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Sample records for hi559 hepatocytes display

  1. Hepatocyte Growth Factor Reduces Free Cholesterol-Mediated Lipotoxicity in Primary Hepatocytes by Countering Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Mayra Domínguez-Pérez

    2016-01-01

    Full Text Available Cholesterol overload in the liver has shown toxic effects by inducing the aggravation of nonalcoholic fatty liver disease to steatohepatitis and sensitizing to damage. Although the mechanism of damage is complex, it has been demonstrated that oxidative stress plays a prominent role in the process. In addition, we have proved that hepatocyte growth factor induces an antioxidant response in hepatic cells; in the present work we aimed to figure out the protective effect of this growth factor in hepatocytes overloaded with free cholesterol. Hepatocytes from mice fed with a high-cholesterol diet were treated or not with HGF, reactive oxygen species present in cholesterol overloaded hepatocytes significantly decreased, and this effect was particularly associated with the increase in glutathione and related enzymes, such as γ-gamma glutamyl cysteine synthetase, GSH peroxidase, and GSH-S-transferase. Our data clearly indicate that HGF displays an antioxidant response by inducing the glutathione-related protection system.

  2. Pegylated interferons Lambda-1a and alfa-2a display different gene induction and cytokine and chemokine release profiles in whole blood, human hepatocytes and peripheral blood mononuclear cells.

    Science.gov (United States)

    Freeman, J; Baglino, S; Friborg, J; Kraft, Z; Gray, T; Hill, M; McPhee, F; Hillson, J; Lopez-Talavera, J C; Wind-Rotolo, M

    2014-06-01

    Pegylated interferon-lambda-1a (Lambda), a type III interferon (IFN) in clinical development for the treatment of chronic HCV infection, has shown comparable efficacy and an improved safety profile to a regimen based on pegylated IFN alfa-2a (alfa). To establish a mechanistic context for this improved profile, we investigated the ex vivo effects of Lambda and alfa on cytokine and chemokine release, and on expression of IFN-stimulated genes (ISGs) in primary human hepatocytes and peripheral blood mononuclear cells (PBMCs) from healthy subjects. Our findings were further compared with changes observed in blood analysed from HCV-infected patients treated with Lambda or alfa in clinical studies. mRNA transcript and protein expression of the IFN-λ-limiting receptor subunit was lower compared with IFN-α receptor subunits in all cell types. Upon stimulation, alfa and Lambda induced ISG expression in hepatocytes and PBMCs, although in PBMCs Lambda-induced ISG expression was modest. Furthermore, alfa and Lambda induced release of cytokines and chemokines from hepatocytes and PBMCs, although differences in their kinetics of induction were observed. In HCV-infected patients, alfa treatment induced ISG expression in whole blood after single and repeat dosing. Lambda treatment induced modest ISG expression after single dosing and showed no induction after repeat dosing. Alfa and Lambda treatment increased IP-10, iTAC, IL-6, MCP-1 and MIP-1β levels in serum, with alfa inducing higher levels of all mediators compared with Lambda. Overall, ex vivo and in vivo induction profiles reported in this analysis strongly correlate with clinical observations of fewer related adverse events for Lambda vs those typically associated with alfa. © 2014 John Wiley & Sons Ltd.

  3. Targeted deletion of hepatocyte Ikkβ confers growth advantages

    International Nuclear Information System (INIS)

    Koch, Katherine S.; Maeda, Shin; He, Guobin; Karin, Michael; Leffert, Hyam L.

    2009-01-01

    Mice lacking hepatocyte IKKβ (Ikkβ Δhep ) are defective in TNFα-activation of hepatocellular transcription factor NF-κB, and highly susceptible to hepatotoxicity. Following diethylnitrosamine (DEN) exposure, Ikkβ Δhep mice develop more hepatocellular carcinoma (HCC) than control mice due partly to enhanced DEN-induced hepatocyte death. Here we show that Ikkβ Δhep hepatocytes display growth advantages over normal hepatocytes consisting of precocious PCNA and cyclin D1 expression during liver regeneration (shortened hepatocyte G 0 → G 1 transitions), and enhanced recovery efficiency, cyclin D1 expression and cell proliferation after plating. Ex vivo deletion of Ikkβ also accelerates hepatocyte growth. Ikkβ Δhep hepatocyte proliferative responses show heightened sensitivity to TGFα and TNFα, and heightened expression of fibronectin, collagens I/III, nidogen, β-actin and integrin β1 mRNAs. These findings suggest that altered mitogen signaling and expression of extracellular matrix and its associated components underlie growth advantages. Increased HCC development in Ikkβ Δhep mice may also be caused by growth advantages of surviving Ikkβ-deleted hepatocytes.

  4. Repolarization of hepatocytes in culture.

    Science.gov (United States)

    Talamini, M A; Kappus, B; Hubbard, A

    1997-01-01

    We have evaluated the biochemical, morphological, and functional redevelopment of polarity in freshly isolated hepatocytes cultured using a double layer collagen gel sandwich technique. Western blot analysis showed increased cellular levels of the cell adhesion protein uvomorulin as cultured hepatocytes repolarized. Immunofluorescence studies using antibodies against domain-specific membrane proteins showed polarity as early as 48 hours, although the pattern of the polymeric Immunoglobulin-A receptor (pIgA-R) differed from in vivo liver. Electron microscopy showed developing bile canaliculi at 1 day. However, the functional presence of tight junctions was absent at 1 day, but present at 5 days. We further showed functional polarity to be present at 4 days by documenting the ability of cultured hepatocytes to metabolize and excrete fluorescein diacetate into visible bile canaliculi. We conclude that hepatocytes cultured appropriately develop morphological and functional polarity. Hepatocyte culture is therefore a useful tool for the study of mechanisms responsible for the development of polarized function.

  5. High efficient differentiation of functional hepatocytes from porcine induced pluripotent stem cells.

    Directory of Open Access Journals (Sweden)

    Ying Ao

    Full Text Available Hepatocyte transplantation is considered to be a promising therapy for patients with liver diseases. Induced pluripotent stem cells (iPSCs provide an unlimited source for the generation of functional hepatocytes. In this study, we generated iPSCs from porcine ear fibroblasts (PEFs by overexpressing Sox2, Klf4, Oct4, and c-Myc (SKOM, and developed a novel strategy for the efficient differentiation of hepatocyte-like cells from porcine iPSCs by following the processes of early liver development. The differentiated cells displayed the phenotypes of hepatocytes, exhibited classic hepatocyte-associated bio-functions, such as LDL uptake, glycogen storage and urea secretion, as well as possessed the metabolic activities of cytochrome P-450 (CYP 3A and 2C. Furthermore, we compared the hepatocyte differentiation efficacy of our protocol with another published method, and the results demonstrated that our differentiation strategy could significantly improve the generation of morphological and functional hepatocyte-like cells from porcine iPSCs. In conclusion, this study establishes an efficient method for in vitro generation of functional hepatocytes from porcine iPSCs, which could represent a promising cell source for preclinical testing of cell-based therapeutics for liver failure and for pharmacological applications.

  6. A fat option for the pig: Hepatocytic differentiated mesenchymal stem cells for translational research

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    Brückner, Sandra, E-mail: sandra.brueckner@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); Tautenhahn, Hans-Michael, E-mail: hans-michael.tautenhahn@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); TRM, Translational Centre for Regenerative Medicine, Philipp-Rosenthal-Str. 55, Leipzig D-04103 (Germany); Winkler, Sandra, E-mail: sandra.pelz@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); Stock, Peggy, E-mail: peggy.stock@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); Dollinger, Matthias, E-mail: matthias.dollinger@uniklinik-ulm.de [University Hospital Ulm, First Department of Medicine, Albert-Einstein-Allee 23, Ulm D-89081 (Germany); Christ, Bruno, E-mail: bruno.christ@medizin.uni-leipzig.de [University Hospital Leipzig, Department of Visceral, Transplantation, Thoracic and Vascular Surgery, Liebigstraße 21, Leipzig D-04103 (Germany); TRM, Translational Centre for Regenerative Medicine, Philipp-Rosenthal-Str. 55, Leipzig D-04103 (Germany)

    2014-02-15

    Study background: Extended liver resection is the only curative treatment option of liver cancer. Yet, the residual liver may not accomplish the high metabolic and regenerative capacity needed, which frequently leads to acute liver failure. Because of their anti-inflammatory and -apoptotic as well as pro-proliferative features, mesenchymal stem cells differentiated into hepatocyte-like cells might provide functional and regenerative compensation. Clinical translation of basic research requires pre-clinical approval in large animals. Therefore, we characterized porcine mesenchymal stem cells (MSC) from adipose tissue and bone marrow and their hepatocyte differentiation potential for future assessment of functional liver support after surgical intervention in the pig model. Methods: Mesenchymal surface antigens and multi-lineage differentiation potential of porcine MSC isolated by collagenase digestion either from bone marrow or adipose tissue (subcutaneous/visceral) were assessed by flow cytometry. Morphology and functional properties (urea-, glycogen synthesis and cytochrome P450 activity) were determined during culture under differentiation conditions and compared with primary porcine hepatocytes. Results: MSC from porcine adipose tissue and from bone marrow express the typical mesenchymal markers CD44, CD29, CD90 and CD105 but not haematopoietic markers. MSC from both sources displayed differentiation into the osteogenic as well as adipogenic lineage. After hepatocyte differentiation, expression of CD105 decreased significantly and cells adopted the typical polygonal morphology of hepatocytes. Glycogen storage was comparable in adipose tissue- and bone marrow-derived cells. Urea synthesis was about 35% lower in visceral than in subcutaneous adipose tissue-derived MSC. Cytochrome P450 activity increased significantly during differentiation and was twice as high in hepatocyte-like cells generated from bone marrow as from adipose tissue. Conclusion: The hepatocyte

  7. A fat option for the pig: Hepatocytic differentiated mesenchymal stem cells for translational research

    International Nuclear Information System (INIS)

    Brückner, Sandra; Tautenhahn, Hans-Michael; Winkler, Sandra; Stock, Peggy; Dollinger, Matthias; Christ, Bruno

    2014-01-01

    Study background: Extended liver resection is the only curative treatment option of liver cancer. Yet, the residual liver may not accomplish the high metabolic and regenerative capacity needed, which frequently leads to acute liver failure. Because of their anti-inflammatory and -apoptotic as well as pro-proliferative features, mesenchymal stem cells differentiated into hepatocyte-like cells might provide functional and regenerative compensation. Clinical translation of basic research requires pre-clinical approval in large animals. Therefore, we characterized porcine mesenchymal stem cells (MSC) from adipose tissue and bone marrow and their hepatocyte differentiation potential for future assessment of functional liver support after surgical intervention in the pig model. Methods: Mesenchymal surface antigens and multi-lineage differentiation potential of porcine MSC isolated by collagenase digestion either from bone marrow or adipose tissue (subcutaneous/visceral) were assessed by flow cytometry. Morphology and functional properties (urea-, glycogen synthesis and cytochrome P450 activity) were determined during culture under differentiation conditions and compared with primary porcine hepatocytes. Results: MSC from porcine adipose tissue and from bone marrow express the typical mesenchymal markers CD44, CD29, CD90 and CD105 but not haematopoietic markers. MSC from both sources displayed differentiation into the osteogenic as well as adipogenic lineage. After hepatocyte differentiation, expression of CD105 decreased significantly and cells adopted the typical polygonal morphology of hepatocytes. Glycogen storage was comparable in adipose tissue- and bone marrow-derived cells. Urea synthesis was about 35% lower in visceral than in subcutaneous adipose tissue-derived MSC. Cytochrome P450 activity increased significantly during differentiation and was twice as high in hepatocyte-like cells generated from bone marrow as from adipose tissue. Conclusion: The hepatocyte

  8. [The polyploidization characteristics of the hepatocytes of the mouse-like hamster Calomyscus mystax].

    Science.gov (United States)

    Anatskaia, O V; Malikov, V G; Meĭer, M N; Kudriavtsev, B N

    1995-01-01

    A cytophotometric measurement of DNA content in hepatocytes of maturing mouse-like hamsters was made. Cells belonging to ordinary mammalian ploidy classes 2c, 2c x 2, 4c, and 4c x 2 made about 90% of the hepatocyte population. The share of binucleated cells wa high (about 80%), the majority of these cells being 2c X 2 hepatocytes. Binucleated cells with tetraploid and diploid nuclei occur in almost every animal. An average hepatocyte ploidy level in mouse-like hamster is 4.6c. The main peculiarity of parenchymal liver cell populations is that up 5% of hepatocytes contain 3--11 nuclei of different ploidy classes. Multinucleated cells increase in number from 1.5% to 4% within the period from one year (the age of maturation) to two years. Later on their percentage does not change. It is found that in binucleated and multinucleated hepatocytes DNA synthesis can proceed asynchronously. Asynchrony in DNA synthesis elevates as the number of nuclei increases. Among the 2c x 2 and 2c x 3 cells an uneven distribution of 3H-thymidine label can occur, respectively, in 5 and in 50% cases, whereas all the cells with more than 3 nuclei display an uneven an uneven 3H-thymidin label distribution. The formation of multinucleated cells is supposed to be associated with asynchrony in DNA-synthesis in binucleated cells and with the restitution of mitosis.

  9. Cholangiocarcinoma in Cirrhosis: Value of Hepatocyte Specific Magnetic Resonance Imaging.

    Science.gov (United States)

    Piscaglia, Fabio; Iavarone, Massimo; Galassi, Marzia; Vavassori, Sara; Renzulli, Matteo; Forzenigo, Laura Virginia; Granito, Alessandro; Salvatore, Veronica; Sangiovanni, Angelo; Golfieri, Rita; Colombo, Massimo; Bolondi, Luigi

    2015-10-01

    The diagnosis of intrahepatic cholangiocellular carcinoma (ICC) remains elusive at imaging, which is a critical issue in cirrhotic patients in whom a diagnosis of hepatocellular carcinoma (HCC) can be established only by imaging. The aim of the study was to evaluate the potential of MRI in the diagnosis of ICC in cirrhosis using 'hepatocyte-specific' Gadolinium (Gd)-based contrast agents. Sixteen histologically proven and retrospectively identified ICCs on cirrhosis were investigated with hepatocyte-specific magnetic resonance contrast agents (6 in Bologna with Gd-EOB-DTPA and 10 in Milan with Gd-BOPTA). The control group consisted of 41 consecutively and prospectively collected nodules (31 HCCs) imaged with Gd-EOB-DTPA. Fifteen ICC nodules (94%) displayed hypointensity in the hepatobiliary phase, suggesting malignancy. Thirteen cholangiocarcinomas (81%) showed hyperenhancement in the venous phase. Only 2 cholangiocarcinoma nodules showed hypoenhancement in the venous phase, corresponding to washout, in both cases preceded by rim enhancement in arterial phase. All the hepatocarcinomas showed hypointensity in hepatobiliary phase, but was always preceded by hypointensity in the venous phase; arterial rim enhancement was never observed in any hepatocarcinoma or regenerative nodule. MRI with hepatocyte-specific Gd-based contrast agents showed a pattern of malignancy in almost all the ICCs, concurrently avoiding misdiagnosis with hepatocarcinoma. These findings suggest a greater diagnostic capacity for this technique compared with the results of MRI with conventional contrast agents reported in the literature in this setting. © 2015 S. Karger AG, Basel.

  10. Factor VIIa binding and internalization in hepatocytes

    DEFF Research Database (Denmark)

    Hjortoe, G; Sorensen, B B; Petersen, L C

    2005-01-01

    The liver is believed to be the primary clearance organ for coagulation proteases, including factor VIIa (FVIIa). However, at present, clearance mechanisms for FVIIa in liver are unknown. To obtain information on the FVIIa clearance mechanism, we investigated the binding and internalization...... no effect. HEPG2 cells internalized FVIIa with a rate of 10 fmol 10(-5) cells h(-1). In contrast to HEPG2 cells, FVIIa binding to primary rat hepatocytes was completely independent of TF, and excess unlabeled FVIIa partly reduced the binding of 125I-FVIIa to rat hepatocytes. Further, compared with HEPG2...... cells, three- to fourfold more FVIIa bound to rat primary hepatocytes, and the bound FVIIa was internalized at a faster rate. Similar FVIIa binding and internalization profiles were observed in primary human hepatocytes. Plasma inhibitors had no effect on FVIIa binding and internalization in hepatocytes...

  11. Pretreatment with mixed-function oxidase inducers increases the sensitivity of the hepatocyte/DNA repair assay

    International Nuclear Information System (INIS)

    Shaddock, J.G.; Heflich, R.H.; McMillan, D.C.; Hinson, J.A.; Casciano, D.A.

    1989-01-01

    A recent National Toxicology Program evaluation indicates that the rat hepatocyte/DNA repair assay has a high false-negative rate and that it is insensitive to some genotoxic hepatocarcinogens as well as other species and organ-specific carcinogens. In this study, the authors examined whether the sensitivity of the hepatocyte/DNA repair assay might be increased through animal pretreatment with various hepatic mixed-function oxidase inducers, i.e., Aroclor 1254, phenobarbital, and 3,3',4,4'-tetrachloroazobenzene (TCAB). The effects on unscheduled DNA synthesis (UDS), a measured of DNA damage and repair, were studied in cultures exposed to known and/or potential carcinogens that had been evaluated as negative or questionable or that produced conflicting results with hepatocytes isolated from uninduced animals. 4,4'-Oxydianiline, 1-nitropy-rene, and TCAB produced concentration-dependent increases in UDS in hepatocytes from rats pretreated with Aroclor 1254. 4,4'-Oxydianiline and TCAB also induced a dose-dependent increase in DNA repair in hepatocytes from rats pretreated with phenobarbital, whereas 1-nitropyrene was negative. These data indicate that the limited sensitivity to chemical carcinogens displayed by the hepatocyte/DNA repair assay may be increased by using hepatocytes isolated from animals exposed to hepatic mixed-function oxidase inducers

  12. Pretreatment with mixed-function oxidase inducers increases the sensitivity of the hepatocyte/DNA repair assay

    Energy Technology Data Exchange (ETDEWEB)

    Shaddock, J.G.; Heflich, R.H.; McMillan, D.C.; Hinson, J.A.; Casciano, D.A. (National Center for Toxicological Research, Jefferson, AK (USA) Univ. of Arkansas for Medical Sciences, Little Rock (USA))

    1989-01-01

    A recent National Toxicology Program evaluation indicates that the rat hepatocyte/DNA repair assay has a high false-negative rate and that it is insensitive to some genotoxic hepatocarcinogens as well as other species and organ-specific carcinogens. In this study, the authors examined whether the sensitivity of the hepatocyte/DNA repair assay might be increased through animal pretreatment with various hepatic mixed-function oxidase inducers, i.e., Aroclor 1254, phenobarbital, and 3,3{prime},4,4{prime}-tetrachloroazobenzene (TCAB). The effects on unscheduled DNA synthesis (UDS), a measured of DNA damage and repair, were studied in cultures exposed to known and/or potential carcinogens that had been evaluated as negative or questionable or that produced conflicting results with hepatocytes isolated from uninduced animals. 4,4{prime}-Oxydianiline, 1-nitropy-rene, and TCAB produced concentration-dependent increases in UDS in hepatocytes from rats pretreated with Aroclor 1254. 4,4{prime}-Oxydianiline and TCAB also induced a dose-dependent increase in DNA repair in hepatocytes from rats pretreated with phenobarbital, whereas 1-nitropyrene was negative. These data indicate that the limited sensitivity to chemical carcinogens displayed by the hepatocyte/DNA repair assay may be increased by using hepatocytes isolated from animals exposed to hepatic mixed-function oxidase inducers.

  13. Hepatocyte polarization is essential for the productive entry of the hepatitis B virus.

    Science.gov (United States)

    Schulze, Andreas; Mills, Kerry; Weiss, Thomas S; Urban, Stephan

    2012-02-01

    Human hepatitis B virus (HBV) is characterized by a high species specificity and a distinct liver tropism. Within the liver, HBV replication occurs in differentiated and polarized hepatocytes. Accordingly, the in vitro HBV infection of primary human hepatocytes (PHHs) and the human hepatoma cell line, HepaRG, is restricted to differentiated, hepatocyte-like cells. Though preparations of PHH contain up to 100% hepatic cells, cultures of differentiated HepaRG cells are a mixture of hepatocyte-like and biliary-like epithelial cells. We used PHH and HepaRG cells and compared the influence of virus inoculation dose, cell differentiation, and polarization on productive HBV infection. At multiplicities of genome equivalents (mge) >8,000, almost 100% of PHHs could be infected. In contrast, only a subset of HepaRG cells stained positive for HBcAg at comparable or even higher mge. Infection predominantly occurred at the edges of islands of hepatocyte-like HepaRG cells. This indicates a limited accessibility of the HBV receptor, possibly as a result of its polar sorting. Multidrug resistance protein 2 (MRP2), a marker selectively transported to the apical (i.e., canalicular) cell membrane, revealed two polarization phenotypes of HepaRG cells. HBV infection within the islands of hepatocyte-like HepaRG cells preferentially occurred in cells that resemble PHH, exhibiting canalicular structures. However, disruption of cell-cell junctions allowed the additional infection of cells that do not display a PHH-like polarization. HBV enters hepatocytes via the basolateral membrane. This model, at least partially, explains the difference of PHH and HepaRG cells in infection efficacy, provides insights into natural HBV infection, and establishes a basis for optimization of the HepaRG infection system. Copyright © 2011 American Association for the Study of Liver Diseases.

  14. β-Adrenergic induction of lipolysis in hepatocytes is inhibited by ethanol exposure.

    Science.gov (United States)

    Schott, Micah B; Rasineni, Karuna; Weller, Shaun G; Schulze, Ryan J; Sletten, Arthur C; Casey, Carol A; McNiven, Mark A

    2017-07-14

    In liver steatosis ( i.e. fatty liver), hepatocytes accumulate many large neutral lipid storage organelles known as lipid droplets (LDs). LDs are important in the maintenance of energy homeostasis, but the signaling mechanisms that stimulate LD metabolism in hepatocytes are poorly defined. In adipocytes, catecholamines target the β-adrenergic (β-AR)/cAMP pathway to activate cytosolic lipases and induce their recruitment to the LD surface. Therefore, the goal of this study was to determine whether hepatocytes, like adipocytes, also undergo cAMP-mediated lipolysis in response to β-AR stimulation. Using primary rat hepatocytes and human hepatoma cells, we found that treatment with the β-AR agent isoproterenol caused substantial LD loss via activation of cytosolic lipases adipose triglyceride lipase (ATGL) and hormone-sensitive lipase (HSL). β-Adrenergic stimulation rapidly activated PKA, which led to the phosphorylation of ATGL and HSL and their recruitment to the LD surface. To test whether this β-AR-dependent lipolysis pathway was altered in a model of alcoholic fatty liver, primary hepatocytes from rats fed a 6-week EtOH-containing Lieber-DeCarli diet were treated with cAMP agonists. Compared with controls, EtOH-exposed hepatocytes showed a drastic inhibition in β-AR/cAMP-induced LD breakdown and the phosphorylation of PKA substrates, including HSL. This observation was supported in VA-13 cells, an EtOH-metabolizing human hepatoma cell line, which displayed marked defects in both PKA activation and isoproterenol-induced ATGL translocation to the LD periphery. In summary, these findings suggest that β-AR stimulation mobilizes cytosolic lipases for LD breakdown in hepatocytes, and perturbation of this pathway could be a major consequence of chronic EtOH insult leading to fatty liver.

  15. Generation of human hepatocytes by stem cell technology: definition of the hepatocyte.

    Science.gov (United States)

    Hengstler, Jan G; Brulport, Marc; Schormann, Wiebke; Bauer, Alexander; Hermes, Matthias; Nussler, Andreas K; Fandrich, Fred; Ruhnke, Maren; Ungefroren, Hendrik; Griffin, Louise; Bockamp, Ernesto; Oesch, Franz; von Mach, Marc-Alexander

    2005-06-01

    Since 1999, numerous articles have reported the generation of hepatocytes from different types of extrahepatic stem or precursor cells. This opens exciting new possibilities for pharmacology and toxicology, as well as for cell therapy. Hepatocyte marker expression, including albumin, cytokeratin 18, c-met, alpha-fetoprotein and cytochrome P450 3A4 and -2B6, has been observed after transplantation of different types of human stem cells into the liver of laboratory animals or in vitro after incubation with cytokines. These intriguing observations have prompted scientists to classify stem cell-derived cell populations as hepatocytes. However, this conclusion may be premature. It has been shown that factors of the liver microenvironment can induce expression of a limited number of hepatocyte marker genes in nonhepatic cell types. To conclude on the grounds of a limited number of markers that these cells are true hepatocytes is not indicated. In this case one should carefully evaluate crucial hepatocyte-defining enzymatic properties. The present article: i) reviews studies describing the fate of extrahepatic human stem and precursor cells in livers of laboratory animals, including the possibility of cell fusion; and ii) critically discusses the phenotype of stem cells after application of various differentiation protocols aimed at generating human hepatocytes. In addition, the necessary criteria needed for defining a true hepatocyte are suggested. Establishing the necessary properties for stem cell-derived hepatocytes is timely and reasonable, and thus avoids further misleading semantic confusion. Finally, it is essential to understand that the definition of a bona fide hepatocyte should not be limited to qualitative assays, such as reverse transcriptase polymerase chain reaction and immunohistochemistry, but has to include a quantitative analysis of enzymatic activities, which allows direct comparison with primary hepatocytes. Although the stem cell-derived-hepatocyte

  16. Comparison of the biological features between human fetal hepatocyte and immortalized L-02 hepatocyte in vitro

    International Nuclear Information System (INIS)

    Kong Weiwei; Teng Gaojun

    2004-01-01

    Objective: To evaluate the feasibilities of the potential donors in liver cell transplantation using the human fetal hepatocytes and immortalized L-02 hepatocytes by comparing their biological features. Methods: Human fetal hepatocytes were isolated from aborted fetal livers (gestational ages from 14 w to 24 w) by an improved two-stage perfusion method and cultured in a conditioned medium without any growth factors. α-fetal protein (AFP) and albumin (ALB) were detected by radioimmunoassay (RIA) and cytokeratin-19 (CK-19 ) was identified by cellular immunochemistry study. Immortalized L-02 hepatocytes were cultured in the same condition and the characteristic proteins were detected by the same methods. Results: The viability of human fetal hepatocytes was approximately 95% using the perfusion method, and the maximum survival time of the cultured hepatocytes was 3 weeks. The expression of AFP, ALB, and CK19 was detected at the same time, especially during Day 3 to Day 7 in the culture. By comparison, the proliferation ability of L-02 hepatocyte was greater, although with a lower level of ALB secretion. The expression of AFP and CK19 was not detected. Furthermore, during the long culture, L-02 hepatocytes may undergo a morphologic change and fail to express ALB. Conclusion: Human fetal hepatocyte may be a practical donor for hepatocyte transplantation with its high-level protein expression and potential bi-differentiation ability. In view of the absent expression of ALB and the morphologic change in culture, although with better proliferation, L-02 hepatocyte seems not useful for hepatocyte transplantation

  17. Functional displays

    International Nuclear Information System (INIS)

    Angelis De, F.; Haentjens, J.

    1995-01-01

    The Functional Displays are directly derived from the Man-Machine Design key document: Function-Based Task Analysis. The presentation defines and describes the goals-means structure of the plant function along with applicable control volumes and parameters of interest. The purpose of the subject is to show, through an example of a preliminary design, what the main parts of a function are. (3 figs.)

  18. Display hardware

    International Nuclear Information System (INIS)

    Myers, D.R.

    1983-01-01

    To appreciate the limitations and possibilities of computer graphics it is necessary to have some acquaintance with the available technology. The aim of this chapter is to mention briefly the different display types and their 'ball-park' price ranges. It must be stressed that prices change rapidly, and so those quoted here are only intended to give an idea of the cost at the time of writing.

  19. Hepatocyte specific expression of human cloned genes

    Energy Technology Data Exchange (ETDEWEB)

    Cortese, R

    1986-01-01

    A large number of proteins are specifically synthesized in the hepatocyte. Only the adult liver expresses the complete repertoire of functions which are required at various stages during development. There is therefore a complex series of regulatory mechanisms responsible for the maintenance of the differentiated state and for the developmental and physiological variations in the pattern of gene expression. Human hepatoma cell lines HepG2 and Hep3B display a pattern of gene expression similar to adult and fetal liver, respectively; in contrast, cultured fibroblasts or HeLa cells do not express most of the liver specific genes. They have used these cell lines for transfection experiments with cloned human liver specific genes. DNA segments coding for alpha1-antitrypsin and retinol binding protein (two proteins synthesized both in fetal and adult liver) are expressed in the hepatoma cell lines HepG2 and Hep3B, but not in HeLa cells or fibroblasts. A DNA segment coding for haptoglobin (a protein synthesized only after birth) is only expressed in the hepatoma cell line HepG2 but not in Hep3B nor in non hepatic cell lines. The information for tissue specific expression is located in the 5' flanking region of all three genes. In vivo competition experiments show that these DNA segments bind to a common, apparently limiting, transacting factor. Conventional techniques (Bal deletions, site directed mutagenesis, etc.) have been used to precisely identify the DNA sequences responsible for these effects. The emerging picture is complex: they have identified multiple, separate transcriptional signals, essential for maximal promoter activation and tissue specific expression. Some of these signals show a negative effect on transcription in fibroblast cell lines.

  20. Selective insulin resistance in hepatocyte senescence

    International Nuclear Information System (INIS)

    Aravinthan, Aloysious; Challis, Benjamin; Shannon, Nicholas; Hoare, Matthew; Heaney, Judith; Alexander, Graeme J.M.

    2015-01-01

    Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance

  1. Selective insulin resistance in hepatocyte senescence

    Energy Technology Data Exchange (ETDEWEB)

    Aravinthan, Aloysious [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Challis, Benjamin [Institute of Metabolic Sciences, University of Cambridge, Cambridge (United Kingdom); Shannon, Nicholas [Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Hoare, Matthew [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Cancer Research UK Cambridge Institute, Cambridge (United Kingdom); Heaney, Judith [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom); Foundation for Liver Research, Institute of Hepatology, London (United Kingdom); Alexander, Graeme J.M., E-mail: gja1000@doctors.org.uk [Division of Gastroenterology and Hepatology, Department of Medicine, University of Cambridge, Cambridge (United Kingdom)

    2015-02-01

    Insulin resistance has been described in association with chronic liver disease for decades. Hepatocyte senescence has been demonstrated in chronic liver disease and as many as 80% of hepatocytes show a senescent phenotype in advanced liver disease. The aim of this study was to understand the role of hepatocyte senescence in the development of insulin resistance. Senescence was induced in HepG2 cells via oxidative stress. The insulin metabolic pathway was studied in control and senescent cells following insulin stimulation. GLUT2 and GLUT4 expressions were studied in HepG2 cells and human liver tissue. Further, GLUT2 and GLUT4 expressions were studied in three independent chronic liver disease cohorts. Signalling impairment distal to Akt in phosphorylation of AS160 and FoxO1 was evident in senescent HepG2 cells. Persistent nuclear localisation of FoxO1 was demonstrated in senescent cells despite insulin stimulation. Increased GLUT4 and decreased GLUT2 expressions were evident in senescent cells, human cirrhotic liver tissue and publically available liver disease datasets. Changes in GLUT expressions were associated with a poor clinical prognosis. In conclusion, selective insulin resistance is evident in senescent HepG2 cells and changes in GLUT expressions can be used as surrogate markers of hepatocyte senescence. - Highlights: • Senescent hepatocytes demonstrate selective insulin resistance. • GLUT changes act as markers of hepatocyte senescence and have prognostic value. • Study offers insight into long noticed intimacy of cirrhosis and insulin resistance.

  2. Possibility of Undifferentiated Human Thigh Adipose Stem Cells Differentiating into Functional Hepatocytes

    Directory of Open Access Journals (Sweden)

    Jong Hoon Lee

    2012-11-01

    Full Text Available BackgroundThis study aimed to investigate the possibility of isolating mesenchymal stem cells (MSCs from human thigh adipose tissue and the ability of human thigh adipose stem cells (HTASCs to differentiate into hepatocytes.MethodsThe adipose-derived stem cells (ADSCs were isolated from thigh adipose tissue. Growth factors, cytokines, and hormones were added to the collagen coated dishes to induce the undifferentiated HTASCs to differentiate into hepatocyte-like cells. To confirm the experimental results, the expression of hepatocyte-specific markers on undifferentiated and differentiated HTASCs was analyzed using reverse transcription polymerase chain reaction and immunocytochemical staining. Differentiation efficiency was evaluated using functional tests such as periodic acid schiff (PAS staining and detection of the albumin secretion level using enzyme-linked immunosorbent assay (ELISA.ResultsThe majority of the undifferentiated HTASCs were changed into a more polygonal shape showing tight interactions between the cells. The differentiated HTASCs up-regulated mRNA of hepatocyte markers. Immunocytochemical analysis showed that they were intensely stained with anti-albumin antibody compared with undifferentiated HTASCs. PAS staining showed that HTASCs submitted to the hepatocyte differentiation protocol were able to more specifically store glycogen than undifferentiated HTASCs, displaying a purple color in the cytoplasm of the differentiated HTASCs. ELISA analyses showed that differentiated HTASCs could secrete albumin, which is one of the hepatocyte markers.ConclusionsMSCs were islolated from human thigh adipose tissue differentiate to heapatocytes. The source of ADSCs is not only abundant abdominal adipose tissue, but also thigh adipose tissue for cell therapy in liver regeneration and tissue regeneration.

  3. Transcriptome of extracellular vesicles released by hepatocytes.

    Directory of Open Access Journals (Sweden)

    Felix Royo

    Full Text Available The discovery that the cells communicate through emission of vesicles has opened new opportunities for better understanding of physiological and pathological mechanisms. This discovery also provides a novel source for non-invasive disease biomarker research. Our group has previously reported that hepatocytes release extracellular vesicles with protein content reflecting the cell-type of origin. Here, we show that the extracellular vesicles released by hepatocytes also carry RNA. We report the messenger RNA composition of extracellular vesicles released in two non-tumoral hepatic models: primary culture of rat hepatocytes and a progenitor cell line obtained from a mouse foetal liver. We describe different subpopulations of extracellular vesicles with different densities and protein and RNA content. We also show that the RNA cargo of extracellular vesicles released by primary hepatocytes can be transferred to rat liver stellate-like cells and promote their activation. Finally, we provide in vitro and in vivo evidence that liver-damaging drugs galactosamine, acetaminophen, and diclofenac modify the RNA content of these vesicles. To summarize, we show that the extracellular vesicles secreted by hepatocytes contain various RNAs. These vesicles, likely to be involved in the activation of stellate cells, might become a new source for non-invasive identification of the liver toxicity markers.

  4. Long-term culture and expansion of primary human hepatocytes

    NARCIS (Netherlands)

    Levy, G.; Bomze, D.; Heinz, S.; Ramachandran, S.D.; Noerenberg, A.; Cohen, M.; Shibolet, O.; Sklan, E.; Braspenning, J.C.; Nahmias, Y.

    2015-01-01

    Hepatocytes have a critical role in metabolism, but their study is limited by the inability to expand primary hepatocytes in vitro while maintaining proliferative capacity and metabolic function. Here we describe the oncostatin M (OSM)-dependent expansion of primary human hepatocytes by low

  5. Swelling of rat hepatocytes stimulates glycogen synthesis

    NARCIS (Netherlands)

    Baquet, A.; Hue, L.; Meijer, A. J.; van Woerkom, G. M.; Plomp, P. J.

    1990-01-01

    In hepatocytes from fasted rats, several amino acids are known to stimulate glycogen synthesis via activation of glycogen synthase. The hypothesis that an increase in cell volume resulting from amino acid uptake may be involved in the stimulation of glycogen synthesis is supported by the following

  6. Metabolism of lipoproteins by human fetal hepatocytes

    International Nuclear Information System (INIS)

    Carr, B.R.

    1987-01-01

    The rate of clearance of lipoproteins from plasma appears to play a role in the development of atherogenesis. The liver may account for as much as two thirds of the removal of low-density lipoprotein and one third of the clearance of high-density lipoprotein in certain animal species and humans, mainly by receptor-mediated pathways. The purpose of the present investigation was to determine if human fetal hepatocytes maintained in vitro take up and degrade lipoproteins. We first determined that the maximal binding capacity of iodine 125-iodo-LDL was approximately 300 ng of low-density lipoprotein protein/mg of membrane protein and an apparent dissociation constant of approximately 60 micrograms low-density lipoprotein protein/ml in membranes prepared from human fetal liver. We found that the maximal uptake of [ 125 I]iodo-LDL and [ 125 I]iodo-HDL by fetal hepatocytes occurred after 12 hours of incubation. Low-density lipoprotein uptake preceded the appearance of degradation products by 4 hours, and thereafter the degradation of low-density lipoprotein increased linearly for at least 24 hours. In contrast, high-density lipoprotein was not degraded to any extent by fetal hepatocytes. [ 125 I]Iodo-LDL uptake and degradation were inhibited more than 75% by preincubation with low-density lipoprotein but not significantly by high-density lipoprotein, whereas [ 125 I]iodo-HDL uptake was inhibited 70% by preincubation with high-density lipoprotein but not by low-density lipoprotein. In summary, human fetal hepatocytes take up and degrade low-density lipoprotein by a receptor-mediated process similar to that described for human extrahepatic tissues

  7. Inhibition of hepatocyte gap junctional intercellular communication by tumor promoters

    International Nuclear Information System (INIS)

    Ruch, R.J.

    1988-01-01

    The mechanisms by which tumor promoters enhance neoplasia are poorly understood. One effect common to most tumor promoters is their ability to inhibit the cell-to-cell exchange of small molecules and ions through gap junctions, i.e., gap junctional intercellular communication (IC). IC maybe necessary for normal growth control and the loss of IC may predispose cells to enhanced growth. In the present studies, the effects of liver tumor promoters and other agents on IC between rodent hepatocytes in primary culture has been studied. IC was detected between hepatocytes: (1) autoradiographically following the passage and incorporation of [5- 3 H]uridine nucleotides from pre-labeled donor hepatocytes to non-labeled, adjacent recipient hepatocytes and (2) by fluorescence microscopy after microinjection of fluorescent Lucifer Yellow CH dye into hepatocytes and visualizing dye spread into adjacent hepatocytes

  8. Hepatocyte heterogeneity in the metabolism of carbohydrates.

    Science.gov (United States)

    Jungermann, K; Thurman, R G

    1992-01-01

    Periportal and perivenous hepatocytes possess different amounts and activities of the rate-generating enzymes of carbohydrate and oxidative energy metabolism and thus different metabolic capacities. This is the basis of the model of metabolic zonation, according to which periportal cells catalyze predominantly the oxidative catabolism of fatty and amino acids as well as glucose release and glycogen formation via gluconeogenesis, and perivenous cells carry out preferentially glucose uptake for glycogen synthesis and glycolysis coupled to liponeogenesis. The input of humoral and nervous signals into the periportal and perivenous zones is different; gradients of oxygen, substrates and products, hormones and mediators and nerve densities exist which are important not only for the short-term regulation of carbohydrate metabolism but also for the long-term regulation of zonal gene expression. The specialization of periportal and perivenous hepatocytes in carbohydrate metabolism has been well characterized. In vivo evidence is provided by the complex metabolic situation termed the 'glucose paradox' and by zonal flux differences calculated on the basis of the distribution of enzymes and metabolites. In vitro evidence is given by the different flux rates determined with classical invasive techniques, e.g. in periportal-like and perivenous-like hepatocytes in cell culture, in periportal- and perivenous-enriched hepatocyte populations and in perfused livers during orthograde and retrograde flow, as well as with noninvasive techniques using miniature oxygen electrodes, e.g. in livers perfused in either direction. Differences of opinion in the interpretation of studies with invasive and noninvasive techniques by the authors are discussed. The declining gradient in oxygen concentrations, the decreasing glucagon/insulin ratio and the different innervation could be important factors in the zonal expression of the genes of carbohydrate-metabolizing enzymes. While it is clear that

  9. Knockdown of autophagy enhances innate immune response in hepatitis C virus infected hepatocytes

    Science.gov (United States)

    Shrivastava, Shubham; Raychoudhuri, Amit; Steele, Robert; Ray, Ranjit; Ray, Ratna B.

    2010-01-01

    The role of autophagy in disease pathogenesis following viral infection is beginning to be elucidated. We have previously reported that hepatitis C virus (HCV) infection in hepatocytes induces autophagy. However, the biological significance of HCV induced autophagy has not been clarified. Autophagy has recently been identified as a novel component of innate immune system against viral infection. In the present study, we have shown that knockdown of autophagy related protein Beclin1 or ATG7 in immortalized human hepatocytes (IHH) inhibited HCV growth. Beclin1 or ATG7 knockdown IHH when infected with HCV exhibited an increased expression of IFN-β, OAS-1, IFN-α and IFI27 mRNAs of the interferon signaling pathways as compared to infection of control IHH. Subsequent study demonstrated that HCV infection in autophagy impaired IHH displayed caspase activation, PARP cleavage and apoptotic cell death. Conclusion The disruption of autophagy machinery in HCV infected hepatocytes activated IFN signaling pathway, and induced apoptosis. Together, these results suggest that HCV induced autophagy impairs innate immune response. PMID:21274862

  10. Immortalized human hepatocytes as a tool for the study of hepatocytic (de-)differentiation

    NARCIS (Netherlands)

    Schippers, IJ; Moshage, H; Roelofsen, H; Muller, M; Heymans, HSA; Ruiters, M; Kuipers, F

    Primary human hepatocytes were immortalized by stable transfection with a recombinant plasmid containing the early region of simian virus (SV) 40. The cells were cultured in serum-free, hormonally defined medium during the immortalization procedure. Foci of dividing cells were seen after 3 months.

  11. Stem Cells from Cryopreserved Human Dental Pulp Tissues Sequentially Differentiate into Definitive Endoderm and Hepatocyte-Like Cells in vitro.

    Science.gov (United States)

    Han, Young-Jin; Kang, Young-Hoon; Shivakumar, Sarath Belame; Bharti, Dinesh; Son, Young-Bum; Choi, Yong-Ho; Park, Won-Uk; Byun, June-Ho; Rho, Gyu-Jin; Park, Bong-Wook

    2017-01-01

    We previously described a novel tissue cryopreservation protocol to enable the safe preservation of various autologous stem cell sources. The present study characterized the stem cells derived from long-term cryopreserved dental pulp tissues (hDPSCs-cryo) and analyzed their differentiation into definitive endoderm (DE) and hepatocyte-like cells (HLCs) in vitro . Human dental pulp tissues from extracted wisdom teeth were cryopreserved as per a slow freezing tissue cryopreservation protocol for at least a year. Characteristics of hDPSCs-cryo were compared to those of stem cells from fresh dental pulps (hDPSCs-fresh). hDPSCs-cryo were differentiated into DE cells in vitro with Activin A as per the Wnt3a protocol for 6 days. These cells were further differentiated into HLCs in the presence of growth factors until day 30. hDPSCs-fresh and hDPSCs-cryo displayed similar cell growth morphology, cell proliferation rates, and mesenchymal stem cell character. During differentiation into DE and HLCs in vitro , the cells flattened and became polygonal in shape, and finally adopted a hepatocyte-like shape. The differentiated DE cells at day 6 and HLCs at day 30 displayed significantly increased DE- and hepatocyte-specific markers at the mRNA and protein level, respectively. In addition, the differentiated HLCs showed detoxification and glycogen storage capacities, indicating they could share multiple functions with real hepatocytes. These data conclusively show that hPDSCs-cryo derived from long-term cryopreserved dental pulp tissues can be successfully differentiated into DE and functional hepatocytes in vitro . Thus, preservation of dental tissues could provide a valuable source of autologous stem cells for tissue engineering.

  12. Hepatocyte nuclear factor 4A improves hepatic differentiation of immortalized adult human hepatocytes and improves liver function and survival.

    Science.gov (United States)

    Hang, Hua-Lian; Liu, Xin-Yu; Wang, Hai-Tian; Xu, Ning; Bian, Jian-Min; Zhang, Jian-Jun; Xia, Lei; Xia, Qiang

    2017-11-15

    Immortalized human hepatocytes (IHH) could provide an unlimited supply of hepatocytes, but insufficient differentiation and phenotypic instability restrict their clinical application. This study aimed to determine the role of hepatocyte nuclear factor 4A (HNF4A) in hepatic differentiation of IHH, and whether encapsulation of IHH overexpressing HNF4A could improve liver function and survival in rats with acute liver failure (ALF). Primary human hepatocytes were transduced with lentivirus-mediated catalytic subunit of human telomerase reverse transcriptase (hTERT) to establish IHH. Cells were analyzed for telomerase activity, proliferative capacity, hepatocyte markers, and tumorigenicity (c-myc) expression. Hepatocyte markers, hepatocellular functions, and morphology were studied in the HNF4A-overexpressing IHH. Hepatocyte markers and karyotype analysis were completed in the primary hepatocytes using shRNA knockdown of HNF4A. Nuclear translocation of β-catenin was assessed. Rat models of ALF were treated with encapsulated IHH or HNF4A-overexpressing IHH. A HNF4A-positive IHH line was established, which was non-tumorigenic and conserved properties of primary hepatocytes. HNF4A overexpression significantly enhanced mRNA levels of genes related to hepatic differentiation in IHH. Urea levels were increased by the overexpression of HNF4A, as measured 24h after ammonium chloride addition, similar to that of primary hepatocytes. Chromosomal abnormalities were observed in primary hepatocytes transfected with HNF4A shRNA. HNF4α overexpression could significantly promote β-catenin activation. Transplantation of HNF4A overexpressing IHH resulted in better liver function and survival of rats with ALF compared with IHH. HNF4A improved hepatic differentiation of IHH. Transplantation of HNF4A-overexpressing IHH could improve the liver function and survival in a rat model of ALF. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. The potential of induced pluripotent stem cell derived hepatocytes.

    Science.gov (United States)

    Hannoun, Zara; Steichen, Clara; Dianat, Noushin; Weber, Anne; Dubart-Kupperschmitt, Anne

    2016-07-01

    Orthotopic liver transplantation remains the only curative treatment for liver disease. However, the number of patients who die while on the waiting list (15%) has increased in recent years as a result of severe organ shortages; furthermore the incidence of liver disease is increasing worldwide. Clinical trials involving hepatocyte transplantation have provided encouraging results. However, transplanted cell function appears to often decline after several months, necessitating liver transplantation. The precise aetiology of the loss of cell function is not clear, but poor engraftment and immune-mediated loss appear to be important factors. Also, primary human hepatocytes (PHH) are not readily available, de-differentiate, and die rapidly in culture. Hepatocytes are available from other sources, such as tumour-derived human hepatocyte cell lines and immortalised human hepatocyte cell lines or porcine hepatocytes. However, all these cells suffer from various limitations such as reduced or differences in functions or risk of zoonotic infections. Due to their significant potential, one possible inexhaustible source of hepatocytes is through the directed differentiation of human induced pluripotent stem cells (hiPSCs). This review will discuss the potential applications and existing limitations of hiPSC-derived hepatocytes in regenerative medicine, drug screening, in vitro disease modelling and bioartificial livers. Copyright © 2016 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  14. Scintigraphic evidence of transplanted hepatocytes in spleen and liver

    International Nuclear Information System (INIS)

    Henne-Bruns, D.; Kremer, B.; Gramminger, K.; Broelsch, C.

    1986-01-01

    In rats suffering from hepatic enzymatic deficiency transplanted hepatocytes could be evidenced scintigraphically in liver, spleen and granulomas. In pigs, however, it is very difficult to demonstrate transplanted hepatocytes by scintiscanning because of the thickness of the tissues and the high background radiation in large animals

  15. Cell swelling and glycogen metabolism in hepatocytes from fasted rats

    NARCIS (Netherlands)

    Gustafson, L. A.; Jumelle-Laclau, M. N.; van Woerkom, G. M.; van Kuilenburg, A. B.; Meijer, A. J.

    1997-01-01

    Cell swelling is known to increase net glycogen production from glucose in hepatocytes from fasted rats by activating glycogen synthase. Since both active glycogen synthase and phosphorylase are present in hepatocytes, suppression of flux through phosphorylase may also contribute to the net increase

  16. Cytochrome P450IID6 recognized by LKM1 antibody is not exposed on the surface of hepatocytes.

    Science.gov (United States)

    Yamamoto, A M; Mura, C; De Lemos-Chiarandini, C; Krishnamoorthy, R; Alvarez, F

    1993-06-01

    LKM1 autoantibody, directed against P450IID6, is accepted as a marker of a particular type of autoimmune hepatitis, but its role in the pathogenesis of the disease is controversial. Localization of P450IID6 on the cell surface of rat hepatocytes was previously reported, suggesting that membrane-bound P450IID6 could be the target of LKM1 antibodies, thus allowing immune lysis of hepatocytes. The objective of the present study was to determine, using various methods, the cell localization of P450IID6 in human and rat hepatocytes. Incubation of rat and human hepatocytes with LKM1-positive serum showed slight, if any, cell membrane staining using immunofluorescence, immunoperoxidase and immunoelectron microscopic studies. No staining of the plasma membrane of human hepatocytes was observed when incubations were carried out with immunoaffinity-purified antibody directed against peptide 254-271, the main epitope of P450IID6 recognized by all LKM1 sera tested. Chinese hamster ovary cells, transfected with the complete P450IID6 cDNA and incubated with the supernatant from a B cell lymphoblastoid cell line prepared with the lymphocytes of a LKM1-positive patient, did not show any staining of the cell surface by immunofluorescence. Incubation of rat microsomal fraction vesicles with LKM1-positive serum, followed by protein A-gold immunoelectron microscopy, displayed a staining of almost all vesicles, confirming that P450IID6 is present on the cytoplasmic side of the microsomal membrane, which makes it unable to be expressed on the cell surface even if it were transported from the endoplasmic reticulum (ER). Sulpho NHS Biotin labelling of rat hepatocyte cell membranes did not show the presence of a 50-kD molecule that could have reacted with LKM1 antibody. DNA sequencing of exon 1 of the CYP2D6 gene of a patient positive for LKM1 antibody did not show any difference from that of the normal published sequence of the gene. This does not favour an alteration of the NH2 terminal

  17. Invisible Display in Aluminum

    DEFF Research Database (Denmark)

    Prichystal, Jan Phuklin; Hansen, Hans Nørgaard; Bladt, Henrik Henriksen

    2005-01-01

    Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish for an integ......Bang & Olufsen a/s has been working with ideas for invisible integration of displays in metal surfaces. Invisible integration of information displays traditionally has been possible by placing displays behind transparent or semitransparent materials such as plastic or glass. The wish...... for an integrated display in a metal surface is often ruled by design and functionality of a product. The integration of displays in metal surfaces requires metal removal in order to clear the area of the display to some extent. The idea behind an invisible display in Aluminum concerns the processing of a metal...

  18. Insulin suppresses the AMPK signaling pathway to regulate lipid metabolism in primary cultured hepatocytes of dairy cows.

    Science.gov (United States)

    Li, Xinwei; Li, Yu; Ding, Hongyan; Dong, Jihong; Zhang, Renhe; Huang, Dan; Lei, Lin; Wang, Zhe; Liu, Guowen; Li, Xiaobing

    2018-05-01

    Dairy cows with type II ketosis display hepatic fat accumulation and hyperinsulinemia, but the underlying mechanism is not completely clear. This study aimed to clarify the regulation of lipid metabolism by insulin in cow hepatocytes. In vitro, cow hepatocytes were treated with 0, 1, 10, or 100 nm insulin in the presence or absence of AICAR (an AMP-activated protein kinase alpha (AMPKα) activator). The results showed that insulin decreased AMPKα phosphorylation. This inactivation of AMPKα increased the gene and protein expression levels of carbohydrate responsive element-binding protein (ChREBP) and sterol regulatory element-binding protein-1c (SREBP-1c), which downregulated the expression of lipogenic genes, thereby decreasing lipid biosynthesis. Furthermore, AMPKα inactivation decreased the gene and protein expression levels of peroxisome proliferator-activated receptor-α (PPARα), which upregulated the expression of lipid oxidation genes, thereby increasing lipid oxidation. In addition, insulin decreased the very low density lipoprotein (VLDL) assembly. Consequently, triglyceride content was significantly increased in insulin treated hepatocytes. Activation of AMPKα induced by AICAR could reverse the effect of insulin on PPARα, SREBP-1c, and ChREBP, thereby decreasing triglyceride content. These results indicate that insulin inhibits the AMPKα signaling pathway to increase lipid synthesis and decrease lipid oxidation and VLDL assembly in cow hepatocytes, thereby inducing TG accumulation. This mechanism could partly explain the causal relationship between hepatic fat accumulation and hyperinsulinemia in dairy cows with type II ketosis.

  19. Ketose induced respiratory inhibition in isolated hepatocytes.

    Science.gov (United States)

    Martínez, P; Carrascosa, J M; Núñez de Castro, I

    1987-06-01

    The addition of 10 mM fructose or 10 mM tagatose to a suspension of hepatocytes caused respiratory inhibition, whereas no change in oxygen uptake was observed following the addition of glucose. However, incubations in the presence of fructose showed a high, aerobic glycolytic activity. Tagatose is phosphorylated to tagatose 1-phosphate but is not further metabolized by cell free liver extract. Moreover, the addition of fructose to glucagon treated cells also caused the Crabtree-like effect. The concentration of adenine nucleotides and inorganic phosphate (Pi) in the mitochondrial and cytosolic compartments during incubation (time 30 min) was determined by the digitonin fractionation procedure. In the presence of 10 mM fructose or tagatose, the total adenine nucleotide pools decreased by 40%; however, glucose produced no change. The addition of ketoses diminished the asymmetric distribution of extramitochondrial (ATP/ADP)e ratio and intramitochondrial (ATP/ADP)i ratio. At the same time the total mitochondrial Pi fell from 17 mM to 6-7 mM. The mitochondrial membrane potential (-161 mV) in the presence of fructose showed no changes during the 30 min experimental period. An increase in the NADH/NAD+ ratio was observed. These results suggest that in hepatocytes the inhibition of respiration is not necessarily linked with the enhanced aerobic glycolysis, by competition for common substrates.

  20. Insulin internalization in isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Galan, J.; Trankina, M.; Noel, R.; Ward, W.

    1990-01-01

    This project was designed to determine whether neomycin, an aminoglycoside antibiotic, has a significant effect upon the pathways of ligand endocytosis in isolated rat hepatocytes. The pathways studied include receptor-mediated endocytosis and fluid-phase endocytosis. Neomycin causes a dose-dependent acceleration of 125 I-insulin internalization. Since fluid-phase endocytosis can also be a significant factor in 125 I-insulin internalization, lucifer yellow (LY), a marker for fluid-phase endocytosis, was incorporated into an assay similar to the 125 I-insulin internalization procedure. In the presence of 5 mM neomycin, a significant increase in LY uptake was evident at 0.2 and 0.4 mg/ml of LY. At 0.8 mg/ml, a decrease in LY uptake was observed. The increased rate of 125 I-insulin internalization in the presence of neomycin was intriguing. Since one action of neomycin is to inhibit phosphoinositidase C, it suggests that the phosphotidylinositol cycle may be involved in ligand internalization by hepatocytes. At low insulin concentrations, receptor-mediated uptake predominates. Fluid-phase uptake can become an important uptake route as insulin concentrations are increased. Since neomycin stimulates fluid-phase endocytosis, it must also be taken into account when measuring ligand internalization

  1. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes

    International Nuclear Information System (INIS)

    Sanada, Takahiro; Tsukiyama-Kohara, Kyoko; Yamamoto, Naoki; Ezzikouri, Sayeh; Benjelloun, Soumaya; Murakami, Shuko; Tanaka, Yasuhito; Tateno, Chise; Kohara, Michinori

    2016-01-01

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3–6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10"5 copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10"4-10"6 copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10"3 copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. - Highlights: • Primary hepatocytes were established from tupaia that is a novel HBV infection model. • Tupaia primary hepatocytes were susceptible for HBV infection. • The immunodeficient chimeric mice with tupaia hepatocytes were established. • The chimeric mice with tupaia hepatocytes were susceptible for HBV infection.

  2. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Sanada, Takahiro [Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506 (Japan); Tsukiyama-Kohara, Kyoko, E-mail: kkohara@vet.kagoshima-u.ac.jp [Transboundary Animal Diseases Centre, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24, Korimoto, Kagoshima-city, Kagoshima 890-0065 (Japan); Laboratory of Animal Hygiene, Joint Faculty of Veterinary Medicine, Kagoshima University, 1-21-24, Korimoto, Kagoshima, Kagoshima 890-0065 (Japan); Yamamoto, Naoki [Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506 (Japan); Ezzikouri, Sayeh; Benjelloun, Soumaya [Viral Hepatitis Laboratory, Virology Unit, Institut Pasteur du Maroc, 1, Louis Pasteur, Casablanca 20360 (Morocco); Murakami, Shuko; Tanaka, Yasuhito [Department of Virology and Liver Unit, Nagoya City University Graduate School of Medical Sciences, Kawasumi 1, Mizuho-ku, Nagoya, Aichi 467-8601 (Japan); Tateno, Chise [PhoenixBio Co. Ltd., 3-4-1, Kagamiyama, Higashi-Hiroshima, Hiroshima 739-0046 (Japan); Kohara, Michinori, E-mail: kohara-mc@igakuken.or.jp [Department of Microbiology and Cell Biology, Tokyo Metropolitan Institute of Medical Science, 2-1-6, Kamikitazawa, Setagaya-ku, Tokyo 156-8506 (Japan)

    2016-01-08

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3–6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10{sup 5} copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10{sup 4}-10{sup 6} copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10{sup 3} copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. - Highlights: • Primary hepatocytes were established from tupaia that is a novel HBV infection model. • Tupaia primary hepatocytes were susceptible for HBV infection. • The immunodeficient chimeric mice with tupaia hepatocytes were established. • The chimeric mice with tupaia hepatocytes were susceptible for HBV infection.

  3. European display scene

    Science.gov (United States)

    Bartlett, Christopher T.

    2000-08-01

    The manufacture of Flat Panel Displays (FPDs) is dominated by Far Eastern sources, particularly in Active Matrix Liquid Crystal Displays (AMLCD) and Plasma. The United States has a very powerful capability in micro-displays. It is not well known that Europe has a very active research capability which has lead to many innovations in display technology. In addition there is a capability in display manufacturing of organic technologies as well as the licensed build of Japanese or Korean designs. Finally, Europe has a display systems capability in military products which is world class.

  4. Handbook of display technology

    CERN Document Server

    Castellano, Joseph A

    1992-01-01

    This book presents a comprehensive review of technical and commercial aspects of display technology. It provides design engineers with the information needed to select proper technology for new products. The book focuses on flat, thin displays such as light-emitting diodes, plasma display panels, and liquid crystal displays, but it also includes material on cathode ray tubes. Displays include a large number of products from televisions, auto dashboards, radios, and household appliances, to gasoline pumps, heart monitors, microwave ovens, and more.For more information on display tech

  5. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix; Gregson, James; Wetzstein, Gordon; Raskar, Ramesh; Heidrich, Wolfgang

    2014-01-01

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  6. A Compressive Superresolution Display

    KAUST Repository

    Heide, Felix

    2014-06-22

    In this paper, we introduce a new compressive display architecture for superresolution image presentation that exploits co-design of the optical device configuration and compressive computation. Our display allows for superresolution, HDR, or glasses-free 3D presentation.

  7. Hepatocyte growth factor profile with breast cancer

    Directory of Open Access Journals (Sweden)

    Hoda A EL-Attar

    2011-01-01

    Full Text Available Background: The multifunctional hepatocyte growth factor (HGF is the ligand of c-Met receptor; it plays important role in mammary differentiation. HGF-Met signaling is a critical downstream function of c-Src-Stat3 pathway in mammalian tumorigenesis. Aim: Evaluation of tissue c-Met receptor hepatocyte growth factor receptor (HGFR and serum level of HGF in female breast ductal carcinoma. Materials and Methods: Sixty-eight premenopausal females were divided as 30 control females subdivided into: [Group 1] 15 healthy volunteer females and [Group 2] five with fibrocystic disease and 10 having fibroadenoma of the breast and patients group [Group 3] consisted of 38 female patients with breast ductal carcinoma. Thorough clinical examination, preoperative fine needle aspiration cytology, estimation of fasting serum glucose, urea, creatinine, and uric acid levels, alanine aminotransferase activities, C-reactive protein, HGF level, before surgery and histopathological examination of the breast masses, and immunohistochemical detection of HGFR were done. Results and Conclusions: Significant increase in serum HGF levels were found in patients with breast cancer as compared with controls. Significant increase was also seen in patients with breast cancer with and without lymph node metastasis when each subgroup was compared with controls. Serum level of HGF is an independent prognostic indicator of breast cancer. Fibrocystic disease of the breast showed weak HGFR expression, while in normal tissue, HGFR was scanty; meanwhile, breast invasive ductal carcinoma showed homogenous strong reaction to HGFR. HGF is only one of a number of key factors involved in breast cancer and preoperative high serum HGF levels and malignancy occur usually together.

  8. Liquid crystal display

    International Nuclear Information System (INIS)

    Takami, K.

    1981-01-01

    An improved liquid crystal display device is described which can display letters, numerals and other necessary patterns in the night time using a minimized amount of radioactive material. To achieve this a self-luminous light source is placed in a limited region corresponding to a specific display area. (U.K.)

  9. Transcription factors ETF, E2F, and SP-1 are involved in cytokine-independent proliferation of murine hepatocytes.

    Science.gov (United States)

    Zellmer, Sebastian; Schmidt-Heck, Wolfgang; Godoy, Patricio; Weng, Honglei; Meyer, Christoph; Lehmann, Thomas; Sparna, Titus; Schormann, Wiebke; Hammad, Seddik; Kreutz, Clemens; Timmer, Jens; von Weizsäcker, Fritz; Thürmann, Petra A; Merfort, Irmgard; Guthke, Reinhard; Dooley, Steven; Hengstler, Jan G; Gebhardt, Rolf

    2010-12-01

    The cellular basis of liver regeneration has been intensely investigated for many years. However, the mechanisms initiating hepatocyte "plasticity" and priming for proliferation are not yet fully clear. We investigated alterations in gene expression patterns during the first 72 hours of C57BL/6N mouse hepatocyte culture on collagen monolayers (CM), which display a high basal frequency of proliferation in the absence of cytokines. Although many metabolic genes were down-regulated, genes related to mitogen-activated protein kinase (MAPK) signaling and cell cycle were up-regulated. The latter genes showed an overrepresentation of transcription factor binding sites (TFBS) for ETF (TEA domain family member 2), E2F1 (E2F transcription factor 1), and SP-1 (Sp1 transcription factor) (P ETF, E2F1, and SP-1 and displayed increased expression of E2F1. Cultivation of murine hepatocytes on CM primes cells for proliferation through cytokine-independent activation of MAPK signaling. The transcription factors ETF, E2F1, and SP-1 seem to play a pronounced role in mediating proliferation-dependent differential gene expression. Similar events, but on a shorter time-scale, occur very early after liver damage in vivo. Copyright © 2010 American Association for the Study of Liver Diseases.

  10. Liquid Crystal Airborne Display

    Science.gov (United States)

    1977-08-01

    Cum.nings, J. P., et al., Properties and Limitations oe Liquid Crystals for Aircraft Displays, Honeywell Corporate Researc ."I Center, Final Report HR-72...basic module could be used to build displays for both the commercial and military! 157- marhecs, and so would establi sh a broad and sizable market ... market for the display becomes a reality; therein lies, f TABLE 16 THE COURSE OF FUTURE DISPLAY DEVELOPMENT Today 1976-77 1980 1985 Display Size 2" 1 3.2

  11. Phenotypic and functional analyses show stem cell-derived hepatocyte-like cells better mimic fetal rather than adult hepatocytes.

    Science.gov (United States)

    Baxter, Melissa; Withey, Sarah; Harrison, Sean; Segeritz, Charis-Patricia; Zhang, Fang; Atkinson-Dell, Rebecca; Rowe, Cliff; Gerrard, Dave T; Sison-Young, Rowena; Jenkins, Roz; Henry, Joanne; Berry, Andrew A; Mohamet, Lisa; Best, Marie; Fenwick, Stephen W; Malik, Hassan; Kitteringham, Neil R; Goldring, Chris E; Piper Hanley, Karen; Vallier, Ludovic; Hanley, Neil A

    2015-03-01

    Hepatocyte-like cells (HLCs), differentiated from pluripotent stem cells by the use of soluble factors, can model human liver function and toxicity. However, at present HLC maturity and whether any deficit represents a true fetal state or aberrant differentiation is unclear and compounded by comparison to potentially deteriorated adult hepatocytes. Therefore, we generated HLCs from multiple lineages, using two different protocols, for direct comparison with fresh fetal and adult hepatocytes. Protocols were developed for robust differentiation. Multiple transcript, protein and functional analyses compared HLCs to fresh human fetal and adult hepatocytes. HLCs were comparable to those of other laboratories by multiple parameters. Transcriptional changes during differentiation mimicked human embryogenesis and showed more similarity to pericentral than periportal hepatocytes. Unbiased proteomics demonstrated greater proximity to liver than 30 other human organs or tissues. However, by comparison to fresh material, HLC maturity was proven by transcript, protein and function to be fetal-like and short of the adult phenotype. The expression of 81% phase 1 enzymes in HLCs was significantly upregulated and half were statistically not different from fetal hepatocytes. HLCs secreted albumin and metabolized testosterone (CYP3A) and dextrorphan (CYP2D6) like fetal hepatocytes. In seven bespoke tests, devised by principal components analysis to distinguish fetal from adult hepatocytes, HLCs from two different source laboratories consistently demonstrated fetal characteristics. HLCs from different sources are broadly comparable with unbiased proteomic evidence for faithful differentiation down the liver lineage. This current phenotype mimics human fetal rather than adult hepatocytes. Copyright © 2014 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  12. Displays in scintigraphy

    International Nuclear Information System (INIS)

    Todd-Pokropek, A.E.; Pizer, S.M.

    1977-01-01

    Displays have several functions: to transmit images, to permit interaction, to quantitate features and to provide records. The main characteristics of displays used for image transmission are their resolution, dynamic range, signal-to-noise ratio and uniformity. Considerations of visual acuity suggest that the display element size should be much less than the data element size, and in current practice at least 256X256 for a gamma camera image. The dynamic range for image transmission should be such that at least 64 levels of grey (or equivalent) are displayed. Scanner displays are also considered, and in particular, the requirements of a whole-body camera are examined. A number of display systems and devices are presented including a 'new' heated object colour display system. Interaction with displays is considered, including background subtraction, contrast enhancement, position indication and region-of-interest generation. Such systems lead to methods of quantitation, which imply knowledge of the expected distributions. Methods for intercomparing displays are considered. Polaroid displays, which have for so long dominated the field, are in the process of being replaced by stored image displays, now that large cheap memories exist which give an equivalent image quality. The impact of this in nuclear medicine is yet to be seen, but a major effect will be to enable true quantitation. (author)

  13. Hepatocyte-specific deletion of the keap1 gene activates Nrf2 and confers potent resistance against acute drug toxicity

    International Nuclear Information System (INIS)

    Okawa, Hiromi; Motohashi, Hozumi; Kobayashi, Akira; Aburatani, Hiroyuki; Kensler, Thomas W.; Yamamoto, Masayuki

    2006-01-01

    Nrf2 is a key regulator of many detoxifying enzyme genes, and cytoplasmic protein Keap1 represses the Nrf2 activity under quiescent conditions. Germ line deletion of the keap1 gene results in constitutive activation of Nrf2, but the pups unexpectedly died before weaning. To investigate how constitutive activation of Nrf2 influences the detoxification system in adult mice, we generated mice bearing a hepatocyte-specific disruption of the keap1 gene. Homozygous mice were viable and their livers displayed no apparent abnormalities, but nuclear accumulation of Nrf2 is elevated. Microarray analysis revealed that, while many detoxifying enzyme genes are highly expressed, some of the typical Nrf2-dependent genes are only marginally increased in the Keap1-deficient liver. The mutant mice were significantly more resistant to toxic doses of acetaminophen than control animals. These results demonstrate that chronic activation of Nrf2 confers animals with resistance to xenobiotics without affecting the morphological and physiological integrity of hepatocytes

  14. RNA synthesis in primary cultures of adult rat hepatocytes

    International Nuclear Information System (INIS)

    Fugassa, E.; Gallo, G.; Voci, A.; Cordone, A.

    1983-01-01

    The ability of hepatocyte monolayers to synthesize RNA was investigated by measuring [3H]orotic acid incorporation into RNA and the total nuclear RNA polymerase activity as a function of the time in culture. The results demonstrate that primary cultures of hepatocytes maintained in a chemically defined serum- and hormone-free medium are able to synthesize RNA actively. This ability increases within the first 2 d of culture, despite the concomitant decrease in [3H]orotic acid uptake, and decreases only after 3 d. Factors such as serum, insulin, and dexamethasone, known to improve maintenance of functional hepatocytes, markedly stimulate the uptake of labeled precursor without apparently affecting the rate of RNA synthesis by cultured cells. It is suggested that the culture of adult rat hepatocytes provides a useful experimental model for the studies of hormonal regulation of transcription in liver

  15. Metabolism of para-aminophenol by rat hepatocytes.

    Science.gov (United States)

    Yan, Z; Nikelly, J G; Killmer, L; Tarloff, J B

    2000-08-01

    Autoxidation of para-aminophenol (PAP) has been proposed to account for the selective nephrotoxicity of this compound. However, other studies suggest that hepatic metabolites of PAP rather than the parent compound may be responsible for renal damage. These studies were designed to investigate PAP metabolism in isolated hepatocytes. We synthesized several proposed metabolites for analysis by HPLC/mass spectrometry and compared those results with HPLC/mass spectrometric analyses of metabolites found after incubating hepatocytes with PAP. Hepatocytes prepared from male Sprague-Dawley rats were incubated in Krebs-Henseleit buffer at 37 degrees C for 5 h with 2.3 mM PAP under an atmosphere of 5% CO2/95% O2. Aliquots were withdrawn at 0.1 h of incubation and then hourly through 5 h of incubation. Reactions were terminated by the addition of acetonitrile. Hepatocyte viability was unaltered with PAP present in the incubation medium. We found that hepatocytes converted PAP to two major metabolites (PAP-GSH conjugates and PAP-N-acetylcysteine conjugates) and several minor metabolites [PAP-O-glucuronide, acetaminophen (APAP), APAP-O-glucuronide, APAP-GSH conjugates, and 4-hydroxyformanilide]. Preincubating hepatoyctes with 1-aminobenzotriazole, an inhibitor of cytochromes P450, did not alter the pattern of PAP metabolism. In conclusion, we found that PAP was metabolized in hepatocytes predominantly to PAP-GSH conjugates and PAP-N-acetylcysteine conjugates in sufficient quantities to account for the nephrotoxicity of PAP.

  16. Hepatocyte polyploidization and its association with pathophysiological processes.

    Science.gov (United States)

    Wang, Min-Jun; Chen, Fei; Lau, Joseph T Y; Hu, Yi-Ping

    2017-05-18

    A characteristic cellular feature of the mammalian liver is the progressive polyploidization of the hepatocytes, where individual cells acquire more than two sets of chromosomes. Polyploidization results from cytokinesis failure that takes place progressively during the course of postnatal development. The proportion of polyploidy also increases with the aging process or with cellular stress such as surgical resection, toxic stimulation, metabolic overload, or oxidative damage, to involve as much as 90% of the hepatocytes in mice and 40% in humans. Hepatocyte polyploidization is generally considered an indicator of terminal differentiation and cellular senescence, and related to the dysfunction of insulin and p53/p21 signaling pathways. Interestingly, the high prevalence of hepatocyte polyploidization in the aged mouse liver can be reversed when the senescent hepatocytes are serially transplanted into young mouse livers. Here we review the current knowledge on the mechanism of hepatocytes polyploidization during postnatal growth, aging, and liver diseases. The biologic significance of polyploidization in senescent reversal, within the context of new ways to think of liver aging and liver diseases is considered.

  17. Functional assessment of hepatocytes after transplantation into rat spleen

    International Nuclear Information System (INIS)

    Woods, R.J.; Fuller, B.J.; Attenburrow, V.D.; Nutt, L.H.; Hobbs, K.E.

    1982-01-01

    The retention of structural integrity and metabolic function by isolated hepatocytes after ectopic transplantation has been investigated in autografted rats. Rats were partially hepatectomized and isolated hepatocytes prepared from the excised liver lobes were implanted into their spleens. Histological examination of the spleens 7 or more weeks after implantation revealed aggregates of hepatocytes in the red pulp. Two tests of biochemical function were applied to the hepatocytes after transplantation. In the first the hepatobiliary imaging agent technetium-99m N-[N'-(2, 6-dimethylphenyl)carbamoylmethyl]iminodiacetic acid (99mTc HIDA), which was shown to be avidly taken up by isolated hepatocytes in vitro, was infused into the tail veins of autograft and control rats. Radioactivity accumulating in the spleens of autografted rats was markedly greater than that in controls implanted with lethally damaged cells or in nontransplanted rats. In the second the presence of bilirubin metabolites was sought in autograft spleens after intravenous infusion of bilirubin. Both mono- and diglucuronides of bilirubin were recovered from the spleens of autograft rats but no conjugates were recovered from the spleens of unoperated controls. We conclude that after autotransplantation isolated hepatocytes retain their morphology and at least some of their functional activities

  18. alpha-Amanitin induced apoptosis in primary cultured dog hepatocytes.

    Directory of Open Access Journals (Sweden)

    Adam Szelag

    2010-06-01

    Full Text Available Amatoxin poisoning is caused by mushroom species belonging to the genera Amanita, Galerina and Lepiota with the majority of lethal mushroom exposures attributable to Amanita phalloides. High mortality rate in intoxications with these mushrooms is principally a result of the acute liver failure following significant hepatocyte damage due to hepatocellular uptake of amatoxins. A wide variety of amatoxins have been isolated; however, alpha-amanitin (alpha-AMA appears to be the primary toxin. Studies in vitro and in vivo suggest that alpha-AMA does not only cause hepatocyte necrosis, but also may lead to apoptotic cell death. The objective of this study was to evaluate the complex hepatocyte apoptosis in alpha-AMA cytotoxicity. All experiments were performed on primary cultured canine hepatocytes. The cells were incubated for 12 h with alpha-AMA at a final concentration of 1, 5, 10 and 20 microM. Viability test (MTT assay, apoptosis evaluation (TUNEL reaction, detection of DNA laddering and electron microscopy were performed at 6 and 12 h of exposure to alpha-AMA. There was a clear correlation between hepatocyte viability, concentration of alpha-AMA and time of exposure to this toxin. The decline in cultured dog hepatocyte viability during the exposure to alpha-AMA is most likely preceded by enhanced cellular apoptosis. Our results demonstrate that apoptosis might contribute to pathogenesis of the severe liver injury in the course of amanitin intoxication, particularly during the early phase of poisoning.

