bluuebunny/crossref_metadata_2025 huggingface dataset:
In situ nucleic acid hybridization of cytokines in primary biliary cirrhosis: Predominance of the Th1 subset
Authors: Harada K , Van de Water J , Leung P S , Coppel R L , Ansari A , Nakanuma Y , Gershwin M E
Published: July 2004

Primary biliary cirrhosis (PBC) is an autoimmune liver disease characterized by destruction of the intrahepatic bile ducts. It is generally believed that cellular immune mechanisms, particularly involving T cells, result in this bile duct damage. The relative strength of Th1 and Th2 responses has recently been proposed to be an important factor in the pathophysiology of various autoimmune diseases. In this study, we have attempted to identify the Th subset balance in PBC, by detection of cytokines specific to the two T-cell subsets, i.e., interferon γ (IFN-γ) for Th1 cells and interleukin-4 (IL-4) for Th2 cells. We analyzed IFN-γ and IL-4 messenger RNA (mRNA) positive cells in liver sections from 18 patients with PBC and 35 disease controls including chronic active hepatitis C, extrahepatic biliary obstruction (EBO), and normal liver, using nonisotopic in situ hybridization and immunohistochemistry. Mononuclear cells expressing IFN-γ and IL-4 mRNA were aggregated in inflamed portal tracts in PBC livers, but were rarely present in extrahepatic biliary obstruction, alcoholic fibrosis, or normal liver sections. The IFN- γ and IL-4 mRNA positive cells in PBC livers were detected in significantly higher numbers than in control livers (P < .01). Moreover, IFN-γ mRNA expression was more commonly detected than IL-4 expression in PBC livers, and the levels of IFN-γ mRNA expression were highly correlated with the degree of portal inflammatory activity. IFN-γ mRNA-positive cells were detected primarily around damaged bile ducts that were surrounded by lymphoid aggregates. The data indicate that Th1 cells are the more prominent T-cell subset in the lymphoid infiltrates in PBC.
Muscarinic acetylcholine receptor stimulation of biliary epithelial cells and its effect on bile secretion in the isolated perfused liver
Authors: Elsing C , Hubner C , Fitscher B A , Kassner A , Stremmel W
Published: July 2004

The aim was to explore whether biliary epithelial cells show muscarinic acetylcholine receptors and to investigate their role in ductular bile formation. In both, isolated rat biliary epithelial cells and Mz-Cha-1 cells, a biliary epithelial cell line, binding of [3H]N-methyl-scopolamine occurred with 0.718 ± 0.08 and 0.482 ± 0.05 fmol per 10(6) cells, respectively. To characterize the involved second messenger, intracellular Ca2+ levels were monitored by confocal microscopy. Stimulation of biliary epithelial cells with carbachol produced an increase in free cytosolic Ca2+ levels that declined to baseline values describing a sinusoidal oscillation curve. Increasing concentrations of the agonist decreased latency of the response and increased oscillation frequency. Similar results were obtained in Mz-Cha-1 cells. The intracellular Ca2+ originated from IP3 sensitive intracellular stores and from the extracellular medium. The Ca2+ response could partially be blocked by atropine and completely by pirenzepine, a specific muscarinic receptor-type M1 antagonist. The presence of M1 receptor messenger RNA (mRNA) in biliary epithelial cells was confirmed by reverse transcriptase polymerase chain reaction. In the isolated perfused guinea pig liver, a model with high ductular bile flow, carbachol induced a dose dependent decrease of bile flow by 79.6% ± 9.8% at 50 μmol/L carbachol (P < .001), without affecting perfusion pressure or biliary electrolyte concentrations. It is concluded that biliary epithelial cells express muscarinic acetylcholine receptors. Stimulation of this receptor leads to cholestasis. This could be because of changes in peribiliary permeability and/or inhibition of biliary epithelial cell secretory function.
Memantine, a noncompetitive NMDA receptor antagonist improves hyperammonemia-induced encephalopathy and acute hepatic encephalopathy in rats
Authors: Vogels B A , Maas M A , Daalhuisen J , Quack G , Chamuleau R A
Published: July 2004

The aim of this study was to investigate the possible role of N-methyl-D-aspartate (NMDA)-receptor overactivity in two different experimental rat models of encephalopathy: subacute encephalopathy caused by severe hyperammonemia in portacaval-shunted rats (AI-PCS rats) and acute hepatic encephalopathy caused by complete liver ischemia (LIS rats). The effect of the noncompetitive NMDA-receptor antagonist memantine (intraperitoneal [i.p.] 10-20 mg/kg bw or intravenous [i.v.] 5 mg/kg bw) was studied on the severity of encephalopathy by assessment of clinical grading and electroencephalogram (EEG) spectral analysis, on plasma ammonia concentrations, amino acid concentrations in cerebrospinal fluid (CSF), intracranial pressure (ICP), and brain water content. Both rat models developed encephalopathy within 3 to 6 hours, associated with increased CSF glutamate and aspartate concentrations and increased ICP and brain water content. Memantine administration in AI-PCS and LIS rats resulted in a significant improvement in clinical grading and less slowing of EEG activity (P < .05), and smaller increases in CSF glutamate (P < .05) concentrations. Moreover, ICP and brain water content were significantly lower in memantine-treated AI-PCS rats than in untreated AI-PCS rats (P < .05). Memantine had no significant effect on ICP and brain water content in LIS rats, and on ammonia concentrations in both models. These results indicate that NMDA- receptor activation might be involved in the pathogenesis of hyperammonemia-induced encephalopathy and of acute hepatic encephalopathy caused by LIS.
A prospective randomized trial of ceftazidime versus netilmicin plus mezlocillin in the empirical therapy of presumed sepsis in cirrhotic patients
Authors: McCormick P A , Greenslade L , Kibbler C C , Chin J K , Burroughs A K , McIntyre N
Published: July 2004

