bluuebunny/crossref_metadata_2025 huggingface dataset:
Alteration of xanthine oxidase activity in sinusoidal endothelial cells and morphological changes of kupffer cells in hypoxic and reoxygenated rat liver
Authors: Angermüller Sabine , Schunk Marcus , Kusterer Klaus
Published: March 2007

In the model of the perfused rat liver, we investigated the alterations of sinusoidal cells in the pathogenesis of liver injury caused by hypoxia and reperfusion. In sinusoidal endothelial cells, the activity of xanthine oxidase (XOX), a cytoplasmic marker enzyme, was located cytochemically and determined biochemically. Kupffer cells, identified by their endogenous peroxidase staining, were studied with regard to changes in their ultrastructure. In our experiments, parenchymal cells were shown to be severely damaged in contrast to sinusoidal lining cells, which showed minor signs of injury. In comparison with the control group, XOX activity increased significantly in the sinusoidal endothelial cells after low-flow hypoxia; however, after reoxygenation of only 5 minutes, that activity was lower after hypoxia but higher after control perfusion. In Kupffer cells, hypoxia resulted in a strong suppression of phagocytic and endocytotic activity and in a disappearance of the lamellopodia. Kupffer cells were flattened, resembling sinusoidal endothelial cells. After reoxygenation phagocytic vesicles, lamellopodia, and cell volume of Kupffer cells increased markedly in comparison with the control group. In the hypoxia/reperfusion injury model, our observations revealed significant alterations of sinusoidal lining cells. It appears that sinusoidal endothelial cells respond to the hypoxic phase by producing oxygen-derived free radicals and that Kupffer cells respond to the subsequent reperfusion phase by activation followed by the release of toxic mediators.
Monitoring of surface mitochondrial nadh levels as an indication of ischemia during liver isograft transplantation
Authors: Thorniley Maureen S. , Simpkin Sandra , Fuller Barry , Jenabzadeh Mandana Z. , Green Colin J.
Published: March 2007

Ischemia-reperfusion injury is a major cause of transplant dysfunction. One feature of this damage is mitochondrial dysfunction. The objective of this study was to determine whether surface fluorometric measurements of mitochondrial NADH can be made, and if the technique can detect differences in mitochondrial respiration between minimally stored 1 to 2°C for 25 minutes (group 1, control) transplanted livers and those stored in hypertonic citrate at 1 to 2°C (group 2) for 24 hours before transplantation. Measurements were made in livers isografted in 20 male Lewis rats. The technique is sufficiently sensitive to detect increased (nicotinamideadenine dinucleotide (NADH) during dissection of hepatic vessels before ligation 0.52 ± 0.04 (n = 14, P < 0.03) compared with the in situ exposed liver, 0.43 ± 0.02 n = 14). Complete hepatic ligation resulted in a significant increase in NADH (1.22 ± 0.10, n = 14), P < 0.0001) compared with hepatic artery ligation, which did not increase NADH levels. After storage, NADH levels increased (P < 0.02) but there was no significant difference between groups. In group 1, completion of portal vein (PV), suprahepatic vena cava (SVC), and descending vena cava anastomoses resulted in decreased NADH levels toward those after preparation of the vessels before ligation. However, there was a significant difference (P < 0.004) between the 25-minute and the 24-hour stored livers, 0.56 ± 0.07 versus 0.23 ± 0.04, respectively. On final revascularisation, NADH returned to preligation values in group 1 but there was a highly significant difference between groups 1 (0.42 ± 0.03) and 2 (0.22 ± 0.02) (P < 0.0003) equivalent to 89% and 100% oxidation. This abnormal maximal level of NADH oxidation (100%) in the 24-hour stored livers is suggestive of mitochondrial dysfunction. These results show that it might be possible to predict organ viability by noninvasive measurements of respiratory chain dysfunction in the clinical transplant situation.
Interaction of human gallbladder mucin with calcium hydroxyapatite: Binding studies and the effect on hydroxyapatite formation
Authors: Qiu Sui-Min , Wen Gary , Wen Julie , Soloway Roger D. , Crowther Roger S.
Published: March 2007

Calcium hydroxyapatite (HAP) crystals formed in vitro in the presence of polymeric human gallbladder mucin (1.0 mg/mL) were smaller (0.75 ± 0.39 μm) than control crystals (7.86 ± 2.76 μm), but the mucin did not affect the kinetics of crystal formation or alter the amount of mineral phase present at equilibrium. In contrast, glycopeptide subunits produced by proteolysis of the native mucin had no effect on HAP crystal size. Both native mucin and glycopeptides bound to mature HAP crystals, but the glycopeptides were much more readily displaced by phosphate ions. Therefore, in experiments where HAP was being formed, the phosphate ions inhibited the interaction of glycopeptides with the nascent HAP. These results indicate that gallbladder mucin may modulate HAP formation in vivo, and that this ability may be altered during pathological states, such as neutrophil infiltration or bacterial colonization, that may cause the release of proteinases capable of digesting mucin.
Effects of acetaldehyde on nuclear protein binding to the nuclear factor I consensus sequence in the α2(I) collagen promoter
Authors: Anania Frank A. , Potter James J. , Rennie-Tankersley Lynda , Mezey Esteban
Published: March 2007

