bluuebunny/crossref_metadata_2025 huggingface dataset:
The pathology of hepatitis C as a function of mode of transmission: Blood transfusion vs. Intravenous drug use
Authors: Gordon Stuart C. , Elloway Richard S. , Long John C. , Dmuchowski Carl F.
Published: March 2007

We reviewed the clinical records of 140 consecutively evaluated patients with chronic hepatitis C infection. One hundred twenty-four patients (89%) contracted infection through blood transfusion or intravenous drug use. The liver biopsy specimens of 83 patients (43 blood transfusion cases and 40 intravenous drug abuse cases) were examined without knowledge of the mode of disease transmission. The mean histological activity index score was significantly higher in the blood transfusion group (10.2 ± 4.2) than in the intravenous drug use group (6.9 ± 4.5) (p = 0.001). The transfusion group had more periportal bridging necrosis (p = 0.0015) and fibrosis (p = 0.0016) than did the intravenous drug use group, whereas significant differences between lobular degeneration and portal inflammation were not achieved across the two groups. The distribution of final biopsy interpretations also differed significantly between the two groups (p < 0.001), with chronic active hepatitis more frequent in the transfusion group. Moreover, lymphoid aggregates and bile duct damage were more common in patients with chronic hepatitis due to blood transfusion. Multivariate analysis showed that the mode of viral transmission was the most powerful predictor of histological activity index score when tested against patient gender, duration of disease or age at biopsy. One year after completion of this study, 9 of 70 transfused patients and 1 of 54 intravenous drug users had died of liver disease or are awaiting liver transplantation at this writing (p = 0.03). We conclude that transfusion-acquired hepatitis C is associated with more aggressive histological inflammatory activity than hepatitis resulting from intravenous drug use. We postulate that the severity of the initial pathological lesion predicts histological disease activity. (HEPATOLOGY 1993;18:1338-1343.)
Activation of the fibrinolytic system in patients with fulminant liver failure
Authors: Pernambuco Ricardo J.B. , Langley Peter G. , Hughes Robin D. , Izumi Satoru , Williams Roger
Published: March 2007

Abnormalities of blood coagulation and fibrinolysis are a major part of fulminant liver failure. In this study, the key components of the fibrinolytic system were determined in 42 patients with this condition. Admission levels of plasma plasminogen activity were low (9.1% of normal), as to a lesser extent were the activities of its inhibitors α2-antiplasmin (20.5% of normal) and C1 inhibitor (64% of normal). Tissue plasminogen activator activity was found at normal levels, whereas the level of its fast inhibitor, plasminogen activator inhibitor-1, was greatly increased compared with that of controls (24.3 U/ml and 7.4 U/ml, respectively), indicating a shift toward inhibition of fibrinolysis in these patients. Thrombin-antithrombin complex levels in plasma were significantly increased in fulminant liver failure compared with those in controls (33.5 μg/L vs. 2.5 μg/L, p < 0.001), indicating activation of coagulation in these patients. High plasma levels of D-dimer, a fragment of cross-linked fibrin, were also found (1,510 μg/L vs. 33 μg/L in controls, p < 0.001); this finding correlated with the increased level of thrombin-antithrombin complex (r = 0.61, p < 0.001), consistent with activation of fibrinolysis resulting from intravascular coagulation. In conclusion, there are gross abnormalities of the fibrinolytic system in fulminant liver failure, but because inhibitory activity appears to be present in adequate quantities, this limits the incidence of bleeding due to fibrinolysis. (HEPATOLOGY 1993;18:1350-1356.)
Preneoplastic significance of hepatic iron-free foci in genetic hemochromatosis: A study of 185 patients
Authors: Deugnier Yves M. , Charalambous Paul , Quilleuc Daniéle Le , Turlin Bruno , Searle Jeffrey , Brissot Pierre , Powell Lawrie W. , Halliday June W.
Published: March 2007

Sublobular nodules of hepatocytes free of iron or exhibiting much less iron than the surrounding parenchyma, referred to in this study as iron-free-foci, are frequently found in the livers of patients with genetic hemochromatosis complicated by hepatocellular carcinoma. To test the hypothesis that such nodules are preneoplastic lesions, iron-free foci were sought in the initial liver biopsy specimens of 185 patients with untreated and uncomplicated genetic hemochromatosis. Iron-free foci were found in 14 (7.6%) patients, all men, aged from 38 to 76 yr, with heavy iron overload and with fibrosis or cirrhosis. Twelve patients with iron-free foci were followed for 0.9 to 15 yr (7 ± 6 yr). In six (50%), HCC developed, compared with 2 (8%) from a control group consisting of 24 patients without IFF matched according to age, sex, degree of fibrosis, liver iron amount and follow-up duration. The mean number of iron-free foci per iron-free foci-positive specimen was 3.2 ± 2.1. Ten patients had dysplastic aspects in their iron-free foci, and four had intrahepatocytic iron-positive inclusions at the periphery of iron-free foci. Proliferative cell nuclear antigen was positive in 75% of iron-free foci and in 24% ± 21% of hepatocyte nuclei in iron-free foci. This study clearly demonstrates that iron-free foci are proliferative lesions and strongly suggests that such nodules are preneoplastic foci. Therefore the finding of IFF in the initial liver biopsy specimen from a patient with genetic hemochromatosis should lead to regular screening for hepatocellular carcinoma. (HEPATOLOGY 1993;18:1363-1369.)
The role of transjugular liver biopsy in fulminant liver failure: Relation to other prognostic indicators
Authors: Donaldson Bruce W. , Gopinath Ramya , Wanless Ian R. , Phillips James M. , Cameron Ross , Roberts Eve A. , Greig Paul D. , Levy Gary , Blendis Laurence M.
Published: March 2007

