bluuebunny/crossref_metadata_2025 huggingface dataset:
Biliary excretion in Sprague-Dawley and Gunn rats during manganese-bilirubin-induced cholestasis
Authors: Ayotte Pierre , Plaa Gabriel L.
Published: March 2007

We previously showed that alterations of the bile canalicular membrane are likely to occur following a cholestatic regimen composed sequentially of manganese and bilirubin. The present study was designed primarily to investigate the biliary excretion of organic bile constituents following administration of the manganese-bilirubin combination. Experiments in hyperbilirubinemic Gunn rats were also performed to determine whether the unconjugated or the conjugated form of bilirubin is involved in this cholestatic interaction. Male Sprague-Dawley rats and male homozygous Gunn rats were given the following (i.v.): (a) manganese (4.5 mg per kg); (b) unconjugated bilirubin (25 mg per kg); (c) bilirubin ditaurate (38 mg per kg); (d) manganese-unconjugated bilirubin, or (e) manganese-bilirubin ditaurate. Bile flow was measured and bile was analyzed for manganese, total bilirubin, bile salts, cholesterol and phospholipid content. The results show that: (i) manganese-unconjugated bilirubin treatment caused about a 50% reduction in bile flow in Sprague-Dawley rats, whereas in Gunn rats the manganese-bilirubin ditaurate treatment resulted in about a 75% reduction, and (ii) in both strains, bile salt excretion was not appreciably modified during the cholestatic phase, as biliary bile salt concentration increased. The results suggest that although important differences regarding the form of bilirubin apparently exist, unconjugated bilirubin could be implicated in the cholestatic interaction in both strains of rats. Manganese-bilirubin-induced cholestasis is not related to a defect in bile salt excretion. The latter supports our contention that diminished canalicular membrane permeability to water is likely to be a key factor in this form of experimental cholestasis.
Antibodies to translation products of the pre-S1 and pre-S2 regions of the envelope gene of hepatitis B virus in fulminant hepatitis B
Authors: Ise Iku , Tsuda Fumio , Aihara Shinobu , Machida Atsuhiko , Takai Emiko , Miyamoto Hideaki , Akahane Yoshihiro , Miyakawa Yuzo , Mayumi Makoto
Published: March 2007

Sera from 11 patients with fulminant hepatitis B were tested for antibodies to translation products of the pre-S1 and pre-S2 regions of hepatitis B virus of IgM, IgA and IgG classes, as well as of IgA1, IgA2 and SIgA, with solid-phase enzyme immunoassays using native viral polypeptides. Antibodies to pre-S1 region product of IgM and/or IgA class were detected invariably in six patients who still had detectable hepatitis B surface antigen in serum at the time of clinical presentation. The remaining five patients who had lost HBsAg at presentation had antibodies to pre-S region products of various immunoglobulin classes in higher titers. The five patients with fulminant hepatitis without HBsAg had higher levels of IgA antibodies to pre-S region products than the seven patients with nonfulminant acute hepatitis B who had lost HBsAg: IgA antibody to pre-S1 region product (75.6 ± 63.8 vs. 2.9 ± 3.2, p < 0.01) and IgA antibody to pre-S2 region product (28.9 ± 25.3 vs. 4.2 ± 6.9, p < 0.01). IgA antibodies to pre-S1 and pre-S2 region products were invariably polymeric in fulminant hepatitis B. These findings are compatible with the hypothesis that a heightened humoral antibody response to pre-S1 and pre-S2 region products occurs early during the course of fulminant hepatitis B, participating in severe hepatic injury and early clearance of virus characteristic of this disease.
Comparison of the hemodynamic responses to ketanserin and prazosin in portal hypertensive rats
Authors: Cummings Susan A. , Kaumann Alberto J. , Groszmann Roberto J.
Published: March 2007

Ketanserin, a serotonin antagonist, is effective in lowering portal pressure in a rat model of portal hypertension. As ketanserin has α1-adrenoceptor-blocking properties in addition to its serotonin-blocking effects, we sought to define further the mechanism of ketanserin’s portal pressure-lowering effect. We attempted to determine whether the portal pressure-reducing effect of ketanserin was due to the unspecific effect of arterial blood pressure reduction mediated by α1-adrenoceptor blockade or to serotonin receptor-blocking properties of ketanserin. The hemodynamic action of prazosin and α1-adrenoceptor antagonist and ketanserin were compared in portal hypertensive rats in which the arterial pressure was equally reduced by both agents. The portal pressure was significantly lower in the ketanserin-treated group (11.3 ± 0.4 mm Hg) when compared to the saline-treated group (13.6 ± 0.7 mm Hg). The portal pressure was not significantly lower in the prazosin-treated group when compared to the saline-treated group (12.3 ± 0.5 vs. 13.6 ± 0.7 mm Hg, respectively). The same relationship held true for portal venous inflow and cardiac output. For each measurement, results in the ketanserin group were significantly lower when compared to the saline-treated group. These data in the prazosin-treated group were similar to data in the saline-treated group. The differences between the effect of ketanserin and prazosin were obtained despite similar blood pressure decreases. Ketanserin produced an 18% decrease and prazosin a 14% decrease in blood pressure when values were compared to their preinjection baselines. Ketanserin at the dose used lowers portal pressure primarily via serotonin blockade; α1-adrenoceptor blockade and arterial hypotension appear to play a lesser role. This finding further supports a role for serotonin in portal hypertension.
A lack of direct role of hepatitis B virus in the activation of ras and c-myc oncogenes in human hepatocellular carcinogenesis
Authors: Lee Hyo-Suk , Rajagopalan M. S. , Vyas Girish N.
Published: March 2007

