bluuebunny/crossref_metadata_2025 huggingface dataset:
Nuclear scaffold-associated protease: In situ nuclear localization and effects of a protease inhibitor on growth and morphology of a ras -transformed hepatocyte cell line
Authors: Clawson Gary A. , Ren Ling , Isom Harriet C.
Published: March 2007

We have previously identified a multicatalytic protease (MCP) activity associated with the nuclear scaffold (NS) in hepatocytes and fibroblasts. When we used the chloromethylketone protease inhibitor AAPFcmk, which is targeted to chymotrypsinlike protease activity, we observed a dramatic inhibition of transformation of fibroblasts, with effects that were relatively selective for the NS fraction. Here, we undertook experiments to determine the effects of AAPFcmk on Simian Virus 40-immortalized CWSV1 cells compared with a ros-transformed hepatocyte cell line (NR4) derived from CWSV1. We used biotinAAPFcmk and fluorescent reagents to demonstrate a nuclear chymotrypsinlike protease activity, which is most prominent at the nuclear envelope. The ras-transformed NR4 cells were highly susceptible to growth inhibition in a dose-dependent manner, showing 85% growth inhibition at 50 μmol/L AAPFcmk. In contrast, the immortalized CWSV1 cells were not sensitive at the concentrations (10 to 50 μmol/L) of AAPFcmk tested. In subcellular fractionation studies, the inhibitory effects of AAPFcmk were confined to the NS fraction. The AAPFcmk-induced growth inhibition was accompanied by marked morphological changes in ras-transformed cells, without evidence of overt toxicity. No change in DNA content was observed, but a marked increase in organization of actin cytoskeletal elements was seen. These results suggest that a protease activity associated with the nuclear scaffold has important functions in controlling cytoskeletal filament organization and cell replication. (Hepatology 1995; 22:1230-1235.).
Inactivation of kupffer cells after prolonged donor fasting improves viability of transplanted hepatic allografts
Authors: Sankary Howard N. , Chong Anita , Foster Preston , Brown Esther , Shen Jikun , Kimura Robert , Rayudu Guarimella , Williams James
Published: March 2007

Data from recent studies suggest that donor fasting imparts a beneficial effect on the viability of transplanted hepatic allografts. Because starvation may temporarily inactivate Kupffer cells, and because these cells are the likely mediators of liver injury after prolonged preservation-reperfusion, the purpose of this study is to establish a link between improved organ viability and Kupffer cell inactivation caused by donor allograft fasting. In an in vivo rat liver transplant model, 48 hours of donor fasting (1) improved allograft viability, (2) significantly decreased Kupffer cell phagocytosis, and (3) significantly decreased cytokine (tumor necrosis factor [TNF]) production postrevascularization. These data validate work from previous studies demonstrating that donor fasting improves allograft viability and furthermore support our previous research implicating activation of Kupffer cells as a causative agent of cold ischemia-preservation injury. (Hepatology 1995; 22:1236-1242.).
Oval cell differentiation into hepatocytes in the acetylaminofluorene-treated regenerating rat liver
Authors: Golding Matthew , Sarraf Catherine E. , Lalani El-Nasir , Anilkumar T. V. , Edwards Robert J. , Nagy Peter , Thorgemsson Snorri S. , Alison Malcolm R.
Published: March 2007

When hepatocyte regeneration after a two-thirds partial hepatectomy (PH) in rats is blocked by oral gavage of acetylaminofluorene, a proliferation of ductular cells ensues that results in a profusion of neoductules radiating from each portal tract. To examine the possibility that this population of newly emerging cells harbors cells capable of differentiating into hepatocytes, we have looked in these cells for expression of functional markers of hepatocyte commitment at both the RNA and protein levels. Expression of albumin and α-fetoprotein (α-FP) messenger RNA (mRNA) transcripts were sought in situ using antisense riboprobes, and the expression of a number of cytochrome P450 enzymes was examined immunohistochemically. Before any signs of differentiation the ductular cells strongly expressed cytokeratins 7, 8, 18, and 19 in the same manner as authentic bile ducts, but unlike the latter also expressed vimentin. In situ hybridization studies showed that small bile ducts close to the limiting plate, as well as the newly formed ducts, expressed albumin and α-fetoprotein messenger RNAs, and immunocytochemistry showed that the distribution of the respective proteins was similar. Beginning at 1 week after partial hepatectomy, areas of differentiation could be found in the new ducts, with cells resembling either columnar intestinal-type epithelia or hepatocytes. Intestinal-like cells expressed neither albumin, α-FP, nor cytochrome P450 enzymes, whereas ductular cells appearing like hepatocytes with the typical membranous distribution of cytokeratin 8 strongly expressed a variety of cytochrome P450 enzymes normally associated with functional hepatocytes. These observations further support the belief that reactive ductules, sprouted from small ducts, can represent an adaptive response of the liver to replenish lost hepatocytes, although some of the newborn cells appear to differentiate along intestinal lines. (Hepatology 1995; 22:1243-1253.).
Effects of liver transplantation on bile formation and biliary lipid secretion in the Sprague-Dawley rat
Authors: Chan Francis K. L. , Zhang Yikun , Sutherland Francis R. , Shaffer Eldon A.
Published: March 2007