Early and accurate diagnosis and prognosis of patients with fulminant liver failure is of critical importance for optimum management. We investigated the role of transjugular liver biopsy in the management of patients with fulminant liver failure and assessed its value in comparison with the recently proposed King’s College criteria. Sixty-one patients with fulminant liver failure, ages 2 to 82 yr, were retrospectively analyzed. The main outcome measures were survival vs. death or progression to orthotopic liver transplantation. Transjugular liver biopsy was successful in 60 of 61 patients, with a mean core tissue length of 2.1 cm. There were eight minor complications, all of which were managed conservatively. Biopsy specimens were evaluated for degree of fibrosis, percentage of hepatocellular necrosis and presence of bile duct proliferation, hepatocellular mitotic figures and binucleate hepatocytes for each of the 54 specimens available for analysis. In 34 of 54 patients (63%), the presumed clinical diagnosis was confirmed by transjugular liver biopsy. In 11 patients the procedure served to clarify clinical uncertainty, whereas in 9 of 54 (16.7%) the diagnosis was altered after transjugular liver biopsy. The percentage of necrosis was the only histological parameter that appeared to have significant discriminatory prognostic value, with only 2 of 19 survivors having greater than 70% necrosis. Twenty-one of these biopsy specimens were reviewed by two pathologists, and their degree of correlation for the various features was assessed. Almost perfect concordance was found between the two pathologists on the percentage of hepatocellular necrosis. The King’s College criteria correctly identified outcome in 100% of patients with acetaminophen-induced fulminant liver failure and in 91% of nonsurvivors and 82% of survivors with nonacetaminophen-induced fulminant liver failure. In six of eight nonsurvivors and two survivors with nonacetaminophen-induced fulminant liver failure, in whom the King’s College criteria were inconclusive, the percentage of necrosis correctly predicted the outcome. These results indicate that transjugular liver biopsy is both safe and effective as an adjuvant to the King’s College criteria in the diagnosis and prognosis of patients with nonacetaminophen-induced fulminant liver failure. (HEPATOLOGY 1993;18:1370-1374.)
Lipoylated and unlipoylated domains of human PDC-E2 as autoantigens in primary biliary cirrhosis: Significance of lipoate attachment
Authors: Quinn Janet , Diamond Austin G. , Palmer Jeremy M. , Bassendine Margaret F. , James Oliver F. W. , Yeaman Stephen J.
Published: March 2007

Approximately 95% of patients with primary biliary cirrhosis have antimitochondrial antibodies against the E2 component of the pyruvate dehydrogenase complex (E2p). Immunodominant sites on E2p have been localized to the inner lipoyl domain, which serves as a covalent attachment site for the essential cofactor, lipoic acid. However, it is not clear whether the presence of lipoic acid is necessary for autoimmune recognition of human E2p. To facilitate further studies on the inner lipoyl domain and to assess the importance of lipoic acid in antibody binding, we used the previously cloned human E2p cDNA in the construction and high-level expression in Escherichia coli of a subgene encoding the domain. Purification and analysis of the gene product revealed that both lipoylated and unlipoylated forms of the intact domain are generated. Immunoblotting, enzyme-linked immunosorbent assay inhibition experiments and antibody affinity measurements using isolated lipoylated and unlipoylated domains demonstrated that the presence of the lipoyl residue is crucial for effective recognition by primary biliary cirrhosis patients’ autoantibodies, which have a higher relative affinity for the lipoylated form. Contrary to some previous suggestions, these results indicate that antibodies in primary biliary cirrhosis patients’ sera bind most effectively to a unique peptide-cofactor conformation in the lipoyl domain of the human E2p polypeptide. Moreover, the availability of large amounts of human lipoyl domain will permit further studies into the role of the antigen (if any) in disease pathogenesis. (HEPATOLOGY 1993;18:1384-1391.)
A prospective study of biliary cytology in 100 patients with bile duct strictures
Authors: Kurzawinski Tomasz R. , Deery Alastair , Dooley James S. , Dick Robert , Hobbs Kenneth E. F. , Davidson Brian R.
Published: March 2007

In patients with obstructive jaundice due to biliary tract stricture a tissue diagnosis is essential because of the varied treatment options available. Radiological imaging of a biliary stricture may suggest that it is malignant, but only a tissue diagnosis can be conclusive. The difficulty of obtaining biopsy tissue has encouraged the use of cytology in this field. This study prospectively analyzed the diagnostic value of exfoliative bile and brush cytology methods. One hundred consecutive patients with biliary strictures diagnosed at endoscopic retrograde cholangiopancreatography or percutaneous transhepatic cholangiography (60 men and 40 women; median age = 71 yr, range = 31 to 91 yr) underwent biliary cytology and were divided into two groups. Group 1 comprised the first 47 patients, who were studied by means of bile cytology alone; and group 2 comprised the subsequent 46 patients, who were studied by means of bile and brush cytology techniques. Seven patients were excluded from analysis because of inadequate follow-up information. A single experienced cytologist examined all samples to determine whether they were neoplastic. Eighty-one patients had malignant strictures and 12 had benign strictures. Combined bile and brush cytology (group 2) was more sensitive than bile cytology alone (group 1) (69% [27 of 39] vs. 33% [16 of 42], p < 0.01). In the patients studied by means of bile and brush cytology methods (group 2), cytologic study of brushings was more sensitive (69% vs. 26%, p < 0.01). No false-positive results were reported in either group (specificity = 100%). No procedure-related complications occurred. Sampling time averaged less than 5 min. Biliary cytology is an effective way of obtaining a tissue diagnosis, with brush methods more sensitive than bile cytology. Cell sampling is rapid and safe to perform and should be done routinely in cases of biliary stricture. (HEPATOLOGY 1993;18:1399-1403.)
Evidence for neurological dysfunction in end-stage protoporphyric liver disease
Authors: Rank Jeffrey M. , Carithers Robert , Bloomer Joseph
Published: March 2007

