bluuebunny/crossref_metadata_2025 huggingface dataset:
Insulin Action in Cirrhosis
Authors: Taylor R. , Heine R. J. , Collins J. , James O. F.W. , Alberti K. G.M.M.
Published: March 2007

In vivo insulin sensitivity and adipocyte insulin binding and action were assessed in 16 patients with histologically proven hepatic cirrhosis and 11 age–, weight– and sex–matched normal control subjects. The cirrhotic group displayed impaired oral glucose tolerance, despite an exaggerated serum immunoreactive insulin response, and in vivo insulin resistance as assessed both by the euglycemic hyperinsulinemic clamp and the glucose–insulin infusion techniques. Adipocytes of the cirrhotic patients bound significantly less insulin than those of the control subjects (2.21 ± 0.12% vs. 2.64 ± 0.13%; p < 0.05). Although the adipocytes from the cirrhotic patients were less sensitive to insulin stimulation in vitro (half–maximal stimulation at 60.0 ± 8.0 vs. 21.8 ± 3.3 pM; p < 0.001), they exhibited higher maximum rates of lipogenesis. Comparison of the responses of the alcoholic, primary biliary cirrhosis and cryptogenic subgroups suggested pronounced differences in the maximum rates of lipogenesis. There were significant negative correlations between specific binding to adipocytes and both fasting serum immunoreactive insulin and in vivo insulin resistance as assessed by glucose–insulin infusion. Monocyte insulin binding was normal in the cirrhotic group and did not correlate with in vivo insulin resistance. It is concluded that both binding and postbinding defects in insulin target organ cells contribute to the marked in vivo insulin resistance of hepatic cirrhosis.
Liver Morphology in Southern African Blacks With Hepatocellular Carcinoma: A Study Within the Urban Environment
Authors: Paterson Alan C. , Kew Michael C. , Herman Allen A.B. , Becker Pieter J. , Hodkinson John , Isaacson Charles
Published: March 2007

Hepatocellular carcinoma has a lower prevalence and presents at a later age in urban Blacks than in rural Blacks. These differences have previously been shown not to be attributable to differences in serum hepatitis B virus markers. In the present study, the average age of patients with hepatocellular carcinoma in a developing urban Black population is shown to have risen from 38.9 to 56.5 years (p < 0.0001) over a 20–year interval, while the prevalence of co–existing cirrhosis has declined from 66 to 44% (p < 0.05) and tissue HBsAg positivity has fallen from 44 to 17.7% (p = 0.002). The lower prevalence of tissue HBsAg in the recent patients may be explained by their older age. Macronodular cirrhosis was present in 56% of cases in the earlier period but declined to 18.9% in the later period, with micronodular cirrhosis becoming the dominant nontumor pathology (p = 0.002). Liver damage attributable to the abuse of alcohol is now found in more than half of the cases (48/90) of hepatocellular carcinoma occurring in this population. The remainder show no changes (12 cases) or show macronodular or incomplete septal cirrhosis (30 cases), presumed to be of viral origin. The latter cases are more likely to have serum markers of current hepatitis B virus infection than those with evidence of alcohol abuse. We conclude that alcohol is increasing in importance as an etiologic association of hepatocellular carcinoma in urban South African Blacks. At the same time, the prevalence of macronodular cirrhosis (and of cirrhosis as a whole) in urban patients with this tumor has declined. The reason for this decline is not known.
Pattern and Prognosis of Liver Function Test Abnormalities During Parenteral Nutrition in Inflammatory Bowel Disease
Authors: Bengoa Jose M. , Hanauer Stephen B. , Sitrin Michael D. , Baker Alfred L. , Rosenberg Irwin H.
Published: March 2007

The pattern of liver function test abnormalities was examined during total parenteral nutrition (TPN), using both dextrose and fat emulsions as caloric sources, in 92 patients with inflammatory bowel disease. Seventy–two patients had completely normal tests before TPN while 20 had one or more abnormal liver function tests before TPN was started. Serum bilirubin levels were normal in all patients before TPN; within 2 weeks on TPN, 25% of patients had elevated bilirubin levels. Serum alkaline phosphatase rose to values above normal in 25% of patients with normal starting values but did not change in those with abnormal baseline liver function tests. Elevations of SGPT were characteristically more pronounced than were elevation of SGOT. After 2 weeks of TPN, mean serum SGOT rose from 15 to 26 IU per liter (p < 0.01) in patients with normal baseline values and from 28 to 50 IU per liter in those with abnormal baseline values. Elevations of serum SGPT were most common, affecting 25% of patients with normal baseline. The mean SGPT value rose from 13 to 38 IU per liter (p < 0.01) at 1 week of TPN. In patients with abnormal tests before TPN, the mean SGPT value rose from 45 to 102 IU per liter (p < 0.05). Liver biopsies performed in four patients with substantial elevations of aminotransferases revealed only minor nonspecific changes and no fatty infiltration. Elevated liver function tests promptly returned to baseline after TPN was discontinued, and progressive liver disease was not observed in any patient. Although abnormalities of liver function tests, particularly the aminotransferases, are common during balanced TPN in patients with inflammatory bowel disease, the favorable prognosis and benign histologic changes argue against the need to discontinue TPN in the presence of such changes.
Increased Portal Venous Resistance Hinders Portal Pressure Reduction During the Administration of β–Adrenergic Blocking Agents in A Portal Hypertensive Model
Authors: Kroeger Richard J. , Groszmann Roberto J.
Published: March 2007