Acetaldehyde has been shown to increase collagen production in cultured rat myofibroblastlike cells and to activate the mouse α2(I) collagen promoter in transfected NIH 3T3 cells. Nuclear factor I (NF-I), a CCAAT binding transcription factor, is known to bind and activate the α(I) and α2(I) collagen genes. Activation of the α2(I) collagen promoter was not observed when the NF-I binding site of the promoter was deleted. In this study, we determined if acetaldehyde influences the binding of NF-I to the α2(I) collagen promoter. Nuclear proteins extracted from NIH 3T3 cells, or myofibroblastlike cells, 36 hours after the addition of acetaldehyde (200 μmol/L) in serum-free media showed increased binding to the consensus sequence of the NF-I binding site by DNase I protection analysis and by electrophoretic mobility shift assay (EMSA) as compared with control nuclear extracts that were not exposed to acetaldehyde. Furthermore, nuclear proteins extracted from myofibroblastlike cells that had been previously exposed to acetaldehyde had a marked increase in NF-I protein, as shown by Western blot with NF-I antibodies. Antisera to NF-I resulted in a slow migrating DNA-protein-antibody complex (supershift) on EMSA. However, the NF-I antibody did not supershift all the DNA-protein complexes, and the supershift band was not increased with nuclear proteins from acetaldehyde-treated cells despite the increased binding of these nuclear protein preparations to the NF-I oligo. Therefore, nuclear proteins, in addition to NF-I, bind to the NF-I consensus sequence and may have their binding altered by acetaldehyde. No supershift was obtained with antisera to Histone H1, which is known to also bind to the consensus sequence for NF-I in this promoter. This study suggests that the effect of acetaldehyde in enhancing transcription of the α2(I) collagen promoter may be mediated by binding of NF-I or NF-I—like proteins to the promoter, but may also include additional CCAAT binding proteins.
Different hepatocytes express the cholesterol 7α-hydroxylase gene during its circadian modulation in vivo
Authors: Berkowitz Caryn M. , Shen Cynthia S. , Bilir Bahri M. , Guibert Edgardo , Gumucio Jorge J.
Published: March 2007

Cholesterol 7α-hydroxylase, the rate-limiting enzyme in bile salt synthesis from cholesterol is a P450 enzyme (CYP7A). Its expression and activity are regulated by bile salts, cholesterol, hormones and a circadian modulator. Here we define the hepatocytes contributing to the expression of the rat CYP7A gene during its in vivo circadian variation. The diurnal expression of the CYP7A messenger RNA (mRNA) was studied by in situ hybridization and correlated with the diurnal rate of CYP7A gene transcription and mRNA expression. At 10 AM, the time of lowest mRNA expression and gene transcription rate, only four to five hepatocytes, located close to the hepatic venules (“perivenular”), contained the CYP7A mRNA. At 10 PM, the time of highest mRNA expression and fastest in vitro transcription rate, approximately one half of the hepatocytes (still in a “perivenular” location) contained the cholesterol 7α-hydroxylase mRNA. In addition, the measured half-life of the CYP7A mRNA was shorter at 10 AM than at 10 PM suggesting that posttranscriptional mechanisms also contributed to the observed circadian differences. Therefore, the basal transcription rate of the CYP7A gene is maintained by four to five “perivenular” hepatocytes. During the circadian variation, the rate of gene transcription increases in these “perivenular” hepatocytes, but in addition, there is recruitment of other more proximal hepatocytes to transcribe the gene. It is proposed here that the response of specific hepatocytes to the various modulators of CYP7A gene expression is dependent on the relative position of these hepatocytes within the liver cell plate.
Roles of prostaglandin production and mitogen-activated protein kinase activation in hepatocyte growth factor—mediated rat hepatocyte proliferation
Authors: Adachi Takahito , Nakashima Shigeru , Saji Shigetoyo , Nakamura Toshikazu , Nozawa Yoshinori
Published: March 2007

Hepatocyte growth factor (HGF) and epidermal growth factor (EGF)—stimulated DNA synthesis in primary cultured rat hepatocytes. HGF-induced DNA synthesis was concentration-dependently inhibited by a cyclooxygenase inhibitor, indomethacin. BW755C, a dual inhibitor for cyclooxygenase and lipoxygenase activities, also inhibited hepatocyte growth. Prostaglandin E1 (PGE1), PGE2, and PGF2α induced DNA synthesis even at such a low concentration as 5 nmol/L and potentiated [3H]thymidine incorporation induced by HGF in an additive manner. HGF caused arachidonic acid (AA) release and eicosanoid production. These events were detectable within 10 minutes after stimulation and lasted for at least 60 minutes. Furthermore, two proteins with approximately 40 kd were tyrosine phosphorylated by HGF. These proteins were identified as p42/p44 mitogen-activated protein (MAP) kinases by anti-MAP kinase immunoblots, which were known to activate cytosolic phospholipase A2 (cPLA2), a key enzyme in AA release. Activation of MAP kinases was detectable within 5 minutes after stimulation with HGF and lasted for at least 60 minutes. FGF-mediated DNA synthesis was also inhibited by the above cyclooxygenase inhibitors. EGF caused AA release and tyrosine phosphorylation of MAP kinases. These results suggest that HGF as well as EGF causes AA release, probably through activation of cPLA2 mediated by MAP kinases, and that PGs, metabolites of AA, might play a pivotal role in hepatocyte proliferation in an autocrine mechanism.
Regulation of human Gc (vitamin D — binding) protein levels: Hormonal and cytokine control of gene expression in vitro
Authors: Guha Chandan , Osawa Motoki , Werner Phillip A. , Galbraith Robert M. , Paddock Gary V.
Published: March 2007