Protoporphyria is a genetic disorder characterized by a defect in the enzyme ferrochelatase, which catalyzes the chelation of iron to protoporphyrin. This causes excessive accumulation and excretion of protoporphyrin. The predominant clinical feature is photosensitivity. Progressive and fatal liver disease occurs in a small percentage of cases. We report our experience with eight patients with end-stage protoporphyric liver disease in whom a syndrome developed before transplantation that resembled the neurological crises of the acute porphyrias. This syndrome was characterized by abdominal pain, hypertension, tachycardia, extremity pain and weakness, constipation and nausea and vomiting. Erythrocyte and serum protoporphyrin levels were markedly increased in all patients. In one patient, profound hemolysis developed during the anhepatic phase of transplantation and continued over a period of 72 hr, causing an extreme increase in the serum protoporphyrin level. Progressive weakness deteriorated to paralysis in this patient. This phenomenon suggests that protoporphyrin may gain access to neural tissue when serum levels are markedly increased, causing neurotoxicity. (HEPATOLOGY 1993;18:1404-1409.)
Differential control by arterial and portal noradrenaline of hepatic carbohydrate metabolism: Evidence for an indirect hemodynamic mechanism
Authors: Miura Hisayuki , Jungermann Kurt , Gardemann Andreas
Published: March 2007

In an earlier study it was found (a) that arterial noradrenaline caused increases in glucose and lactate output slower in onset, smaller in peak height and clearly longer in duration than those caused by portal noradrenaline and (b) that arterial noradrenaline was extracted to a much greater extent than portal noradrenaline. It is possible that the differences in the actions of arterial and portal noradrenaline were due to the different hemodynamic changes; arterial noradrenaline reduced hepatic flow more strongly and with different kinetics than did portal noradrenaline. Therefore the effects of arterial and portal noradrenaline were investigated in isolated rat liver, singlepass perfused through both the hepatic artery (100 cm H2O, 30% flow) and the portal vein (15 cm H2O, 70% flow), after inhibition of the hemodynamic alterations by the Ca2+ antagonist nifedipine. We found (a) that nifedipine inhibited the hemodynamic changes by arterial noradrenaline strongly and those by portal noradrenaline slightly, (b) that the remaining hemodynamic alterations in the presence of high concentrations of the Ca2+ antagonist (100 μmol/L)-slight decrease in portal flow with unaffected arterial flow- were essentially identical after arterial and portal application of noradrenaline, (c) that the pronounced kinetic differences in the alterations by arterial and portal noradrenaline of glucose and lactate balance were diminished by 50 μmol/L nifedipine and abolished by 100 μmol/L of the Ca2+ antagonist and (d) that the different hepatic extractions of arterial and portal noradrenaline were greatly reduced and almost equalized by nifedipine. These observations allow the conclusion that the differences in the metabolic changes by arterial and portal noradrenaline were caused indirectly by the pronounced differences in the hemodynamic altercations after arterial and portal application of this catecholamine. They confirm earlier morphological and biochemical observations that, in principle, arterial and portal blood reach similar areas of liver parenchyma. (HEPATOLOGY 1993;18:1410-1415.)
Effects of nitric oxide and cyclooxygenase inhibition on splanchnic hemodynamics in portal hypertension
Authors: Wu Yuping , Burns Cartland R. , Sitzmann James V.
Published: March 2007

Portal hypertension is associated with splanchnic hyperemia and increased plasma levels of prostacyclin. Recently, nitric oxide was proposed as a mediator of this arterial vasodilatation. We hypothesized that portal hypertension alters the relative contribution of prostacyclin and nitric oxide to splanchnic vasomotor control. We studied the relationship of nitric oxide and prostaglandins in normal and portal-hypertensive (3 wk after partial portal vein ligation) male rabbits at baseline and following increasing doses of indomethacin, LG-nitro-L-arginine methylester or both. L-arginine was used as the control. Aortic, central and portal venous pressures were measured directly. Blood flow in the superior mesenteric artery was measured by means of an ultrasonic flow probe, and resistance was calculated. LG-nitro-L-arginine methylester produced vasoconstriction (increased resistance and decreased blood flow in the superior mesenteric artery) in normal and portal-hypertensive rabbits, although in portal hypertensive animals resistance and superior mesenteric artery blood flow remained significantly different than that in normal rabbits because of preexisting hyperemia. L-arginine reversed the effect of LG-nitro-L-arginine methylester. Cyclooxygenase blockade induced dose-dependent vasoconstriction in normal and portal-hypertensive animals. Indomethacin induced further vasoconstriction after LG-nitro-L-arginine methylester and reduced portal venous pressure in portal-hypertensive animals. We conclude that this indicates an amplified role for some prostaglandin, probably prostacyclin, in portal hypertension hemodynamics. It also implies that the two vasodilators act by way of independent mechanisms. (HEPATOLOGY 1993;18:1416-1421.)
Handling of epidermal growth factor and number of epidermal growth factor receptors are changed in aged male rats
Authors: Marti Ulrich
Published: March 2007