This study was performed to determine the relationship of the activation of ras and c-myc oncogenes in human hepatocellular carcinoma to the hepatitis B virus gene expression or the presence of hepatitis B virus DNA/RNA at the cellular level. This was done using immunocytochemical analysis with two different antibodies on serial sections. In addition, immunocytochemical assay for the detection of ras p21 or c-myc protein was performed in combination with in situ hybridization for hepatitis B virus DNA/RNA using 35S-labeled hepatitis B virus DNA as a probe. Investigation of a total of 14 paired human hepatocellular carcinoma and adjacent nontumorous hepatic tissues revealed enhanced expression of ras p21 in one human hepatocellular carcinoma whereas c-myc protein was found in one paired human hepatocellular carcinoma and nontumorous tissue of the same patient. Only a small proportion of human hepatocellular carcinoma cells or hepatocytes among a large number of cells on a given section showed enhanced expression, and the distribution of the oncogene product-expressing cells was focal. However, the cells over-expressing these oncogenes did not show hepatitis B surface antigen in the serial sections. Furthermore, the combined immunocytochemical and in situ hybridization assays revealed that human hepatocellular carcinoma cells overexpressing ras p21 did not show hepatitis B virus DNA/RNA, whereas some human hepatocellular carcinoma cells and nontumorous hepatocytes located away from the foci of oncogene-expressing cells gave positive signals. These findings suggest that continued expression of HBsAg or the presence of hepatitis B virus DNA/RNA in a given human hepatocellular carcinoma cell is not necessary for enhanced expression of ras or c-myc proteins. We conclude that HBsAg expression or hepatitis B virus DNA/RNA may not have a direct role in the activation of ras and c-myc oncogenes.
Effects of bile acid administration on bile acid synthesis and its circadian rhythm in man
Authors: Poole Pete A. , Duane William C.
Published: March 2007

In man bile acid synthesis has a distinct circadian rhythm but the relationship of this rhythm to feedback inhibition by bile acid is unknown. We measured bile acid synthesis as release of 14CO2 from [26-14C]Cholesterol every 2 hr in three normal volunteers during five separate 24-hr periods. Data were fitted by computer to a cosine curve to estimate amplitude and acrophase of the circadian rhythm. In an additional six volunteers, we measured synthesis every 2 hr from 8:00 a.m. to 4:00 p.m. only. During the control period, amplitude (expressed as percentage of mean synthesis) averaged 52% and acrophase averaged 6:49 a.m. During administration of ursodeoxycholic acid (15 mg per kg per day), synthesis averaged 126% of baseline (p < 0.1), amplitude averaged 43% and acrophase averaged 6:20 a.m. During administration of chenodeoxycholic acid (15 mg per kg per day), synthesis averaged 43% of baseline (p < 0.001), amplitude averaged 53% and acrophase averaged 9:04 a.m. Addition of prednisone to this regimen of chenodeoxycholic acid to eliminate release of 14CO2 from corticosteroid hormone synthesis resulted in a mean amplitude of 62% and a mean acrophase of 6:50 a.m., values very similar to those in the baseline period. Administration of prednisone alone also did not significantly alter the baseline amplitude (40%) or acrophase (6:28 a.m.). We conclude that neither chenodeoxycholic acid nor ursodeoxycholic acid significantly alters the circadian rhythm of bile acid synthesis in man. Moreover, because this method of measuring synthesis does not require subtraction of large amounts of exogenous bile acid, these data also demonstrate more clearly than ever before that chenodeoxycholic acid causes inhibition of total bile acid synthesis while ursodeoxycholic acid causes either no change or a slight increase in synthesis.
Simvastatin, a competitive inhibitor of HMG-CoA reductase, lowers cholesterol saturation index of gallbladder bile
Authors: Duane William C. , Hunninghake Donald B. , Freeman Martin L. , Pooler Pete A. , Schlasner Linda A. , Gebhard Roger L.
Published: March 2007

We tested the possibility that simvastatin, a competitive inhibitor of HMG-CoA reductase related to mevinolin, might alter cholesterol saturation of gallbladder bile. Ten patients with Type IIa or IIb hypercholesterolemia underwent bile sampling before, and again after, treatment with 20 or 40 mg per day simvastatin for 7 to 13 weeks. Mean cholesterol saturation index of gallbladder bile fell from 1.01 to 0.77 during simvastatin treatment (p < 0.01). This finding strongly suggests that treatment with HMG-CoA reductase inhibitors will not predispose to development of cholesterol gallstones. Indeed, it raises the possibility that such inhibitors might have a future role to play in treatment of gallstones.
Liver look-alike: Hepatoid ovarian carcinoma
Authors: Lefkowitch Jay H.
Published: March 2007

Five cases of ovarian carcinoma with hepatoid features, three of them primary and two probably primary, are described. The tumor cells were arranged predominantly in sheets and contained moderate to abundant amounts of eosinophilic cytoplasm; varying numbers of tumor cells stained immunohistochemically for alpha-fetoprotein. In contrast to the much younger age range of patients with ovarian hepatoid yolk sac tumors, the ages of the five patients with hepatoid carcinomas ranged from 42 to 78 (average, 63 years), and none of them had gonadal dysgenesis or recognizable germ cell components within their tumors. All the tumors presented as adnexal masses; in four cases they were Stage III and in one case, Stage IIB; this last tumor spread to the upper abdomen within 4 years. In three cases the clinical course and pathology findings indicated that the tumor had originated in the ovary; in the remaining two cases the tumors were interpreted as only probably primary in the ovary. Hepatoid carcinomas must be distinguished from other ovarian neoplasms, especially from hepatoid yolk sac tumors.
Increased hepatic oxygen consumption during alcohol withdrawal
Authors: Benoit Joseph N. , Granger Neil D.
Published: March 2007