Studies were performed in Hep3B hepatocytes to better elucidate the mechanisms regulating circulating levels of human group—specific component (Gc). We measured changes in Gc messenger RNA (mRNA) synthesis and levels of secreted protein resulting from treatment of hepatocytes with cytokines and hormones known to influence synthesis of other proteins of hepatic origin. We particularly focused on compounds known to be prototypic stimulants during the acute phase response. Interleukin-6 (IL-6) and dexamethasone were shown to increase Gc mRNA approximately twofold while transforming growth factor beta (TGFβ) decreased Gc mRNA in a dose-dependent fashion by up to fivefold. The effects on secreted Gc protein levels were similar. These results indicate that Gc protein appears to be regulated differently than the other members of this gene family, albumin and alpha-fetoprotein (AFP), which are negative acute phase reactants. In addition, these contrasting effects on Gc synthesis of IL-6 and dexamethasone and of TGFβ suggest that high basal levels of Gc synthesis may be maintained during the acute phase response.
Alterations in messenger rna encoding atrial natriuretic hormone receptor A and C subtypes during hepatic regeneration
Authors: Patel Tarun B. , Nair Bipin G. , Padmini Ekambaram , Rashed Hani M. , Sun Hui
Published: March 2007

Previously, we demonstrated that, 48 hours after partial hepatectomy, in the regenerating liver the number of both atrial natriuretic hormone (ANF) receptor subtypes, the guanylyl cyclase—linked and ANF-C receptors, is increased twofold. Subsequently, we demonstrated that activation of ANF-C receptors inhibits growth of hepatocytes. Therefore, studies were performed to determine whether, during hepatic regeneration, the increase in ANF receptor subtypes is accompanied by an increase in their respective transcripts. Our data demonstrate that in the normal and regenerating rat liver, the predominant guanylyl cyclase—linked ANF receptor is of the ANF-A subtype. Moreover, messenger RNA (mRNA) encoding the ANF-A and ANF-C receptors are transiently increased after surgery; the levels of mRNA encoding both receptor subtypes remain unchanged in livers of sham-operated animals. ANF-A receptor mRNA is maximally increased 12 hours after partial hepatectomy, whereas the maximal increase in ANF-C receptor mRNA is observed between 0.5 hour and 4 hours after hepatectomy. The increase in ANF-C receptor transcript is accompanied by increased expression of protein, 4 hours after hepatectomy. However, the ANF-C receptor protein is also elevated 48 hours after partial hepatectomy when ANF-C receptor mRNA levels are not different from controls. Likewise, although ANF-A receptors are increased when hepatic levels of mRNA encoding the protein are maximally elevated, the maximal increase in ANF-A receptor protein occurs at times when transcript levels are low and similar to those in sham-operated controls. These findings demonstrate differential regulation in the expression of ANF-A and ANF-C receptors and are illustrative of regulation of expression of both receptors at the translational or posttranslational levels.
The number and distribution of hepatic natural killer cells (pit cells) in normal rat liver: An immunohistochemical study
Authors: Luo Dianzhong , Vanderkerken Karin , Bouwens Luc , Kuppen Peter J. K. , Crabbé Evelyne , Wisse Eddie
Published: March 2007

Pit cells are a unique population of cells in sinusoids and peripheral blood, which can be considered natural killer (NK) cells with large granular lymphocyte (LGL) morphology. The aim of this study was to investigate the use of the monoclonal antibody (MAb) 3.2.3 as a specific marker of rat pit cells to detect their number and distribution in the liver. The number of 3.2.3-positive cells was comparable to the number of LGL in liver low-density (LD) and high-density (HD) pit cell fractions and in blood lymphocytes (P > 0.05). Immunoelectron microscopy showed that nearly all LGL in hepatic LD and HD and in blood fractions were 3.2.3 positive. Using MAb 3.2.3 immunoperoxidase staining, the mean number of pit cells in liver frozen sections was determined to be 13.7 ± 1.1/mm2. The number of pit cells was similar in the different liver lobes (P > 0.05). Reduced nicotinamide-adenine dinucleotide (NADH) oxidase histochemical staining, to visualize a portal to central vein gradient, combined with immunostaining was used to analyze the lobular distribution of pit cells. We found that 61.3% (17.1/mm2) of pit cells were in the periportal area and 38.7% (10.8/mm2) in the central area. We conclude that MAb 3.2.3 can be used as a specific marker of rat pit cells and therefore can be used to quantify rat pit cell number in various experimental models.
Immediate early detection of urokinase receptor after partial hepatectomy and its implications for initiation of liver regeneration
Authors: Mars Wendy M. , Liu Meng-Lun , Kitson Richard P. , Goldfarb Ronald H. , Gabauer Megan K. , Michalopoulos George K.
Published: March 2007

Hepatocyte growth factor (HGF), also known as scatter factor, is believed to play a primary role in liver regeneration. HGF is produced in an inactive single-chain form that can be cleaved in vitro to the active two-chain form by tissue-type and urokinase-type plasminogen (PLG) activators (tPA and uPA). We have now documented the de novo appearance of active uPA in livers from male Fischer F344 rats that underwent 70% partial hepatectomy (PHx) as early as 1 minute after surgery. Western blot analyses of protein extracts from liver remnants that were obtained immediately after surgery and periodically until 24 hours after PHx indicate that the quantity of uPA remains fairly constant in PHx samples. In contrast, the uPA receptor (uPAR) dramatically increases, beginning within 1 minute after PHx. This results in enhanced activity of uPA, as seen by direct zymography on cryostat sections. The uPA present in remnant liver homogenates from rats that underwent PHx is the primary agent that cleaves single-chain HGF to its two-chain form, because cleavage can be prevented when antibody against uPA is included in the liver homogenates. Furthermore, heterodimeric HGF, which is not present in normal liver, increases in the liver remnants from rats that underwent PHx, correlative to uPAR. The presence of active uPA is one of the earliest responses yet documented after PHx. These findings imply that both uPA and uPAR are involved in activating endogenous HGF in the regenerating livers of animals that underwent PHx.
Effect of selective bowel decontamination with norfloxacin on spontaneous bacterial peritonitis, translocation, and survival in an animal model of cirrhosis
Authors: Runyon Bruce A. , Borzio Mauro , Young Sharon , Squier Susan U. , Guarner Carlos , Runyon Michelle A.
Published: March 2007