  19. OLED displays and lighting

    CERN Document Server

    Koden, Mitsuhiro

    2017-01-01

    Organic light-emitting diodes (OLEDs) have emerged as the leading technology for the new display and lighting market. OLEDs are solid-state devices composed of thin films of organic molecules that create light with the application of electricity. OLEDs can provide brighter, crisper displays on electronic devices and use less power than conventional light-emitting diodes (LEDs) or liquid crystal displays (LCDs) used today. This book covers both the fundamentals and practical applications of flat and flexible OLEDs.

  20. Scalable Resolution Display Walls

    KAUST Repository

    Leigh, Jason; Johnson, Andrew; Renambot, Luc; Peterka, Tom; Jeong, Byungil; Sandin, Daniel J.; Talandis, Jonas; Jagodic, Ratko; Nam, Sungwon; Hur, Hyejung; Sun, Yiwen

    2013-01-01

    This article will describe the progress since 2000 on research and development in 2-D and 3-D scalable resolution display walls that are built from tiling individual lower resolution flat panel displays. The article will describe approaches and trends in display hardware construction, middleware architecture, and user-interaction design. The article will also highlight examples of use cases and the benefits the technology has brought to their respective disciplines. © 1963-2012 IEEE.

  1. JAVA Stereo Display Toolkit

    Science.gov (United States)

    Edmonds, Karina

    2008-01-01

    This toolkit provides a common interface for displaying graphical user interface (GUI) components in stereo using either specialized stereo display hardware (e.g., liquid crystal shutter or polarized glasses) or anaglyph display (red/blue glasses) on standard workstation displays. An application using this toolkit will work without modification in either environment, allowing stereo software to reach a wider audience without sacrificing high-quality display on dedicated hardware. The toolkit is written in Java for use with the Swing GUI Toolkit and has cross-platform compatibility. It hooks into the graphics system, allowing any standard Swing component to be displayed in stereo. It uses the OpenGL graphics library to control the stereo hardware and to perform the rendering. It also supports anaglyph and special stereo hardware using the same API (application-program interface), and has the ability to simulate color stereo in anaglyph mode by combining the red band of the left image with the green/blue bands of the right image. This is a low-level toolkit that accomplishes simply the display of components (including the JadeDisplay image display component). It does not include higher-level functions such as disparity adjustment, 3D cursor, or overlays all of which can be built using this toolkit.

  2. Displays and simulators

    Science.gov (United States)

    Mohon, N.

    A 'simulator' is defined as a machine which imitates the behavior of a real system in a very precise manner. The major components of a simulator and their interaction are outlined in brief form, taking into account the major components of an aircraft flight simulator. Particular attention is given to the visual display portion of the simulator, the basic components of the display, their interactions, and their characteristics. Real image displays are considered along with virtual image displays, and image generators. Attention is given to an advanced simulator for pilot training, a holographic pancake window, a scan laser image generator, the construction of an infrared target simulator, and the Apollo Command Module Simulator.

  3. Force spectroscopy of hepatocytic extracellular matrix components

    Energy Technology Data Exchange (ETDEWEB)

    Yongsunthon, R., E-mail: YongsuntR@Corning.com [Corning Incorporated, SP-FR-01, R1S32D, Corning, NY 14831 (United States); Baker, W.A.; Bryhan, M.D.; Baker, D.E.; Chang, T.; Petzold, O.N.; Walczak, W.J.; Liu, J.; Faris, R.A.; Senaratne, W.; Seeley, L.A.; Youngman, R.E. [Corning Incorporated, SP-FR-01, R1S32D, Corning, NY 14831 (United States)

    2009-07-15

    We present atomic force microscopy and force spectroscopy data of live hepatocytes (HEPG2/C3A liver cell line) grown in Eagle's Minimum Essential Medium, a complex solution of salts and amino acids commonly used for cell culture. Contact-mode imaging and force spectroscopy of this system allowed correlation of cell morphology and extracellular matrix (ECM) properties with substrate properties. Force spectroscopy analysis of cellular 'footprints' indicated that the cells secrete large polymers (e.g., 3.5 {mu}m contour length and estimated MW 1000 kDa) onto their substrate surface. Although definitive identification of the polymers has not yet been achieved, fluorescent-labeled antibody staining has specified the presence of ECM proteins such as collagen and laminin in the cellular footprints. The stretched polymers appear to be much larger than single molecules of known ECM components, such as collagen and heparan sulfate proteoglycan, thus suggesting that the cells create larger entangled, macromolecular structures from smaller components. There is strong evidence which suggests that the composition of the ECM is greatly influenced by the hydrophobicity of the substrate surface, with preferential production and/or adsorption of larger macromolecules on hydrophobic surfaces.

  4. Displays enabling mobile multimedia

    Science.gov (United States)

    Kimmel, Jyrki

    2007-02-01

    With the rapid advances in telecommunications networks, mobile multimedia delivery to handsets is now a reality. While a truly immersive multimedia experience is still far ahead in the mobile world, significant advances have been made in the constituent audio-visual technologies to make this become possible. One of the critical components in multimedia delivery is the mobile handset display. While such alternatives as headset-style near-to-eye displays, autostereoscopic displays, mini-projectors, and roll-out flexible displays can deliver either a larger virtual screen size than the pocketable dimensions of the mobile device can offer, or an added degree of immersion by adding the illusion of the third dimension in the viewing experience, there are still challenges in the full deployment of such displays in real-life mobile communication terminals. Meanwhile, direct-view display technologies have developed steadily, and can provide a development platform for an even better viewing experience for multimedia in the near future. The paper presents an overview of the mobile display technology space with an emphasis on the advances and potential in developing direct-view displays further to meet the goal of enabling multimedia in the mobile domain.

  5. Visual merchandising window display

    Directory of Open Access Journals (Sweden)

    Opris (Cas. Stanila M.

    2013-12-01

    Full Text Available Window display plays a major part in the selling strategies; it does not only include the simple display of goods, nowadays it is a form of art, also having the purpose of sustaining the brand image. This article wants to reveal the tools that are essential in creating a fabulous window display. Being a window designer is not an easy job, you have to always think ahead trends, to have a sense of colour, to know how to use light to attract customers in the store after only one glance at the window. The big store window displays are theatre scenes: with expensive backgrounds, special effects and high fashion mannequins. The final role of the displays is to convince customers to enter the store and trigger the purchasing act which is the final goal of the retail activity.

  6. Role of macrophages in the immune response to hepatocytes

    International Nuclear Information System (INIS)

    Bumgardner, G.L.; Chen, S.; Almond, S.P.; Ascher, N.L.; Payne, W.D.; Matas, A.J.

    1990-01-01

    The purpose of this study was to determine the role of host macrophages in the development of allospecific cytolytic T cells (allo-CTLs) in response to purified allogeneic MHC Class I+, Class II- hepatocytes in vivo in hepatocyte sponge matrix allografts (HC-SMA). Depletion of antigen-presenting cells (APCs) from responder splenocytes in mixed lymphocyte hepatocyte culture (MLHC) inhibits the development of allo-CTLs in response to purified hepatocytes. First the ability of sponge macrophages to function as accessory cells in indirect presentation of hepatocyte Class I antigen was tested in MLHC. We found that addition of irradiated sponge cells (a source of sponge macrophages) restored the development of allo-CTLs in MLHC depleted of responder APCs. Therefore, radioresistant sponge macrophages can function as accessory cells in MLHC. We next employed silica as an immunotherapy targeted against host macrophages and assessed the effect on development of allo-CTLs in HC-SMA. We found that local (intrasponge) silica treatment completely inhibited the development of allo-CTLs in HC-SMA. Combined local and systemic silica treatment resulted in inhibition of allocytotoxicity comparable to local silica treatment alone in the doses tested. We conclude that host macrophages which infiltrate HC-SMA can function as accessory cells in vitro in MLHC and that both infiltrating host macrophages and lymphocytes participate in the development of an alloimmune response to purified hepatocytes in vivo. This interaction may involve indirect antigen presentation of hepatocyte Class I antigen by macrophages to host lymphocytes which accumulate in HC-SMA

  7. Effects of edaravone, a radical scavenger, on hepatocyte transplantation.

    Science.gov (United States)

    Hayashi, Chihiro; Ito, Masahiro; Ito, Ryoutaro; Murakumo, Akiko; Yamamoto, Naoki; Hiramatsu, Noriko; Fox, Ira J; Horiguchi, Akihiko

    2014-12-01

    Hepatocyte transplantation (HTx) has yielded significant improvements in liver function and survival in experimentally induced acute liver failure and liver-based metabolic disease. However, transplantation is inefficient, and it is thought that transplanted hepatocytes have a shortened lifespan because of inflammation involving excess nitric oxide (NO). The present study aimed to clarify whether edaravone, a free radical scavenger used to treat ischemic stroke, could reduce ischemic changes in hepatocyte-transplanted livers. Edaravone (3 mg/kg) was administered intravenously 24 h before HTx to Nagase analbuminemic rats (NARs). Hepatocytes were isolated, and 30 × 10(6) cells were injected in a 1.0-ml volume directly into the spleens of NARs. All experimental groups studied received FK506 to control rejection. Animals in Group A received medium-only; Group B received HTx only; and Group C received HTx and edaravone. Forty-eight hours after transplantation, the hepatocytes from animals were isolated and analyzed for staining with propidium iodide- and annexin-V using flow cytometry. Liver sections were also studied by immunostaining for albumin, and TUNEL. Peripheral blood serum albumin levels were measured on post-transplant days 0, 3, 5, 7, 10 and 14 using ELISA. The edaravone-treated animals demonstrated an increased number of engrafted donor hepatocytes in the liver. The edaravone-treated liver sections also contained fewer TUNEL-positive cells and animals that received edaravone had higher serum albumin levels post-transplantation. Hepatocytes were also found to have increased in numbers 2 weeks following treatment with edaravone. Edaravone administration during HTx can suppress apoptosis near the transplanted cells, increasing engraftment. These studies indicate its potential usefulness for future clinical application. © 2014 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

  8. Water and nonelectrolyte permeability of isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Alpini, G.; Garrick, R.A.; Jones, M.J.; Nunes, R.; Tavoloni, N.

    1986-01-01

    We have measured the diffusive permeability coefficients of isolated rat hepatocytes to 3 H 2 O, [ 14 C]urea, [ 14 C]erythritol, [ 14 C]mannitol, [ 3 H]sucrose, and [ 3 H]inulin, employing a technique previously developed for erythrocytes (Redwood et al., J. Gen. Physiol 64:706-729, 1974). Diffusion coefficients for the tracer molecules were measured in packed hepatocytes, supernatant fluid, and intracellular medium (lysed hepatocytes) and were calculated assuming one-dimensional semi-infinite diffusion through a homogeneous medium. By applying the series-parallel pathway model, the following permeability coefficients (10(-5) cm/sec) for the hepatocyte plasma membrane were obtained. 3 H 2 O, 98.6 +/- 18.4; [ 14 C]urea, 18.2 +/- 5.3; [ 14 C]erythritol, 4.8 +/- 1.6; [ 14 C]mannitol, 3.1 +/- 1.4; [ 3 H]sucrose, 0; [ 3 H]inulin, 0. These results indicate that isolated rat hepatocytes are highly permeable to water and polar nonelectrolytes, when compared with other transporting epithelia. This relatively high cellular permeability is consistent with a model in which nonelectrolyte permeation is via an aqueous pathway of equivalent pore diameter of 8-12 A. The finding that [ 14 C]erythritol and [ 14 C]mannitol cross the hepatocyte plasma membrane indicates that these molecules enter the bile canaliculus through the transcellular route. Conversely, the failure of [ 3 H]sucrose and [ 3 H]inulin to permeate the hepatocyte in the isolated condition supports the concept that biliary entry of these large carbohydrates, at least that fraction which cannot be accounted for by a vesicular mechanism, must occur via the transjunctional shunt pathway

  9. Microlaser-based displays

    Science.gov (United States)

    Bergstedt, Robert; Fink, Charles G.; Flint, Graham W.; Hargis, David E.; Peppler, Philipp W.

    1997-07-01

    Laser Power Corporation has developed a new type of projection display, based upon microlaser technology and a novel scan architecture, which provides the foundation for bright, extremely high resolution images. A review of projection technologies is presented along with the limitations of each and the difficulties they experience in trying to generate high resolution imagery. The design of the microlaser based projector is discussed along with the advantage of this technology. High power red, green, and blue microlasers have been designed and developed specifically for use in projection displays. These sources, in combination with high resolution, high contrast modulator, produce a 24 bit color gamut, capable of supporting the full range of real world colors. The new scan architecture, which reduces the modulation rate and scan speeds required, is described. This scan architecture, along with the inherent brightness of the laser provides the fundamentals necessary to produce a 5120 by 4096 resolution display. The brightness and color uniformity of the display is excellent, allowing for tiling of the displays with far fewer artifacts than those in a traditionally tiled display. Applications for the display include simulators, command and control centers, and electronic cinema.

  10. Destruction of the hepatocyte junction by intercellular invasion of Leptospira causes jaundice in a hamster model of Weil's disease.

    Science.gov (United States)

    Miyahara, Satoshi; Saito, Mitsumasa; Kanemaru, Takaaki; Villanueva, Sharon Y A M; Gloriani, Nina G; Yoshida, Shin-ichi

    2014-08-01

    Weil's disease, the most severe form of leptospirosis, is characterized by jaundice, haemorrhage and renal failure. The mechanisms of jaundice caused by pathogenic Leptospira remain unclear. We therefore aimed to elucidate the mechanisms by integrating histopathological changes with serum biochemical abnormalities during the development of jaundice in a hamster model of Weil's disease. In this work, we obtained three-dimensional images of infected hamster livers using scanning electron microscope together with freeze-cracking and cross-cutting methods for sample preparation. The images displayed the corkscrew-shaped bacteria, which infiltrated the Disse's space, migrated between hepatocytes, detached the intercellular junctions and disrupted the bile canaliculi. Destruction of bile canaliculi coincided with the elevation of conjugated bilirubin, aspartate transaminase and alkaline phosphatase levels in serum, whereas serum alanine transaminase and γ-glutamyl transpeptidase levels increased slightly, but not significantly. We also found in ex vivo experiments that pathogenic, but not non-pathogenic leptospires, tend to adhere to the perijunctional region of hepatocyte couplets isolated from hamsters and initiate invasion of the intercellular junction within 1 h after co-incubation. Our results suggest that pathogenic leptospires invade the intercellular junctions of host hepatocytes, and this invasion contributes in the disruption of the junction. Subsequently, bile leaks from bile canaliculi and jaundice occurs immediately. Our findings revealed not only a novel pathogenicity of leptospires, but also a novel mechanism of jaundice induced by bacterial infection. © 2014 The Authors. International Journal of Experimental Pathology © 2014 International Journal of Experimental Pathology.

  11. In vitro culture of functionally active buffalo hepatocytes isolated by using a simplified manual perfusion method.

    Directory of Open Access Journals (Sweden)

    Santanu Panda

    Full Text Available In farm animals, there is no suitable cell line available to understand liver-specific functions. This has limited our understanding of liver function and metabolism in farm animals. Culturing and maintenance of functionally active hepatocytes is difficult, since they survive no more than few days. Establishing primary culture of hepatocytes can help in studying cellular metabolism, drug toxicity, hepatocyte specific gene function and regulation. Here we provide a simple in vitro method for isolation and short-term culture of functionally active buffalo hepatocytes.Buffalo hepatocytes were isolated from caudate lobes by using manual enzymatic perfusion and mechanical disruption of liver tissue. Hepatocyte yield was (5.3 ± 0.66×107 cells per gram of liver tissue with a viability of 82.3 ± 3.5%. Freshly isolated hepatocytes were spherical with well contrasted border. After 24 hours of seeding onto fibroblast feeder layer and different extracellular matrices like dry collagen, matrigel and sandwich collagen coated plates, hepatocytes formed confluent monolayer with frequent clusters. Cultured hepatocytes exhibited typical cuboidal and polygonal shape with restored cellular polarity. Cells expressed hepatocyte-specific marker genes or proteins like albumin, hepatocyte nuclear factor 4α, glucose-6-phosphatase, tyrosine aminotransferase, cytochromes, cytokeratin and α1-antitrypsin. Hepatocytes could be immunostained with anti-cytokeratins, anti-albumin and anti α1-antitrypsin antibodies. Abundant lipid droplets were detected in the cytosol of hepatocytes using oil red stain. In vitro cultured hepatocytes could be grown for five days and maintained for up to nine days on buffalo skin fibroblast feeder layer. Cultured hepatocytes were viable for functional studies.We developed a convenient and cost effective technique for hepatocytes isolation for short-term culture that exhibited morphological and functional characteristics of active hepatocytes

  12. Whole-body γ-irradiation decelerates rat hepatocyte polyploidization.

    Science.gov (United States)

    Ikhtiar, Adnan M

    2015-07-01

    To characterize hepatocyte polyploidization induced by intermediate dose of γ-ray. Male Wistar strain rats were whole-body irradiated (WBI) with 2 Gy of γ-ray at the age of 1 month, and 5-6 rats were sacrificed monthly at 0-25 months after irradiation. The nuclear DNA content of individual hepatocytes was measured by flow cytometry, then hepatocytes were classified into various ploidy classes. Survival percentage, after exposure up to the end of the study, did not indicate any differences between the irradiated groups and controls. The degree of polyploidization in hepatocytes of irradiated rats, was significantly lower than that for the control after 1 month of exposure, and it continued to be lower after up to 8 months. Thereafter, the degree of polyploidization in the irradiated group slowly returned to the control level when the irradiated rats reached the age of 10 months. Intermediate dose of ionizing radiation, in contrast to high doses, decelerate hepatocyte polyploidization, which may coincides with the hypothesis of the beneficial effects of low doses of ionizing radiation.

  13. ENERGY STAR Certified Displays

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 7.0 ENERGY STAR Program Requirements for Displays that are effective as of July 1, 2016....

  14. Improvements in data display

    International Nuclear Information System (INIS)

    Ellis, G.W.

    1979-01-01

    An analog signal processor is described in this patent for connecting a source of analog signals to a cathode ray tube display in order to extend the dynamic range of the display. This has important applications in the field of computerised X-ray tomography since significant medical information, such as tumours in soft tissue, is often represented by minimal level changes in image density. Cathode ray tube displays are limited to approximately 15 intensity levels. Thus if both strong and weak absorption of the X-rays occurs, the dynamic range of the transmitted signals will be too large to permit small variations to be examined directly on a cathode ray display. Present tomographic image reconstruction methods are capable of quantising X-ray absorption density measurements into 256 or more distinct levels and a description is given of the electronics which enables the upper and lower range of intensity levels to be independently set and continuously varied. (UK)

  15. Gamma camera display system

    International Nuclear Information System (INIS)

    Stout, K.J.

    1976-01-01

    A gamma camera having an array of photomultipliers coupled via pulse shaping circuitry and a resistor weighting circuit to a display for forming an image of a radioactive subject is described. A linearizing circuit is coupled to the weighting circuit, the linearizing circuit including a nonlinear feedback circuit with diode coupling to the weighting circuit for linearizing the correspondence between points of the display and points of the subject. 4 Claims, 5 Drawing Figures

  16. Flexible displays, rigid designs?

    DEFF Research Database (Denmark)

    Hornbæk, Kasper

    2015-01-01

    Rapid technological progress has enabled a wide range of flexible displays for computing devices, but the user experience--which we're only beginning to understand--will be the key driver for successful designs.......Rapid technological progress has enabled a wide range of flexible displays for computing devices, but the user experience--which we're only beginning to understand--will be the key driver for successful designs....

  17. A refined characterisation of the NeoHepatocyte phenotype necessitates a reappraisal of the transdifferentiation hypothesis.

    Science.gov (United States)

    Riquelme, Paloma; Wundt, Judith; Hutchinson, James A; Brulport, Marc; Jun, Yu; Sotnikova, Anna; Girreser, Ulrich; Braun, Felix; Gövert, Felix; Soria, Bernat; Nüssler, Andreas; Clement, Bernd; Hengstler, Jan G; Fändrich, Fred

    2009-03-01

    Under certain culture conditions human peripheral blood monocytes may be induced to express phenotypic markers of non-haematopoietic lineages, including hepatocyte-defining traits. One such example, the NeoHepatocyte, was previously shown to express a broad panel of hepatocyte-like marker antigens and metabolic activities, both in vitro and following engraftment in the liver of immunodeficient mice. In this report, a refined description of NeoHepatocytes, with regard to their expression of xenobiotic-metabolising enzymes, morphology, hepatocyte marker expression and cell surface phenotype, is presented in comparison with human macrophages in defined states of activation. Contrary to prior assertions, it would seem more likely that NeoHepatocytes express particular hepatocyte-defining genes during a normal programme of macrophage differentiation rather than undergoing a process of transdifferentiation to become hepatocyte-like cells.

  18. Determination of metabolic stability using cryopreserved hepatocytes from rainbow trout (Oncorhynchus mykiss)

    Science.gov (United States)

    Standard protocols for isolating, cryopreserving, and thawing rainbow trout hepatocytes are described, along with procedures for using fresh or cryopreserved hepatocytes to assess chemical metabolic stability in fish by means of a substrate depletion approach. Variations on thes...

  19. Alternative Cell Sources to Adult Hepatocytes for Hepatic Cell Therapy.

    Science.gov (United States)

    Pareja, Eugenia; Gómez-Lechón, María José; Tolosa, Laia

    2017-01-01

    Adult hepatocyte transplantation is limited by scarce availability of suitable donor liver tissue for hepatocyte isolation. New cell-based therapies are being developed to supplement whole-organ liver transplantation, to reduce the waiting-list mortality rate, and to obtain more sustained and significant metabolic correction. Fetal livers and unsuitable neonatal livers for organ transplantation have been proposed as potential useful sources of hepatic cells for cell therapy. However, the major challenge is to use alternative cell sources for transplantation that can be derived from reproducible methods. Different types of stem cells with hepatic differentiation potential are eligible for generating large numbers of functional hepatocytes for liver cell therapy to treat degenerative disorders, inborn hepatic metabolic diseases, and organ failure. Clinical trials are designed to fully establish the safety profile of such therapies and to define target patient groups and standardized protocols.

  20. Receptor-mediated uptake of low density lipoprotein stimulates bile acid synthesis by cultured rat hepatocytes

    International Nuclear Information System (INIS)

    Junker, L.H.; Davis, R.A.

    1989-01-01

    The cellular mechanisms responsible for the lipoprotein-mediated stimulation of bile acid synthesis in cultured rat hepatocytes were investigated. Adding 280 micrograms/ml of cholesterol in the form of human or rat low density lipoprotein (LDL) to the culture medium increased bile acid synthesis by 1.8- and 1.6-fold, respectively. As a result of the uptake of LDL, the synthesis of [14C]cholesterol from [2-14C]acetate was decreased and cellular cholesteryl ester mass was increased. Further studies demonstrated that rat apoE-free LDL and apoE-rich high density lipoprotein (HDL) both stimulated bile acid synthesis 1.5-fold, as well as inhibited the formation of [14C]cholesterol from [2-14C]acetate. Reductive methylation of LDL blocked the inhibition of cholesterol synthesis, as well as the stimulation of bile acid synthesis, suggesting that these processes require receptor-mediated uptake. To identify the receptors responsible, competitive binding studies using 125I-labeled apoE-free LDL and 125I-labeled apoE-rich HDL were performed. Both apoE-free LDL and apoE-rich HDL displayed an equal ability to compete for binding of the other, suggesting that a receptor or a group of receptors that recognizes both apolipoproteins is involved. Additional studies show that hepatocytes from cholestyramine-treated rats displayed 2.2- and 3.4-fold increases in the binding of apoE-free LDL and apoE-rich HDL, respectively. These data show for the first time that receptor-mediated uptake of LDL by the liver is intimately linked to processes activating bile acid synthesis

  1. Property of hepatitis B virus replication in Tupaia belangeri hepatocytes.

    Science.gov (United States)

    Sanada, Takahiro; Tsukiyama-Kohara, Kyoko; Yamamoto, Naoki; Ezzikouri, Sayeh; Benjelloun, Soumaya; Murakami, Shuko; Tanaka, Yasuhito; Tateno, Chise; Kohara, Michinori

    2016-01-08

    The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3-6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10(5) copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10(4)-10(6) copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10(3) copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Information rich display design

    International Nuclear Information System (INIS)

    Welch, Robin; Braseth, Alf Ove; Veland, Oeystein

    2004-01-01

    This paper presents the concept Information Rich Displays. The purpose of Information Rich Displays (IRDs) is to condensate prevailing information in process displays in such a way that each display format (picture) contains more relevant information for the user. Compared to traditional process control displays, this new concept allows the operator to attain key information at a glance and at the same time allows for improved monitoring of larger portions of the process. This again allows for reduced navigation between both process and trend displays and ease the cognitive demand on the operator. This concept has been created while working on designing display prototypes for the offshore petroleum production facilities of tomorrow. Offshore installations basically consist of wells, separation trains (where oil, gas and water are separated from each other), an oil tax measurement system (where oil quality is measured and the pressure increased to allow for export), gas compression (compression of gas for export) and utility systems (water treatment, chemical systems etc.). This means that an offshore control room operator has to deal with a complex process that comprises several functionally different systems. The need for a new approach to offshore display format design is in particular based on shortcomings in today's designs related to the keyhole effect, where the display format only reveals a fraction of the whole process. Furthermore, the upcoming introduction of larger off- and on-shore operation centres will increase the size and complexity of the operators' work domain. In the light of the increased demands on the operator, the proposed IRDs aim to counter the negative effects this may have on the workload. In this work we have attempted to classify the wide range of different roles an operator can have in different situations. The information content and amount being presented to the operator in a display should be viewed in context of the roles the

  3. Interspecies differences in metabolism of arsenic by cultured primary hepatocytes

    International Nuclear Information System (INIS)

    Drobna, Zuzana; Walton, Felecia S.; Harmon, Anne W.; Thomas, David J.; Styblo, Miroslav

    2010-01-01

    Biomethylation is the major pathway for the metabolism of inorganic arsenic (iAs) in many mammalian species, including the human. However, significant interspecies differences have been reported in the rate of in vivo metabolism of iAs and in yields of iAs metabolites found in urine. Liver is considered the primary site for the methylation of iAs and arsenic (+3 oxidation state) methyltransferase (As3mt) is the key enzyme in this pathway. Thus, the As3mt-catalyzed methylation of iAs in the liver determines in part the rate and the pattern of iAs metabolism in various species. We examined kinetics and concentration-response patterns for iAs methylation by cultured primary hepatocytes derived from human, rat, mice, dog, rabbit, and rhesus monkey. Hepatocytes were exposed to [ 73 As]arsenite (iAs III ; 0.3, 0.9, 3.0, 9.0 or 30 nmol As/mg protein) for 24 h and radiolabeled metabolites were analyzed in cells and culture media. Hepatocytes from all six species methylated iAs III to methylarsenic (MAs) and dimethylarsenic (DMAs). Notably, dog, rat and monkey hepatocytes were considerably more efficient methylators of iAs III than mouse, rabbit or human hepatocytes. The low efficiency of mouse, rabbit and human hepatocytes to methylate iAs III was associated with inhibition of DMAs production by moderate concentrations of iAs III and with retention of iAs and MAs in cells. No significant correlations were found between the rate of iAs methylation and the thioredoxin reductase activity or glutathione concentration, two factors that modulate the activity of recombinant As3mt. No associations between the rates of iAs methylation and As3mt protein structures were found for the six species examined. Immunoblot analyses indicate that the superior arsenic methylation capacities of dog, rat and monkey hepatocytes examined in this study may be associated with a higher As3mt expression. However, factors other than As3mt expression may also contribute to the interspecies differences

  4. Microencapsulation of Hepatocytes and Mesenchymal Stem Cells for Therapeutic Applications.

    Science.gov (United States)

    Meier, Raphael P H; Montanari, Elisa; Morel, Philippe; Pimenta, Joël; Schuurman, Henk-Jan; Wandrey, Christine; Gerber-Lemaire, Sandrine; Mahou, Redouan; Bühler, Leo H

    2017-01-01

    Encapsulated hepatocyte transplantation and encapsulated mesenchymal stem cell transplantation are newly developed potential treatments for acute and chronic liver diseases, respectively. Cells are microencapsulated in biocompatible semipermeable alginate-based hydrogels. Microspheres protect cells against antibodies and immune cells, while allowing nutrients, small/medium size proteins and drugs to diffuse inside and outside the polymer matrix. Microencapsulated cells are assessed in vitro and designed for experimental transplantation and for future clinical applications.Here, we describe the protocol for microencapsulation of hepatocytes and mesenchymal stem cells within hybrid poly(ethylene glycol)-alginate hydrogels.

  5. No evidence for protective erythropoietin alpha signalling in rat hepatocytes

    Directory of Open Access Journals (Sweden)

    Frede Stilla

    2009-04-01

    Full Text Available Abstract Background Recombinant human erythropoietin alpha (rHu-EPO has been reported to protect the liver of rats and mice from ischemia-reperfusion injury. However, direct protective effects of rHu-EPO on hepatocytes and the responsible signalling pathways have not yet been described. The aim of the present work was to study the protective effect of rHu-EPO on warm hypoxia-reoxygenation and cold-induced injury to hepatocytes and the rHu-EPO-dependent signalling involved. Methods Loss of viability of isolated rat hepatocytes subjected to hypoxia/reoxygenation or incubated at 4°C followed by rewarming was determined from released lactate dehydrogenase activity in the absence and presence of rHu-EPO (0.2–100 U/ml. Apoptotic nuclear morphology was assessed by fluorescence microscopy using the nuclear fluorophores H33342 and propidium iodide. Erythropoietin receptor (EPOR, EPO and Bcl-2 mRNAs were quantified by real time PCR. Activation of JAK-2, STAT-3 and STAT-5 in hepatocytes and rat livers perfused in situ was assessed by Western blotting. Results In contrast to previous in vivo studies on ischemia-reperfusion injury to the liver, rHu-EPO was without any protective effect on hypoxic injury, hypoxia-reoxygenation injury and cold-induced apoptosis to isolated cultured rat hepatocytes. EPOR mRNA was identified in these cells but specific detection of the EPO receptor protein was not possible due to the lack of antibody specificity. Both, in the cultured rat hepatocytes (10 U/ml for 15 minutes and in the rat liver perfused in situ with rHu-EPO (8.9 U/ml for 15 minutes no evidence for EPO-dependent signalling was found as indicated by missing effects of rHu-EPO on phosphorylation of JAK-2, STAT-3 and STAT-5 and on the induction of Bcl-2 mRNA. Conclusion Together, these results indicate the absence of any protective EPO signalling in rat hepatocytes. This implies that the protection provided by rHu-EPO in vivo against ischemia-reperfusion and

  6. Dichroic Liquid Crystal Displays

    Science.gov (United States)

    Bahadur, Birendra

    The following sections are included: * INTRODUCTION * DICHROIC DYES * Chemical Structure * Chemical and Photochemical Stability * THEORETICAL MODELLING * DEFECTS CAUSED BY PROLONGED LIGHT IRRADIATION * CHEMICAL STRUCTURE AND PHOTOSTABILITY * OTHER PARAMETERS AFFECTING PHOTOSTABILITY * CELL PREPARATION * DICHROIC PARAMETERS AND THEIR MEASUREMENTS * Order Parameter and Dichroic Ratio Of Dyes * Absorbance, Order Parameter and Dichroic Ratio Measurements * IMPACT OF DYE STRUCTURE AND LIQUID CRYSTAL HOST ON PHYSICAL PROPERTIES OF A DICHROIC MIXTURE * Order Parameter and Dichroic Ratio * EFFECT OF LENGTH OF DICHROIC DYES ON THE ORDER PARAMETER * EFFECT OF THE BREADTH OF DYE ON THE ORDER PARAMETER * EFFECT OF THE HOST ON THE ORDER PARAMETER * TEMPERATURE VARIATION OF THE ORDER PARAMETER OF DYES IN A LIQUID CRYSTAL HOST * IMPACT OF DYE CONCENTRATION ON THE ORDER PARAMETER * Temperature Range * Viscosity * Dielectric Constant and Anisotropy * Refractive Indices and Birefringence * solubility43,153-156 * Absorption Wavelength and Auxochromic Groups * Molecular Engineering of Dichroic Dyes * OPTICAL, ELECTRO-OPTICAL AND LIFE PARAMETERS * Colour And CIE Colour space120,160-166 * CIE 1931 COLOUR SPACE * CIE 1976 CHROMATICITY DIAGRAM * CIE UNIFORM COLOUR SPACES & COLOUR DIFFERENCE FORMULAE120,160-166 * Electro-Optical Parameters120 * LUMINANCE * CONTRAST AND CONTRAST RATIO * SWITCHING SPEED * Life Parameters and Failure Modes * DICHROIC MIXTURE FORMULATION * Monochrome Mixture * Black Mixture * ACHROMATIC BLACK MIXTURE FOR HEILMEIER DISPLAYS * Effect of Illuminant on Display Colour * Colour of the Field-On State * Effect of Dye Linewidth * Optimum Centroid Wavelengths * Effect of Dye Concentration * Mixture Formulation Using More Than Three Dyes * ACHROMATIC MIXTURE FOR WHITE-TAYLOR TYPE DISPLAYS * HEILMEIER DISPLAYS * Theoretical Modelling * Threshold Characteristic * Effects of Dye Concentration on Electro-optical Parameters * Effect of Cholesteric Doping * Effect of Alignment

  7. On Integrity of Flexible Displays

    Science.gov (United States)

    Bouten, Piet C. P.

    Nowadays two display types are dominant in the display market: the bulky cathode ray tube (CRT) and liquid crystal displays (LCD). Both types use glass as substrate material. The LCD display is the dominant player for mobile applications, in for instance mobile phones and portable computers. In the development of displays and their applications a clear interest exists to replace the rigid rectangular display cells by free-shaped, curved or even roll-up cells. These types of applications require flexible displays.

  8. Inducibility of carbamoylphosphate synthetase (ammonia) in cultures of embryonic hepatocytes: ontogenesis of the responsiveness to hormones

    NARCIS (Netherlands)

    Lamers, W. H.; Zonneveld, D.; Charles, R.

    1984-01-01

    Glucocorticosteroids and cyclic AMP induce carbamoylphosphate synthetase (ammonia) (CPS) in rat hepatocytes. Using an enzyme immunoassay applied to hepatocyte cultures fixed in situ, it has been demonstrated that the capacity of hepatocytes to synthesize CPS in the presence of both hormones is

  9. Billion-scale production of hepatocyte-like cells from human induced pluripotent stem cells.

    Science.gov (United States)

    Yamashita, Tomoki; Takayama, Kazuo; Sakurai, Fuminori; Mizuguchi, Hiroyuki

    2018-02-19

    Human induced pluripotent stem (iPS) cell-derived hepatocyte-like cells are expected to be utilized in drug screening and regenerative medicine. However, hepatocyte-like cells have not been fully used in such applications because it is difficult to produce such cells on a large scale. In this study, we tried to establish a method to mass produce hepatocyte-like cells using a three-dimensional (3D) cell culture bioreactor called the Rotary Cell Culture System (RCCS). RCCS enabled us to obtain homogenous hepatocyte-like cells on a billion scale (>10 9  cells). The gene expression levels of some hepatocyte markers (alpha-1 antitrypsin, cytochrome (CYP) 1A2, CYP2D6, and hepatocyte nuclear factor 4alpha) were higher in 3D-cultured hepatocyte-like cells than in 2D-cultured hepatocyte-like cells. This result suggests that RCCS could provide more suitable conditions for hepatocyte maturation than the conventional 2D cell culture conditions. In addition, more than 90% of hepatocyte-like cells were positive for albumin and could uptake low-density lipoprotein in the culture medium. We succeeded in the large-scale production of homogenous and functional hepatocyte-like cells from human iPS cells. This technology will be useful in drug screening and regenerative medicine, which require enormous numbers of hepatocyte-like cells. Copyright © 2018 Elsevier Inc. All rights reserved.

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  15. File list: Oth.Liv.50.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  16. File list: InP.Liv.10.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  17. File list: ALL.Liv.10.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  18. File list: ALL.Liv.50.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  19. File list: ALL.Liv.50.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  20. File list: Pol.Liv.10.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  1. File list: Oth.Liv.05.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  2. File list: Oth.Liv.20.AllAg.Hepatocytes [Chip-atlas[Archive

    Lifescience Database Archive (English)

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  3. Paediatric dose display

    International Nuclear Information System (INIS)

    Griffin, D.W.; Derges, S.; Hesslewood, S.

    1984-01-01

    A compact, inexpensive unit, based on an 8085 microprocessor, has been designed for calculating doses of intravenous radioactive injections for children. It has been used successfully for over a year. The dose is calculated from the body surface area and the result displayed in MBq. The operator can obtain the required dose on a twelve character alphanumeric display by entering the age of the patient and the adult dose using a hexadecimal keyboard. Circuit description, memory map and input/output, and firmware are dealt with. (U.K.)

  4. Radiation-induced PKC signaling system in cultured rat hepatocytes

    International Nuclear Information System (INIS)

    Nakajima, Tetsuo; Yukawa, Osami

    1998-01-01

    Radiation effects on living organisms are mainly caused through reactive oxygen species (ROS) on living cells. It is known that ROS damages various membranes and the bio membranes play an important role in cellular signal transduction pathways. The effects of radiation on cellular signal transduction pathways in cultured rat hepatocytes have been studied

  5. Insulin infusion reduces hepatocyte growth factor in lean humans

    DEFF Research Database (Denmark)

    de Courten, Barbora; de Courten, Maximilian; Dougherty, Sonia

    2013-01-01

    OBJECTIVE: Plasma Hepatocyte Growth Factor (HGF) is significantly elevated in obesity and may contribute to vascular disease, metabolic syndrome or cancer in obese individuals. The current studies were done to determine if hyperinsulinemia increases plasma HGF. MATERIALS/METHODS: Twenty-two parti...

  6. Aniline Induces Oxidative Stress and Apoptosis of Primary Cultured Hepatocytes

    Directory of Open Access Journals (Sweden)

    Yue Wang

    2016-11-01

    Full Text Available The toxicity and carcinogenicity of aniline in humans and animals have been well documented. However, the molecular mechanism involved in aniline-induced liver toxicity and carcinogenesis remains unclear. In our research, primary cultured hepatocytes were exposed to aniline (0, 1.25, 2.50, 5.0 and 10.0 μg/mL for 24 h in the presence or absence of N-acetyl-l-cysteine (NAC. Levels of reactive oxygen species (ROS, malondialdehyde (MDA, and glutathione (GSH, activities of superoxide dismutase (SOD and catalase (CAT, mitochondrial membrane potential, DNA damage, cell viability, and apoptosis were detected. Levels of ROS and MDA were significantly increased and levels of GSH and CAT, activity of SOD, and mitochondrial membrane potential in hepatocytes were significantly decreased by aniline compared with the negative control group. The tail moment and DNA content of the tail in exposed groups were significantly higher than those in the negative control group. Cell viability was reduced and apoptotic death was induced by aniline in a concentration-dependent manner. The phenomena of ROS generation, oxidative damage, loss of mitochondrial membrane potential, DNA damage and apoptosis could be prevented if ROS inhibitor NAC was added. ROS generation is involved in the loss of mitochondrial membrane potential and DNA injury, which may play a role in aniline-induced apoptosis in hepatocytes. Our study provides insight into the mechanism of aniline-induced toxicity and apoptosis of hepatocytes.

  7. The use of pig hepatocytes for biotransformation and toxicity studies

    NARCIS (Netherlands)

    Hoogenboom, L.A.P.

    1991-01-01

    The three main objectives of this study were, (1) to investigate the possibility to isolate viable hepatocytes from liver samples of pigs, (2) to study their use for biotransformation and toxicity studies, and (3) to demonstrate the value of this model, in particular in the field of residue

  8. Hepatocytes in the development of liver support systems

    NARCIS (Netherlands)

    I.H.M. Borel Rinkes (Inne)

    1993-01-01

    textabstractThis thesis focuses on the development of alternative strategies in the treatment of patients with acute fulminant hepatic failure and inborn errors of metabolism, using hepatocytes as the basis of liver support. When compared with transplantation of the liver as an organ, the

  9. Hepatocyte heterogeneity in the metabolism of amino acids and ammonia

    NARCIS (Netherlands)

    Häussinger, D.; Lamers, W. H.; Moorman, A. F.

    1992-01-01

    With respect to hepatocyte heterogeneity in ammonia and amino acid metabolism, two different patterns of sublobular gene expression are distinguished: 'gradient-type' and 'strict- or compartment-type' zonation. An example for strict-type zonation is the reciprocal distribution of carbamoylphosphate

  10. Refreshing Refreshable Braille Displays.

    Science.gov (United States)

    Russomanno, Alexander; O'Modhrain, Sile; Gillespie, R Brent; Rodger, Matthew W M

    2015-01-01

    The increased access to books afforded to blind people via e-publishing has given them long-sought independence for both recreational and educational reading. In most cases, blind readers access materials using speech output. For some content such as highly technical texts, music, and graphics, speech is not an appropriate access modality as it does not promote deep understanding. Therefore blind braille readers often prefer electronic braille displays. But, these are prohibitively expensive. The search is on, therefore, for a low-cost refreshable display that would go beyond current technologies and deliver graphical content as well as text. And many solutions have been proposed, some of which reduce costs by restricting the number of characters that can be displayed, even down to a single braille cell. In this paper, we demonstrate that restricting tactile cues during braille reading leads to poorer performance in a letter recognition task. In particular, we show that lack of sliding contact between the fingertip and the braille reading surface results in more errors and that the number of errors increases as a function of presentation speed. These findings suggest that single cell displays which do not incorporate sliding contact are likely to be less effective for braille reading.

  11. Small - Display Cartography

    DEFF Research Database (Denmark)

    Nissen, Flemming; Hvas, Anders; Münster-Swendsen, Jørgen

    Service Communication and finally, Part IV: Concluding remarks and topics for further research on small-display cartography. Part II includes a separate Appendix D consisting of a cartographic design specification. Part III includes a separate Appendix C consisting of a schema specification, a separate...

  12. Nuclear image display controller

    International Nuclear Information System (INIS)

    Roth, D.A.

    1985-01-01

    In a nuclear imaging system the digitized x and y coordinates of gamma ray photon emission events address memory locations corresponding to the coordinates. The respective locations are incremented each time they are addressed so at the end of a selected time or event count period the locations contain digital values or raw data corresponding to the intensity of pixels comprising an image frame. The raw data for a frame is coupled to one input of an arithmetic logic unit (ALU) whose output is coupled to a display controller memory. The output of the controller memory is coupled to another ALU input with a feedback bus and is also coupled to a further signal processing circuit which includes means for converting processed data to analog video signals for television display. The ALU is selectively controlled to let raw image data pass through to the display controllor memory or alternately to add (or subtract) raw data for the last image frame developed to the raw data for preceding frames held in the display controller to thereby produce the visual effect on the television screen of an isotope flowing through anatomy

  13. Plant state display device

    International Nuclear Information System (INIS)

    Kadota, Kazuo; Ito, Toshiichiro.

    1994-01-01

    The device of the present invention conducts information processing suitable for a man to solve a problem in a plant such as a nuclear power plant incorporating a great amount of information, where safety is required and provides information to an operator. Namely, theories and rules with respect to the flow and balanced state of materials and energy upon plant start-up, and a vapor cycle of operation fluids are symbolized and displayed on the display screen of the device. Then, the display of the plant information suitable to the information processing for a man to dissolve problems is provided. Accordingly, a mechanism for analyzing a purpose of the plant is made more definite, thereby enabling to prevent an erroneous judgement of an operator and occurrence of plant troubles. In addition, a simular effect can also be expected when the theories and rules with respect to the flow and the balanced state of materials and energy and thermohydrodynamic behavior of the operation fluids in a state of after-heat removing operation during shutdown of the plant are symbolized and displayed. (I.S.)

  14. Induction of hepatocyte polyploidization in rats of different age by ionizing radiation of different LET

    International Nuclear Information System (INIS)

    Gil'yano, N.Ya.; Malinovskij, O.V.; Khair, M.B.

    1992-01-01

    A decrease in the effectiveness of neutron-irradiation with respect to fusion of nonproliferating hepatocytes of animals with age was shown by the method of flow cytometry. There was an inverse relationship between the effectiveness of induction of non-proliferating hepatocytes fusion and neutron energy. The process of hepatocyte fusion induced by neutrons was inhibited by uranyl acetate. No age-dependent changes were noted in the induction of polyploidization of proliferating hepatocytes by sparsely ionizing radiation. A hypothesis is proposed concerning a membrane nature of the target responsible for hepatocyte polyploidization induced by densely ionizing radiation. (authors). 8 refs., 4 figs., 5 tabs

  15. Induction of hepatocyte polyploidization in rats of different age by ionizing radiation of different LET

    International Nuclear Information System (INIS)

    Gil'yano, N.Ya.; Malinovskij, O.V.; Khair, M.B.

    1990-01-01

    A decrease in the effectiveness of neutron-irradiation with respect to fusion of nonproliferating hepatocytes of animals with age was shown by the method of flow cytometry. There was an inverse relationship between the effectiveness of induction of non-proliferating hepatocytes fusion and neutron energy. The process of hepatocyte fusion induced by neutrons was inhibited by uranyl acetate. No age-dependent changes were noted in the induction of polyploidization of proliferating hepatocytes by sparsely ionizing radiation. A hypothesis is proposed concerning a membrane nature of the target responsible for hepatocyte polyploidization induced by densely ionizing radiation

  16. Augmenter of liver regeneration (ALR) protects human hepatocytes against apoptosis

    International Nuclear Information System (INIS)

    Ilowski, Maren; Kleespies, Axel; Toni, Enrico N. de; Donabauer, Barbara; Jauch, Karl-Walter; Hengstler, Jan G.; Thasler, Wolfgang E.

    2011-01-01

    Research highlights: → ALR decreases cytochrome c release from mitochondria. → ALR protects hepatocytes against apoptosis induction by ethanol, TRAIL, anti-Apo, TGF-β and actinomycin D. → ALR exerts a liver-specific anti-apoptotic effect. → A possible medical usage of ALR regarding protection of liver cells during apoptosis inducing therapies. -- Abstract: Augmenter of liver regeneration (ALR) is known to support liver regeneration and to stimulate proliferation of hepatocytes. However, it is not known if ALR exerts anti-apoptotic effects in human hepatocytes and whether this protective effect is cell type specific. This is relevant, because compounds that protect the liver against apoptosis without undesired effects, such as protection of metastatic tumour cells, would be appreciated in several clinical settings. Primary human hepatocytes (phH) and organotypic cancer cell lines were exposed to different concentrations of apoptosis inducers (ethanol, TRAIL, anti-Apo, TGF-β, actinomycin D) and cultured with or without recombinant human ALR (rhALR). Apoptosis was evaluated by the release of cytochrome c from mitochondria and by FACS with propidium iodide (PI) staining. ALR significantly decreased apoptosis induced by ethanol, TRAIL, anti-Apo, TGF-β and actinomycin D. Further, the anti-apoptotic effect of ALR was observed in primary human hepatocytes and in HepG2 cells but not in bronchial (BC1), colonic (SW480), gastric (GC1) and pancreatic (L3.6PL) cell lines. Therefore, the hepatotrophic growth factor ALR acts in a liver specific manner with regards to both its mitogenic and its anti-apoptotic effect. Unlike the growth factors HGF and EGF, rhALR acts in a liver specific manner. Therefore, ALR is a promising candidate for further evaluation as a possible hepatoprotective factor in clinical settings.

  17. Augmenter of liver regeneration (ALR) protects human hepatocytes against apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Ilowski, Maren [Liver Regeneration Group, Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Kleespies, Axel [Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Toni, Enrico N. de [Department of Medicine II, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Donabauer, Barbara [Liver Regeneration Group, Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Jauch, Karl-Walter [Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Hengstler, Jan G. [Leibniz Research Centre for Working Environment and Human Factors, Technical University, Dortmund (Germany); Thasler, Wolfgang E., E-mail: wolfgang.thasler@med.uni-muenchen.de [Liver Regeneration Group, Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany); Department of Surgery, Grosshadern Hospital, Ludwig Maximilians University, Munich (Germany)

    2011-01-07

    Research highlights: {yields} ALR decreases cytochrome c release from mitochondria. {yields} ALR protects hepatocytes against apoptosis induction by ethanol, TRAIL, anti-Apo, TGF-{beta} and actinomycin D. {yields} ALR exerts a liver-specific anti-apoptotic effect. {yields} A possible medical usage of ALR regarding protection of liver cells during apoptosis inducing therapies. -- Abstract: Augmenter of liver regeneration (ALR) is known to support liver regeneration and to stimulate proliferation of hepatocytes. However, it is not known if ALR exerts anti-apoptotic effects in human hepatocytes and whether this protective effect is cell type specific. This is relevant, because compounds that protect the liver against apoptosis without undesired effects, such as protection of metastatic tumour cells, would be appreciated in several clinical settings. Primary human hepatocytes (phH) and organotypic cancer cell lines were exposed to different concentrations of apoptosis inducers (ethanol, TRAIL, anti-Apo, TGF-{beta}, actinomycin D) and cultured with or without recombinant human ALR (rhALR). Apoptosis was evaluated by the release of cytochrome c from mitochondria and by FACS with propidium iodide (PI) staining. ALR significantly decreased apoptosis induced by ethanol, TRAIL, anti-Apo, TGF-{beta} and actinomycin D. Further, the anti-apoptotic effect of ALR was observed in primary human hepatocytes and in HepG2 cells but not in bronchial (BC1), colonic (SW480), gastric (GC1) and pancreatic (L3.6PL) cell lines. Therefore, the hepatotrophic growth factor ALR acts in a liver specific manner with regards to both its mitogenic and its anti-apoptotic effect. Unlike the growth factors HGF and EGF, rhALR acts in a liver specific manner. Therefore, ALR is a promising candidate for further evaluation as a possible hepatoprotective factor in clinical settings.

  18. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes.

    Science.gov (United States)

    Hultman, Maria T; Song, You; Tollefsen, Knut Erik

    2015-12-01

    The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration-response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and revealed modulation of additional genes associated with apoptosis and cholesterol biosynthesis. Differentially expressed genes (DEGs) related to impaired lipid metabolism (e.g. peroxisome proliferator-activated receptor α and γ), growth (e.g. insulin growth factor protein 1), phase I and II biotransformation (e.g. cytochrome P450 1A, sulfotransferase, UDP-glucuronosyltransferase and glutathione S-transferase) provided additional

  19. Gender differences in methionine accumulation and metabolism in freshly isolated mouse hepatocytes: Potential roles in toxicity

    International Nuclear Information System (INIS)

    Dever, Joseph T.; Elfarra, Adnan A.

    2009-01-01

    L-Methionine (Met) is hepatotoxic at high concentrations. Because Met toxicity in freshly isolated mouse hepatocytes is gender-dependent, the goal of this study was to assess the roles of Met accumulation and metabolism in the increased sensitivity of male hepatocytes to Met toxicity compared with female hepatocytes. Male hepatocytes incubated with Met (30 mM) at 37 o C exhibited higher levels of intracellular Met at 0.5, 1.0, and 1.5 h, respectively, compared to female hepatocytes. Conversely, female hepatocytes had higher levels of S-adenosyl-L-methionine compared to male hepatocytes. Female hepatocytes also exhibited higher L-methionine-L-sulfoxide levels relative to control hepatocytes, whereas the increases in L-methionine-D-sulfoxide (Met-D-O) levels were similar in hepatocytes of both genders. Addition of aminooxyacetic acid (AOAA), an inhibitor of Met transamination, significantly increased Met levels at 1.5 h and increased Met-D-O levels at 1.0 and 1.5 h only in Met-exposed male hepatocytes. No gender differences in cytosolic Met transamination activity by glutamine transaminase K were detected. However, female mouse liver cytosol exhibited higher methionine-DL-sulfoxide (MetO) reductase activity than male mouse liver cytosol at low (0.25 and 0.5 mM) MetO concentrations. Collectively, these results suggest that increased cellular Met accumulation, decreased Met transmethylation, and increased Met and MetO transamination in male mouse hepatocytes may be contributing to the higher sensitivity of the male mouse hepatocytes to Met toxicity in comparison with female mouse hepatocytes.

  20. Position display device

    International Nuclear Information System (INIS)

    Nishizawa, Yukio.

    1974-01-01

    Object: To provide a device capable of easily and quickly reading mutual mounting relations of control bodies such as control rods mounted on a nuclear reactor and positions to which the control bodies are driven. Structure: A scanning circuit is provided to scan positions of controllably mounted control bodies such as control rods. Values detected by scanning the positions are converted into character signals according to the values and converted into preranked color signals. The character signals and color signals are stored in a memory circuit by synchronous signals in synchronism with the scanning in the scanning circuit. Outputs of the memory circuit are displayed by a display unit such as a color Braun tube in accordance with the synchronous signals to provide color representations according to positions to which control bodies are driven in the same positional relation as the mounting of the control bodies. (Kamimura, M.)

  1. Multichannel waveform display system

    International Nuclear Information System (INIS)

    Kolvankar, V.G.

    1989-01-01

    For any multichannel data acquisition system, a multichannel paper chart recorder undoubtedly forms an essential part of the system. When deployed on-line, it instantaneously provides, for visual inspection, hard copies of the signal waveforms on common time base at any desired sensitivity and time resolution. Within the country, only a small range of these strip chart recorder s is available, and under stringent specifications imported recorders are often procured. The cost of such recorders may range from 1 to 5 lakhs of rupees in foreign exchange. A system to provide on the oscilloscope a steady display of multichannel waveforms, refreshed from the digital data stored in the memory is developed. The merits and demerits of the display system are compared with that built around a conventional paper chart recorder. Various illustrations of multichannel seismic event data acquired at Gauribidanur seismic array station are also presented. (author). 2 figs

  2. Refrigerated display cabinets; Butikskyla

    Energy Technology Data Exchange (ETDEWEB)

    Fahlen, Per

    2000-07-01

    This report summarizes experience from SP research and assignments regarding refrigerated transport and storage of food, mainly in the retail sector. It presents the fundamentals of heat and mass transfer in display cabinets with special focus on indirect systems and secondary refrigerants. Moreover, the report includes a brief account of basic food hygiene and the related regulations. The material has been compiled for educational purposes in the Masters program at Chalmers Technical University.

  3. Helicopter Display Improvement Study

    Science.gov (United States)

    1975-05-01

    PRESSURE INDICATOR 43 TURN A N D SLIP INDICATOR 21 ENGINE AND SDG OIL IN TEMPERATURE INDICATOR 44 COURSE INDICATOR 22 RADIO MAGNETIC COMPASS INDICATOR... compass seemed to present a problem to several H-l series pilots In that It was poorly located and should be moved. Possible locations Included...the UH-lNs standby compass . Both H/L and L/L pilots agreed that internal, white light was the best system currently in use. INDIVIDUAL DISPLAYS

  4. Dyes for displays

    Science.gov (United States)

    Claussen, U.

    1984-01-01

    The improvement of contrast and visibility of LCD by two different means was undertaken. The two methods are: (1) development of fluorescent dyes to increase the visibility of fluorescent activated displays (FLAD); and (2) development of dichroic dyes to increase the contrast of displays. This work was done in close cooperation with the electronic industry, where the newly synthesized dyes were tested. The targets for the chemical synthesis were selected with the help of computer model calculations. A marketable range of dyes was developed. Since the interest of the electronic industries concerning FLAD was low, the investigations were stopped. Dichroic dyes, especially black mixtures with good light fastness, order parameter, and solubility in nematic phases were developed. The application of these dyes is restricted to indoor use because of an increase of viscosity below -10 C. Applications on a technical scale, e.g., for the automotive industry, will be possible if the displays work at temperatures down to -40 C. This problem requires a complex optimization of the dye/nematic phase system.

  5. Handbook of Visual Display Technology

    CERN Document Server

    Cranton, Wayne; Fihn, Mark

    2012-01-01

    The Handbook of Visual Display Technology is a unique work offering a comprehensive description of the science, technology, economic and human interface factors associated with the displays industry. An invaluable compilation of information, the Handbook will serve as a single reference source with expert contributions from over 150 international display professionals and academic researchers. All classes of display device are covered including LCDs, reflective displays, flexible solutions and emissive devices such as OLEDs and plasma displays, with discussion of established principles, emergent technologies, and particular areas of application. The wide-ranging content also encompasses the fundamental science of light and vision, image manipulation, core materials and processing techniques, display driving and metrology.

  6. Book Display as Adult Service

    Directory of Open Access Journals (Sweden)

    Matthew S. Moore

    1997-03-01

    Full Text Available 無Book display as an adult service is defined as choosing and positioning adult books from the collection to increase their circulation. The author contrasts bookstore arrangement for sales versus library arrangement for access. The paper considers the library-as-a-whole as a display, examines the right size for an in-library display, and discusses mass displays, end-caps, on-shelf displays, and the Tiffany approach. The author proposes that an effective display depends on an imaginative, unifying theme, and that book displays are part of the joy of libraries.

  7. NCAP projection displays

    Science.gov (United States)

    Havens, John R.; Ishioka, J.; Jones, Philip J.; Lau, Aldrich; Tomita, Akira; Asano, A.; Konuma, Nobuhiro; Sato, Kazuhiko; Takemoto, Iwao

    1997-05-01

    Projectors based on polymer-eNCAPsulated liquid crystals can provide bright displays suitable for use in conference rooms with normal lighting. Contrast is generated by light scattering among the droplets, rather than by light absorption with crossed polarizers. We have demonstrated a full-color, compact projector showing 1200 ANSI lumens with 200 watts of lamp power - a light efficiency of 6 lumens/watt. This projector is based on low-voltage NCAP material, highly reflective CMOS die, and matched illumination and projection optics. We will review each of these areas and discuss the integrated system performance.

  8. The cytoskeleton of digitonin-treated rat hepatocytes.

    Science.gov (United States)

    Fiskum, G; Craig, S W; Decker, G L; Lehninger, A L

    1980-06-01

    Treatment of isolated rat hepatocptes with low concentrations of digitonin increases the permeability of the plsma membrane to cytosolic proteins without causing release of organelles such as mitochondria into the surrounding medium. Electron microscopy showed that treatment of the cells with increasing concentations of digitonin results in a progressive loss in the continuity of the plasma membrane, while most other aspects of cellular morphology remain normal. Depletion of background staining material from the cytosol by digitonin treatment of the cells greatly enhances the visualization of the cytoskeleton. The use of this technique, together with immunofluorescent light microscopy, has verified the presence of an actin-containing filamentous network at the hepatocyte cortex as well as intermediate filaments distributed throughout the cell. Digitonin is thus useful both for selectively permeabilizing the plasma membrane and for intensifying the appearance of intracellular structures such as microfilaments that are normally difficult to observe in cells such as hepatocytes.

  9. Metabolism of six CYP probe substrates in fetal hepatocytes

    Directory of Open Access Journals (Sweden)

    Abdul Naveed Shaik

    2016-06-01

    Full Text Available Cytochrome P-450 (CYP are the most common drug metabolizing enzymes and are abundantly expressed in liver apart from kidney, lungs, intestine, brain etc. Their expression levels change with physiological conditions and disease states. The expression of these CYPs is less in human foetus and neonates compared to adults, which results in lower clearance of xenobiotics in infants and neonates compared to adults. Hepatocytes are the cells which are largely used to study these CYPs. We have isolated hepatocytes from aborted foetus to study the metabolism of six probe substrates: phenacetin, diclofenac, S-mephenytoin, dextromethorphan, nifedipine and testosterone. The results obtained show the expression of various CYPs (CYP1A2, CYP2C19, CYP2C9, CYP2D6, and CYP3A4 in human foetus and their involvement in metabolism of CYP probe substrates.

  10. [Current status and future perspectives of hepatocyte transplantation].

    Science.gov (United States)

    Pareja, Eugenia; Cortés, Miriam; Gómez-Lechón, M José; Maupoey, Javier; San Juan, Fernando; López, Rafael; Mir, Jose

    2014-02-01

    The imbalance between the number of potential beneficiaries and available organs, originates the search for new therapeutic alternatives, such as Hepatocyte transplantation (HT).Even though this is a treatment option for these patients, the lack of unanimity of criteria regarding indications and technique, different cryopreservation protocols, as well as the different methodology to assess the response to this therapy, highlights the need of a Consensus Conference to standardize criteria and consider future strategies to improve the technique and optimize the results.Our aim is to review and update the current state of hepatocyte transplantation, emphasizing the future research attempting to solve the problems and improve the results of this treatment. Copyright © 2013 AEC. Published by Elsevier Espana. All rights reserved.

  11. Ultrastructure of hepatocyte nuclei in irradiated, adrenalectomized rats

    Energy Technology Data Exchange (ETDEWEB)

    Orkisz, S.; Bartel, H.; Kmiec, B. (Military Medical Academy, Lodz (Poland))

    1984-01-01

    A cytochemical study of hepatocyte nuclei of adrenalectomized and irradiated rats was performed. After irradiation alone, the behaviour of the ribonucleoprotein components was studied according to Bernhard. The findings suggest that a delay occurs in the synthesis of preribosomal RNA in the nucleoli and in the transport of messenger RNA to the cytoplasm. The indirect effect of ionizing radiation on nuclear RNA synthesis is assumed to occur through the influence of cortical steroid hormones on the transcription process.

  12. Insulin-induced CARM1 upregulation facilitates hepatocyte proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Yeom, Chul-gon; Kim, Dong-il; Park, Min-jung; Choi, Joo-hee [College of Veterinary Medicine, Chonnam National University, Gwangju 500-757 (Korea, Republic of); Jeong, Jieun; Wi, Anjin; Park, Whoashig [Jeollanamdo Forest Resources Research Institute, Naju 520-833 (Korea, Republic of); Han, Ho-jae [College of Veterinary Medicine, Seoul National University, Seoul 151-741 (Korea, Republic of); Park, Soo-hyun, E-mail: parksh@chonnam.ac.kr [College of Veterinary Medicine, Chonnam National University, Gwangju 500-757 (Korea, Republic of)

    2015-06-05

    Previously, we reported that CARM1 undergoes ubiquitination-dependent degradation in renal podocytes. It was also reported that CARM1 is necessary for fasting-induced hepatic gluconeogenesis. Based on these reports, we hypothesized that treatment with insulin, a hormone typically present under the ‘fed’ condition, would inhibit gluconeogenesis via CARM1 degradation. HepG2 cells, AML-12 cells, and rat primary hepatocytes were treated with insulin to confirm CARM1 downregulation. Surprisingly, insulin treatment increased CARM1 expression in all cell types examined. Furthermore, treatment with insulin increased histone 3 methylation at arginine 17 and 26 in HepG2 cells. To elucidate the role of insulin-induced CARM1 upregulation, the HA-CARM1 plasmid was transfected into HepG2 cells. CARM1 overexpression did not increase the expression of lipogenic proteins generally increased by insulin signaling. Moreover, CARM1 knockdown did not influence insulin sensitivity. Insulin is known to facilitate hepatic proliferation. Like insulin, CARM1 overexpression increased CDK2 and CDK4 expression. In addition, CARM1 knockdown reduced the number of insulin-induced G2/M phase cells. Moreover, GFP-CARM1 overexpression increased the number of G2/M phase cells. Based on these results, we concluded that insulin-induced CARM1 upregulation facilitates hepatocyte proliferation. These observations indicate that CARM1 plays an important role in liver pathophysiology. - Highlights: • Insulin treatment increases CARM1 expression in hepatocytes. • CARM1 overexpression does not increase the expression of lipogenic proteins. • CARM1 knockdown does not influence insulin sensitivity. • Insulin-induced CARM1 upregulation facilitates hepatocyte proliferation.

  13. Insulin-induced CARM1 upregulation facilitates hepatocyte proliferation

    International Nuclear Information System (INIS)

    Yeom, Chul-gon; Kim, Dong-il; Park, Min-jung; Choi, Joo-hee; Jeong, Jieun; Wi, Anjin; Park, Whoashig; Han, Ho-jae; Park, Soo-hyun

    2015-01-01

    Previously, we reported that CARM1 undergoes ubiquitination-dependent degradation in renal podocytes. It was also reported that CARM1 is necessary for fasting-induced hepatic gluconeogenesis. Based on these reports, we hypothesized that treatment with insulin, a hormone typically present under the ‘fed’ condition, would inhibit gluconeogenesis via CARM1 degradation. HepG2 cells, AML-12 cells, and rat primary hepatocytes were treated with insulin to confirm CARM1 downregulation. Surprisingly, insulin treatment increased CARM1 expression in all cell types examined. Furthermore, treatment with insulin increased histone 3 methylation at arginine 17 and 26 in HepG2 cells. To elucidate the role of insulin-induced CARM1 upregulation, the HA-CARM1 plasmid was transfected into HepG2 cells. CARM1 overexpression did not increase the expression of lipogenic proteins generally increased by insulin signaling. Moreover, CARM1 knockdown did not influence insulin sensitivity. Insulin is known to facilitate hepatic proliferation. Like insulin, CARM1 overexpression increased CDK2 and CDK4 expression. In addition, CARM1 knockdown reduced the number of insulin-induced G2/M phase cells. Moreover, GFP-CARM1 overexpression increased the number of G2/M phase cells. Based on these results, we concluded that insulin-induced CARM1 upregulation facilitates hepatocyte proliferation. These observations indicate that CARM1 plays an important role in liver pathophysiology. - Highlights: • Insulin treatment increases CARM1 expression in hepatocytes. • CARM1 overexpression does not increase the expression of lipogenic proteins. • CARM1 knockdown does not influence insulin sensitivity. • Insulin-induced CARM1 upregulation facilitates hepatocyte proliferation

  14. [Crabtree effect caused by ketoses in isolated rat hepatocytes].

    Science.gov (United States)

    Martínez, P; Carrascosa, J M; Núñez de Castro, I

    1982-01-01

    Oxygen uptake and glycolytic activity were studied in hepatocytes isolated from fed rats. The addition of fructose or tagatose resulted in a 38% and 31% inhibition of cellular respiration respectively. The addition of 10 mM D-glyceraldehyde caused a slight Crabtree effect. Glucose, L-sorbose, or glycerol failed to modify oxygen consumption. Only incubation in the presence of fructose showed a high aerobic glycolysis measured by lactate production.

  15. Hepatocyte polyploidization and its association with pathophysiological processes

    OpenAIRE

    Wang, Min-Jun; Chen, Fei; Lau, Joseph T Y; Hu, Yi-Ping

    2017-01-01

    A characteristic cellular feature of the mammalian liver is the progressive polyploidization of the hepatocytes, where individual cells acquire more than two sets of chromosomes. Polyploidization results from cytokinesis failure that takes place progressively during the course of postnatal development. The proportion of polyploidy also increases with the aging process or with cellular stress such as surgical resection, toxic stimulation, metabolic overload, or oxidative damage, to involve as ...

  16. Functional activity of the rats’ hepatocytes under cancerogenesis

    Directory of Open Access Journals (Sweden)

    V. V. Ivchuk

    2007-10-01

    Full Text Available Enzymatic activity in rat’s hepatocytes under carcinoma Geuren T8 development as well as after introduction of rhenium compounds and cis-platin were studied. It has been determined that the decrease of enzymatic activity contrary to the control animals has been observed under simultaneous injection of cis-platin and cluster rhenium compounds in a liposome form. That confirms possible hepatoprotective properties of the rhenium compounds.

  17. Painting Reproductions on Display

    Directory of Open Access Journals (Sweden)

    Joanna Iranowska

    2017-09-01

    Full Text Available Paintings in museums might occasionally be replaced by a photoprint mimicking the original. This article is an investigation of what constitutes a good reproduction of an artwork (oil painting that is meant to be displayed. The article discusses what the usefulness of reproductions depends on, applying the Valuation Studies approach, which means the primary concern is with the practice of valuing itself. In other words, the study focuses on how museum experts evaluate reproduc-tions of oil paintings. The article analyses three cases of displaying digitally prin-ted copies of Edvard Munch's oil paintings between 2013 and 2015 in the Munch Museum and in the National Gallery in Oslo. The study is based on a series of semi-structured interviews with the experts, working at and for the museums, that were involved in producing and exhibiting of the photoprints: curators, con-servators, museum educators, and external manufacturers. The interviews were grouped into five clusters, which I have chosen to call registers of valuing following Frank Heuts and Annemarie Mol (2013. The described valuation practices have to do with delivering experiences to the public, obtaining mimetic resemblance, solving ethical aspects, exhibitions' budget, and last but not least, with the time perspective.

  18. Unsolicited displays of insights

    DEFF Research Database (Denmark)

    Brouwer, Catherine E.

    2015-01-01

    This study is based on videorecorded interactional data from a specific type of institutional setting which consists of a variety of 'language stimulation activities' for bilingual children in Danish preschools. Bilingual children, with a variety of linguistic backgrounds, take part in these acti......This study is based on videorecorded interactional data from a specific type of institutional setting which consists of a variety of 'language stimulation activities' for bilingual children in Danish preschools. Bilingual children, with a variety of linguistic backgrounds, take part...... in these activities in small groups together with a specialized preschool teacher. One pervasive feature of this kind of data is the ongoing orientation to, and guidance from the adult towards the children on what the main business of their interaction is - what they relevantly are doing. In this light, the paper......: Unsolicited displays may lead to side sequences, they may lead to a shift in the main business of the talk, or they may be explicitly or implicitly ignored. The paper discusses whether and how these unsolicited displays of understanding then can be thought of as leading to opportunities for (language...

  19. A fast and robust hepatocyte quantification algorithm including vein processing

    Directory of Open Access Journals (Sweden)

    Homeyer André

    2010-03-01

    Full Text Available Abstract Background Quantification of different types of cells is often needed for analysis of histological images. In our project, we compute the relative number of proliferating hepatocytes for the evaluation of the regeneration process after partial hepatectomy in normal rat livers. Results Our presented automatic approach for hepatocyte (HC quantification is suitable for the analysis of an entire digitized histological section given in form of a series of images. It is the main part of an automatic hepatocyte quantification tool that allows for the computation of the ratio between the number of proliferating HC-nuclei and the total number of all HC-nuclei for a series of images in one processing run. The processing pipeline allows us to obtain desired and valuable results for a wide range of images with different properties without additional parameter adjustment. Comparing the obtained segmentation results with a manually retrieved segmentation mask which is considered to be the ground truth, we achieve results with sensitivity above 90% and false positive fraction below 15%. Conclusions The proposed automatic procedure gives results with high sensitivity and low false positive fraction and can be applied to process entire stained sections.

  20. Adropin induction of lipoprotein lipase expression in tilapia hepatocytes.

    Science.gov (United States)

    Lian, Anji; Wu, Keqiang; Liu, Tianqiang; Jiang, Nan; Jiang, Quan

    2016-01-01

    The peptide hormone adropin plays a role in energy homeostasis. However, biological actions of adropin in non-mammalian species are still lacking. Using tilapia as a model, we examined the role of adropin in lipoprotein lipase (LPL) regulation in hepatocytes. To this end, the structural identity of tilapia adropin was established by 5'/3'-rapid amplification of cDNA ends (RACE). The transcripts of tilapia adropin were ubiquitously expressed in various tissues with the highest levels in the liver and hypothalamus. The prolonged fasting could elevate tilapia hepatic adropin gene expression, whereas no effect of fasting was observed on hypothalamic adropin gene levels. In primary cultures of tilapia hepatocytes, synthetic adropin was effective in stimulating LPL release, cellular LPL content, and total LPL production. The increase in LPL production also occurred with parallel rises in LPL gene levels. In parallel experiments, adropin could elevate cAMP production and up-regulate protein kinase A (PKA) and PKC activities. Using a pharmacological approach, cAMP/PKA and PLC/inositol trisphosphate (IP3)/PKC cascades were shown to be involved in adropin-stimulated LPL gene expression. Parallel inhibition of p38MAPK and Erk1/2, however, were not effective in these regards. Our findings provide, for the first time, evidence that adropin could stimulate LPL gene expression via direct actions in tilapia hepatocytes through the activation of multiple signaling mechanisms. © 2016 Society for Endocrinology.

  1. Homocysteine inhibits hepatocyte proliferation via endoplasmic reticulum stress.

    Directory of Open Access Journals (Sweden)

    Xue Yu

    Full Text Available Homocysteine is an independent risk factor for coronary, cerebral, and peripheral vascular diseases. Recent studies have shown that levels of homocysteine are elevated in patients with impaired hepatic function, but the precise role of homocysteine in the development of hepatic dysfunction is unclear. In this study, we examined the effect of homocysteine on hepatocyte proliferation in vitro. Our results demonstrated that homocysteine inhibited hepatocyte proliferation by up-regulating protein levels of p53 as well as mRNA and protein levels of p21(Cip1 in primary cultured hepatocytes. Homocysteine induced cell growth arrest in p53-positive hepatocarcinoma cell line HepG2, but not in p53-null hepatocarcinoma cell line Hep3B. A p53 inhibitor pifithrin-α inhibited the expression of p21(Cip1 and attenuated homocysteine-induced cell growth arrest. Homocysteine induced TRB3 expression via endoplasmic reticulum stress pathway, resulting in Akt dephosphorylation. Knock-down of endogenous TRB3 significantly suppressed the inhibitory effect of homocysteine on cell proliferation and the phosphorylation of Akt. LiCl reversed homocysteine-mediated cell growth arrest by inhibiting TRB3-mediated Akt dephosphorylation. These results demonstrate that both TRB3 and p21(Cip1 are critical molecules in the homocysteine signaling cascade and provide a mechanistic explanation for impairment of liver regeneration in hyperhomocysteinemia.