Catecholamines, which are elevated during alcohol withdrawal, can alter hepatic blood flow and increase hepatic oxygen consumption. We hypothesized that, in the withdrawal state, hepatic oxygen consumption and delivery could be altered in relation to an increased sympathetic activity. Thirteen chronic alcoholics were studied 34-72 h after withdrawal and 10 days later (control period) using conventional hemodynamic methods. As compared with the control period, splanchnic oxygen uptake was elevated at withdrawal (74.5 ± 27.1 vs 59.2 ± 16.8 ml/min, p < 0.025) and its variation was correlated with that of plasma epinephrine (r = 0.70, p < 0.01). The hepatic venous oxygen content was reduced at withdrawal (113 ± 22 vs 126 ± 21 ml/L, p < 0.025) and correlated inversely with plasma norepinephrine levels (r = 0.56, p < 0.01). We conclude that, during alcohol withdrawal in humans, hepatic energy expenditure may be elevated in relation to epinephrine secretion and that sympathetic overactivity may hinder the adaptive response in hepatic blood flow. The wide range in sympathetic nervous response to alcohol withdrawal could explain some differences in individual susceptibility to liver damage caused by alcohol.
Hepatitis B virus infection and renal transplantation
Authors: Garcia Gabriel , Hollinger Blaine F.
Published: March 2007

Hepatitis B virus (HBV) infection may induce severe hepatitis and affect long-term survival of kidney transplant recipients. Persistent viral infection has been shown to occur despite the absence of usual serologic markers. The liver and serum HBV deoxyribonucleic acid (DNA) status of 90 patients were studied prospectively; recently transplanted patients, both hepatitis B virus surface antigen (HBsAg)-positive and negative, with and without liver disease, were investigated with HBV serology, serum HBV DNA, and liver histology. Thirty-four patients had detectable HBsAg, and 21 had viral multiplication at the time of transplantation. Serial HBV DNA determinations performed in 57 of 90 patients disclosed (a) reactivation of HBV replication in 11 of 12 HBsAg-positive patients, (b) increase of viral replication when positive on the initial sample in 6 of 11 patients, and (c) development of HBV replication in 7 of 35 of the HBsAg-negative patients. Moreover, liver HBV DNA studies showed a statistical correlation between the presence of integrated liver HBV DNA and chronic hepatitis in HBsAg-negative patients. This study demonstrates prospectively the significant association of HBsAg-positive as well as HBsAg-negative HBV infection with chronic hepatitis and suggests that immuno-suppressive therapy may enhance the viral replication in both HBsAg-positive and negative subjects.
Distal splenorenal vs. portal-systemic shunts after hemorrhage from varices: A randomized controlled trial
Authors: Grace Norman D. , Conn Harold O. , Resnick Robert H. , Groszmann Roberto J. , Atterbury Colin E. , Wright Stephen C. , Gusberg Richard J. , Vollman Rudolph , Garcia-Tsao Guadalupe , Fisher Rosemarie L. , O’Hara Edward T. , McDermott William V. , Maselli Peter J. , Widrich Warren , Matloff Daniel S. , Horst Douglas , Banks Naomi , Alberts Jeanne
Published: March 2007

Between 1975 and 1983, 303 cirrhotic patients with endoscopically proven major variceal hemorrhage were admitted to the participating hospitals of the Boston-New Haven Collaborative Liver Group. Of these, 274 were evaluated for admission to a prospective, randomized controlled trial comparing portal-systemic shunts with distal splenorenal shunts. The criteria for inclusion were as follows: (i) a portohepatic pressure gradient ≥ 12 mmHg; (ii) angiographic evidence of antegrade portal venous flow; (iii) angiographic demonstration that the inferior vena cava and portal, splenic and left renal veins were anatomically suitable for either a portal-systemic or distal splenorenal shunt, and (iv) the patient was a reasonable operative risk. Eighty-one patients from the six participating hospitals fulfilled the criteria and consented to participate. Thirty-eight patients were randomly assigned to have portal-systemic shunt and 43 to have distal splenorenal shunt.

After a follow-up period of 11 years (mean = 3.5 years for all patients), survival was found to be similar in the two groups of patients. The 30-day operative mortality was 13% for the portal-systemic shunt group and 9% for the distal splenorenal shunt patients. Late mortality was 55% for the portal-systemic shunt and 37% for the distal splenorenal shunt group. Total mortality was 68% for the portal-systemic shunt and 46% for the distal splenorenal shunt group. None of these differences is statistically significant. In those patients who survived >30 days after surgery, recurrent variceal hemorrhage occurred in four (12%) in the portal-systemic shunt group compared to seven in the distal splenorenal shunt group (18%) (NS). Portal-systemic encephalopathy occurred in 15 (45%) of the operative survivors in the portal-systemic shunt group compared to 20 (51%) in the distal splenorenal shunt group. Severe portal-systemic encephalopathy was observed with equal frequency in the two groups. There was no difference in the time of onset nor the severity of encephalopathy in the two groups.