Altered hepatic secretory function after orthotopic liver transplantation constitutes a major perioperative clinical problem. Cholestasis and cholesterol gallstone formation are among the most frequent complications reported. Such changes in the allograft secretory function can be secondary to many factors like graft injury due to preservation and marked rejection, surgical complications, immunosuppressive therapy, and sepsis. The effects of liver transplantation per se on bile formation and biliary lipid secretion are unknown. The rat model of orthotopic liver transplantation was used to characterize better the true effect of transplantation without the influence of these confounding variables. Twentyfour-hour bile collections were performed on nine transplanted versus nine liver-denervated (sham) rats 4 weeks after surgery, and nine normal Sprague-Dawley rats. The liver allografts showed mild lymphocytic infiltration in portal tracts and the serum alanine transaminase levels were not significantly elevated. Bile flow and the secretion of bile salts and bilirubin under basal conditions were unchanged. Bile salt pool size, synthesis rate, and bile acid composition did not differ among the three groups. However, cholesterol secretion was dramatically reduced (50%) in the transplanted rats and decreased 31% in the liver-denervated rats (P < .001 and .01, respectively), resulting in a more favorable cholesterol saturation index (CSI = 0.29 for transplanted and 0.32 for sham versus 0.45 for normal controls; P < .01). Thus, liver transplantation with its attendant denervation did not impair hepatic secretory function, but rather improved biliary lipid composition despite mild rejection. (Hepatology 1995; 22:1254-1258.).
Differential expression of A and B laminin chains during rat liver regeneration
Authors: Giménez América , Hostench Joaquim , Stamatoglou Stamatis C. , Enrich Carlos
Published: March 2007

We have studied the distribution and expression of laminin during rat liver regeneration by immunofluorescence and immunoblotting using affinity-purified laminin antibodies. Laminin was localized on sinusoidal surfaces in normal and regenerating hepatic parenchyma, but enhanced expression was detected during regeneration from 6 hours to 7 days after a partial hepatectomy. A and B laminin chains were specifically detected by Western blotting in highly purified plasma membrane fractions derived from the sinusoidal domain of hepatocytes. Analysis of laminin expression in whole homogenates from hepatectomized rats showed a differential expression of A and B laminin chains during regeneration: The A chain showed a progressive increase, whereas the B chain exhibited an early, prereplicative increase and then gradually declined to control levels at the end of restorative growth. The results suggest differential temporal requirements for A and B laminin chains during hepatic growth and tissue formation. (Hepatology 1995; 22:1259-1262.).
Parenchymal and nonparenchymal uptake of technetium-99m, indium-111, and iodine-125 low-density lipoprotein in the normal and estradiol-stimulated rat liver: Tracer validation for quantitative low-density lipoprotein scintigraphy
Authors: Leitha Thomas , Staudenherz Anton , Hermann Marcela , Hüttinger Manfred , Gmeiner Bernhard
Published: March 2007

This study quantifies the parenchymal and nonparen-chymal uptake of technetium-99m (99mTc)- and indium-III (111In)-low-density lipoprotein (LDL) in different states of hepatic LDL-receptor activity to validate quantitative LDL scintigraphy. Iodine-125 (125I)-LDL was used as reference tracer. Four Sprague-Dawley rats with 17-alpha-ethinyl estradiol (EE)-stimulated LDL-receptor activity and five controls received all three tracers simultaneously 90 minutes before collagenase liver perfusion and metrizamide gradient cell separation. Total liver uptake of 99mTc-, 111In-, and 125I-LDL was 1.8 ± 1.0, 1.6 ± 0.8, and 0.2 ± 0.2% injected dose/g organ weight, respectively. The contribution of nonparenchymal cells to total hepatic tracer uptake was 5.4 ± 4.7%, 11.6 ± 10.3%, and 9.6 ± 7.6% in controls. Estradiol treatment increased total liver uptake to 2.4 ± 0.5, 2.0 ± 0.2, and 0.5 ± 0.3% injected dose/g and reduced nonparenchymal cell contribution to 2.3 ± 2.6%, 4.2 ± 4.8%, and 2.6 ± 2.9%, respectively. Dual-isotope scintigraphy in EE-treated and control rats confirmed these data, with a lower total hepatic uptake of 111In-LDL in comparison with 99mTc-LDL but a comparative degree of increase by EE treatment. Both behave quantitatively comparable as residu-alizing tracers, yet 99mTc-LDL shows a higher affinity to the LDL receptor pathway of parenchymal cells. However, the nonspecific uptake of both tracers can be neglected for quantitative LDL scintigraphy, and external imaging of hepatic tracer uptake primarily reflects LDL-receptor activity of parenchymal cells. (Hepatology 1995; 22:1289-1295.).
Tyrosine kinase growth factor receptors but not seven-membrane-spanning receptors or phorbol esters activate mitogen-activated protein kinase in rat hepatocytes
Authors: Ginès Pere , Li Xiaomei , Zamarripa Jeffrey L. , Brown Susan E. S. , Wieder Eric D. , Nakamura Toshikazu , Guzelian Phillip S. , Schrier Robert W. , Heasley Lynn E. , Nemenoff Raphael A.
Published: March 2007