In the aged liver, cell proliferation and induction of DNA synthesis by epidermal growth factor is impaired. Changes in the hepatic handling of epidermal growth factor may be important for these effects. I compared epidermal growth factor handling in the livers of young and old rats. Epidermal growth factor binding capacity of plasma membranes was reduced from 1.30 ± 0.15 to 0.51 ± 0.19 pmol/mg in young and old animals, respectively. Intracellular handling of epidermal growth factor was assessed by means of portal injection of 125I-labeled epidermal growth factor and collection of bile samples. The extraction of epidermal growth factor showed no significant difference. After 60 min the remaining radioactivity in the aged liver was half that in young liver. The total radioactivity secreted into bile was reduced from 16.5% ± 5.7% to 10.0% ± 2.3% of the injected dose in young and old animals, respectively. Per gram of liver and per 106 cpm injected, the old animals secreted only 30.9% of the amount secreted by young animals. The secretion of immunologically intact epidermal growth factor into bile was reduced from 1.6% ± 0.8% to 0.78% ± 0.2% of the injected dose in the young and old animals, respectively. Perfusion experiments showed that in aged liver the amount of total radioactivity secreted into the perfusate was increased to 133.6% that of the young liver. Per gram of liver and per 106 cpm injected, however, we found a reduction to 80.7%. Exocytosis at the canalicular and basolateral membrane appeared to be differently affected by aging. (HEPATOLOGY 1993;18:1432-1436.)
Regulation of tissue inhibitor of metalloproteinases-1 gene expression by cytokines and dexamethasone in rat hepatocyte primary cultures
Authors: Roeb Elke , Graeve Lutz , Hoffmann Rolf , Decker Karl , Edwards Dylan R. , Heinrich Peter C.
Published: March 2007

The steady-state levels of extracellular matrix proteins are regulated by the rates of their synthesis and degradation. Metalloproteinases and their specific inhibitors, tissue inhibitor of metalloproteinases-1 and -2 are believed to play a crucial role in extracellular matrix protein degradation. Here we show that the tissue inhibitor of metalloproteinases-1 is expressed in rat hepatocytes in primary culture and regulated by inflammatory cytokines. Rat hepatocytes constitutively express mRNA of tissue inhibitors of metalloproteinases-1 at a low level. Incubation with conditioned medium from lipopolysaccharide-stimulated human monocytes led to a dramatic induction of mRNA of tissue inhibitors of metalloproteinases-1. The inflammatory cytokines interleukin-1β, interleukin-6, interleukin-11, leukemia inhibitory factor and ciliary neurotrophic factor were also capable of stimulating expression of mRNA of tissue inhibitors of metalloproteinases-1. Among these cytokines interleukin-6 was the most potent stimulator. The combination of interleukin-1β, interleukin-6 and interleukin-11 synergistically up-regulated mRNA of tissue inhibitors of metalloproteinases-1. The synthetic glucocorticoid dexamethasone dose dependently inhibited constitutive and interleukin-6-induced expression of tissue inhibitors of metalloproteinases-1. A possible involvement of tissue inhibitor of metalloproteinases-1 in the pathogenesis of liver fibrosis and cirrhosis is discussed. (HEPATOLOGY 1993;18:1437-1442.)
Stimulation of liver growth by exogenous human hepatocyte growth factor in normal and partially hepatectomized rats
Authors: Fjuiwara Kenji , Nagoshi Sumiko , Ohno Akihiko , Hirata Keiichi , Ohta Yasuhiko , Mochida Satoshi , Tomiya Tomoaki , Higashio Kanji , Kurokawa Kiyoshi
Published: March 2007

Human hepatocyte growth factor stimulates DNA synthesis by cultured rat hepatocytes. When human hepatocyte growth factor prepared from the culture medium of human embryonic lung fibroblasts was intravenously injected into normal rats and rats after 70% hepatectomy, it was detected in hepatocytes but not in nonparenchymal cells isolated 30 min after injection. Similar injections of human hepatocyte growth factor at 2-hr intervals for 10 hr significantly increased hepatic DNA content in normal rats at 48 hr, with increased hepatic content of putrescine, the essential polyamine for hepatic DNA synthesis after 70% hepatectomy, and activities of catalytic enzymes of putrescine synthesis at 6 hr almost to the levels in rats after 70% hepatectomy. Those levels in rats after 70% hepatectomy were further enhanced by similar injections of human hepatocyte growth factor starting immediately after surgery. Increased hepatic DNA content in normal rats and rats after 70% hepatectomy was also seen with recombinant human hepatocyte growth factor to a greater extent compared with that seen with human hepatocyte growth factor. In normal rats given recombinant human hepatocyte growth factor, 5-bromo-2′-deoxyuridine-labeled and mitotic hepatocytes were significantly increased in number at 26 hr but not at 48 hr. We conclude that exogenous human hepatocyte growth factor acts as a trigger and a promoter of liver growth to increase hepatic putrescine production in rats. Recombinant human hepatocyte growth factor is more potent than human hepatocyte growth factor in this action. (HEPATOLOGY 1993;18:1443-1449.)
Capillarization and venularization of hepatic sinusoids in porcine serum-induced rat liver fibrosis: A mechanism to maintain liver blood flow
Authors: Bhunchet Ekapot , Fujieda Kaori
Published: March 2007