We conclude that the operative mortality and cumulative survival are similar for the two operations and that the frequency and severity of hepatic encephalopathy following distal splenorenal shunt are similar to that after portal-systemic shunt. Based on our observations and previously published data, recurrent hemorrhage from varices appears to be more frequently prevented by portacaval anastomosis than by distal splenorenal shunt.
Biliary β2-microglobulin in liver allograft rejection
Authors: Adams David H. , Burnett David , Stockley Robert A. , Hubscher Stefan G. , McMaster Paul , Elias Elwyn
Published: March 2007

β2-Microglobulin, which is associated with HLA class 1 antigens, was assayed in bile and serum from 19 patients following 22 liver transplants. Serum levels were elevated in all posttransplant patients irrespective of the presence of rejection. In contrast, biliary levels were significantly higher during episodes of acute rejection compared with posttransplant cholangitis (p < 0.01), stable graft function (p < 0.0001) and nontrans-plant samples (p < 0.0001). When bile/serum ratios were studied, the difference between the rejection and the other groups was even more significant, and if a ratio of 0.2 was considered diagnostic of rejection, the test had a sensitivity of 96%, a specificity of 87% with an accuracy of 90%. Therefore, these results suggest that the measurement of bile/serum ratios of β2-microglobulin following liver transplantation may be useful in diagnosing acute rejection.

When bile/serum ratios of β2-microglobulin were compared with those for other proteins, there was strong evidence to suggest that local release accounted for most of the increased biliary β2-microglobulin during rejection. These results provide further evidence that HLA class 1 antigens on the biliary epithelium may be important in liver allograft rejection.
The development of the intrahepatic bile ducts in man: A keratin-immunohistochemical study
Authors: Van Eyken Peter , Sciot Raf , Callea Francesco , Steen Kris Van Der , Moerman Philip , Desmet Valeer J.
Published: March 2007

The development of the intrahepatic bile ducts in man was studied using an immunohistochemical technique on 56 liver specimens ranging in age from 6 weeks of gestation to 8 months after birth. On paraffin sections, two monoclonal anticytokeratin antibodies (CAM 5.2 and KL-1) that normally stain both hepatocytes and bile duct cells and two polyclonal anticytokeratin antisera that in normal adult liver stain bile ducts only were applied. For immunohistochemical staining of cryostat sections (only available from 14 weeks of gestation on), four monoclonal antibodies specifically directed against individual cytokeratin polypeptides 7, 8, 18 and 19 were used. Adult human hepatocytes contain cytokeratin 8 and 18 whereas bile duct cells also express cytokeratin 7 and 19 in addition to cytokeratin 8 and 18. On paraffin sections, primitive hepatocytes were stained with monoclonal antibodies CAM 5.2 and KL-1 from 6 weeks of gestation on. On cryostat sections, they were positive with monoclonal antibodies anticytokeratin 8 and 18 from the earliest time point examined (14 weeks). From 9 weeks of gestation on, portal vein branches were surrounded by a layer of cells showing a stronger positive reaction with monoclonal antibodies CAM 5.2 and KL-1 on paraffin sections and with monoclonal antibodies anti-cytokeratin 8 and 18 on cryostat sections (only available from 14 weeks on).

This layer, referred to as the ductal plate, first appeared around large portal vein branches close to the hilum and subsequently around more peripheral branches. The duct plates became duplicated over variably long segments of their perimeter, lumina appeared and tubular structures were formed. The latter gradually became incorporated in the connective tissue surrounding the portal vein, resulting in the appearance of individualized bile ducts. Ductal plate cells were stained by both polyclonal anticytokeratin antisera on paraffin sections. On cryostat sections (available from 14 weeks of gestation on), they were immunoreactive for cytokeratin 19 but negative with the monoclonal antibody directed against cytokeratin 7 until 20 weeks of gestation.

From then on, weakly positive staining for cytokeratin 7 was detected, but staining intensity subsequently increased and reached the level observed in adult liver at 1 month after birth. At birth, the smallest branches of the portal vein were still surrounded by a discontinuous ductal plate. We conclude that intrahepatic bile duct cells develop from hepatocytes around branches of the portal vein. During the phenotypic shift toward bile duct type cells, hepatocytes first display increased reactivity for cytokeratin 8 and 18 and express cytokeratin 19, followed only later on by cytokeratin 7. The intrahepatic bile duct system is still immature at birth.
Hepatic zinc content in patients with various stages of alcoholic liver disease and in patients with chronic active and chronic persistent hepatitis
Authors: Bode Johann Christian , Hanisch Peter , Henning Harald , Koenig Wolfgang , Richter Friedrich-Wilhelm , Bode Christiane
Published: March 2007

The hepatic zinc content was determined in liver biopsies of patients with alcoholic and nonalcoholic liver disease using proton-induced X-ray emission. The values obtained in postmortem specimens of the liver from 27 patients with no evidence of acute or chronic liver disease served as controls. The mean value and the range of the zinc content in the controls (75 ± 24 ppm wet weight) are in good agreement with those reported in the literature. The hepatic zinc content in the control group showed no significant age or sex dependence. The mean zinc content was significantly decreased in all groups of patients with alcoholic liver disease. The decrease was comparable in biopsies from patients with alcoholic fatty liver (−56.7%, n = 12), mild alcoholic hepatitis (−50.5%, n = 6) and alcoholic cirrhosis (−45.6%, n = 10). The hepatic zinc content was also distinctly reduced in patients with chronic active hepatitis (−60.3%, n = 15) and in those with chronic persistent hepatitis (−44.9%, n = 8). The estimation of the zinc content in subcellular fractions of the liver performed in postmortem specimens from seven patients with alcoholic liver cirrhosis and in six controls revealed a significant reduction in the zinc content in the fraction containing cell nuclei and membranes and in the mitochondrial fraction. A similar decrease was seen in the 100,000 g supernatant; however, the difference did not attain statistical difference. The zinc content of the microsomal fraction in the controls was lower than in the other three cell fractions. There was no significant difference in microsomal zinc content between the samples of the two groups studied. The results of this study underline the fact that zinc deficiency in the liver occurs not only in cirrhotics but also in less advanced alcoholic and nonalcoholic liver disease.
Altered platelet function in cirrhosis of the liver: Impairment of inositol lipid and arachidonic acid metabolism in response to agonists
Authors: Laffi Giacomo , Cominelli Fabio , Ruggiero Marco , Fedi Sandra , Chiarugi Vincenzo P. , La Villa Giorgio , Pinzani Massimo , Gentilini Paolo
Published: March 2007

