Text Available Environmental medicine generally addresses environmental factors with a negative impact on human health. However, emerging scientific research has revealed a surprisingly positive and overlooked environmental factor on health: direct physical contact with the vast supply of electrons on the surface of the Earth. Modern lifestyle separates humans from such contact. The research suggests that this disconnect may be a major contributor to physiological dysfunction and unwellness. Reconnection with the Earth's electrons has been found to promote intriguing physiological changes and subjective reports of well-being. Earthing (or grounding refers to the discovery of benefits—including better sleep and reduced pain—from walking barefoot outside or sitting, working, or sleeping indoors connected to conductive systems that transfer the Earth's electrons from the ground into the body. This paper reviews the earthing research and the potential of earthing as a simple and easily accessed global modality of significant clinical importance.

  20. Tactile-direction-sensitive and stretchable electronic skins based on human-skin-inspired interlocked microstructures.

    Science.gov (United States)

    Park, Jonghwa; Lee, Youngoh; Hong, Jaehyung; Lee, Youngsu; Ha, Minjeong; Jung, Youngdo; Lim, Hyuneui; Kim, Sung Youb; Ko, Hyunhyub

    2014-12-23

    Stretchable electronic skins with multidirectional force-sensing capabilities are of great importance in robotics, prosthetics, and rehabilitation devices. Inspired by the interlocked microstructures found in epidermal-dermal ridges in human skin, piezoresistive interlocked microdome arrays are employed for stress-direction-sensitive, stretchable electronic skins. Here we show that these arrays possess highly sensitive detection capability of various mechanical stimuli including normal, shear, stretching, bending, and twisting forces. Furthermore, the unique geometry of interlocked microdome arrays enables the differentiation of various mechanical stimuli because the arrays exhibit different levels of deformation depending on the direction of applied forces, thus providing different sensory output patterns. In addition, we show that the electronic skins attached on human skin in the arm and wrist areas are able to distinguish various mechanical stimuli applied in different directions and can selectively monitor different intensities and directions of air flows and vibrations.

  1. 3D reconstruction of VZV infected cell nuclei and PML nuclear cages by serial section array scanning electron microscopy and electron tomography.

    Directory of Open Access Journals (Sweden)

    Mike Reichelt

    Full Text Available Varicella-zoster virus (VZV is a human alphaherpesvirus that causes varicella (chickenpox and herpes zoster (shingles. Like all herpesviruses, the VZV DNA genome is replicated in the nucleus and packaged into nucleocapsids that must egress across the nuclear membrane for incorporation into virus particles in the cytoplasm. Our recent work showed that VZV nucleocapsids are sequestered in nuclear cages formed from promyelocytic leukemia protein (PML in vitro and in human dorsal root ganglia and skin xenografts in vivo. We sought a method to determine the three-dimensional (3D distribution of nucleocapsids in the nuclei of herpesvirus-infected cells as well as the 3D shape, volume and ultrastructure of these unique PML subnuclear domains. Here we report the development of a novel 3D imaging and reconstruction strategy that we term Serial Section Array-Scanning Electron Microscopy (SSA-SEM and its application to the analysis of VZV-infected cells and these nuclear PML cages. We show that SSA-SEM permits large volume imaging and 3D reconstruction at a resolution sufficient to localize, count and distinguish different types of VZV nucleocapsids and to visualize complete PML cages. This method allowed a quantitative determination of how many nucleocapsids can be sequestered within individual PML cages (sequestration capacity, what proportion of nucleocapsids are entrapped in single nuclei (sequestration efficiency and revealed the ultrastructural detail of the PML cages. More than 98% of all nucleocapsids in reconstructed nuclear volumes were contained in PML cages and single PML cages sequestered up to 2,780 nucleocapsids, which were shown by electron tomography to be embedded and cross-linked by an filamentous electron-dense meshwork within these unique subnuclear domains. This SSA-SEM analysis extends our recent characterization of PML cages and provides a proof of concept for this new strategy to investigate events during virion assembly at the

  2. 3D Reconstruction of VZV Infected Cell Nuclei and PML Nuclear Cages by Serial Section Array Scanning Electron Microscopy and Electron Tomography

    Science.gov (United States)

    Reichelt, Mike; Joubert, Lydia; Perrino, John; Koh, Ai Leen; Phanwar, Ibanri; Arvin, Ann M.