Aminoglycosides are frequently used to treat sepsis in patients with liver disease. However, it has been suggested that cirrhotic patients are particularly sensitive to aminoglycoside-induced renal dysfunction. We investigated the efficacy and incidence of renal impairment with netilmicin plus mezlocillin compared with ceftazidime in 128 cirrhotic patients who required empirical treatment for sepsis. Renal impairment developed in 8 of 63 (13%) patients receiving netilmicin compared with 2 of 65 (3%) patients receiving ceftazidime (P < .05); it occurred despite regular monitoring of trough netilmicin levels. Renal impairment was present at the time of death in 1 of 13 (8%) patients treated with ceftazidime compared with 5 of 9 (56%) of the netilmicin patients (P < .05). Mortality rates were similar in the two groups (ceftazidime 20%, aminoglycoside 14%; P = NS). Renal dysfunction is significantly more frequent in cirrhotic patients treated with netilmicin but with careful attention to dosage and fluid management the clinical effect is likely to be relatively modest.
Gap junctions and growth control in liver regeneration and in isolated rat hepatocytes
Authors: Fladmark K E , Gjertsen B T , Molven A , Mellgren G , Vintermyr O K , Døskeland S O
Published: July 2004

The hepatocytes in the mature normal liver are tightly coupled through gap junctions, except during compensatory hyperplasia (regeneration) after partial hepatectomy when the gap junctions become down-regulated. The significance of this down-regulation has been a long-standing enigma. The present study of hepatocytes in primary culture and in the regenerating liver aimed at defining the relationship, if any, between hepatocyte gap junctional communication and proliferation. Gap junctional down-regulation in the regenerating liver appeared to be a specific phenomenon because desmosomes and the surface contact area between neighboring hepatocytes remained constant. All agents and conditions (dexamethasone in vivo; dexamethasone, cyclic adenosine monophosphate, serum, and high cell density in vitro) delaying gap junctional down-regulation also increased the lag before the cells reached competence to enter S phase. This raised the possibility that hepatocyte DNA replication was inhibited through preservation of gap junctions. However, we disproved this assumption by showing that the DNA replication (more specifically the G1/S transition rate constant) was inhibited even in hepatocytes completely devoid of gap junctional communication. The teleological advantage of linking gap junctional down-regulation to hepatocyte G1 progression therefore may not be to trigger DNA replication but to ensure that proliferating hepatocytes and hepatocytes responsible for liver-specific metabolic functions maintain separate pools of metabolites and signaling molecules.
Hepatocarcinogenesis in woodchuck hepatitis virus/c- myc mice: Sustained cell proliferation and biphasic activation of insulin-like growth factor II
Authors: Liu P , Terradillos O , Renard C A , Feldmann G , Buendia M A , Bernuau D
Published: July 2004

Transgenic mice carrying the c-myc oncogene under control of woodchuck hepatitis virus (WHV) DNA sequences invariably develop hepatocellular carcinoma (HCC), despite a temporally limited expression of the transgene in the neonatal liver. To better characterize the different steps of the tumorigenic process, we analyzed the liver expression of the c-myc transgene and several growth-related genes by in situ hybridization and Northern blotting. In parallel studies, proliferated changes were investigated by detection of bromodeoxy-uridine-positive S-phase nuclei and apoptosis was evaluated by in situ nick end-labeling of DNA. During the neonatal period, high levels of c-myc messenger RNAs (mRNAs) were detected in all hepatocytes, and the expression of insulin-like growth factor II (IGF II) was frequently enhanced, correlating with increased cell proliferation. Despite elevated expression of the p53 gene, no change in liver cell apoptosis was observed. After weaning, c-myc transgene expression decreased to undetectable levels in all hepatocytes, whereas proliferation decreased but remained notably higher than in age-matched controls. The expression of c-fos, c-jun, and c-H-ras was highly variable during the preneoplastic period and in the tumors, with no consistent increase compared with controls. Resurgence of c-myc transgene expression was evidenced in all cells from hyperplastic lesions and carcinomas, accompanied with frequent focal reactivation of IGF II. Thus the strong proliferative stimulus induced by the combined effects of c-myc and IGF II in the neonatal liver might initiate a process characterized by persistent, dysregulated hepatocyte proliferation, in turn greatly increasing the risk of hepatocellular transformation.
Rat hepatocytes isolated from alcohol-induced fatty liver have an increased sensitivity to anoxic injury
Authors: Caraceni P , Ryu H S , Subbotin V , De Maria N , Colantoni A , Roberts L , Trevisani F , Bernardi M , Van Thiel D H
Published: July 2004