Hemorrhagic disorders are common in patients with liver cirrhosis and result from several factors including impaired platelet function. We evaluated platelet aggregation and arachidonic acid metabolism in response to standard agonists in platelet-rich plasma from 12 cirrhotic patients with mild impairment of liver function (Child A), 12 patients with severe liver dysfunction (Child B and C) and 12 healthy subjects. Platelet aggregation and thromboxane A2 production were consistently reduced in patients with severe liver impairment. To determine whether the platelet dysfunction is due to an intrinsic platelet defect or a circulating inhibitor, we measured platelet aggregation and thromboxane A2 synthesis on washed platelets in healthy subjects and in Child B and C patients. The aggregating response of washed platelets in response to thrombin, collagen and arachidonic acid was markedly reduced, suggesting an intrinsic platelet defect. The biochemical events underlying platelet aggregation were investigated by prelabeling platelets with [1-14C]arachidonie acid. Thrombin-induced activation of phospholipase C (measured as the release of [1-14C]phosphatidic acid) and phospholipase A2 (measured as the release of [1-14C]arachidonic acid and its metabolites) was greatly impaired in platelets from patients with severe liver impairment. We conclude that in advanced cirrhosis there is a severe reduction in platelet aggregatory response to physiologic agonists due to an intrinsic platelet defect which is related to an impairment of the platelet transmembrane signaling mechanism induced by receptor stimulation.
In vitro toxicity of hydrogen peroxide against normal vs. tumor rat hepatocytes: Role of catalase and of the glutathione redox cycle
Authors: Mavier Philippe , Guigui Bernard , Preaux Anne-Marie , Rosenbaum Jean , Lescs Marie-Claude , Zafrani Elie Serge , Dhumeaux Daniel
Published: March 2007

Hydrogen peroxide produced by stimulated phagocytic cells or during the metabolism of drugs, is toxic to various cell types. The aim of this study was to investigate its toxicity against normal vs. tumor rat hepatocytes. Isolated normal hepatocytes and tumor hepatocytes from three hepatocarcinoma cell lines, Fao, C2 (Faof1 C2) and HTC, were incubated in the presence of a H2O2-generating system consisting of glucose and varied concentrations of glucose oxidase. The toxicity of H2O2 was quantified by measuring the percentage of lactate dehydrogenase activity released in the culture medium after various times of incubation. By comparison to normal hepatocytes, tumor hepatocytes exhibited an increased susceptibility to lysis by H2O2. At a concentration of 100 mU per ml, glucose oxidase induced a lactate dehydrogenase activity release of only 6.1 ± 2.2% (mean ± S.E.) from normal hepatocytes and of 71.0 ± 2.9, 45.5 ± 2.5 and 34.7 ± 3.4% from Fao, C2 and HTC cells, respectively, after an 18-hr incubation. At a concentration of 10 mU per ml, glucose oxidase had no toxic effect to normal hepatocytes or HTC cells, whereas it induced a lactate dehydrogenase activity release of 58.7 ± 7.6 and 51.2 ± 5.6% from Fao and C2 cells, respectively. In addition, the time courses of lactate dehydrogenase activity release, studied with 500 mU per ml glucose oxidase, demonstrated that Fao cells, C2 cells and, to a lesser degree, HTC cells were lysed more rapidly than normal hepatocytes. The toxicity of glucose oxidase was suppressed by the addition of catalase, indicating that it was actually mediated by H2O2. Catalase activity expressed per cell number and the components of the glutathione redox cycle were decreased in tumor cells by comparison to normal hepatocytes. In addition, treatment of normal hepatocytes with aminotriazole, an inhibitor of catalase, and with 1,3-bis(2-chloroethyl)-1-nitrosourea, an inhibitor of glutathione reductase, rendered these cells as susceptible as tumor hepatocytes to the effects of H2O2. In conclusion, tumor hepatocytes were more susceptible to the toxic effect of H2O2 than normal hepatocytes. This difference is probably due to a decrease in the H2O2 detoxication systems that we studied, i.e. catalase and glutathione redox cycle, in tumor cells.
Hepatocellular carcinoma in corticosteroid-treated severe autoimmune chronic active hepatitis
Authors: Wang Kenneth K. , Czaja Albert J.
Published: March 2007