We have recently shown that maintenance of portal hypertension in rats is highly dependent on high portal blood flow. This study attempts to determine whether portal hypertension, induced in the rat by partial constriction of the portal vein, can be reduced by lowering portal blood flow with a beta blocking agent. Portal hypertensive rats treated with propranolol had a reduction in portal blood flow to 0.89 ± 0.13 ml · min-1 · gm-1 accompanied by reduction in portal pressure to 12.6 ± 1.00 mm Hg, disproportionately small because of a rise in portal–collateral vascular resistance to 12.52 ± 1.63 dyne · sec · cm-5 · gm · 105 accompanying the portal blood flow reduction. Similarly, portal hypertensive rats receiving β–blockade with H35-25, an experimental β–blocker, demonstrated a 49% reduction in portal blood flow accompanied by only a 14% reduction in portal pressure, also disproportionately low because of a complicating 77% rise in portal–collateral vascular resistance. Normal rats were then given saline infusion to achieve similar blood flow elevations to that of portal hypertensive animals. Within a similar portal blood flow range of 0.76 ± 0.14 to 1.31 ± 0.07 ml · min-1 · gm-1, Portal hypertensive animals exhibited a significantly higher portal pressure range (12.6 ± 1.0 to 15.4 ± 0.4 mm Hg) than normals (8.9 ± 0.4 to 9.5 ± 0.4 mm Hg) largely due to a significantly higher range of portal resistance offered to portal blood flow by the portal–collateral bed of portal hypertensive rats (9.39 ± 0.25 to 16.63 ± 1.45 dyne · sec · cm-5 · gm · 105) in comparison with the portal venous system of normal animals (5.47 ± 0.70 to 10.00 ± 0.43 dyne · sec · cm-5 · gm · 105). We conclude that, in a hyperdynamic model of portal hypertension, the increase in portal pressure appears to be the result of combined elevations in portal blood flow and the portal vascular resistance to that flow. β–Blockade completely corrects the portal blood flow factor, but will be unable to adequately reduce portal pressure until the additional element of elevated portal vascular resistance can also be reduced.
The Sunnybrook Gallstone Study: A Double–Blind Controlled Trial of Chenodeoxycholic Acid for Gallstone Dissolution
Authors: Fisher Murray M. , Roberts Eve A. , Rosen Irvine E. , Shapero Theodore F. , Sutherland Lloyd R. , Davies Robert S. , Bacchus Raymond , Lee Victor S.
Published: March 2007

The Sunnybrook Gallstone Study was a randomized, double–blind, controlled trial of chenodeoxycholic acid treatment over 2 years in 160 patients with radiolucent gallstones. Sixty–four patients received 750 mg daily, 53 received 375 mg daily and 43 received placebo. Total dissolution of gallstones occurred in 10.9% of patients on 750 mg daily, 13.2% of those on 375 mg daily and in no patient on placebo. The drug was tolerated well. Diarrhea severe enough to cause withdrawal from the study occurred in two patients. No patient developed clinically significant hepatotoxicity. Serum cholesterol rose 10% or more above baseline after 2 years in 33% of patients treated with chenodeoxycholic acid and in 30% of those on placebo. Cholecystectomy was performed in 10.9% of patients on 750 mg daily, 17% on 375 mg daily and 13.6% on placebo. Chenodeoxycholic acid given at these doses dissolved radiolucent gallstones safely but the efficacy was limited.
Serum Bilirubins in Hepatobiliary Disease: Comparison With Other Liver Function Tests and Changes in the Postobstructive Period
Authors: Van Hootegem Philippe , Fevery Johan , Blanckaert Norbert
Published: March 2007

Unconjugated bilirubin and its mono– and diester conjugates were measured by alkaline methanolysis and normal–phase high–performance liquid chromatography (AMHPLC) in 195 serum specimens obtained from 63 patients with various hepatobiliary disorders and from 47 healthy adult controls. With this assay, esterified bilirubins were undetectable in the controls, and detection of esterified pigment in a sample was interpreted as an abnormal result. Using this criterion, the AMHPLC result in the clinical anicteric patients (n = 39) was more frequently abnormal (87%) than the corresponding value of fasting serum bile acids (48%), SGPT (52%), total bilirubins (55%), alkaline phosphatase (71%) or γ–glutamyl transpeptidase (71%). The cumulative frequency of abnormality of these tests was comparable to that of an abnormal AMHPLC result alone. All icteric patients had detectable esterified bilirubins as well as an increased alkaline phosphatase level, while a normal result was found for serum bile acids in 34%, for SGPT in 29% and for γ–glutamyl transpeptidase in 11%, respectively.

In most hyperbilirubinemic patients, total serum bilirubin levels, as determined by a conventional diazo method, exceeded the value obtained by AMHPLC. This discrepancy, which appears to reflect the presence of bilirubin covalently bound to serum protein, was particularly pronounced following desobstructive intervention in patients with obstructive jaundice, in whom the decline of serum bilirubins showed a fast and a slow disappearance component. The latter portion seemed to correspond with slow plasma clearance of bilirubin covalently linked to serum albumin, disappearing at a rate comparable to that of the albumin moiety.
Quantitative Analysis of Major, Minor and Trace Elements in Gallbladder Bile of Patients With and Without Gallstones
Authors: Harvey Robert C. , Taylor Dale , Petrunka Connie N. , Murray Andrew D. , Strasberg Steven M.
Published: March 2007

The concentration of 25 major, minor and trace elements in human bile was determined by inductively coupled plasma atomic emission spectrometry. Gallbladder bile was obtained during surgery from patients with cholesterol gallstones, pigment stones and with no biliary tract abnormalities (controls). Comparison of the concentration of elements (microgram per gram of solids) did not reveal any significant differences among the three patient groups. The in vitro nucleation time was not related to the concentration of any element measured.
Effect of Chronic Ethanol Ingestion on Hepatic and Intestinal Acyl Coenzyme A:Cholesterol Acyltransferase and 3–Hydroxy–3–Methylglutaryl Coenzyme A Reductase in the Rat
Authors: Field Jeffrey F. , Boydstun John S. , Labrecque Douglas R.
Published: March 2007