The aim of this study was to determine whether rat hepatocytes isolated from steatotic or nonsteatotic livers have different thresholds for injury due to anoxia-reoxygenation. Rats were fed ethanol or control diets for 8 weeks. Histology showed that more than 75% of the hepatocytes in alcohol-fed and less than 3% in control animals contained fatty vacuoles. The glycogen content was significantly reduced in steatotic livers. Isolated hepatocytes were cast in agarose gel threads and perfused with Krebs-Henseleit bicarbonate buffer. Cell viability was determined by Trypan Blue (TB) exclusion; cell injury was determined by lactate dehydrogenase (LDH) release; and superoxide anion (O2
·−) was determined by lucigenin-enhanced chemiluminescence (LCL). During the pre-anoxic basal perfusion the following occurred: viability was 86% ± 1% and 85% ± 1%; LDH release was 16 ± 3 and 15 ± 3 mU/min; and LCL was 4 ± 1 and 5 ± 1 nA in steatotic and nonsteatotic hepatocytes, respectively. Cell viability decreased slightly under 4 hours of aerobic perfusion without differences between the two groups. In contrast, fatty hepatocytes died much faster than did control hepatocytes during anoxia; after 3 hours viability was 17% ± 8% vs. 60% ± 2% (P < .001), respectively. With reoxygenation following 2 hours of anoxia, the changes in viability, in LDH release, and in LCL were similar in both groups. These results indicate that in hepatocytes isolated from alcohol-fed rats when compared with control hepatocytes: (1) cell viability under aerobic conditions is not influenced; (2) anoxic injury is significantly increased; (3) a reduction in the hepatic glycogen stores, which may contribute to the enhanced sensitivity to anoxia, can be demonstrated; and (4) O2
·− generation and cell injury occurring immediately after reoxygenation do not appear to be affected.
Disruption of actin organization by cytochalasin D does not impair biliary secretion of organic anions in the rat
Authors: St-Pierre M V , Dufour J , Arias I M
Published: July 2004

The bile canaliculi of hepatocytes contract spontaneously, and it is hypothesized that this canalicular motility provides a propulsive force for normal intrahepatic bile flow. Cytochalasin disrupts actin polymerization, inhibits contraction, and decreases bile flow. We investigated whether this cholestasis was associated with impaired canalicular secretion. Isolated rat hepatocyte doublets, with and without incubation with 2 mumol/L cytochalasin D (cytD), were superfused, under first-order conditions, to steady state with fluorescein isothiocyanate-labeled glycocholic acid (FITC-GC) and carboxy-4′,5′-dimethylfluorescein diacetate (CMFD), which are fluorescent substrates for the bile acid and the nonbile acid organic anion transport pathways, respectively. Fluorescent microscopic images were quantified and the data analyzed by noncompartmental and compartmental kinetic methods. cytD dilated the canalicular spaces fivefold but did not change the proportion of doublets that secreted either probe. Cytochalasin did not affect the mean cellular transit times of FITC-GC (2.8 and 2.5 minutes for control and cytochalasin-treated groups, respectively) and of carboxy-4′,5′-dimethylfluorescein (3.8 and 3.7 minutes, respectively). Analysis with a three-compartment model gave estimates of the rate constants for canalicular secretion: 0.21 ± 0.04 and 0.22 ± 0.03 min−1 in control and treated cells, respectively, for FITC-GC, and 0.14 ± 0.01 and 0.16 ± 0.02 min−1, respectively, for carboxy-dimethylfluorescein. When kinetics are first-order, the canalicular secretion of organic anions is not altered by actin disruptive agents, suggesting that actin filaments do not modulate the function or distribution of these transporters. This suggests that impaired contractility rather than impaired canalicular secretion is the mechanism of cytD-induced cholestasis.
The Child-Pugh classification as a prognostic indicator for survival in primary sclerosing cholangitis
Authors: Shetty K , Rybicki L , Carey W D
Published: July 2004

Clinical decisions in primary sclerosing cholangitis (PSC) depend upon understanding its variable natural history. Several prognostic models for survival have been developed. We explored the Child-Pugh Classification (CPC) to determine if it predicts survival as well as a disease-specific model (DSM). We identified 208 PSC patients who satisfied established criteria. Prognostic variables were measured from the first visit. Kaplan-Meier survival estimates were obtained for CPC twice, once censoring observations at orthotopic liver transplantation and again considering orthotopic liver transplantation as a failure. A stepwise Cox proportional hazards-model was used to identify the factors associated with mortality. For 208 patients, the mean follow-up was 70 months (SD + 55). Kaplan-Meier 7-year survivals for CPC A, B, and C were 89.8%, 68%, and 24.9%, respectively (P < .001). The Cox model identified CPC and age as the most significant predictors of mortality. Adding the DSM risk score did not significantly improve the fit of the model (P = .75). The following were concluded: 1) CPC is a powerful predictor of survival in PSC; 2) DSM does not enhance the predictive ability of CPC; and 3) CPC may be used as an alternative to the DSM in research studies and clinical decision-making.
Clonotypic analysis of T cells in patients with autoimmune and viral hepatitis
Authors: Tanaka A , Iwabuchi S , Takatori M , Ohno A , Yamada H , Hashimoto N , Ikeda Y , Kato T , Nishioka K , Iino S , Yamamoto K
Published: July 2004

The immunopathogenesis of autoimmune hepatitis (AIH), and the role of T cells in the onset and maintenance of this disease, are still unclear. Since T cells expand clonally after stimulation by an antigen, it is important to analyze the behavior of T cells at a clonal level. We have established recently a novel system, using reverse transcriptase-polymerase chain reaction (RT-PCR) and subsequent single-strand conformation polymorphism (SSCP) that allows the identification of clonal accumulation of T cells in a lymphocyte population. Using this system, we demonstrated that oligoclonal T cells were accumulated in the liver of patients with AIH, and that identical T-cell clonotypes were detected in two different regions of the liver, although these features were also observed in cases with viral hepatitis. Only in cases with AIH, however, nearly all identical T cells were found to belong to CD8+ subset and there were very few CD4+ T cells in this population. Our results suggest that common antigens presented to CD8+ T cells in the context of HLA class I molecule are distributed diffusely in the liver of AIH. These findings also suggest that antigens recognized by CD4+ T cells may be relatively heterogeneous in the liver with AIH.
Decreased natural killer cytotoxic activity in chronic alcoholism is associated with alcohol liver disease but not active ethanol consumption
Authors: Laso F J , Madruga J I , Giron J A , Lopez A , Ciudad J , San Miguel J F , Alvarez-Mon M , Orfao A
Published: July 2004