To determine the frequency of hepatocellular cancer in corticosteroid-treated severe autoimmune chronic active hepatitis and to identify risk factors for its development, 124 patients who were selected by uniform criteria, treated comparably and followed systematically for 111 ± 6 months were evaluated. Hepatocellular cancer was diagnosed in three patients (2%) after 66, 99 and 174 months of observation, respectively. The incidence of hepatocellular cancer was 1 per 350 patient-years of follow-up. All three patients with hepa-tocellular cancer had cirrhosis for at least 5 years. The frequency of neoplasm in patients with cirrhosis of at least 5 years’ duration was 7%. The incidence of hepatocellular cancer in these patients with cirrhosis was 1 per 182 patient-years of follow-up, and the probability of tumor was 29% after 13 years. Late elevation of the serum α-fetoprotein level was associated with the presence of neoplasm but normal levels did not exclude the diagnosis. We conclude that patients with corticosteroid-treated severe autoimmune chronic active hepatitis are at risk for hepatocellular cancer. This risk is greatest in patients with cirrhosis for at least 5 years. Such patients are candidates for cancer surveillance.
The gold standard serologic marker for hepatitis B virus infectivity
Authors: Seeff Leonard B.
Published: March 2007

The authors tested, by molecular hybridization, for hepatitis B virus DNA in serum specimens of 182 asymptomatic hepatitis B surface antigen (HBsAg) Greek carriers who were heterosexual partners of patients with acute hepatitis B (group A: 96 cases) or healthy subjects who were susceptible to hepatitis B (group B: 86 cases). The mean age (34.1 ± 10.4 vs. 33.9 ± 8.4 years) and the mean duration of sexual contact (6.9 ± 8.9 vs. 7.2 ± 6.3 years) were similar in the two groups of carriers. Hepatitis B virus DNA was detected significantly more frequently in group A than in group B (59.4% vs. 11.6%, p < 0.001). In particular, in group A, hepatitis B virus DNA was detected in 96.9% of hepatitis B e antigen (HBeAg)-positive and 41% of antibody to HBeAg (anti-HBe)-positive carriers. In contrast, in group B, hepatitis B virus DNA was identified in only 10.8% of anti-HBe-positive carriers (p < 0.001). These differences were especially significant in the young and middle-aged carriers (16-49 years old) and during the first four years of sexual contact. These data suggest that 1) there is a positive correlation between the presence of hepatitis B virus DNA in serum and the epidemiologic evidence of sexual transmission of hepatitis B virus, 2) hepatitis B virus DNA is a better indicator of infectivity than HBeAg/anti-HBe, and 3) the detection of hepatitis B virus DNA in serum probably identified carriers with high infectivity and potentially higher risk of transmitting hepatitis B virus to their sexual partners.
Cocaine-induced hepatotoxicity
Authors: Porter John M. , Sussman Marc S. , Rosen Gerald M.
Published: March 2007

A patient with hepatonecrosis associated with cocaine use is presented. Postmortem examination of the liver showed marked periportal inflammation and necrosis, and mild diffuse fatty infiltration. These pathologic findings are identical to those previously reported in a mouse model of cocaine hepatotoxicity.
Different capacities for amino acid transport in periportal and perivenous hepatocytes isolated by digitonin/collagenase perfusion†
Authors: Burger Hans-Jörg , Gebhardt Rolf , Mayer Claus , Mecke Dieter
Published: March 2007

Periportal and perivenous hepatocytes were isolated from rat liver by digitonin/collagenase perfusion for investigating the acinar heterogeneity of amino acid transport activities related to glutamine and ammonia metabolism. Immunocytochemical staining of the respective subpopulations for glutamine synthetase demonstrated that periportal subpopulations were essentially free of glutamine synthetase-positive cells, whereas perivenous subpopulations showed a 2- to 3- fold enrichment of glutamine synthetase-positive hepatocytes. The high perivenous/periportal ratio of 59 found for glutamine synthetase activity as well as the perivenous/periportal ratios of other marker enzymes further indicated the good separation of periportal and perivenous cells.

α-Aminoisobutyric acid, histidine and glutamate were used to determine the distribution pattern of amino acid transport systems A, N and G−, as well as of the sodium-independent uptake of these compounds 1 hr after isolation and after maximal hormonal stimulation during primary culture. The strong heterogeneity of the sodium-independent transport of histidine, characterized by higher perivenous transport rates [perivenous/periportal ratio: 1.5 (1 hr) to 3.5 (48 hr)], suggests a significant role of facilitated diffusion, presumably in glutamine export. Conversely, the strong heterogeneity of the sodium-dependent glutamate transport (System G−) characterized by higher uptake rates in nonstimulated [perivenous/periportal ratio: 6.6 (1 hr)] and in hormonally treated perivenous hepatocytes (perivenous/periportal ratio: 2.2) reflects its possible significance with respect to the substrate availability for glutamine synthesis. The observed heterogeneities provide a basis for understanding how substrate fluxes related to glutamine metabolism might be established and regulated. In addition, our findings indicate that periportal and perivenous cells retain their zonal characteristics with respect to amino acid transport in primary culture for at least 48 hr.
Proline-incorporating cells in chronic active liver diseases
Authors: Hassan Giorgio , Stefanini Stefania , Bargagli Anna Maria , Autuori Francesco
Published: March 2007

The incorporation of 3H-proline in cells of liver biopsy specimens from patients with chronic active liver diseases has been studied by light and electron microscopic autoradiography. The labeled proline is incorporated by hepatocytes of the external rows of the residual liver lobule, by the cells of the proliferating bile ductule and very actively by the plasma cells localized at the boundary between the inflammatory infiltrate and the liver lobule. These plasma cells, which are often in close contact with the hepatocytes at the edge of the liver lobule, appear to be either negative or positive after the immunohistochemical tests for the k and λ chains of immunoglobulins. Results are discussed in relation to both the synthesis of collagen and the role of the immunocompetent cells during the process of the piecemeal necrosis.
A simplified single stage total hepatectomy in the rat with maintenance of gastrointestinal absorptive function
Authors: Yamaguchi Yasuo , Bollinger Randal R. , Defaria Eliana , Landis Barry , Quarfordt Steven
Published: March 2007