The processes of capillarization and venularization of sinusoids after porcine serum-induced rat liver fibrosis were studied by light and electron microscopy. Accompanying the development of fibrosis in the walls of central veins, most of the sinusoidal outlets collapsed, resulting in the formation of hepatic limiting plates around central veins. A few remaining sinusoids underwent capillarization (the development of a basal lamina and the defenestration of the sinusoidal endothelial cell), followed by venularization (the transformation into venules of sinusoids, characterized by the enlargement of the diameters with the lumina being lined with several endothelial cells, which lose fenestrae and develop a basal lamina). These newly formed venules served to maintain blood flow from sinusoids into central veins and thus have been designated the “outlet venules.” Diameters of these venules could reach about 25 μm. They were classified into two types: (a) the septal outlet venules, which developed inside the septa; and (b) the angular outlet venules, which drained blood directly from the parenchyma into the fibrotic central veins at the angles between two septa. Associated with venularization, perisinusoidal stellate cells (fat-storing cells or Ito cells) differentiated to myofibroblasts. (HEPATOLOGY 1993;18:1450-1458.)
Increased benzodiazepine-like activity is neither necessary nor sufficient to explain acute hepatic encephalopathy in the thioacetamide-treated rat
Authors: Widler Peter , Fisch Hans U. , Schoch Peter , Zimmermann Arthur , Schläpfer Thomas E. , Reichen Jürg
Published: March 2007

Increased levels of natural benzodiazepine receptor agonists, produced in the body (endogenous) or ingested with food (exogenous) have been proposed as one of the factors causing hepatic encephalopathy in both experimental animals and human subjects. However, the divergent response of hepatic encephalopathy to benzodiazepine antagonists sheds doubt on this attractive hypothesis. Acute liver failure was induced in male Sprague-Dawley rats (n = 17) with intraperitoneal thioacetamide (600 mg/kg/day for 3 days) while 14 control rats received vehicle only. Acute liver failure developed in all treated rats (AST: 1,898 ± 1,359 IU/L vs. controls, 45 ± 5 IU/L, p < 0.005; bilirubin: 36 ± 27 μmol/L vs. controls, 1.5 ± 0.5 μmol/L, p < 0.005; centrizonal necrosis) and grade 3 or 4 hepatic encephalopathy (neurologic assessment and activity monitoring). However, benzodiazepine receptor ligand activity, measured in the supernatant of whole-brain homogenates with a [3H]fiumazenil binding competition assay, was clearly increased in only 1 of 17 rats with acute liver failure compared with controls (52.7 ± 34.1 vs. 44.3 ± 18.9 ng diazepam equivalents/gm; NS). To evaluate whether the reported increase in benzodiazepine receptor ligand activity could be due to prolonged residence of exogenous benzodiazepine-like substances, additional rats with acute liver failure and controls were treated with diazepam (five doses of 0.5 mg/kg at 12-hr intervals by gavage). Benzodiazepine receptor ligand activity was greater in animals with acute liver failure than in controls (223 ± 65 vs. 103 ± 23 ng diazepam equivalents/gm; p < 0.002) 1 to 3 hr after the last diazepam dose. Increased tissue levels of benzodiazepine receptor ligand activity are therefore neither necessary nor sufficient to explain the pathogenesis of hepatic encephalopathy in acute liver failure. We conclude that increased tissue levels of benzodiazepine receptor agonists in hepatic encephalopathy could be due to prolonged residence of exogenous benzodiazepine-like compounds of pharmaceutical or natural origin. (HEPATOLOGY 1993;18:1459-1464.)
Degradation and intracellular accumulation of a residualizing hyaluronan derivative by liver endothelial cells
Authors: McGary Carl T. , Yannariello-Brown Judith , Kim Dennis W. , Stinson Tami C. , Weige Paul H.
Published: March 2007

The release and intracellular accumulation of 125I-hyaluronan degradation products was studied in cultured liver endothelial cells with hyaluronan oligosaccharides (relative molecular mass = approximately 44,000) uniquely modified and radiolabeled at the terminal reducing sugar. Two methods were combined to measure 125I-hyaluronan degradation by liver endothelial cells. (a) Cetylpyridinium chloride precipitation of hyaluronan oligosaccharides was used as a rapid, convenient assay to monitor the appearance of hyaluronan degradation products. Hyaluronan oligosaccharides less than 54 to 60 monosaccharides in length were not precipitated with cetylpyridinium chloride and thus were assessed as degraded. (b) Gel filtration chromatography was used to estimate the size range of oligosaccharides produced by liver endothelial cells. After internalization of 125I-hyaluronan, liver endothelial cells released radioactive degradation products into the culture media after a lag period of 2.5 to 3.0 hr. The intracellular accumulation of degraded 125I-hyaluronan was linear for at least 2 hr even though no degradation products were released. The long lag before release of degraded 125I-hyaluronan is likely caused by the modified chemical structure at the reducing end of the hyaluronan derivative; the derivative acts like a residualizing label. After this lag the release of degraded 125I-hyaluronan proceeded linearly for up to 12 hr. The extracellular 125I-hyaluronan degradation products eluted with a distribution coefficient of 1.3 on a gel filtration column. The major intracellular 125I-labeled degradation product showed the same retardation (distribution coefficient = 1.3). This retention may be caused by the hydrophobic aromatic and alkyl modifications to the former reducing sugar, also characteristics of a residualizing label. In addition, at least two larger minor intermediates were observed intracellularly. The rate of intracellular 125I-hyaluronan degradation was dependent on hyaluronan concentration and reached a maximal rate (159 molecules/cell/sec) at 2 × 10−7 mol/L. This was about half the maximal rate of endocytosis (285 molecules/cell/sec) at a hyaluronan concentration of 1.3 × 10−7 mol/L. The apparent ligand concentration that gives half-maximal responses for endocytosis and intracellular degradation was 0.6 × 10−7 and 1.0 × 10−7 mol/L, respectively. (HEPATOLOGY 1993;18:1465-1476.)
Production of chemotactic factor, interleukin-8, from hepatocytes exposed to ethanol
Authors: Shiratori Yasushi , Takada Hiroshi , Hikiba Yohko , Nakata Ryo , Okano Ken’Ichi , Komatsu Yutaka , Niwa Yasuro , Matsumura Masayuki , Shiina Shuichiro , Omata Masao , Kamii Kazuo
Published: March 2007