Chronic alcohol intake is associated with an increased incidence of certain neoplasms. Natural killer (NK) cells have been considered to be involved in control tumor development and growth. The goal of the present study was to contribute to a better understanding of the effects of ethanol (EtOH) per se on the NK-cell population. Both patients with chronic alcoholism without liver disease (AWLD) and subjects with alcohol-induced cirrhosis (ALC) were carefully selected for this study. Immunophenotypical and functional studies of peripheral blood (PB) NK-cells were performed during active EtOH intake and after 3 months of a withdrawal period. In the AWLD group a significant increase in number of NK-cells (CD3-/CD56+) (P < .05) associated with a parallel increase in NK-cell lytic activity (P < .01) was observed. In addition, the number of cytotoxic T cells displaying the CD3+/CD56+ phenotype as well as CD8-/CD57+ NK-cell subset was also increased (P < .01 and P < .001, respectively). By contrast, in ALC patients with active EtOH intake (ALCET group), although a significant increase in the number of NK PB lymphocytes was observed (P < .05), NK lytic activity was depressed (P < .05), suggesting the existence of a decreased lytic activity/NK-cell. After 3 months of EtOH withdrawal, PB mononuclear cells (PBMC) from the AWLD group patients still displayed an increased NK cytolytic activity; in addition, the number of PB NK-cells (CD3-/CD56+ and CD8-/CD57+) and CD3+/CD56+ PB T cells continued to be increased. Independently of the duration of withdrawal period, in ALC patients EtOH withdrawal was followed by a slight decrease in the NK lytic activity of PBMC with respect to the values in active alcoholism phase; slight differences observed in the NK lytic activity in ALC patients who quit drinking could be related to the tendency to decrease of the number of NK-cells toward normal values. Furthermore, although an increase in NK cytotoxic activity after stimulation of PBMC with interleukin-2 (IL-2) was observed in ALC, it did not reach the levels observed in healthy subjects. Overall, our results show that the behavior of PB NK-cell population in chronic alcoholism is different according to both the moment of EtOH consumption and the existence or not of ALC. Alcohol by itself induced an increase in the number and lytic activity of NK-cells. By contrast, the NK cytolytic activity is constantly depressed in the stage of alcoholic cirrhosis, supporting the notion that immunosurveillance mechanisms may be affected in these patients.
Pretreatment with activated protein C or active human urinary thrombomodulin attenuates the production of cytokine-induced neutrophil chemoattractant following ischemia/reperfusion in rat liver
Authors: Yamaguchi Y , Hisama N , Okajima K , Uchiba M , Murakami K , Takahashi Y , Yamada S , Mori K , Ogawa M
Published: July 2004

We investigated the role of anticoagulant in the ischemia/reperfusion injury of the liver, using activated protein C (APC), active human urinary thrombomodulin (UTM), and factor Xa blocked at the active site (DEGR-Xa). Liver ischemia was induced in male Wistar rats by occlusion of the portal vein with a microvascular clip for 30 minutes. Each anticoagulant was injected intravenously 10 minutes before clamping the portal vein. Serum concentrations of cytokine-induced neutrophil chemoattractant (CINC) were determined by enzyme-linked immunosorbent assay. The serum levels of CINC increased significantly following reperfusion, reaching a peak in 6 hours, and then decreasing gradually to control levels by 24 hours. CINC levels in rats pretreated with APC (500 U/kg), UTM (3,000 TMU/kg), or DEGR-Xa (10 mg/kg) peaked 3 hours following reperfusion and decreased rapidly to baseline level within 6 and 12 hours, respectively. These peak values were significantly lower than those observed in untreated rats (P < .01). Expression of CINC transcripts in liver tissue of untreated rats was evaluated by Northern blot analysis and peaked 3 hours following reperfusion. Pretreatment with these anticoagulants significantly decreased the expression of CINC messenger RNA transcripts as compared with untreated animals. Myeloperoxidase activity and the number of neutrophils accumulated into the liver 24 hours following ischemia/reperfusion were also significantly decreased in animals pretreated with these anticoagulants. In addition, correlations between the peak values of liver enzymes and serum CINC levels were found to be significant (P < .001). The inactive derivative of factor Xa, a selective inhibitor of thrombin generation, inhibited ischemia/reperfusion-induced increases in the serum concentration and messenger RNA transcript quantities of CINC. The inactive factor Xa also reduced hepatic accumulation of neutrophils after ischemia/reperfusion. These results indicate that the release of CINC is likely related to the hepatic microcirculation disturbance induced by microthrombotic occlusion following ischemia/reperfusion.
The expression of endosomal rab proteins correlates with endocytic rate in rat liver cells
Authors: Juvet L K , Berg T , Gjoen T
Published: July 2004