The response of rat hepatocytes to hormones and growth factors has been extensively studied with respect to phospholipase regulation and calcium mobilization. However, the mitogen-activated protein (MAP) kinase cascade which integrates signals from a wide variety of extracellular stimuli has not been examined in these cells. Thus, in the present study the pathways leading to activation of MAP kinase in primary cultures of adult rat hepatocytes were investigated. Growth factors acting through tyrosine kinase receptors (epidermal growth factor and hepatocyte growth factor) increased Raf and MAP kinase activity through a protein kinase C and calcium-independent pathway. Agonists acting through seven-membrane-spanning receptors (arginine vasopressin and angiotensin II) increased intracellular calcium concentration but did not stimulate Raf or MAP kinase activity. Arginine vasopressin, however, stimulated MAP kinase activity in rat 1a fibroblasts transfected with the hepatic V1a receptor and in rat aortic vascular smooth muscle cells. Phorbol 12-myristate 13-acetate (PMA) was also unable to stimulate Raf and MAP kinase in hepatocytes in spite of a marked activation of protein kinase C. We conclude that only signals arising from tyrosine kinase receptors are able to activate MAP kinase in hepatocytes. Neither agonists acting through seven-membrane-spanning receptors nor phorbol esters stimulate MAP kinase in hepatocytes. The results suggest that specific cellular components that link seven-membrane-spanning receptors with MAP kinase activation in tissues such as vascular smooth muscle are absent in rat hepatocytes. (Hepatology 1995; 22:1296-1303.).
Cytokine gene expression by Kupffer cells in experimental alcoholic liver disease
Authors: Kamimura Seiichiro , Tsukamoto Hidekazu
Published: March 2007

Kupffer cell-derived cytokines are believed to play pivotal paracrine roles in the pathogenesis of alcoholic liver disease (ALD). To evaluate this hypothesis, Kupffer cell gene expression of tumor necrosis factor-alpha (TNFα), interleukin (IL)-6, and transforming growth factor-beta 1 (TGFβ1) were directly examined in the rat model of ALD. Kupffer cells were isolated from the model after 10 and 17 weeks of intragastric ethanol infusion. These two durations resulted in focal hepatocellular injury and liver fibrogenesis, respectively. Oxidative stress as assessed by the hepatic level of thiobarbituric acid reacting substances, was evident at 10 weeks but more pronounced at 17 weeks. The steady state messenger RNA (mRNA) levels of the cytokines were examined by Northern blot analysis using RNA samples from freshly isolated Kupffer cells, and the release of the cytokines was quantitatedex vivousing a 3-day culture. The mRNA levels of TNFα and TGFβl were significantly increased by 183% and 204% at 10 weeks and 231% and 295% at 17 weeks in the ethanol-fed rats, respectively.Ex vivorelease of TNF activity by control Kupffer cells was undetectable or very low (<2U/105cells/18 hours) at both time points, but the cells from the ethanol-fed animals secreted appreciably more TNF (27.8 ± 27.6 U at 10 weeks and 40.4 ± 10.3 U at 17 weeks). The release of the latent TGFβ1 protein was also coordinately increased by 143% at 10 weeks and 238% at 17 weeks. IL-6 mRNA expression was minimal at 10 weeks, but enhanced most prominently (790%) at 17 weeks, with theex vivorelease of this cytokine increased 4-fold at the latter time point. These results show coordinate induction of TNFα, TGFβ, and IL-6 expression by Kupffer cells in progression of experimental ALD and support their paracrine roles in the ALD pathogenesis. In particular, the marked induction of Kupffer cell IL-6 gene expression at 17 Weeks suggests its possible in alcoholic liver fibrogenesis. (HEPATHOLOGY 1995;21:1304-1309.).
THE physiology of jaundice: Molecular and functional characterization of the Crigler-Najjar syndromes
Authors: Berg Carl L.
Published: March 2007

Crigler-Najjar (CN) disease is classified into two subtypes, type I and II. The molecular basis for the difference between these types is not well understood.