A technique is described to remove the entire liver in a single stage with preservation of intestinal absorptive function. An inverted V-shape polyethylene cannula, either heparin bonded or silicon coated, was inserted into the portal vein and inferior vena cava to maintain venous return from the splanchnic and lower caval regions of the anhepatic rat. Blood glucose fell at a rate of 7 to 11 mg per hr per total plasma volume (4% body weight), usually resulting in hypoglycemia within the initial 2 hr. Euglycemia could be maintained in the first 3 hr after hepatectomy with hourly intravenous infusions of 2.5 to 5 mg per 100 gm body weight of glucose. Larger infusionś of glucose (10 to 12.5 mg per hr per 100 gm body weight) were necessary for normal levels at later times. A 0.5 gm per 100 gm rat weight intestinal glucose bolus restored euglycemia for at least a 2-hr interval. Intestinal absorption of cholesterol and oleic acid was demonstrated in the anhepatic rat, although the latter was not so efficiently absorbed as in the control. The plasma cholesterol decreased with time in the anhepatic rat. Prompt increases were observed in plasma free fatty acid and glycerol concentrations after hepatectomy. Progressive increases in both direct and indirect plasma billirubin levels were noted after hepatectomy. With appropriate maintenance of blood sugar, survival of 36 hr was observed. This procedure for single stage total hepatectomy in the rat can be performed in less than 30 min. The model is particularly useful for studies of the influence of the liver on post-absorptive metabolism.
Combination of ketanserin and verapamil or propranolol in patients with alcoholic cirrhosis: Search for an additive effect
Authors: Hadengue Antoine , Moreau Richard , Cerini Raimondo , Koshy Abraham , Lee Samuel S. , Lebrec Didier
Published: March 2007

Drugs reported to reduce portal pressure through different mechanisms were combined in the hope of either additive portal hypotensive effects in “responders,” or inducing a portal hypotensive effect in “nonresponders” to the initial drug. Seven patients with alcoholic cirrhosis received verapamil, 10 mg i.v., and, 60 min later, ketanserin, 5 mg i.v. Verapamil decreased heart rate and increased free hepatic venous pressure but had no effect on hepatic venous pressure gradient or azygos blood flow. When combined with verapamil, ketanserin significantly diminished wedged hepatic venous pressure and hepatic venous pressure gradient. Ten other patients with alcoholic cirrhosis received propranolol, 15 mg i.v., and 45 min later, ketanserin, 5 mg i.v. In all patients, heart rate, cardiac index and azygos blood flow significantly decreased after propranolol. After propranolol alone, however, wedged hepatic venous pressure decreased in only five patients, responders. In five other patients, defined as nonresponders, propranolol did not decrease this pressure. The addition of ketanserin to propranolol induced further significant reduction in wedged hepatic venous pressure, hepatic venous pressure gradient and azygos blood flow. Among the five nonresponders, three had a reduced wedged hepatic venous pressure after ketanserin was combined. We conclude that verapamil does not reduce portal pressure or collateral blood flow in patients with alcoholic cirrhosis. The splanchnic hemodynamic effects of propranolol and ketanserin appear to be independent and additive, without significant systemic alteration.
Defective response to interferons in cells transfected with the hepatitis B virus genome
Authors: Onji Morikazu , Lever Andrew M. L. , Saito Izumu , Thomas Howard C.
Published: March 2007

The interferon responsiveness of two cell lines transfected with the hepatitis B virus genome was investigated. A cosmid vector containing multiple copies of the hepatitis B virus genome was transfected into FL5-1 cells; it reduced their sensitivity to interferons as measured by inhibition of the cytopathic effect of Sindbis virus challenge. Similar vectors transfected into HeLa cells reduced their sensitivity to interferon as measured by production of β2-microglobulin.

This resistance to interferon in hepatitis B virus-transfected cells may be a trans-acting phenomenon related to nucleotide homology between hepatitis B virus DNA and sequences regulating the interferon-induced antiviral system. Alternatively, other mechanisms involving transcription or translation products of hepatitis B virus may be responsible.

Hepatitis B virus-induced cellular resistance to the action of interferon may be important in maintaining the chronic carrier state.
Interferon-associated lymphocyte 2′,5′-oligoadenylate synthetase in acute and chronic viral hepatitis
Authors: Heathcote Jenny , Kim Young-In , Yim Colina K. , Lebrocq James , Read Stanley E.
Published: March 2007

Basal levels of the interferon-associated enzyme 2′,5′-oligoadenylate synthetase were studied in lymphocytes of 46 patients with acute viral hepatitis and in 46 patients with chronic hepatitis B. Measurement of in vitro production of 2′,5′-oligoadenylate synthetase following overnight incubation of lymphocytes with exogenous interferon was used to assess functional capacity of the lymphocyte interferon system. In acute hepatitis patients, an early but transient elevation of 2′,5′-oligoadenylate synthetase was observed; the mean level at 1 week was significantly greater than the mean level at 4 weeks after the onset of their illness (p<0.01). Serial 2′,5′-oligoadenylate synthetase levels did not identify those patients who were to progress to chronic hepatitis. Patients with chronic hepatitis B infection, regardless of background liver histology, generally had normal basal lymphocyte 2′,5′-oligoadenylate synthetase levels. In both acute viral hepatitis and chronic hepatitis B, there was an inverse correlation between basal 2′,5′-oligoadenylate synthetase level and 2′,5′-oligoadenylate synthetase response to overnight incubation with interferon, a finding that suggested a transient down regulation of interferon responsiveness. These findings provided no support for the hypothesis that there is an inherent or persistently induced deficiency in the interferon system in acute or chronic hepatitis B.
Detection of anti-liver cell membrane antibody using a human hepatocellular carcinoma cell line
Authors: Lobo-Yeo Ava , McSorley Claire , McFarlane Barbara M. , Mieli-Vergani Giorgina , Mowat Alex P. , Vergani Diego
Published: March 2007