  2. Latest development of display technologies

    International Nuclear Information System (INIS)

    Gao Hong-Yue; Yao Qiu-Xiang; Liu Pan; Zheng Zhi-Qiang; Liu Ji-Cheng; Zheng Hua-Dong; Zeng Chao; Yu Ying-Jie; Sun Tao; Zeng Zhen-Xiang

    2016-01-01

    In this review we will focus on recent progress in the field of two-dimensional (2D) and three-dimensional (3D) display technologies. We present the current display materials and their applications, including organic light-emitting diodes (OLEDs), flexible OLEDs quantum dot light emitting diodes (QLEDs), active-matrix organic light emitting diodes (AMOLEDs), electronic paper (E-paper), curved displays, stereoscopic 3D displays, volumetric 3D displays, light field 3D displays, and holographic 3D displays. Conventional 2D display devices, such as liquid crystal devices (LCDs) often result in ambiguity in high-dimensional data images because of lacking true depth information. This review thus provides a detailed description of 3D display technologies. (topical review)

  3. 3D display system using monocular multiview displays

    Science.gov (United States)

    Sakamoto, Kunio; Saruta, Kazuki; Takeda, Kazutoki

    2002-05-01

    A 3D head mounted display (HMD) system is useful for constructing a virtual space. The authors have researched the virtual-reality systems connected with computer networks for real-time remote control and developed a low-priced real-time 3D display for building these systems. We developed a 3D HMD system using monocular multi-view displays. The 3D displaying technique of this monocular multi-view display is based on the concept of the super multi-view proposed by Kajiki at TAO (Telecommunications Advancement Organization of Japan) in 1996. Our 3D HMD has two monocular multi-view displays (used as a visual display unit) in order to display a picture to the left eye and the right eye. The left and right images are a pair of stereoscopic images for the left and right eyes, then stereoscopic 3D images are observed.

  4. Polymer Dispersed Liquid Crystal Displays

    Science.gov (United States)

    Doane, J. William

    The following sections are included: * INTRODUCTION AND HISTORICAL DEVELOPMENT * PDLC MATERIALS PREPARATION * Polymerization induced phase separation (PIPS) * Thermally induced phase separation (TIPS) * Solvent induced phase separation (SIPS) * Encapsulation (NCAP) * RESPONSE VOLTAGE * Dielectric and resistive effects * Radial configuration * Bipolar configuration * Other director configurations * RESPONSE TIME * DISPLAY CONTRAST * Light scattering and index matching * Incorporation of dyes * Contrast measurements * PDLC DISPLAY DEVICES AND INNOVATIONS * Reflective direct view displays * Large-scale, flexible displays * Switchable windows * Projection displays * High definition spatial light modulator * Haze-free PDLC shutters: wide angle view displays * ENVIRONMENTAL STABILITY * ACKNOWLEDGEMENTS * REFERENCES

  5. Differential Impacts of Soybean and Fish Oils on Hepatocyte Lipid Droplet Accumulation and Endoplasmic Reticulum Stress in Primary Rabbit Hepatocytes

    OpenAIRE

    Zhu, Xueping; Xiao, Zhihui; Xu, Yumin; Zhao, Xingli; Cheng, Ping; Cui, Ningxun; Cui, Mingling; Li, Jie; Zhu, Xiaoli

    2016-01-01

    Parenteral nutrition-associated liver disease (PNALD) is a severe ailment associated with long-term parenteral nutrition. Soybean oil-based lipid emulsions (SOLE) are thought to promote PNALD development, whereas fish oil-based lipid emulsions (FOLE) are thought to protect against PNALD. This study aimed to investigate the effects of SOLE and FOLE on primary rabbit hepatocytes. The results reveal that SOLE caused significant endoplasmic reticulum (ER) and mitochondrial damage, ultimately resu...

  6. Differential Impacts of Soybean and Fish Oils on Hepatocyte Lipid Droplet Accumulation and Endoplasmic Reticulum Stress in Primary Rabbit Hepatocytes

    Directory of Open Access Journals (Sweden)

    Xueping Zhu

    2016-01-01

    Full Text Available Parenteral nutrition-associated liver disease (PNALD is a severe ailment associated with long-term parenteral nutrition. Soybean oil-based lipid emulsions (SOLE are thought to promote PNALD development, whereas fish oil-based lipid emulsions (FOLE are thought to protect against PNALD. This study aimed to investigate the effects of SOLE and FOLE on primary rabbit hepatocytes. The results reveal that SOLE caused significant endoplasmic reticulum (ER and mitochondrial damage, ultimately resulting in lipid droplets accumulation and ER stress. While these deleterious events induce hepatocyte injury, FOLE at high doses cause only minor ER and mitochondrial damage, which has no effect on hepatic function. SOLE also significantly upregulated glucose-regulated protein 94 mRNA and protein expression. These data indicate that SOLE, but not FOLE, damage the ER and mitochondria, resulting in lipid droplets accumulation and ER stress and, finally, hepatocyte injury. This likely contributes to the differential impacts of SOLE and FOLE on PNALD development and progression.

  7. Hepatocyte and keratinocyte growth factors and their receptors in human lung emphysema

    Directory of Open Access Journals (Sweden)

    Marchal Joëlle

    2005-10-01

    Full Text Available Abstract Background Hepatocyte and keratinocyte growth factors are key growth factors in the process of alveolar repair. We hypothesized that excessive alveolar destruction observed in lung emphysema involves impaired expression of hepatocyte and keratinocyte growth factors or their respective receptors, c-met and keratinocyte growth factor receptor. The aim of our study was to compare the expression of hepatocyte and keratinocyte growth factors and their receptors in lung samples from 3 groups of patients: emphysema; smokers without emphysema and non-smokers without emphysema. Methods Hepatocyte and keratinocyte growth factor proteins were analysed by immunoassay and western blot; mRNA expression was measured by real time quantitative polymerase chain reaction. Results Hepatocyte and keratinocyte growth factors, c-met and keratinocyte growth factor receptor mRNA levels were similar in emphysema and non-emphysema patients. Hepatocyte growth factor mRNA correlated negatively with FEV1 and the FEV1/FVC ratio both in emphysema patients and in smokers with or without emphysema. Hepatocyte and keratinocyte growth factor protein concentrations were similar in all patients' groups. Conclusion The expression of hepatocyte and keratinocyte growth factors and their receptors is preserved in patients with lung emphysema as compared to patients without emphysema. Hepatocyte growth factor mRNA correlates with the severity of airflow obstruction in smokers.

  8. DNA synthesis in periportal and perivenous hepatocytes of intact and hepatectomized young mice.

    Science.gov (United States)

    Fernández-Blanco, A; Inda, A M; Errecalde, A L

    2015-01-01

    DNA synthesis of hepatocytes in two areas of Intact and Hepatectomized young mice liver along a circadian period was studied. DNA synthesis was significantly different at all analyzed time points in Intact and Hepatectomized animals. Differences between periportal and perivenous hepatocytes were found in hepatectomized animals at 04/42 and 08/46 hr of day/hour post-hepatectomy. DNAs peak in periportal hepatocytes regenerating liver occurs 4 hr earlier than in perivenous hepatocytes, probably reflecting their shorter G1 phase. Besides, daily mean values of regenerating livers were higher than those observed in Intact animals, as a consequence of surgical removal.

  9. Cholesterol Enhances the Toxic Effect of Ethanol and Acetaldehyde in Primary Mouse Hepatocytes

    Directory of Open Access Journals (Sweden)

    Anayelly López-Islas

    2016-01-01

    Full Text Available Obesity and alcohol consumption are risk factors for hepatic steatosis, and both commonly coexist. Our objective was to evaluate the effect of ethanol and acetaldehyde on primary hepatocytes obtained from mice fed for two days with a high cholesterol (HC diet. HC hepatocytes increased lipid and cholesterol content. HC diet sensitized hepatocytes to the toxic effect of ethanol and acetaldehyde. Cyp2E1 content increased with HC diet, as well as in those treated with ethanol or acetaldehyde, while the activity of this enzyme determined in microsomes increased in the HC and in all ethanol treated hepatocytes, HC and CW. Oxidized proteins were increased in the HC cultures treated or not with the toxins. Transmission electron microscopy showed endoplasmic reticulum (ER stress and megamitochondria in hepatocytes treated with ethanol as in HC and the ethanol HC treated hepatocytes. ER stress determined by PERK content was increased in ethanol treated hepatocytes from HC mice and CW. Nuclear translocation of ATF6 was observed in HC hepatocytes treated with ethanol, results that indicate that lipids overload and ethanol treatment favor ER stress. Oxidative stress, ER stress, and mitochondrial damage underlie potential mechanisms for increased damage in steatotic hepatocyte treated with ethanol.

  10. Lack of direct mitogenic activity of dichloroacetate and trichloroacetate in cultured rat hepatocytes

    International Nuclear Information System (INIS)

    Walgren, Jennie L.; Kurtz, David T.; McMillan, JoEllyn M.

    2005-01-01

    Dichloroacetate (DCA) and trichloroacetate (TCA) are hepatocarcinogenic metabolites of the common groundwater contaminant, 1,1,2-trichloroethylene. DCA and TCA have been shown to induce hepatocyte proliferation in vivo, but it is not known if this response is the result of direct mitogenic activity or whether cell replication occurs indirectly in response to tissue injury or inflammation. In this study we used primary cultures of rat hepatocytes, a species susceptible to DCA- but not TCA-induced hepatocarcinogenesis, to determine whether DCA and TCA are direct hepatocyte mitogens. Rat hepatocytes, cultured in growth factor-free medium, were treated with 0.01-1.0 mM DCA or TCA for 10-40 h; cell replication was then assessed by measuring incorporation of 3 H-thymidine into DNA and by cell counts. DCA or TCA treatment did not alter 3 H-thymidine incorporation in the cultured hepatocytes. Although an increase in cell number was not observed, DCA treatment significantly abrogated the normal background cell loss, suggesting an ability to inhibit apoptotic cell death in primary hepatocyte cultures. Furthermore, treatment with DCA synergistically enhanced the mitogenic response to epidermal growth factor. The data indicate that DCA and TCA are not direct mitogens in hepatocyte cultures, which is of interest in view of their ability to stimulate hepatocyte replication in vivo. Nevertheless, the synergistic enhancement of epidermal growth factor-induced hepatocyte replication by DCA is of particular interest and warrants further study

  11. Gel entrapment culture of rat hepatocytes for investigation of tetracycline-induced toxicity

    International Nuclear Information System (INIS)

    Shen Chong; Meng Qin; Schmelzer, Eva; Bader, Augustinus

    2009-01-01

    This paper aimed to explore three-dimensionally cultured hepatocytes for testing drug-induced nonalcoholic steatohepatitis. Gel entrapped rat hepatocytes were applied for investigation of the tetracycline-induced steatohepatitis, while hepatocyte monolayer was set as a control. The toxic responses of hepatocytes were systematically evaluated by measuring cell viability, liver-specific function, lipid accumulation, oxidative stress, adenosine triphosphate content and mitochondrial membrane potential. The results suggested that gel entrapped hepatocytes showed cell death after 96 h of tetracycline treatment at 25 μM which is equivalent to toxic serum concentration in rats, while hepatocyte monolayer showed cell death at a high dose of 200 μM. The concentration-dependent accumulation of lipid as well as mitochondrial damage were regarded as two early events for tetracycline hepatotoxicity in gel entrapment culture due to their detectability ahead of subsequent increase of oxidative stress and a final cell death. Furthermore, the potent protection of fenofibrate and fructose-1,6-diphosphate were evidenced in only gel entrapment culture with higher expressions on the genes related to β-oxidation than hepatocyte monolayer, suggesting the mediation of lipid metabolism and mitochondrial damage in tetracycline toxicity. Overall, gel entrapped hepatocytes in three-dimension reflected more of the tetracycline toxicity in vivo than hepatocyte monolayer and thus was suggested as a more relevant system for evaluating steatogenic drugs.

  12. Magnetic cell labeling of primary and stem cell-derived pig hepatocytes for MRI-based cell tracking of hepatocyte transplantation.

    Directory of Open Access Journals (Sweden)

    Dwayne R Roach

    Full Text Available Pig hepatocytes are an important investigational tool for optimizing hepatocyte transplantation schemes in both allogeneic and xenogeneic transplant scenarios. MRI can be used to serially monitor the transplanted cells, but only if the hepatocytes can be labeled with a magnetic particle. In this work, we describe culture conditions for magnetic cell labeling of cells from two different pig hepatocyte cell sources; primary pig hepatocytes (ppHEP and stem cell-derived hepatocytes (PICM-19FF. The magnetic particle is a micron-sized iron oxide particle (MPIO that has been extensively studied for magnetic cell labeling for MRI-based cell tracking. ppHEP could endocytose MPIO with labeling percentages as high as 70%, achieving iron content as high as ~55 pg/cell, with >75% viability. PICM-19FF had labeling >97%, achieving iron content ~38 pg/cell, with viability >99%. Extensive morphological and functional assays indicated that magnetic cell labeling was benign to the cells. The results encourage the use of MRI-based cell tracking for the development and clinical use of hepatocyte transplantation methodologies. Further, these results generally highlight the importance of functional cell assays in the evaluation of contrast agent biocompatibility.

  13. Crosstalk evaluation in stereoscopic displays

    NARCIS (Netherlands)

    Wang, L.; Teunissen, C.; Tu, Yan; Chen, Li; Zhang, P.; Zhang, T.; Heynderickx, I.E.J.

    2011-01-01

    Substantial progress in liquid-crystal display and polarization film technology has enabled several types of stereoscopic displays. Despite all progress, some image distortions still exist in these 3-D displays, of which interocular crosstalk - light leakage of the image for one eye to the other eye

  14. LHCb Event display

    CERN Document Server

    Trisovic, Ana

    2014-01-01

    The LHCb Event Display was made for educational purposes at the European Organization for Nuclear Research, CERN in Geneva, Switzerland. The project was implemented as a stand-alone application using C++ and ROOT, a framework developed by CERN for data analysis. This paper outlines the development and architecture of the application in detail, as well as the motivation for the development and the goals of the exercise. The application focuses on the visualization of events recorded by the LHCb detector, where an event represents a set of charged particle tracks in one proton-proton collision. Every particle track is coloured by its type and can be selected to see its essential information such as mass and momentum. The application allows students to save this information and calculate the invariant mass for any pair of particles. Furthermore, the students can use additional calculating tools in the application and build up a histogram of these invariant masses. The goal for the students is to find a $D^0$ par...

  15. Colorimetry for CRT displays.

    Science.gov (United States)

    Golz, Jürgen; MacLeod, Donald I A

    2003-05-01

    We analyze the sources of error in specifying color in CRT displays. These include errors inherent in the use of the color matching functions of the CIE 1931 standard observer when only colorimetric, not radiometric, calibrations are available. We provide transformation coefficients that prove to correct the deficiencies of this observer very well. We consider four different candidate sets of cone sensitivities. Some of these differ substantially; variation among candidate cone sensitivities exceeds the variation among phosphors. Finally, the effects of the recognized forms of observer variation on the visual responses (cone excitations or cone contrasts) generated by CRT stimuli are investigated and quantitatively specified. Cone pigment polymorphism gives rise to variation of a few per cent in relative excitation by the different phosphors--a variation larger than the errors ensuing from the adoption of the CIE standard observer, though smaller than the differences between some candidate cone sensitivities. Macular pigmentation has a larger influence, affecting mainly responses to the blue phosphor. The estimated combined effect of all sources of observer variation is comparable in magnitude with the largest differences between competing cone sensitivity estimates but is not enough to disrupt very seriously the relation between the L and M cone weights and the isoluminance settings of individual observers. It is also comparable with typical instrumental colorimetric errors, but we discuss these only briefly.

  16. Web Extensible Display Manager

    Energy Technology Data Exchange (ETDEWEB)

    Slominski, Ryan [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States); Larrieu, Theodore L. [Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)

    2018-02-01

    Jefferson Lab's Web Extensible Display Manager (WEDM) allows staff to access EDM control system screens from a web browser in remote offices and from mobile devices. Native browser technologies are leveraged to avoid installing and managing software on remote clients such as browser plugins, tunnel applications, or an EDM environment. Since standard network ports are used firewall exceptions are minimized. To avoid security concerns from remote users modifying a control system, WEDM exposes read-only access and basic web authentication can be used to further restrict access. Updates of monitored EPICS channels are delivered via a Web Socket using a web gateway. The software translates EDM description files (denoted with the edl suffix) to HTML with Scalable Vector Graphics (SVG) following the EDM's edl file vector drawing rules to create faithful screen renderings. The WEDM server parses edl files and creates the HTML equivalent in real-time allowing existing screens to work without modification. Alternatively, the familiar drag and drop EDM screen creation tool can be used to create optimized screens sized specifically for smart phones and then rendered by WEDM.

  17. Display systems for NPP control

    International Nuclear Information System (INIS)

    Rozov, S.S.

    1988-01-01

    Main trends in development of display systems used as the means for image displaying in NPP control systems are considered. It is shown that colour display devices appear to be the most universal means for concentrated data presentation. Along with digital means the display systems provide for high-speed response, sufficient for operative control of executive mechanisms. A conclusion is drawn that further development of display systems will move towards creation of large colour fields (on reflection base or with multicolour gas-discharge elements)

  18. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes

    International Nuclear Information System (INIS)

    Hultman, Maria T.; Song, You; Tollefsen, Knut Erik

    2015-01-01

    Highlights: • EE2 induced large scale transcriptional changes in primary hepatocytes. • Classical estrogen biomarkers were altered in a concentration-dependent manner. • EE2 altered biological processes related to lipid transport and reproduction. • EE2 interfered with lipid metabolism, biotransformation, and multidrug transport. • In vitro transcriptional changes were fairly similar to that observed in vivo. - Abstract: The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration–response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48 h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and

  19. 17α-Ethinylestradiol (EE2) effect on global gene expression in primary rainbow trout (Oncorhynchus mykiss) hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Hultman, Maria T., E-mail: mhu@niva.no [Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo (Norway); Faculty of Environmental Science & Technology, Department for Environmental Sciences, Norwegian University of Life Sciences (NMBU), Post box 5003, N-1432 Ås (Norway); Song, You [Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo (Norway); Tollefsen, Knut Erik [Norwegian Institute for Water Research (NIVA), Section of Ecotoxicology and Risk Assessment, Gaustadalléen 21, N-0349 Oslo (Norway); Faculty of Environmental Science & Technology, Department for Environmental Sciences, Norwegian University of Life Sciences (NMBU), Post box 5003, N-1432 Ås (Norway)

    2015-12-15

    Highlights: • EE2 induced large scale transcriptional changes in primary hepatocytes. • Classical estrogen biomarkers were altered in a concentration-dependent manner. • EE2 altered biological processes related to lipid transport and reproduction. • EE2 interfered with lipid metabolism, biotransformation, and multidrug transport. • In vitro transcriptional changes were fairly similar to that observed in vivo. - Abstract: The potential impact of endocrine disrupting chemicals (EDCs) in the aquatic environment has driven the development of screening assays to evaluate the estrogenic properties of chemicals and their effects on aquatic organisms such as fish. However, obtaining full concentration–response relationships in animal (in vivo) exposure studies are laborious, costly and unethical, hence a need for developing feasible alternative (non-animal) methods. Use of in vitro bioassays such as primary fish hepatocytes, which retain many of the native properties of the liver, has been proposed for in vitro screening of estrogen receptor (ER) agonists and antagonists. The aim of present study was to characterize the molecular mode of action (MoA) of the ER agonist 17α-ethinylestradiol (EE2) in primary rainbow trout (Oncorhynchus mykiss) hepatocytes. A custom designed salmonid 60,000-feature (60k) oligonucleotide microarray was used to characterize the potential MoAs after 48 h exposure to EE2. The microarray analysis revealed several concentration-dependent gene expression alterations including classical estrogen sensitive biomarker gene expression (e.g. estrogen receptor α, vitellogenin, zona radiata). Gene Ontology (GO) analysis displayed transcriptional changes suggesting interference of cellular growth, fatty acid and lipid metabolism potentially mediated through the estrogen receptor (ER), which were proposed to be associated with modulation of genes involved in endocrine function and reproduction. Pathway analysis supported the identified GOs and

  20. Manganese Transport and Toxicity in Polarized WIF-B Hepatocytes.

    Science.gov (United States)

    Thompson, Khristy J; Hein, Jennifer; Baez, Andrew; Sosa, Jose Carlo; Wessling-Resnick, Marianne

    2018-05-24

    Mn toxicity arises from nutritional problems, community and occupational exposures, and genetic risks. Mn blood levels are controlled by hepatobiliary clearance. The goals of this study were to determine the cellular distribution of Mn transporters in polarized hepatocytes, to establish an in vitro assay for hepatocyte Mn efflux, and to examine possible roles the Mn transporters would play in metal import and export. For these experiments, hepatocytoma WIF-B cells were grown for 12-14 days to achieve maximal polarity. Immunoblots showed that Mn transporters ZIP8, ZnT10, ferroportin (Fpn), and ZIP14 were present. Indirect immunofluorescence microscopy localized Fpn and ZIP14 to WIF-B cell basolateral domains while ZnT10 and ZIP8 associated with intracellular vesicular compartments. ZIP8-positive structures were distributed uniformly throughout the cytoplasm, but ZnT10-positive vesicles were adjacent to apical bile compartments. WIF-B cells were sensitive to Mn toxicity, showing decreased viability after 16 h exposure to > 250 M MnCl2. However, the hepatocytes were resistant to 4 h exposures of up to 500 M MnCl2 despite 50-fold increased Mn content. Washout experiments showed time-dependent efflux with 80% Mn released after a 4 h chase period. Hepcidin reduced levels of Fpn in WIF-B cells, clearing Fpn from the cell surface, but Mn efflux was unaffected. The secretory inhibitor brefeldin A did block release of Mn from WIF-B cells, suggesting vesicle fusion may be involved in export. These results point to a possible role of ZnT10 to import Mn into vesicles that subsequently fuse with the apical membrane and empty their contents into bile.

  1. Curcumin inhibits activation of TRPM2 channels in rat hepatocytes

    Directory of Open Access Journals (Sweden)

    E. Kheradpezhouh

    2016-04-01

    Full Text Available Oxidative stress is a hallmark of many liver diseases including viral and drug-induced hepatitis, ischemia-reperfusion injury, and non-alcoholic steatohepatitis. One of the consequences of oxidative stress in the liver is deregulation of Ca2+ homeostasis, resulting in a sustained elevation of the free cytosolic Ca2+ concentration ([Ca2+]c in hepatocytes, which leads to irreversible cellular damage. Recently it has been shown that liver damage induced by paracetamol and subsequent oxidative stress is, in large part, mediated by Ca2+ entry through Transient Receptor Potential Melastatin 2 (TRPM2 channels. Involvement of TRPM2 channels in hepatocellular damage induced by oxidative stress makes TRPM2 a potential therapeutic target for treatment of a range of oxidative stress-related liver diseases. We report here the identification of curcumin ((1E,6E-1,7-bis(4-hydroxy-3-methoxyphenyl-1,6-heptadiene-3,5-dione, a natural plant-derived polyphenol in turmeric spice, as a novel inhibitor of TRPM2 channel. Presence of 5 µM curcumin in the incubation medium prevented the H2O2- and paracetamol-induced [Ca2+]c rise in rat hepatocytes. Furthermore, in patch clamping experiments incubation of hepatocytes with curcumin inhibited activation of TRPM2 current by intracellular ADPR with IC50 of approximately 50 nM. These findings enhance understanding of the actions of curcumin and suggest that the known hepatoprotective properties of curcumin are, at least in part, mediated through inhibition of TRPM2 channels.

  2. Predictivity of dog co-culture model, primary human hepatocytes and HepG2 cells for the detection of hepatotoxic drugs in humans

    International Nuclear Information System (INIS)

    Atienzar, Franck A.; Novik, Eric I.; Gerets, Helga H.; Parekh, Amit; Delatour, Claude; Cardenas, Alvaro; MacDonald, James; Yarmush, Martin L.; Dhalluin, Stéphane

    2014-01-01

    Drug Induced Liver Injury (DILI) is a major cause of attrition during early and late stage drug development. Consequently, there is a need to develop better in vitro primary hepatocyte models from different species for predicting hepatotoxicity in both animals and humans early in drug development. Dog is often chosen as the non-rodent species for toxicology studies. Unfortunately, dog in vitro models allowing long term cultures are not available. The objective of the present manuscript is to describe the development of a co-culture dog model for predicting hepatotoxic drugs in humans and to compare the predictivity of the canine model along with primary human hepatocytes and HepG2 cells. After rigorous optimization, the dog co-culture model displayed metabolic capacities that were maintained up to 2 weeks which indicates that such model could be also used for long term metabolism studies. Most of the human hepatotoxic drugs were detected with a sensitivity of approximately 80% (n = 40) for the three cellular models. Nevertheless, the specificity was low approximately 40% for the HepG2 cells and hepatocytes compared to 72.7% for the canine model (n = 11). Furthermore, the dog co-culture model showed a higher superiority for the classification of 5 pairs of close structural analogs with different DILI concerns in comparison to both human cellular models. Finally, the reproducibility of the canine system was also satisfactory with a coefficient of correlation of 75.2% (n = 14). Overall, the present manuscript indicates that the dog co-culture model may represent a relevant tool to perform chronic hepatotoxicity and metabolism studies. - Highlights: • Importance of species differences in drug development. • Relevance of dog co-culture model for metabolism and toxicology studies. • Hepatotoxicity: higher predictivity of dog co-culture vs HepG2 and human hepatocytes

  3. Predictivity of dog co-culture model, primary human hepatocytes and HepG2 cells for the detection of hepatotoxic drugs in humans

    Energy Technology Data Exchange (ETDEWEB)

    Atienzar, Franck A., E-mail: franck.atienzar@ucb.com [UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l' Alleud (Belgium); Novik, Eric I. [H mu rel Corporation, 675 U.S. Highway 1, North Brunswick, NJ 08902 (United States); Gerets, Helga H. [UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l' Alleud (Belgium); Parekh, Amit [H mu rel Corporation, 675 U.S. Highway 1, North Brunswick, NJ 08902 (United States); Delatour, Claude; Cardenas, Alvaro [UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l' Alleud (Belgium); MacDonald, James [Chrysalis Pharma Consulting, LLC, 385 Route 24, Suite 1G, Chester, NJ 07930 (United States); Yarmush, Martin L. [Department of Biomedical Engineering, Rutgers University, Piscataway, NJ 08854 (United States); Dhalluin, Stéphane [UCB Pharma SA, Non-Clinical Development, Chemin du Foriest, 1420 Braine-l' Alleud (Belgium)

    2014-02-15

    Drug Induced Liver Injury (DILI) is a major cause of attrition during early and late stage drug development. Consequently, there is a need to develop better in vitro primary hepatocyte models from different species for predicting hepatotoxicity in both animals and humans early in drug development. Dog is often chosen as the non-rodent species for toxicology studies. Unfortunately, dog in vitro models allowing long term cultures are not available. The objective of the present manuscript is to describe the development of a co-culture dog model for predicting hepatotoxic drugs in humans and to compare the predictivity of the canine model along with primary human hepatocytes and HepG2 cells. After rigorous optimization, the dog co-culture model displayed metabolic capacities that were maintained up to 2 weeks which indicates that such model could be also used for long term metabolism studies. Most of the human hepatotoxic drugs were detected with a sensitivity of approximately 80% (n = 40) for the three cellular models. Nevertheless, the specificity was low approximately 40% for the HepG2 cells and hepatocytes compared to 72.7% for the canine model (n = 11). Furthermore, the dog co-culture model showed a higher superiority for the classification of 5 pairs of close structural analogs with different DILI concerns in comparison to both human cellular models. Finally, the reproducibility of the canine system was also satisfactory with a coefficient of correlation of 75.2% (n = 14). Overall, the present manuscript indicates that the dog co-culture model may represent a relevant tool to perform chronic hepatotoxicity and metabolism studies. - Highlights: • Importance of species differences in drug development. • Relevance of dog co-culture model for metabolism and toxicology studies. • Hepatotoxicity: higher predictivity of dog co-culture vs HepG2 and human hepatocytes.

  4. Augmenting digital displays with computation

    Science.gov (United States)

    Liu, Jing

    As we inevitably step deeper and deeper into a world connected via the Internet, more and more information will be exchanged digitally. Displays are the interface between digital information and each individual. Naturally, one fundamental goal of displays is to reproduce information as realistically as possible since humans still care a lot about what happens in the real world. Human eyes are the receiving end of such information exchange; therefore it is impossible to study displays without studying the human visual system. In fact, the design of displays is rather closely coupled with what human eyes are capable of perceiving. For example, we are less interested in building displays that emit light in the invisible spectrum. This dissertation explores how we can augment displays with computation, which takes both display hardware and the human visual system into consideration. Four novel projects on display technologies are included in this dissertation: First, we propose a software-based approach to driving multiview autostereoscopic displays. Our display algorithm can dynamically assign views to hardware display zones based on multiple observers' current head positions, substantially reducing crosstalk and stereo inversion. Second, we present a dense projector array that creates a seamless 3D viewing experience for multiple viewers. We smoothly interpolate the set of viewer heights and distances on a per-vertex basis across the arrays field of view, reducing image distortion, crosstalk, and artifacts from tracking errors. Third, we propose a method for high dynamic range display calibration that takes into account the variation of the chrominance error over luminance. We propose a data structure for enabling efficient representation and querying of the calibration function, which also allows user-guided balancing between memory consumption and the amount of computation. Fourth, we present user studies that demonstrate that the ˜ 60 Hz critical flicker fusion

  5. Naked gene therapy of hepatocyte growth factor for dextran sulfate sodium-induced colitis in mice

    International Nuclear Information System (INIS)

    Kanbe, Takamasa; Murai, Rie; Mukoyama, Tomoyuki; Murawaki, Yoshiyuki; Hashiguchi, Ko-ichi; Yoshida, Yoko; Tsuchiya, Hiroyuki; Kurimasa, Akihiro; Harada, Ken-ichi; Yashima, Kazuo; Nishimuki, Eiji; Shabana, Noriko; Kishimoto, Yukihiro; Kojyo, Haruhiko; Miura, Kunihiko; Murawaki, Yoshikazu; Kawasaki, Hironaka; Shiota, Goshi

    2006-01-01

    Ulcerative colitis (UC) is progressive and relapsing disease. To explore the therapeutic effects of naked gene therapy of hepatocyte growth factor (HGF) on UC, the SRα promoter driving HGF gene was intrarectally administered to the mice in which colitis was induced by dextran sulfate sodium (DSS). Expression of the transgene was seen in surface epithelium, lamina propria, and muscularis mucosae. The HGF-treated mice showed reduced colonic mucosal damage and increased body weights, compared with control mice (P < 0.01 and P < 0.05, respectively). The HGF-treated mice displayed increased number of PCNA-positive cells and decreased number of apoptotic cells than in control mice (P < 0.01, each). Phosphorylated AKT was dramatically increased after HGF gene administration, however, phosphorylated ERK1/2 was not altered. Microarray analysis revealed that HGF induced expression of proliferation- and apoptosis-associated genes. These data suggest that naked HGF gene delivery causes therapeutic effects through regulation of many downstream genes

  6. Display Parameters and Requirements

    Science.gov (United States)

    Bahadur, Birendra

    The following sections are included: * INTRODUCTION * HUMAN FACTORS * Anthropometry * Sensory * Cognitive * Discussions * THE HUMAN VISUAL SYSTEM - CAPABILITIES AND LIMITATIONS * Cornea * Pupil and Iris * Lens * Vitreous Humor * Retina * RODS - NIGHT VISION * CONES - DAY VISION * RODS AND CONES - TWILIGHT VISION * VISUAL PIGMENTS * MACULA * BLOOD * CHOROID COAT * Visual Signal Processing * Pathways to the Brain * Spatial Vision * Temporal Vision * Colour Vision * Colour Blindness * DICHROMATISM * Protanopia * Deuteranopia * Tritanopia * ANOMALOUS TRICHROMATISM * Protanomaly * Deuteranomaly * Tritanomaly * CONE MONOCHROMATISM * ROD MONOCHROMATISM * Using Colour Effectively * COLOUR MIXTURES AND THE CHROMATICITY DIAGRAM * Colour Matching Functions and Chromaticity Co-ordinates * CIE 1931 Colour Space * CIE PRIMARIES * CIE COLOUR MATCHING FUNCTIONS AND CHROMATICITY CO-ORDINATES * METHODS FOR DETERMINING TRISTIMULUS VALUES AND COLOUR CO-ORDINATES * Spectral Power Distribution Method * Filter Method * CIE 1931 CHROMATICITY DIAGRAM * ADDITIVE COLOUR MIXTURE * CIE 1976 Chromaticity Diagram * CIE Uniform Colour Spaces and Colour Difference Formulae * CIELUV OR L*u*v* * CIELAB OR L*a*b* * CIE COLOUR DIFFERENCE FORMULAE * Colour Temperature and CIE Standard Illuminants and source * RADIOMETRIC AND PHOTOMETRIC QUANTITIES * Photopic (Vλ and Scotopic (Vλ') Luminous Efficiency Function * Photometric and Radiometric Flux * Luminous and Radiant Intensities * Incidence: Illuminance and Irradiance * Exitance or Emittance (M) * Luminance and Radiance * ERGONOMIC REQUIREMENTS OF DISPLAYS * ELECTRO-OPTICAL PARAMETERS AND REQUIREMENTS * Contrast and Contrast Ratio * Luminance and Brightness * Colour Contrast and Chromaticity * Glare * Other Aspects of Legibility * SHAPE AND SIZE OF CHARACTERS * DEFECTS AND BLEMISHES * FLICKER AND DISTORTION * ANGLE OF VIEW * Switching Speed * Threshold and Threshold Characteristic * Measurement Techniques For Electro-optical Parameters * RADIOMETRIC

  7. A Cell Culture Platform to Maintain Long-term Phenotype of Primary Human Hepatocytes and Endothelial Cells.

    Science.gov (United States)

    Ware, Brenton R; Durham, Mitchell J; Monckton, Chase P; Khetani, Salman R

    2018-03-01

    Modeling interactions between primary human hepatocytes (PHHs) and primary human liver sinusoidal endothelial cells (LSECs) in vitro can help elucidate human-specific mechanisms underlying liver physiology/disease and drug responses; however, existing hepatocyte/endothelial coculture models are suboptimal because of their use of rodent cells, cancerous cell lines, and/or nonliver endothelial cells. Hence, we sought to develop a platform that could maintain the long-term phenotype of PHHs and primary human LSECs. Primary human LSECs or human umbilical vein endothelial cells as the nonliver control were cocultivated with micropatterned PHH colonies (to control homotypic interactions) followed by an assessment of PHH morphology and functions (albumin and urea secretion, and cytochrome P-450 2A6 and 3A4 enzyme activities) over 3 weeks. Endothelial phenotype was assessed via gene expression patterns and scanning electron microscopy to visualize fenestrations. Hepatic responses in PHH/endothelial cocultures were benchmarked against responses in previously developed PHH/3T3-J2 fibroblast cocultures. Finally, PHH/fibroblast/endothelial cell tricultures were created and characterized as described previously. LSECs, but not human umbilical vein endothelial cells, induced PHH albumin secretion for ∼11 days; however, neither endothelial cell type could maintain PHH morphology and functions to the same magnitude/longevity as the fibroblasts. In contrast, both PHHs and endothelial cells displayed stable phenotype for 3 weeks in PHH/fibroblast/endothelial cell tricultures; furthermore, layered tricultures in which PHHs and endothelial cells were separated by a protein gel to mimic the space of Disse displayed similar functional levels as the coplanar tricultures. PHH/fibroblast/endothelial tricultures constitute a robust platform to elucidate reciprocal interactions between PHHs and endothelial cells in physiology, disease, and after drug exposure.

  8. High throughput micro-well generation of hepatocyte micro-aggregates for tissue engineering.

    Directory of Open Access Journals (Sweden)

    Elien Gevaert

    Full Text Available The main challenge in hepatic tissue engineering is the fast dedifferentiation of primary hepatocytes in vitro. One successful approach to maintain hepatocyte phenotype on the longer term is the cultivation of cells as aggregates. This paper demonstrates the use of an agarose micro-well chip for the high throughput generation of hepatocyte aggregates, uniform in size. In our study we observed that aggregation of hepatocytes had a beneficial effect on the expression of certain hepatocyte specific markers. Moreover we observed that the beneficial effect was dependent on the aggregate dimensions, indicating that aggregate parameters should be carefully considered. In a second part of the study, the selected aggregates were immobilized by encapsulation in methacrylamide-modified gelatin. Phenotype evaluations revealed that a stable hepatocyte phenotype could be maintained during 21 days when encapsulated in the hydrogel. In conclusion we have demonstrated the beneficial use of micro-well chips for hepatocyte aggregation and the size-dependent effects on hepatocyte phenotype. We also pointed out that methacrylamide-modified gelatin is suitable for the encapsulation of these aggregates.

  9. High Throughput Micro-Well Generation of Hepatocyte Micro-Aggregates for Tissue Engineering

    NARCIS (Netherlands)

    Gevaert, Elien; Dollé, Laurent; Billiet, Thomas; Dubruel, Peter; van Grunsven, Leo; van Apeldoorn, Aart A.; Cornelissen, Ria

    2014-01-01

    The main challenge in hepatic tissue engineering is the fast dedifferentiation of primary hepatocytes in vitro. One successful approach to maintain hepatocyte phenotype on the longer term is the cultivation of cells as aggregates. This paper demonstrates the use of an agarose micro-well chip for the

  10. Integrin-linked kinase is involved in matrix-induced hepatocyte differentiation

    International Nuclear Information System (INIS)

    Gkretsi, Vasiliki; Bowen, William C.; Yang, Yu; Wu, Chuanyue; Michalopoulos, George K.

    2007-01-01

    Hepatocytes have restricted proliferative capacity in culture and when cultured without matrix, lose the hepatocyte-specific gene expression and characteristic cellular micro-architecture. Overlay of matrix-preparations on de-differentiated hepatocytes restores differentiation. Integrin-linked kinase (ILK) is a cell-matrix-adhesion protein crucial in fundamental processes such as differentiation and survival. In this study, we investigated the role of ILK, and its binding partners PINCH, α-parvin, and Mig-2 in matrix-induced hepatocyte differentiation. We report here that ILK is present in the liver and localizes at cell-matrix adhesions of cultured hepatocytes. We also show that ILK, PINCH, α-parvin, and Mig-2 expression level is dramatically reduced in the re-differentiated hepatocytes. Interestingly, hepatocytes lacking ILK undergo matrix-induced differentiation but their differentiation is incomplete, as judged by monitoring cell morphology and production of albumin. Our results show that ILK and cell-matrix adhesion proteins play an important role in the process of matrix-induced hepatocyte differentiation

  11. High throughput micro-well generation of hepatocyte micro-aggregates for tissue engineering.

    Science.gov (United States)

    Gevaert, Elien; Dollé, Laurent; Billiet, Thomas; Dubruel, Peter; van Grunsven, Leo; van Apeldoorn, Aart; Cornelissen, Ria

    2014-01-01

    The main challenge in hepatic tissue engineering is the fast dedifferentiation of primary hepatocytes in vitro. One successful approach to maintain hepatocyte phenotype on the longer term is the cultivation of cells as aggregates. This paper demonstrates the use of an agarose micro-well chip for the high throughput generation of hepatocyte aggregates, uniform in size. In our study we observed that aggregation of hepatocytes had a beneficial effect on the expression of certain hepatocyte specific markers. Moreover we observed that the beneficial effect was dependent on the aggregate dimensions, indicating that aggregate parameters should be carefully considered. In a second part of the study, the selected aggregates were immobilized by encapsulation in methacrylamide-modified gelatin. Phenotype evaluations revealed that a stable hepatocyte phenotype could be maintained during 21 days when encapsulated in the hydrogel. In conclusion we have demonstrated the beneficial use of micro-well chips for hepatocyte aggregation and the size-dependent effects on hepatocyte phenotype. We also pointed out that methacrylamide-modified gelatin is suitable for the encapsulation of these aggregates.

  12. Computational Topology Based Quantification Of Hepatocytes Nuclei In Lipopolysaccharide-Induced Liver Injury In Mice

    Directory of Open Access Journals (Sweden)

    Rodrigo Rojas Moraleda

    2016-06-01

    The computational topology approach proposed successfully detected hepatocyte cells under several natural variations. We evaluated on a per-pixel basis how the segmentation performs on: i all nuclei in the images, ii big round nuclei considered belonging to hepatocytes cells (accuracy 87.2%, recall 80.3%, and iii nuclei regarded to non-parenchymal cells.  

  13. Laser illuminated flat panel display

    Energy Technology Data Exchange (ETDEWEB)

    Veligdan, J.T.

    1995-12-31

    A 10 inch laser illuminated flat panel Planar Optic Display (POD) screen has been constructed and tested. This POD screen technology is an entirely new concept in display technology. Although the initial display is flat and made of glass, this technology lends itself to applications where a plastic display might be wrapped around the viewer. The display screen is comprised of hundreds of planar optical waveguides where each glass waveguide represents a vertical line of resolution. A black cladding layer, having a lower index of refraction, is placed between each waveguide layer. Since the cladding makes the screen surface black, the contrast is high. The prototype display is 9 inches wide by 5 inches high and approximately I inch thick. A 3 milliwatt HeNe laser is used as the illumination source and a vector scanning technique is employed.

  14. Extracellular matrix components influence DNA synthesis of rat hepatocytes in primary culture

    International Nuclear Information System (INIS)

    Sawada, N.; Tomomura, A.; Sattler, C.A.; Sattler, G.L.; Kleinman, H.K.; Pitot, H.C.

    1986-01-01

    The effects of several extracellular matrix components (EMCs) - fibronectin (Fn), laminin (Ln), type I (C-I) and type IV (C-IV) collagen - on DNA synthesis in rat hepatocytes in primary culture were examined by both quantitative scintillation spectrometry and autoradiography of [ 3 H]thymidine incorporation. Hepatocytes cultured on Fn showed the most active DNA synthesis initiated by epidermal growth factor (EGF) with decreasing levels of [ 3 H]thymidine uptake exhibited in the cell cultured on C-IV, C-I, and Ln, respectively. The decreasing level of DNA synthesis in hepatocytes cultured on Fn, C-IV, C-I, and Ln respectively was not influenced by cell density. The number of EGF receptors of hepatocytes was also not influenced by EMCs. These data suggest that EMCs modify hepatocyte DNA synthesis by means of post-EGF-receptor mechanisms which are regulated by both growth factors and cell density

  15. The role of hepatocyte nuclear factor 4 alpha in development and progression of liver diseases

    Directory of Open Access Journals (Sweden)

    YANG Jinlian

    2016-02-01

    Full Text Available Hepatocyte nuclear factor 4 alpha (HNF4α, a member of the nuclear receptor superfamily, has a high expression level in mature hepatocytes. HNF4α can regulate hepatocyte-specific gene expression at a transcriptional level, promote hepatocyte development and differentiation, participate in establishment and maintenance of hepatocyte polarity, and enhance the synthetic, metabolic, and detoxifying functions of the liver. Through inhibiting the activation of hepatic stellate cells, reversing epithelial-mesenchymal transition, and inhibiting the proliferation, invasion, and metastasis of hepatoma cells, HNF4α may be involved in the development and progression of various liver diseases including liver fibrosis, liver cirrhosis, and hepatocellular carcinoma. This paper elaborates on the biological functions of HNF4α, and summarizes and analyzes the research advances in the mechanisms of action of HNF4α in the pathological process of liver diseases, in order to provide references for further investigation of the potential targeted therapies for liver diseases.

  16. Flat panel planar optic display

    Energy Technology Data Exchange (ETDEWEB)

    Veligdan, J.T. [Brookhaven National Lab., Upton, NY (United States). Dept. of Advanced Technology

    1994-11-01

    A prototype 10 inch flat panel Planar Optic Display, (POD), screen has been constructed and tested. This display screen is comprised of hundreds of planar optic class sheets bonded together with a cladding layer between each sheet where each glass sheet represents a vertical line of resolution. The display is 9 inches wide by 5 inches high and approximately 1 inch thick. A 3 milliwatt HeNe laser is used as the illumination source and a vector scanning technique is employed.

  17. Galactosylated DNA lipid nanocapsules for efficient hepatocyte targeting.

    Science.gov (United States)

    Morille, M; Passirani, C; Letrou-Bonneval, E; Benoit, J-P; Pitard, B

    2009-09-11

    The main objective of gene therapy via a systemic pathway is the development of a stable and non-toxic gene vector that can encapsulate and deliver foreign genetic materials into specific cell types with the transfection efficiency of viral vectors. With this objective, DNA complexed with cationic lipids of DOTAP/DOPE was encapsulated into lipid nanocapsules (LNCs) forming nanocarriers (DNA LNCs) with a size suitable for systemic injection (109+/-6 nm). With the goal of increasing systemic delivery, LNCs were stabilised with long chains of poly(ethylene glycol) (PEG), either from a PEG lipid derivative (DSPE-mPEG(2000)) or from an amphiphilic block copolymer (F108). In order to overcome internalisation difficulties encountered with PEG shield, a specific ligand (galactose) was covalently added at the distal end of the PEG chains, in order to provide active targeting of the asialoglycoprotein-receptor present on hepatocytes. This study showed that DNA LNCs were as efficient as positively charged DOTAP/DOPE lipoplexes for transfection. In primary hepatocytes, when non-galactosylated, the two polymers significantly decreased the transfection, probably by creating a barrier around the DNA LNCs. Interestingly, galactosylated F108 coated DNA LNCs led to a 18-fold increase in luciferase expression compared to non-galactosylated ones.

  18. Study of Valproic Acid-Enhanced Hepatocyte Steatosis

    Science.gov (United States)

    Chang, Renin; Chou, Mei-Chia; Hung, Li-Ying; Wang, Mu-En; Hsu, Meng-Chieh; Chiu, Chih-Hsien

    2016-01-01

    Valproic acid (VPA) is one of the most widely used antiepilepsy drugs. However, several side effects, including weight gain and fatty liver, have been reported in patients following VPA treatment. In this study, we explored the molecular mechanisms of VPA-induced hepatic steatosis using FL83B cell line-based in vitro model. Using fluorescent lipid staining technique, we found that VPA enhanced oleic acid- (OLA-) induced lipid accumulation in a dose-dependent manner in hepatocytes; this may be due to upregulated lipid uptake, triacylglycerol (TAG) synthesis, and lipid droplet formation. Real-time PCR results showed that, following VPA treatment, the expression levels of genes encoding cluster of differentiation 36 (Cd36), low-density lipoprotein receptor-related protein 1 (Lrp1), diacylglycerol acyltransferase 2 (Dgat2), and perilipin 2 (Plin2) were increased, that of carnitine palmitoyltransferase I a (Cpt1a) was not affected, and those of acetyl-Co A carboxylase α (Acca) and fatty acid synthase (Fasn) were decreased. Furthermore, using immunofluorescence staining and flow cytometry analyses, we found that VPA also induced peroxisome proliferator-activated receptor γ (PPARγ) nuclear translocation and increased levels of cell-surface CD36. Based on these results, we propose that VPA may enhance OLA-induced hepatocyte steatosis through the upregulation of PPARγ- and CD36-dependent lipid uptake, TAG synthesis, and lipid droplet formation. PMID:27034954

  19. Study of Valproic Acid-Enhanced Hepatocyte Steatosis

    Directory of Open Access Journals (Sweden)

    Renin Chang

    2016-01-01

    Full Text Available Valproic acid (VPA is one of the most widely used antiepilepsy drugs. However, several side effects, including weight gain and fatty liver, have been reported in patients following VPA treatment. In this study, we explored the molecular mechanisms of VPA-induced hepatic steatosis using FL83B cell line-based in vitro model. Using fluorescent lipid staining technique, we found that VPA enhanced oleic acid- (OLA- induced lipid accumulation in a dose-dependent manner in hepatocytes; this may be due to upregulated lipid uptake, triacylglycerol (TAG synthesis, and lipid droplet formation. Real-time PCR results showed that, following VPA treatment, the expression levels of genes encoding cluster of differentiation 36 (Cd36, low-density lipoprotein receptor-related protein 1 (Lrp1, diacylglycerol acyltransferase 2 (Dgat2, and perilipin 2 (Plin2 were increased, that of carnitine palmitoyltransferase I a (Cpt1a was not affected, and those of acetyl-Co A carboxylase α (Acca and fatty acid synthase (Fasn were decreased. Furthermore, using immunofluorescence staining and flow cytometry analyses, we found that VPA also induced peroxisome proliferator-activated receptor γ (PPARγ nuclear translocation and increased levels of cell-surface CD36. Based on these results, we propose that VPA may enhance OLA-induced hepatocyte steatosis through the upregulation of PPARγ- and CD36-dependent lipid uptake, TAG synthesis, and lipid droplet formation.

  20. Transport of heparan sulfate into the nuclei of hepatocytes

    International Nuclear Information System (INIS)

    Ishihara, M.; Fedarko, N.S.; Conrad, H.E.

    1986-01-01

    A rat hepatocyte cell line which accumulates free heparan sulfate (HS) chains enriched in GlcA-2-SO 4 residues in the nucleus was labeled with 35 SO 4 2- and the rate of appearance of [ 35 SO 4 ]HS in the nucleus was measured. [ 35 SO 4 ]HS began to accumulate in the nucleus 2 h after the addition of 35 SO 42- and reached a steady state level after 20 h. HS was lost from the nuclei of prelabeled cells with a t/sub 1/2/ of 8 h. Chloroquine did not inhibit the transport of HS into the nucleus, but increased the t/sub 1/2/ for the exit of HS from the nucleus to 20 h. At both 37 0 C and 16 0 C exogenous [ 35 SO 4 ]proteoHS was taken up by the cells and converted to free chains and about 10% of the internalized [ 35 SO 4 ]HS was transported into the nucleus. The [ 35 SO 4 ]HS isolated from the nucleus was enriched in GlcA-2-SO 4 residues, whereas the [ 35 SO 4 ]HS remaining in the rest of the intra-cellular pool showed a corresponding depletion in GlcA-2-SO 4 residues. The results show that nuclear HS is derived from the pool of a secreted proteoHS and that metabolism of exogenous HS by hepatocytes does not involve lysosomal processing of the internalized HS

  1. Biotransformation of hydralazine (HDZ) in monolayer cultures of rabbit hepatocytes

    International Nuclear Information System (INIS)

    McQueen, C.A.; Rosado, R.R.

    1990-01-01

    Adverse reactions to HDZ have been associated with the acetylator polymorphism; slow acetylators are more likely to develop HDZ-induced lupus erythematosus. In studying the role of this polymorphism in susceptibility to HDZ toxicity, the biotransformation of HDZ was investigated in rabbit hepatocytes. New Zealand white rabbits, like humans, are classified as rapid or slow acetylators. Heptocytes were isolated from rapid acetylator rabbits by collagenase perfusion. Monolayer cultures were initiated and exposed to 14 C-HDZ. Since HDZ is unstable at neutral pH, parallel incubations were done in the absence of cells. Metabolites in the media were determined by reverse phase HPLC. Phthalazine (P), phthalazinone (PZ), triazoloph-thalazine (TP), methyl TP (MTP) and 3-hydroxy MTP were identified. In the absence of cells, more TP was formed than MTP, probably resulting from reaction of HDZ with components in the medium. In the presence of cells, there was a three-fold increase in MTP, while the amount of TP was relatively constant. Only trace amounts of P, PZ 3-hydroxy MTP were detected. These data indicate that monolayer cultures of rapid acetylator rabbit hepatocytes were capable of metabolizing HDZ with acetylation playing a major role. These studies are being extended to cells from slow acetylator rabbits

  2. Rapid and sensitive measure of gluconeogenesis in isolated bovine hepatocytes

    International Nuclear Information System (INIS)

    Azain, M.J.; Kasser, T.R.; Atwell, C.A.; Baile, C.A.

    1986-01-01

    Available methods for determining glucose synthesis from radiolabelled precursors using ion exchange column chromatography limit the number of samples that can be processed. To facilitate this process, a rapid method for determining glucose synthesis from 3-carbon precursors was developed using suspensions of anion and cation exchange resins. Hepatocytes were prepared from calf liver by collagenase perfusion of the caudate lobe. Isolated cells were incubated with 14 C-labelled lactate or propionate in the presence or absence of glucagen and/or palmitate. Glucose synthesis was determined by vortexing an aliquot of cell suspension with a 50% slurry of anion exchange resin (acetate form), followed by cation exchange resin. After centrifugation 14 C-glucose was recovered in the supernatant and measured by scintillation counting. Using this method, more than 95% of unused labelled precursor was bound to the ion exchange resin and essentially 100% of 14 C-glucose tracer was recovered in the supernatant. In hepatocyte suspensions, radioactivity recovered in the supernatants was confirmed to be glucose by pre-incubating aliquots of media with glucose oxidase prior to addition of ion exchange resins. The present system allows determination of hepatic gluconeogenesis, is sensitive to substrate and hormonal manipulations and has the capacity for processing several hundred samples per day

  3. Stimulation of glucose phosphorylation by fructose in isolated rat hepatocytes.

    Science.gov (United States)

    Van Schaftingen, E; Vandercammen, A

    1989-01-15

    The phosphorylation of glucose was measured by the formation of [3H]H2O from [2-3H]glucose in suspensions of freshly isolated rat hepatocytes. Fructose (0.2 mM) stimulated 2-4-fold the rate of phosphorylation of 5 mM glucose although not of 40 mM glucose, thus increasing the apparent affinity of the glucose phosphorylating system. A half-maximal stimulatory effect was observed at about 50 microM fructose. Stimulation was maximal 5 min after addition of the ketose and was stable for at least 40 min, during which period 60% of the fructose was consumed. The effect of fructose was reversible upon removal of the ketose. Sorbitol and tagatose were as potent as fructose in stimulating the phosphorylation of 5 mM glucose. D-Glyceraldehyde also had a stimulatory effect but at tenfold higher concentrations. In contrast, dihydroxyacetone had no significant effect and glycerol inhibited the detritiation of glucose. Oleate did not affect the phosphorylation of glucose, even in the presence of fructose, although it stimulated the formation of ketone bodies severalfold, indicating that it was converted to its acyl-CoA derivative. These results allow the conclusion that fructose stimulates glucokinase in the intact hepatocyte. They also suggest that this effect is mediated through the formation of fructose 1-phosphate, which presumably interacts with a competitive inhibitor of glucokinase other than long-chain acyl-CoAs.

  4. Hepatocytes polyploidization and cell cycle control in liver physiopathology.

    Science.gov (United States)

    Gentric, Géraldine; Desdouets, Chantal; Celton-Morizur, Séverine

    2012-01-01

    Most cells in mammalian tissues usually contain a diploid complement of chromosomes. However, numerous studies have demonstrated a major role of "diploid-polyploid conversion" during physiopathological processes in several tissues. In the liver parenchyma, progressive polyploidization of hepatocytes takes place during postnatal growth. Indeed, at the suckling-weaning transition, cytokinesis failure events induce the genesis of binucleated tetraploid liver cells. Insulin signalling, through regulation of the PI3K/Akt signalling pathway, is essential in the establishment of liver tetraploidization by controlling cytoskeletal organisation and consequently mitosis progression. Liver cell polyploidy is generally considered to indicate terminal differentiation and senescence, and both lead to a progressive loss of cell pluripotency associated to a markedly decreased replication capacity. Although adult liver is a quiescent organ, it retains a capacity to proliferate and to modulate its ploidy in response to various stimuli or aggression (partial hepatectomy, metabolic overload (i.e., high copper and iron hepatic levels), oxidative stress, toxic insult, and chronic hepatitis etc.). Here we review the mechanisms and functional consequences of hepatocytes polyploidization during normal and pathological liver growth.

  5. Hepatocytes Polyploidization and Cell Cycle Control in Liver Physiopathology

    Directory of Open Access Journals (Sweden)

    Géraldine Gentric

    2012-01-01

    Full Text Available Most cells in mammalian tissues usually contain a diploid complement of chromosomes. However, numerous studies have demonstrated a major role of “diploid-polyploid conversion” during physiopathological processes in several tissues. In the liver parenchyma, progressive polyploidization of hepatocytes takes place during postnatal growth. Indeed, at the suckling-weaning transition, cytokinesis failure events induce the genesis of binucleated tetraploid liver cells. Insulin signalling, through regulation of the PI3K/Akt signalling pathway, is essential in the establishment of liver tetraploidization by controlling cytoskeletal organisation and consequently mitosis progression. Liver cell polyploidy is generally considered to indicate terminal differentiation and senescence, and both lead to a progressive loss of cell pluripotency associated to a markedly decreased replication capacity. Although adult liver is a quiescent organ, it retains a capacity to proliferate and to modulate its ploidy in response to various stimuli or aggression (partial hepatectomy, metabolic overload (i.e., high copper and iron hepatic levels, oxidative stress, toxic insult, and chronic hepatitis etc.. Here we review the mechanisms and functional consequences of hepatocytes polyploidization during normal and pathological liver growth.

  6. Metformin protects rat hepatocytes against bile acid-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Titia E Woudenberg-Vrenken

    Full Text Available BACKGROUND: Metformin is used in the treatment of Diabetes Mellitus type II and improves liver function in patients with non-alcoholic fatty liver disease (NAFLD. Metformin activates AMP-activated protein kinase (AMPK, the cellular energy sensor that is sensitive to changes in the AMP/ATP-ratio. AMPK is an inhibitor of mammalian target of rapamycin (mTOR. Both AMPK and mTOR are able to modulate cell death. AIM: To evaluate the effects of metformin on hepatocyte cell death. METHODS: Apoptotic cell death was induced in primary rat hepatocytes using either the bile acid glycochenodeoxycholic acid (GCDCA or TNFα in combination with actinomycin D (actD. AMPK, mTOR and phosphoinositide-3 kinase (PI3K/Akt were inhibited using pharmacological inhibitors. Apoptosis and necrosis were quantified by caspase activation, acridine orange staining and Sytox green staining respectively. RESULTS: Metformin dose-dependently reduces GCDCA-induced apoptosis, even when added 2 hours after GCDCA, without increasing necrotic cell death. Metformin does not protect against TNFα/ActD-induced apoptosis. The protective effect of metformin is dependent on an intact PI3-kinase/Akt pathway, but does not require AMPK/mTOR-signaling. Metformin does not inhibit NF-κB activation. CONCLUSION: Metformin protects against bile acid-induced apoptosis and could be considered in the treatment of chronic liver diseases accompanied by inflammation.

  7. Display technologies for augmented reality

    Science.gov (United States)

    Lee, Byoungho; Lee, Seungjae; Jang, Changwon; Hong, Jong-Young; Li, Gang

    2018-02-01

    With the virtue of rapid progress in optics, sensors, and computer science, we are witnessing that commercial products or prototypes for augmented reality (AR) are penetrating into the consumer markets. AR is spotlighted as expected to provide much more immersive and realistic experience than ordinary displays. However, there are several barriers to be overcome for successful commercialization of AR. Here, we explore challenging and important topics for AR such as image combiners, enhancement of display performance, and focus cue reproduction. Image combiners are essential to integrate virtual images with real-world. Display performance (e.g. field of view and resolution) is important for more immersive experience and focus cue reproduction may mitigate visual fatigue caused by vergence-accommodation conflict. We also demonstrate emerging technologies to overcome these issues: index-matched anisotropic crystal lens (IMACL), retinal projection displays, and 3D display with focus cues. For image combiners, a novel optical element called IMACL provides relatively wide field of view. Retinal projection displays may enhance field of view and resolution of AR displays. Focus cues could be reconstructed via multi-layer displays and holographic displays. Experimental results of our prototypes are explained.

  8. TGFbeta Induces Binucleation/Polyploidization in Hepatocytes through a Src-Dependent Cytokinesis Failure.

    Directory of Open Access Journals (Sweden)

    Marco De Santis Puzzonia

    Full Text Available In all mammals, the adult liver shows binucleated as well as mononucleated polyploid hepatocytes. The hepatic polyploidization starts after birth with an extensive hepatocyte binucleation and generates hepatocytes of several ploidy classes. While the functional significance of hepatocyte polyploidy is becoming clearer, how it is triggered and maintained needs to be clarified. Aim of this study was to identify a major inducer of hepatocyte binucleation/polyploidization and the cellular and molecular mechanisms involved. We found that, among several cytokines analyzed, known to be involved in early liver development and/or mass control, TGFbeta1 was capable to induce, together with the expected morphological changes, binucleation in hepatocytes in culture. Most importantly, the pharmacological inhibition of TGFbeta signaling in healthy mice during weaning, when the physiological binucleation occurs, induced a significant decrease of hepatocyte binucleation rate, without affecting cell proliferation and hepatic index. The TGFbeta-induced hepatocyte binucleation resulted from a cytokinesis failure, as assessed by video microscopy, and is associated with a delocalization of the cytokinesis regulator RhoA-GTPase from the mid-body of dividing cells. The use of specific chemical inhibitors demonstrated that the observed events are Src-dependent. Finally, the restoration of a fully epithelial phenotype by TGFbeta withdrawal gave rise to a cell progeny capable to maintain the polyploid state. In conclusion, we identified TGFbeta as a major inducer of hepatocyte binucleation both in vitro and in vivo, thus ascribing a novel role to this pleiotropic cytokine. The production of binucleated/tetraploid hepatocytes is due to a cytokinesis failure controlled by the molecular axis TGFbeta/Src/RhoA.

  9. TGFbeta Induces Binucleation/Polyploidization in Hepatocytes through a Src-Dependent Cytokinesis Failure.

    Science.gov (United States)

    De Santis Puzzonia, Marco; Cozzolino, Angela Maria; Grassi, Germana; Bisceglia, Francesca; Strippoli, Raffaele; Guarguaglini, Giulia; Citarella, Franca; Sacchetti, Benedetto; Tripodi, Marco; Marchetti, Alessandra; Amicone, Laura

    2016-01-01

    In all mammals, the adult liver shows binucleated as well as mononucleated polyploid hepatocytes. The hepatic polyploidization starts after birth with an extensive hepatocyte binucleation and generates hepatocytes of several ploidy classes. While the functional significance of hepatocyte polyploidy is becoming clearer, how it is triggered and maintained needs to be clarified. Aim of this study was to identify a major inducer of hepatocyte binucleation/polyploidization and the cellular and molecular mechanisms involved. We found that, among several cytokines analyzed, known to be involved in early liver development and/or mass control, TGFbeta1 was capable to induce, together with the expected morphological changes, binucleation in hepatocytes in culture. Most importantly, the pharmacological inhibition of TGFbeta signaling in healthy mice during weaning, when the physiological binucleation occurs, induced a significant decrease of hepatocyte binucleation rate, without affecting cell proliferation and hepatic index. The TGFbeta-induced hepatocyte binucleation resulted from a cytokinesis failure, as assessed by video microscopy, and is associated with a delocalization of the cytokinesis regulator RhoA-GTPase from the mid-body of dividing cells. The use of specific chemical inhibitors demonstrated that the observed events are Src-dependent. Finally, the restoration of a fully epithelial phenotype by TGFbeta withdrawal gave rise to a cell progeny capable to maintain the polyploid state. In conclusion, we identified TGFbeta as a major inducer of hepatocyte binucleation both in vitro and in vivo, thus ascribing a novel role to this pleiotropic cytokine. The production of binucleated/tetraploid hepatocytes is due to a cytokinesis failure controlled by the molecular axis TGFbeta/Src/RhoA.

  10. You Be the Judge: Display.

    Science.gov (United States)

    Koeninger, Jimmy G.

    The instructional package was developed to provide the distributive education teacher-coordinator with visual materials that can be used to supplement existing textbook offerings in the area of display (visual merchandising). Designed for use with 35mm slides of retail store displays, the package allows the student to view the slides of displays…

  11. Displays: Entering a New Dimension

    Science.gov (United States)

    Starkman, Neal

    2007-01-01

    As display technologies prepare to welcome 3-D, the 21st-century classroom will soon bear little resemblance to anything students and teachers have ever seen. In this article, the author presents the latest innovations in the world of digital display technology. These include: (1) Touchlight, an interactive touch screen program that takes a normal…

  12. Software for graphic display systems

    International Nuclear Information System (INIS)

    Karlov, A.A.

    1978-01-01

    In this paper some aspects of graphic display systems are discussed. The design of a display subroutine library is described, with an example, and graphic dialogue software is considered primarily from the point of view of the programmer who uses a high-level language. (Auth.)

  13. Flexible Bistable Cholesteric Reflective Displays

    Science.gov (United States)

    Yang, Deng-Ke

    2006-03-01

    Cholesteric liquid crystals (ChLCs) exhibit two stable states at zero field condition-the reflecting planar state and the nonreflecting focal conic state. ChLCs are an excellent candidate for inexpensive and rugged electronic books and papers. This paper will review the display cell structure,materials and drive schemes for flexible bistable cholesteric (Ch) reflective displays.

  14. Controlled cell morphology and liver-specific function of engineered primary hepatocytes by fibroblast layer cell densities.

    Science.gov (United States)

    Sakai, Yusuke; Koike, Makiko; Kawahara, Daisuke; Hasegawa, Hideko; Murai, Tomomi; Yamanouchi, Kosho; Soyama, Akihiko; Hidaka, Masaaki; Takatsuki, Mitsuhisa; Fujita, Fumihiko; Kuroki, Tamotsu; Eguchi, Susumu

    2018-03-05

    Engineered primary hepatocytes, including co-cultured hepatocyte sheets, are an attractive to basic scientific and clinical researchers because they maintain liver-specific functions, have reconstructed cell polarity, and have high transplantation efficiency. However, co-culture conditions regarding engineered primary hepatocytes were suboptimal in promoting these advantages. Here we report that the hepatocyte morphology and liver-specific function levels are controlled by the normal human diploid fibroblast (TIG-118 cell) layer cell density. Primary rat hepatocytes were plated onto TIG-118 cells, previously plated 3 days before at 1.04, 5.21, and 26.1×10 3  cells/cm 2 . Hepatocytes plated onto lower TIG-118 cell densities expanded better during the early culture period. The hepatocytes gathered as colonies and only exhibited small adhesion areas because of the pushing force from proliferating TIG-118 cells. The smaller areas of each hepatocyte result in the development of bile canaliculi. The highest density of TIG-118 cells downregulated albumin synthesis activity of hepatocytes. The hepatocytes may have undergone apoptosis associated with high TGF-β1 concentration and necrosis due to a lack of oxygen. These occurrences were supported by apoptotic chromatin condensation and high expression of both proteins HIF-1a and HIF-1b. Three types of engineered hepatocyte/fibroblast sheets comprising different TIG-118 cell densities were harvested after 4 days of hepatocyte culture and showed a complete cell sheet format without any holes. Hepatocyte morphology and liver-specific function levels are controlled by TIG-118 cell density, which helps to design better engineered hepatocytes for future applications such as in vitro cell-based assays and transplantable hepatocyte tissues. Copyright © 2018 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  15. INFORMATION DISPLAY: CONSIDERATIONS FOR DESIGNING COMPUTER-BASED DISPLAY SYSTEMS

    International Nuclear Information System (INIS)

    O'HARA, J.M.; PIRUS, D.; BELTRATCCHI, L.

    2004-01-01

    This paper discussed the presentation of information in computer-based control rooms. Issues associated with the typical displays currently in use are discussed. It is concluded that these displays should be augmented with new displays designed to better meet the information needs of plant personnel and to minimize the need for interface management tasks (the activities personnel have to do to access and organize the information they need). Several approaches to information design are discussed, specifically addressing: (1) monitoring, detection, and situation assessment; (2) routine task performance; and (3) teamwork, crew coordination, collaborative work

  16. Flat panel display - Impurity doping technology for flat panel displays

    Energy Technology Data Exchange (ETDEWEB)

    Suzuki, Toshiharu [Advanced Technology Planning, Sumitomo Eaton Nova Corporation, SBS Tower 9F, 10-1, Yoga 4-chome, Setagaya-ku, 158-0097 Tokyo (Japan)]. E-mail: suzuki_tsh@senova.co.jp

    2005-08-01

    Features of the flat panel displays (FPDs) such as liquid crystal display (LCD) and organic light emitting diode (OLED) display, etc. using low temperature poly-Si (LTPS) thin film transistors (TFTs) are briefly reviewed comparing with other FPDs. The requirements for fabricating TFTs used for high performance FPDs and system on glass (SoG) are addressed. This paper focuses on the impurity doping technology, which is one of the key technologies together with crystallization by laser annealing, formation of high quality gate insulator and gate-insulator/poly-Si interface. The issues to be solved in impurity doping technology for state of the art and future TFTs are clarified.

  17. Flat panel display - Impurity doping technology for flat panel displays

    International Nuclear Information System (INIS)

    Suzuki, Toshiharu

    2005-01-01

    Features of the flat panel displays (FPDs) such as liquid crystal display (LCD) and organic light emitting diode (OLED) display, etc. using low temperature poly-Si (LTPS) thin film transistors (TFTs) are briefly reviewed comparing with other FPDs. The requirements for fabricating TFTs used for high performance FPDs and system on glass (SoG) are addressed. This paper focuses on the impurity doping technology, which is one of the key technologies together with crystallization by laser annealing, formation of high quality gate insulator and gate-insulator/poly-Si interface. The issues to be solved in impurity doping technology for state of the art and future TFTs are clarified

  18. Children's Control/Display Stereotypes.

    Science.gov (United States)

    Hoffmann, Errol R; Chan, Alan H S; Tai, Judy P C

    2018-06-01

    Objective The aim of this study was to determine control/display stereotypes for children of a range of ages and development of these stereotypes with age. Background Little is known about control/display stereotypes for children of different ages and the way in which these stereotypes develop with age. This study is part of a program to determine the need to design differentially for these age groups. Method We tested four groups of children with various tasks (age groups 5 to 7, 8 to 10, 11 to 13, 14 to 16), with about 30 in each group. Examples of common tasks were opening a bottle, turning on taps, and allocating numbers to keypads. More complex tasks involved rotating a control to move a display in a requested direction. Results Tasks with which different age groups were familiar showed no effect of age group. Different control/display arrangements generally showed an increase in stereotype strength with age, with dependence on the form of the control/display arrangement. Two-dimensional arrangements, with the control on the same plane as the display, had higher stereotype strength than three-dimensional arrangements for all age groups, suggesting an effect of familiarity with controls and displays with increasing age. Conclusion Children's control/display stereotypes do not differ greatly from those of adults, and hence, design for children older than 5 years of age, for control/display stereotypes, can be the same as that for adult populations. Application When designing devices for children, the relationship between controls and displays can be as for adult populations, for which there are considerable experimental data.

  19. Transplant of Hepatocytes, Undifferentiated Mesenchymal Stem Cells, and In Vitro Hepatocyte-Differentiated Mesenchymal Stem Cells in a Chronic Liver Failure Experimental Model: A Comparative Study.

    Science.gov (United States)

    El Baz, Hanan; Demerdash, Zeinab; Kamel, Manal; Atta, Shimaa; Salah, Faten; Hassan, Salwa; Hammam, Olfat; Khalil, Heba; Meshaal, Safa; Raafat, Inas

    2018-02-01

    Liver transplant is the cornerstone line of treatment for chronic liver diseases; however, the long list of complications and obstacles stand against this operation. Searching for new modalities for treatment of chronic liver illness is a must. In the present research, we aimed to compare the effects of transplant of undifferentiated human mesenchymal stem cells, in vitro differentiated mesenchymal stem cells, and adult hepatocytes in an experimental model of chronic liver failure. Undifferentiated human cord blood mesenchymal stem cells were isolated, pro-pagated, and characterized by morphology, gene expression analysis, and flow cytometry of surface markers and in vitro differentiated into hepatocyte-like cells. Rat hepatocytes were isolated by double perfusion technique. An animal model of chronic liver failure was developed, and undifferentiated human cord blood mesenchymal stem cells, in vitro hepato-genically differentiated mesenchymal stem cells, or freshly isolated rat hepatocytes were transplanted into a CCL4 cirrhotic experimental model. Animals were killed 3 months after transplant, and liver functions and histopathology were assessed. Compared with the cirrhotic control group, the 3 cell-treated groups showed improved alanine aminotransferase, aspartate aminotransferase, albumin, and bilirubin levels, with best results shown in the hepatocyte-treated group. Histopathologic examination of the treated groups showed improved fibrosis, with best results obtained in the undifferentiated mesenchymal stem cell-treated group. Both adult hepatocytes and cord blood mesenchymal stem cells proved to be promising candidates for cell-based therapy in liver regeneration on an experimental level. Improved liver function was evident in the hepatocyte-treated group, and fibrosis control was more evident in the undifferentiated mesenchymal stem cell-treated group.

  20. Circadian rhythms of Per2::Luc in individual primary mouse hepatocytes and cultures.

    Directory of Open Access Journals (Sweden)

    Casey J Guenthner

    Full Text Available BACKGROUND: Hepatocytes, the parenchymal cells of the liver, express core clock genes, such as Period2 and Cryptochrome2, which are involved in the transcriptional/translational feedback loop of the circadian clock. Whether or not the liver is capable of sustaining rhythms independent of a central pacemaker is controversial. Whether and how circadian information may be shared among cells in the liver in order to sustain oscillations is currently unknown. RESULTS: In this study we isolated primary hepatocytes from transgenic Per2(Luc mice and used bioluminescence as a read-out of the state of the circadian clock. Hepatocytes cultured in a collagen gel sandwich configuration exhibited persistent circadian rhythms for several weeks. The amplitude of the rhythms damped, but medium changes consistently reset the phase and amplitude of the cultures. Cry2(-/- Per2(Luc cells oscillated robustly and expressed a longer period. Co-culturing with wildtype cells did not significantly shorten the period, indicating that coupling among hepatocytes is insufficient to synchronize cells with significantly differing periods. However, spatial patterns revealed by cellular imaging of wildtype cultures provided evidence of weak local coupling among the hepatocytes. CONCLUSIONS: Our results with primary hepatocyte cultures demonstrate that cultured hepatocytes are weakly coupled. While this coupling is not sufficient to sustain global synchrony, it does increase local synchrony, which may stabilize the circadian rhythms of peripheral oscillators, such as the liver, against noise in the entraining signals.

  1. Sodium-independent, bicuculline-sensitive [3H]GABA binding to isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Minuk, G.Y.; Bear, C.E.; Sarjeant, E.J.