Hepatic endocytosis is characterized by a division of labor between the different cell types with respect to endocytosis, which is mediated by receptors expressed on their cell surface. We have investigated the expression of GTPases of the rab family in rat liver parenchymal and endothelial cells. Small GTPases of the rab protein family control distinct steps of intracellular transport both in the secretory and the endocytic pathway. As controls have been employed the normal rat kidney (NRK) cell line and brain tissue, neuronal cells are known to express high levels of components of the endocytic machinery (clathrin, adaptins, dynamin, uncoating adenosine triphosphatase, etc.). Endothelial cells were found to express four to seven times more rab4, rab5, and rab7 than parenchymal cells. A similar relationship was found between the endocytic rates in the two cell types; the rate of internalization from the plasma membrane of mannose receptors in rat liver endothelial cells was 2.3 pools/min, whereas the corresponding value for internalization of the galactose receptor in parenchymal liver cell was 0.27 pools/min (comparable with the rate of transferrin internalization in NRK cells). Both immunofluorescence and subcellular fractionation experiments showed that rab5 and rab7 were associated with compartments along the endocytic pathway. Brain tissue showed a similar high expression of endocytic components (rab4, rab5, and rab7) as liver endothelial cells, whereas lower values were found in NRK cells. We also analyzed the following proteins involved in endocytosis: clathrin, α-adaptin, β-adaptin, and rabaptin-5. These proteins showed the same pattern of expression as the rab proteins. In conclusion, the results obtained with liver cells corroborate the data obtained in transfected cells and support the notion that rab proteins may be involved in controlling the endocytic rate in liver cells.
Resolution of gas exchange abnormalities and intrapulmonary shunting following liver transplantation
Authors: Battaglia S E , Pretto J J , Irving L B , Jones R M , Angus P W
Published: July 2004

This prospective study evaluated pulmonary gas exchange in patients with severe liver disease, its relationship to intrapulmonary shunting, and its response to liver transplantation. Detailed clinical examinations, chest radiographs, and arterial blood gas estimations were performed on 74 consecutive patients before and after liver transplantation. Fifty percent of the 74 patients had a widened alveolar-arterial (A-a) oxygen gradient (> 15 mm Hg) and 45% a reduced PaCO2 (< 35 mm Hg). Twenty-two percent were hypoxemic (PaO2 < 80 mm Hg). Following transplantation mean PaO2 increased (pre-89 ± 14 vs. post-94 ± 8 mm Hg; P = .014) and A-a oxygen gradient decreased (pre- 16 ± 14 vs. post-8 ± 9 mm Hg; P < .001), despite an increase in PaCO2 (pre-36 ± 5 vs. post-39 ± 4; P < .001). To examine this improvement in oxygen exchange further, a subgroup of 26 consecutive patients, with no obvious cardiorespiratory cause for abnormal gas exchange underwent, pre- and post-operative spirometry, measurement of carbon monoxide diffusion capacity (DLCO), intrapulmonary shunt estimations (100% oxygen technique), and echocardiography. In this subgroup, 23% were hypoxemic, 54% had a widened A-a oxygen gradient, and 85% had increased intrapulmonary shunting (> 5%) before transplantation. There was a significant correlation between the degree of pre-transplantation intrapulmonary shunting and A-a oxygen gradient (P < .01). Nineteen of the 22 patients with increased shunting improved following transplantation and improved A-a oxygen gradient correlated well with the reduction in shunting (P < .005). DLCO was reduced in 69% of these patients with a mean value of 73% of predicted. However, the post-transplantation mean DLCO did not increase despite the improvement in oxygen exchange. In conclusion, gas exchange abnormalities are common in patients with severe liver disease but these usually resolve post-transplantation. Intrapulmonary shunting is a major determinant of abnormal oxygen uptake in transplant candidates without evidence of cardiorespiratory disease. Finally, the mechanism for the reduced DLCO is unclear but appears different to that responsible for intrapulmonary shunting and abnormal oxygen exchange.
Peripheral blood chimerism following human liver transplantation
Authors: Jonsson J R , Hogan P G , Thomas R , Steadman C , Clouston A D , Balderson G A , Lynch S V , Strong R W , Powell E E
Published: July 2004

The aim of this study was to prospectively investigate the peak levels and kinetics of donor leucocyte chimerism in human recipients following liver transplantation. The peak levels of chimerism were observed within the first 48 hours following transplantation and ranged from 0.15% to 20% of total peripheral blood mononuclear cells. In all but one patient, who developed graft versus host disease, there was an early peak level of chimerism that declined over time such that donor leukocytes were only intermittently detectable after 3 to 4 weeks. In 8 patients who had no episodes of graft rejection, the peak level of donor leukocyte chimerism ranged from 1.3% to 20% (mean ± SEM; 5.5% ± 2.1%). In 3 patients who were treated for episodes of acute graft rejection during the first four postoperative weeks, the peak level of donor leukocyte chimerism ranged from 0.15% to 0.2% (0.18 ± 0.02, P = .012). The results demonstrate a marked variation in the total number of donor leukocytes detectable in the peripheral blood early after liver transplantation and also, that lower levels of chimerism may be associated with lower rates of initial graft acceptance and a higher incidence of acute rejection.
Early antibody response against hypervariable region 1 is associated with acute self-limiting infections of hepatitis C virus
Authors: Zibert A , Meisel H , Kraas W , Schulz A , Jung G , Roggendorf M
Published: July 2004