A radioimmunometric technique for the detection of autoantibodies to liver membrane antigens has been developed using Alexander cells, a human hepatocellular carcinoma cell line. After incubation of Alexander cells with serum, antimembrane antibodies were detected by addition of 125I-labeled Protein A. Binding ratios in 15 children with uncontrolled autoimmune chronic active hepatitis and in seven children with primary sclerosing cholangitis were significantly higher than in 18 age-matched normal controls. Nine patients with inactive autoimmune chronic active hepatitis, 13 with α1-anti-trypsin deficiency and five with fulminant hepatic failure had ratios similar to controls. In nine patients with Wilson’s disease, there was a modest but significant increase in binding ratio. In four children with autoimmune chronic active hepatitis, binding ratios fell during effective immunosuppressive therapy. Sera from patients with systemic lupus erythematosus or rheumatoid arthritis gave normal results, excluding that binding derives from Fc-mediated immune complex capture. A positive correlation was found between Alexander cell binding values and anti-liver-specific protein antibody titers, suggesting that the two assays detect antibodies against shared antigenic determinants. The Alexander cell assay is a simple, rapid and sensitive technique to detect antibody to liver cell membrane antigens.
Floxuridine-induced sclerosing cholangitis: An ischemic cholangiopathy?
Authors: Ludwig Jurgen , Kim Chung H. , Wiesner Russell H. , Krom Ruud A. F.
Published: March 2007

A 43-year-old man underwent abdominoperineal resection of a rectal adenocarcinoma, and left hepatic lobectomy for a single metastasis. He then received hepatic artery infusions of floxuridine. The tumor did not recur, but sclerosing cholangitis and liver failure developed which necessitated orthotopic liver transplantation. In the hilus of the native liver, obstructive arteriopathy and portal venopathy were found. These lesions probably had been caused by drug-induced intravascular thrombosis. Thus, the sclerosing cholangitis that develops in many patients after floxuridine infusion may be ischemic rather than toxic. The patient described here is well, 14 months after orthotopic liver transplantation. Therefore, in some cases of floxuridine-induced cholangitis, liver transplantation appears to be indicated despite a history of metastasizing carcinoma.
Hepatic asialoglycoprotein receptor-mediated binding of human polymeric immunoglobulin A
Authors: Daniels Christopher K. , Schmucker Douglas L. , Jones Albert L.
Published: March 2007

In the rat, asialoorosomucoid and rat dimeric immunoglobulin A are both taken up by hepatocytes via receptor-mediated endocytosis. The fate of these two proteins, however, differs significantly. Rat dimeric IgA is taken up into smooth vesicles, transported to the bile canaliculus and secreted intact into the bile, whereas asialoglycoproteins are internalized via coated vesicles and transported to lysosomes for degradation. Recently, several studies both in the rat and in cultured human hepatoma cells have suggested that the receptor for asialoglycoproteins may play a role in the hepatic uptake and processing of human polymeric IgA. Using receptor-binding techniques, we have provided quantitative data for the competition of human monomeric, polymeric and secretory IgA with asialoorosomucoid for its receptor on liver plasma membrane preparations from rat, monkey and man. Some IgA molecules required desialylation with neuraminidase to enhance markedly their efficacy for asialoorosomucoid inhibition. Quantitatively, human IgA molecules showed an affinity for the ASOR receptor similar to that for asialoceruloplasmin. Rat dimeric IgA does not compete for this binding site. We conclude that human IgA can compete with ligands for the asialoglycoprotein receptor of rat, monkey and human liver. This receptor may provide an alternative pathway for the hepatic processing of IgA and IgA immune complexes when secretory component-mediated uptake is not available as in the monkey and man, particularly under pathological conditions where serum IgA concentrations accumulate to abnormally high levels.
Differential regulation of glutathione S-transferases in cultured hepatocytes
Authors: Abramovitz Mark , Ishigaki Seishi , Listowsky Irving
Published: March 2007

Specific cDNA probes were used to determine steady-state mRNA levels for the multiple glutathione S-trans-ferases in primary hepatocyte cultures. In the first 24 hr of culture, gene transcripts for the Ya family decreased sharply, Yb3 disappeared completely, but changes in levels of mRNA for Yb1 and Yb2 were smaller. These results suggest that the isoenzymes are regulated independently. Yp mRNA, which is present at greatly elevated levels in hyperplastic nodules and hepatocel-lular carcinomas but not in normal adult livers, was hardly detectable in freshly isolated hepatocytes, but Yp transcripts rapidly accumulated in the first 24 hr in culture and continued to increase for 72 hr. Decreased levels in Ya and Yc and increases in Yp were detected by immunoblotting methods, indicating that translation products changed together with mRNA levels in the cultured cells. The appearance of Yp transcripts in hepatocytes was effectively blocked by addition of dexa-methasone to the culture medium. Elevations of Yp levels are characteristic of the cell culture system and factors regulating Yp transcription in nodules and carcinomas may also be operative in cultured hepatocytes.