In a previous paper, we demonstrated proteinous chemotactic factors released from hepatocytes exposed to ethanol. In this study, we further characterized the chemotactic factors released from ethanoltreated hepatocytes. After fractionating the conditioned medium with gel chromatography, we demonstrated chemotactic activity at molecular weights of around 20 and 40 kD. When the conditioned medium was mixed with antiserum against interleukin-8, chemotactic activity was almost completely abolished. In addition, antiserum against interleukin-8 completely reduced chemotactic activity of the 20-kD chemotactic factor but did not influence the chemotactic activity of the 40-kD chemotactic factor. After gel electrophoresis of the conditioned medium, the protein reacted with antibody against interleukin-8 was demonstrated at a molecular weight of 20 kD but was not found at a molecular weight of 40 kD. These results suggest that a major part of the proteinous chemotactic factors released from hepatocytes exposed to ethanol could be a dimer form of interleukin-8, one of the proinflammatory cytokines, possibly contributing to the pathogenesis of alcoholic hepatitis. (HEPATOLOGY 1993;18:1477-1482.)
Differential impact of carolina rinse and university of wisconsin solutions on microcirculation, leukocyte adhesion, kupffer cell activity and biliary excretion after liver transplantation
Authors: Post Stefan , Palma Pablo , Rentsch Markus , Gonzalez Alberto P. , Menger Michael D.
Published: March 2007

This quantitative in vivo fluorescence microscopy study investigated the relative impact of an optimized rinse solution (warm Carolina rinse) and that of an established storage solution (University of Wisconsin solution) on various pathomechanisms of hepatic reperfusion injury after cold storage. Syngeneic orthotopic, arterialized liver transplantation was performed in male Lewis rats after 24 hr of cold ischemia (n = 24). The four experimental groups differed according to the type of preservation/rinse solution used: University of Wisconsin solution/albumin rinse (group 1), autologous blood (just external cooling)/albumin rinse (group 2), blood/Carolina rinse (group 3) and University of Wisconsin solution/Carolina rinse (group 4). Hepatic microvascular perfusion, leukocyte accumulation and phagocytic activity of Kupffer cells were assessed by means of intravital fluorescence microscopy 30 to 90 min after reperfusion. Disturbances of microvascular perfusion were most pronounced in group 2, markedly reduced by University of Wisconsin solution (group 1) and Carolina rinse (group 3) and minimized by combined use of University of Wisconsin solution and Carolina rinse in group 4. Intrahepatic leukocyteendothelium interaction in sinusoids and postsinusoidal venules was found to depend on the application of Carolina rinse before reperfusion rather than the use of University of Wisconsin solution during cold storage. Activation of phagocytosis by Kupffer cells was most pronounced in group 1, intermediate in groups 2 and 3 and not noticeable in group 4. Hepatocellular excretory function as assessed on the basis of total bile flow and excretion of bile acids during the first 90 min after reperfusion was found to be improved by application of Carolina rinse, both after storage in blood or in University of Wisconsin solution. We conclude that, in this model, flushing the graft with Carolina rinse before reperfusion may attenuate various manifestations of reperfusion injury, irrespective of the type of preservation solution used. However, because of apparently synergistic actions minimal injury is observed when preservation in University of Wisconsin solution and rinse with Carolina rinse are combined. (HEPATOLOGY 1993;18:1490-1497.)
Increased dietary fat content accelerates cholesterol gallstone formation in the cholesterol-fed prairie dog
Authors: Lamorte Wayne W. , O’Leary Daniel P. , Booker Michael L. , Scott Thayer E.
Published: March 2007

Epidemiological studies have provided conflicting information about the relationship between fat consumption and gallstone formation. We studied cholesterol gallstone formation in prairie dogs after 1 wk of the following diets: (group A) a control diet with no added cholesterol and 5% of calories from corn oil, (group B) 1.2% cholesterol with 5% of calories from corn oil or (group C) 1.2% cholesterol with 40% of calories from corn oil. In controls serum cholesterol was 58.9 ± 4.5 mg/dl, gallbladder bile was unsaturated with cholesterol (cholesterol saturation index = 0.7 ± 0.1; cholesterol = 3.8 mmol/L) and none of 12 animals formed cholesterol crystals or stones. The low-fat diet supplemented with cholesterol (group B) increased serum and biliary cholesterol concentrations to 292 ± 76 mg/dl and 7.5 ± 1.1 mmol/L, respectively (p < 0.05), but cholesterol saturation index was only modestly increased (1.1 ± 0.1) and in only one of eight animals did cholesterol monohydrate crystals develop. Group C, animals, which recceived cholesterol plus high levels of corn oil, had higher serum cholesterol levels (457 ± 66 mg/dl), higher biliary cholesterol concentrations (16.6 ± 1.3 mmol/L), higher cholesterol saturation indexes (1.7 ± 0.1) and increased incidence of cholesterol gallstones (5 of 11). The two cholesterolsupplemented diets increased biliary phospholipid concentrations, decreased the ratio of cholic/chenodeoxycholic acid and increased the proportion of biliary lecithins containing linoleic acid, but these abnormalities were greatest in group C, which was given large amounts of corn oil. These findings suggest that cholesterol gallstone formation in the prairie dog is accelerated by increased dietary omega-6 polyunsaturated triglycerides. (HEPATOLOGY 1993;18:1498-1503.)
Increase in prostanoid formation in rat liver macrophages (Kupffer cells) by human anaphylatoxin C3a
Authors: Püschel Gerhard P. , Hespeling Ursula , Oppermann Martin , Dieter Peter
Published: March 2007