Selective bowel decontamination with the orally administered quinolone antibiotic, norfloxacin, has been shown to suppress gut gram-negative bacteria and help prevent gram-negative infections in cirrhotic patients who are at high risk of bacterial infection. Because this drug does not eradicate gram-positive organisms, it is conceivable that gram-positives could replace the suppressed gram-negatives in the gut and lead to subsequent infection. Also the effect of norfloxacin on translocation (as defined by culture positivity of mesenteric lymph nodes) has received little attention. In this study, the effect of oral norfloxacin on translocation, bacterial peritonitis, and survival was investigated in an animal model of carbon tetrachloride—induced cirrhosis and ascites. Treated rats received daily doses of orally administered norfloxacin from the onset of cirrhosis until they died or were killed. Controls received no antibiotic. Norfloxacin led to a reduction in bacterial peritonitis from 70% in untreated cirrhotic controls to 28% in treated cirrhotic rats; these data were statistically significant (P = 0.012). There was no effect on overall translocation rate (28% with norfloxacin vs. 50% without norfloxacin) (P > 0.1). Gram-positives were isolated in 100% of the bacterial peritonitis episodes and in 71.4% of culture-positive mesenteric lymph nodes in treated animals compared with only 25% of peritonitis episodes and 10% of culture-positive mesenteric lymph nodes of untreated cirrhotic controls (P < 0.01 for peritonitis and P < 0.05 for translocation). The survival rate was not different between groups (P > 0.1). Although norfloxacin was associated with a 60% reduction in the overall rate of peritonitis, this drug increased the risk of gram-positive translocation and gram-positive peritonitis, and did not prolong survival in this animal model.
DNA damage and donor livers: Disease unbidden?
Authors: Schwarz Kathleen
Published: March 2007

Endogenous DNA adducts may contribute to the etiology of human genetic disease and cancer. One potential source of endogenous DNA adducts is lipid peroxidation, which generates mutagenic carbonyl compounds such as malondialdehyde. A sensitive mass spectrometric method permitted detection and quantitation of the major malondialdehyde-DNA adduct, a pyrimidopurinone derived from deoxyguanosine. DNA from disease-free human liver was found to contain 5400 adducts per cell, a frequency comparable to that of adducts formed by exogenous carcinogens. Reprinted with permission from Science 1994;265:1580-1581.
Molecular mechanism of hepatocellular injury in alpha1 antitrypsin deficiency
Authors: Askari Frederick K.
Published: March 2007

Liver injury in PiZZ α1-antitrypsin (α1-AT) deficiency probably results from toxic effects of the abnormal α1-AT molecule accumulating within the ER of liver cells. However, only 12-15% of individuals with this same genotype develops liver disease. Therefore, we predicted that other genetic traits that determine the net intracellular accumulation of the mutant α1-AT molecule would also determine susceptibility to liver disease. To address this prediction, we transduced skin fibroblasts from PiZZ individuals with liver disease or without liver disease with amphotropic recombinant retroviral particles designed for constitutive expression of the mutant α1-AT Z gene. Human skin fibroblasts do not express the endogenous α1-AT gene but presumably express other genes involved in postsynthetic processing of secretory proteins. The results show that expression of human α1-AT M gene was conferred on each fibroblast cell line. Compared to the same cell line transduced with the wild-type α1-AT M gene, there was selective intracellular accumulation of the mutant α1-AT Z protein in each case. However, there was a marked delay in degradation of the mutant α1-AT Z protein after it accumulated in the fibroblasts from ZZ individuals with liver disease (“susceptible hosts”) as compared to those without liver disease (“protected hosts”). Appropriate disease controls showed that the lag in degradation in susceptible hosts is specific for the combination of PiZZ phenotype and liver disease. Biochemical characteristics of α1-AT Z degradation in the protected hosts were found to be similar to those of a common ER degradation pathway previously described in model experimental cell systems for T-cell receptor α subunits and asialoglycoprotein receptor subunits, therefore, raising the possibility that the lag in degradation in the susceptible host is a defect in this common ER degradation pathway. Thus, these data provide evidence that other genetic traits that affect the fate of the abnormal α1-AT Z molecule, at least in part, determine susceptibility to liver disease. These data also validate a system for elucidating the biochemical/genetic characteristics of these traits and for examining the relevance to human disease of pathways for protein déradation in the ER.
Persistent hepatitis C virus infection after liver transplantation: Clinical and virological features
Authors: Gretch David R. , Bacchi Carlos E. , Corey Lawrence , Rosa Corazon Dela , Lesniewski Richard R. , Kowdley Kris , Gown Allen , Frank Indra , Perkins James D. , Carithers Robert L.
Published: March 2007