    2012-01-01

    Varicella-zoster virus (VZV) is a human alphaherpesvirus that causes varicella (chickenpox) and herpes zoster (shingles). Like all herpesviruses, the VZV DNA genome is replicated in the nucleus and packaged into nucleocapsids that must egress across the nuclear membrane for incorporation into virus particles in the cytoplasm. Our recent work showed that VZV nucleocapsids are sequestered in nuclear cages formed from promyelocytic leukemia protein (PML) in vitro and in human dorsal root ganglia and skin xenografts in vivo. We sought a method to determine the three-dimensional (3D) distribution of nucleocapsids in the nuclei of herpesvirus-infected cells as well as the 3D shape, volume and ultrastructure of these unique PML subnuclear domains. Here we report the development of a novel 3D imaging and reconstruction strategy that we term Serial Section Array-Scanning Electron Microscopy (SSA-SEM) and its application to the analysis of VZV-infected cells and these nuclear PML cages. We show that SSA-SEM permits large volume imaging and 3D reconstruction at a resolution sufficient to localize, count and distinguish different types of VZV nucleocapsids and to visualize complete PML cages. This method allowed a quantitative determination of how many nucleocapsids can be sequestered within individual PML cages (sequestration capacity), what proportion of nucleocapsids are entrapped in single nuclei (sequestration efficiency) and revealed the ultrastructural detail of the PML cages. More than 98% of all nucleocapsids in reconstructed nuclear volumes were contained in PML cages and single PML cages sequestered up to 2,780 nucleocapsids, which were shown by electron tomography to be embedded and cross-linked by an filamentous electron-dense meshwork within these unique subnuclear domains. This SSA-SEM analysis extends our recent characterization of PML cages and provides a proof of concept for this new strategy to investigate events during virion assembly at the single cell

  3. Erythroid differentiation of human induced pluripotent stem cells is independent of donor cell type of origin

    OpenAIRE

    2015-01-01

    Epigenetic memory in induced pluripotent stem cells, which is related to the somatic cell type of origin of the stem cells, might lead to variations in the differentiation capacities of the pluripotent stem cells. In this context, induced pluripotent stem cells from human CD34+ hematopoietic stem cells might be more suitable for hematopoietic differentiation than the commonly used fibroblast-derived induced pluripotent stem cells. To investigate the influence of an epigenetic memory on the ex...

  4. Generation and application of human iPS cells

    Institute of Scientific and Technical Information of China (English)

    CUI Ghun; RAO LingJun; CHENG LinZhao; XIAO Lei

    2009-01-01

    Human embryonic stem (ES) cells are capable of unlimited proliferation and maintenance of pluripo-tency in vitro; these properties may lead to potential applications in regenerative medicine.However,immune rejection hampers the allogenic application of human ES cells.Over-expression of several specific transcription factors has been used to reprogram human adult cells into induced pluripotent stem (iPS) cells,which are similar to hESCs in many aspects.The iPS technique makes it possible to produce patient-specific pluripotent stem cells for transplantation therapy without immune rejection.However,some challenges remain,including viral vector integration into the genome,the existence of exogenous oncogenic factors,and low induction efficiency.Here,we review recent advances in human iPS methodology,as well as remaining challenges and its potential applications.

  5. Insulin-producing cells from adult human bone marrow mesenchymal stem cells control streptozotocin-induced diabetes in nude mice.