Human anaphylatoxin C3a increases glycogenolysis in perfused rat liver. This action is inhibited by prostanoid synthesis inhibitors and prostanoid antagonists. Because prostanoids but not anaphylatoxin C3a can increase glycogenolysis in hepatocytes, it has been proposed that prostanoid formation in nonparenchymal cells represents an important step in the C3a-dependent increase in hepatic glycogenolysis. This study shows that (a) human anaphylatoxin C3a (0.1 to 10 μg/ml) dose-dependently increased prostaglandin D2, thromboxane B2 and prostaglandin F2α formation in rat liver macrophages (Kupffer cells); (b) the C3amediated increase in prostanoid formation was maximal after 2 min and showed tachyphylaxis; and (c) the C3a-elicited prostanoid formation could be inhibited specifically by preincubation of C3a with carboxypeptidase B to remove the essential C-terminal arginine or by preincubation of C3a with Fab fragments of a neutralizing monoclonal antibody. These data support the hypothesis that the C3a-dependent activation of hepatic glycogenolysis is mediated by way of a C3a-induced prostanoid production in Kupffer cells. (HEPATOLOGY 1993;18:1516-1521.)
DNA/protein complexes delivered in conjunction with adenovirus generate high-efficiency in vitro transfection: A powerful transfection reagent with potential broad applications
Authors: Askari Fred
Published: March 2007

We have combined a receptor-mediated DNA delivery system with the endosomal lysis ability of adenovirus and shown that DNA can be delivered into primary hepatocytes, resulting in a high level of gene expression. When asialoorosomucoid conjugated with poly(L-lysine) was used to deliver the Escherichia coli β-galactosidase gene into primary hepatocytes through binding with the hepatic asialoglycoprotein receptor, only a low level of β-galactosidase was detectable, with less than 0.1% of the hepatocytes being transfected. This level of activity can be greatly enhanced by the cointernalization of the DNA protein complex with a replication-defective adenovirus, resulting in 100% of the hepatocytes staining blue with 5-bromo-4-chloro-3-indolyI β-D-galactoside. Quantitative analysis of β-galactosdase expression also showed a 1000-fold enhancement of activity. To test the applicability of this DNA delivery system for the correction of phenylketonuria, a metabolic disorder that causes severe mental retardation in children, we have delivered the human phenylalanine hydroxylase (PAH) gene to hepatocytes derived from a PAH-deficient mouse strain and dem-onstrated complete reconstitution of enzymatic activity. This method shows great promise for efficient gene delivery to the liver for correction of hepatic disorders.
Treatment of chronic hepatitis C with recombinant human interferon-α2a: Results of a randomized controlled clinical trial
Authors: Diodati Giulio , Bonetti Paola , Noventa Franco , Casarin Carla , Rugge Massimo , Scaccabarozzi Sergio , Tagger Alessandro , Pollice Lucio , Tremolada Federico , Davite Cristina , Realdi Giuseppe , Ruol Arturo
Published: March 2007

Sixty consecutive patients with chronic hepatitis C were included in a randomized controlled trial of recombinant human interferon-α2a vs. no treatment. Treated patients received tapering doses of interferon thrice weekly for 1 yr. Twenty treated cases (66.7) normalized serum aminotransferase levels within the first 4 mo of treatment, but reactivation or breakthrough frequently occurred afterward (20 in both cases). Only one of the untreated patients showed spontaneous normalization of serum aminotransferase levels. Liver histology did not improve in patients without a biochemical response or with breakthrough during therapy, whereas it did not worsen in long-term responders and reactivating patients. Lack of response does not appear to be related to serum interferon antibodies, although their early appearance is more frequent in patients who showed reactivation later on. No biochemical parameter was found to be predictive for positive response to treatment. Antibody to c100 became negative in 62.5 of long-term responders, whereas no change was recorded in other treated patients or controls. Reactivation and breakthrough often occur during treatment, and further studies are needed to determine the most effective schedule (dose and time) of interferon treatment. Loss of c100 antibody during therapy may be a marker of long-term maintenance of response to interferon therapy. (Hepatology 1994;19:1-5).
Hepatitis C virus genotypes: An investigation of type-specific differences in geographic origin and disease
Authors: Dusheiko Geoffrey , Schmilovitz-Weiss Hemda , Brown David , McOmish Fiona , Yap Pong-Lee , Sherlock Sheila , McIntyre Neil , Simmonds Peter
Published: March 2007