    1987-01-01

    To determine whether hepatocytes possess specific receptor sites for gamma-aminobutyric acid (GABA), a potent amino acid neurotransmitter, [ 3 H]GABA, was added to sodium-free suspensions of Percoll-purified hepatocytes derived from collagenase-perfused rat livers under various experimental conditions and in the presence or absence of specific GABA receptor agonists (muscimol) and antagonists (bicuculline). The effects of GABA, muscimol, and bicuculline on hepatocyte resting membrane potentials were also determined. Specific binding of [ 3 H]GABA to hepatocytes was a consistent finding. GABA-hepatocyte interactions were reversible and temperature dependent. Muscimol and bicuculline inhibited binding in a dose-dependent manner (IC50, 30 nM and 50 microM, respectively), whereas strychnine (1.0-100 microM), a nonspecific central nervous system stimulant, had no appreciable effect. Both GABA and muscimol (100 microM) caused significant hyperpolarization of hepatocyte resting membrane potential (delta PD 5.4 +/- 3.1 and 22.2 +/- 16.2 mV, respectively, means +/- SD, P less than 0.0005). Bicuculline (100 microM) inhibited the effect of muscimol (P less than 0.05). The results of this study suggest that specific GABA receptor sites exist on the surface of isolated rat hepatocytes. The presence of such sites raises the possibility that, in addition to adrenergic and cholinergic innervation, hepatic function may be influenced by GABA-ergic neurotransmitter mechanisms

  2. Dendritic cells and hepatocytes use distinct pathways to process protective antigen from plasmodium in vivo.

    Directory of Open Access Journals (Sweden)

    Ian A Cockburn

    2011-03-01

    Full Text Available Malaria-protective CD8+ T cells specific for the circumsporozoite (CS protein are primed by dendritic cells (DCs after sporozoite injection by infected mosquitoes. The primed cells then eliminate parasite liver stages after recognizing the CS epitopes presented by hepatocytes. To define the in vivo processing of CS by DCs and hepatocytes, we generated parasites carrying a mutant CS protein containing the H-2K(b epitope SIINFEKL, and evaluated the T cell response using transgenic and mutant mice. We determined that in both DCs and hepatocytes CS epitopes must reach the cytosol and use the TAP transporters to access the ER. Furthermore, we used endosomal mutant (3d and cytochrome c treated mice to address the role of cross-presentation in the priming and effector phases of the T cell response. We determined that in DCs, CS is cross-presented via endosomes while, conversely, in hepatocytes protein must be secreted directly into the cytosol. This suggests that the main targets of protective CD8+ T cells are parasite proteins exported to the hepatocyte cytosol. Surprisingly, however, secretion of the CS protein into hepatocytes was not dependent upon parasite-export (Pexel/VTS motifs in this protein. Together, these results indicate that the presentation of epitopes to CD8+ T cells follows distinct pathways in DCs when the immune response is induced and in hepatocytes during the effector phase.

  3. Human hepatocyte depletion in the presence of HIV-1 infection in dual reconstituted humanized mice

    Science.gov (United States)

    Wang, Weimin; Cheng, Yan; Makarov, Edward; Ganesan, Murali; Gebhart, Catherine L.; Gorantla, Santhi; Osna, Natalia

    2018-01-01

    ABSTRACT Human immunodeficiency virus type 1 (HIV-1) infection impairs liver function, and liver diseases have become a leading cause of morbidity in infected patients. The immunopathology of liver damage caused by HIV-1 remains unclear. We used chimeric mice dually reconstituted with a human immune system and hepatocytes to address the relevance of the model to pathobiology questions related to human hepatocyte survival in the presence of systemic infection. TK-NOG males were transplanted with mismatched human hematopoietic stem/progenitor cells and hepatocytes, human albumin concentration and the presence of human immune cells in blood were monitored for hepatocytes and immune reconstitution, and mice were infected with HIV-1. HIV-1-infected animals showed a decline in human albumin concentration with a significant reduction in percentage of human hepatocytes compared to uninfected mice. The decrease in human albumin levels correlated with a decline in CD4+ cells in the liver and with an increase in HIV-1 viral load. HIV-1 infection elicited proinflammatory response in the immunological milieu of the liver in HIV-infected mice compared to uninfected animals, as determined by upregulation of IL23, CXCL10 and multiple toll-like receptor expression. The inflammatory reaction associated with HIV-1 infection in vivo could contribute to the depletion and dysfunction of hepatocytes. The dual reconstituted TK-NOG mouse model is a feasible platform to investigate hepatocyte-related HIV-1 immunopathogenesis. This article has an associated First Person interview with the first author of the paper. PMID:29361613

  4. Human hepatocyte depletion in the presence of HIV-1 infection in dual reconstituted humanized mice

    Directory of Open Access Journals (Sweden)

    Raghubendra Singh Dagur

    2018-02-01

    Full Text Available Human immunodeficiency virus type 1 (HIV-1 infection impairs liver function, and liver diseases have become a leading cause of morbidity in infected patients. The immunopathology of liver damage caused by HIV-1 remains unclear. We used chimeric mice dually reconstituted with a human immune system and hepatocytes to address the relevance of the model to pathobiology questions related to human hepatocyte survival in the presence of systemic infection. TK-NOG males were transplanted with mismatched human hematopoietic stem/progenitor cells and hepatocytes, human albumin concentration and the presence of human immune cells in blood were monitored for hepatocytes and immune reconstitution, and mice were infected with HIV-1. HIV-1-infected animals showed a decline in human albumin concentration with a significant reduction in percentage of human hepatocytes compared to uninfected mice. The decrease in human albumin levels correlated with a decline in CD4+ cells in the liver and with an increase in HIV-1 viral load. HIV-1 infection elicited proinflammatory response in the immunological milieu of the liver in HIV-infected mice compared to uninfected animals, as determined by upregulation of IL23, CXCL10 and multiple toll-like receptor expression. The inflammatory reaction associated with HIV-1 infection in vivo could contribute to the depletion and dysfunction of hepatocytes. The dual reconstituted TK-NOG mouse model is a feasible platform to investigate hepatocyte-related HIV-1 immunopathogenesis. This article has an associated First Person interview with the first author of the paper.

  5. Cell therapy from bench to bedside: Hepatocytes from fibroblasts - the truth and myth of transdifferentiation.

    Science.gov (United States)

    Sanal, Madhusudana Girija

    2015-06-07

    Hepatocyte transplantation is an alternative to liver transplantation in certain disorders such as inherited liver diseases and liver failure. It is a relatively less complicated surgical procedure, and has the advantage that it can be repeated several times if unsuccessful. Another advantage is that hepatocytes can be isolated from partly damaged livers which are not suitable for liver transplantation. Despite these advantages hepatocyte transplantation is less popular. Important issues are poor engraftment of the transplanted cells and the scarcity of donor hepatocytes. Generation of "hepatocyte like cells"/iHeps from embryonic stem cells (ES) and induced pluripotent stem cells (iPSCs) by directed differentiation is an emerging solution to the latter issue. Direct conversation or trans-differentiation of fibroblasts to "hepatocyte like cells" is another way which is, being explored. However this method has several inherent and technical disadvantages compared to the directed differentiation from ES or iPSC. There are several methods claiming to be "highly efficient" for generating "highly functional" "hepatocyte like cells". Currently different groups are working independently and coming up with differentiation protocols and each group claiming an advantage for their protocol. Directed differentiation protocols need to be designed, compared, analyzed and tweaked systematically and logically than empirically. There is a need for a well-coordinated global initiative comparable to the Human Genome Project to achieve this goal in the near future.

  6. Comparison of para-aminophenol cytotoxicity in rat renal epithelial cells and hepatocytes.

    Science.gov (United States)

    Li, Ying; Bentzley, Catherine M; Tarloff, Joan B

    2005-04-01

    Several chemicals, including para-aminophenol (PAP), produce kidney damage in the absence of hepatic damage. Selective nephrotoxicity may be related to the ability of the kidney to reabsorb filtered water, thereby raising the intraluminal concentration of toxicants and exposing tubular epithelial cells to higher concentrations than would be present in other tissues. The present experiments tested the hypothesis that hepatocytes and renal epithelial cells exposed to equivalent concentrations of PAP would be equally susceptible to toxicity. Hepatocytes and renal epithelial cells were prepared by collagenase digestion of tissues obtained from female Sprague-Dawley rats. Toxicity was monitored using trypan blue exclusion, oxygen consumption and ATP content. We measured the rate of PAP clearance and formation of PAP-glutathione conjugate by HPLC. We found that renal epithelial cells accumulated trypan blue and showed declines in oxygen consumption and ATP content at significantly lower concentrations of PAP and at earlier time points than hepatocytes. The half-life of PAP in hepatocyte incubations was significantly shorter (0.71+/-0.07 h) than in renal epithelial cell incubations (1.33+/-0.23 h), suggesting that renal epithelial cells were exposed to PAP for longer time periods than hepatocytes. Renal epithelial cells formed significantly less glutathione conjugates of PAP (PAP-SG) than did hepatocytes, consistent with less efficient detoxification of reactive PAP intermediates by renal epithelial cells. Finally, hepatocytes contained significant more reduced glutathione (NPSH) than did renal epithelial cells, possibly explaining the enhanced formation of PAP-SG by this cell population. In conclusion, our data indicates that renal epithelial cells are intrinsically more susceptible to PAP cytotoxicity than are hepatocytes. This enhanced cytotoxicity may be due to longer exposure to PAP and/or reduced detoxification of reactive intermediates due to lower concentrations

  7. 3D hepatic cultures simultaneously maintain primary hepatocyte and liver sinusoidal endothelial cell phenotypes.

    Directory of Open Access Journals (Sweden)

    Yeonhee Kim

    Full Text Available Developing in vitro engineered hepatic tissues that exhibit stable phenotype is a major challenge in the field of hepatic tissue engineering. However, the rapid dedifferentiation of hepatic parenchymal (hepatocytes and non-parenchymal (liver sinusoidal endothelial, LSEC cell types when removed from their natural environment in vivo remains a major obstacle. The primary goal of this study was to demonstrate that hepatic cells cultured in layered architectures could preserve or potentially enhance liver-specific behavior of both cell types. Primary rat hepatocytes and rat LSECs (rLSECs were cultured in a layered three-dimensional (3D configuration. The cell layers were separated by a chitosan-hyaluronic acid polyelectrolyte multilayer (PEM, which served to mimic the Space of Disse. Hepatocytes and rLSECs exhibited several key phenotypic characteristics over a twelve day culture period. Immunostaining for the sinusoidal endothelial 1 antibody (SE-1 demonstrated that rLSECs cultured in the 3D hepatic model maintained this unique feature over twelve days. In contrast, rLSECs cultured in monolayers lost their phenotype within three days. The unique stratified structure of the 3D culture resulted in enhanced heterotypic cell-cell interactions, which led to improvements in hepatocyte functions. Albumin production increased three to six fold in the rLSEC-PEM-Hepatocyte cultures. Only rLSEC-PEM-Hepatocyte cultures exhibited increasing CYP1A1/2 and CYP3A activity. Well-defined bile canaliculi were observed only in the rLSEC-PEM-Hepatocyte cultures. Together, these data suggest that rLSEC-PEM-Hepatocyte cultures are highly suitable models to monitor the transformation of toxins in the liver and their transport out of this organ. In summary, these results indicate that the layered rLSEC-PEM-hepatocyte model, which recapitulates key features of hepatic sinusoids, is a potentially powerful medium for obtaining comprehensive knowledge on liver metabolism

  8. Peroxisomal abnormalities in the immortalized human hepatocyte (IHH) cell line.

    Science.gov (United States)

    Klouwer, Femke C C; Koster, Janet; Ferdinandusse, Sacha; Waterham, Hans R

    2017-04-01

    The immortalized human hepatocyte (IHH) cell line is increasingly used for studies related to liver metabolism, including hepatic glucose, lipid, lipoprotein and triglyceride metabolism, and the effect of therapeutic interventions. To determine whether the IHH cell line is a good model to investigate hepatic peroxisomal metabolism, we measured several peroxisomal parameters in IHH cells and, for comparison, HepG2 cells and primary skin fibroblasts. This revealed a marked plasmalogen deficiency and a deficient fatty acid α-oxidation in the IHH cells, due to a defect of PEX7, a cytosolic receptor protein required for peroxisomal import of a subset of peroxisomal proteins. These abnormalities have consequences for the lipid homeostasis of these cells and thus should be taken into account for the interpretation of data previously generated by using this cell line and when considering using this cell line for future research.

  9. Hepatocyte growth factor inhibitor-2 prevents shedding of matritpase

    DEFF Research Database (Denmark)

    Larsen, Brian R; Steffensen, Simon D; Nielsen, Nis V L

    2013-01-01

    Hepatocyte growth factor activator inhibitor-2 (HAI-2) is an inhibitor of many proteases in vitro, including the membrane-bound serine protease, matriptase. Studies of knock-out mice have shown that HAI-2 is essential for placental development only in mice expressing matriptase, suggesting that HAI......-2 is important for regulation of matriptase. Previous studies have shown that recombinant expression of matriptase was unsuccessful unless co-expressed with another HAI, HAI-1. In the present study we show that when human matriptase is recombinantly expressed alone in the canine cell line MDCK......, then human matriptase mRNA can be detected and the human matriptase ectodomain is shed to the media, suggesting that matriptase expressed alone is rapidly transported through the secretory pathway and shed. Whereas matriptase expressed together with HAI-1 or HAI-2 accumulates on the plasma membrane where...

  10. Circular displays: control/display arrangements and stereotype strength with eight different display locations.

    Science.gov (United States)

    Chan, Alan H S; Hoffmann, Errol R

    2015-01-01

    Two experiments are reported that were designed to investigate control/display arrangements having high stereotype strengths when using circular displays. Eight display locations relative to the operator and control were tested with rotational and translational controls situated on different planes according to the Frame of Reference Transformation Tool (FORT) model of Wickens et al. (2010). (Left. No, Right! Development of the Frame of Reference Transformation Tool (FORT), Proceedings of the Human Factors and Ergonomics Society 54th Annual Meeting, 54: 1022-1026). In many cases, there was little effect of display locations, indicating the importance of the Worringham and Beringer (1998. Directional stimulus-response compatibility: a test of three alternative principles. Ergonomics, 41(6), 864-880) Visual Field principle and an extension of this principle for rotary controls (Hoffmann and Chan (2013). The Worringham and Beringer 'visual field' principle for rotary controls. Ergonomics, 56(10), 1620-1624). The initial indicator position (12, 3, 6 and 9 o'clock) had a major effect on control/display stereotype strength for many of the six controls tested. Best display/control arrangements are listed for each of the different control types (rotational and translational) and for the planes on which they are mounted. Data have application where a circular display is used due to limited display panel space and applies to space-craft, robotics operators, hospital equipment and home appliances. Practitioner Summary: Circular displays are often used when there is limited space available on a control panel. Display/control arrangements having high stereotype strength are listed for four initial indicator positions. These arrangements are best for design purposes.

  11. Interaction of propionate and carnitine metabolism in isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Brass, E.P.; Beyerinck, R.A.

    1987-01-01

    Propionate (P) and its metabolic products P-CoA and methylmalonyl-CoA can disrupt normal hepatic metabolism. Carnitine (Cn) has been shown to partially restore cellular function in the presence of P. This effect of Cn may result from removal of propionyl groups as propionylcarnitine (P-Cn). The present study examined the kinetics of P-Cn formation in rat hepatocytes, and the consequence of P-Cn formation on P and Cn metabolism. 14 C-P was converted to CO 2 , glucose and P-Cn in the hepatocyte system. Increasing concentrations of Cn up to 10.0 mM increased P-Cn formation from P without affecting CO 2 or glucose formation. Thus, 10.0 mM Cn increased total P metabolism by 40%. Metabolism of P was associated with a decrease in Cn concentration and an increase in short chain acylcarnitines (SCCn). In the absence of added Cn, 60 min incubation with P decreased Cn from 6.8 to 2.5 μM with a corresponding increase in SCCn. This effect of P to deplete free Cn was not seen to the same degree with butyrate in place of P. Similar increases in the formation of SCCn in the presence of P at the expense of free Cn were seen when the incubation Cn concentration was increased to 50 μM or 150 μM. HPLC methodologies to study specific acylcarnitines demonstrated the accumulation of large amounts of P-Cn in the incubations containing P, accounting for the depletion of free Cn

  12. Glycogen synthase activation by sugars in isolated hepatocytes.

    Science.gov (United States)

    Ciudad, C J; Carabaza, A; Bosch, F; Gòmez I Foix, A M; Guinovart, J J

    1988-07-01

    We have investigated the activation by sugars of glycogen synthase in relation to (i) phosphorylase a activity and (ii) changes in the intracellular concentration of glucose 6-phosphate and adenine nucleotides. All the sugars tested in this work present the common denominator of activating glycogen synthase. On the other hand, phosphorylase a activity is decreased by mannose and glucose, unchanged by galactose and xylitol, and increased by tagatose, glyceraldehyde, and fructose. Dihydroxyacetone exerts a biphasic effect on phosphorylase. These findings provide additional evidence proving that glycogen synthase can be activated regardless of the levels of phosphorylase a, clearly establishing that a nonsequential mechanism for the activation of glycogen synthase occurs in liver cells. The glycogen synthase activation state is related to the concentrations of glucose 6-phosphate and adenine nucleotides. In this respect, tagatose, glyceraldehyde, and fructose deplete ATP and increase AMP contents, whereas glucose, mannose, galactose, xylitol, and dihydroxyacetone do not alter the concentration of these nucleotides. In addition, all these sugars, except glyceraldehyde, increase the intracellular content of glucose 6-phosphate. The activation of glycogen synthase by sugars is reflected in decreases on both kinetic constants of the enzyme, M0.5 (for glucose 6-phosphate) and S0.5 (for UDP-glucose). We propose that hepatocyte glycogen synthase is activated by monosaccharides by a mechanism triggered by changes in glucose 6-phosphate and adenine nucleotide concentrations which have been described to modify glycogen synthase phosphatase activity. This mechanism represents a metabolite control of the sugar-induced activation of hepatocyte glycogen synthase.

  13. Color speckle in laser displays

    Science.gov (United States)

    Kuroda, Kazuo

    2015-07-01

    At the beginning of this century, lighting technology has been shifted from discharge lamps, fluorescent lamps and electric bulbs to solid-state lighting. Current solid-state lighting is based on the light emitting diodes (LED) technology, but the laser lighting technology is developing rapidly, such as, laser cinema projectors, laser TVs, laser head-up displays, laser head mounted displays, and laser headlamps for motor vehicles. One of the main issues of laser displays is the reduction of speckle noise1). For the monochromatic laser light, speckle is random interference pattern on the image plane (retina for human observer). For laser displays, RGB (red-green-blue) lasers form speckle patterns independently, which results in random distribution of chromaticity, called color speckle2).

  14. Integrated Display & Environmental Awareness System

    Data.gov (United States)

    National Aeronautics and Space Administration — The goal of this project is the development of a head mounted display for use in operations here on Earth and in Space. The technology would provide various means of...

  15. Performance of NCAP projection displays

    Science.gov (United States)

    Jones, Philip J.; Tomita, Akira; Wartenberg, Mark

    1991-08-01

    Prototypes of projection displays based on dispersions of liquid crystal in polymer matrices are beginning to appear. The principle of operation depends on electrically switchable light scattering. They are potentially much brighter than current cathode ray tube (CRT) or twisted nematic liquid crystal (TN LC) cell based displays. Comparisons of efficacy and efficiency show this. The contrast and brightness of such displays depend on a combination of the f- number of the projection system and the scattering characteristics of the light valve. Simplified equations can be derived to show these effects. The degree of scattering of current NCAP formulations is sufficient to produce good contrast projection displays, at convenient voltages, that are around three times brighter than TN LC projectors because of the lack of polarizers in the former.

  16. Interactive editing program using display

    International Nuclear Information System (INIS)

    Lang, I.; Ehsenski, J.; Namsraj, Yu.; Fefilov, B.V.

    1976-01-01

    A general description is given as well as principal functions are considered of 'DOSE' interactive editor program with a display involved. The program has been elaborated for TRA/1-1001 computer. This program enables one to edit and correct texts in algorithmical languages on a raster display screen as well as to provide perforated tapes for their further usage. 'DOSE' program is regarded as a basic program system for a set of TRA/1 and MINSK-32 computers

  17. Long-term exposure to abnormal glucose levels alters drug metabolism pathways and insulin sensitivity in primary human hepatocytes

    Science.gov (United States)

    Davidson, Matthew D.; Ballinger, Kimberly R.; Khetani, Salman R.

    2016-06-01

    Hyperglycemia in type 2 diabetes mellitus has been linked to non-alcoholic fatty liver disease, which can progress to inflammation, fibrosis/cirrhosis, and hepatocellular carcinoma. Understanding how chronic hyperglycemia affects primary human hepatocytes (PHHs) can facilitate the development of therapeutics for these diseases. Conversely, elucidating the effects of hypoglycemia on PHHs may provide insights into how the liver adapts to fasting, adverse diabetes drug reactions, and cancer. In contrast to declining PHH monocultures, micropatterned co-cultures (MPCCs) of PHHs and 3T3-J2 murine embryonic fibroblasts maintain insulin-sensitive glucose metabolism for several weeks. Here, we exposed MPCCs to hypo-, normo- and hyperglycemic culture media for ~3 weeks. While albumin and urea secretion were not affected by glucose level, hypoglycemic MPCCs upregulated CYP3A4 enzyme activity as compared to other glycemic states. In contrast, hyperglycemic MPCCs displayed significant hepatic lipid accumulation in the presence of insulin, while also showing decreased sensitivity to insulin-mediated inhibition of glucose output relative to a normoglycemic control. In conclusion, we show for the first time that PHHs exposed to hypo- and hyperglycemia can remain highly functional, but display increased CYP3A4 activity and selective insulin resistance, respectively. In the future, MPCCs under glycemic states can aid in novel drug discovery and mechanistic investigations.

  18. Impaired mitochondrial functions contribute to 3-bromopyruvate toxicity in primary rat and mouse hepatocytes

    Czech Academy of Sciences Publication Activity Database

    Sobotka, O.; Endlicher, R.; Drahota, Zdeněk; Kučera, O.; Rychtrmoc, D.; Raad, M.; Hakeem, K.; Červinková, Z.

    2016-01-01

    Roč. 48, č. 4 (2016), s. 363-373 ISSN 0145-479X Institutional support: RVO:67985823 Keywords : 3-bromopyruvate * toxicity * liver * hepatocyte * mitochondria Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.576, year: 2016

  19. SELENIUM MODIFIES THE METABOLISM AND TOXICITY OF ARSENIC IN PRIMARY RAT HEPATOCYTES

    Science.gov (United States)

    ABSTRACTSelenium Modifies the Metabolism and Toxicity of Arsenic in Primary Rat Hepatocytes. Miroslav Styblo, David J. Thomas (2000) Toxicol. Appl. Pharmacol. Arsenic and selenium are metalloids with similar chemical properties and metabolic fates. Inorganic arsenic (iAs...

  20. Acidosis-induced downregulation of hepatocyte mitochondrial aquaporin-8 and ureagenesis from ammonia.

    Science.gov (United States)

    Molinas, Sara M; Soria, Leandro R; Marrone, Julieta; Danielli, Mauro; Trumper, Laura; Marinelli, Raúl A

    2015-08-01

    It has been proposed that, during metabolic acidosis, the liver downregulates mitochondrial ammonia detoxification via ureagenesis, a bicarbonate-consuming process. Since we previously demonstrated that hepatocyte mitochondrial aquaporin-8 channels (mtAQP8) facilitate the uptake of ammonia and its metabolism into urea, we studied whether mtAQP8 is involved in the liver adaptive response to acidosis. Primary cultured rat hepatocytes were adapted to acidosis by exposing them to culture medium at pH 7.0 for 40 h. Control cells were exposed to pH 7.4. Hepatocytes exposed to acid medium showed a decrease in mtAQP8 protein expression (-30%, p ammonia was assessed by incubating the cells with (15)N-labeled ammonia and measuring (15)N-labeled urea synthesis by nuclear magnetic resonance. Reduced ureagenesis was found in acidified hepatocytes (-31%, p ammonia in response to acidosis.

  1. Hepatocyte produced matrix metalloproteinases are regulated by CD147 in liver fibrogenesis.

    Science.gov (United States)

    Calabro, Sarah R; Maczurek, Annette E; Morgan, Alison J; Tu, Thomas; Wen, Victoria W; Yee, Christine; Mridha, Auvro; Lee, Maggie; d'Avigdor, William; Locarnini, Stephen A; McCaughan, Geoffrey W; Warner, Fiona J; McLennan, Susan V; Shackel, Nicholas A

    2014-01-01

    The classical paradigm of liver injury asserts that hepatic stellate cells (HSC) produce, remodel and turnover the abnormal extracellular matrix (ECM) of fibrosis via matrix metalloproteinases (MMPs). In extrahepatic tissues MMP production is regulated by a number of mechanisms including expression of the glycoprotein CD147. Previously, we have shown that CD147 is expressed on hepatocytes but not within the fibrotic septa in cirrhosis [1]. Therefore, we investigated if hepatocytes produce MMPs, regulated by CD147, which are capable of remodelling fibrotic ECM independent of the HSC. Non-diseased, fibrotic and cirrhotic livers were examined for MMP activity and markers of fibrosis in humans and mice. CD147 expression and MMP activity were co-localised by in-situ zymography. The role of CD147 was studied in-vitro with siRNA to CD147 in hepatocytes and in-vivo in mice with CCl4 induced liver injury using ãCD147 antibody intervention. In liver fibrosis in both human and mouse tissue MMP expression and activity (MMP-2, -9, -13 and -14) increased with progressive injury and localised to hepatocytes. Additionally, as expected, MMPs were abundantly expressed by activated HSC. Further, with progressive fibrosis there was expression of CD147, which localised to hepatocytes but not to HSC. Functionally significant in-vitro regulation of hepatocyte MMP production by CD147 was demonstrated using siRNA to CD147 that decreased hepatocyte MMP-2 and -9 expression/activity. Further, in-vivo α-CD147 antibody intervention decreased liver MMP-2, -9, -13, -14, TGF-β and α-SMA expression in CCl4 treated mice compared to controls. We have shown that hepatocytes produce active MMPs and that the glycoprotein CD147 regulates hepatocyte MMP expression. Targeting CD147 regulates hepatocyte MMP production both in-vitro and in-vivo, with the net result being reduced fibrotic matrix turnover in-vivo. Therefore, CD147 regulation of hepatocyte MMP is a novel pathway that could be targeted by

  2. Hepatocyte produced matrix metalloproteinases are regulated by CD147 in liver fibrogenesis.

    Directory of Open Access Journals (Sweden)

    Sarah R Calabro

    Full Text Available The classical paradigm of liver injury asserts that hepatic stellate cells (HSC produce, remodel and turnover the abnormal extracellular matrix (ECM of fibrosis via matrix metalloproteinases (MMPs. In extrahepatic tissues MMP production is regulated by a number of mechanisms including expression of the glycoprotein CD147. Previously, we have shown that CD147 is expressed on hepatocytes but not within the fibrotic septa in cirrhosis [1]. Therefore, we investigated if hepatocytes produce MMPs, regulated by CD147, which are capable of remodelling fibrotic ECM independent of the HSC.Non-diseased, fibrotic and cirrhotic livers were examined for MMP activity and markers of fibrosis in humans and mice. CD147 expression and MMP activity were co-localised by in-situ zymography. The role of CD147 was studied in-vitro with siRNA to CD147 in hepatocytes and in-vivo in mice with CCl4 induced liver injury using ãCD147 antibody intervention.In liver fibrosis in both human and mouse tissue MMP expression and activity (MMP-2, -9, -13 and -14 increased with progressive injury and localised to hepatocytes. Additionally, as expected, MMPs were abundantly expressed by activated HSC. Further, with progressive fibrosis there was expression of CD147, which localised to hepatocytes but not to HSC. Functionally significant in-vitro regulation of hepatocyte MMP production by CD147 was demonstrated using siRNA to CD147 that decreased hepatocyte MMP-2 and -9 expression/activity. Further, in-vivo α-CD147 antibody intervention decreased liver MMP-2, -9, -13, -14, TGF-β and α-SMA expression in CCl4 treated mice compared to controls.We have shown that hepatocytes produce active MMPs and that the glycoprotein CD147 regulates hepatocyte MMP expression. Targeting CD147 regulates hepatocyte MMP production both in-vitro and in-vivo, with the net result being reduced fibrotic matrix turnover in-vivo. Therefore, CD147 regulation of hepatocyte MMP is a novel pathway that could be

  3. Characteristics of inositol trisphosphate mediated Ca2+ release from permeabilized hepatocytes

    International Nuclear Information System (INIS)

    Joseph, S.K.; Williamson, J.R.

    1986-01-01

    Ca 2+ release triggered by inositol trisphosphate (IP 3 ) has been measured in saponin-permeabilized hepatocytes with 45 Ca 2+ or Quin 2. The initial rate of Ca 2+ release was not markedly affected by the incubation temperature (175 +/- 40 pmol/s/mg at 30 0 C versus 133 +/- 24 pmol/s/mg at 4 0 C). This result is consistent with the membrane translocation of Ca 2+ occurring through an ion-channel rather than an ion-carrier. The amount of Ca 2+ released by IP 3 was not affected by pH (6.5-8.0) or by compounds that inhibit voltage-gated Ca 2+ channels. La 3+ (100 μM) markedly inhibits the effect of 1 μM IP 3 . The possibility that La 3+ chelates IP 3 cannot be excluded since the effect of La 3+ can be overcome by increasing the IP 3 concentration. IP 3 -mediated Ca 2+ release displays a requirement for a permeant cation in the incubation medium. Optimal release is observed with K + gluconate. Other monovalent cations, with the exception of Li + , can substitute for K + . Permeant anions, at concentrations above 40 mM, inhibit Ca 2+ release produced by IP 3 . Cl - , Br - , I - , and SO 4 2- were equally effective. Ca 2+ release was not inhibited by DIDS or Furosemide. 85 Sr 2+ and 54 Mn 2+ fluxes were also stimulated by IP 3 . These results suggest that IP 3 acts to gate a divalent cation channel. The translocation of positive charge through this channel is balanced by ancillary movements of monovalent cations and anions across the reticular membrane

  4. Hypoxia-inducible factor-dependent production of profibrotic mediators by hypoxic hepatocytes.

    Science.gov (United States)

    Copple, Bryan L; Bustamante, Juan J; Welch, Timothy P; Kim, Nam Deuk; Moon, Jeon-Ok

    2009-08-01

    During the development of liver fibrosis, mediators are produced that stimulate cells in the liver to differentiate into myofibroblasts and to produce collagen. Recent studies demonstrated that the transcription factor, hypoxia-inducible factor-1alpha (HIF-1alpha), is critical for upregulation of profibrotic mediators, such as platelet-derived growth factor-A (PDGF-A), PDGF-B and plasminogen activator inhibitor-1 (PAI-1) in the liver, during the development of fibrosis. What remains unknown is the cell type-specific regulation of these genes by HIF-1alpha in liver cell types. Accordingly, the hypothesis was tested that HIF-1alpha is activated in hypoxic hepatocytes and regulates the production of profibrotic mediators by these cells. In this study, hepatocytes were isolated from the livers of control and HIF-1alpha- or HIF-1beta-deficient mice and exposed to hypoxia. Exposure of primary mouse hepatocytes to 1% oxygen stimulated nuclear accumulation of HIF-1alpha and upregulated PAI-1, vascular endothelial cell growth factor and the vasoactive peptides adrenomedullin-1 (ADM-1) and ADM-2. In contrast, the levels of PDGF-A and PDGF-B mRNAs were unaffected in these cells by hypoxia. Exposure of HIF-1alpha-deficient hepatocytes to 1% oxygen only partially prevented upregulation of these genes, suggesting that other hypoxia-regulated transcription factors, such as HIF-2alpha, may also regulate these genes. In support of this, HIF-2alpha was activated in hypoxic hepatocytes, and exposure of HIF-1beta-deficient hepatocytes to 1% oxygen completely prevented upregulation of PAI-1, vascular endothelial cell growth factor and ADM-1, suggesting that HIF-2alpha may also contribute to upregulation of these genes in hypoxic hepatocytes. Collectively, our results suggest that HIFs may be important regulators of profibrotic and vasoactive mediators by hypoxic hepatocytes.

  5. Bile acid-induced necrosis in primary human hepatocytes and in patients with obstructive cholestasis

    Energy Technology Data Exchange (ETDEWEB)

    Woolbright, Benjamin L.; Dorko, Kenneth [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Antoine, Daniel J.; Clarke, Joanna I. [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Gholami, Parviz [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Li, Feng [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Kumer, Sean C.; Schmitt, Timothy M.; Forster, Jameson [Department of Surgery, University of Kansas Medical Center, Kansas City, KS (United States); Fan, Fang [Department of Pathology, University of Kansas Medical Center, Kansas City, KS (United States); Jenkins, Rosalind E.; Park, B. Kevin [MRC Centre for Drug Safety Science, Department of Molecular and Clinical Pharmacology, Institute of Translational Medicine, University of Liverpool, Liverpool (United Kingdom); Hagenbuch, Bruno [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States); Olyaee, Mojtaba [Department of Internal Medicine, University of Kansas Medical Center, Kansas City, KS (United States); Jaeschke, Hartmut, E-mail: hjaeschke@kumc.edu [Department of Pharmacology, Toxicology & Therapeutics, University of Kansas Medical Center, Kansas City, KS (United States)

    2015-03-15

    Accumulation of bile acids is a major mediator of cholestatic liver injury. Recent studies indicate bile acid composition between humans and rodents is dramatically different, as humans have a higher percent of glycine conjugated bile acids and increased chenodeoxycholate content, which increases the hydrophobicity index of bile acids. This increase may lead to direct toxicity that kills hepatocytes, and promotes inflammation. To address this issue, this study assessed how pathophysiological concentrations of bile acids measured in cholestatic patients affected primary human hepatocytes. Individual bile acid levels were determined in serum and bile by UPLC/QTOFMS in patients with extrahepatic cholestasis with, or without, concurrent increases in serum transaminases. Bile acid levels increased in serum of patients with liver injury, while biliary levels decreased, implicating infarction of the biliary tracts. To assess bile acid-induced toxicity in man, primary human hepatocytes were treated with relevant concentrations, derived from patient data, of the model bile acid glycochenodeoxycholic acid (GCDC). Treatment with GCDC resulted in necrosis with no increase in apoptotic parameters. This was recapitulated by treatment with biliary bile acid concentrations, but not serum concentrations. Marked elevations in serum full-length cytokeratin-18, high mobility group box 1 protein (HMGB1), and acetylated HMGB1 confirmed inflammatory necrosis in injured patients; only modest elevations in caspase-cleaved cytokeratin-18 were observed. These data suggest human hepatocytes are more resistant to human-relevant bile acids than rodent hepatocytes, and die through necrosis when exposed to bile acids. These mechanisms of cholestasis in humans are fundamentally different to mechanisms observed in rodent models. - Highlights: • Cholestatic liver injury is due to cytoplasmic bile acid accumulation in hepatocytes. • Primary human hepatocytes are resistant to BA-induced injury

  6. Acrolein cytotoxicity in hepatocytes involves endoplasmic reticulum stress, mitochondrial dysfunction and oxidative stress

    OpenAIRE

    Mohammad, Mohammad K; Avila, Diana; Zhang, Jingwen; Barve, Shirish; Arteel, Gavin; McClain, Craig; Joshi-Barve, Swati

    2012-01-01

    Acrolein is a common environmental, food and water pollutant and a major component of cigarette smoke. Also, it is produced endogenously via lipid peroxidation and cellular metabolism of certain amino acids and drugs. Acrolein is cytotoxic to many cell types including hepatocytes; however the mechanisms are not fully understood. We examined the molecular mechanisms underlying acrolein hepatotoxicity in primary human hepatocytes and hepatoma cells. Acrolein, at pathophysiological concentration...

  7. Role of CYP2B in Phenobarbital-Induced Hepatocyte Proliferation in Mice.

    Science.gov (United States)

    Li, Lei; Bao, Xiaochen; Zhang, Qing-Yu; Negishi, Masahiko; Ding, Xinxin

    2017-08-01

    Phenobarbital (PB) promotes liver tumorigenesis in rodents, in part through activation of the constitutive androstane receptor (CAR) and the consequent changes in hepatic gene expression and increases in hepatocyte proliferation. A typical effect of CAR activation by PB is a marked induction of Cyp2b10 expression in the liver; the latter has been suspected to be vital for PB-induced hepatocellular proliferation. This hypothesis was tested here by using a Cyp2a(4/5)bgs -null (null) mouse model in which all Cyp2b genes are deleted. Adult male and female wild-type (WT) and null mice were treated intraperitoneally with PB at 50 mg/kg once daily for 5 successive days and tested on day 6. The liver-to-body weight ratio, an indicator of liver hypertrophy, was increased by 47% in male WT mice, but by only 22% in male Cyp2a(4/5)bgs -null mice, by the PB treatment. The fractions of bromodeoxyuridine-positive hepatocyte nuclei, assessed as a measure of the rate of hepatocyte proliferation, were also significantly lower in PB-treated male null mice compared with PB-treated male WT mice. However, whereas few proliferating hepatocytes were detected in saline-treated mice, many proliferating hepatocytes were still detected in PB-treated male null mice. In contrast, female WT mice were much less sensitive than male WT mice to PB-induced hepatocyte proliferation, and PB-treated female WT and PB-treated female null mice did not show significant difference in rates of hepatocyte proliferation. These results indicate that CYP2B induction plays a significant, but partial, role in PB-induced hepatocyte proliferation in male mice. U.S. Government work not protected by U.S. copyright.

  8. Optimization of the isolation and cultivation of Cyprinus carpio primary hepatocytes

    OpenAIRE

    Yanhong, Fan; Chenghua, He; Guofang, Liu; Haibin, Zhang

    2008-01-01

    The aquatic environment is affected by numerous chemical contaminants. There is an increasing need to identify these chemicals and to evaluate their potential toxicity towards aquatic life. In this research we optimized techniques for primary cell culture of Cyprinus carpio hepatocytes as one adjunct model for ecotoxicological evaluation of the potential hazards of xenobiotics in the aquatic environment. In this study, Cyprinus carpio hepatocytes were isolated by mechanical separation, two-st...

  9. Subtoxic Alterations in Hepatocyte-Derived Exosomes: An Early Step in Drug-Induced Liver Injury?

    Science.gov (United States)

    Holman, Natalie S; Mosedale, Merrie; Wolf, Kristina K; LeCluyse, Edward L; Watkins, Paul B

    2016-06-01

    Drug-induced liver injury (DILI) is a significant clinical and economic problem in the United States, yet the mechanisms that underlie DILI remain poorly understood. Recent evidence suggests that signaling molecules released by stressed hepatocytes can trigger immune responses that may be common across DILI mechanisms. Extracellular vesicles released by hepatocytes, principally hepatocyte-derived exosomes (HDEs), may constitute one such signal. To examine HDE alterations as a function of drug-induced stress, this work utilized prototypical hepatotoxicant acetaminophen (APAP) in male Sprague-Dawley (SD) rats, SD rat hepatocytes, and primary human hepatocytes. HDE were isolated using ExoQuick precipitation reagent and analyzed by quantification of the liver-specific RNAs albumin and microRNA-122 (miR-122). In vivo, significant elevations in circulating exosomal albumin mRNA were observed at subtoxic APAP exposures. Significant increases in exosomal albumin mRNA were also observed in primary rat hepatocytes at subtoxic APAP concentrations. In primary human hepatocytes, APAP elicited increases in both exosomal albumin mRNA and exosomal miR-122 without overt cytotoxicity. However, the number of HDE produced in vitro in response to APAP did not increase with exosomal RNA quantity. We conclude that significant drug-induced alterations in the liver-specific RNA content of HDE occur at subtoxic APAP exposures in vivo and in vitro, and that these changes appear to reflect selective packaging rather than changes in exosome number. The current findings demonstrate that translationally relevant HDE alterations occur in the absence of overt hepatocellular toxicity, and support the hypothesis that HDE released by stressed hepatocytes may mediate early immune responses in DILI. © The Author 2016. Published by Oxford University Press on behalf of the Society of Toxicology. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  10. On-line data display

    Science.gov (United States)

    Lang, Sherman Y. T.; Brooks, Martin; Gauthier, Marc; Wein, Marceli

    1993-05-01

    A data display system for embedded realtime systems has been developed for use as an operator's user interface and debugging tool. The motivation for development of the On-Line Data Display (ODD) have come from several sources. In particular the design reflects the needs of researchers developing an experimental mobile robot within our laboratory. A proliferation of specialized user interfaces revealed a need for a flexible communications and graphical data display system. At the same time the system had to be readily extensible for arbitrary graphical display formats which would be required for data visualization needs of the researchers. The system defines a communication protocol transmitting 'datagrams' between tasks executing on the realtime system and virtual devices displaying the data in a meaningful way on a graphical workstation. The communication protocol multiplexes logical channels on a single data stream. The current implementation consists of a server for the Harmony realtime operating system and an application written for the Macintosh computer. Flexibility requirements resulted in a highly modular server design, and a layered modular object- oriented design for the Macintosh part of the system. Users assign data types to specific channels at run time. Then devices are instantiated by the user and connected to channels to receive datagrams. The current suite of device types do not provide enough functionality for most users' specialized needs. Instead the system design allows the creation of new device types with modest programming effort. The protocol, design and use of the system are discussed.

  11. Effects of Cytochrome P 450 Inhibitors on Itraconazole and Fluconazole Induced Cytotoxicity in Hepatocytes

    International Nuclear Information System (INIS)

    Somchit, N.; Ngee, C.S.; Yaakob, A.; Ahmad, Z.; Zakaria, Z.A.

    2009-01-01

    Itraconazole and fluconazole have been reported to induce hepatotoxicity in patients. The present study was designed to investigate the role of cytochrome P450 inhibitors, SKF 525A, and curcumin pretreatment on the cytotoxicity of antifungal drugs fluconazole and itraconazole. For 3 consecutive days, female rats were administered daily SKF 525A or curcumin (5 and 25?mg/kg). Control rats received an equivalent amount of dosed vehicle. The animals were anaesthetised 24 hours after receiving the last dose for liver perfusion. Hepatocytes were then exposed to various concentrations of antifungal drugs. In vitro incubation of hepatocytes with itraconazole revealed significantly lower viability when compared to fluconazole as assessed by lactate dehydrogenase, aspartate aminotransferase and alanine aminotransferase activities. The cytotoxicity of itraconazole was enhanced when incubated with hepatocytes pretreated with SKF 525A. SKF 525A had no effects on the cytotoxicity of fluconazole. Curcumin failed to either increase or decrease the cytotoxicity of both antifungal drugs. ATP levels also showed significant decrease in both itraconazole and fluconazole incubated hepatocytes. However, SKF 525A pretreated hepatocytes had significantly lower ATP levels after itraconazole incubations. Collectively, these results confirm the involvement of cytochrome P450 in the cytoprotection in itraconazole induced hepatocyte toxicity. Differences of the effects of SKF 525A on the cytotoxicity induced by itraconazole and fluconazole may be due to the differences on the metabolism of each antifungal drug in vivo.

  12. YAP Inhibition Restores Hepatocyte Differentiation in Advanced HCC, Leading to Tumor Regression

    Directory of Open Access Journals (Sweden)

    Julien Fitamant

    2015-03-01

    Full Text Available Defective Hippo/YAP signaling in the liver results in tissue overgrowth and development of hepatocellular carcinoma (HCC. Here, we uncover mechanisms of YAP-mediated hepatocyte reprogramming and HCC pathogenesis. YAP functions as a rheostat in maintaining metabolic specialization, differentiation, and quiescence within the hepatocyte compartment. Increased or decreased YAP activity reprograms subsets of hepatocytes to different fates associated with deregulation of the HNF4A, CTNNB1, and E2F transcriptional programs that control hepatocyte quiescence and differentiation. Importantly, treatment with small interfering RNA-lipid nanoparticles (siRNA-LNPs targeting YAP restores hepatocyte differentiation and causes pronounced tumor regression in a genetically engineered mouse HCC model. Furthermore, YAP targets are enriched in an aggressive human HCC subtype characterized by a proliferative signature and absence of CTNNB1 mutations. Thus, our work reveals Hippo signaling as a key regulator of the positional identity of hepatocytes, supports targeting of YAP using siRNA-LNPs as a paradigm of differentiation-based therapy, and identifies an HCC subtype that is potentially responsive to this approach.

  13. Hepatocyte transplantation and advancements in alternative cell sources for liver-based regenerative medicine.

    Science.gov (United States)

    Lee, Charlotte A; Sinha, Siddharth; Fitzpatrick, Emer; Dhawan, Anil

    2018-06-01

    Human hepatocyte transplantation has been actively perused as an alternative to liver replacement for acute liver failure and liver-based metabolic defects. Current challenges in this field include a limited cell source, reduced cell viability following cryopreservation and poor engraftment of cells into the recipient liver with consequent limited life span. As a result, alternative stem cell sources such as pluripotent stem cells, fibroblasts, hepatic progenitor cells, amniotic epithelial cells and mesenchymal stem/stromal cells (MSCs) can be used to generate induced hepatocyte like cells (HLC) with each technique exhibiting advantages and disadvantages. HLCs may have comparable function to primary human hepatocytes and could offer patient-specific treatment. However, long-term functionality of transplanted HLCs and the potential oncogenic risks of using stem cells have yet to be established. The immunomodulatory effects of MSCs are promising, and multiple clinical trials are investigating their effect in cirrhosis and acute liver failure. Here, we review the current status of hepatocyte transplantation, alternative cell sources to primary human hepatocytes and their potential in liver regeneration. We also describe recent clinical trials using hepatocytes derived from stem cells and their role in improving the phenotype of several liver diseases.

  14. To 'display' or not to 'display'- that is the peptide

    CSIR Research Space (South Africa)

    Crampton, Michael C

    2008-11-01

    Full Text Available eukaryotic and prokaryotic systems but has mainly focused around phages (Etz et al, 2001), yeast (Kondo and Ueda, 2004) and bacteria (Lee et al 2003). The central variable domain of the FliC protein is dispensable and can be used for the insertion and display...

  15. Chronic Ethanol Consumption in Mice Alters Hepatocyte Lipid Droplet Properties

    Science.gov (United States)

    Orlicky, David J.; Roede, James R.; Bales, Elise; Greenwood, Carrie; Greenberg, Andrew; Petersen, Dennis; McManaman, James L.

    2014-01-01

    Background Hepatosteatosis is a common pathological feature of impaired hepatic metabolism following chronic alcohol consumption. Although often benign and reversible, it is widely believed that steatosis is a risk factor for development of advanced liver pathologies, including steatohepatitis and fibrosis. The hepatocyte alterations accompanying the initiation of steatosis are not yet clearly defined. Methods Induction of hepatosteatosis by chronic ethanol consumption was investigated using the Lieber-DeCarli (LD) high fat diet model. Effects were assessed by immunohistochemistry and blood and tissue enzymatic assays. Cell culture models were employed for mechanistic studies. Results Pair feeding mice ethanol (LD-Et) or isocaloric control (LD-Co) diets for 6 weeks progressively increased hepatocyte triglyceride accumulation in morphological, biochemical, and zonally distinct cytoplasmic lipid droplets (CLD). The LD-Et diet induced zone 2-specific triglyceride accumulation in large CLD coated with perilipin, adipophilin (ADPH), and TIP47. In LD-Co- fed mice, CLD were significantly smaller than those in LD-Et-fed mice and lacked perilipin. A direct role of perilipin in formation of large CLD was further suggested by cell culture studies showing that perilipin-coated CLD were significantly larger than those coated with ADPH or TIP47. LD-Co- and LD-Et-fed animals also differed in hepatic metabolic stress responses. In LD-Et but not LD-Co-fed mice, inductions were observed in the following: microsomal ethanol-oxidizing system [cytochrome P-4502E1 (CYP2E1)], hypoxia response pathway (hypoxia-inducible factor 1 alpha, HIF1α), endoplasmic reticulum stress pathway (calreticulin), and synthesis of lipid peroxidation products [4-hydroxynonenal (4-HNE)]. CYP2E1 and HIF1 α immunostaining localized to zone 3 and did not correlate with accumulation of large CLD. In contrast, calreticulin and 4-HNE immunostaining closely correlated with large CLD accumulation. Importantly, 4

  16. IMDISP - INTERACTIVE IMAGE DISPLAY PROGRAM

    Science.gov (United States)

    Martin, M. D.

    1994-01-01

    The Interactive Image Display Program (IMDISP) is an interactive image display utility for the IBM Personal Computer (PC, XT and AT) and compatibles. Until recently, efforts to utilize small computer systems for display and analysis of scientific data have been hampered by the lack of sufficient data storage capacity to accomodate large image arrays. Most planetary images, for example, require nearly a megabyte of storage. The recent development of the "CDROM" (Compact Disk Read-Only Memory) storage technology makes possible the storage of up to 680 megabytes of data on a single 4.72-inch disk. IMDISP was developed for use with the CDROM storage system which is currently being evaluated by the Planetary Data System. The latest disks to be produced by the Planetary Data System are a set of three disks containing all of the images of Uranus acquired by the Voyager spacecraft. The images are in both compressed and uncompressed format. IMDISP can read the uncompressed images directly, but special software is provided to decompress the compressed images, which can not be processed directly. IMDISP can also display images stored on floppy or hard disks. A digital image is a picture converted to numerical form so that it can be stored and used in a computer. The image is divided into a matrix of small regions called picture elements, or pixels. The rows and columns of pixels are called "lines" and "samples", respectively. Each pixel has a numerical value, or DN (data number) value, quantifying the darkness or brightness of the image at that spot. In total, each pixel has an address (line number, sample number) and a DN value, which is all that the computer needs for processing. DISPLAY commands allow the IMDISP user to display all or part of an image at various positions on the display screen. The user may also zoom in and out from a point on the image defined by the cursor, and may pan around the image. To enable more or all of the original image to be displayed on the

  17. Visual Attention to Radar Displays

    Science.gov (United States)

    Moray, N.; Richards, M.; Brophy, C.

    1984-01-01

    A model is described which predicts the allocation of attention to the features of a radar display. It uses the growth of uncertainty and the probability of near collision to call the eye to a feature of the display. The main source of uncertainty is forgetting following a fixation, which is modelled as a two dimensional diffusion process. The model was used to predict information overload in intercept controllers, and preliminary validation obtained by recording eye movements of intercept controllers in simulated and live (practice) interception.

  18. Drag and drop display & builder

    Energy Technology Data Exchange (ETDEWEB)

    Bolshakov, Timofei B.; Petrov, Andrey D.; /Fermilab

    2007-12-01

    The Drag and Drop (DnD) Display & Builder is a component-oriented system that allows users to create visual representations of data received from data acquisition systems. It is an upgrade of a Synoptic Display mechanism used at Fermilab since 2002. Components can be graphically arranged and logically interconnected in the web-startable Project Builder. Projects can be either lightweight AJAX- and SVG-based web pages, or they can be started as Java applications. The new version was initiated as a response to discussions between the LHC Controls Group and Fermilab.

  19. NIST display colorimeter calibration facility

    Science.gov (United States)

    Brown, Steven W.; Ohno, Yoshihiro

    2003-07-01

    A facility has been developed at the National Institute of Standards and Technology (NIST) to provide calibration services for color-measuring instruments to address the need for improving and certifying the measurement uncertainties of this type of instrument. While NIST has active programs in photometry, flat panel display metrology, and color and appearance measurements, these are the first services offered by NIST tailored to color-measuring instruments for displays. An overview of the facility, the calibration approach, and associated uncertainties are presented. Details of a new tunable colorimetric source and the development of new transfer standard instruments are discussed.

  20. Strategies to distinguish new synthetic cannabinoid FUBIMINA (BIM-2201) intake from its isomer THJ-2201: metabolism of FUBIMINA in human hepatocytes.

    Science.gov (United States)

    Diao, Xingxing; Scheidweiler, Karl B; Wohlfarth, Ariane; Zhu, Mingshe; Pang, Shaokun; Huestis, Marilyn A

    Since 2013, a new drugs-of-abuse trend attempts to bypass drug legislation by marketing isomers of scheduled synthetic cannabinoids (SCs), e.g., FUBIMINA (BIM-2201) and THJ-2201. It is much more challenging to confirm a specific isomer's intake and distinguish it from its structural analog because the isomers and their major metabolites usually have identical molecular weights and display the same product ions. Here, we investigated isomers FUBIMINA and THJ-2201 and propose strategies to distinguish their consumption. THJ-2201 was scheduled in the US, Japan, and Europe; however, FUBIMINA is easily available on the Internet. We previously investigated THJ-2201 metabolism in human hepatocytes, but human FUBIMINA metabolism is unknown. We aim to characterize FUBIMINA metabolism in human hepatocytes, recommend optimal metabolites to confirm its consumption, and propose strategies to distinguish between intakes of FUBIMINA and THJ-2201. FUBIMINA (10 μM) was incubated in human hepatocytes for 3 h, and metabolites were characterized with high-resolution mass spectrometry (HR-MS). We identified 35 metabolites generated by oxidative defluorination, further carboxylation, hydroxylation, dihydrodiol formation, glucuronidation, and their combinations. We recommend 5'-OH-BIM-018 (M34), BIM-018 pentanoic acid (M33), and BIM-018 pentanoic acid dihydrodiol (M7) as FUBIMINA specific metabolites. THJ-2201 produced specific metabolite markers 5'-OH-THJ-018 (F26), THJ-018 pentanoic acid (F25), and hydroxylated THJ-2201 (F13). Optimized chromatographic conditions to achieve different retention times and careful selection of specific product ion spectra enabled differentiation of isomeric metabolites, in this case FUBIMINA from THJ-2201. Our HR-MS approach should be applicable for differentiating future isomeric SCs, which is especially important when different isomers have different legal status.

  1. Genetic Nrf2 Overactivation Inhibits the Deleterious Effects Induced by Hepatocyte-Specific c-met Deletion during the Progression of NASH

    Directory of Open Access Journals (Sweden)

    Pierluigi Ramadori

    2017-01-01

    Full Text Available We have recently shown that hepatocyte-specific c-met deficiency accelerates the progression of nonalcoholic steatohepatitis in experimental murine models resulting in augmented production of reactive oxygen species and accelerated development of fibrosis. The aim of this study focuses on the elucidation of the underlying cellular mechanisms driven by Nrf2 overactivation in hepatocytes lacking c-met receptor characterized by a severe unbalance between pro-oxidant and antioxidant functions. Control mice (c-metfx/fx, single c-met knockouts (c-metΔhepa, and double c-met/Keap1 knockouts (met/Keap1Δhepa were then fed a chow or a methionine-choline-deficient (MCD diet, respectively, for 4 weeks to reproduce the features of nonalcoholic steatohepatitis. Upon MCD feeding, met/Keap1Δhepa mice displayed increased liver mass albeit decreased triglyceride accumulation. The marked increase of oxidative stress observed in c-metΔhepa was restored in the double mutants as assessed by 4-HNE immunostaining and by the expression of genes responsible for the generation of free radicals. Moreover, double knockout mice presented a reduced amount of liver-infiltrating cells and the exacerbation of fibrosis progression observed in c-metΔhepa livers was significantly inhibited in met/Keap1Δhepa. Therefore, genetic activation of the antioxidant transcription factor Nrf2 improves liver damage and repair in hepatocyte-specific c-met-deficient mice mainly through restoring a balance in the cellular redox homeostasis.

  2. Requirements of glycerol and fatty acid for triglyceride synthesis and ketogenesis by hepatocytes from normal and triiodothyronine-treated rats

    International Nuclear Information System (INIS)

    Olubadewo, J.O.; Heimberg, M.

    1985-01-01

    Hepatocytes from T3-treated rats synthesized less triglyceride and more ketone bodies from [1- 14 C]oleate at all concentrations from 0-2 mM, than did hepatocytes from euthyroid animals; addition of 1.0 mM glycerol increased triglyceride synthesis and reduced ketogenesis in hepatocytes from T3-treated rats to the rates observed in euthyroid hepatocytes in the absence of added glycerol. Glycerol did not alter triglyceride synthesis, but reduced ketogenesis genesis by euthyroid hepatocytes. It is probable from these and other data that, in the hyperthyroid rat, glycero-3-P, and not fatty acid, is rate limiting for synthesis of triglyceride, and, secondarily for reducing rates of ketogenesis in the hepatocyte

  3. Somatomedin-C stimulates glycogen synthesis in fetal rat hepatocytes

    International Nuclear Information System (INIS)

    Freemark, M.; D'Ercole, A.J.; Handwerger, S.

    1985-01-01

    The effects of somatomedin-C/insulin-like growth factor I (Sm-C) on glycogen metabolism in cultured hepatocytes from 20-day-old rat fetuses have been examined and compared with the effects of insulin. Sm-C (25-375 ng/ml; 3.25-50 nM) stimulated dose-dependent increases in [ 14 C]glucose incorporation into glycogen (14.4-72.9% and total cell glycogen content (10.6-34.3%. Maximal stimulation of glycogen synthesis by Sm-C occurred at 2-4 h of incubation. Insulin (10 nM to 10 microM) also stimulated [ 14 C]glucose incorporation but its potency was only 1/20th that of Sm-C. The time course of stimulation of glucose incorporation by insulin was identical to that of Sm-C, the dose-response curves of the two hormones were parallel, and the maximal effects of insulin were not enhanced by simultaneous exposure of cells to Sm-C. These findings suggest that Sm-C and insulin stimulate glycogenesis in fetal liver through similar or identical mechanisms. Since the potency of Sm-C was 20 times greater than that of insulin, the glycogenic action of insulin in fetal liver may be mediated through binding to a hepatic receptor which also binds Sm-C. In addition to having mitogenic effects on fetal tissues, Sm-C may have direct anabolic effects on fetal carbohydrate metabolism

  4. Protein phosphorylation in isolated hepatocytes of septic and endotoxemic rats

    International Nuclear Information System (INIS)

    Deaciuc, I.V.; Spitzer, J.A.

    1989-01-01

    The purpose of this study was to investigate possible alterations induced by sepsis and endotoxicosis in the late phase of Ca2+-dependent signaling in rat liver. Hepatocytes isolated from septic or chronically endotoxin (ET)-treated rats were labeled with [32P]H3PO4 and stimulated with various agents. Proteins were resolved by one-dimensional polyacrylamide gel electrophoresis and autoradiographed. Vasopressin (VP)- and phenylephrine (PE)-induced responses were attenuated in both septic and ET-treated rats for cytosolic and membrane proteins compared with their respective controls. Glucagon and 12-O-myristate phorbol-13-acetate (TPA) affected only the phosphorylation of membrane proteins. Glucagon-induced changes in the phosphorylation of membrane proteins were affected by both sepsis and endotoxicosis, whereas TPA-stimulated phosphorylation was lowered only in endotoxicosis. Response to the Ca2+ ionophore A23187 was depressed in septic rats for cytosolic proteins. The phosphorylation of two cytosolic proteins, i.e., 93 and 61 kDa (previously identified as glycogen phosphorylase and pyruvate kinase, respectively), in response to VP, PE, and A23187 was severely impaired by endotoxicosis and sepsis. TPA did not affect the phosphorylation state of these two proteins. The results show that sepsis and endotoxicosis produce perturbations of the phosphorylation step in Ca2+ transmembrane signaling. Such changes can explain alterations of glycogenolysis and gluconeogenesis associated with sepsis and endotoxicosis

  5. Stabilization of glucocorticoid receptors in isolated rat hepatocytes by radioprotectants

    International Nuclear Information System (INIS)

    Karle, J.M.; Ridder, W.E.; Wright, N.; Olmeda, R.; Nielsen, C.J.

    1986-01-01

    Previous work has shown that glucocorticoid receptors in rat liver homogenate can be stabilized by the addition of MoO 4 plus the sulfhydryl-containing compounds dithiothreitol and WR 1065. The latter is the dephosphorylated, principal metabolite of the radioprotectant WR 2721 (or S-2-(3-aminopropylamino)ethanesphosphorothioic acid). The current work results from applying this knowledge to intact rat hepatocytes. Cells were isolated by collagenase perfusion and incubated in supplemented minimum essential medium at 37 0 C with various concentrations of WR 2721, WR 1065, or vehicle. Samples of these cell suspensions were analyzed at various times for steroid binding capacity by incubating homogenates (27,000 x g supernates) with 50 nM 3 H-triamcinolone acetonide in the presence or absence of excess unlabelled dexamethasone. Concentrations of 10 mM WR 2721 provided marked preservation of the binding capacity (>85% of the initial value at 5 hours) compared to control at 60% of the binding capacity. WR 1065 at 10 mM provided no such protection. This is consistent with the observation that WR 1065 does not pass cell membranes. The authors propose that supplying reducing equivalents to intracellular components such as the glucocorticoid receptor may be one mechanism of the radioprotection afforded by WR 2721

  6. Relationship of histochemically detectable altered hepatocyte foci to hepatic tumorigenesis

    Energy Technology Data Exchange (ETDEWEB)

    Peraino, C.; Staffeldt, E.F.; Carnes, B.A.; Ludeman, V.A.; Blomquist, J.A.; Vesselinovitch, S.D.

    1984-01-01

    A new experimental system was used to examine the stages of chemically induced hepatic neoplasia in the rat. The treatment protocol involved the intraperitoneal injection of a single non-necrogenic dose of carcinogen (N-nitrosodiethylamine (NDEA) or benzo(a)pyrene (BP)) into male and female rats within one day after birth, followed by dietary exposure to promoter (0.05% phenobarbital) from weaning. Rats were killed at intervals, and their livers were examined for tumors and for histochemically detectable foci of altered hepatocytes. The data showed that (1) the new treatment protocol was highly efficient in foci and tumor production; (2) growth rates and incidence levels of foci were directly related to hepatocarcinogenic effectiveness (NDEA > BP), whereas both carcinogens had similar effects on foci phenotypic properties; (3) after their formation, foci at a given level of phenotypic complexity did not become progressively more complex; (4) incidence levels of foci were sex-dependent (females > males), but growth rates of foci were the same for both sexes; (5) growth rates and growth capacities (ranges of possible growth rates) of foci were directly related to phenotypic complexity levels of foci; (6) frequencies and phenotypic complexities of foci were inversely related; the reverse was true for tumors, although 10% of the tumors were relatively simple (three markers or fewer); (7) marker frequency distribution patterns were completely different in foci and in tumors.

  7. Anabolic regulation of gluconeogenesis by insulin in isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Mohan, C.; Bessman, S.P.

    1985-01-01

    The role of substrate availability in the regulation of gluconeogenesis in isolated rat hepatocytes was studied using [U- 14 C]alanine as a tracer in the presence of different concentrations of L-alanine in the incubation medium. At low alanine concentrations (0.5 mM) insulin decreased the 14 C incorporation into the glucose pool and increased the incorporation of tracer carbons into the protein and lipid pools and into CO 2 . The net radioactivity lost from the glucose pool was only a small percentage of the total increase in the activity of the protein, lipid, CO 2 , or glycogen pools, supporting the notion that the effect of insulin in diminishing gluconeogenesis is secondary to its effects on pathways using pyruvate. At higher concentrations of alanine (2.5, 5.0, and 10.0 mM) in the incubation medium insulin increased the movement of alanine carbons into protein and glucose. These results were further confirmed by using [U- 14 C]lactate. The increases in observed specific activity of glucose following insulin administration would not be possible if insulin acted by affecting the activity of any enzyme directly involved in the formation or utilization of pyruvate, most of which have been proposed as sites of insulin action. Data presented show that insulin inhibits gluconeogenesis by affecting a change in substrate availability

  8. Nuclear lactate dehydrogenase modulates histone modification in human hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Castonguay, Zachary; Auger, Christopher; Thomas, Sean C.; Chahma, M’hamed; Appanna, Vasu D., E-mail: vappanna@laurentian.ca

    2014-11-07

    Highlights: • Nuclear LDH is up-regulated under oxidative stress. • SIRT1 is co-immunoprecipitated bound to nuclear LDH. • Nuclear LDH is involved in histone deacetylation and epigenetics. - Abstract: It is becoming increasingly apparent that the nucleus harbors metabolic enzymes that affect genetic transforming events. Here, we describe a nuclear isoform of lactate dehydrogenase (nLDH) and its ability to orchestrate histone deacetylation by controlling the availability of nicotinamide adenine dinucleotide (NAD{sup +}), a key ingredient of the sirtuin-1 (SIRT1) deacetylase system. There was an increase in the expression of nLDH concomitant with the presence of hydrogen peroxide (H{sub 2}O{sub 2}) in the culture medium. Under oxidative stress, the NAD{sup +} generated by nLDH resulted in the enhanced deacetylation of histones compared to the control hepatocytes despite no discernable change in the levels of SIRT1. There appeared to be an intimate association between nLDH and SIRT1 as these two enzymes co-immunoprecipitated. The ability of nLDH to regulate epigenetic modifications by manipulating NAD{sup +} reveals an intricate link between metabolism and the processing of genetic information.

  9. Translation of mitochondrial proteins in digitonin-treated rat hepatocytes

    International Nuclear Information System (INIS)

    Kuzela, S.; Wielburski, A.; Nelson, B.D.

    1981-01-01

    Although it is now clear that up to 13 peptides may be encoded in mammalian mitochondrial DNA there is little agreement concerning the numbers of stable translation products detectable in these mitochondria. Part of this uncertainty is due to the low rates of labeling of mammalian mitochondrial translations products resulting from the relatively slow growth rates of mammalian cells. Indeed, it is often necessary to isolate mammalian mitochondria in order to analyze their translation products, and the isolation procedures could conceivably lead to artifacts from proteolysis or from the early release of nascent peptides. To circumvent this problem, it would be desirable to have available a mammalian system which combines the advantage of high rates of labeling of mitochondrial proteins with rapid preparation times. The authors report the novel use of digitonin-treated rat hepatocytes, which provide such a system. This preparation, which is complete in <10 min, does not carry out cytosolic protein synthesis, but labels mitochondrial translation products at rates much higher than intact cells or isolated, in vitro labeled mitochondria. (Auth.)

  10. Hepatocyte cotransport of taurocholate and bilirubin glucuronides: Role of microtubules

    International Nuclear Information System (INIS)

    Crawford, J.M.; Gollan, J.L.

    1988-01-01

    Modulation of bile pigment excretion by bile salts has been attributed to modification of canalicular membrane transport or a physical interaction in bile. Based on the observation that a microtubule-dependent pathway is involved in the hepatocellular transport of bile salts, the authors investigated the possibility that bilirubin glucuronides are associated with bile salts during intracellular transport. Experiments were conducted in intact rats (basal) or after overnight biliary diversion and intravenous reinfusion of taurocholate (depleted/reinfused). All rats were pretreated with intravenous low-dose colchicine or its inactive isomer lumicolchicine. Biliary excretion of radiolabeled bilirubin glucuronides derived from tracer [ 14 C]bilirubin-[ 3 H]bilirubin monoglucuronide (coinjected iv) was unchanged in basal rats but was consistently delayed in depleted/reinfused rats. This was accompanied by a significant shift toward bilirubin diglucuronide formation from both substrates. In basal Gunn rats, with deficient bilirubin glucuronidation, biliary excretion of intravenous [ 14 C]bilirubin monoglucuronide-[ 3 H]bilirubin diglucuronide was unaffected by colchicine but was retarded in depleted/reinfused Gunn rats. Colchicine had no effect on the rate of bilirubin glucuronidation in vitro in rat liver microsomes. They conclude that a portion of the bilirubin glucuronides generated endogenously in hepatocytes or taken up directly from plasma may be cotransported with bile salts to the bile canalicular membrane via a microtubule-dependent mechanism

  11. [Cadmium citotoxicity in mice hepatocytes and implications on tropical environments].

    Science.gov (United States)

    Marcano, Letty; Faría, Clarisa de R; Carruyo, Ingrid; Montiel, Xiomara

    2006-06-01

    We analyzed phenotypic, structural and ultrastructural alterations induced by Cd+2 in hepatocytes extracted from Swiss Albino mice. Cadmium was given orally in watery solution of CdCl2 during 100 days at concentrations of 50 ppm, 100 ppm and 150 ppm. In controls, distilled water alone was used. The samples were processed with the paraffin inclusion and hematoxilin-eosin coloration techniques for light microscopy. For transmission electron microscopy we used the conventional technique. We found phenotypic (size and weight differences) and physiologic changes (muscular weakness, unrest); at the structural level we noticed loss of trabecular disposition and of lobulillar architecture, lymphocyte agglomeration, vacuolization, dilatation of sinusoid and central vein, among others. The ultrastructural study evidenced alterations coincident with those seen with light microscopy, which were accentuated with the increase of metal concentration: nucleolus with a high number of fibrillar centers (50 ppm); voluminous lipidic drops in the cytoplasm, loose endoplasmic rough reticulum, citoplasmatic vacuolization, altered lisosomes and peroxisomes (100 ppm); contracted nuclei with condensed cromatine, dilatation of intracellular space and mitochondria, and loss of fibrillar areas (150 ppm). Cadmium produces a toxic effect in the hepatic cells; the effect is more severe at higher concentration, leading to cellular necrosis.

  12. Hepatocyte growth factor in renal failure: promise and reality.

    Science.gov (United States)

    Vargas, G A; Hoeflich, A; Jehle, P M

    2000-04-01

    Can science discover some secrets of Greek mythology? In the case of Prometheus, we can now suppose that his amazing hepatic regeneration was caused by a peptide growth factor called hepatocyte growth factor (HGF). Increasing evidence indicates that HGF acts as a multifunctional cytokine on different cell types. This review addresses the molecular mechanisms that are responsible for the pleiotropic effects of HGF. HGF binds with high affinity to its specific tyrosine kinase receptor c-met, thereby stimulating not only cell proliferation and differentiation, but also cell migration and tumorigenesis. The three fundamental principles of medicine-prevention, diagnosis, and therapy-may be benefited by the rational use of HGF. In renal tubular cells, HGF induces mitogenic and morphogenetic responses. In animal models of toxic or ischemic acute renal failure, HGF acts in a renotropic and nephroprotective manner. HGF expression is rapidly up-regulated in the remnant kidney of nephrectomized rats, inducing compensatory growth. In a mouse model of chronic renal disease, HGF inhibits the progression of tubulointerstitial fibrosis and kidney dysfunction. Increased HGF mRNA transcripts were detected in mesenchymal and tubular epithelial cells of rejecting kidney. In transplanted patients, elevated HGF levels may indicate renal rejection. When HGF is considered as a therapeutic agent in human medicine, for example, to stimulate kidney regeneration after acute injury, strategies need to be developed to stimulate cell regeneration and differentiation without an induction of tumorigenesis.

  13. Acylation and metabolism of (n-6) fatty acids in hepatocytes

    International Nuclear Information System (INIS)

    Voss, A.C.; Sprecher, H.

    1986-01-01

    Isolated hepatocytes (5 x 10 6 in 2ml) from chow fed rats were incubated from 20 to 60 min. with increasing concentrations of [1- 14 C] labeled 18:2 (n-6), 18:3 (n-6) or 20:3 (n-6) to define optimum conditions for measuring acylation and metabolism to other (n-6) acids with subsequent incorporation into lipids. The triglycerides (TG) and phospholipids (PL) contained 157 and 80 nmols of 18:2 (n-6) and 6.0 and 6.1 nmols of other (n-6) acids, respectively, when cells were incubated with 0.3mM [1- 14 C] 18:2 (n-6) for 40 min. When cells were incubated with 0.3mM [1- 14 C] 18:2 (n-6) plus 0.15 to 0.45mM 18:3 (n-6) or 20:3 (n-6), the metabolism of 18:2 (n-6) to other (n-6) acids was inhibited but not totally abolished. These results may suggest that (n-6) acid made from linoleate do not totally equilibrate with exogenous 18:3 (n-6) or 20:3

  14. Display Apple M7649Zm

    CERN Multimedia

    2001-01-01

    It was Designed for the Power Mac G4. This Apple studio display gives you edge-to-edge distortion-free images. With more than 16.7 million colors and 1,280 x 1,024 dpi resolution, you view brilliant and bright images on this Apple 17-inch monitor.

  15. Information retrieval and display system

    Science.gov (United States)

    Groover, J. L.; King, W. L.

    1977-01-01

    Versatile command-driven data management system offers users, through simplified command language, a means of storing and searching data files, sorting data files into specified orders, performing simple or complex computations, effecting file updates, and printing or displaying output data. Commands are simple to use and flexible enough to meet most data management requirements.

  16. Crystal ball single event display

    International Nuclear Information System (INIS)

    Grosnick, D.; Gibson, A.; Allgower, C.; Alyea, J.; Argonne National Lab., IL

    1997-01-01

    The Single Event Display (SED) is a routine that is designed to provide information graphically about a triggered event within the Crystal Ball. The SED is written entirely in FORTRAN and uses the CERN-based HICZ graphing package. The primary display shows the amount of energy deposited in each of the NaI crystals on a Mercator-like projection of the crystals. Ten different shades and colors correspond to varying amounts of energy deposited within a crystal. Information about energy clusters is displayed on the crystal map by outlining in red the thirteen (or twelve) crystals contained within a cluster and assigning each cluster a number. Additional information about energy clusters is provided in a series of boxes containing useful data about the energy distribution among the crystals within the cluster. Other information shown on the event display include the event trigger type and data about π o 's and η's formed from pairs of clusters as found by the analyzer. A description of the major features is given, along with some information on how to install the SED into the analyzer

  17. GridOrbit public display

    DEFF Research Database (Denmark)

    Ramos, Juan David Hincapie; Tabard, Aurélien; Bardram, Jakob

    2010-01-01

    We introduce GridOrbit, a public awareness display that visualizes the activity of a community grid used in a biology laboratory. This community grid executes bioin-formatics algorithms and relies on users to donate CPU cycles to the grid. The goal of GridOrbit is to create a shared awareness about...

  18. Interference Phenomenon with Mobile Displays

    Science.gov (United States)

    Trantham, Kenneth

    2015-01-01

    A simple experiment is presented in which the spacing and geometric pattern of pixels in mobile displays is measured. The technique is based on optical constructive interference. While the experiment is another opportunity to demonstrate wave interference from a grating-like structure, this can also be used to demonstrate concepts of solid state…

  19. Synthetic vision display evaluation studies

    Science.gov (United States)

    Regal, David M.; Whittington, David H.

    1994-01-01

    The goal of this research was to help us understand the display requirements for a synthetic vision system for the High Speed Civil Transport (HSCT). Four experiments were conducted to examine the effects of different levels of perceptual cue complexity in displays used by pilots in a flare and landing task. Increased levels of texture mapping of terrain and runway produced mixed results, including harder but shorter landings and a lower flare initiation altitude. Under higher workload conditions, increased texture resulted in an improvement in performance. An increase in familiar size cues did not result in improved performance. Only a small difference was found between displays using two patterns of high resolution texture mapping. The effects of increased perceptual cue complexity on performance was not as strong as would be predicted from the pilot's subjective reports or from related literature. A description of the role of a synthetic vision system in the High Speed Civil Transport is provide along with a literature review covering applied research related to perceptual cue usage in aircraft displays.