    Science.gov (United States)

    Gabr, Mahmoud M; Zakaria, Mahmoud M; Refaie, Ayman F; Ismail, Amani M; Abou-El-Mahasen, Mona A; Ashamallah, Sylvia A; Khater, Sherry M; El-Halawani, Sawsan M; Ibrahim, Rana Y; Uin, Gan Shu; Kloc, Malgorzata; Calne, Roy Y; Ghoneim, Mohamed A

    2013-01-01

    Harvesting, expansion, and directed differentiation of human bone marrow-derived mesenchymal stem cells (BM-MSCs) could provide an autologous source of surrogate β-cells that would alleviate the limitations of availability and/or allogenic rejection following pancreatic or islet transplantation. Bone marrow cells were obtained from three adult type 2 diabetic volunteers and three nondiabetic donors. After 3 days in culture, adherent MSCs were expanded for two passages. At passage 3, differentiation was carried out in a three-staged procedure. Cells were cultured in a glucose-rich medium containing several activation and growth factors. Cells were evaluated in vitro by flow cytometry, immunolabeling, RT-PCR, and human insulin and c-peptide release in responses to increasing glucose concentrations. One thousand cell clusters were inserted under the renal capsule of diabetic nude mice followed by monitoring of their diabetic status. At the end of differentiation, ∼5-10% of cells were immunofluorescent for insulin, c-peptide or glucagon; insulin, and c-peptide were coexpressed. Nanogold immunolabeling for electron microscopy demonstrated the presence of c-peptide in the rough endoplasmic reticulum. Insulin-producing cells (IPCs) expressed transcription factors and genes of pancreatic hormones similar to those expressed by pancreatic islets. There was a stepwise increase in human insulin and c-peptide release by IPCs in response to increasing glucose concentrations. Transplantation of IPCs into nude diabetic mice resulted in control of their diabetic status for 3 months. The sera of IPC-transplanted mice contained human insulin and c-peptide but negligible levels of mouse insulin. When the IPC-bearing kidneys were removed, rapid return of diabetic state was noted. BM-MSCs from diabetic and nondiabetic human subjects could be differentiated without genetic manipulation to form IPCs that, when transplanted, could maintain euglycemia in diabetic mice for 3 months

  6. Human epithelial cells exposed to functionalized multiwalled carbon nanotubes: interactions and cell surface modifications.

    Science.gov (United States)

    Fanizza, C; Casciardi, S; Incoronato, F; Cavallo, D; Ursini, C L; Ciervo, A; Maiello, R; Fresegna, A M; Marcelloni, A M; Lega, D; Alvino, A; Baiguera, S

    2015-09-01

    With the expansion of the production and applications of multiwalled carbon nanotubes (MWCNTs) in several industrial and science branches, the potential adverse effects on human health have attracted attention. Numerous studies have been conducted to evaluate how chemical functionalization may affect MWCNT effects; however, controversial data have been reported, showing either increased or reduced toxicity. In particular, the impact of carboxylation on MWCNT cytotoxicity is far from being completely understood. The aim of this work was the evaluation of the modifications induced by carboxylated-MWCNTs (MWCNTs-COOH) on cell surface and the study of cell-MWCNT-COOH interactions by means of field emission scanning electron microscope (FESEM). Human pulmonary epithelial cells (A549) were incubated with MWCNTs-COOH for different exposure times and concentrations (10 μg/mL for 1, 2, 4 h; 5, 10, 20 μg/mL for 24 h). At short incubation time, MWCNTs-COOH were easily observed associated with plasma membrane and in contact with microvilli. After 24 h exposure, FESEM analysis revealed that MWCNTs-COOH induced evident changes in the cellular surface in comparison to control cells: treated cells showed blebs, holes and a depletion of the microvilli density in association with structure modifications, such as widening and/or lengthening. In particular, an increase of cells showing holes and microvilli structure alterations was observed at 20 μg/mL concentration. FESEM analysis showed nanotube agglomerates, of different sizes, entering into the cell with two different mechanisms: inward bending of the membrane followed by nanotube sinking, and nanotube internalization directly through holes. The observed morphological microvilli modifications, induced by MWCNTs-COOH, could affect epithelial functions, such as the control of surfactant production and secretion, leading to pathological conditions, such as alveolar proteinosis. More detailed studies will be, however, necessary to