Two groups of rats were pair–fed diets in which 36% of the calories were provided by either ethanol or dextrimaltose. After 60 days on these liquid diets, rats fed ethanol were significantly smaller than control rats fed dextrimaltose. Serum cholesterol levels in ethanol–fed animals were 20% higher than control rats. Cholestasis was not observed histologically, and serum alkaline phosphatase and bilirubin levels were the same in both groups. The livers of animals ingesting ethanol accumulated triglycerides and cholesterol. The increase in cholesterol was due to an increase in cholesteryl esters. The cholesterol content of liver microsomes, however, was unchanged by ethanol feeding. A small increase in unesterified cholesterol was observed in intestinal micro–somes prepared from animals receiving ethanol. Microsomal fatty acids in liver and intestine were unchanged by the ethanol diet. Chronic ingestion of ethanol in these animals failed to change acyl coenzyme A:cholesterol acyltransferase or 3–hydroxy–3–methylglutaryl–coenzyme A reductase activities in the intestine. In contrast, the activities of acyl coenzyme A:cholesterol acyltransferase and 3–hydroxy–3–methylglutaryl–coenzyme A reductase were significantly increased in the livers of rats receiving ethanol. Thus, the chronic ingestion of ethanol caused a marked accumulation of hepatic cholesteryl esters. This was associated with a significant increase in the activities of enzymes that control the rates of both cholesterol synthesis and cholesterol esterification in the liver. These observed changes in enzyme activities may contribute to the lipid accumulation which occurs in these livers. Chronic ethanol consumption did not alter cholesterol metabolism in the intestine.
Experimental Laser Phototherapy of the Morris 7777 Hepatoma in the Rat
Authors: Holt Stephen , Tulip John , Hamilton Douglas , Cummins Judith , Fields Anthony , Dick Catherine
Published: March 2007

The tumoricidal effect of the activation of hematoporphyrin derivative (HpD), by an argon–ion–dye–laser (wavelength 630 nm), was investigated in the Buffalo rat bearing subcutaneous implants of the Morris 7777 hepatoma. Tumor growth was monitored by measuring the tumor volume with constant force callipers. In control animals and those that were pretreated with HpD alone (10 or 20 mg per kg by i.p. injection) or laser light alone (2,000 J at 100 mW), a predictable exponential growth pattern of the cancer was observed. Animals were pretreated with HpD (10 mg per kg by i.p. injection) 48 hr prior to the fiberoptic, intratumor delivery of laser radiation (2,000 J at 100 mW), when the tumor had reached a volume greater than 1.5 cm3. Forty–eight hours after combined laser and HpD treatment, the hepatoma underwent coagulation necrosis, and the tumor volume rapidly increased from a mean value of 1.8 ± 0.7 cm3 S.D. to a value of 5.8 ± 1.5 cm3 S.D., compared with a mean of 3.7 ± 0.7 cm3 S.D. in animals who had not received laser phototherapy. Rats treated with HpD and laser light survived longer (mean survival time 48 ± 12 days S.D.) than did the other animals treated with the laser alone or HpD alone (mean survival time 31 S± 16.5 S.D.). Tissue biodistribution studies with tritiated hematoporphyrin derivative, given with doses of 10 and 20 mg per kg of HpD, showed higher concentrations of the dye in the liver, kidneys and spleen than in the tumor at 48 hr after administration of the dye. The ratio of uptake of HpD between the Morris 7777 hepatoma and adjacent muscle was approximately 2:1 in both dose ranges of the dye, implying that HpD does not localize in malignant tissue in a preferential manner. Laser phototherapy with HpD significantly interrupts the growth of the highly malignant Morris 7777 hepatoma and prolongs the survival time of Buffalo rats bearing this neoplasm.
Epidemiology and Clinical Impact of Hepatitis D Virus (Delta) Infection
Authors: Jacobson Ira M. , Dienstag Jules L. , Werner Barbara G. , Brettler Doreen B. , Levine Peter H. , Mushahwar Isa K.
Published: March 2007

We tested sera collected between 1976 and 1984 from 362 persons in a variety of epidemiologic categories with acute and chronic hepatitis B and from 76 hemophiliacs and drug addicts with hepatitis B antibodies for hepatitis D markers. Hepatitis D markers were common in hemophiliacs, drug addicts, Afghanistanis, prisoners and hemodialysis patients; rare in persons from other hepatitis–B endemic areas, persons with sporadic hepatitis B and homosexual men; and absent in health–care workers and institutionalized mentally retarded persons. No change was observed in the frequency of this infection during the 9 years of this study. We found hepatitis D markers in 5% of patients with acute hepatitis B, 1 of 3 with fulminant hepatitis and in 4 (1 in a homosexual male) of 12 episodes of acute hepatitis in hepatitis B carriers. Hepatitis D markers were more frequent in chronic liver disease (18%) than in asymptomatic hepatitis B carriage (2%), but there was no association between severity of chronic hepatitis and hepatitis D. These findings indicate that, to date, health–care workers and institutionalized mentally retarded persons have been spared from infection with this agent but suggest that homosexual males may not continue to be spared. Even in an area nonendemic for hepatitis D, this agent contributed to 20 to 30% of chronic hepatitis B and acute hepatitis superimposed on chronic hepatitis B infection.
Long–Term Maintenance of Taurocholate Uptake by Adult Rat Hepatocytes Co–Cultured With A Liver Epithelial Cell Line
Authors: Foliot Armelle , Glaise Denise , Erlinger Serge , Guguen-Guillouzo Christiane
Published: March 2007