  20. Solar active region display system

    Science.gov (United States)

    Golightly, M.; Raben, V.; Weyland, M.

    2003-04-01

    The Solar Active Region Display System (SARDS) is a client-server application that automatically collects a wide range of solar data and displays it in a format easy for users to assimilate and interpret. Users can rapidly identify active regions of interest or concern from color-coded indicators that visually summarize each region's size, magnetic configuration, recent growth history, and recent flare and CME production. The active region information can be overlaid onto solar maps, multiple solar images, and solar difference images in orthographic, Mercator or cylindrical equidistant projections. Near real-time graphs display the GOES soft and hard x-ray flux, flare events, and daily F10.7 value as a function of time; color-coded indicators show current trends in soft x-ray flux, flare temperature, daily F10.7 flux, and x-ray flare occurrence. Through a separate window up to 4 real-time or static graphs can simultaneously display values of KP, AP, daily F10.7 flux, GOES soft and hard x-ray flux, GOES >10 and >100 MeV proton flux, and Thule neutron monitor count rate. Climatologic displays use color-valued cells to show F10.7 and AP values as a function of Carrington/Bartel's rotation sequences - this format allows users to detect recurrent patterns in solar and geomagnetic activity as well as variations in activity levels over multiple solar cycles. Users can customize many of the display and graph features; all displays can be printed or copied to the system's clipboard for "pasting" into other applications. The system obtains and stores space weather data and images from sources such as the NOAA Space Environment Center, NOAA National Geophysical Data Center, the joint ESA/NASA SOHO spacecraft, and the Kitt Peak National Solar Observatory, and can be extended to include other data series and image sources. Data and images retrieved from the system's database are converted to XML and transported from a central server using HTTP and SOAP protocols, allowing

  1. Display Sharing: An Alternative Paradigm

    Science.gov (United States)

    Brown, Michael A.

    2010-01-01

    The current Johnson Space Center (JSC) Mission Control Center (MCC) Video Transport System (VTS) provides flight controllers and management the ability to meld raw video from various sources with telemetry to improve situational awareness. However, maintaining a separate infrastructure for video delivery and integration of video content with data adds significant complexity and cost to the system. When considering alternative architectures for a VTS, the current system's ability to share specific computer displays in their entirety to other locations, such as large projector systems, flight control rooms, and back supporting rooms throughout the facilities and centers must be incorporated into any new architecture. Internet Protocol (IP)-based systems also support video delivery and integration. IP-based systems generally have an advantage in terms of cost and maintainability. Although IP-based systems are versatile, the task of sharing a computer display from one workstation to another can be time consuming for an end-user and inconvenient to administer at a system level. The objective of this paper is to present a prototype display sharing enterprise solution. Display sharing is a system which delivers image sharing across the LAN while simultaneously managing bandwidth, supporting encryption, enabling recovery and resynchronization following a loss of signal, and, minimizing latency. Additional critical elements will include image scaling support, multi -sharing, ease of initial integration and configuration, integration with desktop window managers, collaboration tools, host and recipient controls. This goal of this paper is to summarize the various elements of an IP-based display sharing system that can be used in today's control center environment.

  2. JTEC panel on display technologies in Japan

    Science.gov (United States)

    Tannas, Lawrence E., Jr.; Glenn, William E.; Credelle, Thomas; Doane, J. William; Firester, Arthur H.; Thompson, Malcolm

    1992-01-01

    This report is one in a series of reports that describes research and development efforts in Japan in the area of display technologies. The following are included in this report: flat panel displays (technical findings, liquid crystal display development and production, large flat panel displays (FPD's), electroluminescent displays and plasma panels, infrastructure in Japan's FPD industry, market and projected sales, and new a-Si active matrix liquid crystal display (AMLCD) factory); materials for flat panel displays (liquid crystal materials, and light-emissive display materials); manufacturing and infrastructure of active matrix liquid crystal displays (manufacturing logistics and equipment); passive matrix liquid crystal displays (LCD basics, twisted nematics LCD's, supertwisted nematic LCD's, ferroelectric LCD's, and a comparison of passive matrix LCD technology); active matrix technology (basic active matrix technology, investment environment, amorphous silicon, polysilicon, and commercial products and prototypes); and projection displays (comparison of Japanese and U.S. display research, and technical evaluation of work).

  3. Ruggedized Full-Color Flexible OLED Display

    National Research Council Canada - National Science Library

    Hack, Michael

    2003-01-01

    .... The team comprised Universal Display Corporation, Princeton University, the University of Southern California, Penn State University, L3 Displays and Vitex Systems, and was led by Universal Display Corporation (PI: Michael Hack...

  4. Effect of hepatocyte growth factor on radiation response of HeLa, V79, CHO and primary cultured parenchymal hepatocyte in vitro

    International Nuclear Information System (INIS)

    Yamazaki, Hideya; Inoue, Takehiro; Nose, Takayuki; Murayama, Shigeyuki; Teshima, Teruki; Ozeki, Syuji; Koizumi, Masahiko; Inoue, Toshihiko.

    1996-01-01

    Hepatocyte growth factor (HGF) is a multipotent cytokine enhancing regeneration of injured organs as liver, kidney and lung after injury. HGF enhances proliferation of various type of cells, inhibits proliferation of carcinoma cells, enhances motility of epithelial cells. We examined three cell lines (CHO, HeLa, V79) and primary cultured normal rat parenchymal hepatocytes to determine the effect of HGF on radiation response. HGF diminished survival of CHO and V79 cells determined by colony formation assay, whereas no significant change of survival was found in HeLa cells. No synergistic changes of survival were found when these three cell lines were irradiated with the addition of HGF. Thus, HGF did not enhance the radiation effect. We also analyzed the impact of irradiation with HGF on primary cultured normal rat parenchymal hepatocytes. At first, the release of glutamic-oxaloacetic amino-transaminase (GOT) in the supernatant was estimated. Irradiation (40 Gy) with or without HGF did not change GOT release in acute phase by 4 days after irradiation compared with the unirradiated control. Second, the DNA synthesis of rat parenchymal hepatocytes was analyzed using radioactive iodine-labeled deoxyuridine incorporation. HGF counteracted the suppression of DNA synthesis induced by irradiation. Thus, HGF may act as a mitogen even for irradiation-damaged normal cells. (author)

  5. Lipopolysaccharide stimulates p62-dependent autophagy-like aggregate clearance in hepatocytes.

    Science.gov (United States)

    Chen, Christine; Deng, Meihong; Sun, Qian; Loughran, Patricia; Billiar, Timothy R; Scott, Melanie J

    2014-01-01

    Impairment of autophagy has been associated with liver injury. TLR4-stimulation by LPS upregulates autophagy in hepatocytes, although the signaling pathways involved remain elusive. The objective of this study was to determine the signaling pathway leading to LPS-stimulated autophagy in hepatocytes. Cell lysates from livers of wild type (WT; C57BL/6) mice given LPS (5 mg/kg-IP) and hepatocytes from WT, TLR4ko, and MyD88ko mice treated with LPS (100 ng/mL) up to 24 h were collected. LC3II, p62/SQSTM1, Nrf2, and beclin1 levels were determined by immunoblot, immunofluorescence, and qPCR. Autophagy-like activation was measured by GFP-LC3-puncta formation and LC3II-expression. Beclin1, Nrf2, p62, MyD88, and TIRAP were knocked-down using siRNA. LC3II-expression increased in both liver and hepatocytes after LPS and was dependent on TLR4. Beclin1 expression did not increase after LPS in hepatocytes and beclin1-knockdown did not affect LC3II levels. In hepatocytes given LPS, expression of p62 increased and p62 colocalized with LC3. p62-knockdown prevented LC3II puncta formation. LPS-induced LC3II/p62-puncta also required MyD88/TIRAP signaling and localization of both Nrf2 and NF κ B transcription factors to the nucleus to upregulate p62-expression. Therefore, TLR4-activation by LPS in hepatocytes induces a p62-mediated, not beclin1-mediated, autophagy-like clearance pathway that is hepatoprotective by clearing aggregate-prone or misfolded proteins from the cytosol and preserving energy homeostasis under stress.

  6. DISTINCT FUNCTIONS OF JNK AND C-JUN IN OXIDANT-INDUCED HEPATOCYTE DEATH

    Science.gov (United States)

    Amir, Muhammad; Liu, Kun; Zhao, Enpeng; Czaja, Mark J.

    2013-01-01

    Overactivation of c-Jun N-terminal kinase (JNK)/c-Jun signaling is a central mechanism of hepatocyte injury and death including that from oxidative stress. However, the functions of JNK and c-Jun are still unclear, and this pathway also inhibits hepatocyte death. Previous studies of menadione-induced oxidant stress demonstrated that toxicity resulted from sustained JNK/c-Jun activation as death was blocked by the c-Jun dominant negative TAM67. To further delineate the function of JNK/c-Jun signaling in hepatocyte injury from oxidant stress, the effects of direct JNK inhibition on menadione-induced death were examined. In contrast to the inhibitory effect of TAM67, pharmacological JNK inhibition by SP600125 sensitized the rat hepatocyte cell line RALA255-10G to death from menadione. SP600125 similarly sensitized mouse primary hepatocytes to menadione toxicity. Death from SP600125/menadione was c-Jun dependent as it was blocked by TAM67, but independent of c-Jun phosphorylation. Death occurred by apoptosis and necrosis and activation of the mitochondrial death pathway. Short hairpin RNA knockdowns of total JNK or JNK2 sensitized to death from menadione, whereas a jnk1 knockdown was protective. Jnk2 null mouse primary hepatocytes were also sensitized to menadione death. JNK inhibition magnified decreases in cellular ATP content and β-oxidation induced by menadione. This effect mediated cell death as chemical inhibition of β-oxidation also sensitized cells to death from menadione, and supplementation with the β-oxidation substrate oleate blocked death. Components of the JNK/c-Jun signaling pathway have opposing functions in hepatocyte oxidant stress with JNK2 mediating resistance to cell death and c-Jun promoting death. PMID:22644775

  7. Functional properties of hepatocytes in vitro are correlated with cell polarity maintenance.

    Science.gov (United States)

    Zeigerer, Anja; Wuttke, Anne; Marsico, Giovanni; Seifert, Sarah; Kalaidzidis, Yannis; Zerial, Marino

    2017-01-01

    Exploring the cell biology of hepatocytes in vitro could be a powerful strategy to dissect the molecular mechanisms underlying the structure and function of the liver in vivo. However, this approach relies on appropriate in vitro cell culture systems that can recapitulate the cell biological and metabolic features of the hepatocytes in the liver whilst being accessible to experimental manipulations. Here, we adapted protocols for high-resolution fluorescence microscopy and quantitative image analysis to compare two primary hepatocyte culture systems, monolayer and collagen sandwich, with respect to the distribution of two distinct populations of early endosomes (APPL1 and EEA1-positive), endocytic capacity, metabolic and signaling activities. In addition to the re-acquisition of hepatocellular polarity, primary hepatocytes grown in collagen sandwich but not in monolayer culture recapitulated the apico-basal distribution of EEA1 endosomes observed in liver tissue. We found that such distribution correlated with the organization of the actin cytoskeleton in vitro and, surprisingly, was dependent on the nutritional state in vivo. Hepatocytes in collagen sandwich also exhibited faster kinetics of low-density lipoprotein (LDL) and epidermal growth factor (EGF) internalization, showed improved insulin sensitivity and preserved their ability for glucose production, compared to hepatocytes in monolayer cultures. Although no in vitro culture system can reproduce the exquisite structural features of liver tissue, our data nevertheless highlight the ability of the collagen sandwich system to recapitulate key structural and functional properties of the hepatocytes in the liver and, therefore, support the usage of this system to study aspects of hepatocellular biology in vitro. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  8. Oxidative stress is involved in Dasatinib-induced apoptosis in rat primary hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Xue, Tao; Luo, Peihua; Zhu, Hong; Zhao, Yuqin [Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Wu, Honghai; Gai, Renhua; Wu, Youping [Center for Drug Safety Evaluation and Research of Zhejiang University, Hangzhou 310058 (China); Yang, Bo [Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Yang, Xiaochun, E-mail: yangxiaochun@zju.edu.cn [Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Center for Drug Safety Evaluation and Research of Zhejiang University, Hangzhou 310058 (China); He, Qiaojun, E-mail: qiaojunhe@zju.edu.cn [Institute of Pharmacology and Toxicology, College of Pharmaceutical Sciences, Zhejiang University, Hangzhou 310058 (China); Center for Drug Safety Evaluation and Research of Zhejiang University, Hangzhou 310058 (China)

    2012-06-15

    Dasatinib, a multitargeted inhibitor of BCR–ABL and SRC kinases, exhibits antitumor activity and extends the survival of patients with chronic myeloid leukemia (CML) and Philadelphia chromosome-positive acute lymphoblastic leukemia (ALL). However, some patients suffer from hepatotoxicity, which occurs through an unknown mechanism. In the present study, we found that Dasatinib could induce hepatotoxicity both in vitro and in vivo. Dasatinib reduced the cell viability of rat primary hepatocytes, induced the release of alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) in vitro, and triggered the ballooning degeneration of hepatocytes in Sprague–Dawley rats in vivo. Apoptotic markers (chromatin condensation, cleaved caspase-3 and cleaved PARP) were detected to indicate that the injury induced by Dasatinib in hepatocytes in vitro was mediated by apoptosis. This result was further validated in vivo using terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assays. Here we found that Dasatinib dramatically increased the level of reactive oxygen species (ROS) in hepatocytes, reduced the intracellular glutathione (GSH) content, attenuated the activity of superoxide dismutase (SOD), generated malondialdehyde (MDA), a product of lipid peroxidation, decreased the mitochondrial membrane potential, and activated nuclear factor erythroid 2-related factor 2 (Nrf2) and mitogen-activated protein kinases (MAPK) related to oxidative stress and survival. These results confirm that oxidative stress plays a pivotal role in Dasatinib-mediated hepatotoxicity. N-acetylcysteine (NAC), a typical antioxidant, can scavenge free radicals, attenuate oxidative stress, and protect hepatocytes against Dasatinib-induced injury. Thus, relieving oxidative stress is a viable strategy for reducing Dasatinib-induced hepatotoxicity. -- Highlights: ►Dasatinib shows potential hepatotoxicity both in vitro and in vivo. ►Apoptosis plays a vital role in Dasatinib

  9. Oncostatin M induces upregulation of claudin-2 in rodent hepatocytes coinciding with changes in morphology and function of tight junctions

    International Nuclear Information System (INIS)

    Imamura, Masafumi; Kojima, Takashi; Lan, Mengdong; Son, Seiichi; Murata, Masaki; Osanai, Makoto; Chiba, Hideki; Hirata, Koichi; Sawada, Norimasa

    2007-01-01

    In rodent livers, integral tight junction (TJ) proteins claudin-1, -2, -3, -5 and -14 are detected and play crucial roles in the barrier to keep bile in bile canaculi away from the blood circulation. Claudin-2 shows a lobular gradient increasing from periportal to pericentral hepatocytes, whereas claudin-1 and -3 are expressed in the whole liver lobule. Although claudin-2 expression induces cation-selective channels in tight junctions of epithelial cells, the physiological functions and regulation of claudin-2 in hepatocytes remain unclear. Oncostatin M (OSM) is a multifunctional cytokine implicated in the differentiation of hepatocytes that induces formation of E-cadherin-based adherens junctions in fetal hepatocytes. In this study, we examined whether OSM could induce expression and function of claudin-2 in rodent hepatocytes, immortalized mouse and primary cultured proliferative rat hepatocytes. In the immortalized mouse and primary cultured proliferative rat hepatocytes, treatment with OSM markedly increased mRNA and protein of claudin-2 together with formation of developed networks of TJ strands. The increase of claudin-2 enhanced the paracellular barrier function which depended on molecular size. The increase of claudin-2 expression induced by OSM in rodent hepatocytes was regulated through distinct signaling pathways including PKC. These results suggest that expression of claudin-2 in rodent hepatocytes may play a specific role as controlling the size of paracellular permeability in the barrier to keep bile in bile canaculi

  10. Improved human endometrial stem cells differentiation into functional hepatocyte-like cells on a glycosaminoglycan/collagen-grafted polyethersulfone nanofibrous scaffold.

    Science.gov (United States)

    Khademi, Farzaneh; Ai, Jafar; Soleimani, Masoud; Verdi, Javad; Mohammad Tavangar, Seyed; Sadroddiny, Esmaeil; Massumi, Mohammad; Mahmoud Hashemi, Seyed

    2017-11-01

    Liver tissue engineering (TE) is rapidly emerging as an effective technique which combines engineering and biological processes to compensate for the shortage of damaged or destroyed liver tissues. We examined the viability, differentiation, and integration of hepatocyte-like cells on an electrospun polyethersulfone (PES) scaffold, derived from human endometrial stem cells (hEnSCs). Natural polymers were separately grafted on plasma-treated PES nanofibers, that is, collagen, heparan sulfate (HS) and collagen-HS. Galactosilated PES (PES-Gal) nanofibrous were created. The engineering and cell growth parameters were considered and compared with each sample. The cellular studies revealed increased cell survival, attachment, and normal morphology on the bioactive natural polymer-grafted scaffolds after 30 days of hepatic differentiation. The chemical and molecular assays displayed hepatocyte differentiation. These cells were also functional, showing glycogen storage, α-fetoprotein, and albumin secretion. The HS nanoparticle-grafted PES nanofibers demonstrated a high rate of cell proliferation, differentiation, and integration. Based on the observations mentioned above, engineered tissue is a good option in the future, for the commercial production of three-dimensional liver tissues for clinical purposes. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2516-2529, 2017. © 2016 Wiley Periodicals, Inc.

  11. Effects of β-hydroxybutyricacid on the synthesis and assembly of very low-density lipoprotein in bovine hepatocytes in vitro.

    Science.gov (United States)

    Deng, Q; Ma, D; Shi, Z; Huang, W; Du, X; Gao, W; Zhu, X; Lei, L; Zhang, M; Sun, G; Yuan, X; Li, X; Wang, Z; Liu, G; Li, X

    2016-04-01

    β-Hydroxybutyricacid (BHBA) is an important metabolite that involved in the development of ketosis and fatty liver in dairy cows. Dairy cows with fatty liver displayed high blood concentration of BHBA and very low-density lipoprotein (VLDL) assembly. The effects of BHBA on VLDL synthesis and assembly in hepatocytes of cows were unclear. In this study, bovine hepatocytes were cultured and treated with different concentrations of BHBA. We found that BHBA treatment upregulated the mRNA and protein levels of apolipoprotein B100 (ApoB 100), apolipoprotein E (ApoE) and microsomal triglyceride transfer protein (MTTP) and showed in a firstly increased and then decreased trend. Meanwhile, the mRNA and protein levels of LDLR showed in a reverse trend. Consequently, VLDL content was significantly increased in medium-dose BHBA treatment group, while decreased in high-dose group. These results indicate that the effects of BHBA on the VLDL synthesis showed in a dose-dependent manner that low levels of BHBA increase VLDL synthesis and high levels of BHBA decrease VLDL synthesis. Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

  12. Renal medullary AA amyloidosis, hepatocyte dissociation and multinucleated hepatocytes in a 14-year-old free-ranging lioness (Panthera leo

    Directory of Open Access Journals (Sweden)

    J.H. Williams

    2005-06-01

    Full Text Available A 14-year-old lioness, originating from Etosha in Namibia, and a member of a pride in Pilanesberg National Park since translocation in 1994, was euthanased due to fight-related vertebral fracture and spinal injury, incurred approximately 6-8 weeks previously. Blood specimens collected at the time of death showed mild anaemia and a leukogram reflecting stress and chronic infection. Necropsy conducted within 2 hours of death was on a dehydrated, emaciated animal with hindquarter wasting and chronic traumatic friction injuries from dragging her hindlegs. There was cellulitis in the region of bite-wounds adjacent to the thoraco-lumbar vertebral fracture, at which site there was spinal cord compression, and there was marked intestinal helminthiasis. The outer renal medullae appeared pale and waxy and the liver was macroscopically unremarkable. Histopathology and electron microscopy of the kidneys revealed multifocal to coalescing deposits of proximal medullary interstitial amyloid, which fluoresced strongly with thioflavine T, and was sensitive to potassium permanganate treatment prior to Congo Red staining, thus indicating inflammatory (AA origin. There was diffuse hepatocyte dissociation, as well as numerous binucleated and scattered multinucleated (up to 8 nuclei/cell hepatocytes, with swollen hepatocyte mitochondria, in liver examined light microscopically. Ultrastructurally, the mono-, bi- and multinucleated hepatocytes contained multifocal irregular membrane-bound accumulations of finely-granular, amorphous material both intra-cytoplasmically and intra-nuclearly, as well as evidence of irreversible mitochondrial injury. The incidence and relevance in cats and other species of amyloidosis, particularly with renal medullary distribution, as well as of hepatocyte dissociation and multinucleation, as reported in selected literature, is briefly overviewed and their occurrence in this lioness is discussed.

  13. Reconfigurable Auditory-Visual Display

    Science.gov (United States)

    Begault, Durand R. (Inventor); Anderson, Mark R. (Inventor); McClain, Bryan (Inventor); Miller, Joel D. (Inventor)

    2008-01-01

    System and method for visual and audible communication between a central operator and N mobile communicators (N greater than or equal to 2), including an operator transceiver and interface, configured to receive and display, for the operator, visually perceptible and audibly perceptible signals from each of the mobile communicators. The interface (1) presents an audible signal from each communicator as if the audible signal is received from a different location relative to the operator and (2) allows the operator to select, to assign priority to, and to display, the visual signals and the audible signals received from a specified communicator. Each communicator has an associated signal transmitter that is configured to transmit at least one of the visual signals and the audio signal associated with the communicator, where at least one of the signal transmitters includes at least one sensor that senses and transmits a sensor value representing a selected environmental or physiological parameter associated with the communicator.

  14. Game engines and immersive displays

    Science.gov (United States)

    Chang, Benjamin; Destefano, Marc

    2014-02-01

    While virtual reality and digital games share many core technologies, the programming environments, toolkits, and workflows for developing games and VR environments are often distinct. VR toolkits designed for applications in visualization and simulation often have a different feature set or design philosophy than game engines, while popular game engines often lack support for VR hardware. Extending a game engine to support systems such as the CAVE gives developers a unified development environment and the ability to easily port projects, but involves challenges beyond just adding stereo 3D visuals. In this paper we outline the issues involved in adapting a game engine for use with an immersive display system including stereoscopy, tracking, and clustering, and present example implementation details using Unity3D. We discuss application development and workflow approaches including camera management, rendering synchronization, GUI design, and issues specific to Unity3D, and present examples of projects created for a multi-wall, clustered, stereoscopic display.

  15. The virtual environment display system

    Science.gov (United States)

    Mcgreevy, Michael W.

    1991-01-01

    Virtual environment technology is a display and control technology that can surround a person in an interactive computer generated or computer mediated virtual environment. It has evolved at NASA-Ames since 1984 to serve NASA's missions and goals. The exciting potential of this technology, sometimes called Virtual Reality, Artificial Reality, or Cyberspace, has been recognized recently by the popular media, industry, academia, and government organizations. Much research and development will be necessary to bring it to fruition.

  16. Live cell imaging of cytosolic NADH/NAD+ ratio in hepatocytes and liver slices.

    Science.gov (United States)

    Masia, Ricard; McCarty, William J; Lahmann, Carolina; Luther, Jay; Chung, Raymond T; Yarmush, Martin L; Yellen, Gary

    2018-01-01

    Fatty liver disease (FLD), the most common chronic liver disease in the United States, may be caused by alcohol or the metabolic syndrome. Alcohol is oxidized in the cytosol of hepatocytes by alcohol dehydrogenase (ADH), which generates NADH and increases cytosolic NADH/NAD + ratio. The increased ratio may be important for development of FLD, but our ability to examine this question is hindered by methodological limitations. To address this, we used the genetically encoded fluorescent sensor Peredox to obtain dynamic, real-time measurements of cytosolic NADH/NAD + ratio in living hepatocytes. Peredox was expressed in dissociated rat hepatocytes and HepG2 cells by transfection, and in mouse liver slices by tail-vein injection of adeno-associated virus (AAV)-encoded sensor. Under control conditions, hepatocytes and liver slices exhibit a relatively low (oxidized) cytosolic NADH/NAD + ratio as reported by Peredox. The ratio responds rapidly and reversibly to substrates of lactate dehydrogenase (LDH) and sorbitol dehydrogenase (SDH). Ethanol causes a robust dose-dependent increase in cytosolic NADH/NAD + ratio, and this increase is mitigated by the presence of NAD + -generating substrates of LDH or SDH. In contrast to hepatocytes and slices, HepG2 cells exhibit a relatively high (reduced) ratio and show minimal responses to substrates of ADH and SDH. In slices, we show that comparable results are obtained with epifluorescence imaging and two-photon fluorescence lifetime imaging (2p-FLIM). Live cell imaging with Peredox is a promising new approach to investigate cytosolic NADH/NAD + ratio in hepatocytes. Imaging in liver slices is particularly attractive because it allows preservation of liver microanatomy and metabolic zonation of hepatocytes. NEW & NOTEWORTHY We describe and validate a new approach for measuring free cytosolic NADH/NAD + ratio in hepatocytes and liver slices: live cell imaging with the fluorescent biosensor Peredox. This approach yields dynamic, real

  17. Activated human neutrophils release hepatocyte growth factor/scatter factor.

    LENUS (Irish Health Repository)

    McCourt, M

    2012-02-03

    BACKGROUND: Hepatocyte growth factor or scatter factor (HGF\\/SF) is a pleiotropic cytokine that has potent angiogenic properties. We have previously demonstrated that neutrophils (PMN) are directly angiogenic by releasing vascular endothelial growth factor (VEGF). We hypothesized that the acute inflammatory response can stimulate PMN to release HGF. AIMS: To examine the effects of inflammatory mediators on PMN HGF release and the effect of recombinant human HGF (rhHGF) on PMN adhesion receptor expression and PMN VEGF release. METHODS: In the first experiment, PMN were isolated from healthy volunteers and stimulated with tumour necrosis factor-alpha (TNF-alpha), lipopolysaccharide (LPS), interleukin-8 (IL-8), and formyl methionyl-leucyl-phenylalanine (fMLP). Culture supernatants were assayed for HGF using ELISA. In the second experiment, PMN were lysed to measure total HGF release and HGF expression in the PMN was detected by Western immunoblotting. Finally, PMN were stimulated with rhHGF. PMN CD 11a, CD 11b, and CD 18 receptor expression and VEGF release was measured using flow cytometry and ELISA respectively. RESULTS: TNF-alpha, LPS and fMLP stimulation resulted in significantly increased release of PMN HGF (755+\\/-216, 484+\\/-221 and 565+\\/-278 pg\\/ml, respectively) compared to controls (118+\\/-42 pg\\/ml). IL-8 had no effect. Total HGF release following cell lysis and Western blot suggests that HGF is released from intracellular stores. Recombinant human HGF did not alter PMN adhesion receptor expression and had no effect on PMN VEGF release. CONCLUSIONS: This study demonstrates that pro-inflammatory mediators can stimulate HGF release from a PMN intracellular store and that activated PMN in addition to secreting VEGF have further angiogenic potential by releasing HGF.

  18. Differentiation of hepatocytes from induced pluripotent stem cells derived from human hair follicle mesenchymal stem cells.

    Science.gov (United States)

    Shi, Xu; Lv, Shuang; He, Xia; Liu, Xiaomei; Sun, Meiyu; Li, Meiying; Chi, Guangfan; Li, Yulin

    2016-10-01

    Due to the limitations of organ donors and immune rejection in severe liver diseases, stem cell-based therapy presents a promising application for tissue repair and regeneration. As a novel cell source, mesenchymal stem cells separated from human hair follicles (HF-MSCs) are convenient to obtain and have no age limit. To date, the differentiation of HF-MSCs into hepatocytes has not been reported. In this study, we explored whether HF-MSCs and HF-MSC-derived-induced pluripotent stem cells (HF-iPS) could differentiate into hepatocytes in vitro. Flow cytometry, Oil Red O stain and Alizarin Red stain were used to identify the characteristics of HF-MSCs. The expression of liver-specific gene was detected by immunofluorescence and Quantitative Polymerase Chain Reaction. Periodic Acid-Schiff stain, Indocyanine Green stain and Low-Density Lipoprotein stain were performed to evaluate the functions of induced hepatocyte-like cells (HLCs). HF-MSCs were unable to differentiate into HLCs using previously reported procedures for MSCs from other tissues. However, HF-iPS efficiently induced the generation of HLCs that expressed hepatocyte markers and drug metabolism-related genes. HF-iPS can be used as novel and alternative cellular tools for inducing hepatocytes in vitro, simultaneously benefiting from utilizing HF-MSCs as a noninvasive and convenient cell source for reprogramming.

  19. Generation of human pluripotent stem cell-derived hepatocyte-like cells for drug toxicity screening.

    Science.gov (United States)

    Takayama, Kazuo; Mizuguchi, Hiroyuki

    2017-02-01

    Because drug-induced liver injury is one of the main reasons for drug development failures, it is important to perform drug toxicity screening in the early phase of pharmaceutical development. Currently, primary human hepatocytes are most widely used for the prediction of drug-induced liver injury. However, the sources of primary human hepatocytes are limited, making it difficult to supply the abundant quantities required for large-scale drug toxicity screening. Therefore, there is an urgent need for a novel unlimited, efficient, inexpensive, and predictive model which can be applied for large-scale drug toxicity screening. Human embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are able to replicate indefinitely and differentiate into most of the body's cell types, including hepatocytes. It is expected that hepatocyte-like cells generated from human ES/iPS cells (human ES/iPS-HLCs) will be a useful tool for drug toxicity screening. To apply human ES/iPS-HLCs to various applications including drug toxicity screening, homogenous and functional HLCs must be differentiated from human ES/iPS cells. In this review, we will introduce the current status of hepatocyte differentiation technology from human ES/iPS cells and a novel method to predict drug-induced liver injury using human ES/iPS-HLCs. Copyright © 2016 The Japanese Society for the Study of Xenobiotics. Published by Elsevier Ltd. All rights reserved.

  20. Prolongation of liver-specific function for primary hepatocytes maintenance in 3D printed architectures.

    Science.gov (United States)

    Kim, Yohan; Kang, Kyojin; Yoon, Sangtae; Kim, Ji Sook; Park, Su A; Kim, Wan Doo; Lee, Seung Bum; Ryu, Ki-Young; Jeong, Jaemin; Choi, Dongho

    2018-01-23

    Isolated primary hepatocytes from the liver are very similar to in vivo native liver hepatocytes, but they have the disadvantage of a limited lifespan in 2D culture. Although a sandwich culture and 3D organoids with mesenchymal stem cells (MSCs) as an attractive assistant cell source to extend lifespan can be used, it cannot fully reproduce the in vivo architecture. Moreover, long-term 3D culture leads to cell death because of hypoxic stress. Therefore, to overcome the drawback of 2D and 3D organoids, we try to use a 3D printing technique using alginate hydrogels with primary hepatocytes and MSCs. The viability of isolated hepatocytes was more than 90%, and the cells remained alive for 7 days without morphological changes in the 3D hepatic architecture with MSCs. Compared to a 2D system, the expression level of functional hepatic genes and proteins was higher for up to 7 days in the 3D hepatic architecture. These results suggest that both the 3D bio-printing technique and paracrine molecules secreted by MSCs supported long-term culture of hepatocytes without morphological changes. Thus, this technique allows for widespread expansion of cells while forming multicellular aggregates, may be applied to drug screening and could be an efficient method for developing an artificial liver.

  1. Glutamic Acid as Enhancer of Protein Synthesis Kinetics in Hepatocytes from Old Rats.

    Science.gov (United States)

    Brodsky, V Y; Malchenko, L A; Butorina, N N; Lazarev Konchenko, D S; Zvezdina, N D; Dubovaya, T K

    2017-08-01

    Dense cultures of hepatocytes from old rats (~2 years old, body weight 530-610 g) are different from similar cultures of hepatocytes from young rats by the low amplitude of protein synthesis rhythm. Addition of glutamic acid (0.2, 0.4, or 0.6 mg/ml) into the culture medium with hepatocytes of old rats resulted in increase in the oscillation amplitudes of the protein synthesis rhythm to the level of young rats. A similar action of glutamic acid on the protein synthesis kinetics was observed in vivo after feeding old rats with glutamic acid. Inhibition of metabotropic receptors of glutamic acid with α-methyl-4-carboxyphenylglycine (0.01 mg/ml) abolished the effect of glutamic acid. The amplitude of oscillation of the protein synthesis rhythm in a cell population characterizes synchronization of individual oscillations caused by direct cell-cell communications. Hence, glutamic acid, acting as a receptor-dependent transmitter, enhanced direct cell-cell communications of hepatocytes that were decreased with aging. As differentiated from other known membrane signaling factors (gangliosides, norepinephrine, serotonin, dopamine), glutamic acid can penetrate into the brain and thus influence the communications and protein synthesis kinetics that are disturbed with aging not only in hepatocytes, but also in neurons.

  2. Isolation of primary human hepatocytes from normal and diseased liver tissue: a one hundred liver experience.

    Directory of Open Access Journals (Sweden)

    Ricky H Bhogal

    2011-03-01

    Full Text Available Successful and consistent isolation of primary human hepatocytes remains a challenge for both cell-based therapeutics/transplantation and laboratory research. Several centres around the world have extensive experience in the isolation of human hepatocytes from non-diseased livers obtained from donor liver surplus to surgical requirement or at hepatic resection for tumours. These livers are an important but limited source of cells for therapy or research. The capacity to isolate cells from diseased liver tissue removed at transplantation would substantially increase availability of cells for research. However no studies comparing the outcome of human hepatocytes isolation from diseased and non-diseased livers presently exist. Here we report our experience isolating human hepatocytes from organ donors, non-diseased resected liver and cirrhotic tissue. We report the cell yields and functional qualities of cells isolated from the different types of liver and demonstrate that a single rigorous protocol allows the routine harvest of good quality primary hepatocytes from the most commonly accessible human liver tissue samples.

  3. Acquisition of lipid metabolic capability in hepatocyte-like cells directly induced from mouse fibroblasts

    Directory of Open Access Journals (Sweden)

    Shizuka eMiura

    2014-08-01

    Full Text Available Recently, the numbers of patients with non-alcoholic fatty liver disease (NAFLD and non-alcoholic steatohepatitis (NASH have increased worldwide. NAFLD and NASH are known as risk factors for liver cirrhosis and hepatocellular carcinoma. Because many factors can promote the progression of NAFLD and NASH, the treatment of these patients involves various strategies. Thus, it is desired that drugs for patients with NAFLD and NASH should be developed more easily and rapidly using cultures of primary hepatocytes. However, it is difficult to use hepatocytes as a tool for drug screening, because these cells cannot be functionally maintained in culture. Thus, in this study, we sought to examine whether induced hepatocyte-like (iHep cells, which were directly induced from mouse dermal fibroblasts by infection with a retrovirus expressing Hnf4α and Foxa3, possess the potential for lipid metabolism, similar to hepatocytes. Our data showed that iHep cells were capable of synthesizing lipids from a cis-unsaturated fatty acid, a trans-unsaturated fatty acid, and a saturated fatty acid, accumulating the synthesized lipids in cellular vesicles, and secreting the lipids into the culture medium. Moreover, the lipid synthesis in iHep cells was significantly inhibited in cultures with lipid metabolism improvers. These results demonstrate that iHep cells could be useful not only for screening of drugs for patients with NAFLD and NASH, but also for elucidation of the mechanisms underlying hereditary lipid metabolism disorders, as an alternative to hepatocytes.

  4. Evaluation and optimization of hepatocyte culture media factors by design of experiments (DoE) methodology.

    Science.gov (United States)

    Dong, Jia; Mandenius, Carl-Fredrik; Lübberstedt, Marc; Urbaniak, Thomas; Nüssler, Andreas K N; Knobeloch, Daniel; Gerlach, Jörg C; Zeilinger, Katrin

    2008-07-01

    Optimization of cell culture media based on statistical experimental design methodology is a widely used approach for improving cultivation conditions. We applied this methodology to refine the composition of an established culture medium for growth of a human hepatoma cell line, C3A. A selection of growth factors and nutrient supplements were systematically screened according to standard design of experiments (DoE) procedures. The results of the screening indicated that the medium additives hepatocyte growth factor, oncostatin M, and fibroblast growth factor 4 significantly influenced the metabolic activities of the C3A cell line. Surface response methodology revealed that the optimum levels for these factors were 30 ng/ml for hepatocyte growth factor and 35 ng/ml for oncostatin M. Additional experiments on primary human hepatocyte cultures showed high variance in metabolic activities between cells from different individuals, making determination of optimal levels of factors more difficult. Still, it was possible to conclude that hepatocyte growth factor, epidermal growth factor, and oncostatin M had decisive effects on the metabolic functions of primary human hepatocytes.

  5. Deletion of hepatocyte nuclear factor-1-beta in an infant with prune belly syndrome.

    Science.gov (United States)

    Haeri, Sina; Devers, Patricia L; Kaiser-Rogers, Kathleen A; Moylan, Vincent J; Torchia, Beth S; Horton, Amanda L; Wolfe, Honor M; Aylsworth, Arthur S

    2010-08-01

    Prune belly syndrome is a rare congenital disorder characterized by deficiency of abdominal wall muscles, cryptorchidism, and urinary tract anomalies. We have had the opportunity to study a baby with prune belly syndrome associated with an apparently de novo 1.3-megabase interstitial 17q12 microdeletion that includes the hepatocyte nuclear factor-1-beta gene at 17q12. One previous patient, an adult, has been reported with prune belly syndrome and a hepatocyte nuclear factor-1-beta microdeletion. Hepatocyte nuclear factor-1-beta is a widely expressed transcription factor that regulates tissue-specific gene expression and is expressed in numerous tissues including mesonephric duct derivatives, the renal tubule of the metanephros, and the developing prostate of the mouse. Mutations in hepatocyte nuclear factor-1-beta cause the "renal cysts and diabetes syndrome," isolated renal cystic dysplasia, and a variety of other malformations. Based on its expression pattern and the observation of two affected cases, we propose that haploinsufficiency of hepatocyte nuclear factor-1-beta may be causally related to the production of the prune belly syndrome phenotype through a mechanism of prostatic and ureteral hypoplasia that results in severe obstructive uropathy with urinary tract and abdominal distension. Copyright Thieme Medical Publishers.

  6. Optimization of the isolation and cultivation of Cyprinus carpio primary hepatocytes.

    Science.gov (United States)

    Yanhong, Fan; Chenghua, He; Guofang, Liu; Haibin, Zhang

    2008-10-01

    The aquatic environment is affected by numerous chemical contaminants. There is an increasing need to identify these chemicals and to evaluate their potential toxicity towards aquatic life. In this research we optimized techniques for primary cell culture of Cyprinus carpio hepatocytes as one adjunct model for ecotoxicological evaluation of the potential hazards of xenobiotics in the aquatic environment. In this study, Cyprinus carpio hepatocytes were isolated by mechanical separation, two-step collagenase perfusion, and pancreatin digestion. The hepatocytes or parenchymal cells could be separated from cell debris and from non-parenchymal cells by low-speed centrifugation (Percoll gradient centrifugation). The harvested hepatocytes were suspended in DMEM, M199 (cultured in 5% CO(2)), or L-15 (cultured without 5% CO(2)) medium then cultured at 17, 27, or 37 degrees C. Cell yield was counted by use of a hemocytometer, and the viability of the cells was assessed by use of the Trypan blue exclusion test. Results from these studies showed that the best method of isolation was pancreatin digestion (the cell yield was 2.7 x 10(8) per g (liver weight) and the viability was 98.4%) and the best medium was M199 (cultured in 5% CO(2)) or L-15 (cultured without 5% CO(2)). The optimum culture temperature was 27 degrees C. The primary hepatocytes culture of Cyprimus carpio grew well and satisfied requirements for most toxicological experiments in this condition.

  7. Generation, characterization and potential therapeutic applications of mature and functional hepatocytes from stem cells.

    Science.gov (United States)

    Zhang, Zhenzhen; Liu, Jianfang; Liu, Yang; Li, Zheng; Gao, Wei-Qiang; He, Zuping

    2013-02-01

    Liver cancer is the sixth most common tumor in the world and the majority of patients with this disease usually die within 1 year. The effective treatment for end-stage liver disease (also known as liver failure), including liver cancer or cirrhosis, is liver transplantation. However, there is a severe shortage of liver donors worldwide, which is the major handicap for the treatment of patients with liver failure. Scarcity of liver donors underscores the urgent need of using stem cell therapy to the end-stage liver disease. Notably, hepatocytes have recently been generated from hepatic and extra-hepatic stem cells. We have obtained mature and functional hepatocytes from rat hepatic stem cells. Here, we review the advancements on hepatic differentiation from various stem cells, including hepatic stem cells, embryonic stem cells, the induced pluripotent stem cells, hematopoietic stem cells, mesenchymal stem cells, and probably spermatogonial stem cells. The advantages, disadvantages, and concerns on differentiation of these stem cells into hepatic cells are highlighted. We further address the methodologies, phenotypes, and functional characterization on the differentiation of numerous stem cells into hepatic cells. Differentiation of stem cells into mature and functional hepatocytes, especially from an extra-hepatic stem cell source, would circumvent the scarcity of liver donors and human hepatocytes, and most importantly it would offer an ideal and promising source of hepatocytes for cell therapy and tissue engineering in treating liver disease. Copyright © 2012 Wiley Periodicals, Inc.

  8. Australian Children's Understanding of Display Rules

    Science.gov (United States)

    Choy, Grace

    2009-01-01

    Cultural display rules govern the manifestation of emotional expressions. In compliance with display rules, the facial expressions displayed (i.e. apparent emotion) may be incongruent with the emotion experienced (i.e. real emotion). This study investigates Australian Caucasian children's understanding of display rules. A sample of 80 four year…

  9. The case for transparent depth display

    NARCIS (Netherlands)

    Kooi, F.L.

    2003-01-01

    Purpose: The continuing developments in display technology have resulted in the ability to present increasing amounts of data on computer displays. One of the coming break-throughs is generally believed to be the introduction of '3-D displays': displays with a true sense of depth. Though these types

  10. Whole-body X-irradiation of mice accelerates polyploidization of hepatocytes

    International Nuclear Information System (INIS)

    Shima, A.; Egami, N.

    1985-01-01

    Male C57BL/6 mice were whole-body irradiated with 4.75 gy of X-rays at the age of 2 months and killed at 2, 6, 12 and 19 months after irradiation. The percentage survival began to decline earlier and faster in the irradiated group than the controls up to 19 months after exposure when the study was terminated. The nuclear DNA content of individual hepatocytes was measured by a Feulgen-DNA microfluorometric method, and hepatocytes were classified into various ploidy classes. In the irradiated mice, the degree of polyploidization was significantly higher than the controls by 2 months after exposure and steadily increased up to 6 months after exposure. Thereafter, however, a slow return to the control level was found up to 19 months after irradiation. These results appear to support a hypothesis that radiation accelerates the ageing process as judged from hepatocyte polyploidization. (author)

  11. Preventing hepatocyte oxidative stress cytotoxicity with Mangifera indica L. extract (Vimang).

    Science.gov (United States)

    Remirez, Diadelis; Tafazoli, Shahrzad; Delgado, Rene; Harandi, Asghar A; O'Brien, Peter J

    2005-01-01

    Vimang is an aqueous extract of Mangifera indica used in Cuba to improve the quality of life in patients suffering from inflammatory diseases. In the present study we evaluated the effects of Vimang at preventing reactive oxygen species (ROS) formation and lipid peroxidation in intact isolated rat hepatocytes. Vimang at 20, 50 and 100 microg/ml inhibited hepatocyte ROS formation induced by glucose-glucose oxidase. Hepatocyte cytotoxicity and lipid peroxidation induced by cumene hydroperoxide was also inhibited by Vimang in a dose and time dependent manner at the same concentration. Vimang also inhibited superoxide radical formation by xanthine oxidase and hypoxanthine. The superoxide radical scavenging and antioxidant activity of the Vimang extract was likely related to its gallates, catechins and mangiferin content. To our knowledge, this is the first report of cytoprotective antioxidant effects of Vimang in cellular oxidative stress models.

  12. Choline or methionine reverses impaired secretion of VLDL by hepatocytes from choline-deficient rats

    International Nuclear Information System (INIS)

    Yao, Z.; Vance, D.E.

    1987-01-01

    Male rats fed a choline-deficient (CD) diet for three days accumulated triacylglycerol (TG) in the liver. Hepatocytes from these rats were cultured and maintained in a medium + choline. The rate of secretion of TG was reduced by 50% in the CD cells. Correspondingly, [ 3 H]oleate and [ 3 H]glycerol were incorporated at a 2-fold higher rate into TG secreted by choline-supplemented cells compared to CD cells. Isolation of lipoprotein fractions by ultracentrifugation showed that the reduced secretion of TG by CD hepatocytes was mainly due to an impaired secretion of very low density lipoprotein (VLDL). Incorporation of [ 3 H]leucine into secreted apoB/sub H/, apoB/sub L/ and apoE was markedly reduced in CD cells compared to choline-supplemented cells. Secretion of high density lipoprotein was not reduced in the CD hepatocytes. Normal secretion of VLDL was resumed upon addition of methionine to the CD cells

  13. Lipopolysaccharide impairs hepatocyte ureagenesis from ammonia: involvement of mitochondrial aquaporin-8.

    Science.gov (United States)

    Soria, Leandro R; Marrone, Julieta; Molinas, Sara M; Lehmann, Guillermo L; Calamita, Giuseppe; Marinelli, Raúl A

    2014-05-02

    We recently reported that hepatocyte mitochondrial aquaporin-8 (mtAQP8) channels facilitate the uptake of ammonia and its metabolism into urea. Here we studied the effect of bacterial lipopolysaccharides (LPS) on ammonia-derived ureagenesis. In LPS-treated rats, hepatic mtAQP8 protein expression and diffusional ammonia permeability (measured utilizing ammonia analogues) of liver inner mitochondrial membranes were downregulated. NMR studies using 15N-labeled ammonia indicated that basal and glucagon-induced ureagenesis from ammonia were significantly reduced in hepatocytes from LPS-treated rats. Our data suggest that hepatocyte mtAQP8-mediated ammonia removal via ureagenesis is impaired by LPS, a mechanism potentially relevant to the molecular pathogenesis of defective hepatic ammonia detoxification in sepsis. Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.

  14. Nuclear Medicine Image Display. Chapter 14

    Energy Technology Data Exchange (ETDEWEB)

    Bergmann, H. [Center for Medical Physics and Biomedical Engineering, Medical University of Vienna, Vienna (Austria)

    2014-12-15

    The final step in a medical imaging procedure is to display the image(s) on a suitable display system where it is presented to the medical specialist for diagnostic interpretation. The display of hard copy images on X ray film or photographic film has largely been replaced today by soft copy image display systems with cathode ray tube (CRT) or liquid crystal display (LCD) monitors as the image rendering device. Soft copy display requires a high quality display monitor and a certain amount of image processing to optimize the image both with respect to the properties of the display device and to some psychophysiological properties of the human visual system. A soft copy display system, therefore, consists of a display workstation providing some basic image processing functions and the display monitor as the intrinsic display device. Display devices of lower quality may be used during intermediate steps of the acquisition and analysis of a patient study. Display monitors with a quality suitable for diagnostic reading by the specialist medical doctor are called primary devices, also known as diagnostic devices. Monitors with lower quality but good enough to be used for positioning, processing of studies, presentation of images in the wards, etc. are referred to as secondary devices or clinical devices. Nuclear medicine images can be adequately displayed even for diagnostic purposes on secondary devices. However, the increasing use of X ray images on which to report jointly with images from nuclear medicine studies, such as those generated by dual modality imaging, notably by positron emission tomography (PET)/computed tomography (CT) and single photon emission computed tomography (SPECT)/CT, requires display devices capable of visualizing high resolution grey scale images at diagnostic quality, i.e. primary display devices. Both grey scale and colour display devices are used, the latter playing an important role in the display of processed nuclear medicine images and

  15. Nuclear Medicine Image Display. Chapter 14

    International Nuclear Information System (INIS)

    Bergmann, H.

    2014-01-01

    The final step in a medical imaging procedure is to display the image(s) on a suitable display system where it is presented to the medical specialist for diagnostic interpretation. The display of hard copy images on X ray film or photographic film has largely been replaced today by soft copy image display systems with cathode ray tube (CRT) or liquid crystal display (LCD) monitors as the image rendering device. Soft copy display requires a high quality display monitor and a certain amount of image processing to optimize the image both with respect to the properties of the display device and to some psychophysiological properties of the human visual system. A soft copy display system, therefore, consists of a display workstation providing some basic image processing functions and the display monitor as the intrinsic display device. Display devices of lower quality may be used during intermediate steps of the acquisition and analysis of a patient study. Display monitors with a quality suitable for diagnostic reading by the specialist medical doctor are called primary devices, also known as diagnostic devices. Monitors with lower quality but good enough to be used for positioning, processing of studies, presentation of images in the wards, etc. are referred to as secondary devices or clinical devices. Nuclear medicine images can be adequately displayed even for diagnostic purposes on secondary devices. However, the increasing use of X ray images on which to report jointly with images from nuclear medicine studies, such as those generated by dual modality imaging, notably by positron emission tomography (PET)/computed tomography (CT) and single photon emission computed tomography (SPECT)/CT, requires display devices capable of visualizing high resolution grey scale images at diagnostic quality, i.e. primary display devices. Both grey scale and colour display devices are used, the latter playing an important role in the display of processed nuclear medicine images and

  16. Display of nuclear medicine imaging studies

    International Nuclear Information System (INIS)

    Singh, B.; Kataria, S.K.; Samuel, A.M.

    2002-08-01

    Nuclear medicine imaging studies involve evaluation of a large amount of image data. Digital signal processing techniques have introduced processing algorithms that increase the information content of the display. Nuclear medicine imaging studies require interactive selection of suitable form of display and pre-display processing. Static imaging study requires pre-display processing to detect focal defects. Point operations (histogram modification) along with zoom and capability to display more than one image in one screen is essential. This album mode of display is also applicable to dynamic, MUGA and SPECT data. Isometric display or 3-D graph of the image data is helpful in some cases e.g. point spread function, flood field data. Cine display is used on a sequence of images e.g. dynamic, MUGA and SPECT imaging studies -to assess the spatial movement of tracer with time. Following methods are used at the investigator's discretion for inspection of the 3-D object. 1) Display of orthogonal projections, 2) Display of album of user selected coronal/ sagital/ transverse orthogonal slices, 3) Display of three orthogonal slices through user selected point, 4) Display of a set of orthogonal slices generated in the user-selected volume, 5) Generation and display of 3-D shaded surface. 6) Generation of volume data and display along with the 3-D shaded surface, 7) Side by side display orthogonal slices of two 3-D objects. Displaying a set of two-dimensional slices of a 3-D reconstructed object through shows all the defects but lacks the 3-D perspective. Display of shaded surface lacks the ability to show the embedded defects. Volume display -combining the 3-D surface and gray level volume data is perhaps the best form of display. This report describes these forms of display along with the theory. (author)

  17. Crystallization of hepatocyte nuclear factor 4α (HNF4α) in complex with the HNF1α promoter element

    Energy Technology Data Exchange (ETDEWEB)

    Lu, Peng; Liu, Jianguo; Melikishvili, Manana; Fried, Michael G.; Chi, Young-In, E-mail: ychi@uky.edu [Department of Molecular and Cellular Biochemistry and Center for Structural Biology, University of Kentucky, Lexington, KY 40536 (United States)

    2008-04-01

    Sample preparation, characterization, crystallization and preliminary X-ray analysis are reported for the HNF4α–DNA binary complex. Hepatocyte nuclear factor 4α (HNF4α) is a member of the nuclear receptor superfamily that plays a central role in organ development and metabolic functions. Mutations on HNF4α cause maturity-onset diabetes of the young (MODY), a dominant monogenic cause of diabetes. In order to understand the molecular mechanism of promoter recognition and the molecular basis of disease-causing mutations, the recombinant HNF4α DNA-binding domain was prepared and used in a study of its binding properties and in crystallization with a 21-mer DNA fragment that contains the promoter element of another MODY gene, HNF1α. The HNF4α protein displays a cooperative and specific DNA-binding activity towards its target gene-recognition elements. Crystals of the complex diffract to 2.0 Å using a synchrotron-radiation source under cryogenic (100 K) conditions and belong to space group C2, with unit-cell parameters a = 121.63, b = 35.43, c = 70.99 Å, β = 119.36°. A molecular-replacement solution has been obtained and structure refinement is in progress. This structure and the binding studies will provide the groundwork for detailed functional and biochemical studies of the MODY mutants.

  18. Crystallization of hepatocyte nuclear factor 4α (HNF4α) in complex with the HNF1α promoter element

    International Nuclear Information System (INIS)

    Lu, Peng; Liu, Jianguo; Melikishvili, Manana; Fried, Michael G.; Chi, Young-In

    2008-01-01

    Sample preparation, characterization, crystallization and preliminary X-ray analysis are reported for the HNF4α–DNA binary complex. Hepatocyte nuclear factor 4α (HNF4α) is a member of the nuclear receptor superfamily that plays a central role in organ development and metabolic functions. Mutations on HNF4α cause maturity-onset diabetes of the young (MODY), a dominant monogenic cause of diabetes. In order to understand the molecular mechanism of promoter recognition and the molecular basis of disease-causing mutations, the recombinant HNF4α DNA-binding domain was prepared and used in a study of its binding properties and in crystallization with a 21-mer DNA fragment that contains the promoter element of another MODY gene, HNF1α. The HNF4α protein displays a cooperative and specific DNA-binding activity towards its target gene-recognition elements. Crystals of the complex diffract to 2.0 Å using a synchrotron-radiation source under cryogenic (100 K) conditions and belong to space group C2, with unit-cell parameters a = 121.63, b = 35.43, c = 70.99 Å, β = 119.36°. A molecular-replacement solution has been obtained and structure refinement is in progress. This structure and the binding studies will provide the groundwork for detailed functional and biochemical studies of the MODY mutants

  19. LMDS Lightweight Modular Display System.

    Science.gov (United States)

    1982-02-16

    based on standard functions. This means that the cost to produce a particular display function can be met in the most economical fashion and at the same...not mean that the NTDS interface would be eliminated. What is anticipated is the use of ETHERNET at a low level of system interface, ie internal to...GENERATOR dSYMBOL GEN eCOMMUNICATION 3-2 The architecture of the unit’s (fig 3-4) input circuitry is based on a video table look-up ROM. The function

  20. Displaying Annotations for Digitised Globes

    Science.gov (United States)

    Gede, Mátyás; Farbinger, Anna

    2018-05-01

    Thanks to the efforts of the various globe digitising projects, nowadays there are plenty of old globes that can be examined as 3D models on the computer screen. These globes usually contain a lot of interesting details that an average observer would not entirely discover for the first time. The authors developed a website that can display annotations for such digitised globes. These annotations help observers of the globe to discover all the important, interesting details. Annotations consist of a plain text title, a HTML formatted descriptive text and a corresponding polygon and are stored in KML format. The website is powered by the Cesium virtual globe engine.

  1. DP: Parameter Display Page Program

    International Nuclear Information System (INIS)

    Anderson, M.

    1994-01-01

    The Parameter Display Page program (DP) is a Motif/X11-based program to allow easily configured, dynamic device and process variable monitoring and manipulation in the EPICS environment. DP provides a tabular data format for interactive viewing and manipulation of device and process variable statistics, as well as formatted PostScript output to files and printers. DP understands and operates in two (unfortunately disjoint at this time) namespaces in the EPICS environment ''devices'' and ''process variables''. The higher level namespace of devices includes Composite and Atomic Devices registered via the Device Access server; the lower level (flat) namespace is that of normal Process Variables accessible via Channel Access

  2. Xenobiotic-Metabolizing Enzyme and Transporter Gene Expression in Primary Cultures of Human Hepatocytes Modulated by Toxcast Chemicals

    Science.gov (United States)

    Primary human hepatocyte cultures are useful in vitro model systems of human liver because when cultured under appropriate conditions the hepatocytes retain liver-like functionality such as metabolism, transport, and cell signaling. This model system was used to characterize the ...

  3. Diclofenac inhibits tumor necrosis factor-a-induced nuclear factor-kB activation causing synergic hepatocyte apoptosis

    NARCIS (Netherlands)

    Frederiksson, L; Herpers, B; Benedetti, G; Matadin, Q; Puigvert, J.C.; de Bont, H; Dragovic, S.; Vermeulen, N.P.E.; Commandeur, J.N.M.; Danen, E; de Graauw, M; van de Water, B.

    2011-01-01

    Drug-induced liver injury (DILI) is an important clinical problem. It involves crosstalk between drug toxicity and the immune system, but the exact mechanism at the cellular hepatocyte level is not well understood. Here we studied the mechanism of crosstalk in hepatocyte apoptosis caused by

  4. Induced Mitogenic Activity in AML-12 Mouse Hepatocytes Exposed to Low-dose Ultra-Wideband Electromagnetic Radiation

    Directory of Open Access Journals (Sweden)

    P. B. Tchounwou

    2005-04-01

    Full Text Available Ultra–wideband (UWB technology has increased with the use of various civilian and military applications. In the present study, we hypothesized that low-dose UWB electromagnetic radiation (UWBR could elicit a mitogenic effect in AML-12 mouse hepatocytes, in vitro. To test this hypothesis, we exposed AML-12 mouse hepatocytes, to UWBR in a specially constructed gigahertz transverse electromagnetic mode (GTEM cell. Cells were exposed to UWBR for 2 h at a temperature of 23°C, a pulse width of 10 ns, a repetition rate of 1 kHz, and field strength of 5-20 kV/m. UWB pulses were triggered by an external pulse generator for UWBR exposure but were not triggered for the sham exposure. We performed an MTT Assay to assess cell viability for UWBR-treated and sham-exposed hepatocytes. Data from viability studies indicated a time-related increase in hepatocytes at time intervals from 8-24 h post exposure. UWBR exerted a statistically significant (p < 0.05 dose-dependent response in cell viability in both serum-treated and serum free medium (SFM -treated hepatocytes. Western blot analysis of hepatocyte lysates demonstrated that cyclin A protein was induced in hepatocytes, suggesting that increased MTT activity after UWBR exposure was due to cell proliferation. This study indicates that UWBR has a mitogenic effect on AML-12 mouse hepatocytes and implicates a possible role for UWBR in hepatocarcinoma.

  5. IL-6 modulates hepatocyte proliferation via induction of HGF/p21cip1: Regulation by SOCS3

    International Nuclear Information System (INIS)

    Sun Rui; Jaruga, Barbara; Kulkarni, Shailin; Sun Haoyu; Gao Bin

    2005-01-01

    The precise role of IL-6 in liver regeneration and hepatocyte proliferation is controversial and the role of SOCS3 in liver regeneration remains unknown. Here we show that in vitro treatment with IL-6 inhibited primary mouse hepatocyte proliferation. IL-6 induced p21 cip1 protein expression in primary mouse hepatocytes. Disruption of the p21 cip1 gene abolished the inhibitory effect of IL-6 on cell proliferation. Co-culture with nonparenchymal liver cells diminished IL-6 inhibition of hepatocyte proliferation, which was likely due to IL-6 stimulation of nonparenchymal cells to produce HGF. Finally, IL-6 induced higher levels of p21 cip1 protein expression and a slightly stronger inhibition of cell proliferation in SOCS3 +/- mouse hepatocytes compared to wild-type hepatocytes, while liver regeneration was enhanced and prolonged in SOCS3 +/- mice. Our findings suggest that IL-6 directly inhibits hepatocyte proliferation via a p21 cip1 -dependent mechanism and indirectly enhances hepatocyte proliferation via stimulating nonparenchymal cells to produce HGF. SOCS3 negatively regulates liver regeneration

  6. Palm kernel cake extract exerts hepatoprotective activity in heat-induced oxidative stress in chicken hepatocytes.

    Science.gov (United States)

    Oskoueian, Ehsan; Abdullah, Norhani; Idrus, Zulkifli; Ebrahimi, Mahdi; Goh, Yong Meng; Shakeri, Majid; Oskoueian, Armin

    2014-10-02

    Palm kernel cake (PKC), the most abundant by-product of oil palm industry is believed to contain bioactive compounds with hepatoprotective potential. These compounds may serve as hepatoprotective agents which could help the poultry industry to alleviate adverse effects of heat stress on liver function in chickens. This study was performed to evaluate the hepatoprotective potential of PKC extract in heat-induced oxidative stress in chicken hepatocytes. The nature of the active metabolites and elucidation of the possible mechanism involved were also investigated. The PKC extract possessed free radical scavenging activity with values significantly (p < 0.05) lower than silymarin as the reference antioxidant. Heat-induced oxidative stress in chicken hepatocyte impaired the total protein, lipid peroxidation and antioxidant enzymes activity significantly (p < 0.05). Treatment of heat-induced hepatocytes with PKC extract (125 μg/ml) and silymarin as positive control increased these values significantly (p < 0.05). The real time PCR and western blot analyses revealed the significant (p < 0.05) up-regulation of oxidative stress biomarkers including TNF-like, IFN-γ and IL-1β genes; NF-κB, COX-2, iNOS and Hsp70 proteins expression upon heat stress in chicken hepatocytes. The PKC extract and silymarin were able to alleviate the expression of all of these biomarkers in heat-induced chicken hepatocytes. The gas chromatography-mass spectrometry analysis of PKC extract showed the presence of fatty acids, phenolic compounds, sugar derivatives and other organic compounds such as furfural which could be responsible for the observed hepatoprotective activity. Palm kernel cake extract could be a potential agent to protect hepatocytes function under heat induced oxidative stress.

  7. Assessment of mitochondrial dysfunction-related, drug-induced hepatotoxicity in primary rat hepatocytes

    International Nuclear Information System (INIS)

    Liu, Cong; Sekine, Shuichi; Ito, Kousei

    2016-01-01

    Evidence that mitochondrial dysfunction plays a central role in drug-induced liver injury is rapidly accumulating. In contrast to physiological conditions, in which almost all adenosine triphosphate (ATP) in hepatocytes is generated in mitochondria via aerobic respiration, the high glucose content and limited oxygen supply of conventional culture systems force primary hepatocytes to generate most ATP via cytosolic glycolysis. Thus, such anaerobically poised cells are resistant to xenobiotics that impair mitochondrial function, and are not suitable to identify drugs with mitochondrial liabilities. In this study, primary rat hepatocytes were cultured in galactose-based medium, instead of the conventional glucose-based medium, and in hyperoxia to improve the reliance of energy generation on aerobic respiration. Activation of mitochondria was verified by diminished cellular lactate release and increased oxygen consumption. These conditions improved sensitivity to the mitochondrial complex I inhibitor rotenone. Since oxidative stress is also a general cause of mitochondrial impairment, cells were exposed to test compounds in the presence of transferrin to increase the generation of reactive oxygen species via increased uptake of iron. Finally, 14 compounds with reported mitochondrial liabilities were tested to validate this new drug-induced mitochondrial toxicity assay. Overall, the culture of primary rat hepatocytes in galactose, hyperoxia and transferrin is a useful model for the identification of mitochondrial dysfunction-related drug-induced hepatotoxicity. - Highlights: • Drug-induced mitochondrial toxicity was evaluated using primary rat hepatocytes. • Galactose and hyperoxia could activate OXPHOS in primary rat hepatocytes. • Cells with enhanced OXPHOS exhibit improved sensitivity to mitochondrial toxins. • Transferrin potentiate mitochondrial toxicity via increased ROS production.

  8. Resveratrol Differentially Regulates NAMPT and SIRT1 in Hepatocarcinoma Cells and Primary Human Hepatocytes

    Science.gov (United States)

    Schuster, Susanne; Penke, Melanie; Gorski, Theresa; Petzold-Quinque, Stefanie; Damm, Georg; Gebhardt, Rolf; Kiess, Wieland; Garten, Antje

    2014-01-01

    Resveratrol is reported to possess chemotherapeutic properties in several cancers. In this study, we wanted to investigate the molecular mechanisms of resveratrol-induced cell cycle arrest and apoptosis as well as the impact of resveratrol on NAMPT and SIRT1 protein function and asked whether there are differences in hepatocarcinoma cells (HepG2, Hep3B cells) and non-cancerous primary human hepatocytes. We found a lower basal NAMPT mRNA and protein expression in hepatocarcinoma cells compared to primary hepatocytes. In contrast, SIRT1 was significantly higher expressed in hepatocarcinoma cells than in primary hepatocytes. Resveratrol induced cell cycle arrest in the S- and G2/M- phase and apoptosis was mediated by activation of p53 and caspase-3 in HepG2 cells. In contrast to primary hepatocytes, resveratrol treated HepG2 cells showed a reduction of NAMPT enzymatic activity and increased p53 acetylation (K382). Resveratrol induced NAMPT release from HepG2 cells which was associated with increased NAMPT mRNA expression. This effect was absent in primary hepatocytes where resveratrol was shown to function as NAMPT and SIRT1 activator. SIRT1 inhibition by EX527 resembled resveratrol effects on HepG2 cells. Furthermore, a SIRT1 overexpression significantly decreased both p53 hyperacetylation and resveratrol-induced NAMPT release as well as S-phase arrest in HepG2 cells. We could show that NAMPT and SIRT1 are differentially regulated by resveratrol in hepatocarcinoma cells and primary hepatocytes and that resveratrol did not act as a SIRT1 activator in hepatocarcinoma cells. PMID:24603648

  9. EXPERIMENTAL SUBSTANTIATION OF PERMEABILIZED HEPATOCYTES MODEL FOR INVESTIGATION OF MITOCHONDRIA IN SITU RESPIRATION.

    Science.gov (United States)

    Merlavsky, V M; Manko, B O; Ikkert, O V; Manko, V V

    2015-01-01

    To verify experimentally the model of permeabilized hepatocytes, the degree of cell permeability was assessed using trypan blue and polarographycally determined cell respiration rate upon succinate (0.35 mM) and a-ketoglutarate (1 mM) oxidation. Oxidative phosphorylation was stimulated by ADP (750 μM). Hepatocyte permeabilization depends on digitonin concentraion in medium and on the number of cells in suspension. Thus, the permeabilization of 0.9-1.7 million cells/ml was completed by 25 μg/ml of digitonin, permeabilization of 2.0-3.0 million cells/ml--by 50 μg/ml of digitonin and permeabilization of 4.0-5.6 million cells/ml--by 100 μg/ml. Thus, the higher is the suspension density, the higher digitonin concentration is required. Treatment of hepatocytes with digitonin resulted in a decrease of endogenous respiration rate to a minimum upon 20-22 μg of digitonin per 1 million cells. Supplementation of permeabilized hepatocytes with α-ketoglutarate maintained stable respiration rate, on the level higher than endogenous respiration at the corresponding digitonin concentration, unlike the intact cells. Respiration rate of permeabilized hepatocytes at the simultaneous addition of α-ketoglutarate and ADP increased to the level of intact cell respiration, irrespective of digitonin concentration. Addition of solely succinate and especially succinate plus ADP markedly intensified the respiration of permeabilized hepatocytes to the level higher than that of intact cells. The dependence of succinate-stimulated respiration on digitonin concentration reached maximum at 20-22 αg of digitonin per 1 million cells. Optimal ratio of digitonin amount and the cell number in suspension is expected to be different in various tissues.

  10. Connexin 32 and connexin 43 are involved in lineage restriction of hepatic progenitor cells to hepatocytes

    Directory of Open Access Journals (Sweden)

    Haiyun Pei

    2017-11-01

    Full Text Available Abstract Background Bi-potential hepatic progenitor cells can give rise to both hepatocytes and cholangiocytes, which is the last phase and critical juncture in terms of sequentially hepatic lineage restriction from any kind of stem cells. If their differentiation can be controlled, it might access to functional hepatocytes to develop pharmaceutical and biotechnology industries as well as cell therapies for end-stage liver diseases. Methods In this study, we investigated the influence of Cx32 and Cx43 on hepatocyte differentiation of WB-F344 cells by in vitro gain and loss of function analyses. An inhibitor of Cx32 was also used to make further clarification. To reveal p38 MAPK pathway is closely related to Cxs, rats with 70% partial hepatectomy were injected intraperitoneally with a p38 inhibitor, SB203580. Besides, the effects of p38 MAPK pathway on differentiation of hepatoblasts isolated from fetal rat livers were evaluated by addition of SB203580 in culture medium. Results In vitro gain and loss of function analyses showed overexpression of Connexin 32 and knockdown of Connexin 43 promoted hepatocytes differentiation from hepatic progenitor cells. In addition, in vitro and ex vivo research revealed inhibition of p38 mitogen-activated protein kinase pathway can improve hepatocytes differentiation correlating with upregulation of Connexin 32 expression and downregulation of Connexin 43 expression. Conclusions Here we demonstrate that Connexins play crucial roles in facilitating differentiation of hepatic progenitors. Our work further implicates that regulators of Connexins and their related pathways might provide new insights to improve lineage restriction of stem cells to mature hepatocytes.

  11. Regulation of lipid synthesis in hepatocytes from lean and obese Zucker rats

    International Nuclear Information System (INIS)

    Triscari, J.; Greenwood, M.R.; Sullivan, A.C.

    1981-01-01

    Fatty acid synthesis and CO 2 production were evaluated in hepatocytes from lean and obese Zucker rats in the presence of 3 H 2 O, and several carbon precursors. The incorporation of 3 H 2 O into fatty acids was greater in obese compared to lean rats in both the isolated hepatocyte and in vivo. The rates of incorporation of 3 H 2 O into fatty acids and cholesterol in hepatocytes of both lean and obese rats were linear for 2 hr, in the absence or presence of 16.7 mM glucose. Rates of fatty acid synthesis were higher in the presence of 16.7 mM glucose compared to the absence of glucose in both lean and obese while rates of cholesterol synthesis were similar. The incorporation of 3H2O into fatty acids, but not into cholesterol, was correlated with increasing glucose concentration and was 2 to three-fold higher in hepatocytes of obese compared to lean rats in the presence of several carbon precursors. Differences in CO 2 production between lean and obese rats suggested increased pentose phosphate shunt activity, decreased pyruvate dehydrogenase activity, and lower tricarboxylic acid cycle activity in obese rats. Fatty acid synthesis and CO 2 production from 3 H 2 O and [U- 14 C]glucose in hepatocytes of lean and obese rats was similarly elevated by insulin and depressed by glucagon at several concentrations, suggesting that hepatocytes of obese animals respond to these hormones. These data indicate that rates of hepatic fatty acid synthesis although higher in obese rats respond to modulation in a fashion which is similar to the response in lean rats. The present studies suggest that the oxidation of several carbon precursors in the tricarboxylic acid cycle is diminished in obese compared to lean rats, but pentose phosphate shunt activity is greater in the obese Zucker rats

  12. 3D-printed gelatin scaffolds of differing pore geometry modulate hepatocyte function and gene expression.

    Science.gov (United States)

    Lewis, Phillip L; Green, Richard M; Shah, Ramille N

    2018-03-15

    Three dimensional (3D) printing is highly amenable to the fabrication of tissue-engineered organs of a repetitive microstructure such as the liver. The creation of uniform and geometrically repetitive tissue scaffolds can also allow for the control over cellular aggregation and nutrient diffusion. However, the effect of differing geometries, while controlling for pore size, has yet to be investigated in the context of hepatocyte function. In this study, we show the ability to precisely control pore geometry of 3D-printed gelatin scaffolds. An undifferentiated hepatocyte cell line (HUH7) demonstrated high viability and proliferation when seeded on 3D-printed scaffolds of two different geometries. However, hepatocyte specific functions (albumin secretion, CYP activity, and bile transport) increases in more interconnected 3D-printed gelatin cultures compared to a less interconnected geometry and to 2D controls. Additionally, we also illustrate the disparity between gene expression and protein function in simple 2D culture modes, and that recreation of a physiologically mimetic 3D environment is necessary to induce both expression and function of cultured hepatocytes. Three dimensional (3D) printing provides tissue engineers the ability spatially pattern cells and materials in precise geometries, however the biological effects of scaffold geometry on soft tissues such as the liver have not been rigorously investigated. In this manuscript, we describe a method to 3D print gelatin into well-defined repetitive geometries that show clear differences in biological effects on seeded hepatocytes. We show that a relatively simple and widely used biomaterial, such as gelatin, can significantly modulate biological processes when fabricated into specific 3D geometries. Furthermore, this study expands upon past research into hepatocyte aggregation by demonstrating how it can be manipulated to enhance protein function, and how function and expression may not precisely correlate in

  13. Cell proliferation studies in rodent hepatocytes during 1,4-dichlorobenzene administration

    International Nuclear Information System (INIS)

    Eldridge, S.R.; Tilbury, L.F.; Randall, H.; Goldsworthy, T.L.; Butterworth, B.E.

    1990-01-01

    In the NTP bioassay, 1,4-dichlorobenzene (DCB) induced hepatocellular carcinomas in mice, but not in rats. Because DCB is not DNA reactive, a cell proliferation study under conditions of the bioassay was undertaken to determine whether increased cell proliferation might play a role in DCB-induced hepatocarcinogenicity. DCB was administered in corn oil by gavage at the highest bioassay dose to male B6C3F1 mice (600 mg/kg) and male F344 rats (300 mg/kg) for five consecutive days. Cell proliferation was detected by labeling hepatocytes with either 5-bromo-2'-deoxyuridine (BRDU) or 3 H-thymidine delivered during the entire treatment period by subcutaneously implanted osmotic pumps. An increase in liver weight as a percentage of body weight was observed in treated mice (6.7±0.6 vs. 5.9±0.2) and rats (4.7±0.1 vs. 4.0±0.2) compared to controls. No significant elevations in plasma enzymes were found in either treated species, indicating a lack of overt hepatotoxicity. Histopathological evaluation revealed no evidence of hepatotoxicity in either species. The percentage of hepatocytes in S-phase was increased approximately 10-fold in both treated mice and rats compared to the respective control animals. Mice exhibited a centrilobular pattern of labeled hepatocytes, whereas rat hepatocytes were labeled hepatocytes, whereas rat hepatocytes were labeled throughout the lobules. These data demonstrate the hepatic mitogenic activity of DCB in mice and rats. However, this response dose not correlate with DCB-induced hepatocarcinogenicity. Further studies are required to examine the extent, duration and nature of the proliferative response in order to understand the species-specific effects of DCB

  14. Implications of the simultaneous occurrence of glycolysis and gluconeogenesis in hepatocytes from normal and hyperthyroid rats

    International Nuclear Information System (INIS)

    Phillips, J.W.; Berry, M.N.