  7. Effect of Human Cytomegalovirus Infection on Nerve Growth Factor Expression in Human Glioma U251 Cells

    Institute of Scientific and Technical Information of China (English)

    HAI-TAO WANG; BIN WANG; ZHI-JUN LIU; ZHI-QIANG BAI; LING LI; HAI-YAN LIU; DONG-MENG QIAN; ZHI-YONG YAN; XU-XIA SONG

    2009-01-01

    Objectives To explore the change of endogenic nerve growth factor (NGF) expression in human glioma cells infected with human cytomegalovirus (HCMV). Methods U251 cells were cultured in RPMI 1640 culture medium and infected with HCMV AD169 strain in vitro to establish a cell model of viral infection. Morphologic changes of U251 cells were observed under inverted microscope before and after infection with HCMV. Expression of NGF gene and protein of cells was detected by RT-PCR and Western blotting before and after infection with HCMV. Results The cytopathic effects of HCMV-infected cells appeared on day 5 after infection. However, differential NGF expression was evident on day 7. NGF expression was decreased significantly in U251 cells on day 7 after infection in comparison with control group (P<0.05). Conclusion HCMV can down-regulate endogenous NGF levels in human glioma cell line U251.

  8. A Metabolic Biofuel Cell: Conversion of Human Leukocyte Metabolic Activity to Electrical Currents

    Directory of Open Access Journals (Sweden)

    Cui X Tracy

    2011-05-01

    Full Text Available Abstract An investigation of the electrochemical activity of human white blood cells (WBC for biofuel cell (BFC applications is described. WBCs isolated from whole human blood were suspended in PBS and introduced into the anode compartment of a proton exchange membrane (PEM fuel cell. The cathode compartment contained a 50 mM potassium ferricyanide solution. Average current densities between 0.9 and 1.6 μA cm-2 and open circuit potentials (Voc between 83 and 102 mV were obtained, which were both higher than control values. Cyclic voltammetry was used to investigate the electrochemical activity of the activated WBCs in an attempt to elucidate the mechanism of electron transfer between the cells and electrode. Voltammograms were obtained for the WBCs, including peripheral blood mononuclear cells (PBMCs - a lymphocyte-monocyte mixture isolated on a Ficoll gradient, a B lymphoblastoid cell line (BLCL, and two leukemia cell lines, namely K562 and Jurkat. An oxidation peak at about 363 mV vs. SCE for the PMA (phorbol ester activated primary cells, with a notable absence of a reduction peak was observed. Oxidation peaks were not observed for the BLCL, K562 or Jurkat cell lines. HPLC confirmed the release of serotonin (5-HT from the PMA activated primary cells. It is believed that serotonin, among other biochemical species released by the activated cells, contributes to the observed BFC currents.

  9. CD133(+) human umbilical cord blood stem cells enhance angiogenesis in experimental chronic hepatic fibrosis.

    Science.gov (United States)

    Elkhafif, Nagwa; El Baz, Hanan; Hammam, Olfat; Hassan, Salwa; Salah, Faten; Mansour, Wafaa; Mansy, Soheir; Yehia, Hoda; Zaki, Ahmed; Magdy, Ranya

    2011-01-01

    The in vivo angiogenic potential of transplanted human umbilical cord blood (UCB) CD133(+) stem cells in experimental chronic hepatic fibrosis induced by murine schistosomiasis was studied. Enriched cord blood-derived CD133(+) cells were cultured in primary medium for 3 weeks. Twenty-two weeks post-Schistosomiasis infection in mice, after reaching the chronic hepatic fibrotic stage, transplantation of stem cells was performed and mice were sacrificed 3 weeks later. Histopathology and electron microscopy showed an increase in newly formed blood vessels and a decrease in the fibrosis known for this stage of the disease. By immunohistochemical analysis the newly formed blood vessels showed positive expression of the human-specific angiogenic markers CD31, CD34 and von Willebrand factor. Few hepatocyte-like polygonal cells showed positive expression of human vascular endothelial growth factor and inducible nitric oxide synthase. The transplanted CD133(+) human stem cells primarily enhanced hepatic angiogenesis and neovascularization and contributed to repair in a paracrine manner by creating a permissive environment that enabled proliferation and survival of damaged cells rather than by direct differentiation to hepatocytes. A dual advantage of CD133(+) cell therapy in hepatic disease is suggested based on its capability of hematopoietic and endothelial differentiation.