Taurocholate (TC) uptake by adult rat hepatocytes co–cultured with other rat liver epithelial cells (RLEC) was studied comparatively to hepatocytes in primary culture. Cells were cultured on Petri dishes for desired times prior to measuring their ability to transport TC. TC uptake was linear for 150 sec in both culture conditions. In hepatocytes cultured alone, the initial rate of TC uptake at an extracellular concentration of 100 μ M was 0.19 ± 0.02 nmole per min per 106 cells after 48 hr of culture and decreased by 75% after 4 to 6 days. In hepatocytes co–cultured with RLEC, the rate of uptake at 48 hr (0.31 ± 0.01 nmole per min per 106 cells) was significantly higher than in hepatocytes cultured alone (p < 0.01); in addition, TC uptake remained stable at an average rate of 0.17 ± 0.01 nmole per min per 106 cells for up to 56 days. No detectable uptake was found in RLEC cultured alone. TC uptake exhibited both saturable (Vmax = 0.30 ± 0.03 nmole per min per 106 cells and Km = 42.6 ± 4.4 μM) and nonsaturable components. These kinetic parameters were similar to those previously reported in isolated hepatocytes and in short–term cultured hepatocytes. TC uptake exhibited sodium dependence and was significantly reduced when extracellular sodium was replaced by lithium and sucrose, or in the presence of 1 mM ouabain. After 18 days of co–culture, TC uptake had qualitatively the same characteristics as at 48 hr, with a saturable and a nonsaturable component.

These findings strongly support the view that the sodium–dependent bile acid uptake system present in normal hepatocytes was maintained in the co–culture system as previously reported for other liver–specific functions.
Androgen and Estrogen Response to Adrenal and Gonadal Stimulation in Idiopathic Hemochromatosis: Evidence for Decreased Estrogen Formation
Authors: Kley Hans K. , Stremmel Wolfgang , Niederau Claus , Hehrmann Rainer , Shams Omar , Strohmeyer Georg , Krüskemper Hans L.
Published: March 2007

Gonadal function in idiopathic hemochromatosis (IHC) was evaluated by comparing clinical features and levels of sex hormones in 10 male patients with IHC (cirrhosis, 4; fibrosis, 6), 6 male patients with alcoholic cirrhosis (AC) and 10 healthy, age–matched controls. Impotence was present in 9 IHC and all AC patients and was associated with decreased plasma testosterone levels. However, gynecomastia, a feature in all patients with AC, was not present in IHC, and plasma sex hormone binding globulin was normal. Patients with IHC showed significantly lower basal estradiol levels (17.7 ± 6.3 pg per ml) than did controls (28.5 ± 8.5 pg per ml), and low LH levels (p < 0.01), which were insufficiently stimulated by luteinizing hormone releasing hormone (n = 8) as well as a decrease in prolactin concentration (2.9 ± 1.4 vs. 5.9 ± 1.9 ng per ml in the controls) suggesting pituitary failure. Synthesizing capacity of sex hormones was determined by adrenocorticotropic hormone and human chorionic gonadotropin administration. Basal and stimulated levels of andro–stenedione and cortisol indicated normal function of the adrenals in IHC. However after adrenocorticotropic hormone, estrone levels increased to only 16.2 ± 8.4 pg per ml (controls, 27.3 ± 4.7 pg per ml; p < 0.01). Increments of estrone (12.5 ± 9.2 pg per ml) and estradiol (17.9 ± 11.6 pg per ml) were also lower in IHC following human chorionic gonadotropin administration than in controls (26.0 ± 7.2 and 37.5 ± 11.4 pg per ml, respectively). In contrast, plasma human chorionic gonadotropin raised testosterone levels 3.3–fold in IHC and 2.2–fold in controls. Basal and stimulated levels of testosterone, estrone and estradiol were lower in IHC patients with cirrhosis than fibrosis. Normal estrogen levels in IHC may be due to “normal” conversion from androgens to estrogens, as occurred for androstenedione in four patients with IHC.

In patients with AC, reduced levels of plasma testosterone were associated with increased luteinizing hormone; androstenedione and estrogens were elevated and rose higher after adrenocorticotropic hormone or human chorionic gonadotropin stimulation. High estrogen activity was paralleled by elevated sex hormone binding globulin, and an increase in plasma prolactin.

These findings suggest low estrogen activity in IHC, which appears to correlate with the severity of liver damage. These features are in contrast to AC, where increased conversion of androgens to estrogens was established previously.
Ascitic Fluid Chemical Analysis Before, During and After Spontaneous Bacterial Peritonitis
Authors: Runyon Bruce A. , Hoefs John C.
Published: March 2007

A retrospective analysis of 22 patients whose ascitic fluid had been analyzed prior to the onset of spontaneous bacterial peritonitis, during infection and/or after treatment of peritonitis revealed that neither the ascitic fluid total protein nor the absolute ascitic fluid glucose changed during the infection or after treatment of the infection although the ascitic fluid/serum glucose ratio did decrease (p < 0.001) with infection. The ascitic fluid lactate dehydrogenase increased significantly (p < 0.05) during infection compared to the baseline value. Contrary to the typical findings in infected body fluids, the total protein content and absolute glucose content of “spontaneously” infected ascitic fluid do not measurably change.
Decreased Serum Group–Specific Component Protein Levels and Complexes With Actin in Fulminant Hepatic Necrosis
Authors: Lee William M. , Emerson David L. , Werner Phillip A.M. , Arnaud Philippe , Goldschmidt-Clermont Pascal , Galbraith Robert M.
Published: March 2007