    2001-01-01

    The mammalian liver has the capability for both glycolysis and gluconeogenesis. In the fasting state, metabolites such as lactate and glycerol, generated in the peripheral tissues, are taken up by the liver and converted to glucose. However, hepatocytes from fasted animals are also capable of substantial rates of glycolysis. It is generally assumed that glycolysis and gluconeogenesis do not occur simultaneously in the same cell, but rather the metabolic conditions that facilitate flux through one pathway impair flow in the opposite direction. The actual direction of flow at any given moment is thought to be determined by regulatory mechanisms that control flux through the enzymatic steps specific to glycolysis and gluconeogenesis. The rates of glycolysis from [6- 3 H]glucose and gluconeogenesis from [U- 14 C]glycerol were determined in isolated hepatocytes from fasted normal and hyperthyroid rats. We observed that glycolysis from glucose and glucose synthesis from glycerol occurred simultaneously at substantial rates in hepatocytes from normal rats and that gluconeogenesis, but not glycolysis, was increased twofold in hepatocytes from thyroid treated rats. In the hyperthyroid state, the rate of glycolysis from glucose was approximately equal to the rate of glucose formation from glycerol. Hence, metabolism and ATP turnover were stimulated without substantially altering steady-state concentrations of glucose. The concomitant operation of hepatic glycolysis and gluconeogenesis may be a mechanism that accounts in part for the calorigenic effect of thyroid hormone. Since hepatocyles are generally impermeable to phosphorylated metabolites, our observations suggest that glycolysis, and phosphorylation of glycerol take place in the same cells, and that the occurrence of simultaneous glycolysis and gluconeogenesis is an indication of channelling within the hepatocyte cytoplasm of individual hepatocytes

  15. Hepatocyte transplants improve liver function and encephalopathy in portacaval shunted rats.

    Science.gov (United States)

    Fogel, Wieslawa Agnieszka; Stasiak, Anna; Maksymowicz, Michał; Kobos, Jozef; Unzeta, Mercedes; Mussur, Miroslaw

    2014-07-01

    Rats with portacaval shunt (PCS) are useful experimental models of human hepatic encephalopathy in chronic liver dysfunction. We have previously shown that PCS modifies amine neurotransmitter systems in the CNS and increases voluntary alcohol intake by rats. Hepatocyte transplantation, used in acute liver failure, has recently also been applied to chronic liver diseases, which prompted us to investigate whether the altered brain amine system and the drinking behavior in long-term shunted rats could be normalized by hepatocyte transplants. Hepatocytes, isolated from syngeneic donors by collagenase digestion, were injected (3 × 10(6) cells/rat) into the pancreatic tail region, 6 months after PCS. Hepatic function was evaluated by measuring urine urea and plasma L-histidine concentrations. A free choice test with two bottles (tap water and 10% ethyl alcohol) was performed for 3 days to assess the rats' preference for alcohol. The rats were euthanized 2 months posttransplantation. Brain histamine and 5-hydroxyindoleacetic acid (5-HIAA) levels were measured by radioenzymatic assay and by HPLC-EC, respectively, N-tele-methylhistamine by GC/MS while MAOA and MAOB activities by isotopic procedures. Portacaval shunt rats with hepatocyte transplants gave more urea than before transplantation, with lower plasma L-His levels and higher body weight versus the PCS counterparts. Also, those rats consumed less alcohol. The CNS amines and 5-HIAA concentrations, as well as MAO-B activity, being abnormally high in untreated PCS rats, significantly reduced after PCS hepatocyte treatment. The results support the therapeutic values of hepatocyte transplants in chronic liver diseases and the temporary character of PCS-exerted CNS dysfunctions. © 2014 John Wiley & Sons Ltd.

  16. Cytotoxic mechanisms of hydrosulfide anion and cyanide anion in primary rat hepatocyte cultures

    International Nuclear Information System (INIS)

    Thompson, Rodney W.; Valentine, Holly L.; Valentine, William M.

    2003-01-01

    Hydrogen sulfide and hydrogen cyanide are known to compromise mitochondrial respiration through inhibition of cytochrome c oxidase and this is generally considered to be their primary mechanism of toxicity. Experimental studies and the efficiency of current treatment protocols suggest that H 2 S may exert adverse physiological effects through additional mechanisms. To evaluate the role of alternative mechanisms in H 2 S toxicity, the relative contributions of electron transport inhibition, uncoupling of mitochondrial respiration, and opening of the mitochondrial permeability transition pore (MPTP) to hydrosulfide and cyanide anion cytotoxicity in primary hepatocyte cultures were examined. Supplementation of hepatocytes with the glycolytic substrate, fructose, rescued hepatocytes from cyanide anion induced toxicity, whereas fructose supplementation increased hydrosulfide anion toxicity suggesting that hydrosulfide anion may compromise glycolysis in hepatocytes. Although inhibitors of the MPTP opening were protective for hydrosulfide anion, they had no effect on cyanide anion toxicity, consistent with an involvement of the permeability transition pore in hydrosulfide anion toxicity but not cyanide anion toxicity. Exposure of isolated rat liver mitochondria to hydrosulfide did not result in large amplitude swelling suggesting that if H 2 S induces the permeability transition it does so indirectly through a mechanism requiring other cellular components. Hydrosulfide anion did not appear to be an uncoupler of mitochondrial respiration in hepatocytes based upon the inability of oligomycin and fructose to protect hepatocytes from hydrosulfide anion toxicity. These findings support mechanisms additional to inhibition of cytochrome c oxidase in hydrogen sulfide toxicity. Further investigations are required to assess the role of the permeability transition in H 2 S toxicity, determine whether similar affects occur in other cell types or in vivo and evaluate whether this may

  17. Titanium Dioxide Nanoparticles Trigger Loss of Function and Perturbation of Mitochondrial Dynamics in Primary Hepatocytes.

    Directory of Open Access Journals (Sweden)

    Vaishaali Natarajan

    Full Text Available Titanium dioxide (TiO2 nanoparticles are one of the most highly manufactured and employed nanomaterials in the world with applications in copious industrial and consumer products. The liver is a major accumulation site for many nanoparticles, including TiO2, directly through intentional exposure or indirectly through unintentional ingestion via water, food or animals and increased environmental contamination. Growing concerns over the current usage of TiO2 coupled with the lack of mechanistic understanding of its potential health risk is the motivation for this study. Here we determined the toxic effect of three different TiO2 nanoparticles (commercially available rutile, anatase and P25 on primary rat hepatocytes. Specifically, we evaluated events related to hepatocyte functions and mitochondrial dynamics: (1 urea and albumin synthesis using colorimetric and ELISA assays, respectively; (2 redox signaling mechanisms by measuring reactive oxygen species (ROS production, manganese superoxide dismutase (MnSOD activity and mitochondrial membrane potential (MMP; (3 OPA1 and Mfn-1 expression that mediates the mitochondrial dynamics by PCR; and (4 mitochondrial morphology by MitoTracker Green FM staining. All three TiO2 nanoparticles induced a significant loss (p < 0.05 in hepatocyte functions even at concentrations as low as 50 ppm with commercially used P25 causing maximum damage. TiO2 nanoparticles induced a strong oxidative stress in primary hepatocytes. TiO2 nanoparticles exposure also resulted in morphological changes in mitochondria and substantial loss in the fusion process, thus impairing the mitochondrial dynamics. Although this study demonstrated that TiO2 nanoparticles exposure resulted in substantial damage to primary hepatocytes, more in vitro and in vivo studies are required to determine the complete toxicological mechanism in primary hepatocytes and subsequently liver function.

  18. Assessment of mitochondrial dysfunction-related, drug-induced hepatotoxicity in primary rat hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Cong; Sekine, Shuichi, E-mail: ssekine@faculty.chiba-u.jp; Ito, Kousei

    2016-07-01

    Evidence that mitochondrial dysfunction plays a central role in drug-induced liver injury is rapidly accumulating. In contrast to physiological conditions, in which almost all adenosine triphosphate (ATP) in hepatocytes is generated in mitochondria via aerobic respiration, the high glucose content and limited oxygen supply of conventional culture systems force primary hepatocytes to generate most ATP via cytosolic glycolysis. Thus, such anaerobically poised cells are resistant to xenobiotics that impair mitochondrial function, and are not suitable to identify drugs with mitochondrial liabilities. In this study, primary rat hepatocytes were cultured in galactose-based medium, instead of the conventional glucose-based medium, and in hyperoxia to improve the reliance of energy generation on aerobic respiration. Activation of mitochondria was verified by diminished cellular lactate release and increased oxygen consumption. These conditions improved sensitivity to the mitochondrial complex I inhibitor rotenone. Since oxidative stress is also a general cause of mitochondrial impairment, cells were exposed to test compounds in the presence of transferrin to increase the generation of reactive oxygen species via increased uptake of iron. Finally, 14 compounds with reported mitochondrial liabilities were tested to validate this new drug-induced mitochondrial toxicity assay. Overall, the culture of primary rat hepatocytes in galactose, hyperoxia and transferrin is a useful model for the identification of mitochondrial dysfunction-related drug-induced hepatotoxicity. - Highlights: • Drug-induced mitochondrial toxicity was evaluated using primary rat hepatocytes. • Galactose and hyperoxia could activate OXPHOS in primary rat hepatocytes. • Cells with enhanced OXPHOS exhibit improved sensitivity to mitochondrial toxins. • Transferrin potentiate mitochondrial toxicity via increased ROS production.

  19. Resveratrol differentially regulates NAMPT and SIRT1 in Hepatocarcinoma cells and primary human hepatocytes.

    Directory of Open Access Journals (Sweden)

    Susanne Schuster

    Full Text Available Resveratrol is reported to possess chemotherapeutic properties in several cancers. In this study, we wanted to investigate the molecular mechanisms of resveratrol-induced cell cycle arrest and apoptosis as well as the impact of resveratrol on NAMPT and SIRT1 protein function and asked whether there are differences in hepatocarcinoma cells (HepG2, Hep3B cells and non-cancerous primary human hepatocytes. We found a lower basal NAMPT mRNA and protein expression in hepatocarcinoma cells compared to primary hepatocytes. In contrast, SIRT1 was significantly higher expressed in hepatocarcinoma cells than in primary hepatocytes. Resveratrol induced cell cycle arrest in the S- and G2/M- phase and apoptosis was mediated by activation of p53 and caspase-3 in HepG2 cells. In contrast to primary hepatocytes, resveratrol treated HepG2 cells showed a reduction of NAMPT enzymatic activity and increased p53 acetylation (K382. Resveratrol induced NAMPT release from HepG2 cells which was associated with increased NAMPT mRNA expression. This effect was absent in primary hepatocytes where resveratrol was shown to function as NAMPT and SIRT1 activator. SIRT1 inhibition by EX527 resembled resveratrol effects on HepG2 cells. Furthermore, a SIRT1 overexpression significantly decreased both p53 hyperacetylation and resveratrol-induced NAMPT release as well as S-phase arrest in HepG2 cells. We could show that NAMPT and SIRT1 are differentially regulated by resveratrol in hepatocarcinoma cells and primary hepatocytes and that resveratrol did not act as a SIRT1 activator in hepatocarcinoma cells.

  20. Serum Hepatocyte Growth Factor as A Non-Invasive Marker For Evaluation of Hepatocellular Carcinoma

    International Nuclear Information System (INIS)

    Abdelgawad, M.R.; Wahba, M.A.

    2012-01-01

    The change and the prognostic value of serum hepatocyte growth factor and AFP level in patients with cirrhosis and/or primary liver cancer (HCC) were investigated. The level of serum hepatocyte growth factor was determined by using enzyme-linked immunosorbent assay, and AFP was determined by using radioimmunoassay in 29 patients with cirrhosis. Twenty five patients with primary liver cancer (13 patients without nodular cirrhosis and 12 patients with nodular cirrhosis) were categorized according to tumour size (≤ or >5 cm) and the level of AFP (≤ or > 200 ng/dl). The correlation between serum AFP and hepatocyte growth factor were significantly increased (P 0.05). Serum AFP can significantly discriminate between all studied groups (P 0.001) except for the comparison between control and cirrhosis (P>0.05), and also between HCC and HCC without nodular cirrhosis and HCC with cirrhosis (P>0.05). Serum HGF and AFP levels were positively affected by tumour size and nodular cirrhosis (P<0.001). Also, serum HGF level was highly affected by the levels of serum AFP in HCC patients. Non-significant correlation was observed between serum hepatocyte growth factor and AFP in control, cirrhosis, cirrhosis and HCC patients with AFP ? 200 ng/dl. It could be concluded that the over expressions of the hepatocyte growth factor and AFP may indicate an adverse prognosis for patients with cirrhosis and/or liver cancer. The sustained high level of serum hepatocyte growth factor in cirrhosis and/or HCC could be considered a factor related to early tumour diagnosis, so, serum HGF level may be used as a non-invasive marker in diagnosis and prognosis of liver malignancy. However, further studies are highly recommended to evaluate the role of HGF or its constituents in diagnosis and/or therapy in the future in a larger cohort of patients with different stages of liver malignancy

  1. Isolation of Kupffer Cells and Hepatocytes from a Single Mouse Liver

    DEFF Research Database (Denmark)

    Aparicio-Vergara, Marcela; Tencerova, Michaela; Morgantini, Cecilia

    2017-01-01

    Liver perfusion is a common technique used to isolate parenchymal and non-parenchymal liver cells for in vitro experiments. This method allows hepatic cells to be separated based on their size and weight, by centrifugation using a density gradient. To date, other methods allow the isolation of only...... one viable hepatic cellular fraction from a single mouse; either parenchymal (hepatocytes) or non-parenchymal cells (i.e., Kupffer cells or hepatic stellate cells). Here, we describe a method to isolate both hepatocytes and Kupffer cells from a single mouse liver, thereby providing the unique...... advantage of studying different liver cell types that have been isolated from the same organism....

  2. Bidirectional transport of iminodiacetic organic anion analogues between plasma and hepatocyte

    International Nuclear Information System (INIS)

    Peters, A.M.; Myers, M.J.; Mohammadtaghi, S.; Mubashar, M.; Mathie, R.T.

    1998-01-01

    The kinetics of organic anions are well described and back-diffusion from hepatocyte to plasma is accepted. Although iminodiacetic (IDA) analogues, as organic anions, should also show bidirectional transport between hepatocyte and plasma, this has not been directly demonstrated heretofore. The aim of this study was to directly demonstrate back-diffusion and to quantify it in terms of its fractional rate constant. Kinetics of diethyl IDA were studied in three anaesthetised dogs in which femoral arterial and hepatic venous samples were obtained after injection of tracer into (a) a peripheral vein or (b) hepatic artery or portal vein. Arterial time-concentration curves were also compared between peripheral venous and either hepatic arterial or portal venous injections. Time-activity curves were recorded from regions of interest over the cardiac blood pool and peripheral hepatic parenchyma in 30 patients undergoing routine IDA hepatobiliary imaging with diethyl IDA or mebrofenin and fractional rate constants of clearance of IDA from the hepatocyte compared between compartmental and deconvolution analyses. After peripheral injection in dogs, there was an early arteriovenous concentration gradient across the liver indicating an hepatocyte extraction fraction in the three animals of 0.9, 0.8 and 0.6. The net extraction fraction decreased exponentially over 40 min. Time-concentration curves from hepatic vein and femoral artery were virtually superimposed following intrahepatic injections. Peripheral arterial curves, however, had different shapes according to whether injections were intrahepatic or peripheral, and were consistent with significant back-diffusion. In clinical studies, the blood disappearance curves were fitted as the sum of two exponentials and the liver curves as the difference of two exponentials (with rate constants denoted α 1 h and α 2 h ). Based on compartmental analysis of the blood curves, the sum of the fractional rate constants of tracer movement

  3. Evaluation of perfluoroalkyl acid activity using primary mouse and human hepatocytes

    International Nuclear Information System (INIS)

    Rosen, Mitchell B.; Das, Kaberi P.; Wood, Carmen R.; Wolf, Cynthia J.; Abbott, Barbara D.; Lau, Christopher

    2013-01-01

    While perfluorooctanoic acid (PFOA) and perfluorooctane sulfonate (PFOS) have been studied at length, less is known about the biological activity of other perfluoroalkyl acids (PFAAs) detected in the environment. Using a transient transfection assay developed in COS-1 cells, our group has previously evaluated a variety of PFAAs for activity associated with activation of peroxisome proliferator-activated receptor alpha (PPARα). Here we use primary heptatocytes to further assess the biological activity of a similar group of PFAAs using custom designed Taqman Low Density Arrays. Primary mouse and human hepatoyctes were cultured for 48 h in the presence of varying concentrations of 12 different PFAAs or Wy14,643, a known activator of PPARα. Total RNA was collected and the expression of 48 mouse or human genes evaluated. Gene selection was based on either in-house liver microarray data (mouse) or published data using primary hepatocytes (human). Gene expression in primary mouse hepatocytes was more restricted than expected. Genes typically regulated in whole tissue by PPARα agonists were not altered in mouse cells including Acox1, Me1, Acaa1a, Hmgcs1, and Slc27a1. Cyp2b10, a gene regulated by the constitutive androstane receptor and a transcript normally up-regulated by in vivo exposure to PFAAs, was also unchanged in cultured mouse hepatocytes. Cyp4a14, Ehhadh, Pdk4, Cpt1b, and Fabp1 were regulated as expected in mouse cells. A larger group of genes were differentially expressed in human primary hepatocytes, however, little consistency was observed across compounds with respect to which genes produced a significant dose response making the determination of relative biological activity difficult. This likely reflects weaker activation of PPARα in human versus rodent cells as well as variation among individual cell donors. Unlike mouse cells, CYP2B6 was up-regulated in human hepatocytes by a number of PFAAs as was PPARδ. Rankings were conducted on the limited

  4. Effect of UV-B (302 nm) irradiation on isolated rat hepatocytes

    International Nuclear Information System (INIS)

    Lahiri, S.; Habibullah, C.M.; Ayesha, Q.; Khan, A.A.; Srinivas, V.K.; Naithani, R.

    1995-01-01

    The present study aimed to evaluate the effect of UV-B irradiation on the functional integrity, and the metabolic and detoxifying capacity of isolated rat hepatocytes. Isolated rat hepatocytes were irradiated in various doses (400 Jm -2 , 600 Jm -2 , 800 Jm -2 and 1000 Jm -2 ). The cells were assayed for total lactate dehydrogenase, Na + -K + -ATPase, ATPase, ornithine carbamyltransferase activity (OCT) and urea production capacity. Lactate dehydrogenase and Na + -K + -ATPase activity were significantly decreased in all four irradiated groups (P<0.001), whereas viability, OCT and urea production capacity showed no alterations. (au) 22 refs

  5. Comparison of different initiation protocols in the resistant hepatocyte model

    International Nuclear Information System (INIS)

    Espandiari, Parvaneh; Robertson, Larry W.; Srinivasan, Cidambi; Glauert, Howard P.

    2005-01-01

    Several models in rat liver have been developed to study multistage carcinogenesis, including the Solt-Farber resistant hepatocyte model. In this model, initiation consists of either a necrogenic dose of a hepatocarcinogen or a non-necrogenic dose in conjunction with partial hepatectomy (PH). As an alternative to PH, we investigated two different procedures: fasting for 96 h followed by refeeding, or the use of one-day-old neonates. Male Fisher 344 rats were injected p.o. with diethylnitrosamine (DEN) (0, 20, or 100 mg/kg) 24 h after refeeding or PH (controls received DEN alone with no proliferative stimulus). For the neonatal group, male and female Fisher 344 rats were treated with DEN (0 or 20 mg/kg, i.p.) at one day of age. All initiated animals were treated at the same age (11 weeks) with the following selection agents: three daily doses of 2-acetylaminofluorene (AAF) (30 mg/kg), followed by a single dose of carbon tetrachloride (2 ml/kg), followed by three additional daily treatments of AAF (30 mg/kg). Rats were euthanized 2 weeks after the last AAF injection. The PH, neonatal male, and neonatal female groups receiving DEN developed more γ-glutamyl transpeptidase (GGT)-positive foci per cubic centimeter and foci per liver as compared to untreated rats receiving the same proliferative stimulus, whereas the fasting/refeeding group and the group receiving no proliferative stimulus did not. All DEN-treated groups receiving one of the proliferative stimuli had more foci per cubic centimeter than the DEN-treated group receiving no proliferative stimulus. The volume fractions of GGT-positive foci in the PH/DEN and neonatal male/DEN groups were higher than those of both the DEN-treated group receiving no proliferative stimulus and the groups receiving the same proliferative stimulus without DEN. In neonatal females-receiving DEN, the volume fraction was not different from either neonatal females not receiving DEN or DEN-treated rats receiving no proliferative

  6. Nanobody-Displaying Flagellar Nanotubes.

    Science.gov (United States)

    Klein, Ágnes; Kovács, Mátyás; Muskotál, Adél; Jankovics, Hajnalka; Tóth, Balázs; Pósfai, Mihály; Vonderviszt, Ferenc

    2018-02-26

    In this work we addressed the problem how to fabricate self-assembling tubular nanostructures displaying target recognition functionalities. Bacterial flagellar filaments, composed of thousands of flagellin subunits, were used as scaffolds to display single-domain antibodies (nanobodies) on their surface. As a representative example, an anti-GFP nanobody was successfully inserted into the middle part of flagellin replacing the hypervariable surface-exposed D3 domain. A novel procedure was developed to select appropriate linkers required for functional internal insertion. Linkers of various lengths and conformational properties were chosen from a linker database and they were randomly attached to both ends of an anti-GFP nanobody to facilitate insertion. Functional fusion constructs capable of forming filaments on the surface of flagellin-deficient host cells were selected by magnetic microparticles covered by target GFP molecules and appropriate linkers were identified. TEM studies revealed that short filaments of 2-900 nm were formed on the cell surface. ITC and fluorescent measurements demonstrated that the fusion protein exhibited high binding affinity towards GFP. Our approach allows the development of functionalized flagellar nanotubes against a variety of important target molecules offering potential applications in biosensorics and bio-nanotechnology.

  7. Reactor power peaking information display

    International Nuclear Information System (INIS)

    Book, T.L.; Kochendarfer, R.A.

    1986-01-01

    This patent describes a system for monitoring operating conditions within a nuclear reactor. The system consists of a method for measuring the operating parameters within the nuclear reactor, including the position of axial power shaping rods and regulating control rod. It also includes a method for determining from the operating parameters the operating limits before a power peaking condition exists within the nuclear reactor, and a method for displaying the operating limits which consists of a visual display permitting the continuous monitoring of the operating conditions within the nuclear reactor as a graph of the shaping rod position vs the regulating rod position having a permissible area and a restricted area. The permissible area is further divided into a recommended operating area for steady state operation and a cursor located on the graph to indicate the present operating condition of the nuclear reactor to allow an operator to view any need for corrective action based on the movement of the cursor out of the recommended operating area and to take any corrective transient action within the permissible area

  8. Optical display for radar sensing

    Science.gov (United States)

    Szu, Harold; Hsu, Charles; Willey, Jefferson; Landa, Joseph; Hsieh, Minder; Larsen, Louis V.; Krzywicki, Alan T.; Tran, Binh Q.; Hoekstra, Philip; Dillard, John T.; Krapels, Keith A.; Wardlaw, Michael; Chu, Kai-Dee

    2015-05-01

    Boltzmann headstone S = kB Log W turns out to be the Rosette stone for Greek physics translation optical display of the microwave sensing hieroglyphics. The LHS is the molecular entropy S measuring the degree of uniformity scattering off the sensing cross sections. The RHS is the inverse relationship (equation) predicting the Planck radiation spectral distribution parameterized by the Kelvin temperature T. Use is made of the conservation energy law of the heat capacity of Reservoir (RV) change T Δ S = -ΔE equals to the internal energy change of black box (bb) subsystem. Moreover, an irreversible thermodynamics Δ S > 0 for collision mixing toward totally larger uniformity of heat death, asserted by Boltzmann, that derived the so-called Maxwell-Boltzmann canonical probability. Given the zero boundary condition black box, Planck solved a discrete standing wave eigenstates (equation). Together with the canonical partition function (equation) an average ensemble average of all possible internal energy yielded the celebrated Planck radiation spectral (equation) where the density of states (equation). In summary, given the multispectral sensing data (equation), we applied Lagrange Constraint Neural Network (LCNN) to solve the Blind Sources Separation (BSS) for a set of equivalent bb target temperatures. From the measurements of specific value, slopes and shapes we can fit a set of Kelvin temperatures T's for each bb targets. As a result, we could apply the analytical continuation for each entropy sources along the temperature-unique Planck spectral curves always toward the RGB color temperature display for any sensing probing frequency.

  9. Simulated monitor display for CCTV

    International Nuclear Information System (INIS)

    Steele, B.J.

    1982-01-01

    Two computer programs have been developed which generate a two-dimensional graphic perspective of the video output produced by a Closed Circuit Television (CCTV) camera. Both programs were primarily written to produce a graphic display simulating the field-of-view (FOV) of a perimeter assessment system as seen on a CCTV monitor. The original program was developed for use on a Tektronix 4054 desktop computer; however, the usefulness of this graphic display program led to the development of a similar program for a Hewlett-Packard 9845B desktop computer. After entry of various input parameters, such as, camera lens and orientation, the programs automatically calculate and graphically plot the locations of various items, e.g., fences, an assessment zone, running men, and intrusion detection sensors. Numerous special effects can be generated to simulate such things as roads, interior walls, or sides of buildings. Other objects can be digitized and entered into permanent memory similar to the running men. With this type of simulated monitor perspective, proposed camera locations with respect to fences and a particular assessment zone can be rapidly evaluated without the costly time delays and expenditures associated with field evaluation

  10. Non-viral ex vivo hepatic gene transfer by in situ lipofection of liver and intraperitoneal transplantation of hepatocytes.

    Science.gov (United States)

    Rangarajan, P N; Vatsala, P G; Ashok, M S; Srinivas, V K; Habibullah, C M; Padmanaban, G

    1997-04-29

    Perfusion of liver with plasmid DNA-lipofectin complexes via the portal vein results in efficient accumulation of the vector in hepatocytes. Such hepatocytes, when administered intraperitoneally into a hepatectomized rat, repopulate the liver and express the transgene efficiently. This procedure obviates the need for large-scale hepatocyte culture for ex vivo gene transfer. Further, intraperitoneal transplantation is a simple and cost-effective strategy of introducing genetically modified hepatocytes into liver. Thus, in situ lipofection of liver and intraperitoneal transfer of hepatocytes can be developed into a novel method of non-viral ex vivo gene transfer technique that has applications in the treatment of metabolic disorders of liver and hepatic gene therapy.

  11. Magentic Cell labeling of primary and stem cell-derived pig hepatocytes for MRI-based cell tracking of heptocytes transplantation

    Science.gov (United States)

    Pig hepatocytes are an important investigational tool for optimizing hepatocyte transplantation schemes in both allogeneic and xenogeneic transplant scenarios. MRI can be used to serially monitor the transplanted cells, but only if the hepatocytes can be labeled with a magnetic particle. In this wo...

  12. Effects of clofibric acid on mRNA expression profiles in primary cultures of rat, mouse and human hepatocytes

    International Nuclear Information System (INIS)

    Richert, Lysiane; Lamboley, Christelle; Viollon-Abadie, Catherine; Grass, Peter; Hartmann, Nicole; Laurent, Stephane; Heyd, Bruno; Mantion, Georges; Chibout, Salah-Dine; Staedtler, Frank

    2003-01-01

    The mRNA expression profile in control and clofibric acid (CLO)-treated mouse, rat, and human hepatocytes was analyzed using species-specific oligonucleotide DNA microarrays (Affymetrix). A statistical empirical Bayes procedure was applied in order to select the significantly differentially expressed genes. Treatment with the peroxisome proliferator CLO induced up-regulation of genes involved in peroxisome proliferation and in cell proliferation as well as down-regulation of genes involved in apoptosis in hepatocytes of rodent but not of human origin. CLO treatment induced up-regulation of microsomal cytochrome P450 4a genes in rodent hepatocytes and in two of six human hepatocyte cultures. In addition, genes encoding phenobarbital-inducible cytochrome P450s were also up-regulated by CLO in rodent and human hepatocyte cultures. Up-regulation of phenobarbital-inducible UDP-glucuronosyl-transferase genes by CLO was observed in both rat and human but not in mouse hepatocytes. CLO treatment induced up-regulation of L-fatty acid binding protein (L-FABP) gene in hepatocytes of both rodent and human origin. However, while genes of the cytosolic, microsomal, and mitochondrial pathways involved in fatty acid transport and metabolism were up-regulated by CLO in both rodent and human hepatocyte cultures, genes of the peroxisomal pathway of lipid metabolism were up-regulated in rodents only. An up-regulation of hepatocyte nuclear factor 1α (HNF1α) by CLO was observed only in human hepatocyte cultures, suggesting that this trans-activating factor may play a key role in the regulation of fatty acid metabolism in human liver as well as in the nonresponsiveness of human liver to CLO-induced regulation of cell proliferation and apoptosis

  13. Micropatterned co-culture of hepatocyte spheroids layered on non-parenchymal cells to understand heterotypic cellular interactions

    International Nuclear Information System (INIS)

    Otsuka, Hidenori; Sasaki, Kohei; Okimura, Saya; Nagamura, Masako; Nakasone, Yuichi

    2013-01-01

    Microfabrication and micropatterning techniques in tissue engineering offer great potential for creating and controlling cellular microenvironments including cell–matrix interactions, soluble stimuli and cell–cell interactions. Here, we present a novel approach to generate layered patterning of hepatocyte spheroids on micropatterned non-parenchymal feeder cells using microfabricated poly(ethylene glycol) (PEG) hydrogels. Micropatterned PEG-hydrogel-treated substrates with two-dimensional arrays of gelatin circular domains (ϕ = 100 μm) were prepared by photolithographic method. Only on the critical structure of PEG hydrogel with perfect protein rejection, hepatocytes were co-cultured with non-parenchymal cells to be led to enhanced hepatocyte functions. Then, we investigated the mechanism of the functional enhancement in co-culture with respect to the contributions of soluble factors and direct cell–cell interactions. In particular, to elucidate the influence of soluble factors on hepatocyte function, hepatocyte spheroids underlaid with fibroblasts (NIH/3T3 mouse fibroblasts) or endothelial cells (BAECs: bovine aortic endothelial cells) were compared with physically separated co-culture of hepatocyte monospheroids with NIH3T3 or BAEC using trans-well culture systems. Our results suggested that direct heterotypic cell-to-cell contact and soluble factors, both of these between hepatocytes and fibroblasts, significantly enhanced hepatocyte functions. In contrast, direct heterotypic cell-to-cell contact between hepatocytes and endothelial cells only contributed to enhance hepatocyte functions. This patterning technique can be a useful experimental tool for applications in basic science, drug screening and tissue engineering, as well as in the design of artificial liver devices. (paper)

  14. Effects of clofibric acid on mRNA expression profiles in primary cultures of rat, mouse and human hepatocytes.

    Science.gov (United States)

    Richert, Lysiane; Lamboley, Christelle; Viollon-Abadie, Catherine; Grass, Peter; Hartmann, Nicole; Laurent, Stephane; Heyd, Bruno; Mantion, Georges; Chibout, Salah-Dine; Staedtler, Frank

    2003-09-01

    The mRNA expression profile in control and clofibric acid (CLO)-treated mouse, rat, and human hepatocytes was analyzed using species-specific oligonucleotide DNA microarrays (Affymetrix). A statistical empirical Bayes procedure was applied in order to select the significantly differentially expressed genes. Treatment with the peroxisome proliferator CLO induced up-regulation of genes involved in peroxisome proliferation and in cell proliferation as well as down-regulation of genes involved in apoptosis in hepatocytes of rodent but not of human origin. CLO treatment induced up-regulation of microsomal cytochrome P450 4a genes in rodent hepatocytes and in two of six human hepatocyte cultures. In addition, genes encoding phenobarbital-inducible cytochrome P450s were also up-regulated by CLO in rodent and human hepatocyte cultures. Up-regulation of phenobarbital-inducible UDP-glucuronosyl-transferase genes by CLO was observed in both rat and human but not in mouse hepatocytes. CLO treatment induced up-regulation of L-fatty acid binding protein (L-FABP) gene in hepatocytes of both rodent and human origin. However, while genes of the cytosolic, microsomal, and mitochondrial pathways involved in fatty acid transport and metabolism were up-regulated by CLO in both rodent and human hepatocyte cultures, genes of the peroxisomal pathway of lipid metabolism were up-regulated in rodents only. An up-regulation of hepatocyte nuclear factor 1alpha (HNF1alpha) by CLO was observed only in human hepatocyte cultures, suggesting that this trans-activating factor may play a key role in the regulation of fatty acid metabolism in human liver as well as in the nonresponsiveness of human liver to CLO-induced regulation of cell proliferation and apoptosis.

  15. Clinical value of hemoglobin and its association with hepatocyte steatosis in chronic hepatitis B patients

    Directory of Open Access Journals (Sweden)

    WANG Peng

    2017-07-01

    Full Text Available :ObjectiveTo investigate the clinical value of hemoglobin and its association with hepatocyte steatosis in chronic hepatitis B (CHB patients. MethodsA retrospective analysis was performed for the clinical and pathological data of 1580 CHB patients who were hospitalized in The First People′s Hospital of Shunde from January 2006 to December 2014 and underwent liver biopsy, among whom 216 (13.67% had hepatocyte steatosis (hepatocyte steatosis group and 1364 had no hepatocyte steatosis (non-hepatocyte steatosis group. The patients were divided into groups 1, 2, and 3 according to hemoglobin level, and the clinical and pathological features were analyzed and compared between the three groups. The t-test was used for comparison of continuous data between group; a one-way analysis of variance was used for comparision between multiple groups. The Mann-Whitney U test was used for ranked data between groups. The Kruskal-wallis H test was used for ranked data between multiple groups; the chi-square test was used for comparison of categorical data between groups. Spearman correlation analysis was also performed to determine the correlation between two variables. Univariate logistic regression analysis and multivariate stepwise regression analysis were used to identify the influencing factors for hepatocyte steatosis. ResultsBody mass index (BMI, systolic pressure, diastolic pressure, uric acid, total cholesterol, low-density lipoprotein, and HBV DNA load increased with the increase in hemoglobin level (F=12718,3024,4026,4624,38276,28108,7358, all P<0.05. The incidence rates of hepatocyte steatosis in groups 1, 2, and 3 were 7.59%, 1176%,and 21.67%, respectively (χ2=44.23, P<0.05. Hemoglobin was positively correlated with hepatic steatosis (rs=0.211, P<0001. The multivariate logistic regression analysis showed that hemoglobin (odds ratio [OR]=1.066, P<0.05, BMI (OR=1576, P<005, age (OR=1.041, P<0.05, sex

  16. Simulator scene display evaluation device

    Science.gov (United States)

    Haines, R. F. (Inventor)

    1986-01-01

    An apparatus for aligning and calibrating scene displays in an aircraft simulator has a base on which all of the instruments for the aligning and calibrating are mounted. Laser directs beam at double right prism which is attached to pivoting support on base. The pivot point of the prism is located at the design eye point (DEP) of simulator during the aligning and calibrating. The objective lens in the base is movable on a track to follow the laser beam at different angles within the field of vision at the DEP. An eyepiece and a precision diopter are movable into a position behind the prism during the scene evaluation. A photometer or illuminometer is pivotable about the pivot into and out of position behind the eyepiece.

  17. Minimalism context-aware displays.

    Science.gov (United States)

    Cai, Yang

    2004-12-01

    Despite the rapid development of cyber technologies, today we still have very limited attention and communication bandwidth to process the increasing information flow. The goal of the study is to develop a context-aware filter to match the information load with particular needs and capacities. The functions include bandwidth-resolution trade-off and user context modeling. From the empirical lab studies, it is found that the resolution of images can be reduced in order of magnitude if the viewer knows that he/she is looking for particular features. The adaptive display queue is optimized with real-time operational conditions and user's inquiry history. Instead of measuring operator's behavior directly, ubiquitous computing models are developed to anticipate user's behavior from the operational environment data. A case study of the video stream monitoring for transit security is discussed in the paper. In addition, the author addresses the future direction of coherent human-machine vision systems.

  18. X-Windows Widget for Image Display

    Science.gov (United States)

    Deen, Robert G.

    2011-01-01

    XvicImage is a high-performance XWindows (Motif-compliant) user interface widget for displaying images. It handles all aspects of low-level image display. The fully Motif-compliant image display widget handles the following tasks: (1) Image display, including dithering as needed (2) Zoom (3) Pan (4) Stretch (contrast enhancement, via lookup table) (5) Display of single-band or color data (6) Display of non-byte data (ints, floats) (7) Pseudocolor display (8) Full overlay support (drawing graphics on image) (9) Mouse-based panning (10) Cursor handling, shaping, and planting (disconnecting cursor from mouse) (11) Support for all user interaction events (passed to application) (12) Background loading and display of images (doesn't freeze the GUI) (13) Tiling of images.

  19. Consortium for military LCD display procurement

    Science.gov (United States)

    Echols, Gregg

    2002-08-01

    International Display Consortium (IDC) is the joining together of display companies to combined their buying power and obtained favorable terms with a major LCD manufacturer. Consolidating the buying power and grouping the demand enables the rugged display industry of avionics, ground vehicles, and ship based display manufacturers to have unencumbered access to high performance AMLCDs while greatly reducing risk and lowering cost. With an unrestricted supply of AMLCD displays, the consortium members have total control of their risk, cost, deliveries and added value partners. Every display manufacturer desires a very close relationship with a display vender. With IDC each consortium member achieves a close relationship. Consortium members enjoy cost effective access to high performance, industry standard sized LCD panels, and modified commercial displays with 100 degree C clearing points and portrait configurations. Consortium members also enjoy proposal support, technical support and long-term support.

  20. Dimensions of Situatedness for Digital Public Displays

    Directory of Open Access Journals (Sweden)

    Rui José

    2014-01-01

    Full Text Available Public displays are often strongly situated signs deeply embedded in their physical, social, and cultural setting. Understanding how the display is coupled with on-going situations, its level of situatedness, provides a key element for the interpretation of the displays themselves but is also an element for the interpretation of place, its situated practices, and its social context. Most digital displays, however, do not achieve the same sense of situatedness that seems so natural in their nondigital counterparts. This paper investigates people’s perception of situatedness when considering the connection between public displays and their context. We have collected over 300 photos of displays and conducted a set of analysis tasks involving focus groups and structured interviews with 15 participants. The contribution is a consolidated list of situatedness dimensions that should provide a valuable resource for reasoning about situatedness in digital displays and informing the design and development of display systems.

  1. Ferritin expression in rat hepatocytes and Kupffer cells after lead nitrate treatment.

    Science.gov (United States)

    Fan, Yang; Yamada, Toshiyuki; Shimizu, Takeshi; Nanashima, Naoki; Akita, Miki; Suto, Kohji; Tsuchida, Shigeki

    2009-02-01

    Lead nitrate induces hepatocyte proliferation and subsequent apoptosis in rat livers. Iron is a constituent of heme and is also required for cell proliferation. In this study, the expression of ferritin light-chain (FTL), the major iron storage protein, was investigated in rat livers after a single intravenous injection of lead nitrate. Western blotting and immunohistochemistry revealed that FTL was increased in hepatocytes around the central veins and strongly expressed in nonparenchymal cells. Some FTL-positive nonparenchymal cells were identified as Kupffer cells that were positive for CD68. FTL-positive Kupffer cells occupied about 60% of CD68-positive cells in the periportal and perivenous areas. The relationships between FTL expression and apoptosis induction or the engulfment of apoptotic cells were examined. TUNEL-positive cells were increased in the treatment group, and enhanced expression of milk fat globule EGF-like 8 was demonstrated in some Kupffer cells and hepatocytes, indicating enhanced apoptosis induction and phagocytosis of apoptotic cells. FTL-positive Kupffer cells were not detected without lead nitrate treatment or in rat livers treated with clofibrate, which induces hepatocyte proliferation but not apoptosis. These results suggest that FTL expression in Kupffer cells after lead treatment is dependent on phagocytosis of apoptotic cells.

  2. Bone morphogenetic protein-2 is a negative regulator of hepatocyte proliferation downregulated in the regenerating liver

    NARCIS (Netherlands)

    Xu, Cui-Ping; Ji, Wen-Min; van den Brink, Gijs R.; Peppelenbosch, Maikel P.

    2006-01-01

    To characterize the expression and dynamic changes of bone morphogenetic protein (BMP)-2 in hepatocytes in the regenerating liver in rats after partial hepatectomy (PH), and examine the effects of BMP-2 on proliferation of human Huh7 hepatoma cells. Fifty-four adult male Wistar rats were randomly

  3. Bone morphogenetic protein-2 is a negative regulator of hepatocyte proliferation downregulated in the regenerating liver

    NARCIS (Netherlands)

    Xu, Cui-Ping; Ji, Wen-Min; van den Brink, Gijs R.; Peppelenbosch, Maikel P.

    2006-01-01

    AIM: To characterize the expression and dynamic changes of bone morphogenetic protein (BMP)-2 in hepatocytes in the regenerating liver in rats after partial hepatectomy (PH), and examine the effects of BMP-2 on proliferation of human Huh7 hepatoma cells. METHODS: Fifty-four adult male Wistar rats

  4. HUMAN LIVER SLICES EXPRESS THE SAME LIDOCAINE BIOTRANSFORMATION RATE AS ISOLATED HUMAN HEPATOCYTES

    NARCIS (Netherlands)

    OLINGA, P; MEIJER, DKF; SLOOFF, MJH; GROOTHUIS, GMM; Merema, M.T.

    1993-01-01

    In order to investigate whether liver slices are a valuable tool for the assessment of drug metabolism in human liver, we compared the phase I metabolism of lidocaine in human liver slices and hepatocytes prepared from three human livers. Lidocaine is mainly metabolised to monoethylglycinexylidide

  5. Hepatocyte CD81 is required for Plasmodium falciparum and Plasmodium yoelii sporozoite infectivity.

    NARCIS (Netherlands)

    Silvie, O.; Rubinstein, E.; Franetich, J.F.; Prenant, M.; Belnoue, E.; Renia, L.; Hannoun, L.; Eling, W.M.C.; Levy, S.; Boucheix, C.; Mazier, D.

    2003-01-01

    Plasmodium sporozoites are transmitted through the bite of infected mosquitoes and first invade the liver of the mammalian host, as an obligatory step of the life cycle of the malaria parasite. Within hepatocytes, Plasmodium sporozoites reside in a membrane-bound vacuole, where they differentiate

  6. Comparison of trout hepatocytes and liver S9 fractions as in ...

    Science.gov (United States)

    Isolated hepatocytes and liver S9 fractions have been used to collect in vitro biotransformation data for fish as a means of improving modeled estimates of chemical bioaccumulation. To date, however, there have been few direct comparisons of these two methods. In the present study, cryopreserved trout hepatocytes were used to measure in vitro intrinsic clearance rates for 6 polycyclic aromatic hydrocarbons (PAHs). These rates were extrapolated to estimates of in vivo intrinsic clearance and used as inputs to a well-stirred liver model to predict hepatic clearance. Predicted rates of hepatic clearance were then evaluated by comparison to measured rates determined previously using isolated perfused livers. Hepatic clearance rates predicted using hepatocytes were in good agreement with measured values (fractions. For one compound (benzo[a]pyrene), the in vivo intrinsic clearance rate calculated using S9 data was 10-fold higher than that determined using hepatocytes, possibly due to a diffusion limitation on cellular uptake. Generally, however, there was good agreement between calculated in vivo intrinsic clearance rates obtained using either in vitro test system. These results suggest that both systems can be used to improve

  7. Metformin protects primary rat hepatocytes against oxidative stress-induced apoptosis

    NARCIS (Netherlands)

    Conde de la Rosa, Laura; Vrenken, Titia E; Buist-Homan, Manon; Faber, Klaas Nico; Moshage, Han

    The majority of chronic liver diseases are accompanied by oxidative stress, which induces apoptosis in hepatocytes and liver injury. Recent studies suggest that oxidative stress and insulin resistance are important in the pathogenesis of nonalcoholic fatty liver disease (NAFLD) and the

  8. Retroviral-mediated gene transfer and expression of human phenylalanine hydroxylase in primary mouse hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Peng, H.; Armentano, D.; Mackenzie-Graham, L.; Shen, R.F.; Darlington, G.; Ledley, F.D.; Woo, S.L.C. (Baylor College of Medicine, Houston, TX (USA))

    1988-11-01

    Genetic therapy for phenylketonuria (severe phenylalanine hydroxylase deficiency) may require introduction of a normal phenylalanine hydroxylase gene into hepatic cells of patients. The authors report development of a recombinant retrovirus based on the N2 vector for gene transfer and expression of human phenylalanine hydroxylase cDNA in primary mouse hepatocytes. This construct contains an internal promoter of the human {alpha}{sub 1}-antitrypsin gene driving transcription of the phenylalanine hydroxylase cDNA. Primary mouse hepatocytes were isolated from newborn mice, infected with the recombinant virus, and selected for expression of the neomycin-resistance gene. Hepatocytes transformed with the recombinant virus contained high levels of human phenylalanine hydroxylase mRNA transcripts originating from the retroviral and internal promoters. These results demonstrate that the transcriptional regulatory elements of the {alpha}{sub 1} antitrypsin gene retain their tissue-specific function in the recombinant provirus and establish a method for efficient transfer and high-level expression of human phenylalanine hydroxylase in primary hepatocytes.

  9. Retroviral-mediated gene transfer and expression of human phenylalanine hydroxylase in primary mouse hepatocytes

    International Nuclear Information System (INIS)

    Peng, H.; Armentano, D.; Mackenzie-Graham, L.; Shen, R.F.; Darlington, G.; Ledley, F.D.; Woo, S.L.C.

    1988-01-01

    Genetic therapy for phenylketonuria (severe phenylalanine hydroxylase deficiency) may require introduction of a normal phenylalanine hydroxylase gene into hepatic cells of patients. The authors report development of a recombinant retrovirus based on the N2 vector for gene transfer and expression of human phenylalanine hydroxylase cDNA in primary mouse hepatocytes. This construct contains an internal promoter of the human α 1 -antitrypsin gene driving transcription of the phenylalanine hydroxylase cDNA. Primary mouse hepatocytes were isolated from newborn mice, infected with the recombinant virus, and selected for expression of the neomycin-resistance gene. Hepatocytes transformed with the recombinant virus contained high levels of human phenylalanine hydroxylase mRNA transcripts originating from the retroviral and internal promoters. These results demonstrate that the transcriptional regulatory elements of the α 1 antitrypsin gene retain their tissue-specific function in the recombinant provirus and establish a method for efficient transfer and high-level expression of human phenylalanine hydroxylase in primary hepatocytes

  10. Relations between fatty acid synthesis, pyruvate concentration and cell concentration of suspensions of isolated rat hepatocytes

    NARCIS (Netherlands)

    Beynen, A.C.; Geelen, M.J.H.

    1984-01-01

    1. 1. The cell concentration of suspensions of isolated rat hepatocytes affects both the rate of pyruvate accumulation in the incubation medium and the rate of fatty acid synthesis. 2. 2. At low cell concentrations pyruvate accumulation is directly related to the cell concentration but levels off

  11. Interleukin 6 regulates metallothionein gene expression and zinc metabolism in hepatocyte monolayer cultures

    International Nuclear Information System (INIS)

    Schroeder, J.J.; Cousins, R.J.

    1990-01-01

    Attention has focused on the cytokine interleukin 6 (IL-6) as a major mediator of acute-phase protein synthesis in hepatocytes in response to infection and tissue injury. The authors have evaluated the effects of IL-6 and IL-1α as well as extracellular zinc and glucocorticoid hormone on metal-lothionein gene expression and cellular zinc accumulation in rat hepatocyte monolayer cultures. Further, they have evaluated the teleological basis for cytokine mediation by examining cyto-protection from CCl 4 -induced damage. Incubation of hepatocytes with IL-6 led to concentration-dependent and time-dependent increases in metallothionein-1 and -2 mRNA and metallothionein protein. The level of each was increased within 3 hr after the addition of IL-6 at 10 ng/ml. Maximal increases the metallothionein mRNA and metallothionein protein were achieved after 12 hr and 36 hr, respectively. Concomitant with the up-regulation of metallothionein gene expression, IL-6 also increased cellular zinc. Responses to IL-6 required the synthetic glucocorticoid hormone dexamethasone and were optimized by increased extracellular zinc. Thus, IL-6 is a major cytokine mediator of metallothionein gene expression and zinc metabolism in hepatocytes and provides cytoprotection from CCl 4 -induced hepatotoxicity via a mode consistent with dependence upon increased cellular metallothionein synthesis and zinc accumulation

  12. Impairment of mitochondrial function of rat hepatocytes by high fat diet and oxidative stress

    Czech Academy of Sciences Publication Activity Database

    Garnol, T.; Endlicher, R.; Kučera, O.; Drahota, Zdeněk; Červinková, Z.

    2014-01-01

    Roč. 63, č. 2 (2014), s. 271-274 ISSN 0862-8408 R&D Projects: GA MŠk(CZ) LL1204 Grant - others:Univerzita Karlova(CZ) PRVOUK P37/02 Institutional support: RVO:67985823 Keywords : hepatocytes * high fat diet * mitochondrial activities * ROS Subject RIV: ED - Physiology Impact factor: 1.293, year: 2014

  13. Development of MAPC derived induced endodermal progenitors : Generation of pancreatic beta cells and hepatocytes

    NARCIS (Netherlands)

    Sambathkumar, Rangarajan

    2017-01-01

    Multipotent Adult Progenitor Cells (MAPCs) are one potential stem cell source to generate functional hepatocytes or β-cells. However, human MAPCs have less plasticity than pluripotent stem cells (PSCs), as their ability to generate endodermal cells is not robust. Here we studied the role of 14

  14. Impaired mitochondrial metabolism and protein synthesis in streptozotocin diabetic rat hepatocytes

    International Nuclear Information System (INIS)

    Memon, R.A.; Bessman, S.P.; Mohan, C.

    1990-01-01

    Isolated hepatocytes prepared from control, streptozotocin diabetic rats were incubated at 30 degrees C in Krebs-Henseleit bicarbonate buffer, pH 7.4, containing 0.5 mM concentration of each of the 20 natural amino acids. Effect of insulin on the oxidation of 2,3- 14 C and 1,4- 14 C succinate (suc) carbons and their incorporation into hepatocyte protein, lipid and various metabolic intermediates was studied. Mitochondrial oxidation of suc carbons and their incorporation into protein and lipid was significantly lower in diabetic and insulin treated diabetic rats. Diabetic rats failed to exhibit any significant insulin effect on the oxidation of either 2,3 or 1,4- 14 C suc carbons. Amphibolic channeling of 2,3- 14 C suc carbons into amino acids was significantly reduced in hepatocytes of diabetic rats, however, more of these carbons were diverted into the gluconeogenesis pathway. Diabetes caused a far greater decrease in the oxidation of 2,3- 14 C suc carbons as compared to 1,4- 14 C suc. Based on an earlier report that insulin stimulates only the intramitochondrial Krebs cycle reactions, the authors conclude that the diminished level of anabolic activities in the diabetic rat hepatocytes is due to the subsequent reduction in amphibolic channeling of metabolic intermediates

  15. Effects of dehydroepiandrosterone (DHEA) on glucose metabolism in isolated hepatocytes from Zucker rats

    International Nuclear Information System (INIS)

    Finan, A.; Cleary, M.P.

    1986-01-01

    DHEA has been shown to competitively inhibit the pentose phosphate shunt (PPS) enzyme glucose-6-phosphate dehydrogenase (G6PD) when added in vitro to supernatants or homogenates prepared from mammalian tissues. However, no consistent effect on G6PD activity has been determined in tissue removed from DHEA-treated rats. To explore the effects of DHEA on PPS, glucose utilization was measured in hepatocytes from lean and obese male Zucker rats (8 wks of age) following 1 wk of DHEA treatment (0.6% in diet). Incubation of isolated hepatocytes from treated lean Zucker rats with either [1- 14 C] glucose or [6- 14 C] glucose resulted in significant decreases in CO 2 production and total glucose utilization. DHEA-lean rats also had lowered fat pad weights. In obese rats, there was no effect of 1 wk of treatment on either glucose metabolism or fat pad weight. The calculated percent contribution of the PPS to glucose metabolism in hepatocytes was not changed for either DHEA-lean or obese rats when compared to control rats. In conclusion, 1 wk of DHEA treatment lowered overall glucose metabolism in hepatocytes of lean Zucker rats, but did not selectively affect the PPS. The lack of an effect of short-term treatment in obese rats may be due to differences in their metabolism or storage/release of DHEA in tissues in comparison to lean rats

  16. Proteomic Characterization of Primary Mouse Hepatocytes in Collagen Monolayer and Sandwich Culture.

    Science.gov (United States)

    Orsini, Malina; Sperber, Saskia; Noor, Fozia; Hoffmann, Esther; Weber, Susanne N; Hall, Rabea A; Lammert, Frank; Heinzle, Elmar

    2018-01-01

    Dedifferentiation of primary hepatocytes in vitro makes their application in long-term studies difficult. Embedding hepatocytes in a sandwich of extracellular matrix is reported to delay the dedifferentiation process to some extent. In this study, we compared the intracellular proteome of primary mouse hepatocytes (PMH) in conventional monolayer cultures (ML) to collagen sandwich culture (SW) after 1 day and 5 days of cultivation. Quantitative proteome analysis of PMH showed no differences between collagen SW and ML cultures after 1 day. Glycolysis and gluconeogenesis were strongly affected by long-term cultivation in both ML and SW cultures. Interestingly, culture conditions had no effect on cellular lipid metabolism. After 5 days, PMH in collagen SW and ML cultures exhibit characteristic indications of oxidative stress. However, in the SW culture the defense system against oxidative stress is significantly up-regulated to deal with this, whereas in the ML culture a down-regulation of these important enzymes takes place. Regarding the multiple effects of ROS and oxidative stress in cells, we conclude that the down-regulation of these enzymes seem to play a role in the loss of hepatic function observed in the ML cultivation. In addition, enzymes of the urea cycle were clearly down-regulated in ML culture. Proteomics confirms lack in oxidative stress defense mechanisms as the major characteristic of hepatocytes in monolayer cultures compared to sandwich cultures. J. Cell. Biochem. 119: 447-454, 2018. © 2017 Wiley Periodicals, Inc. © 2017 Wiley Periodicals, Inc.

  17. Modulation of protein synthesis and secretion by substratum in primary cultures of rat hepatocytes

    International Nuclear Information System (INIS)

    Sudhakaran, P.R.; Stamatoglou, S.C.; Hughes, R.C.

    1986-01-01

    Hepatocytes isolated by perfusion of adult rat liver and cultured on substrata consisting of one or more of the major components of the liver biomatrix (fibronectin, laminin, type IV collagen) have been examined for the synthesis of defined proteins. Under these conditions, tyrosine amino transferase, a marker of hepatocyte function, is maintained at similar levels in response to dexamethasone over 5 days in culture on each substratum, and total cellular protein synthesis remains constant. By contrast, there is a rapid decrease in synthesis and secretion of albumin and a 3-7-fold increase in synthesis and section of α-fetoprotein which are most marked on a laminin substratum, but least evident on type IV collagen, and an increased synthesis of fibronectin and type IV collagen. The newly synthesized matrix proteins are present in the cell layer as well as in cell secretions. The enhanced synthesis of fibronectin is less in cells seeded onto a fibronectin substratum than on laminin or type IV collagen substrata. These results indicate that hepatocytes cultured in serum-free medium on substrata composed of components of the liver biomatrix maintain certain functions of the differentiated state (tyrosine amino transferase), lose others (albumin secretion) and switch to increased synthesis of matrix components as well as fetal markers such as α-fetoprotein. The magnitude of these effects depends on the substratum on which the hepatocytes are cultured

  18. Fatty acid and amino acid modulation of glucose cycling in isolated rat hepatocytes

    NARCIS (Netherlands)

    Gustafson, LA; Neeft, M; Reijngoud, DJ; Kuipers, F; Sauerwein, HP; Romijn, JA; Herling, AW; Burger, HJ; Meijer, AJ

    2001-01-01

    We studied the influence of glucose/glucose 6-phosphate cycling on glycogen deposition from glucose in fasted-rat hepatocytes using S4048 and CP320626, specific inhibitors of glucose-6-phosphate translocase and glycogen phosphorylase respectively. The effect of amino acids and oleate was also

  19. Recovery of important physiological functions in 3D culture of immortal hepatocytes

    DEFF Research Database (Denmark)

    Wrzesinski, Krzysztof; Fey, S. J.

    2011-01-01

    to grow human liver cells in ‘3 dimensional’ cultures so that they behave very similar to the liver in our bodies. By growing the immortal hepatocytes in specially designed bioreactors they form small pieces of ‘pseudotissue’ which exhibit several of the functions seen in the adult liver. We have grown...

  20. In vitro differentiation and maturation of mouse embryonic stem cells into hepatocytes

    International Nuclear Information System (INIS)

    Ishii, Takamichi; Yasuchika, Kentaro; Fujii, Hideaki; Hoppo, Toshitaka; Baba, Shinji; Naito, Masato; Machimoto, Takafumi; Kamo, Naoko; Suemori, Hirofumi; Nakatsuji, Norio; Ikai, Iwao

    2005-01-01

    It is difficult to induce the maturation of embryonic stem (ES) cells into hepatocytes in vitro. We previously reported that Thy1-positive mesenchymal cells derived from the mouse fetal liver promote the maturation of hepatic progenitor cells. Here, we isolated alpha-fetoprotein (AFP)-producing cells from mouse ES cells for subsequent differentiation into hepatocytes in vitro by coculture with Thy1-positive cells. ES cells expressing green fluorescent protein (GFP) under the control of an AFP promoter were cultured under serum- and feeder layer-free culture conditions. The proportion of GFP-positive cells plateaued at 41.6 ± 12.2% (means ± SD) by day 7. GFP-positive cells, isolated by flow cytometry, were cultured in the presence or absence of Thy1-positive cells as a feeder layer. Isolated GFP-positive cells were stained for AFP, Foxa2, and albumin. The expression of mRNAs encoding tyrosine amino transferase, tryptophan 2,3-dioxygenase, and glucose-6-phosphatase were only detected following coculture with Thy1-positive cells. Following coculture with Thy1-positive cells, the isolated cells produced and stored glycogen. Ammonia clearance activity was also enhanced following coculture. Electron microscopic analysis indicated that the cocultured cells exhibited the morphologic features of mature hepatocytes. In conclusion, coculture with Thy1-positive cells in vitro induced the maturation of AFP-producing cells isolated from ES cell cultures into hepatocytes

  1. MCD-induced steatohepatitis is associated with hepatic adiponectin resistance and adipogenic transformation of hepatocytes.

    Science.gov (United States)

    Larter, Claire Z; Yeh, Matthew M; Williams, Jacqueline; Bell-Anderson, Kim S; Farrell, Geoffrey C

    2008-09-01

    In these studies, we tested the hypothesis that increased lipid intake would exacerbate the severity of nutritional steatohepatitis. C57Bl/6J mice were fed methionine-and-choline deficient (MCD) diets containing 20% (high) or 5% (low) fat by weight for 3 weeks and compared to lipid-matched controls. MCD feeding increased serum ALT levels and induced hepatic steatosis, lobular inflammation and ballooning degeneration of hepatocytes, irrespective of dietary fat content. Hepatic triglyceride accumulation was similar between high and low-fat MCD-fed mice, but lipoperoxide levels were approximately 3-fold higher in the high-fat MCD-fed animals. Serum adiponectin levels increased in MCD-fed mice, although to a lesser extent in high-fat fed animals. AMPK phosphorylation was correspondingly increased in muscle of MCD-fed mice, but hepatic AMPK phosphorylation decreased, and there was little evidence of PPAR alpha activation, suggesting impaired adiponectin action in the livers of MCD-fed animals. Hepatocyte PPAR gamma mRNA levels increased in MCD-fed mice, and were associated with increased aP2 expression, indicating adipogenic transformation of hepatocytes. Increased dietary lipid intake did not alter steatohepatitis severity in MCD-fed mice despite increased lipoperoxide accumulation. Instead, steatohepatitis was associated with impaired hepatic adiponectin action, and adipogenic transformation of hepatocytes in both low and high-fat MCD-fed mice.

  2. [Changes in the chromatin structure of hepatocyte nuclei of rats trained to hypoxia].

    Science.gov (United States)

    Domkina, L K; Bresler, V M; Simanovskiĭ, L N

    1976-03-01

    Structure of chromatin in the nuclei of the isolated surviving hepatocytes and in the isolated nuclei of hepatocytes were studied by fluorochroming with acridine orange and by microfluorimetry of fluorescenc connected with the stain chromatin at 530 and 590 nm in intact rats and in the animals trained to hypoxia in a pressure chamber for 60 days. The nuclei of hepatocytes of intact rats were distributed by fluorescence at 530 nm into three classes with the intensity ratio of 1:2:4; as to the nuclei of hepatocytes of the rats trained to hypoxia - they formed a single class corresponding to the second class of control. In intact rats the ratio of the fluorescence intensity at 590 nm to such at 530 nm (alpha coefficient) formed normal distribution; in trained rats - a bimodal distribution with a shift of the maximum in the direction of reduction and increase of alpha in comparison with control. It is supposed that in hypoxia there is a repression of one and depression of other genes in the chromatine of the nuclei of the liver.

  3. Hyperinsulinemia is associated with increased soluble insulin receptors release from hepatocytes

    Directory of Open Access Journals (Sweden)

    Marcia eHiriart

    2014-06-01

    Full Text Available It has been generally assumed that insulin circulates freely in blood. However it can also interact with plasma proteins. Insulin receptors are located in the membrane of target cells and consist of an alpha and beta subunits with a tyrosine kinase cytoplasmic domain. The ectodomain, called soluble insulin receptor (SIR has been found elevated in patients with diabetes mellitus. We explored if insulin binds to SIRs in circulation under physiological conditions and hypothesize that this SIR may be released by hepatocytes in response to high insulin concentrations. The presence of SIR in rat and human plasmas and the culture medium of hepatocytes was explored using Western blot analysis. A purification protocol was performed to isolated SIR using affinity, gel filtration and ion exchange chromatographies. A modified reverse hemolytic plaque assay was used to measure SIR release from cultured hepatocytes. Incubation with 1 nmol l-1 insulin induces the release of the insulin receptor ectodomains from normal rat hepatocytes. This effect can be partially prevented by blocking protease activity. Furthermore, plasma levels of SIR were higher in a model of metabolic syndrome, where rats are hyperinsulinemic. We also found increased SIR levels in hyperinsulinemic humans. SIR may be an important regulator of the amount of free insulin in circulation. In hyperinsulinemia the amount of this soluble receptor increases, this could lead to higher amounts of insulin bound to this receptor, rather than free insulin, which is the biologically active form of the hormone. This observation could enlighten the mechanisms of insulin resistance.

  4. Hepatocyte caspase-8 is an essential modulator of steatohepatitis in rodents

    NARCIS (Netherlands)

    Hatting, M.; Zhao, G.; Schumacher, F.; Sellge, G.; Masaoudi, Al M.; Gaßler, N.; Boekschoten, M.V.; Müller, M.R.; Liedtke, C.; Cubero, F.J.; Trautwein, C.

    2013-01-01

    In human and murine models of nonalcoholic steatohepatitis (NASH), increased hepatocyte apoptosis is a critical mechanism contributing to inflammation and fibrogenesis. Caspase 8 (Casp8) is essential for death-receptor-mediated apoptosis activity and therefore its modulation might be critical for

  5. Generation of hepatocyte- and endocrine pancreatic-like cells from human induced endodermal progenitor cells

    NARCIS (Netherlands)

    Sambathkumar, Rangarajan; Akkerman, Renate; Dastidar, Sumitava; Roelandt, Philip; Kumar, Manoj; Bajaj, Manmohan; Mestre Rosa, Ana Rita; Helsen, Nicky; Vanslembrouck, Veerle; Kalo, Eric; Khurana, Satish; Laureys, Jos; Gysemans, Conny; Faas, Marijke M; de Vos, Paul; Verfaillie, Catherine M

    2018-01-01

    Multipotent Adult Progenitor Cells (MAPCs) are one potential stem cell source to generate functional hepatocytes or β-cells. However, human MAPCs have less plasticity than pluripotent stem cells (PSCs), as their ability to generate endodermal cells is not robust. Here we studied the role of 14

  6. Ammonia-induced energy disorders interfere with bilirubin metabolism in hepatocytes.

    Science.gov (United States)

    Wang, Qiongye; Wang, Yanfang; Yu, Zujiang; Li, Duolu; Jia, Bin; Li, Jingjing; Guan, Kelei; Zhou, Yubing; Chen, Yanling; Kan, Quancheng

    2014-08-01

    Hyperammonemia and jaundice are the most common clinical symptoms of hepatic failure. Decreasing the level of ammonia in the blood is often accompanied by a reduction in bilirubin in patients with hepatic failure. Previous studies have shown that hyperammonemia can cause bilirubin metabolism disorders, however it is unclear exactly how hyperammonemia interferes with bilirubin metabolism in hepatocytes. The purpose of the current study was to determine the mechanism or mechanisms by which hyperammonemia interferes with bilirubin metabolism in hepatocytes. Cell viability and apoptosis were analyzed in primary hepatocytes that had been exposed to ammonium chloride. Mitochondrial morphology and permeability were observed and analyzed, intermediates of the tricarboxylic acid (TCA) cycle were determined and changes in the expression of enzymes related to bilirubin metabolism were analyzed after ammonia exposure. Hyperammonemia inhibited cell growth, induced apoptosis, damaged the mitochondria and hindered the TCA cycle in hepatocytes. This led to a reduction in energy synthesis, eventually affecting the expression of enzymes related to bilirubin metabolism, which then caused further problems with bilirubin metabolism. These effects were significant, but could be reversed with the addition of adenosine triphosphate (ATP). This study demonstrates that ammonia can cause problems with bilirubin metabolism by interfering with energy synthesis. Copyright © 2014 Elsevier Inc. All rights reserved.

  7. Hepatocyte transplantation improves early survival after partial hepatic resection and irradiation

    International Nuclear Information System (INIS)

    Guha, C.; Sharma, A.; Alfieri, A.; Guha, U.; Sokhi, R.; Gagandeep, S.; Gupta, S.; Vikram, B.; RoyChowdhury, J.

    1997-01-01

    Purpose: Radiation therapy (RT) is limited in its role as an adjuvant therapy of intrahepatic malignancies because of lower tolerance of human liver to irradiation (TD (5(5)) -TD (50(5)) ∼ 30-40 Gy). Although, surgical resection of primary or metastatic hepatic tumors has been shown to prolong survival, it is often limited by the presence of residual disease. RT could potentially improve survival of patients with positive surgical margins. However, radiation damage to the liver may be enhanced by hepatocellular proliferation induced by partial hepatic (PH) resection. We hypothesize that hepatocyte transplantation would be able to provide metabolic support and modulate the development of radiation-induced liver disease post-resection. The present study was designed to test the potential of hepatocyte transplantation in modifying the outcome of hepatocellular damage induced by PH and RT. Methods: Adult male Fischer 344 rats (Charles River) received hepatic irradiation of 50 Gy in a single fraction, after surgical exposure and shielding of the stomach and intestine, using a 320 MGC Philips orthovoltage unit. Immediately following irradiation, a two-third partial hepatectomy was performed. Four days post-radiation, the treatment group was injected with 5 x 10 6 syngeneic hepatocytes into the splenic pulp after a left subcostal incision, which allows homogeneous liver engraftment of the transplanted hepatocytes. Hematoxylin and eosin stains of liver biopsies, performed at various time points (3 days, 1, 2, 3 weeks or, anytime when animals died) were used for histologic evaluation. Time-adjusted survival was calculated from the date of irradiation by the product-limit Kaplan-Meier method, adjusting the denominator at every time point for the number of rats at risk. Results: Eight weeks after RT, 30% (n = 11) of the control animals (PH + 50 Gy) were alive compared to 100% (n = 9) of the transplant recipients (p <0.05). The median survival of the control group was 15

  8. Angiotensin II protects primary rat hepatocytes against bile salt-induced apoptosis.

    Directory of Open Access Journals (Sweden)

    Golnar Karimian

    Full Text Available UNLABELLED: Angiotensin II (AT-II is a pro-fibrotic compound that acts via membrane-bound receptors (AT-1R/AT-2R and thereby activates hepatic stellate cells (HSCs. AT-II receptor blockers (ARBs are thus important candidates in the treatment of liver fibrosis. However, multiple case reports suggest that AT-1R blockers may induce hepatocyte injury. Therefore, we investigated the effect of AT-II and its receptor blockers on cytokine-, oxidative stress- and bile salt-induced cell death in hepatocytes. Primary rat hepatocytes were exposed to TNF-α/Actinomycin D, the ROS-generating agent menadione or the bile salts: glycochenodeoxycholic acid (GCDCA and tauro-lithocholic acid-3 sulfate (TLCS, to induce apoptosis. AT-II (100 nmol/L was added 10 minutes prior to the cell death-inducing agent. AT-1R antagonists (Sartans and the AT-2R antagonist PD123319 were used at 1 µmol/L. Apoptosis (caspase-3 activity, acridine orange staining and necrosis (Sytox green staining were quantified. Expression of CHOP (marker for ER stress and AT-II receptor mRNAs were quantified by Q-PCR. AT-II dose-dependently reduced GCDCA-induced apoptosis of hepatocytes (-50%, p<0.05 without inducing necrosis. In addition, AT-II reduced TLCS-induced apoptosis of hepatocytes (-50%, p<0.05. However, AT-II did not suppress TNF/Act-D and menadione-induced apoptosis. Only the AT-1R antagonists abolished the protective effect of AT-II against GCDCA-induced apoptosis. AT-II increased phosphorylation of ERK and a significant reversal of the protective effect of AT-II was observed when signaling kinases, including ERK, were inhibited. Moreover, AT-II prevented the GCDCA-induced expression of CHOP (the marker of the ER-mediated apoptosis. CONCLUSION: Angiotensin II protects hepatocytes from bile salt-induced apoptosis through a combined activation of PI3-kinase, MAPKs, PKC pathways and inhibition of bile salt-induced ER stress. Our results suggest a mechanism for the observed hepatocyte

  9. Reconfigurable Full-Page Braille Displays

    Science.gov (United States)

    Garner, H. Douglas

    1994-01-01

    Electrically actuated braille display cells of proposed type arrayed together to form full-page braille displays. Like other braille display cells, these provide changeable patterns of bumps driven by digitally recorded text stored on magnetic tapes or in solid-state electronic memories. Proposed cells contain electrorheological fluid. Viscosity of such fluid increases in strong electrostatic field.

  10. Visual Merchandising through Display: Advertising Services Occupations.

    Science.gov (United States)

    Maurer, Nelson S.

    The increasing use of displays by businessmen is creating a demand for display workers. This demand may be met by preparing high school students to enter the field of display. Additional workers might be recruited by offering adult training programs for individuals working within the stores. For this purpose a curriculum guide has been developed…

  11. Software for Minsk-32 display station

    International Nuclear Information System (INIS)

    Belyaeva, L.M.; Gangrskaya, O.G.; Manno, I.; Fefilov, B.V.; Ehsenski, J.

    1976-01-01

    The mathematical provision is described of the Minsk-32 display station. Described is the application of editing program DOSE, assembler translator SLANG and program display-focal. Program DOSE permits to edit the texts with the aid of a rester display on Minsk-32 magnetic tape. The program system permits to use a disk monitor system

  12. U.V.-enhanced reactivation of u.v.-irradiated herpes virus by primary cultures of rat hepatocytes

    International Nuclear Information System (INIS)

    Zurlo, J.; Yager, J.D.

    1984-01-01

    Carcinogen treatment of cultured mammalian cells prior to infection with u.v.-irradiated virus results in enhanced virus survival and mutagenesis suggesting the induction of SOS-type processes. In this paper, we report the development of a primary rat hepatocyte culture system to investigate cellular responses to DNA damage which may be relevant to hepatocarcinogenesis in vivo. We have obtained data demonstrating that enhanced reactivation of u.v.-irradiated Herpes simplex virus type 1 (HSV-1) occurs in hepatocytes irradiated with u.v. Cultured hepatocytes were pretreated with u.v. at the time of enhanced DNA synthesis. These treatments caused an inhibition followed by a recovery of DNA synthesis. At various times after pretreatment, the hepatocytes were infected with control or u.v.-irradiated HSV-1 at low multiplicity, and virus survival was measured by direct plaque assay. U.v.-irradiated HSV-1 exhibited the expected two-component survival curve in control or u.v. pretreated hepatocytes. The magnitude of enhanced reactivation of HSV-1 was dependent on the u.v. dose to the hepatocytes, the time of infection following u.v. pretreatment, and the level of DNA synthesis at the time of pretreatment. These results suggest that u.v. treatment of rat hepatocytes causes the induction of SOS-type functions that may have a role in the initiation of hepatocarcinogenesis

  13. Glycogen content in hepatocytes is related with their size in normal rat liver but not in cirrhotic one.

    Science.gov (United States)

    Bezborodkina, Natalia N; Chestnova, Anna Yu; Vorobev, Mikhail L; Kudryavtsev, Boris N

    2016-04-01

    Hepatocytes differ from one another by the degree of the ploidy, size, position in the liver lobule, and level of the DNA-synthetic processes. It is believed, that the cell size exerts substantial influence on the metabolism of the hepatocytes and the glycogen content in them. The aim of the present study was to test this hypothesis. Dry weight of hepatocytes, their ploidy and glycogen content were determined in the normal and the cirrhotic rat liver. Liver cirrhosis in rats was produced by chronic inhalation of CCl4 vapours in the course of 6 months. A combined cytophotometric method was used. Dry weight of the cell, its glycogen and DNA content were successively measured on a mapped preparation. Hepatocytes of each ploidy class in the normal and the cirrhotic rat liver accumulated glycogen at the same rate. In the normal liver, there was a distinct correlation between the size of hepatocytes and glycogen content in them. This correlation was observed in each ploidy class, and was especially pronounced in the class of mononucleate tetraploid hepatocytes. In the cirrhotic liver, there was no correlation between the size of the cells and their glycogen content. The impairment of liver lobular structure probably explains the observed lack of correlation between hepatocyte size and their glycogen content in the cirrhotic liver. © 2016 International Society for Advancement of Cytometry. © 2016 International Society for Advancement of Cytometry.