We report a prospective clinical and virological study of 18 patients undergoing orthotopic liver transplantation, selected because of hepatitis C virus (HCV) RNA positivity before transplantation. Nine of the 18 patients (50%) developed chronic active hepatitis (CAH) in liver allografts during the first year posttransplantation; hepatitis was first observed between 6 and 25 weeks post-transplantation. HCV viremia was measured for all patients before transplantation and on posttransplantation days 3, 7, and 14, and months 1, 6, 12, and 24 to 41, by quantitative competitive RNA polymerase chain reaction (QC-PCR). HCV RNA levels on posttransplantation days 3, 7, and 14 were significantly higher among patients who subsequently developed CAH versus those who did not (P < .02 by t-test and Mann-Whitney test on all three dates). However, HCV RNA levels in sera obtained at 1, 6, and 12 months posttransplantation did not correlate with CAH at 1 year or with HCV genotype determined in posttransplantation sera. At least two serial liver biopsy specimens from each patient were stained for HCV nonstructural 4 (NS4) antigen by immunohistochemistry. The intensity of cytoplasmic staining of NS4 antigen was significantly higher for specimens with CAH versus those without CAH (P = .028 by λ<2>). Three patients developed bridging fibrosis in liver allografts during the first year after transplantation; all three patients had intense (3+) immunostaining for NS4 antigen, and the infecting genotypes were 1a, 1b, and 1a plus 1b, respectively. In summary, the 18 patients all developed high-titer viremia by 1 month after liver transplantation, whereas CAH developed in 50% of allografts during the first year after transplantation. Patients with recurrent CAH were characterized by higher HCV RNA titers during the first 2 weeks posttransplantation and increased staining of HCV NS4 antigen in diseased liver biopsy specimens; however, the role of virological factors in the recurrence of CAH after liver transplantation remains uncertain. (Hepatology 1995; 22:1-9.)
In vivo and in vitro expression of defective hepatitis B virus particles generated by spliced hepatitis B virus RNA
Authors: Rosmorduc Olivier , Petit Marie-Anne , Pol Stanislas , Capel Francis , Bortolotti Flavia , Berthelot Pierre , Brechot Christian , Kremsdorf Dina
Published: March 2007

The mechanisms involved in hepatitis B virus (HBV) persistence are still poorly understood. We have previously shown that the encapsidation of the singly spliced 2.2 kb-HBV RNA leads to the secretion of circulating HBV defective particles in patients with chronic hepatitis. We have now investigated the presence of the HBV defective particles in sera from patients with acute and chronic hepatitis, using polymerase chain reaction. These defective particles were detected in a larger amount in sera of patients with acute hepatitis that progressed to chronic hepatitis, or had already developed chronic hepatitis, as compared with those who recovered from acute hepatitis (the increase was estimated to be an average of 50-fold). In addition, we showed that the presence of these defective HBV particles is closely associated with the chronic course of hepatitis B virus infection and with viral multiplication. We also analyzed viral RNAs and proteins synthetized after in vitro transfection of Huh7 cell line with the corresponding defective hepatitis B virus DNA molecule. We showed that expression of the defective hepatitis B virus DNA alone leads to a marked intracellular accumulation of the major core protein (HBcAg) and to an increased secretion of hepatitis B e antigen (HBeAg). These observations may be consistent with a role of these defective hepatitis B virus (HBV) particles in viral persistence. (Hepatology 1995;21:10-19.)
Diversity of quasispecies in various disease stages of chronic hepatitis C virus infection and its significance in interferon treatment
Authors: Koizumi Kazuhiko , Enomoto Nobuyuki , Kurosaki Masayuki , Murakami Takeshi , Izumi Namiki , Marumo Fumiaki , Sato Chifumi
Published: March 2007

Hepatitis C virus (HCV) populations in vivo exist as a mixture of heterogeneous viruses called quasispecies, which have variations in the hypervariable region (HVR). However, the relationship between the diversity of HVR quasispecies, the disease stage, or the interferon (IFN) responsiveness remains to be elucidated. To study these, serum samples were obtained from 42 patients with chronic hepatitis C virus infection;24 with chronic active hepatitis (CAH) treated with IFN, 9 with cirrhosis, 9 with hepatocellular carcinoma (HCC). HCV quasispecies populations were separated by the single-strand conformation polymorphism (SSCP) method targeted to the HVR. The patients were classified into two groups; a single-band group (n = 12) in which HVR quasispecies was homogeneous and a multiple-band group (n = 30) in which HVR quasispecies was heterogeneous. Patients with multiple bands had significantly more advanced liver disease than those with a single-band group (P = .0082). The percentage of patients with single band were 41% in CAH, 22% in cirrhosis, and 0% in HCC. Multi-variate analyses showed that viral diversity was independently related to the progression of liver disease and was not correlated with the duration of infection. We also found that in CAH, the patients who had multiple bands (n = 14) were more resistant to IFN therapy than those who had a single band (n = 10) (P = .002). These results indicate that the diversity of HCV quasispecies becomes more complex as the disease stage progresses and that CAH with more complex diversity shows less IFN effectiveness. (Hepatology 1995;22:30-35.)
Effect of immunosuppressive and antiviral agents on hepatitis B virus replication in vitro
Authors: McMillan Janine S. , Shaw Tim , Angus Peter W. , Locarnini Stephen A.
Published: March 2007

Hepatitis B virus (HBV) DNA-transfected hepatoma cells were incubated with the immunosuppressive agents prednisolone, azathioprine, and cyclosporin A (CsA) and the antiviral agents ganciclovir and foscarnet to investigate the effects of these compounds on HBV replication. Prednisolone and azathioprine increased in-tracellular viral DNA and RNA levels approximately twofold and fourfold, respectively. Treatment with CsA did not alter the levels of viral RNA or DNA. A combination of all three immunosuppressive agents increased the level of intracellular viral DNA eightfold, indicating an additive effect. Incubation of the cells in the presence of foscarnet decreased levels of both single-stranded and relaxed circular viral DNA, and in the presence of ganciclovir decreased the levels of relaxed circular viral DNA, predictable effects from their known mechanism of action. The stimulatory effect on viral replication induced by the combination of immunosuppressive agents was substantially inhibited by ganciclovir-foscarnet treatment. These observations could have implications for the management of recurrent HBV infection after liver transplantation. (hepatology 1995 22:36-43.)
Hepatitis B virus infection in high-risk inner-city neighborhoods in San Francisco
Authors: Siegel David , Alter Miriam J. , Morse Stephen
Published: March 2007