Monomeric G–actin has recently been shown to form high–affinity complexes with group–specific component protein (Gc), and this process might be expected to occur in vivo when hepatocyte necrosis with release of actin takes place. We therefore measured serum Gc levels and searched for evidence of actin–containing complexes of Gc in 147 sera from 21 normal subjects and 126 patients with acute and chronic liver diseases. Sera were examined for Gc concentration using an ELISA with purified Gc as standard. Gc levels were greatly diminished (<10 mg per dl) in 5 of 37 patients with acute hepatitis and 1 of 3 patients with subacute hepatic necrosis, and the mean values for these groups overall as well as those for chronic active hepatitis patients were significantly less than that observed in the normal controls (mean, 35.5 mg per dl). No significant alteration in Gc level was observed in the chronic disease categories studied. In contrast, Gc concentrations < 10 mg per dl were found in 12 of 14 patients with fulminant hepatic necrosis, and the mean for this group (9.7) was significantly reduced (p < 0.001). Sequential studies in 12 patients with acute hepatitis of moderate to marked severity but without a fulminant phase showed significant diminutions in initial Gc levels when these were compared with Gc levels obtained during recovery. Using analytical isoclectric focusing with print immunofixation, variable amounts of Gc:G–actin complexes could be demonstrated in virtually all sera examined, but the proportion of total Gc present as complex with G–actin appeared greater in fulminant hepatic necrosis sera. The marked reduction of serum Gc levels in fulminant hepatic necrosis is likely due in part to decreased hepatic synthesis of Gc; however, the increase in Gc:G–actin complexes may also affect Gc levels. These findings support the hypothesis that Gc, in binding to G–actin, may function to maintain homeostasis in situations of massive actin release.
Human Hepatoma–Associated Cell Surface Antigen: Identification and Characterization by Means of Monoclonal Antibodies
Authors: Shouval Daniel , Eilat Dan , Carlson Rolf I. , Adler Ruth , Livni Nelly , Wands Jack R.
Published: March 2007

A library of murine monoclonal antibodies reactive with human hepatoma cells was generated following immunization of Balb/c mice with an intact cloned human hepatoma cell line, designated PLC/PRF/5–NR. We report the characterization of one such IgG2a antibody, designated anti–PLC1. This antibody specifically stains parental PLC/PRF/5 cell membranes and membranes of SK–Hep 1 and Mahlavu human hepatoma cells grown in culture, using indirect immunofluorescence and horseradish immunoperoxidase techniques. A similar pattern of membranous staining was observed in solid tumors derived from the three hepatoma cell lines which were injected subcutaneously into athymic nude rats and mice. Spontaneous capping on the cell surface was observed in 7 to 30% of the three human hepatocellular carcinoma cell types when incubated in suspension with monoclonal anti–PLC1 at 37°C. Treatment of cells with trypsin or sustained growth in culture did not affect the intensity of membranous staining. Monoclonal anti–PLC1 appeared specific, and antibodies did not stain a variety of human carcinoma cell lines and primary tumors of nonhepatic origin, or several normal human and murine tissues. Purified 125I–labeled monoclonal anti–PLC1 bound specifically to the three hepatoma cell lines in culture. Specificity of the antigen–antibody reaction was demonstrated by competitive binding inhibition in experiments using unlabeled homologous antibody. Binding of 125I–anti–PLC1 was not inhibited by unlabeled monoclonal antibodies to HBsAg or to α–fetoprotein. Two hepatoma cell lines secrete a protein that specifically blocks binding of 125I–anti–PLC1 antibodies to cell surface antigenic determinants. This “hepatomaassociated” protein was subsequently purified by affinity chromatography from supernates derived from the three hepatoma cell lines. Analysis of this protein by sodium dodecyl sulfate–polyacrylamide gel electrophoresis under reducing conditions revealed a major protein band at 70 to 75 kd. These findings suggest that monoclonal antibodies such as anti–PLC1 may serve as a potential reagent for serodiagnosis, histologic identification, imaging and destruction of human hepatocellular carcinoma.
Suppression of T Helper Function: An Immunoregulatory Effect of Rosette Inhibitory Factor in Hepatitis B Virus Infection
Authors: Sanders Gary E. , Perrillo Robert P.
Published: March 2007

The potential immunoregulatory effects of rosette inhibitory factor (RIF) were evaluated using lymphocyte subpopulations defined by monoclonal antibodies (OKT4, OKT8). Initial experiments indicated that RIF inhibits E–rosette formation by T cells that provide helper/inducer function (OKT4+). Subsequently, experiments were done to assess if RIF had an inhibitory effect on in vitro immunoglobulin and anti–HBs production. These studies used peripheral blood mononuclear cells from convalescent and hepatitis B–vaccinated donors. The results indicated that RIF–positive lowdensity lipoprotein, but not RIF–negative low–density lipoprotein, inhibits in vitro production of IgG and IgM by 60 to 70% and totally ablates anti–HBs synthesis. In order to determine if RIF directly affected the proliferative response of T4 lymphocytes, these cells were cultured in the presence of optimal mitogen concentrations and either RIF–positive or RIF–negative low–density lipoprotein. The experiments demonstrated that RIF–treated T4 cells are hyporesponsive to pokeweed mitogen and phytohemagglutinin when compared to T4 cells cultured in the absence of RIF. In contrast, B cell proliferation in response to soluble T helper factors was not affected by incubation with RIF. As the production of soluble helper factors by T4 cells was inhibited by exposure to RIF–positive but not RIF–negative low–density lipoprotein, we conclude that the suppressive effect of RIF on immunoglobulin and anti–HBs synthesis is due to inhibition of this specific helper T cell function.
Sinusoidal Caliber in Alcoholic and Nonalcoholic Liver Disease: Diagnostic and Pathogenic Implications
Authors: Vidins Eva I. , Britton Robert S. , Medline Alan , Blendis Laurence M. , Israel Yedy , Orrego Hector
Published: March 2007