  14. Impaired mitochondrial functions contribute to 3-bromopyruvate toxicity in primary rat and mouse hepatocytes.

    Science.gov (United States)

    Sobotka, Ondřej; Endlicher, René; Drahota, Zdeněk; Kučera, Otto; Rychtrmoc, David; Raad, Marjan; Hakeem, Khurum; Červinková, Zuzana

    2016-08-01

    A compound with promising anticancer properties, 3-bromopyruvate (3-BP) is a synthetic derivative of a pyruvate molecule; however, its toxicity in non-malignant cells has not yet been fully elucidated. Therefore, we elected to study the effects of 3-BP on primary hepatocytes in monolayer cultures, permeabilized hepatocytes and isolated mitochondria. After a 1-h treatment with 100 μM 3-BP cell viability of rat hepatocytes was decreased by 30 % as measured by the WST-1 test (p < 0.001); after 3-h exposure to ≥200 μM 3-BP lactate dehydrogenase leakage was increased (p < 0.001). Reactive oxygen species production was increased in the cell cultures after a 1-h treatment at concentrations ≥100 μmol/l (p < 0.01), and caspase 3 activity was increased after a 20-h incubation with 150 μM and 200 μM 3-BP (p < 0.001). This toxic effect of 3-BP was also proved using primary mouse hepatocytes. In isolated mitochondria, 3-BP induced a dose- and time-dependent decrease of mitochondrial membrane potential during a 10-min incubation both with Complex I substrates glutamate + malate or Complex II substrate succinate, although this decrease was more pronounced with the latter. We also measured the effect of 3-BP on respiration of isolated mitochondria. ADP-activated respiration was inhibited by 20 μM 3-BP within 10 min. Similar effects were also found in permeabilized hepatocytes of both species.

  15. Insulin-like growth factor-II receptors in cultured rat hepatocytes: regulation by cell density

    International Nuclear Information System (INIS)

    Scott, C.D.; Baxter, R.C.

    1987-01-01

    Insulin-like growth factor-II (IGF-II) receptors in primary cultures of adult rat hepatocytes were characterized and their regulation by cell density examined. In hepatocytes cultured at 5 X 10(5) cells per 3.8 cm2 plate [ 125 I]IGF-II bound to specific, high affinity receptors (Ka = 4.4 +/- 0.5 X 10(9) l/mol). Less than 1% cross-reactivity by IGF-I and no cross-reactivity by insulin were observed. IGF-II binding increased when cells were permeabilized with 0.01% digitonin, suggesting the presence of an intracellular receptor pool. Determined by Scatchard analysis and by polyacrylamide gel electrophoresis after affinity labeling, the higher binding was due solely to an increase in binding sites present on 220 kDa type II IGF receptors. In hepatocytes cultured at low densities, the number of cell surface receptors increased markedly, from 10-20,000 receptors per cell at a culture density of 6 X 10(5) cells/well to 70-80,000 receptors per cell at 0.38 X 10(5) cells/well. The increase was not due simply to the exposure of receptors from the intracellular pool, as a density-related increase in receptors was also seen in cells permeabilized with digitonin. There was no evidence that IGF binding proteins, either secreted by hepatocytes or present in fetal calf serum, had any effect on the measurement of receptor concentration or affinity. We conclude that rat hepatocytes in primary culture contain specific IGF-II receptors and that both cell surface and intracellular receptors are regulated by cell density

  16. Hepatocyte-based in vitro model for assessment of drug-induced cholestasis

    International Nuclear Information System (INIS)

    Chatterjee, Sagnik; Richert, Lysiane; Augustijns, Patrick; Annaert, Pieter

    2014-01-01

    Early detection of drug-induced cholestasis remains a challenge during drug development. We have developed and validated a biorelevant sandwich-cultured hepatocytes- (SCH) based model that can identify compounds causing cholestasis by altering bile acid disposition. Human and rat SCH were exposed (24–48 h) to known cholestatic and/or hepatotoxic compounds, in the presence or in the absence of a concentrated mixture of bile acids (BAs). Urea assay was used to assess (compromised) hepatocyte functionality at the end of the incubations. The cholestatic potential of the compounds was expressed by calculating a drug-induced cholestasis index (DICI), reflecting the relative residual urea formation by hepatocytes co-incubated with BAs and test compound as compared to hepatocytes treated with test compound alone. Compounds with clinical reports of cholestasis, including cyclosporin A, troglitazone, chlorpromazine, bosentan, ticlopidine, ritonavir, and midecamycin showed enhanced toxicity in the presence of BAs (DICI ≤ 0.8) for at least one of the tested concentrations. In contrast, the in vitro toxicity of compounds causing hepatotoxicity by other mechanisms (including diclofenac, valproic acid, amiodarone and acetaminophen), remained unchanged in the presence of BAs. A safety margin (SM) for drug-induced cholestasis was calculated as the ratio of lowest in vitro concentration for which was DICI ≤ 0.8, to the reported mean peak therapeutic plasma concentration. SM values obtained in human SCH correlated well with reported % incidence of clinical drug-induced cholestasis, while no correlation was observed in rat SCH. This in vitro model enables early identification of drug candidates causing cholestasis by disturbed BA handling. - Highlights: • Novel in vitro assay to detect drug-induced cholestasis • Rat and human sandwich-cultured hepatocytes (SCH) as in vitro models • Cholestatic compounds sensitize SCH to toxic effects of accumulating bile acids • Drug

  17. Intracellular pH regulation in hepatocytes isolated from three teleost species.

    Science.gov (United States)

    Furimsky, M; Moon, T W; Perry, S F

    1999-09-01

    The mechanisms of intracellular pH (pH(i)) regulation were studied in hepatocytes isolated from three species of teleost: rainbow trout (Oncorhynchus mykiss), black bullhead (Ameiurus melas) and American eel (Anguilla rostrata). Intracellular pH was monitored over time using the pH-sensitive fluorescent dye BCECF in response to acid loading under control conditions and in different experimental media containing either low Na(+) or Cl(-) concentrations, the Na(+)-H(+) exchanger blocker amiloride or the blocker of the V-type H(+)-ATPase, bafilomycin A(1). In trout and bullhead hepatocytes, recovery to an intracellular acid load occurred principally by way of a Na(+)-dependent amiloride-sensitive Na(+)-H(+) exchanger. In eel hepatocytes, the Na(+)-H(+) exchanger did not contribute to recovery to an acid load though evidence suggests that it is present on the cell membrane and participates in the maintenance of steady-state pH(i). The V-type H(+)-ATPase did not participate in recovery to an acid load in any species. A Cl(-)-HCO(3)(-) exchanger may play a role in recovery to an acid load in eel hepatocytes by switching off and retaining base that would normally be tonically extruded. Thus, it is clear that hepatocytes isolated from the three species are capable of regulating pH(i), principally by way of a Na(+)-H(+) exchanger and a Cl(-)-HCO(3)(-) exchanger, but do not exploit identical mechanisms for pH(i) recovery. J. Exp. Zool. 284:361-367, 1999. Copyright 1999 Wiley-Liss, Inc.

  18. Stathmin Mediates Hepatocyte Resistance to Death from Oxidative Stress by down Regulating JNK

    Science.gov (United States)

    Zhao, Enpeng; Amir, Muhammad; Lin, Yu; Czaja, Mark J.

    2014-01-01

    Stathmin 1 performs a critical function in cell proliferation by regulating microtubule polymerization. This proliferative function is thought to explain the frequent overexpression of stathmin in human cancer and its correlation with a bad prognosis. Whether stathmin also functions in cell death pathways is unclear. Stathmin regulates microtubules in part by binding free tubulin, a process inhibited by stathmin phosphorylation from kinases including c-Jun N-terminal kinase (JNK). The involvement of JNK activation both in stathmin phosphorylation, and in hepatocellular resistance to oxidative stress, led to an examination of the role of stathmin/JNK crosstalk in oxidant-induced hepatocyte death. Oxidative stress from menadione-generated superoxide induced JNK-dependent stathmin phosphorylation at Ser-16, Ser-25 and Ser-38 in hepatocytes. A stathmin knockdown sensitized hepatocytes to both apoptotic and necrotic cell death from menadione without altering levels of oxidant generation. The absence of stathmin during oxidative stress led to JNK overactivation that was the mechanism of cell death as a concomitant knockdown of JNK1 or JNK2 blocked death. Hepatocyte death from JNK overactivation was mediated by the effects of JNK on mitochondria. Mitochondrial outer membrane permeabilization occurred in stathmin knockdown cells at low concentrations of menadione that triggered apoptosis, whereas mitochondrial β-oxidation and ATP homeostasis were compromised at higher, necrotic menadione concentrations. Stathmin therefore mediates hepatocyte resistance to death from oxidative stress by down regulating JNK and maintaining mitochondrial integrity. These findings demonstrate a new mechanism by which stathmin promotes cell survival and potentially tumor growth. PMID:25285524

  19. Stathmin mediates hepatocyte resistance to death from oxidative stress by down regulating JNK.

    Directory of Open Access Journals (Sweden)

    Enpeng Zhao

    Full Text Available Stathmin 1 performs a critical function in cell proliferation by regulating microtubule polymerization. This proliferative function is thought to explain the frequent overexpression of stathmin in human cancer and its correlation with a bad prognosis. Whether stathmin also functions in cell death pathways is unclear. Stathmin regulates microtubules in part by binding free tubulin, a process inhibited by stathmin phosphorylation from kinases including c-Jun N-terminal kinase (JNK. The involvement of JNK activation both in stathmin phosphorylation, and in hepatocellular resistance to oxidative stress, led to an examination of the role of stathmin/JNK crosstalk in oxidant-induced hepatocyte death. Oxidative stress from menadione-generated superoxide induced JNK-dependent stathmin phosphorylation at Ser-16, Ser-25 and Ser-38 in hepatocytes. A stathmin knockdown sensitized hepatocytes to both apoptotic and necrotic cell death from menadione without altering levels of oxidant generation. The absence of stathmin during oxidative stress led to JNK overactivation that was the mechanism of cell death as a concomitant knockdown of JNK1 or JNK2 blocked death. Hepatocyte death from JNK overactivation was mediated by the effects of JNK on mitochondria. Mitochondrial outer membrane permeabilization occurred in stathmin knockdown cells at low concentrations of menadione that triggered apoptosis, whereas mitochondrial β-oxidation and ATP homeostasis were compromised at higher, necrotic menadione concentrations. Stathmin therefore mediates hepatocyte resistance to death from oxidative stress by down regulating JNK and maintaining mitochondrial integrity. These findings demonstrate a new mechanism by which stathmin promotes cell survival and potentially tumor growth.

  20. Tributyltin induces apoptotic signaling in hepatocytes through pathways involving the endoplasmic reticulum and mitochondria

    International Nuclear Information System (INIS)

    Grondin, Melanie; Marion, Michel; Denizeau, Francine; Averill-Bates, Diana A.

    2007-01-01

    Tri-n-butyltin is a widespread environmental toxicant, which accumulates in the liver. This study investigates whether tri-n-butyltin induces pro-apoptotic signaling in rat liver hepatocytes through pathways involving the endoplasmic reticulum and mitochondria. Tri-n-butyltin activated the endoplasmic reticulum pathway of apoptosis, which was demonstrated by the activation of the protease calpain, its translocation to the plasma membrane, followed by cleavage of the calpain substrates, cytoskeletal protein vinculin, and caspase-12. Caspase-12 is localized to the cytoplasmic side of the endoplasmic reticulum and is involved in apoptosis mediated by the endoplasmic reticulum. Tri-n-butyltin also caused translocation of the pro-apoptotic proteins Bax and Bad from the cytosol to mitochondria, as well as changes in mitochondrial membrane permeability, events which can activate the mitochondrial death pathway. Tri-n-butyltin induced downstream apoptotic events in rat hepatocytes at the nuclear level, detected by chromatin condensation and by confocal microscopy using acridine orange. We investigated whether the tri-n-butyltin-induced pro-apoptotic events in hepatocytes could be linked to perturbation of intracellular calcium homeostasis, using confocal microscopy. Tri-n-butyltin caused changes in intracellular calcium distribution, which were similar to those induced by thapsigargin. Calcium was released from a subcellular compartment, which is likely to be the endoplasmic reticulum, into the cytosol. Cytosolic acidification, which is known to trigger apoptosis, also occurred and involved the Cl - /HCO 3 - exchanger. Pro-apoptotic events in hepatocytes were inhibited by the calcium chelator, Bapta-AM, and by a calpain inhibitor, which suggests that changes in intracellular calcium homeostasis are involved in tri-n-butyltin-induced apoptotic signaling in rat hepatocytes

  1. Optimization of the isolation and cultivation of Cyprinus carpio primary hepatocytes

    Science.gov (United States)

    Yanhong, Fan; Chenghua, He; Guofang, Liu

    2008-01-01

    The aquatic environment is affected by numerous chemical contaminants. There is an increasing need to identify these chemicals and to evaluate their potential toxicity towards aquatic life. In this research we optimized techniques for primary cell culture of Cyprinus carpio hepatocytes as one adjunct model for ecotoxicological evaluation of the potential hazards of xenobiotics in the aquatic environment. In this study, Cyprinus carpio hepatocytes were isolated by mechanical separation, two-step collagenase perfusion, and pancreatin digestion. The hepatocytes or parenchymal cells could be separated from cell debris and from non-parenchymal cells by low-speed centrifugation (Percoll gradient centrifugation). The harvested hepatocytes were suspended in DMEM, M199 (cultured in 5% CO2), or L-15 (cultured without 5% CO2) medium then cultured at 17, 27, or 37 °C. Cell yield was counted by use of a hemocytometer, and the viability of the cells was assessed by use of the Trypan blue exclusion test. Results from these studies showed that the best method of isolation was pancreatin digestion (the cell yield was 2.7 × 108 per g (liver weight) and the viability was 98.4%) and the best medium was M199 (cultured in 5% CO2) or L-15 (cultured without 5% CO2). The optimum culture temperature was 27 °C. The primary hepatocytes culture of Cyprimus carpio grew well and satisfied requirements for most toxicological experiments in this condition. PMID:19002769

  2. Glucose production and storage in hepatocytes isolated from normal versus diabetic rats

    International Nuclear Information System (INIS)

    Olivieri, M.C.; Dragland-Meserve, C.J.; Parker Botelho, L.H.

    1987-01-01

    The rates of glucose production and storage were compared in hepatocytes isolated from normal versus insulin-resistant diabetic rats. A single low-dose (40 mg/kg) IV injection of streptozotocin to 250 g rats resulted in a Type II diabetic animal model which was hyperglycemic with normal insulin levels. Addition of 8 mM 14 C-lactate and 2 mM pyruvate to hepatocytes resulted in a linear increase in total glucose production ( 14 C-glucose and unlabeled glucose) and incorporation into glycogen measured over 120 min. The rate of gluconeogenesis was estimated from the production of 14 C-glucose and the rate of glycogenolysis was estimated from the production of unlabeled glucose in cells incubated in the presence or absence of 14 C-labelled substrate. There was not significant difference in total glucose production in hepatocytes isolated from normal versus diabetic rats, however, the contribution from gluconeogenesis versus glycogenolysis was significantly different. Following a 1 h incubation of cells from normal rats, 42% of the total glucose production was due to gluconeogenesis and 58% was due to glycogenolysis. In cells from diabetic rats, 83% of total glucose production was from gluconeogenesis and 17% from glycogenolysis. Also, incubation with 14 C-lactate/pyruvate resulted in a 3.3-fold increase in 14 C-glucose incorporation into glycogen in hepatocytes isolated from normal rats compared to diabetic rats. These data suggest that alterations occur in the rate-limiting enzymes responsible for glucose production and storage in hepatocytes isolated from a rat model of insulin-resistant Type II diabetes

  3. Hepatocyte-based in vitro model for assessment of drug-induced cholestasis

    Energy Technology Data Exchange (ETDEWEB)

    Chatterjee, Sagnik, E-mail: Sagnik.Chatterjee@pharm.kuleuven.be [Drug Delivery and Disposition, KU Leuven Department of Pharmaceutical and Pharmacological Sciences, O and N2, Herestraat 49 — bus 921, 3000 Leuven (Belgium); Richert, Lysiane, E-mail: l.richert@kaly-cell.com [KaLy-Cell, 20A rue du Général Leclerc, 67115 Plobsheim (France); Augustijns, Patrick, E-mail: Patrick.Augustijns@pharm.kuleuven.be [Drug Delivery and Disposition, KU Leuven Department of Pharmaceutical and Pharmacological Sciences, O and N2, Herestraat 49 — bus 921, 3000 Leuven (Belgium); Annaert, Pieter, E-mail: Pieter.Annaert@pharm.kuleuven.be [Drug Delivery and Disposition, KU Leuven Department of Pharmaceutical and Pharmacological Sciences, O and N2, Herestraat 49 — bus 921, 3000 Leuven (Belgium)

    2014-01-01

    Early detection of drug-induced cholestasis remains a challenge during drug development. We have developed and validated a biorelevant sandwich-cultured hepatocytes- (SCH) based model that can identify compounds causing cholestasis by altering bile acid disposition. Human and rat SCH were exposed (24–48 h) to known cholestatic and/or hepatotoxic compounds, in the presence or in the absence of a concentrated mixture of bile acids (BAs). Urea assay was used to assess (compromised) hepatocyte functionality at the end of the incubations. The cholestatic potential of the compounds was expressed by calculating a drug-induced cholestasis index (DICI), reflecting the relative residual urea formation by hepatocytes co-incubated with BAs and test compound as compared to hepatocytes treated with test compound alone. Compounds with clinical reports of cholestasis, including cyclosporin A, troglitazone, chlorpromazine, bosentan, ticlopidine, ritonavir, and midecamycin showed enhanced toxicity in the presence of BAs (DICI ≤ 0.8) for at least one of the tested concentrations. In contrast, the in vitro toxicity of compounds causing hepatotoxicity by other mechanisms (including diclofenac, valproic acid, amiodarone and acetaminophen), remained unchanged in the presence of BAs. A safety margin (SM) for drug-induced cholestasis was calculated as the ratio of lowest in vitro concentration for which was DICI ≤ 0.8, to the reported mean peak therapeutic plasma concentration. SM values obtained in human SCH correlated well with reported % incidence of clinical drug-induced cholestasis, while no correlation was observed in rat SCH. This in vitro model enables early identification of drug candidates causing cholestasis by disturbed BA handling. - Highlights: • Novel in vitro assay to detect drug-induced cholestasis • Rat and human sandwich-cultured hepatocytes (SCH) as in vitro models • Cholestatic compounds sensitize SCH to toxic effects of accumulating bile acids • Drug

  4. Modulation of Mitochondrial DNA Copy Number to Induce Hepatocytic Differentiation of Human Amniotic Epithelial Cells.

    Science.gov (United States)

    Vaghjiani, Vijesh; Cain, Jason E; Lee, William; Vaithilingam, Vijayaganapathy; Tuch, Bernard E; St John, Justin C

    2017-10-15

    Mitochondrial deoxyribonucleic acid (mtDNA) copy number is tightly regulated during pluripotency and differentiation. There is increased demand of cellular adenosine triphosphate (ATP) during differentiation for energy-intensive cell types such as hepatocytes and neurons to meet the cell's functional requirements. During hepatocyte differentiation, mtDNA copy number should be synchronously increased to generate sufficient ATP through oxidative phosphorylation. Unlike bone marrow mesenchymal cells, mtDNA copy number failed to increase by 28 days of differentiation of human amniotic epithelial cells (hAEC) into hepatocyte-like cells (HLC) despite their expression of some end-stage hepatic markers. This was due to higher levels of DNA methylation at exon 2 of POLGA, the mtDNA-specific replication factor. Treatment with a DNA demethylation agent, 5-azacytidine, resulted in increased mtDNA copy number, reduced DNA methylation at exon 2 of POLGA, and reduced hepatic gene expression. Depletion of mtDNA followed by subsequent differentiation did not increase mtDNA copy number, but reduced DNA methylation at exon 2 of POLGA and increased expression of hepatic and pluripotency genes. We encapsulated hAEC in barium alginate microcapsules and subsequently differentiated them into HLC. Encapsulation resulted in no net increase of mtDNA copy number but a significant reduction in DNA methylation of POLGA. RNAseq analysis showed that differentiated HLC express hepatocyte-specific genes but also increased expression of inflammatory interferon genes. Differentiation in encapsulated cells showed suppression of inflammatory genes as well as increased expression of genes associated with hepatocyte function pathways and networks. This study demonstrates that an increase in classical hepatic gene expression can be achieved in HLC through encapsulation, although they fail to effectively regulate mtDNA copy number.

  5. Differentiation of human umbilical cord mesenchymal stromal cells into low immunogenic hepatocyte-like cells.

    Science.gov (United States)

    Zhao, Qinjun; Ren, Hongying; Li, Xiyuan; Chen, Zhong; Zhang, Xiangyu; Gong, Wei; Liu, Yongjun; Pang, Tianxiang; Han, Zhong Chao

    2009-01-01

    Mesenchymal stromal cells (MSC) isolated from several human tissues have been known to differentiate into the hepatic lineage in vitro, but the immunogenicity of the differentiated hepatocyte-like cells (DHC) has not been reported. Umbilical cord (UC) MSC are thought to be an attractive cell source for cell therapy because of their young age and low infection rate compared with adult tissue MSC. Hepatic differentiation of UC-MSC was induced with a 2-step protocol. The expressions of hepatic markers were detected by RT-PCR and immunofluorescence staining. Albumin production and urea secretion were measured by ELISA and colorimetric assay respectively. The immunosuppressive properties of DHC was detected by mixed lymphocyte culture. After incubation with specific growth factors, including hepatocyte growth factor (HGF) and basic fibroblast growth factor (bFGF), UC MSC exhibited a high hepatic differentiation ability in an adherent culture condition. The differentiated UC MSC showed hepatocyte-like morphology and expressed several liver-specific markers at gene and protein levels. Furthermore, the DHC exhibited hepatocyte-specific functions, including albumin secretion, low-density lipoprotein uptake and urea production. More importantly, DHC did not express major histocompatibility complex (MHC) II antigen and were not able to induce lymphocyte proliferation in mixed lymphocyte culture, as undifferentiated UC MSC did. Our results indicate that UC MSC are able to differentiate into functional hepatocyte-like cells that still retain their low immunogenicity in vitro. More importantly, DHC incorporated into the parenchyma of liver when transplanted into mice with CCl(4)-induced liver injury. Therefore, DHC may be an ideal source for cell therapy of liver diseases.

  6. Independent, parallel pathways to CXCL10 induction in HCV-infected hepatocytes.

    Science.gov (United States)

    Brownell, Jessica; Wagoner, Jessica; Lovelace, Erica S; Thirstrup, Derek; Mohar, Isaac; Smith, Wesley; Giugliano, Silvia; Li, Kui; Crispe, I Nicholas; Rosen, Hugo R; Polyak, Stephen J

    2013-10-01

    The pro-inflammatory chemokine CXCL10 is induced by HCV infection in vitro and in vivo, and is associated with outcome of IFN (interferon)-based therapy. We studied how hepatocyte sensing of early HCV infection via TLR3 (Toll-like receptor 3) and RIG-I (retinoic acid inducible gene I) led to expression of CXCL10. CXCL10, type I IFN, and type III IFN mRNAs and proteins were measured in PHH (primary human hepatocytes) and hepatocyte lines harboring functional or non-functional TLR3 and RIG-I pathways following HCV infection or exposure to receptor-specific stimuli. HuH7 human hepatoma cells expressing both TLR3 and RIG-I produced maximal CXCL10 during early HCV infection. Neutralization of type I and type III IFNs had no impact on virus-induced CXCL10 expression in TLR3+/RIG-I+ HuH7 cells, but reduced CXCL10 expression in PHH. PHH cultures were positive for monocyte, macrophage, and dendritic cell mRNAs. Immunodepletion of non-parenchymal cells (NPCs) eliminated marker expression in PHH cultures, which then showed no IFN requirement for CXCL10 induction during HCV infection. Immunofluorescence studies also revealed a positive correlation between intracellular HCV Core and CXCL10 protein expression (r(2) = 0.88, p ≤ 0.001). While CXCL10 induction in hepatocytes during the initial phase of HCV infection is independent of hepatocyte-derived type I and type III IFNs, NPC-derived IFNs contribute to CXCL10 induction during HCV infection in PHH cultures. Copyright © 2013 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  7. Metabolism of cysteine by cyteinesulfinate-independent pathway(s) in rat hepatocytes

    International Nuclear Information System (INIS)

    Stipanuk, M.H.; De La Rosa, J.; Drake, M.R.

    1986-01-01

    The metabolism of cysteine (CYS) and that of cysteinesulfinate (CSA) were studied in freshly isolated hepatocytes from fed rats. In incubations of rat hepatocytes with either 1 or 25 mM CSA, over 90% of the 14 CO 2 formed from [1- 14 C]CSA could be accounted for by production of hypotaurine plus taurine. In similar incubations with 1 or 25 mM CYS, only 4% of 14 CO 2 evolution from [1- 14 C]CYS could be accounted for by production of hypotaurine plus taurine. Addition of unlabeled CSA inhibited recovery of label from [1- 14 C]CYS as 14 CO 2 by 33%. Metabolism of CYS and of CSA were affected differently by addition of α-ketoglutarate, a cosubstrate for transamination, or of propargylglycine, an inhibitor of cystathionase activity. These data suggest that a substantial proportion of CYS is catabolized by CSA-independent pathways in the rat hepatocyte. Although addition of α-ketoglutarate to incubations of hepatocytes with CSA resulted in a marked increase in CSA catabolism via the transamination pathway, addition of keto acids to incubation systems had little or no effect on production of any metabolite from CYS. Thus, CYS transamination does not appear to be a major pathway of CYS metabolism in the hepatocyte. Inhibition of cystathionase with propargylglycine reduced both 14 CO 2 production from [1- 14 C]CYS and ammonia plus urea nitrogen production from CYS by about 50%; CSA catabolism was not affected. Thus, cleavage of cyst(e)ine by cystathionase may be an important physiological pathway for CYS catabolism in the liver

  8. Hepatitis E Virus Induces Hepatocyte Apoptosis via Mitochondrial Pathway in Mongolian Gerbils

    Directory of Open Access Journals (Sweden)

    Yifei Yang

    2018-03-01

    Full Text Available Previous studies demonstrated that Mongolian gerbils can be infected by hepatitis E virus (HEV, which induces the hepatic injury. Here, the mitochondria in hepatocytes from HEV-infected gerbils were considerably swollen, thin cristae. After HEV infection, the activity of superoxide dismutase significantly decreased (p < 0.01, while malondialdehyde concentrations significantly increased, compared with those in the control group (p < 0.01. Adenosine triphosphatase levels decreased significantly in the hepatocyte of the inoculated groups, compared with those in control group (p < 0.05 at days 21, 28, 42 post-inoculation (dpi as well. Furthermore, the levels of ATP synthetase ATP5A1 significantly decreased during HEV infection, compared with those in the control group (p < 0.05. According to the TdT mediated dUTP nick end labeling (TUNEL detection, TUNEL positive hepatocytes increased in the inoculated group, compared with that in the control group (p < 0.05. Up-regulation of the mitochondrion-mediated apoptosis regulating proteins, Bax and Bcl-2, in the HEV-infected gerbils (p < 0.05 was observed. However, cytochrome c levels in mitochondria decreased, while this molecule was detected in the cytoplasm of the infected animals, in contrast to that in the control group. Apaf-1, and active caspase-9 and -3 levels were shown to be significantly higher in the inoculated group compared with those in the control group (p < 0.05. Taken together, our results demonstrated that HEV infection induces hepatocyte injuries and activity of the mitochondrial apoptotic pathway, which trigger the hepatocyte apoptosis in Mongolian gerbils.

  9. Acrolein cytotoxicity in hepatocytes involves endoplasmic reticulum stress, mitochondrial dysfunction and oxidative stress

    Science.gov (United States)

    Mohammad, Mohammad K; Avila, Diana; Zhang, Jingwen; Barve, Shirish; Arteel, Gavin; McClain, Craig; Joshi-Barve, Swati

    2012-01-01

    Acrolein is a common environmental, food and water pollutant and a major component of cigarette smoke. Also, it is produced endogenously via lipid peroxidation and cellular metabolism of certain amino acids and drugs. Acrolein is cytotoxic to many cell types including hepatocytes; however the mechanisms are not fully understood. We examined the molecular mechanisms underlying acrolein hepatotoxicity in primary human hepatocytes and hepatoma cells. Acrolein, at pathophysiological concentrations, caused a dose-dependent loss of viability of hepatocytes. The death was apoptotic at moderate and necrotic at high concentrations of acrolein. Acrolein exposure rapidly and dramatically decreased intracellular glutathione and overall antioxidant capacity, and activated the stress-signaling MAP-kinases JNK, p42/44 and p38. Our data demonstrate for the first time in human hepatocytes, that acrolein triggered endoplasmic reticulum (ER) stress and activated eIF2α, ATF-3 and -4, and Gadd153/CHOP, resulting in cell death. Notably, the protective/adaptive component of ER stress was not activated, and acrolein failed to up-regulate the protective ER-chaperones, GRP78 and GRP94. Additionally, exposure to acrolein disrupted mitochondrial integrity/function, and led to the release of pro-apoptotic proteins and ATP depletion. Acrolein-induced cell death was attenuated by N-acetyl cysteine, phenyl-butyric acid, and caspase and JNK inhibitors. Our data demonstrate that exposure to acrolein induces a variety of stress responses in hepatocytes, including GSH depletion, oxidative stress, mitochondrial dysfunction and ER stress (without ER-protective responses) which together contribute to acrolein toxicity. Our study defines basic mechanisms underlying liver injury caused by reactive aldehyde pollutants such as acrolein. PMID:23026831

  10. Metabolism of methyl-branched iodo palmitic acids in cultured hepatocytes

    International Nuclear Information System (INIS)

    Thomas, G.; Pepin, D.; Loriette, C.; Chambaz, J.; Bereziat, G.; Vidal, M.; Apparu, M.; Coornaert, S.

    1989-01-01

    The metabolic fate of methyl-branched iodo fatty acids was studied in primary culture of rat hepatocytes. We compared 16-iodo-2-R,S-methyl palmitic acid (2-Me), which can be β oxidized, with 16-iodo-3-R,S-methyl palmitic acid (3-Me) which can be β oxidized only after an initial α oxydation and with 16-iodo-2,2-dimethyl palmitic acid (2,2-Me 2 ) and 16-iodo-3,3-dimethyl palmitic acid (3,3-Me 2 ) which cannot be β oxidized at all. The normal fate of natural fatty acids was given by comparative experiments with [1- 14 C] palmitic acid. Monomethyl-branched iodo fatty acids were taken up in the same range as palmitic acid but more than dimethyl-branched iodo fatty acids. After a 15-h incubation, acido-soluble products (ASP) accounted for 75% of the radioactivity taken up as 16-iodo-2-methyl palmitic acid, 50% as other methyl-branched iodo fatty acids and only 30% as palmitic acid. Cultured hepatocytes, labelled for 3 h with the various fatty acids and reincubated for 12 h without fatty acid, secreted large amounts of free dimethyl-branched iodo fatty acids as compared to the monomethyl ones and palmitic acid. Only hepatocytes prelabelled with 16-[ 125 I]iodo-2,2-dimethyl palmitic acid exhibited an appreciable secretion of labeled triglycerides, but at a lower rate than with [1- 14 C] palmitic acid. Conversely, the 16-iodo-monomethyl palmitic acids remained chiefly in hepatocyte triglycerides. Minute amounts of 16-iodo-methyl-branched palmitic acids were found in hepatocyte or secreted phospholipids as compared with palmitic acid. (orig.)

  11. Cadmium-induced apoptosis through the mitochondrial pathway in rainbow trout hepatocytes: involvement of oxidative stress

    International Nuclear Information System (INIS)

    Risso-de Faverney, C.; Orsini, N.; Sousa, G. de; Rahmani, R.

    2004-01-01

    Cadmium (Cd) induces oxidative stress and apoptosis in trout hepatocytes. We therefore investigated the involvement of the mitochondrial pathway in the initiation of apoptosis and the possible role of oxidative stress in that process. This study demonstrates that hepatocyte exposure to Cd (2, 5 and 10 μM) triggers significant caspase-3, but also caspase-8 and -9 activation in a dose-dependent manner. Western-blot analysis of hepatocyte mitochondrial and cytosolic fractions revealed that cytochrome c (Cyt c) was released in the cytosol in a dose-dependent manner, whereas the pro-apoptotic protein Bax was redistributed to mitochondria after 24 and 48 h exposure. We also found that the expression of anti-apoptotic protein Bcl-xL, known to be regulated under mild oxidative stress to protect cells from apoptosis, did not change after 3 and 6 h exposure to Cd, then increased after 24 and 48 h exposure to 10 μM Cd. In the second part of this work, two antioxidant agents, 2,2,6,6-tetramethylpiperidinyl-1-oxyl (TEMPO) (100 μM) and N-acetylcysteine (NAC, 100 μM) were used to determine the involvement of reactive oxygen species (ROS) in Cd-induced apoptosis. Simultaneously exposing trout hepatocytes to Cd and TEMPO or NAC significantly reduced caspase-3 activation after 48 h and had a suppressive effect on caspase-8 and -9 also, mostly after 24 h. Lastly, the presence of either one of these antioxidants in the treatment medium also attenuated Cd-induced Cyt c release in cytosol and the level of Bax in the mitochondria after 24 and 48 h, while high Bcl-xL expression was observed. Taken together, these data clearly evidenced the key role of mitochondria in the cascade of events leading to trout hepatocyte apoptosis in response to Cd and the relationship that exists between oxidative stress and cell death

  12. Hepatocyte membrane injury and bleb formation following low dose comfrey toxicity in rats.

    Science.gov (United States)

    Yeong, M L; Wakefield, S J; Ford, H C

    1993-04-01

    Comfrey, a popular herbal remedy, contains hepatotoxic pyrrolizidine alkaloids and has been implicated in recent human toxicity. Although alkaloids from other plant sources have been extensively researched, studies on the hepatotoxic effects of comfrey alkaloids are scant. The effects of high dose comfrey toxicity have been studied and the present investigation was undertaken to identify changes associated with relatively low dose toxicity. Eight young adult rats were dosed weekly for six weeks with 50 mg/kg of comfrey derived alkaloids. The animals were dissected one week after the last dose and the livers examined by light and electron microscopy. Changes at the light microscopic level showed vascular congestion, mild zone 3 necrosis and loss of definition of hepatocyte cellular membranes. Extensive ultrastructural abnormalities were identified in the form of endothelial sloughing and the loss of hepatocyte microvilli. A striking finding was florid bleb formation on the sinusoidal borders of hepatocytes. Many blebs were shed into the space of Disse and extruded to fill, and sometimes occlude, sinusoidal lumina. Platelets were frequently found in areas of bleb formation. There was evidence of late damage in collagenization of Disse's space. Hepatocyte bleb formation is known to occur under a variety of pathological conditions but there is little to no information in the literature on the effects, if any, of bleb formation on fibrogenesis and the microcirculation and its role in the pathogenesis of liver disease. The pyrrolizidine alkaloids of comfrey may serve as an experimental tool to study the process of bleb formation and the intimate relationship between hepatocyte and sinusoidal injury in the liver.

  13. Designing a better weather display

    Science.gov (United States)

    Ware, Colin; Plumlee, Matthew

    2012-01-01

    The variables most commonly displayed on weather maps are atmospheric pressure, wind speed and direction, and surface temperature. But they are usually shown separately, not together on a single map. As a design exercise, we set the goal of finding out if it is possible to show all three variables (two 2D scalar fields and a 2D vector field) simultaneously such that values can be accurately read using keys for all variables, a reasonable level of detail is shown, and important meteorological features stand out clearly. Our solution involves employing three perceptual "channels", a color channel, a texture channel, and a motion channel in order to perceptually separate the variables and make them independently readable. We conducted an experiment to evaluate our new design both against a conventional solution, and against a glyph-based solution. The evaluation tested the abilities of novice subjects both to read values using a key, and to see meteorological patterns in the data. Our new scheme was superior especially in the representation of wind patterns using the motion channel, and it also performed well enough in the representation of pressure using the texture channel to suggest it as a viable design alternative.

  14. Irradiation from video display terminals

    International Nuclear Information System (INIS)

    Backe, S.; Hannevik, M.

    1987-01-01

    Video display terminals (VDT's) are in common use by computer operators. In the last years this group of workers has expressed growing concern about their work environment and possible hazardious effects in connection with radiation emission from VDT's. Radiation types and levels of emission and possible biological effects have been the subject of research activity in Norway and in other countries. This report summarizes the various radiation types and their levels of emission from VDT's. An overview of recent epidemiological studies and animal experiments, and the conclusions given by the research groups are also presented. The conclusions drawn in this report based on the current knowledge are: Radiation, other than low frequency pulsed magnetic fields, have low and negligible emission levels and will not represent any health hazard to VDT-operator or to the foetus of pregnant operators. The biological effects of low frequency pulsed mangetic fields have been the subject of epidemiological studies and animal experiments. Epidemiological studies carried out in Canada, Finland, Sweden and Norway gave no support for any correlation between pregnancy complications and operation of VDT's. From animal experiments it has so far been impossible to assert an effect on pregnancy outcome from low frequency pulsed magnetic fields

  15. Citizenship displayed by disabled people

    Directory of Open Access Journals (Sweden)

    Eliana Prado Carlino

    2010-12-01

    Full Text Available By investigating the processes by which successful teachers become activate citizens and by listening to the diversity and richness of their life and formation stories, this work became possible. Its aim is to display some of the utterances of two Down Syndrome individuals and their active-citizenship activities. Their stories were told in the reports of two teachers when describing their personal and professional history, and were considered to be an integral part of it. Thus, some of the utterances and perceptions with which these two individuals elaborate their references, their worldview and their active-citizenship activity are evidenced in this paper. This article is based on the language conceptions of Vygotsky and Bakhtin who defend the idea that the group and the social mentality are ingrain in the individual. Hence, the history of one person reveals that of many others, since there is a deep link between the individual and the social in the formation of a subjective worldview. As a result, it can be easily seen that the utterances expressed by the participants in this research cannot be considered strictly individual because enunciation is social in nature. Despite the fact that the utterances are those of individuals, they manifest a collective reality. This demonstrates the real advantages and possibilities that deficient people get from their participation and intervention in society.

  16. CERN students display their work

    CERN Multimedia

    Anaïs Schaeffer

    2011-01-01

    The first poster session by students working on the LHC experiments, organised by the LPCC, was a great success. Showcasing the talents of over a hundred young physicists from all over the world, it was an opportunity for everyone at CERN to check out the wide range of research work being done by the new generation of physicists at CERN.   At 5.30 p.m. on Wednesday 23 March, the first poster session by CERN students took place in Restaurant No.1, where no fewer than 87 posters went on public display. The students were split into 8 groups according to their research field* and all were on hand to answer the questions of an inquisitive audience. TH Department's Michelangelo Mangano, who is head of the LHC Physics Centre at CERN (LPCC) and is responsible for the initiative, confirms that nothing was left to chance, even the choice of date: "We wanted to make the most of the general enthusiasm around the winter conferences and the meeting of the LHC Experiments Committee to present the stud...

  17. Hepatocytes Determine the Hypoxic Microenvironment and Radiosensitivity of Colorectal Cancer Cells Through Production of Nitric Oxide That Targets Mitochondrial Respiration

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Heng; Verovski, Valeri N.; Leonard, Wim; Law, Ka Lun; Vermeersch, Marieke; Storme, Guy; Van den Berge, Dirk; Gevaert, Thierry; Sermeus, Alexandra [Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels (Belgium); De Ridder, Mark, E-mail: mark.deridder@uzbrussel.be [Department of Radiotherapy, Universitair Ziekenhuis Brussel, Vrije Universiteit Brussel, Brussels (Belgium)

    2013-03-01

    Purpose: To determine whether host hepatocytes may reverse hypoxic radioresistance through nitric oxide (NO)-induced oxygen sparing, in a model relevant to colorectal cancer (CRC) liver metastases. Methods and Materials: Hepatocytes and a panel of CRC cells were incubated in a tissue-mimetic coculture system with diffusion-limited oxygenation, and oxygen levels were monitored by an oxygen-sensing fluorescence probe. To activate endogenous NO production, cocultures were exposed to a cytokine mixture, and the expression of inducible nitric oxide synthase was analyzed by reverse transcription–polymerase chain reaction, Western blotting, and NO/nitrite production. The mitochondrial targets of NO were examined by enzymatic activity. To assess hypoxic radioresponse, cocultures were irradiated and reseeded for colonies. Results: Resting hepatocytes consumed 10-40 times more oxygen than mouse CT26 and human DLD-1, HT29, HCT116, and SW480 CRC cells, and thus seemed to be the major effectors of hypoxic conditioning. As a result, hepatocytes caused uniform radioprotection of tumor cells at a 1:1 ratio. Conversely, NO-producing hepatocytes radiosensitized all CRC cell lines more than 1.5-fold, similar to the effect of selective mitochondrial inhibitors. The radiosensitizing effect was associated with a respiratory self-arrest of hepatocytes at the level of aconitase and complex II, which resulted in profound reoxygenation of tumor cells through oxygen sparing. Nitric oxide–producing hepatocytes were at least 10 times more active than NO-producing macrophages to reverse hypoxia-induced radioresistance. Conclusions: Hepatocytes were the major determinants of the hypoxic microenvironment and radioresponse of CRC cells in our model of metabolic hypoxia. We provide evidence that reoxygenation and radiosensitization of hypoxic CRC cells can be achieved through oxygen sparing induced by endogenous NO production in host hepatocytes.

  18. Protective effects of melittin on transforming growth factor-β1 injury to hepatocytes via anti-apoptotic mechanism

    International Nuclear Information System (INIS)

    Lee, Woo-Ram; Park, Ji-Hyun; Kim, Kyung-Hyun; Park, Yoon-Yub; Han, Sang-Mi; Park, Kwan-kyu

    2011-01-01

    Melittin is a cationic, hemolytic peptide that is the main toxic component in the venom of the honey bee (Apis mellifera). Melittin has multiple effects, including anti-bacterial, anti-viral and anti-inflammatory, in various cell types. However, the anti-apoptotic mechanisms of melittin have not been fully elucidated in hepatocytes. Apoptosis contributes to liver inflammation and fibrosis. Knowledge of the apoptotic mechanisms is important to develop new and effective therapies for treatment of cirrhosis, portal hypertension, liver cancer, and other liver diseases. In the present study, we investigated the anti-apoptotic effect of melittin on transforming growth factor (TGF)-β1-induced apoptosis in hepatocytes. TGF-β1-treated hepatocytes were exposed to low doses (0.5 and 1 μg/mL) and high dose (2 μg/mL) of melittin. The low doses significantly protected these cells from DNA damage in TGF-β1-induced apoptosis compared to the high dose. Also, melittin suppressed TGF-β1-induced apoptotic activation of the Bcl-2 family and caspase family of proteins, which resulted in the inhibition of poly-ADP-ribose polymerase (PARP) cleavage. These results demonstrate that TGF-β1 induces hepatocyte apoptosis and that an optimal dose of melittin exerts anti-apoptotic effects against TGF-β1-induced injury to hepatocytes via the mitochondrial pathway. These results suggest that an optimal dose of melittin can serve to protect cells against TGF-β1-mediated injury. - Highlights: → We investigated the anti-apoptotic effect of melittin on TGF-β1-induced hepatocyte. → TGF-β1 induces hepatocyte apoptosis. → TGF-β1-treated hepatocytes were exposed to low doses and high dose of melittin. → Optimal dose of melittin exerts anti-apoptotic effects to hepatocytes.

  19. AR42J-B-13 cell: An expandable progenitor to generate an unlimited supply of functional hepatocytes

    International Nuclear Information System (INIS)

    Wallace, Karen; Fairhall, Emma A.; Charlton, Keith A.; Wright, Matthew C.

    2010-01-01

    Hepatocytes are the preparation of choice for Toxicological research in vitro. However, despite the fact that hepatocytes proliferate in vivo during liver regeneration, they are resistant to proliferation in vitro, do not tolerate sub-culture and tend to enter a de-differentiation program that results in a loss of hepatic function. These limitations have resulted in the search for expandable rodent and human cells capable of being directed to differentiate into functional hepatocytes. Research with stem cells suggests that it may be possible to provide the research community with hepatocytes in vitro although to date, significant challenges remain, notably generating a sufficiently pure population of hepatocytes with a quantitative functionality comparable with hepatocytes. This paper reviews work with the AR42J-B-13 (B-13) cell line. The B-13 cell was cloned from the rodent AR42J pancreatic cell line, express genes associated with pancreatic acinar cells and readily proliferates in simple culture media. When exposed to glucocorticoid, 75-85% of the cells trans-differentiate into hepatocyte-like (B-13/H) cells functioning at a level quantitatively similar to freshly isolated rat hepatocytes (with the remaining cells retaining the B-13 phenotype). Trans-differentiation of pancreatic acinar cells also appears to occur in vivo in rats treated with glucocorticoid; in mice with elevated circulating glucocorticoid and in humans treated for long periods with glucocorticoid. The B-13 response to glucocorticoid therefore appears to be related to a real pathophysiological response of a pancreatic cell to glucocorticoid. An understanding of how this process occurs and if it can be generated or engineered in human cells would result in a cell line with the ability to generate an unlimited supply of functional human hepatocytes in a cost effective manner.

  20. Hepatocytes Determine the Hypoxic Microenvironment and Radiosensitivity of Colorectal Cancer Cells Through Production of Nitric Oxide That Targets Mitochondrial Respiration

    International Nuclear Information System (INIS)

    Jiang, Heng; Verovski, Valeri N.; Leonard, Wim; Law, Ka Lun; Vermeersch, Marieke; Storme, Guy; Van den Berge, Dirk; Gevaert, Thierry; Sermeus, Alexandra; De Ridder, Mark

    2013-01-01

    Purpose: To determine whether host hepatocytes may reverse hypoxic radioresistance through nitric oxide (NO)-induced oxygen sparing, in a model relevant to colorectal cancer (CRC) liver metastases. Methods and Materials: Hepatocytes and a panel of CRC cells were incubated in a tissue-mimetic coculture system with diffusion-limited oxygenation, and oxygen levels were monitored by an oxygen-sensing fluorescence probe. To activate endogenous NO production, cocultures were exposed to a cytokine mixture, and the expression of inducible nitric oxide synthase was analyzed by reverse transcription–polymerase chain reaction, Western blotting, and NO/nitrite production. The mitochondrial targets of NO were examined by enzymatic activity. To assess hypoxic radioresponse, cocultures were irradiated and reseeded for colonies. Results: Resting hepatocytes consumed 10-40 times more oxygen than mouse CT26 and human DLD-1, HT29, HCT116, and SW480 CRC cells, and thus seemed to be the major effectors of hypoxic conditioning. As a result, hepatocytes caused uniform radioprotection of tumor cells at a 1:1 ratio. Conversely, NO-producing hepatocytes radiosensitized all CRC cell lines more than 1.5-fold, similar to the effect of selective mitochondrial inhibitors. The radiosensitizing effect was associated with a respiratory self-arrest of hepatocytes at the level of aconitase and complex II, which resulted in profound reoxygenation of tumor cells through oxygen sparing. Nitric oxide–producing hepatocytes were at least 10 times more active than NO-producing macrophages to reverse hypoxia-induced radioresistance. Conclusions: Hepatocytes were the major determinants of the hypoxic microenvironment and radioresponse of CRC cells in our model of metabolic hypoxia. We provide evidence that reoxygenation and radiosensitization of hypoxic CRC cells can be achieved through oxygen sparing induced by endogenous NO production in host hepatocytes

  1. Efficient derivation of functional hepatocytes from mouse induced pluripotent stem cells by a combination of cytokines and sodium butyrate

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qi; YANG Yang; ZHANG Jian; WANG Guo-ying; LIU Wei; QIU Dong-bo; HEI Zi-qing; YING Qi-long; CHEN Gui-hua

    2011-01-01

    Background Hepatocyte transplantation has been proposed as an alternative to whole-organ transplantation to support many forms of hepatic insufficiency.Unfortunately,the lack of donor livers makes it difficult to obtain enough viable human hepatocytes for hepatocyte-based therapies.Therefore,it is urgent to find new ways to provide ample hepatocytes.Induced pluripotent stem (iPS) cells,a breakthrough in stem cell research,may terminate these hinders for cell transplantation.For the promise of iPS cells to be realized in liver diseases,it is necessary to determine if and how efficient they can be differentiated into functional hepatocytes.Methods In this study,we directly compared the hepatic-differentiation capacity of mouse iPS cells and embryonic stem (ES) cells with three different induction approaches:conditions via embryonic body (EB) formation plus cytokines,conditions by combination of dimethyl sulfoxide and sodium butyrate and chemically defined,serum free monolayer conditions.Among these three induction conditions,more homogenous populations can be promoted under chemically defined,serum free conditions.The cells generated under these conditions exhibited hepatic functions in vitro,including glycogen storage,indocynine green (ICG) uptake and release as well as urea secretion.Although efficient hepatocytes differentiation from mouse iPS cells were observed,mouse iPS cells showed relatively lower hepatic induction efficiency compared with mouse ES cells.Results Mouse iPS cells would be efficiently differentiated into functional hepatocytes in vitro,which may be helpful in facilitating the development of hepatocytes for transplantation and for research on drug discovery.Conclusion We demonstrate that mouse iPS cells retain full potential for fetal liver development and describe procedures that facilitates the efficient generation of highly differentiated human hepatocyte-like cells from iPS cells in vitro.

  2. Efficient Generation of Functional Hepatocytes From Human Embryonic Stem Cells and Induced Pluripotent Stem Cells by HNF4α Transduction

    OpenAIRE

    Takayama, Kazuo; Inamura, Mitsuru; Kawabata, Kenji; Katayama, Kazufumi; Higuchi, Maiko; Tashiro, Katsuhisa; Nonaka, Aki; Sakurai, Fuminori; Hayakawa, Takao; Kusuda Furue, Miho; Mizuguchi, Hiroyuki

    2012-01-01

    Hepatocyte-like cells from human embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) are expected to be a useful source of cells drug discovery. Although we recently reported that hepatic commitment is promoted by transduction of SOX17 and HEX into human ESC- and iPSC-derived cells, these hepatocyte-like cells were not sufficiently mature for drug screening. To promote hepatic maturation, we utilized transduction of the hepatocyte nuclear factor 4α (HNF4α) gene, which is kn...

  3. The effect of display movement angle, indicator type and display location on control/display stereotype strength.

    Science.gov (United States)

    Hoffmann, Errol R; Chan, Alan H S

    2017-08-01

    Much research on stereotype strength relating display and control movements for displays moving in the vertical or horizontal directions has been reported. Here we report effects of display movement angle, where the display moves at angles (relative to the vertical) of between 0° and 180°. The experiment used six different controls, four display locations relative to the operator and three types of indicator. Indicator types were included because of the strong effects of the 'scale-side principle' that are variable with display angle. A directional indicator had higher stereotype strength than a neutral indicator, and showed an apparent reversal in control/display stereotype direction beyond an angle of 90°. However, with a neutral indicator this control reversal was not present. Practitioner Summary: The effects of display moving at angles other than the four cardinal directions, types of control, location of display and types of indicator are investigated. Indicator types (directional and neutral) have an effect on stereotype strength and may cause an apparent control reversal with change of display movement angle.

  4. Conceptual Design of Industrial Process Displays

    DEFF Research Database (Denmark)

    Pedersen, C.R.; Lind, Morten

    1999-01-01

    discusses aspects of process display design taking into account both the designer's and the operator's points of view. Three aspects are emphasized: the operator tasks, the display content and the display form. The distinction between these three aspects is the basis for proposing an outline for a display......Today, process displays used in industry are often designed on the basis of piping and instrumentation diagrams without any method of ensuring that the needs of the operators are fulfilled. Therefore, a method for a systematic approach to the design of process displays is needed. This paper...... by a simple example from a plant with batch processes. Later the method is applied to develop a supervisory display for a condenser system in a nuclear power plant. The differences between the continuous plant domain of power production and the batch processes from the example are analysed and broad...

  5. Acrolein cytotoxicity in hepatocytes involves endoplasmic reticulum stress, mitochondrial dysfunction and oxidative stress

    International Nuclear Information System (INIS)

    Mohammad, Mohammad K.; Avila, Diana; Zhang, Jingwen; Barve, Shirish; Arteel, Gavin; McClain, Craig; Joshi-Barve, Swati

    2012-01-01

    Acrolein is a common environmental, food and water pollutant and a major component of cigarette smoke. Also, it is produced endogenously via lipid peroxidation and cellular metabolism of certain amino acids and drugs. Acrolein is cytotoxic to many cell types including hepatocytes; however the mechanisms are not fully understood. We examined the molecular mechanisms underlying acrolein hepatotoxicity in primary human hepatocytes and hepatoma cells. Acrolein, at pathophysiological concentrations, caused a dose-dependent loss of viability of hepatocytes. The death was apoptotic at moderate and necrotic at high concentrations of acrolein. Acrolein exposure rapidly and dramatically decreased intracellular glutathione and overall antioxidant capacity, and activated the stress-signaling MAP-kinases JNK, p42/44 and p38. Our data demonstrate for the first time in human hepatocytes, that acrolein triggered endoplasmic reticulum (ER) stress and activated eIF2α, ATF-3 and -4, and Gadd153/CHOP, resulting in cell death. Notably, the protective/adaptive component of ER stress was not activated, and acrolein failed to up-regulate the protective ER-chaperones, GRP78 and GRP94. Additionally, exposure to acrolein disrupted mitochondrial integrity/function, and led to the release of pro-apoptotic proteins and ATP depletion. Acrolein-induced cell death was attenuated by N-acetyl cysteine, phenyl-butyric acid, and caspase and JNK inhibitors. Our data demonstrate that exposure to acrolein induces a variety of stress responses in hepatocytes, including GSH depletion, oxidative stress, mitochondrial dysfunction and ER stress (without ER-protective responses) which together contribute to acrolein toxicity. Our study defines basic mechanisms underlying liver injury caused by reactive aldehyde pollutants such as acrolein. -- Highlights: ► Human primary hepatocytes and cultured cell lines are used. ► Multiple cell death signaling pathways are activated by acrolein. ► Novel finding of

  6. Chronic alcohol feeding potentiates hormone-induced calcium signalling in hepatocytes.

    Science.gov (United States)

    Bartlett, Paula J; Antony, Anil Noronha; Agarwal, Amit; Hilly, Mauricette; Prince, Victoria L; Combettes, Laurent; Hoek, Jan B; Gaspers, Lawrence D

    2017-05-15

    Chronic alcohol consumption causes a spectrum of liver diseases, but the pathogenic mechanisms driving the onset and progression of disease are not clearly defined. We show that chronic alcohol feeding sensitizes rat hepatocytes to Ca 2+ -mobilizing hormones resulting in a leftward shift in the concentration-response relationship and the transition from oscillatory to more sustained and prolonged Ca 2+ increases. Our data demonstrate that alcohol-dependent adaptation in the Ca 2+ signalling pathway occurs at the level of hormone-induced inositol 1,4,5 trisphosphate (IP 3 ) production and does not involve changes in the sensitivity of the IP 3 receptor or size of internal Ca 2+ stores. We suggest that prolonged and aberrant hormone-evoked Ca 2+ increases may stimulate the production of mitochondrial reactive oxygen species and contribute to alcohol-induced hepatocyte injury. ABSTRACT: 'Adaptive' responses of the liver to chronic alcohol consumption may underlie the development of cell and tissue injury. Alcohol administration can perturb multiple signalling pathways including phosphoinositide-dependent cytosolic calcium ([Ca 2+ ] i ) increases, which can adversely affect mitochondrial Ca 2+ levels, reactive oxygen species production and energy metabolism. Our data indicate that chronic alcohol feeding induces a leftward shift in the dose-response for Ca 2+ -mobilizing hormones resulting in more sustained and prolonged [Ca 2+ ] i increases in both cultured hepatocytes and hepatocytes within the intact perfused liver. Ca 2+ increases were initiated at lower hormone concentrations, and intercellular calcium wave propagation rates were faster in alcoholics compared to controls. Acute alcohol treatment (25 mm) completely inhibited hormone-induced calcium increases in control livers, but not after chronic alcohol-feeding, suggesting desensitization to the inhibitory actions of ethanol. Hormone-induced inositol 1,4,5 trisphosphate (IP 3 ) accumulation and phospholipase C

  7. Acrolein cytotoxicity in hepatocytes involves endoplasmic reticulum stress, mitochondrial dysfunction and oxidative stress

    Energy Technology Data Exchange (ETDEWEB)

    Mohammad, Mohammad K. [Department of Medicine, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States); Avila, Diana [Department of Medicine, University of Louisville (United States); Department of Pharmacology and Toxicology, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States); Zhang, Jingwen [Department of Medicine, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States); Barve, Shirish [Department of Medicine, University of Louisville (United States); Department of Pharmacology and Toxicology, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States); Arteel, Gavin [Department of Pharmacology and Toxicology, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States); McClain, Craig [Department of Medicine, University of Louisville (United States); Department of Pharmacology and Toxicology, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States); Robley Rex VAMC, Louisville, KY (United States); Joshi-Barve, Swati, E-mail: s0josh01@louisville.edu [Department of Medicine, University of Louisville (United States); Department of Pharmacology and Toxicology, University of Louisville (United States); Alcohol Research Center, University of Louisville (United States)

    2012-11-15

    Acrolein is a common environmental, food and water pollutant and a major component of cigarette smoke. Also, it is produced endogenously via lipid peroxidation and cellular metabolism of certain amino acids and drugs. Acrolein is cytotoxic to many cell types including hepatocytes; however the mechanisms are not fully understood. We examined the molecular mechanisms underlying acrolein hepatotoxicity in primary human hepatocytes and hepatoma cells. Acrolein, at pathophysiological concentrations, caused a dose-dependent loss of viability of hepatocytes. The death was apoptotic at moderate and necrotic at high concentrations of acrolein. Acrolein exposure rapidly and dramatically decreased intracellular glutathione and overall antioxidant capacity, and activated the stress-signaling MAP-kinases JNK, p42/44 and p38. Our data demonstrate for the first time in human hepatocytes, that acrolein triggered endoplasmic reticulum (ER) stress and activated eIF2α, ATF-3 and -4, and Gadd153/CHOP, resulting in cell death. Notably, the protective/adaptive component of ER stress was not activated, and acrolein failed to up-regulate the protective ER-chaperones, GRP78 and GRP94. Additionally, exposure to acrolein disrupted mitochondrial integrity/function, and led to the release of pro-apoptotic proteins and ATP depletion. Acrolein-induced cell death was attenuated by N-acetyl cysteine, phenyl-butyric acid, and caspase and JNK inhibitors. Our data demonstrate that exposure to acrolein induces a variety of stress responses in hepatocytes, including GSH depletion, oxidative stress, mitochondrial dysfunction and ER stress (without ER-protective responses) which together contribute to acrolein toxicity. Our study defines basic mechanisms underlying liver injury caused by reactive aldehyde pollutants such as acrolein. -- Highlights: ► Human primary hepatocytes and cultured cell lines are used. ► Multiple cell death signaling pathways are activated by acrolein. ► Novel finding of

  8. Intracellular cholesterol-binding proteins enhance HDL-mediated cholesterol uptake in cultured primary mouse hepatocytes.

    Science.gov (United States)

    Storey, Stephen M; McIntosh, Avery L; Huang, Huan; Landrock, Kerstin K; Martin, Gregory G; Landrock, Danilo; Payne, H Ross; Atshaves, Barbara P; Kier, Ann B; Schroeder, Friedhelm

    2012-04-15

    A major gap in our knowledge of rapid hepatic HDL cholesterol clearance is the role of key intracellular factors that influence this process. Although the reverse cholesterol transport pathway targets HDL to the liver for net elimination of free cholesterol from the body, molecular details governing cholesterol uptake into hepatocytes are not completely understood. Therefore, the effects of sterol carrier protein (SCP)-2 and liver fatty acid-binding protein (L-FABP), high-affinity cholesterol-binding proteins present in hepatocyte cytosol, on HDL-mediated free cholesterol uptake were examined using gene-targeted mouse models, cultured primary hepatocytes, and 22-[N-(7-nitrobenz-2-oxa-1,3-diazol-4-yl)-amino]-23,24-bisnor-5-cholen-3β-ol (NBD-cholesterol). While SCP-2 overexpression enhanced NBD-cholesterol uptake, counterintuitively, SCP-2/SCP-x gene ablation also 1) enhanced the rapid molecular phase of free sterol uptake detectable in rate and maximal uptake of HDL free cholesterol and 2) differentially enhanced free cholesterol uptake mediated by the HDL3, rather than the HDL2, subfraction. The increased HDL free cholesterol uptake was not due to increased expression or distribution of the HDL receptor [scavenger receptor B1 (SRB1)], proteins regulating SRB1 [postsynaptic density protein (PSD-95)/Drosophila disk large tumor suppressor (dlg)/tight junction protein (ZO1) and 17-kDa membrane-associated protein], or other intracellular cholesterol trafficking proteins (steroidogenic acute response protein D, Niemann Pick C, and oxysterol-binding protein-related proteins). However, expression of L-FABP, the single most prevalent hepatic cytosolic protein that binds cholesterol, was upregulated twofold in SCP-2/SCP-x null hepatocytes. Double-immunogold electron microscopy detected L-FABP sufficiently close to SRB1 for direct interaction, similar to SCP-2. These data suggest a role for L-FABP in HDL cholesterol uptake, a finding confirmed with SCP-2/SCP-x/L-FABP null

  9. In Vitro Rat Hepatocyte Toxicity and Bacteria Genotoxicity Evaluation of High Energy Chemicals for Replacement of Hydrazine

    National Research Council Canada - National Science Library

    Husain, S

    2002-01-01

    In an effort to develop methods to predict the toxicological response of newly synthesized chemicals that are of interest to the US Air Force, in vitro rat hepatocyte toxicity and bacteria (Salmonella...

  10. Interleukin-1 inhibition facilitates recovery from liver injury and promotes regeneration of hepatocytes in alcoholic hepatitis in mice.

    Science.gov (United States)

    Iracheta-Vellve, Arvin; Petrasek, Jan; Gyogyosi, Benedek; Bala, Shashi; Csak, Timea; Kodys, Karen; Szabo, Gyongyi

    2017-07-01

    Inflammation and impaired hepatocyte regeneration contribute to liver failure in alcoholic hepatitis (AH). Interleukin (IL)-1 is a key inflammatory cytokine in the pathobiology of AH. The role of IL-1 in liver regeneration in the recovery phase of alcohol-induced liver injury is unknown. In this study, we tested IL-1 receptor antagonist to block IL-1 signalling in a mouse model of acute-on-chronic liver injury on liver inflammation and hepatocyte regeneration in AH. We observed that inhibition of IL-1 signalling decreased liver inflammation and neutrophil infiltration, and resulted in enhanced regeneration of hepatocytes and increased rate of recovery from liver injury in AH. Our novel findings suggest that IL-1 drives sustained liver inflammation and impaired hepatocyte regeneration even after cessation of ethanol exposure. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  11. Basics of Antibody Phage Display Technology.

    Science.gov (United States)

    Ledsgaard, Line; Kilstrup, Mogens; Karatt-Vellatt, Aneesh; McCafferty, John; Laustsen, Andreas H

    2018-06-09

    Antibody discovery has become increasingly important in almost all areas of modern medicine. Different antibody discovery approaches exist, but one that has gained increasing interest in the field of toxinology and antivenom research is phage display technology. In this review, the lifecycle of the M13 phage and the basics of phage display technology are presented together with important factors influencing the success rates of phage display experiments. Moreover, the pros and cons of different antigen display methods and the use of naïve versus immunized phage display antibody libraries is discussed, and selected examples from the field of antivenom research are highlighted. This review thus provides in-depth knowledge on the principles and use of phage display technology with a special focus on discovery of antibodies that target animal toxins.

  12. Three-dimensional Imaging, Visualization, and Display

    CERN Document Server

    Javidi, Bahram; Son, Jung-Young

    2009-01-01

    Three-Dimensional Imaging, Visualization, and Display describes recent developments, as well as the prospects and challenges facing 3D imaging, visualization, and display systems and devices. With the rapid advances in electronics, hardware, and software, 3D imaging techniques can now be implemented with commercially available components and can be used for many applications. This volume discusses the state-of-the-art in 3D display and visualization technologies, including binocular, multi-view, holographic, and image reproduction and capture techniques. It also covers 3D optical systems, 3D display instruments, 3D imaging applications, and details several attractive methods for producing 3D moving pictures. This book integrates the background material with new advances and applications in the field, and the available online supplement will include full color videos of 3D display systems. Three-Dimensional Imaging, Visualization, and Display is suitable for electrical engineers, computer scientists, optical e...

  13. Data display with the Q system

    International Nuclear Information System (INIS)

    Oothoudt, M.A.

    1979-01-01

    The Q data-acquisition system for PDP-11 mini-computers at the Clinton P. Anderson Meson Physics Facility (LAMPF) provides experimenters with basic tools for on-line data display. Tasks are available to plot one- and two-parameter histograms on Tektronix 4000 series storage-tube terminals. The histograms to be displayed and the display format may be selected with simple keyboard commands. A task is also available to create and display live two-parameter scatter plots for any acquired or calculated quantities. Other tasks in the system manage the display data base, list display parameters and histogram contents on hardcopy devices, and save core histograms on disk or tape for off-line analysis. 8 figures

  14. Effect of display size on visual attention.

    Science.gov (United States)

    Chen, I-Ping; Liao, Chia-Ning; Yeh, Shih-Hao

    2011-06-01

    Attention plays an important role in the design of human-machine interfaces. However, current knowledge about attention is largely based on data obtained when using devices of moderate display size. With advancement in display technology comes the need for understanding attention behavior over a wider range of viewing sizes. The effect of display size on test participants' visual search performance was studied. The participants (N = 12) performed two types of visual search tasks, that is, parallel and serial search, under three display-size conditions (16 degrees, 32 degrees, and 60 degrees). Serial, but not parallel, search was affected by display size. In the serial task, mean reaction time for detecting a target increased with the display size.

  15. Differential effects of omeprazole and lansoprazole enantiomers on aryl hydrocarbon receptor in human hepatocytes and cell lines.

    Science.gov (United States)

    Novotna, Aneta; Srovnalova, Alzbeta; Svecarova, Michaela; Korhonova, Martina; Bartonkova, Iveta; Dvorak, Zdenek

    2014-01-01

    Proton pump inhibitors omeprazole and lansoprazole contain chiral sulfur atom and they are administered as a racemate, i.e. equimolar mixture of S- and R-enantiomers. The enantiopure drugs esomeprazole and dexlansoprazole have been developed and introduced to clinical practice due to their improved clinical and therapeutic properties. Since omeprazole and lansoprazole are activators of aryl hydrocarbon receptor (AhR) and inducers of CYP1A genes, we examined their enantiospecific effects on AhR-CYP1A pathway in human cancer cells and primary human hepatocytes. We performed gene reporter assays for transcriptional activity of AhR, RT-PCR analyses for CYP1A1/2 mRNAs, western blots for CYP1A1/2 proteins and EROD assay for CYP1A1/2 catalytic activity. Lansoprazole and omeprazole enantiomers displayed differential effects on AhR-CYP1A1/2 pathway. In general, S-enantiomers were stronger activators of AhR and inducers of CYP1A genes as compared to R-enantiomers in lower concentrations, i.e. 1-10 µM for lansoprazole and 10-100 µM for omeprazole. In contrast, R-enantiomers were stronger AhR activators and CYP1A inducers than S-enantiomers in higher concentrations, i.e. 100 µM for lansoprazole and 250 µM for omeprazole. In conclusion, we provide the first evidence of enantiospecific effects of omeprazole and lansoprazole on AhR signaling pathway.

  16. Helmet-Mounted Display Design Guide

    Science.gov (United States)

    1997-11-03

    on openStack create menu "CSHMD" set the menuitems of "CSHMD" to "(Main Menu; References;-; Definitions;Display Criteria;Display Formats;Display Modes...34Macintosh" then put ":" into dirSep else put "V’ into dirSep put stackPathO&"Resource"&dirSep into gResPath put 0 into gXRef end openStack on

  17. Method for control-room display design

    International Nuclear Information System (INIS)

    Montmayeul, R.

    1988-01-01

    This document describes a method for control-room displays design. It can be used either for isolated display to add to an existing system either for the design of a full system of operator aids. The method is a top-down design with steps of possible iteration. The emphasis is put on display design rather than on system design; system aspects are just mentioned. Advantages of using a method are described [fr

  18. Optimizing direct response in Internet display advertising

    OpenAIRE

    Aksakallı, Vural

    2013-01-01

    Internet display advertising has grown into a multi-billion dollar a year global industry and direct response campaigns account for about three-quarters of all Internet display advertising. In such campaigns, advertisers reach out to a target audience via some form of a visual advertisement (hereinafter also called “ad”) to maximize short-term sales revenue. In this study, we formulate an advertiser’s revenue maximization problem in direct response Internet display advertisement campaigns as ...

  19. Manufacturing considerations for AMLCD cockpit displays

    Science.gov (United States)

    Luo, Fang-Chen

    1995-06-01

    AMLCD cockpit displays need to meet more stringent requirements compared with AMLCD commercial displays in areas such as environmental conditions, optical performance and device reliability. Special considerations are required for the manufacturing of AMLCD cockpit displays in each process step to address these issues. Some examples are: UV stable polarizers, wide-temperature LC material, strong LC glue seal, ESS test system, gray scale voltage EEPROM, etc.

  20. Online Display Advertising Causal Attribution and Evaluation

    OpenAIRE

    Barajas Zamora, Joel

    2015-01-01

    The allocation of a given budget to online display advertising as a marketing channel has motivated the development of statistical methods to measure its effectiveness. Recent studies show that display advertising often triggers online users to search for more information on products. Eventually, many of these users convert at the advertiser’s website. A key challenge is to measure the effectiveness of display advertising when users are exposed to multiple unknown advertising channels.We deve...

  1. Statistical Arbitrage Mining for Display Advertising

    OpenAIRE

    Zhang, Weinan; Wang, Jun

    2015-01-01

    We study and formulate arbitrage in display advertising. Real-Time Bidding (RTB) mimics stock spot exchanges and utilises computers to algorithmically buy display ads per impression via a real-time auction. Despite the new automation, the ad markets are still informationally inefficient due to the heavily fragmented marketplaces. Two display impressions with similar or identical effectiveness (e.g., measured by conversion or click-through rates for a targeted audience) may sell for quite diff...

  2. Endocrine disruption screening by protein and gene expression of vitellogenin in freshly isolated and cryopreserved rainbow trout hepatocytes.

    Science.gov (United States)

    Markell, Lauren K; Mingoia, Robert T; Peterson, Heather M; Yao, Jianhong; Waters, Stephanie M; Finn, James P; Nabb, Diane L; Han, Xing

    2014-08-18

    Xenobiotics may activate the estrogen receptor, resulting in alteration of normal endocrine functions in animals and humans. Consequently, this necessitates development of assay end points capable of identifying estrogenic xenobiotics. In the present study, we screened the potential estrogenicity of chemicals via their ability to induce vitellogenin (VTG) expression in cultured primary hepatocytes from male trout. A routine method for VTG detection measures the secretion of the protein by enzyme-linked immunosorbent assay (ELISA) in freshly isolated trout hepatocytes. However, this lengthy (6 days) culturing procedure requires that hepatocyte isolation is performed each time the assay is run. We optimized this methodology by investigating the utility of cryopreserved hepatocytes, shortening the incubation time, performing a quantitative real-time PCR (qPCR) method for VTG quantification, and verifying the model system with reference chemicals 17β-estradiol, estrone, diethylstilbestrol, hexestrol, genistein, and a negative control, corticosterone. To test the performance of both freshly isolated and cryopreserved hepatocytes, mRNA was collected from hepatocytes following 24 h treatment for VTG gene expression analysis, whereas cell culture media was collected for a VTG ELISA 96 h post-treatment. EC50 values were obtained for each reference chemical except for corticosterone, which exhibited no induction of VTG gene or protein level. Our results show linear concordance between ELISA and qPCR detection methods. Although there was approximately 50% reduction in VTG inducibility following cryopreservation, linear concordance of EC50 values was found between freshly isolated and cryopreserved hepatocytes, indicating that cryopreservation does not alter the functional assessment of estrogen receptor activation and therefore VTG expression. These studies demonstrate that qPCR is a sensitive and specific method for detecting VTG gene expression that can be used together

  3. Hydrodynamic Delivery of Cre Protein to Lineage-Mark or Time-Stamp Mouse Hepatocytes In situ

    Science.gov (United States)

    Sonsteng, Katherine M.; Prigge, Justin R.; Talago, Emily A.; June, Ronald K.; Schmidt, Edward E.

    2014-01-01

    Cre-responsive fluorescent marker alleles are powerful tools for cell lineage tracing in mice; however their utility is limited by regulation of Cre activity. When targeting hepatocytes, hydrodynamic delivery of a Cre-expression plasmid can convert Cre-responsive alleles without inducing the intracellular or systemic antiviral responses often associated with viral-derived Cre-expression vectors. In this method, rapid high-volume intravenous inoculation induces hepatocyte-targeted uptake of extracellular molecules. Here we tested whether hydrodynamic delivery of Cre protein or Cre fused to the HIV-TAT cell-penetrating peptide could convert Cre-responsive reporters in hepatocytes of mice. Hydrodynamic delivery of 2 nmol of either Cre or TAT-Cre protein converted the reporter allele in 5 to 20% of hepatocytes. Neither protein gave detectable Cre activity in endothelia, non-liver organs, or non-hepatocyte cells in liver. Using mice homozygous for a Cre-responsive marker that directs red- (Cre-naïve) or green- (Cre-converted) fluorescent proteins to the nucleus, we assessed sub-saturation Cre-activity. One month after hydrodynamic inoculation with Cre protein, 58% of hepatocyte nuclei that were green were also red, indicating that less than half of the hepatocytes that had obtained enough Cre to convert one marker allele to green were able to convert all alleles. For comparison, one month after hydrodynamic delivery of a Cre-expression plasmid with a weak promoter, only 26% of the green nuclei were also red. Our results show that hydrodynamic delivery of Cre protein allows rapid allelic conversion in hepatocytes, but Cre-activity is sub-saturating so many cells will not convert multiple Cre-responsive alleles. PMID:24626158

  4. Energy Awareness Displays - Making the Invisible Visible

    NARCIS (Netherlands)

    Börner, Dirk

    2011-01-01

    Börner, D. (2011). Energy Awareness Displays - Making the Invisible Visible. Presentation given at the Startbijeenkomst SURFnet Innovatieregeling Duurzaamheid & ICT. May, 13, 2011, Utrecht, The Netherlands.