Antibodies directed to hypervariable region 1 (HVR1) of hepatitis C virus (HCV) have recently been shown to neutralize the corresponding HCV isolate in vitro. We analyzed the appearance of antibodies directed to HVR1 during the course of infection in a large group of patients who have been infected by the same isolate of a HCV contaminated anti-D immunoglobulin (HCV-AD78). An enzyme-linked immunosorbent assay (ELISA) was established using a synthetic peptide to detect antibodies against the main HVR1 variant of HCV-AD78. 207 sera obtained at different time points post infection (p.i.) of 51 patients having either acute self- limiting (n = 28) or chronic infection (n = 23) were studied. Antibodies directed to HVR1 were found at least at one time point during the infection course in 15 of 28 patients (53%) having acute self-limiting infections and in 17 of 23 patients (74%) with chronic disease. The time of appearance of anti-HVR1 was significantly different between these two patient groups (P < .025) although appearance and titers of other HCV-specific antibodies were found to be similar at early time points p.i. In acute self-limiting infections 9 of 21 sera (43%) of respective patients with sera available within the first 6 months p.i. were anti-HVR1 positive. The highest prevalence of anti-HVR1 in this group of patients was within month 6 to 12 p.i. (64%). None of the sera available after 24 months p.i. had such antibodies. In contrast, only 2 of 15 sera (13%) of chronically infected patients with respective time points of sera were anti-HVR1 positive within the first 6 months p.i. and only 5 of 18 sera (28%) were positive within month 7 to 12 p.i. Seven patients with chronic HCV infections showed at least two consecutive anti-HVR1 negative early time points up to month 18 p.i. Prevalence of anti-HVR1 after 24 months p.i. was high (84%) in this group of patients and most of the patients maintained high levels of anti-HVR1 for up to 17 years p.i. Our findings suggest clearance of virus by respective neutralizing antibodies resulting in a self-limiting infection and may have implications for prognosis of the disease and also for any future vaccine development.
Hepatitis C virus genome complexity correlates with response to interferon therapy: A study in French patients with chronic hepatitis C
Authors: Le Guen B , Squadrito G , Nalpas B , Berthelot P , Pol S , Brechot C
Published: July 2004

Recent studies performed in Japan have suggested that hepatitis C virus (HCV) genome heterogeneity might be taken as a predictive virological parameter of response to interferon alfa (IFN-α) treatment. However, there is presently no information on the impact of this virological parameter in patients from Western countries infected by different HCV genotypes. We have investigated this issue by using amplification of HCV E2 hypervariable region 1, followed by single-strand conformation polymorphism assay (PCR-SSCP). We have studied 95 French patients infected with various genotypes and treated with IFN-α-2b. We analyzed the impact of the following parameters by univariate and multivariate analyses: HCV heterogeneity, HCV genotype, viral load, and liver histology in response to therapy. Age > 40 years (P < .01), viral load > 35 × 105 Eq/mL (P < .01), genotype 1 (P < .01), and a number of SSCP bands > 3 (P < .001) were significantly associated with nonresponse or relapse; cirrhosis was associated with nonresponse. In multivariate analysis, three variables were independently associated with the absence of long-term response: SSCP bands > 3, genotype 1, and viral load > 35 × 105 with odds ratios of 19, 7.5, and 11.8, respectively. Our data establish the major importance of HCV genome heterogeneity in patients infected with both HCV types associated with low (genotype 1b) or high (genotype 3a) response to IFN-α.
Association of seropositivity for hepatitis viruses and aplastic anemia in Thailand
Authors: Issaragrisil S , Kaufman D , Thongput A , Chansung K , Thamprasit T , Piankijagum A , Anderson T , Shapiro S , Leaverton P , Young N S
Published: July 2004

Aplastic anemia is more common in the Orient than in western countries, with an incidence in Thailand that is 2- to 3-fold higher than in Europe. Aplastic anemia after hepatitis is a well characterized clinical entity, and clinical hepatitis is also prevalent in the Far East. We performed a prospective case-control study to determine risk factors for aplastic anemia in Bangkok and two rural regions during 1989 to 1994. A total of 375 cases were identified, along with 1,174 hospital controls matched for age and sex. Historical data were collected by trained interviewers. Sera from a subset of cases (N = 177) and controls (N = 183) were tested for antibodies to hepatitis viruses A, B, and C and hepatitis B surface antigen. There was no evidence of association of aplastic anemia with hepatitis B or hepatitis C. Previous exposure to hepatitis A, as determined by immunoglobulin G (IgG) seropositivity, was significantly associated with aplastic anemia: the relative risk adjusted for confounding was 2.9 (95% confidence interval 1.2-6.7). The same association also existed for persons under age 25 years, in whom the prevalence of hepatitis A IgG was lower than in the total population. However, no patients showed evidence of recent infection with hepatitis A (immunoglobulin M [IgM] seropositivity). These results indicate that exposure to a hepatitis virus is a risk indicator for aplastic anemia in Thailand, and while itself unlikely to be etiologic, hepatitis A may be a surrogate marker for another enteric microbial agent.
Detection of GBV-C RNA in patients with non-A-E fulminant hepatitis by reverse-transcription polymerase chain reaction
Authors: Kanda T , Yokosuka O , Ehata T , Maru Y , Imazeki F , Saisho H , Shiratori Y , Omata M
Published: July 2004

GBV-C might be a causative agent of fulminant hepatitis of unknown etiology. Fulminant hepatitis is an indication for liver transplantation. However, in Japan, because of the legal difficulties associated with cadaveric donation, patients with fulminant hepatitis are still treated by plasmapheresis and multiple transfusions of fresh frozen plasma. So, the possibility that GBV-C might be transmitted by transfusions after the onset of fulminant hepatitis is real. Therefore, we have examined the possible role of GBV-C in non-A-E fulminant hepatitis. Nine patients with non-A-E fulminant hepatitis and one with non-A-E late onset hepatic failure were examined. Sera were obtained from the patients at admission before any blood or blood products were given, and again after transfusions. GBV-C RNA was detected by nested reverse transcription polymerase chain reaction with primers based on the reported sequence. GBV-C RNA was negative in all 10 pretransfusion patients with non-A-E fulminant hepatitis or late onset hepatic failure. Then, fresh frozen plasma was transfused to these patients, and four of them became seropositive. GBV-C is unlikely to be a major etiologic agent for non-A-E fulminant hepatitis in Japan.
Hepatitis G virus in patients with cryptogenic liver disease undergoing liver transplantation
Authors: Pessoa M G , Terrault N A , Ferrell L D , Kim J P , Kolberg J , Detmer J , Collins M L , Yun A J , Viele M , Lake J R , Roberts J P , Ascher N L , Wright T L
Published: July 2004