Portal hypertension in alcoholic liver disease has been attributed to an increased resistance to blood flow either of sinusoidal or of postsinusoidal origin. The former should be accompanied by sinusoidal compression while the latter is expected to result in an increased or a normal sinusoidal diameter. Patients with alcoholic liver disease showed a marked reduction (p < 0.001) in relative sinusoidal area (995 ± 135 μm2; n = 19) when compared to nonalcoholic patients with normal liver histology (5, 100 ± 389 μm2; n = 6), or to patients with nonalcoholic liver disease (6, 242 ± 467 μm2; n = 19). Hepatocyte surface area was significantly increased in patients with alcoholic liver disease when compared to hepatocytes from normal biopsies (563 ± 32 μm2 vs. 301 ± 26 μm2; p < 0.001). Patients with nonalcoholic liver disease had hepatocyte surface areas within the normal range (327 ± 14 μm2). There was a significant inverse correlation between hepatocyte size and sinusoidal area (r = -0.63; p < 10-6; n = 44), indicating that larger hepatocytes were associated with sinusoidal compression. In the alcoholic patients, portal pressure correlated inversely (r = -0.77; p < 0.01) with sinusoidal area only after the sinusoidal area was markedly reduced to areas below 20% of normal. Such a threshold was not reached in patients with nonalcoholic liver disease, in whom no correlation between sinusoidal area and portal pressure was observed. Rats fed chronically with a diet containing 35% of calories as ethanol, in which liver enlargements of 36 to 42% were observed relative to controls fed an isocaloric carbohydrate diet, had a significant reduction in both extracellular space and blood space per unit liver weight. Data presented support the hypothesis that hepatocyte expansion and compression of the sinusoidal space appear to be important determinants in the development of portal hypertension in alcoholic liver disease. In addition, the striking difference in the observable sinusoids in alcoholic and nonalcoholic liver disease should provide an added criterion in the histological differentiation of the two conditions.
The Effect of the Combination of Nitroglycerin and Propranolol on Splanchnic and Systemic Hemodynamics in A Portal Hypertensive Rat Model
Authors: Kroeger Richard J. , Groszmann Roberto J.
Published: March 2007

Present investigations support major contributions from increases in both portal blood flow and portal vascular resistance in the mechanism that maintains portal hypertension. β–Adrenergic blockers have been shown to reduce the elevated portal blood flow component. The possibility that nitroglycerin administration could reduce the elevated portal vascular resistance component is investigated here. Portal hypertension was induced in rats by a calibrated constriction of the portal vein. Portal hypertensive rats receiving placebo exhibited significant (p < 0.05) elevations over normal rats receiving placebo in cardiac index, portal venous inflow and portal pressure. Portal hypertensive rats were then divided into groups receiving nitroglycerin infusion, propranolol (β–adrenergic blockade) and combined administration of nitroglycerin and propranolol. Significant reductions (p < 0.05) in portal blood flow of 30, 32 and 44%, respectively, were accompanied by significant portal pressure reductions of 2.7 ± 0.2, 1.7 ± 0.3 and 3.6 ± 0.4 mm Hg in all groups, respectively (p < 0.05). Nitroglycerin failed to prevent a 46% rise in portal–collateral resistance accompanying the portal blood flow reduction, similar to resistance rises also found in propranolol–treated (33%) and combination nitroglycerin–propranolol–treated (49%) groups. We conclude that nitroglycerin infusion can significantly reduce portal pressure, alone or in combination with β–blockade, by reducing portal venous inflow. It appears that nitroglycerin reduces portal blood flow through the effect of baroreceptor sympathetic reflexes that constrict the splanchnic bed in response to vasodilatation and venous pooling.
Three–Dimensional Observations of the Hepatic Arterial Terminations in Rat, Hamster and Human Liver by Scanning Electron Microscopy of Microvascular Casts
Authors: Yamamoto Kazuhide , Sherman Igor , Phillips James M. , Fisher Murray M.
Published: March 2007

The arterial terminations were studied by scanning electron microscopy of microvascular casts in rat, hamster and human livers. Important species differences were observed. In the rat, frequent anastomoses between the terminal hepatic arterioles and portal venules were observed, whereas a few arterioles terminated directly into sinusoids. On the contrary, no arterioportal venous anastomoses were demonstrated in the hamster and human livers. In these latter species, all arterioles terminated into sinusoids adjacent to the portal tracts. No intralobular arterioles were observed in any species.
Effect of Chronic Ethanol Administration on Enzyme and Lipid Properties of Liver Plasma Membranes in Long and Short Sleep Mice
Authors: Zysset Thomas , Polokoff Mark A. , Simon Francis R.
Published: March 2007

Mechanisms of alcoholic liver disease are still ill defined. We evaluated in two outbred lines of mice whether chronic ingestion of ethanol alters the lipid composition and/or enzyme activity of liver plasma membranes. Two mouse lines with different sensitivities towards the hypnotic effect of ethanol, designated long sleep and short sleep, were fed a liquid diet containing ethanol for 30 days. Ethanol intake reached 30 gm per kg per day in both lines, and serum ethanol levels were similar. In addition, hepatic triglyceride levels were similarly increased 2–fold with ethanol feeding. The following effects of ethanol treatment were observed in liver plasma membrane fractions: (i) Na+, K+–ATPase was significantly increased to 26% above control in long sleep only; (ii) alkaline phosphatase activity was 2–fold increased in both lines; (iii) 5′–nucleotidase, leucine aminopeptidase and Mg2+–ATPase activities remained unchanged in both lines; (iv) unesterified cholesterol and total phospholipid contents were unaltered in both lines, and (v) cholesteryl esters were increased in both lines, but to a greater extent in short sleep (1.5 vs. 4–fold). Thus, chronic ethanol ingestion induces specific alterations in liver plasma membrane structure and function, suggesting that adaptive responses to ethanol may be determined in part by inherited factors.
Liver Disease Activity and Hepatitis B Virus Replication in Chronic Delta Antigen–Positive Hepatitis B Virus Carriers
Authors: Hadziyannis Stephanos J. , Sherman Morris , Lieberman Harvey M. , Shafritz David A.
Published: March 2007