  10. Derivation of novel human ground state naive pluripotent stem cells.

    Science.gov (United States)

    Gafni, Ohad; Weinberger, Leehee; Mansour, Abed AlFatah; Manor, Yair S; Chomsky, Elad; Ben-Yosef, Dalit; Kalma, Yael; Viukov, Sergey; Maza, Itay; Zviran, Asaf; Rais, Yoach; Shipony, Zohar; Mukamel, Zohar; Krupalnik, Vladislav; Zerbib, Mirie; Geula, Shay; Caspi, Inbal; Schneir, Dan; Shwartz, Tamar; Gilad, Shlomit; Amann-Zalcenstein, Daniela; Benjamin, Sima; Amit, Ido; Tanay, Amos; Massarwa, Rada; Novershtern, Noa; Hanna, Jacob H

    2013-12-12

    Mouse embryonic stem (ES) cells are isolated from the inner cell mass of blastocysts, and can be preserved in vitro in a naive inner-cell-mass-like configuration by providing exogenous stimulation with leukaemia inhibitory factor (LIF) and small molecule inhibition of ERK1/ERK2 and GSK3β signalling (termed 2i/LIF conditions). Hallmarks of naive pluripotency include driving Oct4 (also known as Pou5f1) transcription by its distal enhancer, retaining a pre-inactivation X chromosome state, and global reduction in DNA methylation and in H3K27me3 repressive chromatin mark deposition on developmental regulatory gene promoters. Upon withdrawal of 2i/LIF, naive mouse ES cells can drift towards a primed pluripotent state resembling that of the post-implantation epiblast. Although human ES cells share several molecular features with naive mouse ES cells, they also share a variety of epigenetic properties with primed murine epiblast stem cells (EpiSCs). These include predominant use of the proximal enhancer element to maintain OCT4 expression, pronounced tendency for X chromosome inactivation in most female human ES cells, increase in DNA methylation and prominent deposition of H3K27me3 and bivalent domain acquisition on lineage regulatory genes. The feasibility of establishing human ground state naive pluripotency in vitro with equivalent molecular and functional features to those characterized in mouse ES cells remains to be defined. Here we establish defined conditions that facilitate the derivation of genetically unmodified human naive pluripotent stem cells from already established primed human ES cells, from somatic cells through induced pluripotent stem (iPS) cell reprogramming or directly from blastocysts. The novel naive pluripotent cells validated herein retain molecular characteristics and functional properties that are highly similar to mouse naive ES cells, and distinct from conventional primed human pluripotent cells. This includes competence in the generation

  11. Mesenchymal Stem Cell Levels of Human Spinal Tissues.

    Science.gov (United States)