To examine the prevalence of hepatitis G virus (HGV) in end-stage liver disease of unknown cause and the role of HGV infection in posttransplantation hepatitis, we studied 46 patients undergoing liver transplantation (mean age, 50 years; M: F, 18:28) with cryptogenic cirrhosis. HGV RNA was detected by polymerase chain reaction (PCR) and was quantified by a branched DNA (bDNA) assay. The prevalence of HGV RNA was determined in samples collected before and after liver transplantation and was found to be 22% and 67%, respectively. We evaluated the prevalence of posttransplantation hepatitis in 25 patients, 16 of whom were HGV-positive and 9 were HGV-negative. The proportion of patients with hepatitis was not significantly different in the two groups (38% in HGV-positive and 22% in HGV-negative patients). The median histological scores were significantly higher in liver biopsies from patients with HGV infection than in those without HGV infection (2 [range, 0-14] and 1 [range, 0-3]; P = .01), but the histological scores were low overall. The duration of follow-up was similar in the two groups. HGV RNA levels were not correlated with the severity of liver disease based on histological score (r = −.08). Graft survival and patient survival were not significantly different. We concluded that liver disease was frequent (32%) after transplantation in patients with a pretransplantation diagnosis of cryptogenic cirrhosis, although the disease was generally mild. Although HGV RNA was demonstrable in the majority (67%) of patients after transplantation, there was no relationship between the presence of HGV RNA and the presence of posttransplantation liver disease. The finding of posttransplantation hepatitis in the absence of known viruses (A-G), suggests that other, as-yet-unidentified viruses may be important.
Influence of malnutrition on the prevalence of bacterial translocation and spontaneous bacterial peritonitis in experimental cirrhosis in rats
Authors: Casafont F , Sanchez E , Martin L , Aguero J , Romero F P
Published: July 2004

Bacterial translocation (BT) has been involved in the pathogenesis of spontaneous bacterial peritonitis (SBP) in experimental cirrhosis. Because malnutrition is a common feature in cirrhosis, the aim of this study was to evaluate the effect of nutrition on BT and SBP. We induced cirrhosis in 44 Sprague-Dawley rats by administration of oral CCl4, and, afterward, 26 animals were maintained with dietary restriction. Cultures of mesenteric lymph nodes (MLN), peripheral and portal blood, liver, and spleen were performed. SBP occurred in 48% of the rats with ascites, this being more frequent in the malnourished animals (80%) than in control rats (29%). BT appeared in all the rats with SBP (100%) but only in 57% without it. In the malnourished animals, the BT rate was 95%, while it was 30% in the control group. These results suggest that malnutrition increases the BT rate and the risk of developing SBP in experimental cirrhosis, and that BT is frequent in cirrhosis and may play a role in the development of SBP.
Target platelet antigens of autoantibodies in patients with primary biliary cirrhosis
Authors: Feistauer S M , Penner E , Mayr W R , Panzer S
Published: July 2004

Primary biliary cirrhosis (PBC) is an autoimmune disease of the liver, frequently associated with thrombocytopenia. As various immune abnormalities have been described in PBC, we hypothesized that thrombocytopenia is also an autoimmune phenomenon in these patients. We therefore assessed the frequency of platelet antibodies and their target platelet glycoprotein (GP) specificities. We investigated 66 PBC patients with a median disease duration of 25 months. Twenty-two patients with alcoholic liver disease and thrombocytopenia served as controls. Specificities of platelet antibodies were determined by the monoclonal antibody-specific immobilization of platelet antigens (MAIPA) assay using monoclonal antibodies directed against GPIIb/IIIa and GPIb/IX. The notion that immunoglobulins are nonspecifically bound to platelets was further evaluated by the production of eluates from antibody-coated platelets. The specificities of antibodies in these eluates were again determined by the MAIPA assay. Twenty-six PBC patients had platelet antibodies, whereas antibodies were not detectable in control alcoholic patients. Seven of 13 thrombocytopenic PBC patients had detectable antibodies. Overall, GP Ib/IX and GP IIb/IIIa served in a similar frequency as target antigens. Antibody specificities were confirmed by the production of eluates from platelets. These studies provide evidence that antibodies are specifically bound to platelets in patients with PBC and that the development of immune phenomena in PBC may also involve immuno-mediated platelet destruction.
Endoscopic variceal ligation in prophylaxis of first variceal bleeding in cirrhotic patients with high-risk esophageal varices
Authors: Lay C , Tsai Y , Teg C Y , Shyu W S , Guo W S , Wu K L , Lo K J
Published: July 2004

To determine the efficacy of endoscopic variceal ligation (EVL) in prophylaxis on the rate of first esophageal variceal bleeding, we conducted a prospective, randomized trial in 126 cirrhotic patients with no history of previous upper gastrointestinal bleeding and with esophageal varices endoscopically judged to be at high risk of hemorrhage. The end-points of the study were bleeding and death. Life-table curves showed that prophylactic EVL significantly diminished the rate of variceal hemorrhage (12/62 [19%] vs. 38/64 [60%]; P = .0001) and overall mortality (17/62 [28%] vs. 37/64 [58%]; P = .0011). The 2-year cumulative bleeding rate was 19% (12/ 62) in the EVL group and 60% (38/64) in the control group. The 2-year cumulative mortality rate was 28% (17/62) in the EVL group and 58% (37/64) in the control group. Comparison of Kaplan-Meier estimates of the time to death of both groups showed significantly lower mortality in the ligation group (P = .001). Patients undergoing EVL had few treatment failures and died mainly of hepatic failure. The lower risk in the EVL group was attributed to a rapid reduction of variceal size. Prophylactic EVL was more efficient in preventing first bleeding in patients with good condition (Child A) than in those with decompensated disease (Child B and C). We conclude that prophylactic EVL can decrease the incidence of first variceal bleeding and death over a period of 2 years in cirrhotic patients with high-risk esophageal varices.
Assessment of the role of activin A and transforming growth factor β in the regulation of AML12 cell growth
Authors: Zhang Y , Mashima H , Kanzaki M , Shibata H , Kojima I
Published: July 2004