Delta antigen is currently thought to reflect superinfection of the liver with a defective RNA virus (delta agent), requiring helper function from hepatitis B virus for its replication. To assess the influence of delta agent on hepatitis B virus replication in patients persistently infected with both viruses and showing chronic liver disease, we measured serum and liver hepatitis B virus DNA in HBsAg–positive chronic liver disease patients who were either positive or negative for delta antigen in the liver. Hepatitis B virus DNA was assayed in the serum of 21 patients with delta antigen–positive/HBsAg–positive chronic liver disease and in 21 patients with delta antigen–negative/HBsAg–positive chronic liver disease matched for HBeAg/anti–HBe status and underlying liver histology. HBcAg and delta antigen in liver was determined by immunofluorescence or immunoperoxidase staining. In delta antigen–positive/HBsAg–positive chronic liver disease, serum hepatitis B virus DNA was detected transiently in 4 of 21 cases (19%) and was present in these patients at low levels (trace to 2+). In contrast, 9 of 21 (43%) delta antigen–negative/HBsAg–positive chronic liver disease patients were serum hepatitis B virus DNA positive, and five of these had high serum hepatitis B virus DNA levels (3+ to 4+). Serum HBsAg and anti–HBc titers were significantly lower in delta antigen–positive cases and correlated with reduced amount of HBcAg in the liver. There was a reduction in the proportion of delta antigen–positive/HBsAg–positive carriers showing virion or replicating hepatitis B virus DNA forms in the liver (2 of 13), as compared to liver hepatitis B virus DNA in delta antigen–negative/HBsAg–positive carriers (9 of 12). These findings indicate that in delta antigen–positive chronic hepatitis, synthesis of hepatitis B virus genomes and gene products remain suppressed, whereas production of delta components continues at high levels. These observations may be of value in understanding the pathobiology of chronic delta antigen infection and suggest that liver disease activity in delta antigen–positive/HBsAg–positive carriers is more related to persistent delta infection than to continued hepatitis B virus replication.
Recombinant Leukocyte Interferon Treatment of Chronic Hepatitis B
Authors: Dusheiko Geoffrey , Dibisceglie Adrian , Bowyer Sheila , Sachs Evelyn , Ritchie Marian , Schoub Barry , Kew Michael
Published: March 2007

We have investigated the efficacy of a relatively prolonged course of recombinant leukocyte interferon treatment in 14 chronic HBsAg–, HBeAg–, hepatitis B virus DNA– and DNA polymerase–positive carriers. α–Interferon was administered for 9 weeks. Six of 14 treated carriers have a sustained loss of HBeAg, hepatitis B virus DNA and DNA polymerase. Four subsequently lost HBsAg (28.5%). Elevated pretreatment SGPT concentrations, histologic chronic active hepatitis, an exacerbation of chronic hepatitis with an increase in SGPT concentrations in the last weeks of treatment and possibly recent onset of the carrier state was associated with complete inhibition of viral replication. None of 11 matched, untreated HBsAg–, HBeAg–, hepatitis B virus DNA– and DNA polymerase–positive carriers monitored during the same period lost HBsAg. The effect of recombinant leukocyte interferon may require an appropriate host–immune response. The efficacy of recombinant leukocyte interferon therapy is restricted, but it may be of benefit in a proportion of carriers, if these carriers can be precisely identified.
Effects of Ioglycamide on the Hepatic Transport of Bilirubin and Its Mono– and Diconjugates in the Rat
Authors: Mesa Vital A. , Fevery Johan , Heirwegh Karel P.M. , De Groote Jan
Published: March 2007

Bilirubin seems to share the biliary excretion pathway with other organic anions, but not with bile acids. We studied the effects of the organic anion ioglycamide, an iodinated contrast agent, on bilirubin metabolism in Wistar rats. This compound does not undergo conjugation and is characterized by a maximal biliary secretory rate (Tm). The results show that in spite of producing a 3–fold increase in bile flow, ioglycamide excretion under Tm conditions decreased the output of unconjugated bilirubin and its monoconjugate by approximately 90%. Diconjugated bilirubin decreased by only 50% and became by far the predominant pigment in bile (86.5 ± 6.0% of total pigment vs. 61.0 ± 4.0% in basal conditions, n = 12). Unconjugated and monoconjugated bilirubins changed in parallel suggesting that the former arises from the monoconjugates. In serum, dicon–jugated bilirubin augmented from trace amounts to 1.15 ± 0.17 μmole per liter. Total conjugated pigments in serum increased from 5 to 85% of total bilirubin.

Bile acid output remained unchanged. Pretreatment of rats with ioglycamide altered neither the activity of bilirubin UDP–glucuronyltransferase nor the ratio of diconjugate to monoconjugate formed at both low (25 μM) and high (164 μM) bilirubin concentrations. The observed biological effects of ioglycamide were dose–dependent and fully reversible. We suggest that ioglycamide interferes with the excretion of conjugated bilirubins (“bilirubinostasis”). The monoconjugates retained in the hepatocyte might then undergo more efficient transformation to diconjugates, the latter thus becoming the most important bile pigments in serum and bile.
The Effect of Glutathione Depletion on 14Co2 Evolution From [14C] Methyl–Labeled Aminopyrine in Intact Rats
Authors: Bhatt Harshika S. , Combes Burton
Published: March 2007