To examine the extent of hepatitis B virus infection (HBV) in an inner-city community, we determined the prevalence, incidence, and correlates of HBV seroreactivity in a representative sample of unmarried whites, African-Americans, and Hispanics living in San Francisco during 1988 to 1989 and again 1 year later in 1989 to 1990. Unmarried men and women aged 20 to 44 years were surveyed in a random household sample drawn from three neighborhoods of varying geographic and cultural characteristics. Hepatitis B infection was determined by testing specimens for antibody to hepatitis B core antigen (anti-HBc). Of blood samples available from 1,108 participants from the initial survery, 159 (14%) were anti-HBc positive. There was a strong positive association between anti-HBc positivity and positive serological tests for human immunodeficiency virus, herpes virus type 2, and syphilis. In women and heterosexual men, after controlling for other variables, anti-HBc positivity was significantly associated with older age (P < .001), nonwhite ethnicity (P < .01), less education (P < .05), injection drug use (P < .001), being paid for sex (P < .05), and lifetime number of sexual partners (P < .05). Among homosexually active men, after controlling for other variables, anti-HBc positivity was significantly associated with nonwhite ethnicity (P < .001), injection drug use in a sexual partner (P < .05), and number of lifetime sexual partners (P < .05). There were 19 (3.2%) incident HBV infections. Participants who used injection drugs (relative risk [RR], 8.2; 95% confidence interval [CI] 3.9 to 17.4), crack cocaine (RR, 3.5; 95% CI, 1.2 to 9.6), or who were paid for sex (RR, 7.6; 95% CI, 1.4 to 41.1) were more likely to have recently acquired HBV than participants who did not practice these activities. HBV antibodies were found in 14% of an ethnically diverse community based sample, and in general were associated with serological evidence of and risk behaviors for sexually transmitted diseases as well as with injection drug use. Subjects with incident compared with those with prevalent HBV infections were younger, more commonly heterosexual, and more commonly illicit drug users. (Hepatology 1995 22:44-49).
Proliferative response of CD4+ T cells and hepatitis B virus clearance in chronic hepatitis with or without hepatitis B e-minus hepatitis B virus mutants
Authors: Löhr Hanns F. , Weber Wolfgang , Schlaak Jörg , Goergen Bernd , Zum Büschenfelde Karl-Hermann Meyer , Gerken Guido
Published: March 2007

To assess the significance of cell-mediated immunity, T cells were derived from the peripheral blood and liver tissue of hepatitis B virus (HBV)-infected patients and controls. The analysis of the <3>H-thymidine-uptake in response to a panel of recombinant HBV antigens revealed that peripheral blood mononuclear cells (PBMC) of the 25 viremic patients with inflammatory active, chronic hepatitis B, 16 with wild-type and nine with HBe-minus HBV mutant infection, showed stronger proliferative responses to HBc and HBe antigens than 16 asymptomatic nonviremic HBsAg carriers with normal aminotransferase levels (HBc: SI 19.3 ± 3.9 vs. 13.0 ± 3.2 vs. 8.0 ± 1.2; P < .01 and HBe: SI 16.6 ± 4.0 vs. 10.7 ± 3.5 vs. 6.9 ± 1.5; P < .05). In 15 patients with acute self-limited hepatitis B, however, significantly stronger HBc antigen-specific T-cell responses were observed during HBV clearance and HBe/anti-HBe seroconversion, whereas in nine completely HBV-immunized patients only minor proliferative responses to HBV antigens were observed. Six HBe/HBcAg- and two HBeAg-specific CD4+ T-cell lines could be expanded from liver tissue and peripheral blood of six viremic patients with chronic hepatitis B. Irrespectively of HBV mutations the HBV-specific activation of the T-cell lines was restricted by the presence of HLA-DR molecules and resulted in the release of Th1-like cytokine patterns. Follow-up of interferon (IFN) recipients showed simultaneous short-term increase of HBc/HBe- specific T-cell reactivities in responder patients during HBV clearance and HBe/anti-HBe seroconversion, whereas in nonresponders high virus load and HBV-specific immune responses were in imbalance. In conclusion, HBe/HBc-specific CD4+ helper T cells are related to disease activity. From patients with HBe-minus HBV mutants HBeAg-specific T cells could be obtained in vitro, suggestive of viral escape from the host immune response. We speculate that HBe/HBcAg-specific T helper cells are required to mount an efficient immune response in HBV infection. (Hepatology 1995; 22:61-68.)
Prognostic value of clotting and fibrinolytic systems in a follow-up of 165 liver cirrhotic patients
Authors: Violi Francesco , Ferro Domenico , Basili Stefania , Cimminiello Claudio , Saliola Mirella , Vezza Edoardo , Cordova Corrado
Published: March 2007