  5. Refreshable Braille displays using EAP actuators

    Science.gov (United States)

    Bar-Cohen, Yoseph

    2010-04-01

    Refreshable Braille can help visually impaired persons benefit from the growing advances in computer technology. The development of such displays in a full screen form is a great challenge due to the need to pack many actuators in small area without interferences. In recent years, various displays using actuators such as piezoelectric stacks have become available in commercial form but most of them are limited to one line Braille code. Researchers in the field of electroactive polymers (EAP) investigated methods of using these materials to form full screen displays. This manuscript reviews the state of the art of producing refreshable Braille displays using EAP-based actuators.

  6. NCAP projection displays: key issues for commercialization

    Science.gov (United States)

    Tomita, Akira; Jones, Philip J.

    1992-06-01

    Recently there has been much interest in a new polymer nematic dispersion technology, often called as NCAP, PDLC, PNLC, LCPC, etc., since projection displays using this technology have been shown to produce much brighter display images than projectors using conventional twisted nematic (TN) lightvalves. For commercializing projection displays based on this polymer nematic dispersion technology, the new materials must not only meet various electro- optic requirements, e.g., operational voltage, `off-state'' scattering angle, voltage holding ratio and hysteresis, but must also be stable over the lifetime of the product. This paper reports recent progress in the development of NCAP based projection displays and discusses some of the key commercialization issues.

  7. New ultraportable display technology and applications

    Science.gov (United States)

    Alvelda, Phillip; Lewis, Nancy D.

    1998-08-01

    MicroDisplay devices are based on a combination of technologies rooted in the extreme integration capability of conventionally fabricated CMOS active-matrix liquid crystal display substrates. Customized diffraction grating and optical distortion correction technology for lens-system compensation allow the elimination of many lenses and systems-level components. The MicroDisplay Corporation's miniature integrated information display technology is rapidly leading to many new defense and commercial applications. There are no moving parts in MicroDisplay substrates, and the fabrication of the color generating gratings, already part of the CMOS circuit fabrication process, is effectively cost and manufacturing process-free. The entire suite of the MicroDisplay Corporation's technologies was devised to create a line of application- specific integrated circuit single-chip display systems with integrated computing, memory, and communication circuitry. Next-generation portable communication, computer, and consumer electronic devices such as truly portable monitor and TV projectors, eyeglass and head mounted displays, pagers and Personal Communication Services hand-sets, and wristwatch-mounted video phones are among the may target commercial markets for MicroDisplay technology. Defense applications range from Maintenance and Repair support, to night-vision systems, to portable projectors for mobile command and control centers.

  8. Microencapsulated Electrophoretic Films for Electronic Paper Displays

    Science.gov (United States)

    Amundson, Karl

    2003-03-01

    Despite the dominance of liquid crystal displays, they do not perform some functions very well. While backlit liquid crystal displays can offer excellent color performance, they wash out in bright lighting and suffer from high power consumption. Reflective liquid crystal displays have limited brightness, making these devices challenging to read for long periods of time. Flexible liquid crystal displays are difficult to manufacture and keep stable. All of these attributes (long battery lifetime, bright reflective appearance, compatibility with flexible substrates) are traits that would be found in an ideal electronic paper display - an updateable substitute for paper that could be employed in electronic books, newspapers, and other applications. I will discuss technologies that are being developed for electronic-paper-like displays, and especially on particle-based technologies. A microencapsulated electrophoretic display technology is being developed at the E Ink corporation. This display film offers offer high brightness and an ink-on-paper appearance, compatibility with flexible substrates, and image stability that can lead to very low power consumption. I will present some of the physical and chemical challenges associated with making display films with high performance.

  9. Exploring interaction with 3D volumetric displays

    Science.gov (United States)

    Grossman, Tovi; Wigdor, Daniel; Balakrishnan, Ravin

    2005-03-01

    Volumetric displays generate true volumetric 3D images by actually illuminating points in 3D space. As a result, viewing their contents is similar to viewing physical objects in the real world. These displays provide a 360 degree field of view, and do not require the user to wear hardware such as shutter glasses or head-trackers. These properties make them a promising alternative to traditional display systems for viewing imagery in 3D. Because these displays have only recently been made available commercially (e.g., www.actuality-systems.com), their current use tends to be limited to non-interactive output-only display devices. To take full advantage of the unique features of these displays, however, it would be desirable if the 3D data being displayed could be directly interacted with and manipulated. We investigate interaction techniques for volumetric display interfaces, through the development of an interactive 3D geometric model building application. While this application area itself presents many interesting challenges, our focus is on the interaction techniques that are likely generalizable to interactive applications for other domains. We explore a very direct style of interaction where the user interacts with the virtual data using direct finger manipulations on and around the enclosure surrounding the displayed 3D volumetric image.

  10. Refreshable Braille Displays Using EAP Actuators

    Science.gov (United States)

    Bar-Cohen, Yoseph

    2010-01-01

    Refreshable Braille can help visually impaired persons benefit from the growing advances in computer technology. The development of such displays in a full screen form is a great challenge due to the need to pack many actuators in small area without interferences. In recent years, various displays using actuators such as piezoelectric stacks have become available in commercial form but most of them are limited to one line Braille code. Researchers in the field of electroactive polymers (EAP) investigated methods of using these materials to form full screen displays. This manuscript reviews the state of the art of producing refreshable Braille displays using EAP-based actuators..

  11. PENGARUH DISPLAY PRODUK PADA KEPUTUSAN PEMBELIAN KONSUMEN

    Directory of Open Access Journals (Sweden)

    Ina Melati

    2012-11-01

    Full Text Available Most of ritel outlet recently using product display as a one of their best marketing strategy, the reason is quiet easy to be understood, since consumers are too easy to be teased by those kind of beautiful product display that is being displayed by the retail outlet. The good retail outlets are trying their best to design and make the very good product display, so they can attract more consumers and make them not thinking twice to visit their store and purchase lots of thing. Clearly seeing that an attractive product design is able to influence a consumer to make a buying decision. 

  12. Human Factors Military Lexicon: Auditory Displays

    National Research Council Canada - National Science Library

    Letowski, Tomasz

    2001-01-01

    .... In addition to definitions specific to auditory displays, speech communication, and audio technology, the lexicon includes several terms unique to military operational environments and human factors...

  13. Digital image display system for emergency room

    International Nuclear Information System (INIS)

    Murry, R.C.; Lane, T.J.; Miax, L.S.

    1989-01-01

    This paper reports on a digital image display system for the emergency room (ER) in a major trauma hospital. Its objective is to reduce radiographic image delivery time to a busy ER while simultaneously providing a multimodality capability. Image storage, retrieval, and display will also be facilitated with this system. The system's backbone is a token-ring network of RISC and personal computers. The display terminals are higher- function RISC computers with 1,024 2 color or gray-scale monitors. The PCs serve as administrative terminals. Nuclear medicine, CT, MR, and digitized film images are transferred to the image display system

  14. Spatiotemporal multiple coherence resonances and calcium waves in a coupled hepatocyte system

    International Nuclear Information System (INIS)

    Bao-Hua, Wang; Qi-Shao, Lu; Shu-Juan, Lü; Xiu-Feng, Lang

    2009-01-01

    Spatiotemporal multiple coherence resonances for calcium activities induced by weak Gaussian white noise in coupled hepatocytes are studied. It is shown that bi-resonances in hepatocytes are induced by the interplay and competition between noise and coupling of cells, in other words, the cell in network can be excited either by noise or by its neighbour via gap junction which can transfer calcium ions between cells. Furthermore, the intercellular annular calcium waves induced by noise are observed, in which the wave length decreases with noise intensity augmenting but increases monotonically with coupling strength increasing. And for a fixed noise level, there is an optimal coupling strength that makes the coherence resonance reach maximum. (general)

  15. Utilization of supplemental methionine sources by primary cultures of chick hepatocytes

    International Nuclear Information System (INIS)

    Dibner, J.J.

    1983-01-01

    Utilization of 2-hydroxy-4-(methylthio) butanoic acid (HMB) as a substrate for protein synthesis was studied by using primary cultures of chick liver cells. Cultures were prepared by enzymatic dissociation of livers from week old Hubbard broiler chicks and were maintained for 4 days under nonproliferative conditions. Hepatocyte differentiation was verified by using dexamethasone induction of tyrosine aminotransferase activity. Conversion of [14C]HMB to L-methionine was shown by chromatographic analysis of hepatocyte protein hydrolysate and incorporation into protein was proven by cycloheximide inhibition of synthesis. When incorporation of HMB was compared to that of DL-methionine (DLM) equimolar quantities of the two sources were found in liver cell protein. These results support, at a cellular level, the conclusion that HMB and DLM are biochemically equivalent sources of methionine for protein synthesis

  16. Preparation of Degradable Biological Carrier With LCC and its Application in Culture of Hepatocytes

    Science.gov (United States)

    Zhao, H. K.; Chen, X. K.; Wu, H. F.; Li, J. L.; Xie, Y. M.

    2018-05-01

    The purpose of this article is to extract lignin-carbohydrate complexes (LCC) with poplar as raw material, which was used to prepare bio-carrier by freeze-drying method. The chemical properties and morphological of LCC porous biological carriers were analyzed by GPC, FT-IR, scanning electron microscopy (SEM) and optical microscopy. The FT-IR spectrum results indicated that LCC which are composed of lignin and polysaccharide, with a typical LCC structure. Galactose have a specific ability to recognize liver cells owing to the presence of receptors on hepatocytes. Cell counting results showed that the cells increases fastest while the proliferation rate of the liver cell in LCC is obviously higher than that of control group. These results indicated that poplar LCC is very biocompatible, in which it might be a great potential biological carrier material for human hepatocyte culture.

  17. Liver system. V. Activation-extinction line of cyclic hepatocyte activities.

    Science.gov (United States)

    Dioguardi, N; Brambilla, F; Dell'Oca, M; Arosio, E; Parmeggiani, L

    1991-01-01

    The excitation-extintion line of hepatocytes from an inert state towards the stabilization of a given activity is described. Within the cell, the switching on of any given activity is a competitive process among different activities. The process is driven by the influence field created in the environment of the Rappaport acinus by sinusoidal blood which changes its characteristics during its passage from the portal zone to the central vein. Every step of the excitation-extintion pathway follows the so-called law of autoisodiasostasis (AIS), i.e. it is characterized by an oscillatory motion between restoring (homopoiesis or HP) and working (homeorhesis or HR) states. Since the cyclical bistable equilibrium of AIS characterizes all conditions of hepatocyte activities, the AIS cycle can be defined a limit cycle.

  18. Hanging Drop, A Best Three-Dimensional (3D) Culture Method for Primary Buffalo and Sheep Hepatocytes.

    Science.gov (United States)

    Shri, Meena; Agrawal, Himanshu; Rani, Payal; Singh, Dheer; Onteru, Suneel Kumar

    2017-04-26

    Livestock, having close resemblance to humans, could be a better source of primary hepatocytes than rodents. Herein, we successfully developed three-dimensional (3D) culturing system for primary sheep and buffalo hepatocytes. The 3D-structures of sheep hepatocytes were formed on the fifth-day and maintained until the tenth-day on polyHEMA-coated plates and in hanging drops with William's E media (HDW). Between the cultured and fresh cells, we observed a similar expression of GAPDH, HNF4α, ALB, CYP1A1, CK8 and CK18. Interestingly, a statistically significant increase was noted in the TAT, CPS, AFP, AAT, GSP and PCNA expression. In buffalo hepatocytes culture, 3D-like structures were formed on the third-day and maintained until the sixth-day on polyHEMA and HDW. The expression of HNF4α, GSP, CPS, AFP, AAT, PCNA and CK18 was similar between cultured and fresh cells. Further, a statistically significant increase in the TAT and CK8 expression, and a decrease in the GAPDH, CYP1A1 and ALB expression were noted. Among the culture systems, HDW maintained the liver transcript markers more or less similar to the fresh hepatocytes of the sheep and buffalo for ten and six days, respectively. Taken together, hanging drop is an efficient method for 3D culturing of primary sheep and buffalo hepatocytes.

  19. Endothelial cell-derived matrix promotes the metabolic functional maturation of hepatocyte via integrin-Src signalling.

    Science.gov (United States)

    Guo, Xinyue; Li, Weihong; Ma, Minghui; Lu, Xin; Zhang, Haiyan

    2017-11-01

    The extracellular matrix (ECM) microenvironment is involved in the regulation of hepatocyte phenotype and function. Recently, the cell-derived extracellular matrix has been proposed to represent the bioactive and biocompatible materials of the native ECM. Here, we show that the endothelial cell-derived matrix (EC matrix) promotes the metabolic maturation of human adipose stem cell-derived hepatocyte-like cells (hASC-HLCs) through the activation of the transcription factor forkhead box protein A2 (FOXA2) and the nuclear receptors hepatocyte nuclear factor 4 alpha (HNF4α) and pregnane X receptor (PXR). Reducing the fibronectin content in the EC matrix or silencing the expression of α5 integrin in the hASC-HLCs inhibited the effect of the EC matrix on Src phosphorylation and hepatocyte maturation. The inhibition of Src phosphorylation using the inhibitor PP2 or silencing the expression of Src in hASC-HLCs also attenuated the up-regulation of the metabolic function of hASC-HLCs in a nuclear receptor-dependent manner. These data elucidate integrin-Src signalling linking the extrinsic EC matrix signals and metabolic functional maturation of hepatocyte. This study provides a model for studying the interaction between hepatocytes and non-parenchymal cell-derived matrix. © 2017 The Authors. Journal of Cellular and Molecular Medicine published by John Wiley & Sons Ltd and Foundation for Cellular and Molecular Medicine.

  20. Enhancement of the predicted drug hepatotoxicity in gel entrapped hepatocytes within polysulfone-g-poly (ethylene glycol) modified hollow fiber

    International Nuclear Information System (INIS)

    Shen Chong; Zhang Guoliang; Meng Qin

    2010-01-01

    Collagen gel-based 3D cultures of hepatocytes have been proposed for evaluation of drug hepatotoxicity because of their more reliability than traditional monolayer culture. The collagen gel entrapment of hepatocytes in hollow fibers has been proven to well reflect the drug hepatotoxicity in vivo but was limited by adsorption of hydrophobic drugs onto hollow fibers. This study aimed to investigate the impact of hollow fibers on hepatocyte performance and drug hepatotoxicity. Polysulfone-g-poly (ethylene glycol) (PSf-g-PEG) hollow fiber was fabricated and applied for the first time to suppress the drug adsorption. Then, the impact of hollow fibers was evaluated by detecting the hepatotoxicity of eight selected drugs to gel entrapped hepatocytes within PSf and PSf-g-PEG hollow fibers, or without hollow fibers. The hepatocytes in PSf-g-PEG hollow fiber showed the highest sensitivity to drug hepatotoxicity, while those in PSf hollow fiber and cylindrical gel without hollow fiber underestimated the hepatotoxicity due to either drug adsorption or low hepatic functions. Therefore, the 3D culture of gel entrapped hepatocytes within PSf-g-PEG hollow fiber would be a promising tool for investigation of drug hepatotoxicity in vitro.

  1. Effects of human pharmaceuticals on cytotoxicity, EROD activity and ROS production in fish hepatocytes

    International Nuclear Information System (INIS)

    Laville, N.; Aiet-Aiessa, S.; Gomez, E.; Casellas, C.; Porcher, J.M.

    2004-01-01

    Pharmaceuticals are found in the aquatic environment but their potential effects on non-target species like fish remain unknown. This in vitro study is a first approach in the toxicity assessment of human drugs on fish. Nine pharmaceuticals were tested on two fish hepatocyte models: primary cultures of rainbow trout hepatocytes (PRTH) and PLHC-1 fish cell line. Cell viability, interaction with cytochrome P450 1A (CYP1A) enzyme and oxidative stress were assessed by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrasodium bromide tetrazolium (MTT), 7-ethoxyresorufin-o-deethylase (EROD) and dichlorofluorescein (DCFH-DA) assays, respectively. The tested drugs were clofibrate (CF), fenofibrate (FF), carbamazepine (CBZ), fluoxetine (FX), diclofenac (DiCF), propranolol (POH), sulfamethoxazole (SFX), amoxicillin (AMX) and gadolinium chloride (GdCl 3 ). All substances were cytotoxic, except AMX at concentration up to 500 μM. The calculated MTT EC 50 values ranged from 2 μM (CF) to 651 μM (CBZ) in PLHC-1, and from 53 μM (FF) to 962 μM (GdCl 3 ) in PRTH. CF, FF, and FX were the most cytotoxic drugs and induced oxidative stress before being cytotoxic. Compared to hepatocytes from human and dog, fish hepatocytes seemed to be more susceptible to the peroxisome proliferators (PPs) CF and FF. In PLHC-1 cells none of the tested drugs induced the EROD activity whereas POH appeared as a weak EROD inducer in PRTH. Moreover, in PRTH, SFX, DiCF, CBZ and to a lesser extend, FF and CF inhibited the basal EROD activity at clearly sublethal concentrations which may be of concern at the biological and chemical levels in a multipollution context

  2. Survival of parenchymal hepatocytes exposed to 14.3-MeV neutrons

    International Nuclear Information System (INIS)

    Jirtle, R.L.; Gould, M.N.; DeLuca, P.M. Jr.; Pearson, D.W.

    1982-01-01

    This report presents the results of the measurement of a dose survival curve and RBE values for rat hepatic cells irradiated in vivo with 14.3 MeV neutrons. The purpose was to determine the RBE for neutrons as a function of dose, and whether hepatocytes exposed to neutrons are as efficient at repairing potentially lethal damage as they are after exposure to low LET radiation

  3. CXC chemokines function as a rheostat for hepatocyte proliferation and liver regeneration.

    Directory of Open Access Journals (Sweden)

    Gregory C Wilson

    Full Text Available Our previous in vitro studies have demonstrated dose-dependent effects of CXCR2 ligands on hepatocyte cell death and proliferation. In the current study, we sought to determine if CXCR2 ligand concentration is responsible for the divergent effects of these mediators on liver regeneration after ischemia/reperfusion injury and partial hepatectomy.Murine models of partial ischemia/reperfusion injury and hepatectomy were used to study the effect of CXCR2 ligands on liver regeneration.We found that hepatic expression of the CXCR2 ligands, macrophage inflammatory protein-2 (MIP-2 and keratinocyte-derived chemokine (KC, was significantly increased after both I/R injury and partial hepatectomy. However, expression of these ligands after I/R injury was 30-100-fold greater than after hepatectomy. Interestingly, the same pattern of expression was found in ischemic versus non-ischemic liver lobes following I/R injury with expression significantly greater in the ischemic liver lobes. In both systems, lower ligand expression was associated with increased hepatocyte proliferation and liver regeneration in a CXCR2-dependent fashion. To confirm that these effects were related to ligand concentration, we administered exogenous MIP-2 and KC to mice undergoing partial hepatectomy. Mice received a "high" dose that replicated serum levels found after I/R injury and a "low" dose that was similar to that found after hepatectomy. Mice receiving the "high" dose had reduced levels of hepatocyte proliferation and regeneration whereas the "low" dose promoted hepatocyte proliferation and regeneration.Together, these data demonstrate that concentrations of CXC chemokines regulate the hepatic proliferative response and subsequent liver regeneration.

  4. Oxygen dependency of epidermal growth factor receptor binding and DNA synthesis of rat hepatocytes

    International Nuclear Information System (INIS)

    Hirose, Tetsuro; Terajima, Hiroaki; Yamauchi, Akira

    1997-01-01

    Background/Aims: Changes in oxygen availability modulate replicative responses in several cell types, but the effects on hepatocyte replication remain unclear. We have studied the effects of transient nonlethal hypoxia on epidermal growth factor receptor binding and epidermal growth factor-induced DNA synthesis of rat hepatocytes. Methods: Lactate dehydrogenase activity in culture supernatant, intracellular adenosine triphosphate content, 125 I-epidermal growth factor specific binding, epidermal growth factor receptor protein expression, and 3 H-thymidine incorporation were compared between hepatocytes cultured in hypoxia and normoxia. Results: Hypoxia up to 3 h caused no significant increase in lactate dehydrogenase activity in the culture supernatant, while intracellular adenosine triphosphate content decreased time-dependently and was restored to normoxic levels by reoxygenation (nonlethal hypoxia). Concomitantly, 125 I-epidermal growth factor specific binding to hepatocytes decreased time-dependently (to 54.1% of normoxia) and was restored to control levels by reoxygenation, although 125 I-insulin specific binding was not affected. The decrease in 125 I-epidermal growth factor specific binding was explained by the decrease in the number or available epidermal growth factor receptors (21.37±3.08 to 12.16±1.42 fmol/10 5 cells), while the dissociation constant of the receptor was not affected. The change in the number of available receptors was not considered to be due to receptor degradation-resynthesis, since immuno-detection of the epidermal growth factor receptor revealed that the receptor protein expression did not change during hypoxia and reoxygenation, and since neither actinomycin D nor cycloheximide affected the recovery of 125 I-epidermal growth factor binding by reoxygenation. Inhibition of epidermal growth factor-induced DNA synthesis after hypoxia (to 75.4% of normoxia by 3 h hypoxia) paralleled the decrease in 125 I-epidermal growth factor binding

  5. Hepatitis B virus evasion from cGAS sensing in human hepatocytes.

    Science.gov (United States)

    Verrier, Eloi R; Yim, Seung-Ae; Heydmann, Laura; El Saghire, Houssein; Bach, Charlotte; Turon-Lagot, Vincent; Mailly, Laurent; Durand, Sarah C; Lucifora, Julie; Durantel, David; Pessaux, Patrick; Manel, Nicolas; Hirsch, Ivan; Zeisel, Mirjam B; Pochet, Nathalie; Schuster, Catherine; Baumert, Thomas F

    2018-04-20

    Chronic hepatitis B virus (HBV) infection is a major cause of chronic liver disease and cancer worldwide. The mechanisms of viral genome sensing and the evasion of innate immune responses by HBV infection are still poorly understood. Recently, the cyclic GMP-AMP synthase (cGAS) was identified as a DNA sensor. In this study, we aimed to investigate the functional role of cGAS in sensing of HBV infection and elucidate the mechanisms of viral evasion. We performed functional studies including loss- and gain-of-function experiments combined with cGAS effector gene expression profiling in an infectious cell culture model, primary human hepatocytes and HBV-infected human liver chimeric mice. Here we show that cGAS is expressed in the human liver, primary human hepatocytes and human liver chimeric mice. While naked relaxed-circular HBV DNA is sensed in a cGAS-dependent manner in hepatoma cell lines and primary human hepatocytes, host cell recognition of viral nucleic acids is abolished during HBV infection, suggesting escape from sensing, likely during packaging of the genome into the viral capsid. While the hepatocyte cGAS pathway is functionally active, as shown by reduction of viral cccDNA levels in gain-of-function studies, HBV infection suppressed cGAS expression and function in cell culture models and humanized mice. HBV exploits multiple strategies to evade sensing and antiviral activity of cGAS and its effector pathways. This article is protected by copyright. All rights reserved. © 2018 by the American Association for the Study of Liver Diseases.

  6. Mechanism of free radical generation in platelets and primary hepatocytes: A novel electron spin resonance study.

    Science.gov (United States)

    Wang, Chiun-Lang; Yang, Po-Sheng; Tsao, Jeng-Ting; Jayakumar, Thanasekaran; Wang, Meng-Jiy; Sheu, Joen-Rong; Chou, Duen-Suey

    2018-01-01

    Oxygen free radicals have been implicated in the pathogenesis of toxic liver injury and are thought to be involved in cardiac dysfunction in the cirrhotic heart. Therefore, direct evidence for the electron spin resonance (ESR) detection of how D‑galactosamine (GalN), an established experimental hepatotoxic substance, induced free radicals formation in platelets and primary hepatocytes is presented in the present study. ESR results demonstrated that GalN induced hydroxyl radicals (OH•) in a resting human platelet suspension; however, radicals were not produced in a cell free Fenton reaction system. The GalN‑induced OH• formation was significantly inhibited by the cyclooxygenase (COX) inhibitor indomethasin, though it was not affected by the lipoxygenase (LOX) or cytochrome P450 inhibitors, AA861 and 1‑aminobenzotriazole (ABT), in platelets. In addition, the present study demonstrated that baicalein induced semiquinone free radicals in platelets, which were significantly reduced by the COX inhibitor without affecting the formed OH•. In the mouse primary hepatocytes, the formation of arachidonic acid (AA) induced carbon‑centered radicals that were concentration dependently enhanced by GalN. These radicals were inhibited by AA861, though not affected by indomethasin or ABT. In addition, GalN did not induce platelet aggregation prior to or following collagen pretreatment in human platelets. The results of the present study indicated that GalN and baicalein may induce OH• by COX and LOX in human platelets. GalN also potentiated AA induced carbon‑centered radicals in hepatocytes via cytochrome P450. The present study presented the role of free radicals in the pathophysiological association between platelets and hepatocytes.

  7. Activation-dependent mitochondrial translocation of Foxp3 in human hepatocytes

    International Nuclear Information System (INIS)

    Rojas, Joselyn; Teran-Angel, Guillermo; Barbosa, Luisa; Peterson, Darrell L.; Berrueta, Lisbeth; Salmen, Siham

    2016-01-01

    Foxp3 is considered to be the master regulator for the development and function of regulatory T cells (Treg). Recently Foxp3, has been detected in extra lymphoid tissue, and in hepatocytes and has been associated with hepatocellular carcinoma (HCC), although its role has not been defined. Since it is expected that there is a relationship between protein localization, activity and cellular function, the aim of this study was to explore the subcellular localization of Foxp3 in resting and stimulated human hepatocytes. Foxp3 expression was measured by flow cytometry, subcellular fractioning, and immunofluorescence, and this data was used to track the shuttling of Foxp3 in different subcellular compartments in hepatocytes (HepG2 cell line), stimulated by using the PKC activators (PMA), core and preS1/2 antigen from hepatitis B virus (HBV). Our data shows that besides the nuclear location, mitochondrial translocation was detected after stimulation with PMA and at to a lesser extent, with preS1/2. In addition, Foxp3 is localizes at outer mitochondrial membrane. These results suggest a non-canonical role of Foxp3 in the mitochondrial compartment in human hepatocytes, and opens a new field about their role in liver damages during HBV infection. - Highlights: • The expression and subcellular distribution of Foxp3, is modulated by PMA and preS1/2. • PMA and preS1/2 increase Foxp3 expression on HepG2. • PMA and preS1/2 induce foxp3 enrichment at mitochondrial, microsomal and nuclear compartments. • Results suggest a non-canonical function of Foxp3 or a mitochondrial transcriptional activity.

  8. Polyploidization of rat hepatocytes due to cell fusion under the effect of radiation of different let

    International Nuclear Information System (INIS)

    Gil'yano, N.Ya.; Malinovskij, O.V.; Khair, M.B.; Baldychev, A.S.; Smolin, V.A.

    1988-01-01

    The method of flow cytometry was used to study polyploidization of hepatocytes following X-, γ-, and neutron-irradiation. Ionizing radiation was shown to induce cell polyploidization by two different ways: (1) cells and nuclei fusion, and (2) restriction of mitosis after DNA replication. RBE of 14 MeV neutrons with respect to fusion was about 5x10 3 . With neutron irradiation, the densitivity of cells by fusion was not lower than that by chromosome mutations

  9. Polyploidization of rat hepatocytes due to cell fusion under the effect of radiation of different LET

    International Nuclear Information System (INIS)

    Khair, M.; Gil'yano, N.Ya.; Malinovskij, O.V.; Smolin, V.A.

    1991-01-01

    The method of flow cytometry was used to study polyploidization of hepatocytes following X-, γ-, and neutron-irradiation. Ionizing radiation was shown to induce cell polyploidization by two different ways: (1) cells and nuclei fusion, and (2) restriction of mitosis after DNA replication. RBE of 14 MeV neutrons with respect to fusion was about 5x10 3 . With neutron irradiation, the sensitivity of cells by fusion was not lower than that by chromosome mutations. (author). 6 refs., 6 figs

  10. Single-cell analysis of ploidy and centrosomes underscores the peculiarity of normal hepatocytes.

    Directory of Open Access Journals (Sweden)

    Francesca Faggioli

    Full Text Available Polyploidization is the most well recognized feature of the liver. Yet, a quantitative and behavioral analysis of centrosomes and DNA content in normal hepatocytes has been limited by the technical challenges of methods available. By using a novel approach employing FISH for chromosomes 18, X and Y we provide, for the first time, a detailed analysis of DNA copies during physiological development in the liver at single cell level. We demonstrate that aneuploidy and unbalanced DNA content in binucleated hepatocytes are common features in normal adult liver. Despite the common belief that hepatocytes contain 1, 2 or no more than 4 centrosomes, our double staining for centrosome associated proteins reveals extranumerary centrosomes in a high percentage of cells as early as 15 days of age. We show that in murine liver the period between 15 days and 1.5 months marks the transition from a prevalence of mononucleated cells to up to 75% of binucleated cells. Our data demonstrate that this timing correlates with a switch in centrosomes number. At 15 days the expected 1 or 2 centrosomes converge with several hepatocytes that contain 3 centrosomes; at 1.5 months the percentage of cells with 3 centrosomes decreases concomitantly with the increase of cells with more than 4 centrosomes. Our analysis shows that the extranumerary centrosomes emerge in concomitance with the process of binucleation and polyploidization and maintain α-tubulin nucleation activity. Finally, by integrating interphase FISH and immunofluorescent approaches, we detected an imbalance between centrosome number and DNA content in liver cells that deviates from the equilibrium expected in normal cells. We speculate that these unique features are relevant to the peculiar biological function of liver cells which are continuously challenged by stress, a condition that could predispose to genomic instability.

  11. Polyploidization delay in rat hepatocytes under liver growth inhibition by hypokinesia

    Science.gov (United States)

    Faktor, V. M.; Malyutin, V. F.; Li, S. Y.; Brodskiy, V. Y.

    1981-01-01

    A study of young rats, weighing 55 to 59 g, after being for 10 days in conditions of limited mobility, shows a retardation of body growth as well as that of liver growth. The decrease in the rate of growth is accompanied by a reduction of cell proliferation and by delay polyploidization of hepatocytes in the liver of experimental rats. The materials, methods, and results of research are discussed.

  12. Hepatic iron overload is associated with hepatocyte apoptosis during Clonorchis sinensis infection.

    Science.gov (United States)

    Han, Su; Tang, Qiaoran; Chen, Rui; Li, Yihong; Shu, Jing; Zhang, Xiaoli

    2017-08-01

    Hepatic iron overload has been implicated in many liver diseases; however, whether it is involved in clonorchiasis remains unknown. The purpose of this study is to investigate whether Clonorchis sinensis (C. sinensis) infection causes hepatic iron overload, analyze the relationship between the iron overload and associated cell apoptosis, so as to determine the role of excess iron plays in C. sinensis-induced liver injury. The Perls' Prussian staining and atomic absorption spectrometry methods were used to investigate the iron overload in hepatic sections of wistar rats and patients infected with C. sinensis. The hepatic apoptosis was detected by transferase uridyl nick end labeling (TUNEL) methods. Spearman analysis was used for determining the correlation of the histological hepatic iron index and the apoptotic index. Blue iron particles were deposited mainly in the hepatocytes, Kupffer cells and endothelial cells, around the liver portal and central vein area of both patients and rats. The total iron score was found to be higher in the infected groups than the respective control from 8 weeks. The hepatic iron concentration was also significantly higher in treatment groups than in control rats from 8 weeks. The hepatocyte apoptosis was found to be significantly higher in the portal area of the liver tissue and around the central vein. However, spearman's rank correlation coefficient revealed that there was a mildly negative correlation between the iron index and hepatocyte apoptosis. This present study confirmed that hepatic iron overload was found during C. sinensis infection. This suggests that iron overload may be associated with hepatocyte apoptosis and involved in liver injury during C. sinensis infection. Further studies are needed to investigate the molecular mechanism involved here.

  13. Augmentation of DHCR24 expression by hepatitis C virus infection facilitates viral replication in hepatocytes.

    Science.gov (United States)

    Takano, Takashi; Tsukiyama-Kohara, Kyoko; Hayashi, Masahiro; Hirata, Yuichi; Satoh, Masaaki; Tokunaga, Yuko; Tateno, Chise; Hayashi, Yukiko; Hishima, Tsunekazu; Funata, Nobuaki; Sudoh, Masayuki; Kohara, Michinori

    2011-09-01

    We characterized the role of 24-dehydrocholesterol reductase (DHCR24) in hepatitis C virus infection (HCV). DHCR24 is a cholesterol biosynthetic enzyme and cholesterol is a major component of lipid rafts, which is reported to play an important role in HCV replication. Therefore, we examined the potential of DHCR24 as a target for novel HCV therapeutic agents. We examined DHCR24 expression in human hepatocytes in both the livers of HCV-infected patients and those of chimeric mice with human hepatocytes. We targeted DHCR24 with siRNA and U18666A which is an inhibitor of both DHCR24 and cholesterol synthesis. We measured the level of HCV replication in these HCV replicon cell lines and HCV infected cells. U18666A was administrated into chimeric mice with humanized liver, and anti-viral effects were assessed. Expression of DHCR24 was induced by HCV infection in human hepatocytes in vitro, and in human hepatocytes of chimeric mouse liver. Silencing of DHCR24 by siRNA decreased HCV replication in replicon cell lines and HCV JFH-1 strain-infected cells. Treatment with U18666A suppressed HCV replication in the replicon cell lines. Moreover, to evaluate the anti-viral effect of U18666A in vivo, we administrated U18666A with or without pegylated interferon to chimeric mice and observed an inhibitory effect of U18666A on HCV infection and a synergistic effect with interferon. DHCR24 is an essential host factor which augmented its expression by HCV infection, and plays a significant role in HCV replication. DHCR24 may serve as a novel anti-HCV drug target. Copyright © 2010 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

  14. Activation-dependent mitochondrial translocation of Foxp3 in human hepatocytes

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, Joselyn; Teran-Angel, Guillermo; Barbosa, Luisa [Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of); Peterson, Darrell L. [Department of Biochemistry and Molecular Biology, Virginia Commonwealth University, Richmond, VA (United States); Berrueta, Lisbeth, E-mail: lberruet@ula.ve [Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of); Division of Preventive Medicine, Brigham and Women' s Hospital, Harvard Medical School, Boston, MA (United States); Salmen, Siham, E-mail: sihamsa@ula.ve [Instituto de Inmunología Clínica, Facultad de Medicina, Universidad de Los Andes, Merida (Venezuela, Bolivarian Republic of)

    2016-05-01

    Foxp3 is considered to be the master regulator for the development and function of regulatory T cells (Treg). Recently Foxp3, has been detected in extra lymphoid tissue, and in hepatocytes and has been associated with hepatocellular carcinoma (HCC), although its role has not been defined. Since it is expected that there is a relationship between protein localization, activity and cellular function, the aim of this study was to explore the subcellular localization of Foxp3 in resting and stimulated human hepatocytes. Foxp3 expression was measured by flow cytometry, subcellular fractioning, and immunofluorescence, and this data was used to track the shuttling of Foxp3 in different subcellular compartments in hepatocytes (HepG2 cell line), stimulated by using the PKC activators (PMA), core and preS1/2 antigen from hepatitis B virus (HBV). Our data shows that besides the nuclear location, mitochondrial translocation was detected after stimulation with PMA and at to a lesser extent, with preS1/2. In addition, Foxp3 is localizes at outer mitochondrial membrane. These results suggest a non-canonical role of Foxp3 in the mitochondrial compartment in human hepatocytes, and opens a new field about their role in liver damages during HBV infection. - Highlights: • The expression and subcellular distribution of Foxp3, is modulated by PMA and preS1/2. • PMA and preS1/2 increase Foxp3 expression on HepG2. • PMA and preS1/2 induce foxp3 enrichment at mitochondrial, microsomal and nuclear compartments. • Results suggest a non-canonical function of Foxp3 or a mitochondrial transcriptional activity.

  15. The influence of hydrocortisone on postirradiation disturbances of potassium homeostasis in exposed rat hepatocytes

    International Nuclear Information System (INIS)

    Mashkova, N.Yu.; Borovikova, G.V.; Dokshina, G.A.

    1988-01-01

    The influence of hydrocortisone and radiation on potassium homeostasis in isolated hepatocytes (in vivo experiments) and perfusing liver of mongrel rats has been investigated. The effects of hydrocortisone and radiation (7 Gy) on redistribution of intracellular potassium are shown to be similar with respect to their depth and direction. However with the hormone and ionizing radiation delivered simultaneously no additivity of the effects is registered

  16. Glucose metabolism and recycling by hepatocytes of OB/OB and ob/ob mice

    International Nuclear Information System (INIS)

    Lahtela, J.T.; Wals, P.A.; Katz, J.

    1990-01-01

    Hepatocytes were prepared from livers of ob/ob (obese diabetic) mice and their lean (OB/OB) siblings that had been fasted for 24 h. The hepatocytes were incubated with [U-14C, 2-3H]-, [U-14C, 3-3H]-, and [U-14C, 6-3H]glucose at concentrations from 20 to 120 mM. 14C was recovered mainly in CO2, glycogen, and lactate. Tritium was recovered in water and glycogen. The yield in labeled products from [2-3H]glucose ranged from two to three times that from [U-14C]glucose. The yields from [3-3H]- and [6-3H]glucose were similar, and 1.3-1.7 times that from [U-14C]glucose. At 40 mM, total utilization of glucose by obese mice was about twice that for lean mice, but there was little difference at 120 mM. The rate of recycling between glucose and glucose 6-phosphate was calculated. An equation to calculate the rate of recycling of glucose from the 2-3H/U-14C ratio in glycogen is derived in the APPENDIX. Our results show that (1) the utilization of glucose by hepatocytes from obese diabetic mice exceeds that of their lean controls, (2) the rate of glucose phosphorylation in both groups greatly exceeds glucose uptake and the rate of glycogen synthesis, (3) glucose phosphorylation represents a difference between a high glucokinase rate and hydrolysis of glucose 6-phosphate, and (4) recycling of glucose carbon between glucose 6-phosphate and pyruvate occurs within mouse hepatocytes

  17. The extracellular redox state modulates mitochondrial function, gluconeogenesis, and glycogen synthesis in murine hepatocytes.

    Science.gov (United States)

    Nocito, Laura; Kleckner, Amber S; Yoo, Elsia J; Jones Iv, Albert R; Liesa, Marc; Corkey, Barbara E

    2015-01-01

    Circulating redox state changes, determined by the ratio of reduced/oxidized pairs of different metabolites, have been associated with metabolic diseases. However, the pathogenic contribution of these changes and whether they modulate normal tissue function is unclear. As alterations in hepatic gluconeogenesis and glycogen metabolism are hallmarks that characterize insulin resistance and type 2 diabetes, we tested whether imposed changes in the extracellular redox state could modulate these processes. Thus, primary hepatocytes were treated with different ratios of the following physiological extracellular redox couples: β-hydroxybutyrate (βOHB)/acetoacetate (Acoc), reduced glutathione (GSH)/oxidized glutathione (GSSG), and cysteine/cystine. Exposure to a more oxidized ratio via extracellular βOHB/Acoc, GSH/GSSG, and cysteine/cystine in hepatocytes from fed mice increased intracellular hydrogen peroxide without causing oxidative damage. On the other hand, addition of more reduced ratios of extracellular βOHB/Acoc led to increased NAD(P)H and maximal mitochondrial respiratory capacity in hepatocytes. Greater βOHB/Acoc ratios were also associated with decreased β-oxidation, as expected with enhanced lipogenesis. In hepatocytes from fasted mice, a more extracellular reduced state of βOHB/Acoc led to increased alanine-stimulated gluconeogenesis and enhanced glycogen synthesis capacity from added glucose. Thus, we demonstrated for the first time that the extracellular redox state regulates the major metabolic functions of the liver and involves changes in intracellular NADH, hydrogen peroxide, and mitochondrial respiration. Because redox state in the blood can be communicated to all metabolically sensitive tissues, this work confirms the hypothesis that circulating redox state may be an important regulator of whole body metabolism and contribute to alterations associated with metabolic diseases.

  18. The extracellular redox state modulates mitochondrial function, gluconeogenesis, and glycogen synthesis in murine hepatocytes.

    Directory of Open Access Journals (Sweden)

    Laura Nocito

    Full Text Available Circulating redox state changes, determined by the ratio of reduced/oxidized pairs of different metabolites, have been associated with metabolic diseases. However, the pathogenic contribution of these changes and whether they modulate normal tissue function is unclear. As alterations in hepatic gluconeogenesis and glycogen metabolism are hallmarks that characterize insulin resistance and type 2 diabetes, we tested whether imposed changes in the extracellular redox state could modulate these processes. Thus, primary hepatocytes were treated with different ratios of the following physiological extracellular redox couples: β-hydroxybutyrate (βOHB/acetoacetate (Acoc, reduced glutathione (GSH/oxidized glutathione (GSSG, and cysteine/cystine. Exposure to a more oxidized ratio via extracellular βOHB/Acoc, GSH/GSSG, and cysteine/cystine in hepatocytes from fed mice increased intracellular hydrogen peroxide without causing oxidative damage. On the other hand, addition of more reduced ratios of extracellular βOHB/Acoc led to increased NAD(PH and maximal mitochondrial respiratory capacity in hepatocytes. Greater βOHB/Acoc ratios were also associated with decreased β-oxidation, as expected with enhanced lipogenesis. In hepatocytes from fasted mice, a more extracellular reduced state of βOHB/Acoc led to increased alanine-stimulated gluconeogenesis and enhanced glycogen synthesis capacity from added glucose. Thus, we demonstrated for the first time that the extracellular redox state regulates the major metabolic functions of the liver and involves changes in intracellular NADH, hydrogen peroxide, and mitochondrial respiration. Because redox state in the blood can be communicated to all metabolically sensitive tissues, this work confirms the hypothesis that circulating redox state may be an important regulator of whole body metabolism and contribute to alterations associated with metabolic diseases.

  19. Effect of ornithine on ammonia utilization and urea synthesis in isolated hepatocytes from fed rats

    International Nuclear Information System (INIS)

    Garwacki, S.; Wiechetek, M.; Souffrant, W.B.

    1988-01-01

    The effect of ornithine on the ammonia utilization and urea synthesis in hepatocytes isolated from fed male Wistar rats was investigated. On the basis of the 15 N tracer technique, it was found that ornithine stimulated urea synthesis with an increased utilization of the exogenously marked ammonia for urea, but deminished its utilization in other N-metabolic processes. The results also showed that the stimulation of urea synthesis due to ornithine resulted from the utilization of both exogenous and endogenous sources. (author)

  20. Heme oxygenase-1 prevents non-alcoholic steatohepatitis through suppressing hepatocyte apoptosis in mice

    Directory of Open Access Journals (Sweden)

    Fu Na

    2010-10-01

    Full Text Available Abstract Objective Heme oxygenase-1 (HO-1, the rate-limiting enzyme in heme catabolism, has been reported to have potential antioxidant properties. However, the role of HO-1 on hepatocyte apoptosis remains unclear. We aim to elucidate the effects of HO-1 on oxidative stress related hepatocellular apoptosis in nutritional steatohepatitis in mice. Methods C57BL/6J mice were fed with methionine-choline deficient (MCD diet for four weeks to induce hepatic steatohepatitis. HO-1 chemical inducer (hemin, HO-1 chemical inhibitor zinc protoporphyrin IX (ZnPP-IX and/or adenovirus carrying HO-1 gene (Ad-HO-1 were administered to mice, respectively. Hepatocyte apoptosis was evaluated by terminal deoxynucleotidyl transferase dUTP nick-end labeling (TUNEL assay, the mRNA and protein expression of apoptosis related genes were assayed by quantitative real-time PCR and Western blot. Results Hepatocyte signs of oxidative related apoptotic injury were presented in mice fed with MCD diet for 4 weeks. Induction of HO-1 by hemin or Ad-HO-1 significantly attenuated the severity of liver histology, which was associated with decreased hepatic lipid peroxidation content, reduced number of apoptotic cells by TUNEL staining, down-regulated expression of pro-apoptosis related genes including Fas/FasL, Bax, caspase-3 and caspase-9, reduced expression of cytochrome p4502E1 (CYP2E1, inhibited cytochrome c (Cyt-c release, and up-regulated expression of anti-apoptosis gene Bcl-2. Whereas, inhibition of HO-1 by ZnPP-IX caused oxidative stress related hepatic injury, which concomitant with increased number of TUNEL positive cells and up-regulated expression of pro-apoptosis related genes. Conclusions The present study provided evidences for the protective role of HO-1 in preventing nutritional steatohepatitis through suppressing hepatocyte apoptosis in mice.

  1. The absence of 2,3-diphosphoglycerate from myocytes, hepatocytes and adipocytes.

    Science.gov (United States)

    Reddy, W J; Burns, A H

    1976-04-23

    Myocytes, hepatocytes and adipocytes were prepared from heart, liver and epididymal fat pad of the rat. No detectable level of 2,3-diphosphoglycerate was found. Evidence is also presented which indicates the absence from these cells of 2,3-diphosphoglycerate mutase and 2,3-diphosphoglycerate phosphatase. Previous findings by others of the presence of 2,3-diphosphoglycerate and 2,3-diphosphoglycerate mutase probably resulted from erythrocytes sequestered in the tissue.

  2. Inhibition of DNA synthesis by chemical carcinogens in cultures of initiated and normal proliferating rat hepatocytes

    International Nuclear Information System (INIS)

    Novicki, D.L.; Rosenberg, M.R.; Michalopoulos, G.

    1985-01-01

    Rat hepatocytes in primary culture can be stimulated to replicate under the influence of rat serum and sparse plating conditions. Higher replication rates are induced by serum from two-thirds partially hepatectomized rats. The effects of carcinogens and noncarcinogens on the ability of hepatocytes to synthesize DNA were examined by measuring the incorporation of [3H]thymidine by liquid scintillation counting and autoradiography. Hepatocyte DNA synthesis was not decreased by ethanol or dimethyl sulfoxide at concentrations less than 0.5%. No effect was observed when 0.1 mM ketamine, Nembutal, hypoxanthine, sucrose, ascorbic acid, or benzo(e)pyrene was added to cultures of replicating hepatocytes. Estrogen, testosterone, tryptophan, and vitamin E inhibited DNA synthesis by approximately 50% at 0.1 mM, a concentration at which toxicity was noticeable. Several carcinogens requiring metabolic activation as well as the direct-acting carcinogen N-methyl-N'-nitro-N-nitrosoguanidine interfered with DNA synthesis. Aflatoxin B1 inhibited DNA synthesis by 50% (ID50) at concentrations between 1 X 10(-8) and 1 X 10(-7) M. The ID50 for 2-acetylaminofluorene was between 1 X 10(-7) and 1 X 10(-6) M. Benzo(a)pyrene and 3'-methyl-4-dimethylaminoazobenzene inhibited DNA synthesis 50% between 1 X 10(-5) and 1 X 10(-4) M. Diethylnitrosamine and dimethylnitrosamine (ID50 between 1 X 10(-4) and 5 X 10(-4) M) and 1- and 2-naphthylamine (ID50 between 1 X 10(-5) and 5 X 10(-4) M) caused inhibition of DNA synthesis at concentrations which overlapped with concentrations that caused measurable toxicity

  3. Prolyl hydroxylase-1 regulates hepatocyte apoptosis in an NF-κB-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fitzpatrick, Susan F.; Fábián, Zsolt; Schaible, Bettina; Lenihan, Colin R.; Schwarzl, Thomas [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Rodriguez, Javier [Systems Biology Ireland, University College Dublin, Dublin 4 (Ireland); Zheng, Xingnan; Li, Zongwei [Lineberger Comprehensive Cancer Center, University of North Carolina School of Medicine, Chapel Hill, NC (United States); Tambuwala, Murtaza M. [School of Pharmacy and Pharmaceutical Sciences, Ulster University, Coleraine, BT52 1SA, Northern Ireland (United Kingdom); Higgins, Desmond G.; O' Meara, Yvonne [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Slattery, Craig [School of Biomolecular and Biomedical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Manresa, Mario C. [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); Fraisl, Peter; Bruning, Ulrike [Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, University of Leuven, Vesalius Research Center, VIB, B-3000 (Belgium); Baes, Myriam [Laboratory for Cell Metabolism, Department of Pharmaceutical and Pharmacological Sciences, KU Leuven (Belgium); Carmeliet, Peter; Doherty, Glen [Laboratory of Angiogenesis and Vascular Metabolism, Department of Oncology, University of Leuven, Vesalius Research Center, VIB, B-3000 (Belgium); Kriegsheim, Alex von [Systems Biology Ireland, University College Dublin, Dublin 4 (Ireland); Cummins, Eoin P. [School of Medicine and Medical Science, The Conway Institute, University College Dublin, Belfield, Dublin 4 Ireland (Ireland); and others

    2016-06-03

    Hepatocyte death is an important contributing factor in a number of diseases of the liver. PHD1 confers hypoxic sensitivity upon transcription factors including the hypoxia inducible factor (HIF) and nuclear factor-kappaB (NF-κB). Reduced PHD1 activity is linked to decreased apoptosis. Here, we investigated the underlying mechanism(s) in hepatocytes. Basal NF-κB activity was elevated in PHD1{sup −/−} hepatocytes compared to wild type controls. ChIP-seq analysis confirmed enhanced binding of NF-κB to chromatin in regions proximal to the promoters of genes involved in the regulation of apoptosis. Inhibition of NF-κB (but not knock-out of HIF-1 or HIF-2) reversed the anti-apoptotic effects of pharmacologic hydroxylase inhibition. We hypothesize that PHD1 inhibition leads to altered expression of NF-κB-dependent genes resulting in reduced apoptosis. This study provides new information relating to the possible mechanism of therapeutic action of hydroxylase inhibitors that has been reported in pre-clinical models of intestinal and hepatic disease. -- Highlights: •Genetic ablation of PHD1 upregulates NF-kappaB (NF-κB) in hepatocytes. •Activation of NF-κB leads to differential DNA-binding of p50/p65 and results in differential regulation of apoptotic genes. •We identified proline 191 in the beta subunit of the I-kappaB kinase as a target for PHD1-mediated hydroxylation. •Blockade of prolyl-4-hydroxylases has been found cytoprotective in liver cells.

  4. Liver/kidney microsomal antibody type 1 targets CYP2D6 on hepatocyte plasma membrane.

    Science.gov (United States)

    Muratori, L; Parola, M; Ripalti, A; Robino, G; Muratori, P; Bellomo, G; Carini, R; Lenzi, M; Landini, M P; Albano, E; Bianchi, F B

    2000-04-01

    Liver/kidney microsomal antibody type 1 (LKM1) is the marker of type 2 autoimmune hepatitis (AIH) and is detected in up to 6% of patients with hepatitis C virus (HCV) infection. It recognises linear and conformational epitopes of cytochrome P450IID6 (CYP2D6) and may have liver damaging activity, provided that CYP2D6 is accessible to effector mechanisms of autoimmune attack. The presence of LKM1 in the plasma membrane was investigated by indirect immunofluorescence and confocal laser microscopy of isolated rat hepatocytes probed with 10 LKM1 positive sera (five from patients with AIH and five from patients with chronic HCV infection) and a rabbit polyclonal anti-CYP2D6 serum. Serum from both types of patient stained the plasma membrane of non-permeabilised cells, where the fluorescent signal could be visualised as discrete clumps. Conversely, permeabilised hepatocytes showed diffuse submembranous/cytoplasmic staining. Adsorption with recombinant CYP2D6 substantially reduced plasma membrane staining and LKM1 immunoblot reactivity. Plasma membrane staining of LKM1 colocalised with that of anti-CYP2D6. Immunoprecipitation experiments showed that a single 50 kDa protein recognised by anti-CYP2D6 can be isolated from the plasma membrane of intact hepatocytes. AIH and HCV related LKM1 recognise CYP2D6 exposed on the plasma membrane of isolated hepatocytes. This observation supports the notion that anti-CYP2D6 autoreactivity may be involved in the pathogenesis of liver damage.

  5. Carbon Tetrachloride Increases Intracellular Calcium in Rat Liver and Hepatocyte Cultures

    Science.gov (United States)

    1986-05-12

    tible to destruction by CC14 ( Head ~ al., 1981). Thus, the activation of CC14 to a toxic moiety clearly depends upon metabolism by one or more... embryologic development (Wyllie, 1986). In contrast, Toyo-oka et al. (1985) could not establish that phospholipase& or proteases were involved in ischemic...D. M. Bissell, and u. A Meyer. (1977) Drug Metabolism in Adult Rat Hepatocyte& in Primary Monolayer Culture. Gastroenterology 72:1232-1239. Head , B

  6. Effect of display location on control-display stereotype strength for translational and rotational controls with linear displays.

    Science.gov (United States)

    Chan, Alan H S; Hoffmann, Errol R

    2015-01-01

    Experiments were designed to investigate the effects of control type and display location, relative to the operator, on the strength of control/display stereotypes. The Worringham and Beringer Visual Field principle and an extension of this principle for rotary controls (Hoffmann E.R., and Chan A.H.S. 2013). "The Worringham and Beringer 'Visual Field' Principle for Rotary Controls. Ergonomics." 56 (10): 1620-1624) indicated that, for a number of different control types (rotary and lever) on different planes, there should be no significant effect of the display location relative to the seated operator. Past data were surveyed and stereotype strengths listed. Experiments filled gaps where data are not available. Six different control types and seven display locations were used, as in the Frame of Reference Transformation Tool (FORT) model of Wickens et al. (Wickens, C.D., Keller, J.W., and Small, R.L. (2010). "Left. No, Right! Development of the Frame of Reference Transformation Tool (FORT)." Proceedings of the Human Factors and Ergonomics Society 54th Annual Meeting September 2010, 54: 1022-1026). Control/display arrangements with high stereotype strengths were evaluated yielding data for designers of complex control/display arrangements where the control and display are in different planes and for where the operator is moving. It was found possible to predict display/control arrangements with high stereotype strength, based on past data. Practitioner Summary: Controls and displays in complex arrangements need to have high compatibility. These experiments provide arrangements for six different controls (rotary and translational) and seven different display locations relative to the operator.

  7. Effect of guava (Psidium guajava L.) leaf extract on glucose uptake in rat hepatocytes.

    Science.gov (United States)

    Cheng, Fang-Chi; Shen, Szu-Chuan; Wu, James Swi-Bea

    2009-06-01

    People in oriental countries, including Japan and Taiwan, boil guava leaves (Psidium guajava L.) in water and drink the extract as a folk medicine for diabetes. The present study investigated the enhancement of aqueous guava leaf extract on glucose uptake in rat clone 9 hepatocytes and searched for the active compound. The extract was eluted with MeOH-H(2)O solutions through Diaion, Sephadex, and MCI-gel columns to separate into fractions with different polarities. The uptake test of 2-[1-(14)C] deoxy-D-glucose in rat clone 9 hepatocytes was performed to evaluate the hypoglycemic effect of these fractions. The active compound was identified by nuclear magnetic resonance analysis and high-performance liquid chromatography (HPLC). The results revealed that phenolics are the principal component of the extract, that high polarity fractions of the guava leaf extract are enhancers to glucose uptake in rat clone 9 hepatocytes, and that quercetin is the major active compound. We suggest that quercetin in the aqueous extract of guava leaves promotes glucose uptake in liver cells, and contributes to the alleviation of hypoglycemia in diabetes as a consequence.

  8. Arsenite Effects on Mitochondrial Bioenergetics in Human and Mouse Primary Hepatocytes Follow a Nonlinear Dose Response

    Directory of Open Access Journals (Sweden)

    Hemantkumar Chavan

    2017-01-01

    Full Text Available Arsenite is a known carcinogen and its exposure has been implicated in a variety of noncarcinogenic health concerns. Increased oxidative stress is thought to be the primary cause of arsenite toxicity and the toxic effect is thought to be linear with detrimental effects reported at all concentrations of arsenite. But the paradigm of linear dose response in arsenite toxicity is shifting. In the present study we demonstrate that arsenite effects on mitochondrial respiration in primary hepatocytes follow a nonlinear dose response. In vitro exposure of primary hepatocytes to an environmentally relevant, moderate level of arsenite results in increased oxidant production that appears to arise from changes in the expression and activity of respiratory Complex I of the mitochondrial proton circuit. In primary hepatocytes the excess oxidant production appears to elicit adaptive responses that promote resistance to oxidative stress and a propensity to increased proliferation. Taken together, these results suggest a nonlinear dose-response characteristic of arsenite with low-dose arsenite promoting adaptive responses in a process known as mitohormesis, with transient increase in ROS levels acting as transducers of arsenite-induced mitohormesis.

  9. [Study on the interface of human hepatocyte/micropore polypropylene ultrafiltration membrane].

    Science.gov (United States)

    Peng, Cheng-Hong; Han, Bao-San; Gao, Chang-You; Ma, Zu-Wei; Zhao, Zhi-Ming; Wang, Yong; Liu, Hong; Zhang, Gui-di; Yang, Mei-Juan

    2004-09-02

    To found a new interface of human hepatocyte/micropore polypropylene ultrafiltration membrane (MPP) with good cytocompatibility so as to construct bioartificial bioreactor with polypropylene hollow fibers in future. MPP ultrafiltration membrane underwent chemical grafting modification through ultraviolet irradiation and Fe(2+) reduction. The contact angles of MPP and the modified MPP membranes were measured. Human hepatic cells L-02 were cultured. MPP and modified MPP membranes were spread on the wells of culture plate and human hepatic cells and cytodex 3 were inoculated on them. Different kinds of microscopy were used to observe the morphology of these cells. The water contact angle of MPP and the modified MPP membranes decreased from 78 degrees +/- 5 degrees to 27 degrees +/- 4 degrees (P < 0.05), which indicated that the hydrophilicity of the membrane was improved obviously after the grafting modification. Human hepatocyte L-02 did not adhere to and spread on the modified MPP membrane surface, and only grew on the microcarrier cytodex 3 with higher density and higher proliferation ratio measured by MTT. Grafting modification of acrylamide on MPP membrane is a good method to improve the human hepatocyte cytocompatibility with MPP ultrafiltration membrane.

  10. Ontogenetic changes in the ultrastructure of rat hepatocyte organelles after prenatal x irradiation

    International Nuclear Information System (INIS)

    Chedid, A.; Nair, V.

    1975-01-01

    The effects of prenatal x irradiation on the development of hepatocyte organelles have been studied in Sprague-Dawley rats. Pregnant rats received 50 R to the pelvic region on the 13th gestation day (g.d.). Animals were sacrificed on g.d.'s 15 and 20, day of birth, and 5th postnatal day. The fetal and neonatal livers were obtained and processed for electron-microscopic examination. The most striking discernible change after irradiation involves the appearance of cytoplasmic ''polyribosomal aggregates'' in the hepatocyte specimens of 15th and 20th g.d.'s. In the control rat, smooth endoplasmic reticulum (SER) appears for the first time on 20th g.d., while no SER could be detected in the hepatocytes from the irradiated animals at this period nor on day of birth. In the irradiated animals, SER was observed on the 5th postnatal day. Our results are consistent with the hypothesis that lipid peroxidation membrane alteration, delayed appearance of SER, and ''polyribosomal aggregation'' may be sequentially linked events after prenatal x irradiation. (U.S.)

  11. Effects of hepatocyte growth factor on glutathione synthesis, growth, and apoptosis is cell density-dependent

    International Nuclear Information System (INIS)

    Yang Heping; Magilnick, Nathaniel; Xia Meng; Lu, Shelly C.

    2008-01-01

    Hepatocyte growth factor (HGF) is a potent hepatocyte mitogen that exerts opposing effects depending on cell density. Glutathione (GSH) is the main non-protein thiol in mammalian cells that modulates growth and apoptosis. We previously showed that GSH level is inversely related to cell density of hepatocytes and is positively related to growth. Our current work examined whether HGF can modulate GSH synthesis in a cell density-dependent manner and how GSH in turn influence HGF's effects. We found HGF treatment of H4IIE cells increased cell GSH levels only under subconfluent density. The increase in cell GSH under low density was due to increased transcription of GSH synthetic enzymes. This correlated with increased protein levels and nuclear binding activities of c-Jun, c-Fos, p65, p50, Nrf1 and Nrf2 to the promoter region of these genes. HGF acts as a mitogen in H4IIE cells under low cell density and protects against tumor necrosis factor α (TNFα)-induced apoptosis by limiting JNK activation. However, HGF is pro-apoptotic under high cell density and exacerbates TNFα-induced apoptosis by potentiating JNK activation. The increase in cell GSH under low cell density allows HGF to exert its full mitogenic effect but is not necessary for its anti-apoptotic effect

  12. Study on radioprotection of alliin and damage mechanism in hepatocyte after irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Ji, Tae Jeong; Kim, Won Tae [Dept, of Radiological Science, Kaya University, Kimhae (Korea, Republic of)

    2016-12-15

    Liver tissue damage by a radiation exposure caused a jaundice and ascitic fluid e form harden atrophy. The reason for this lies in morphological damage of a liver cells. This study tried that observe damage mechanism of the cell organelles. It was especially observed mitochondria, endoplasmic reticulum and nuclear membrane associated with energy metabolizable. also, This study had with a radio-protector development research at the same time. Radio-protector was used to alliin that has an blood flow increase. Cell observation make used of transmission electron microscope(TEM). The result of an experiment, 7Gy of whole body irradiation was caused an inflammation in cell organelles and hypertrophy of the nucleus membrane. After 20 days, The hepatocyte has been observed in a damaged membrane on peroxisome, mitochondria and vacuole of the cell organelles. After 30 days, The hepatocyte has been observed in disconnected ribosomes on a rough endoplasmic reticulum. There was looked a giant lipoblast. There was clearly normal observed a mitochondria and nucleus membrane in the hepatocyte after alliin injection. aslo, It was no damaged the nucleus membrane. Therefore, It was identified portion a radio-protector effect from alliin.

  13. Synergistic toxicity of ethanol and MDMA towards primary cultured rat hepatocytes

    International Nuclear Information System (INIS)

    Pontes, Helena; Sousa, Carla; Silva, Renata; Fernandes, Eduarda; Carmo, Helena; Remiao, Fernando; Carvalho, Felix; Bastos, Maria Lourdes

    2008-01-01

    Ethanol is frequently consumed along with 3,4-methylenedioxymethamphetamine (MDMA; ecstasy). Since both compounds are hepatotoxic and are metabolized in the liver, an increased deleterious interaction resulting from the concomitant use of these two drugs seems plausible. Another important feature of MDMA-induced toxicity is hyperthermia, an effect known to be potentiated after continuous exposure to ethanol. Considering the potential deleterious interaction, the aim of the present study was to evaluate the hepatotoxic effects of ethanol and MDMA mixtures to primary cultured rat hepatocytes and to elucidate the mechanism(s) underlying this interaction. For this purpose, the toxicity induced by MDMA to primary cultured rat hepatocytes in absence or in presence of ethanol was evaluated, under normothermic (36.5 deg. C) and hyperthermic (40.5 deg. C) conditions. While MDMA and ethanol, by themselves, had discrete effects on the analysed parameters, which were slightly aggravated under hyperthermia, the simultaneous incubation of MDMA and ethanol for 24 h, resulted in high cell death ratios accompanied by a significant disturbance of cellular redox status and decreased energy levels. Evaluation of apoptotic/necrotic features provided clear evidences that the cell death occurs preferentially through a necrotic pathway. All the evaluated parameters were dramatically aggravated when cells were incubated under hyperthermia. In conclusion, co-exposure of hepatocytes to ethanol and MDMA definitely results in a synergism of the hepatotoxic effects, through a disruption of the cellular redox status and enhanced cell death by a necrotic pathway in a temperature-dependent extent

  14. The homeobox gene Hex regulates hepatocyte differentiation from embryonic stem cell-derived endoderm.

    Science.gov (United States)

    Kubo, Atsushi; Kim, Yon Hui; Irion, Stefan; Kasuda, Shogo; Takeuchi, Mitsuaki; Ohashi, Kazuo; Iwano, Masayuki; Dohi, Yoshiko; Saito, Yoshihiko; Snodgrass, Ralph; Keller, Gordon

    2010-02-01

    We investigated the role of the hematopoietically expressed homeobox (Hex) in the differentiation and development of hepatocytes within embryonic stem cell (ESC)-derived embryoid bodies (EBs). Analyses of hepatic endoderm derived from Hex(-/-) EBs revealed a dramatic reduction in the levels of albumin (Alb) and alpha-fetoprotein (Afp) expression. In contrast, stage-specific forced expression of Hex in EBs from wild-type ESCs led to the up-regulation of Alb and Afp expression and secretion of Alb and transferrin. These inductive effects were restricted to c-kit(+) endoderm-enriched EB-derived populations, suggesting that Hex functions at the level of hepatic specification of endoderm in this model. Microarray analysis revealed that Hex regulated the expression of a broad spectrum of hepatocyte-related genes, including fibrinogens, apolipoproteins, and cytochromes. When added to the endoderm-induced EBs, bone morphogenetic protein 4 acted synergistically with Hex in the induction of expression of Alb, Afp, carbamoyl phosphate synthetase, transcription factor 1, and CCAAT/enhancer binding protein alpha. These findings indicate that Hex plays a pivotal role during induction of liver development from endoderm in this in vitro model and suggest that this strategy may provide important insight into the generation of functional hepatocytes from ESCs.

  15. Purification, characterisation and protective effects of polysaccharides from alfalfa on hepatocytes.

    Science.gov (United States)

    Wang, Shaopu; Dong, Xiaofang; Ma, Hao; Cui, Yaoming; Tong, Jianming

    2014-11-04

    The objective of this study was to determine the preliminary characteristics and protective effects of alfalfa polysaccharides (APS) on hepatocytes in vitro. The crude APS was purified by DEAE-cellulose and Sephadex G-100 chromatography, resulting in the four purified fractions: APS-1, APS-2, APS-3 and APS-4. The results indicated that APS-3 had higher carbohydrate and uronic acid contents and that APS-4 had a more complicated monosaccharide composition compared to the other purified fractions. The average molecular weights of APS-1, APS-2, APS-3 and APS-4 were 48,536, 6,221, 66,559 and 13,076 Da, respectively. Furthermore, APS (crude and its purified fractions) restored the activities of antioxidant enzymes and increased the total antioxidant capacity of hepatocytes subjected to H2O2-induced oxidative stress. Furthermore, APS treatment counteracted the increases in lactic dehydrogenase and malonaldehyde in the culture supernatant. These results clearly demonstrate that APS possesses a protective effect against oxidative injury in hepatocytes. Copyright © 2014 Elsevier Ltd. All rights reserved.

  16. Exosome RNA Released by Hepatocytes Regulates Innate Immune Responses to Hepatitis B Virus Infection

    Directory of Open Access Journals (Sweden)

    Takahisa Kouwaki

    2016-08-01

    Full Text Available The innate immune system is essential for controlling viral infection. Hepatitis B virus (HBV persistently infects human hepatocytes and causes hepatocellular carcinoma. However, the innate immune response to HBV infection in vivo remains unclear. Using a tree shrew animal model, we showed that HBV infection induced hepatic interferon (IFN-γ expression during early infection. Our in vitro study demonstrated that hepatic NK cells produced IFN-γ in response to HBV only in the presence of hepatic F4/80+ cells. Moreover, extracellular vesicles released from HBV-infected hepatocytes contained viral nucleic acids and induced NKG2D ligand expression in macrophages by stimulating MyD88, TICAM-1, and MAVS-dependent pathways. In addition, depletion of exosomes from extracellular vesicles markedly reduced NKG2D ligand expression, suggesting the importance of exosomes for NK cell activation. In contrast, infection of hepatocytes with HBV increased immunoregulatory microRNA levels in extracellular vesicles and exosomes, which were transferred to macrophages, thereby suppressing IL-12p35 mRNA expression in macrophages to counteract the host innate immune response. IFN-γ increased the hepatic expression of DDX60 and augmented the DDX60-dependent degradation of cytoplasmic HBV RNA. Our results elucidated the crucial role of exosomes in antiviral innate immune response against HBV.

  17. Statins, PCSK9 inhibitors and cholesterol homeostasis: a view from within the hepatocyte.

    Science.gov (United States)

    Sniderman, Allan D; Kiss, Robert Scott; Reid, Thomas; Thanassoulis, George; Watts, Gerald F

    2017-05-01

    Statins and PCSK9 inhibitors dramatically lower plasma LDL levels and dramatically increase LDL receptor number within hepatocyte cell membranes. It seems self-evident that total clearance of LDL particles from plasma and total delivery of cholesterol to the liver must increase in consequence. However, based on the results of stable isotope tracer studies, this analysis demonstrates the contrary to be the case. Statins do not change the production rate of LDL particles. Accordingly, at steady state, the clearance rate cannot change. Because LDL particles contain less cholesterol on statin therapy, the delivery of cholesterol to the liver must, therefore, be reduced. PCSK9 inhibitors reduce the production of LDL particles and this further reduces cholesterol delivery to the liver. With both agents, a larger fraction of a smaller pool is removed per unit time. These findings are inconsistent with the conventional model of cholesterol homeostasis within the liver, but are consistent with a new model of regulation, the multi-channel model, which postulates that different lipoprotein particles enter the hepatocyte by different routes and have different metabolic fates within the hepatocyte. The multi-channel model, but not the conventional model, may explain how statins and PCSK9 inhibitors can produce sustained increases in LDL receptor number. © 2017 The Author(s); published by Portland Press Limited on behalf of the Biochemical Society.

  18. Cholesterol crystallization within hepatocyte lipid droplets and its role in murine NASH.

    Science.gov (United States)

    Ioannou, George N; Subramanian, Savitha; Chait, Alan; Haigh, W Geoffrey; Yeh, Matthew M; Farrell, Geoffrey C; Lee, Sum P; Savard, Christopher

    2017-06-01

    We recently reported that cholesterol crystals form in hepatocyte lipid droplets (LDs) in human and experimental nonalcoholic steatohepatitis. Herein, we assigned WT C57BL/6J mice to a high-fat (15%) diet for 6 months, supplemented with 0%, 0.25%, 0.5%, 0.75%, or 1% dietary cholesterol. Increasing dietary cholesterol led to cholesterol loading of the liver, but not of adipose tissue, resulting in fibrosing steatohepatitis at a dietary cholesterol concentration of ≥0.5%, whereas mice on lower-cholesterol diets developed only simple steatosis. Hepatic cholesterol crystals and crown-like structures also developed at a dietary cholesterol concentration ≥0.5%. Crown-like structures consisted of activated Kupffer cells (KCs) staining positive for NLRP3 and activated caspase 1, which surrounded and processed cholesterol crystal-containing remnant LDs of dead hepatocytes. The KCs processed LDs at the center of crown-like structures in the extracellular space by lysosomal enzymes, ultimately transforming into lipid-laden foam cells. When HepG2 cells were exposed to LDL cholesterol, they developed cholesterol crystals in LD membranes, which caused activation of THP1 cells (macrophages) grown in coculture; upregulation of TNF-alpha , NLRP3, and interleukin 1beta ( IL1β ) mRNA; and secretion of IL-1beta. In conclusion, cholesterol crystals form on the LD membrane of hepatocytes and cause activation and cholesterol loading of KCs that surround and process these LDs by lysosomal enzymes.

  19. Trichostatin A, a critical factor in maintaining the functional differentiation of primary cultured rat hepatocytes

    International Nuclear Information System (INIS)

    Henkens, Tom; Papeleu, Peggy; Elaut, Greetje; Vinken, Mathieu; Rogiers, Vera; Vanhaecke, Tamara

    2007-01-01

    Histone deacetylase inhibitors (HDI) have been shown to increase differentiation-related gene expression in several tumor-derived cell lines by hyperacetylating core histones. Effects of HDI on primary cultured cells, however, have hardly been investigated. In the present study, the ability of trichostatin A (TSA), a prototype hydroxamate HDI, to counteract the loss of liver-specific functions in primary rat hepatocyte cultures has been investigated. Upon exposure to TSA, it was found that the cell viability of the cultured hepatocytes and their albumin secretion as a function of culture time were increased. TSA-treated hepatocytes also better maintained cytochrome P450 (CYP)-mediated phase I biotransformation capacity, whereas the activity of phase II glutathione S-transferases (GST) was not affected. Western blot and qRT-PCR analysis of CYP1A1, CYP2B1 and CYP3A11 protein and mRNA levels, respectively, further revealed that TSA acts at the transcriptional level. In addition, protein expression levels of the liver-enriched transcription factors (LETFs) hepatic nuclear factor 4 alpha (HNF4α) and CCAAT/enhancer binding protein alpha (C/EBPα) were accordingly increased by TSA throughout culture time. In conclusion, these findings indicate that TSA plays a major role in the preservation of the differentiated hepatic phenotype in culture. It is suggested that the effects of TSA on CYP gene expression are mediated via controlling the expression of LETFs

  20. Evaluation of Medicinal Plant Hepatotoxicity in Co-cultures of Hepatocytes and Monocytes

    Directory of Open Access Journals (Sweden)

    Bashar Saad

    2006-01-01

    Full Text Available Non-parenchymal cells might play an important role in the modulation of xenobiotic metabolism in liver and its pharmacological and toxicological consequences. Therefore, the role of cell-to-cell interactions in herbal induced liver toxicity was investigated in monocultures of cells from the human hepatocyte cell line (HepG2 and in co-cultures of cells from the HepG2 cell line and cells from the human monocyte cell line (THP1. Cells were treated with various concentrations (1–500 µg ml−1 of extracts of Pistacia palaestina, Juglans regia and Quercus ithaburensis for 24 h. Extracts from Cleome droserifolia, a known toxic plant, were taken as positive control. In the co-culture system, toxic effects were observed after exposure to extracts of Pistacia palestina and C. droserifolia. These two extracts significantly reduced by cell viability as measured the MTT test and the LDH assay. Whereas in hepatocyte cultures, only extracts of C. droserifolia were found to affect the cell viability. The production levels of albumin from hepatocytes were not affected by treatment with plant extracts in both culture systems. It seems that the observed reduction in cell viability after exposure to extracts of P. palestina in co-cultures but not in monocultures is a result of monocyte-derived factors. The use of liver cell co-cultures is therefore a useful approach to investigate the influence of intercellular communication on xenobiotic metabolism in liver.