Because of the nucleotide sequence diversity of different isolates of hepatitis C virus, it has become important to clarify whether distinct genotypes of hepatitis C virus vary with respect to pathogenicity, infectivity, response to antiviral therapy and geographic clustering. We assessed nucleotide sequence variability in the 5′ noncoding region of hepatitis C virus, using restriction enzymes to analyze the distribution of hepatitis C virus genotypes, in 80 patients with chronic hepatitis C virus infection. Genotypes were correlated with demographic, clinical and histological features. Thirty-seven patients were infected with type 1, 10 had type 2 and 8 had type 3, and another 23 were infected with a new distinct hepatitis C virus type now classified as type 4. Two were infected with variants whose classification are uncertain. Types 1, 2 and 3 were found in patients from the United Kingdom, southern Europe, Asia, Africa and South America. Nineteen of 23 type 4 genotype isolates were from Middle Eastern patients, compared with 0 of 37 type 1 isolates (p < 0.001). Of 21 Middle Eastern patients, 19 (90.4) had type 4 hepatitis C virus (p = 0.001, odds ratio = 9). We found no significant difference between the mean ages or mean serum aminotransferase concentrations between the various types. Types 1,2,3 and 4 were found in patients with mild-to-moderate disease or severe disease. However, 21 of 29 (72.4) patients with type 1 who underwent liver biopsy had severe chronic hepatitis, cirrhosis or hepatocellular carcinoma histologically; 8 had mild or moderate chronic hepatitis without cirrhosis (p = 0.03, odds ratio = 2.6). Poor response to interferon-α was noted in patients with type 1 disease. Our data suggest significant geographic clustering of type 4 disease in the Middle East area. Although different hepatitis C virus genotypes can be encountered in both mild and severe disease, type 1 hepatitis C virus may have important clinical implications. The prognostic importance of these genotypes will require prolonged follow-up studies. (Hepatology 1994;19:13-18).
The hepatitis B virus PreS2/St transactivator utilizes AP-1 and other transcription factors for transactivation
Authors: Lauer Ulrich , Weiβ Ludwig , Lipp Martin , Hofschneider Peter Hans , Kekulé Alexander S.
Published: March 2007

Integrated hepatitis B virus DNA cloned from hepatitis B virus-associated hepatocellular carcinoma frequently contains 3′-truncated middle surface genes (preS2/St), which were recently found to have a transcriptional transactivator function. Because preS2/St, among others, is able to transactivate the promoters of the cellular oncogenes c-myc and c-fos, it has been speculated that integrated preS2/St genes might contribute to hepatitis B virus-associated liver carcinogenesis. In this study, we investigated the mechanism of target gene stimulation by preS2/St. It was found that deletion of a fragment containing the binding site for transcription factor AP-1 (Jun-Fos) substantially decreases inducibility of the human c-myc promoter by preS2/St. A subsequent investigation of AP-1 activation by preS2/St revealed the following: (a) insertion of multimeric AP-1 binding sites confers inducibility to an otherwise unstimulatable test promoter; (b) transactivation of AP-1 sites is dramatically increased when Jun and Fos are overexpressed by cotransfected expression plasmids; and (c) inhibitors of AP-1 activation also impair transactivation by preS2/St. Besides AP-1, preS2/St was also able to utilize the unrelated transcription factors NF-kB and AP-2 for transactivation, suggesting that the gene product of preS2/St acts indirectly through one or several general cellular pathways rather than as a bona fide transcription factor. Because AP-1 conveys induction of a large panel of tumor-relevant genes, its preS2/St-dependent activation implies a possible causative role in hepatitis B virus-associated hepatocarcinogenesis. (Hepatology 1994;19:23-31).
Flumazenil in cirrhotic patients in hepatic coma: A randomized double-blind placebo-controlled crossover trial†
Authors: Pomier-Layrargues Gilles , Giguère J. F. , Lavoie J. , Perney P. , Gagnon S. , D’Amour M. , Wells J. , Butterworth Roger F.
Published: March 2007

Previous reports have suggested that “endogenous” benzodiazepines could contribute to neural inhibition in hepatic encephalopathy. RO 15-1788 (flumazenil), a specific antagonist of brain benzodiazepine receptors, could thus reverse the neurological symptoms of hepatic encephalopathy. To test this possibility, we conducted a double-blind, placebo-controlled crossover trial of the efficacy of flumazenil in cirrhotic patients in hepatic coma. Seventy-seven cirrhotic patients in hepatic coma were evaluated. Fifty-six were excluded from the trial because of multiorgan failure or because coma was precipitated by prior use of benzodiazepines, and 21 patients were randomly assigned to the flumazenil group (11 patients) or the placebo group (10 patients). Treatment was administered intravenously as a 20-ml solution (placebo or 2 mg flumazenil); seven patients were crossed over. Clinical status was assessed blindly by two observers, using a modified Glasgow scale, every 15 min for 6 hr. Electroencephalogram tracings obtained before and after drug administration were evaluated blindly by two independent observers. Serum concentrations of benzodiazepines before treatment were measured by means of a fluorescence polarization immunoassay. Improvement in neurological symptoms was observed in six patients treated with flumazenil, whereas none in the placebo group showed improvement (p < 0.05; Fisher’s exact test). Improvements in electroencephalogram tracings were demonstrated in four patients treated with flumazenil, compared with two patients in the placebo group (p = NS). Benzodiazepines were found in the serum of four patients treated with flumazenil (two responders and two nonresponders); all of these patients had received pharmaceutical benzodiazepines 4 to 6 days before the trial. We conclude that flumazenil is effective in a subset of highly selected cirrhotic patients with severe hepatic encephalopathy and that this beneficial effect is not related to the presence of benzodiazepines in the blood. (Hepatology 1994;19:32-37).