The effect of hepatic glutathione depletion on 14CO2 evolution from [14C]methyl–labeled aminopyrine was assessed in fed male Sprague–Dawley rats. Within 30 min of i.p. administration of either diethylmaleate or phorone, hepatic glutathione fell approximately 75 to 80% and remained depressed for the ensuing 120 min. [14C]Aminopyrine was i.p. administered 30 min after the glutathione–lowering agents (zero time) and exhaled 14CO2 was collected at 15–min intervals for the next 120 min. Parameters of 14CO2 exhalation including peak exhalation rate, cumulative exhalation from 0 to 120 min and the elimination rate constant were all impaired in glutathionedepleted rats. Metabolism of the [14C]methyl groups involves N–demethylation with formation of formaldehyde, oxidation to formate and conversion to 14CO2. Glutathione depletion did not affect CO2 evolution from i.p. administered formate or bicarbonate. The glutathione–dependent step presumably involves either or both generation of formaldehyde or its subsequent oxidation to formate.
Recovery of Liver Function in Partially Hepatectomized Rats Evaluated by Aminopyrine Demethylation Capacity
Authors: Sendama I. , de Hemptinne B. , Lambotte L.
Published: March 2007

Aminopyrine demethylation was investigated in rats after a 70% hepatectomy to assess possible parallelism between the recovery of mass and function. Tests were performed by analyzing 14CO2 exhalation from 0.1 μCi per 100 gm of body weight of [dimethylamine–14C]aminopyrine given intraperitoneally with incremental doses of unlabeled drug.

Early after 70% hepatectomy, Vmax was reduced by 52%. This discordance between mass and function was not due to extrahepatic aminopyrine demethylation, since liver exclusion reduced demethylation of aminopyrine to nearly nil. Whether it results from increased liver blood flow in the remnant liver is less clear: portacaval anastomosis provoked an identical fall in Vmax and liver blood flow, but aortal–portal fistula which increased liver blood flow by 70% did not modify Vmax, The early increase in Vmax could be related to a “hepatotrophic” factor of splanchnic origin which increased after partial hepatectomy and decreased after portacaval shunt.

After the early period, Vmax, expressed per gram of actual liver weight, returned to control range. Throughout regeneration (4 to 144 hr), no modification was observed in Km nor in cytochrome P–450 concentration. Enzymatic induction with phenobarbital increased the demethylation capacity more than liver weight in intact and regenerating liver. Except for the first hours after partial hepatectomy or after enzymatic induction, the aminopyrine demethylation capacity directly correlated with liver mass and may be useful in evaluating liver regeneration in vivo.
Acute and Chronic Changes in the Microcirculation of the Liver in Inbred Strains of Mice Following Infection With Mouse Hepatitis Virus Type 3
Authors: Macphee Peggy J. , Dindzans Vincent J. , Fung Lai-Sum , Levy Gary A.
Published: March 2007

The acute and chronic effects of mouse hepatitis virus type 3 on the microcirculation of the liver in both semisusceptible C3HeB/FeJ and fully resistant A/J mice were studied. In the C3HeB/FeJ mice, abnormalities of microcirculatory flow were noted as early as 12 hr after infection and by 24 hr, localized avascular foci appeared. Disturbances were characterized by granular blood flow, sinusoidal microthrombi, distortion of sinusoids by edematous hepatocytes and necrotic lesions. Following the acute infection, Day 10, two patterns of chronic disease were observed. Eighty percent of the mice developed chronic granulomatous hepatitis whereas in the remaining 20% a more severe chronic aggressive hepatitis was observed which was characterized by ongoing hepatocellular necrosis and a marked mononuclear cell infiltrate. In both cases, in vivo microcirculatory abnormalities were found predominantly around visible lesions. Onset of the microcirculatory abnormalities was found to be concomitant with a rise in monocyte related procoagulant activity. Procoagulant activity rose acutely and remained elevated throughout the chronic phase but was higher in animals with severe disease. In contrast to the above, normal blood flow and histology were seen in the resistant A/J mice at all times following infection, and procoagulant activity remained at basal levels despite active viral replication as demonstrated by immunofluorescence studies and recovery of infectious virus. These observations suggest a role for monocyte procoagulant activity in the development of microcirculatory abnormalities following mouse hepatitis virus type 3 infection which may be important in the pathogenesis of the disease.
Production of Two Distinct and Independent Hepatic Immunoregulatory Molecules by the Perfused Rat Liver
Authors: Chisari Francis V. , Nakamura Mary , Milich David R. , Han Keith , Molden Daniel , Leroux-Roels Geert G.
Published: March 2007

By manipulating dietary sugar intake and perfusate glucose concentration, we have identified two independent hepatic immunoregulatory molecules produced by the perfused rat liver. The first is released by injured hepatocytes, appears in perfusates together with hepatocellular glutamic pyruvic transaminase, is quantitatively inhibited by exogenous L–arginine and coelutes with arginase on high–pressure liquid chromatography. Based on these findings, we conclude that this activity is due to the release of cytoplasmic arginase from injured hepatocytes. Since supplementation studies reveal that lymphocyte proliferation is exquisitely arginine–dependent, it is conceivable that arginase released by injured hepatocytes might influence lymphocyte functionin vivoby local arginine depletion. The second immunoregulatory molecule is released by noninjured hepatocytes following induction by sugar, particularly glucose, bothin vivoorin vitro. This inducible activity is arginase–independent, triglyceride–rich and floats at a density less than 1.006 gm per ml upon ultracentrifugation. Based on these characteristics, we tentatively ascribe this activity to hepatic very low density lipoprotein, the serum counterpart of which is known to express many immunoregulatory properties. These results directly illustrate for the first time the pathophysiological conditions required for the secretion and release of these distinct and independent hepatic immunoregulatory molecules, and they suggest possible routes by which they may influence immunological homeostasis and immunologically mediated liver disease.