    Harris, Liam; Vangsness, C Thomas

    2017-09-06

    .: Systematic Review. .: The aim of this study was to investigate, quantify, compare and compile the various mesenchymal stem cell tissue sources within human spinal tissues to act as a compendium for clinical and research application. .: Recent years have seen a dramatic increase in academic and clinical understanding of human mesenchymal stem cells (MSCs). Previously limited to cells isolated from bone marrow, the past decade has illicited the characterization and isolation of human MSCs from adipose, bone marrow, synovium, muscle, periosteum, peripheral blood, umbilical cord, placenta and numerous other tissues. As researchers explore practical applications of cells in these tissues, the absolute levels of MSCs in specific spinal tissue will be critical to guide future research. .: The PubMED, MEDLINE, EMBASE and Cochrane databases were searched for articles relating to the harvest, characterization, isolation and quantification of human mesenchymal stem cells from spinal tissues. Selected articles were examined for relevant data, categorized according to type of spinal tissue, and when possible, standardized to facilitate comparisons between sites. .: Human mesenchymal stem cell levels varied widely between spinal tissues. Yields for Intervertebral disc demonstrated roughly 5% of viable cells to be positive for MSC surface markers. Cartilage endplate cells yielded 18,500- 61,875 cells/ 0.8 mm thick sample of cartilage end plate. Ligamentum flavum yielded 250,000- 500,000 cells per gram of tissue. Annulus fibrosus FACS treatment found 29% of cells positive for MSC marker Stro-1. Nucleus pulposus yielded mean tissue samples of 40,584-234,137 MSCs/gram of tissue. .: Numerous tissues within and surrounding the spine represent a consistent and reliable source for the harvest and isolation of human mesenchymal stem cells. Among the tissues of the spine, the annulus fibrosus and ligamentum flavum each offer considerable levels of mesenchymal stem cells, and may

  12. Radiogenic transformation of human mammary epithelial cells in vitro

    Science.gov (United States)

    Yang, T. C.; Georgy, K. A.; Tavakoli, A.; Craise, L. M.; Durante, M.

    1996-01-01

    Cancer induction by space radiations is a major concern for manned space exploration. Accurate assessment of radiation risk at low doses requires basic understanding of mechanism(s) of radiation carcinogenesis. For determining the oncogenic effects of ionizing radiation in human epithelial cells, we transformed a mammary epithelial cell line (185B5), which was immortalized by benzo(a)pyrene, with energetic heavy ions and obtained several transformed clones. These transformed cells showed growth properties on Matrigel similar to human mammary tumor cells. To better understand the mechanisms of radiogenic transformation of human cells, we systematically examined the alterations in chromosomes and cancer genes. Among 16 autosomes examined for translocations, by using fluorescence in situ hybridization (FISH) technique, chromosomes 3, 12, 13, 15, 16, and 18 appeared to be normal in transformed cells. Chromosomes 1, 4, 6, 8, and 17 in transformed cells, however, showed patterns different from those in nontransformed cells. Southern blot analyses indicated no detectable alterations in myc, ras, Rb, or p53 genes. Further studies of chromosome 17 by using in situ hybridization with unique sequence p53 gene probe and a centromere probe showed no loss of p53 gene in transformed cells. Experimental results from cell fusion studies indicated that the transforming gene(s) is recessive. The role of genomic instability and tumor suppressor gene(s) in radiogenic transformation of human breast cells remains to be identified.

  13. Diversity of extracellular vesicles in human ejaculates revealed by cryo-electron microscopy

    Directory of Open Access Journals (Sweden)

    Johanna L. Höög

    2015-11-01

    Full Text Available Human ejaculates contain extracellular vesicles (EVs, that to a large extent are considered to originate from the prostate gland, and are often denominated “prostasomes.” These EVs are important for human fertility, for example by promoting sperm motility and by inducing immune tolerance of the female immune system to the spermatozoa. So far, the EVs present in human ejaculate have not been studied in their native state, inside the seminal fluid without prior purification and isolation procedures. Using cryo-electron microscopy and tomography, we performed a comprehensive inventory of human ejaculate EVs. The sample was neither centrifuged, fixed, filtered or sectioned, nor were heavy metals added. Approximately 1,500 extracellular structures were imaged and categorized. The extracellular environment of human ejaculate was found to be diverse, with 5 major subcategories of EVs and 6 subcategories of extracellular membrane compartments, including lamellar bodies. Furthermore, 3 morphological features, including electron density, double membrane bilayers and coated surface, are described in all subcategories. This study reveals that the extracellular environment in human ejaculate is multifaceted. Several novel morphological EV subcategories are identified and clues to their cellular origin may be found in their morphology. This inventory is therefore important for developing future experimental approaches, and to interpret previously published data to understand the role of EVs for human male fertility.

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

    Directory of Open Access Journals (Sweden)

    Stefania Bruno

    2016-01-01

    Full Text Available Human liver stem cells (HLSCs are