The present study was conducted to determine the role of two autocrine factors, activin A and transforming growth factor β (TGF-β), in the growth regulation of AML12 hepatocytes. We overexpressed truncated type II activin and/or TGF-β receptors in AML12 cells. In AML12 cells overexpressing truncated type II activin receptors (AML-tAR cells), the inhibitory effect of activin A on DNA synthesis was completely blocked. AML-tAR cells proliferated faster than parental cells, both in the presence and absence of epidermal growth factor (EGF). However, AML-tAR cells could not grow in soft agar. Follistatin augmented EGF-induced DNA synthesis in AML12 cells, whereas it was ineffective in AML-tAR cells. In AML12 cells overexpressing truncated type II TGF-β receptor (AML-tTR cells), the inhibitory effect of TGF-β on DNA synthesis was blocked. AML-tTR cells proliferated faster than parental cells, both in the presence and absence of EGF, but at a slower rate than that of AML-tAR cells. AML-tTR cells did not grow in soft agar. The growth rate of cells overexpressing both types of truncated receptors was identical to that of AML-tAR cells, and these cells did not grow in soft agar. These results indicate that both activin A and TGF-β act as autocrine inhibitors of DNA synthesis in AML12 cells, and that the blocking of the actions of two factors does not lead to transformation. Activin A is a predominant autocrine factor in these cells.
Production and role of interleukin-10 in concanavalin A-induced hepatitis in mice
Authors: Louis H , Le Moine O , Peny M , Quertinmont E , Fokan D , Goldman M , Deviere J
Published: July 2004

Experimental T-cell-mediated hepatitis induced by concanavalin A (Con A) involves the production of proinflammatory cytokines. Because interleukin (IL)-10 is a potent anti-inflammatory cytokine derived from macrophages and T cells and is produced within the liver, we investigated the role of IL-10 in modulating the hepatotoxicity and the secretion of cytokines following in vivo injection of Con A. IL-10 is produced early in the serum after Con A challenge. Neutralization of endogenous IL-10 by monoclonal antibodies (mAbs) increases the secretion of tumor necrosis factor α (TNF-α) (+111%), interferon gamma (IFN-γ) (+92%), and IL-12 (+730%) 8 hours after Con A injection, and increases the hepatotoxicity, assessed by serum alanine transaminase (ALT) (+174%) measurement and by histology, 24 hours after induction of hepatitis. Conversely, preadministration of recombinant IL-10 reduces the production of these proinflammatory cytokines (-47%, -80%, and -47% for TNF-α, IL-12, and IFN-γ, respectively), and decreases neutrophil infiltration and ALT serum concentration (-74%) 8 hours after Con A challenge. We conclude that IL-10, either endogenously produced or exogenously added, has a hepatoprotective role in Con A-induced hepatitis, through its suppressive property on proinflammatory cytokine production, and that it might be of therapeutic relevance in human liver diseases involving activated T cells.
Effects of the Japanese herbal medicine “Sho-Saiko-To” (TJ-9) on in vitro interleukin-10 production by peripheral blood mononuclear cells of patients with chronic hepatitis C
Authors: Yamashiki M , Nishimura A , Suzuki H , Sakaguchi S , Kosaka Y
Published: July 2004

“Sho-saiko-to” (TJ-9) consists of 7 herbal components. In Japan, it is widely prescribed to patients with chronic viral liver disease. TJ-9 is known to suppress liver cancer development and possess macrobiotic effects, but its mode of action is not fully understood. This study investigated the following: (1) cytokine production levels, mainly interleukin (IL)-10, in peripheral blood mononuclear cells of chronic active hepatitis B and C patients, and healthy volunteers; (2) effects of TJ-9 on these productions; and (3) effects of each of its herb components on cytokine production in cell fractions. Results showed that without stimulants, IL-10 production in mononuclear cells of hepatitis B and C patients was significantly lower than that of healthy subjects (P < .01). IL-10 production induced by either phytohemagglutinin (PHA) or pokeweed mitogen (PWM) in mononuclear cells of hepatitis C patients were significantly lower than in patients with hepatitis B (P < .01) and healthy subjects (P < .05). IL-10 production induced by anti-CD3 or lipopolysaccharide (LPS) was significantly lower than in healthy subjects (P < .05). The addition of TJ-9 to the cultures strongly induced IL-10, and this induction was mainly attributable to the effects of 2 components (scutellaria root and glycyrrhiza root) on the monocyte/macrophage fraction. The production of IL-4 and IL-5 in cultures with concanavalin A (conA) was significantly higher in patients with hepatitis C than in the healthy subjects (P < .01; P < .05), but the addition of TJ-9 suppressed these increases by 25% to 33% (P < .01). Therefore, TJ-9 could adjust the decreased IL-10 production and the increased IL-4 and IL-5 production of mononuclear cells from patients with hepatitis C. Moderate regulation of the cytokine production system in patients with hepatitis C by using TJ-9 may be useful in the prevention of disease progression.