One hundred sixty-five patients with cirrhosis diagnosed by needle liver biopsy were followed for 2 years to evaluate the relation between clotting factors and survival. Patients with spontaneous bacterial peritonitis, hepatic carcinoma, and cholestatic liver diseases were excluded. Patients were classified as A (n = 34), B (n = 75), or C (n = 56) according to Child-Pugh criteria. During the follow-up 45 patients died of liver failure or gastrointestinal hemorrhage. Nonsurvivor patients had significantly higher values of bilirubin and D-dimer, a marker of fibrinolysis in vivo, lower values of albumin, prothrombin activity, fibrinogen, prekallikrein, factor VII, and a more prolonged activated partial thrombo-plastin time than survivors. All these variables and Child-Pugh classification were significantly associated with survival in a univariate analysis. Multivariate analysis (Cox's model) showed that only prekallikrein and factor VII were independently predictors of survival. Ninety-three percent of patients with prekallikrein values <32% died within 32 months of follow-up, whereas factor VII <34% identified 93% of patients who died within 10 months of follow-up. This study suggests that factor VII is an early predictor of survival and may be a useful test to better identify cirrhotic patients who should be candidates for liver transplantation. (Hepatology 1995 22: 96-100.)
Effects of bolus injections and continuous infusions of somatostatin and placebo in patients with cirrhosis: A double-blind hemodynamic investigation
Authors: Cirera Isabel , Feu Faust , Luca Angelo , García-Pagan Joan C. , Fernández Mercedes , Escorsell Angels , Bosch Jaime , Rodés Joan
Published: March 2007

The present double-blind study was aimed at investigating the hemodynamic and humoral effects of somatostatin or placebo in patients with cirrhosis. Patients were randomly assigned to receive either an injection of 250 μg of somatostatin followed by a constant infusion of somatostatin at 250 μg/h (n = 13), an injection of 250 μg of somatostatin followed by a 500 μg/h continuous infusion (n = 10), or an injection of placebo followed by a placebo infusion (n = 9). Placebo had no effect. Somatostatin bolus markedly decreased the hepatic venous pressure gradient: by 52% at 1 minute; P < .001; 19% at 3 minutes, P < .01; and by 13% at 5 minutes, P < .04. Azygos blood flow decreased similarly by 45% at 1 minute, P < .001; 16% at 3 minutes, P < .02; and 9.5% at 5 minutes, P = .05. Mean arterial pressure increased by 25% (P < .001). Continuous somatostatin infusions (250 or 500 μg/h) had no systemic effects, but significantly reduced hepatic venous pressure gradient (250 μg/h: −6.1%, P < .05 and 500 μg/h: −15%P < .01) and hepatic blood flow (250 μg/h: −10%, 500 μg/h: −18%, P < .05). Azygos blood flow was not changed after 250 μg/h infusion but was reduced after 500 μg/h (-23%, P < .02). Somatostatin but not placebo; suppressed glucagon to normal levels. This study shows that a bolus injection of somatostatin caused an immediate and marked decrease of hepatic venous pressure gradient and azygos blood flow. Continuous infusion of somatostatin had a mild but sustained effect on splanchnic hemodynamics; this effect was more pronounced with the higher dose. (Hepatology 1995; 22:106-111.)
Clonality in hepatocellular carcinoma: Analysis of methylation pattern of polymorphic X-chromosome-linked phosphoglycerate kinase gene in females
Authors: Kawai Shigenobu , Imazeki Fumio , Yokosuka Osamu , Ohto Masao , Shina Shuichiro , Kato Naoya , Omata Masao
Published: March 2007

Analysis of X-chromosome inactivation patterns in women has been used to assess the clonality of various tumors. In this report, we analyzed 27 liver tumors in women, including 18 samples obtained by the performance of ultrasonically guided thin-needle biopsies. By analysis of the heterogeneity of phosphoglycerate kinase gene, 11 of 27 (41%) cases were found to be heterozygous at the gene. Of these informative 11 cases with liver tumors, 7 cases were “large” tumors (>25 mm in diameter) and 4 cases were “small” tumors (<25 mm in diameter). All 7 large tumors showed monoclonal patterns by the phosphoglycerate kinase gene analysis. Of the 4 small tumors, 2 showed monoclonal, and 2 showed polyclonal patterns. The 2 with monoclonal patterns were pathologically diagnosed as hepatocellular carcinoma despite their small sizes (20 mm and 23 mm). Of the two with polyclonal patterns, the smallest one (15 mm) was diagnosed as benign adenomatous hyperplasia, and the other as hepatocellular carcinoma heavily infiltrated by lymphocytes. These data suggest that analysis of the methylation pattern of the phosphoglycerate kinase gene may be helpful on rare occasions in elucidating the nature of liver tumors but must in fact be used in conjunction with histological appearances to avoid errors secondary to inflammatory infiltrates. (Hepatology 1995; 22:112-117.)
Induction of sensitivity to ganciclovir in human hepatocellular carcinoma cells by adenovirus-mediated gene transfer of herpes simplex virus thymidine kinase
Authors: Qian Cheng , Bilbao Roberto , Bruña Oscar , Prieto Jesús
Published: March 2007

We have analyzed the ability of a recombinant replication-defective adenovirus to transfer the thymidine kinase gene of herpes simplex virus (HSV-tk) into hepatocellular carcinoma (HCC) cells to confer sensitivity to ganciclovir. Three HCC cell lines (Hep3B, PLC/PRF/5, and HepG2) were efficiently infected in vitro by a recombinant adenovirus carrying lacZ reporter gene (Ad-CMVlacZ). Expression of HSV-tk in HCC cells infected with a recombinant adenovirus carrying HSV-tk gene (AdCMVtk) induced sensitivity to ganciclovir in a dosedependent manner. A bystander killing effect was observed when 90% of uninfected tumor cells were mixed with only 10% of AdCMVtk-infected cells. These data show that recombinant adenoviruses are efficient vectors for transduction of drug-sensitizing genes to HCC cells in vitro. We suggest that a gene therapy approach to hepatocellular carcinoma can be established using adenoviral transfer of HSV-tk to tumor cells and subsequent administration of ganciclovir. (Hepatology 1995; 22:118-123.)
Treatment of patients with cirrhosis and refractory ascites using LeVeen shunt with titanium tip: Comparison with therapeutic paracentesis
Authors: Ginès Angels , Planas Ramon , Angeli Paolo , Guarner Carlos , Salerno Francesco , Ginès Pere , Saló Joan , Rodriguez Nivardo , Domènech Eugeni , Soriano Germán , Anibarro Luis , Gassull Miguel Angel , Gatta Angelo , Arroyo Vicente , Rodés Juan
Published: March 2007

It has recently been suggested that insertion of a titanium tip at the venous end of the LeVeen shunt drastically reduces the rate of shunt obstruction. To assess whether the LeVeen shunt with titanium tip improves the results obtained with therapeutic paracentesis, 81 patients with cirrhosis and refractory ascites were randomly assigned to therapy with paracentesis plus intravenous albumin (42 patients) or LeVeen shunt with titanium tip (39 patients). If patients were readmitted for ascites during follow-up, those in the first group were treated with paracentesis, and those in the LeVeen shunt group by the insertion of a new valve or a new shunt if obstruction was demonstrated. During first hospitalization, both treatments were equally effective in removing ascites. Complications were similar in both groups except for a higher rate of severe bacterial infection in the LeVeen shunt group. The mean duration of hospitalization was shorter in the paracentesis group than in the shunt group. During follow-up, the total number of readmissions and the number of readmissions for ascites were higher in the paracentesis group than in the shunt group (252 vs. 99, P < .001; and 193 vs. 43, P < .001, respectively). The total time in hospital, however, was similar (38 ± 38 vs. 39 ± 43 days, P = NS). Three patients had obstruction of the shunt during first hospitalization and 14 patients had a total of 22 obstructions during follow-up. Long-term survival was similar in both groups. The insertion of a titanium tip at the venous end of the LeVeen shunt does not prevent obstruction. The LeVeen shunt with titanium tip does not provide significant improvement over therapeutic paracentesis in the management of cirrhotic patients with refractory ascites. (Hepatology 1995; 22:124-131.)
High plasma levels of atrial natriuretic peptide in preascitic cirrhosis: Indirect evidence of reduced natriuretic effectiveness of the peptide
Authors: Trevisani Franco , Colantoni Alessandra , Sica Giuseppe , Gasbarrini Antonio , D'Intino Paola Emanuela , De Notariis Stefania , De Jaso Rosaria , Barbieri Annarita , Morselli Antonello , Gasbarrini Giovanni , Bernardi Mauro
Published: March 2007

Controversial results come from spot measurements of plasma atrial natriuretic peptide (ANP) in compensated cirrhotic patients. Moreover, either blunted or exaggerated natriuresis has been described after maneuvers increasing plasma ANP. This does not make it possible to delineate the ANP effectiveness. Plasma ANP, renin activity (PRA) and aldosterone and hematocrit were serially measured (7 AM, 9 AM, 6 PM, and 11 PM) in nine preascitic cirrhotic outpatients and in nine healthy subjects on normal sodium diet (150 mmol/day) and carrying on their usual activities (mobile from 7 AM to 10 PM). Daily natriuresis was monitored the day before and during the study. In both groups, ANP peaked at the end of the recumbence period (7 AM) and declined on the assumption of the upright position, so that both ANP values of the standing period were significantly lower than the mean daily level. These fluctuations were reciprocal to PRA and hematocrit changes. Patients showed steadily elevated plasma ANP and reduced PRA (ANP mean daily level: 33.3 ± 3.8 vs. 15.5 ± 3.2 pg/mL, P = .004; PRA: 0.76 ± 0.23 vs. 1.66 ± 0.21 ng/mL/hr, P = .003). Aldosterone fluctuations and mean daily level were similar in the two groups (mean daily level: 122 ± 11 vs. 119 ± 9 pg/mL). Natriuresis was well adapted to the sodium intake and similar in healthy subjects (day 1: 152 ± 11 mmol; day 2: 138 ± 12.5 mmol) and patients (143 ± 15 mmol; 148 ± 29 mmol). Preascitic cirrhotic patients on a normal salt intake and carrying on their usual activities develop a new steady state requiring increased ANP levels to maintain a sodium balance. In addition to a reduced renal sensitivity to ANP, several subtle abnormalities of the antinatriuretic forces may yield the renal hyporesponsiveness to the peptide. (Hepatology 1995; 22:132-137.)
High familial prevalence of gallstones in the first-degree relatives of gallstone patients
Authors: Sarin Shiv K. , Negi Vir S. , Dewan Richa , Sasan Smailaja , Saraya Anoop
Published: March 2007

Limited information is available on the prevalence of gallstones in the first-degree relatives of gallstone patients. Three groups of subjects were studied by realtime ultrasound examination: group A, 105 index gallstone patients (male/female; 20:85); group B, 330 first-degree relatives of index patients; group C, matched controls for group A (n = 105) and group B (n = 330) subjects. Dietary, anthropometric, and biochemical investigations were carried out. In 39 of 105 (37%) index cases, one or more additional family members had gallstones (positive-index case). The positive-index cases were younger than the remaining index cases (mean age, 33.1 ± 14 vs. 44.5 ± 13.1 years; P < .05). Fifty-one of 330 (15.5%) first-degree relatives had gallstones, nearly four and a half times (95% confidence interval [CI], 2.4 to 8.5) more often than in the matched control population (12 of 330 [3.6%]). Thirty-three of 51 (65%) positive relatives were women; mother (37.3%), sister (17.6%) or daughters (10%) to the index patients. There was no difference in the diet, physical activity, and serum lipid profile between the positive index patients and the remaining gallstone patients and positive relatives and their controls. Our results show that there is a strong familial predisposition for gallstone formation. Female relatives of young gallstone patients should be routinely screened for gallstones. (Hepatology 1995;22:138-141.)