Several mutations in the bilirubin UDP-glucuronosyltransferase (B-UGT) gene of six CN type I and two CN type II patients were identified. Recombinant cDNAs containing these mutations were expressed in COS cells. B-UGT activity was measured using HPLC and the amount of expressed protein was quantitated using a sandwich ELISA. This enabled us to determine the specific activities of the expressed enzymes. All type I patients examined had mutations in the B-UGT1 gene that lead to completely inactive enzymes. The mutations in the B-UGT1 gene of patients with CN type II only partially inactivated the enzyme. At saturating concentrations of bilirubin (75 μM) CN type II patient A had 4.4 ± 2% residual activity and CN type II patient B had 38 ± 2% residual activity.

Kinetic constants for the glucuronidation of bilirubin were determined. The affinities for bilirubin of B-UGT1 expressed in COS cells and B-UGT from human liver microsomes were similar with K
m of 5.1 ± 0.9 μM and 7.9 ± 5.3 μM, respectively. B-UGT1 from patient B had a tenfold decreased affinity for bilirubin, K
m = 56 ± 23 μM.

At physiological concentrations of bilirubin both type II patients will have a strongly reduced conjugation capacity, whereas type I patients have no B-UGT activity. We conclude that CN type I is caused by a complete absence of functional B-UGT and that in CN type II B-UGT activity is reduced. (J. Clin. Invest. 1994. 94:2385-2391.) Key words: hereditary diseases · site directed mutagenesis · enzyme-linked immunosorbent assay · enzyme kinetics · enzyme activity. (Reproduced from The Journal of Clinical Investigation, 1994, vol. 94, pp. 2385-2391 by copyright permission of The Society for Clinical Investigation.
An outbreak of hepatitis A among south african patients with hemophilia: Evidence implicating contaminated factor VIII concentrate as the source
Authors: Kedda Mary-Anne , Kew Michael C. , Cohn Richard J. , Field Stephen P. , Schwyzer Rosemary , Song Ernest , Fernandes-Costa F.
Published: March 2007

We report an outbreak of hepatitis A in nine South African hemophiliacs treated exclusively with infusions of factor VIII concentrate. The solvent/detergent (S/D) method (which does not inactivate nonenveloped viruses) was used for virus eradication. In three of six patients studied at a molecular level hepatitis A virus (HAV) complementary DNA (cDNA) amplified from serum by reverse transcription-polymerase chain reaction (RT-PCR) was identical to HAV cDNA in 1 of 14 lots (no. 53) of factor VIII tested. The plasma for lot 53 was obtained from donors in the United States: 1 of 12 samples of this source material contained the same HAV cDNA sequences. In another two patients receiving lot 53, the degree of identity between HAV cDNA in serum and that in factor VIII was only 88% and 89%, respectively, and in the sixth patient, who did not receive lot 53, it was 90%. The degree of HAV cDNA homology among five patients in an independent point-source outbreak of hepatitis A was 100%, and that in nine patients who acquired this infection sporadically in Johannesburg, Egypt, or Russia, was 93% to 100%. Whether the three hemophiliacs with low HAV cDNA homology with lot 53 acquired the infection from other unidentified virus strains contaminating factor VIII or from extraneous sources is unknown. This study provides further evidence that factor VIII concentrate prepared by the S/D method may be contaminated by the HAV, in this instance at source, and may cause hepatitis in recipients. Proof of a cause-and-effect relationship will, however, depend on animal inoculation studies. (Hepatology 1995; 22:1363-1367).
Detection of hepatitis C virus with RNA polymerase chain reaction in fulminant hepatic failure
Authors: Villamil Federico G. , Hu Ke-Qin , Yu Chang-Hong , Lee Chao-Hung , Rojter Sergio E. , Podesta Luis G. , Makowka Leonard , Geller Stephen A. , Vierling John M.
Published: March 2007

The role of hepatitis C virus (HCV) infection in fulminant hepatic failure is controversial. The frequency of serum HCV RNA positivity in previously reported patients with fulminant hepatic failure (FHF) of indeterminate cause ranged from 0 to 12% in the United States and Europe and from 43% to 59% in Asia. We assessed serum HCV RNA using polymerase chain reaction (PCR) and oligoprimers from the 5′UTR of the HCV genome in 26 consecutive patients with FHF. Another laboratory independently performed PCR on 21 of the serum samples using different oligoprimers from the 5′UTR and NS3 region of the HCV genome. Serum HCV RNA was detected in two of seven (28%) patients with hepatitis B, 9 of 15 (60%) with an indeterminate cause, and in none with hepatitis A (n = 2) or drug-induced hepatotoxicity (n = 2). HCV RNA PCR results were concordant between both laboratories in 17 of 21 (81%) of samples. In patients with an indeterminate cause, HCV RNA positivity was significantly associated with the transmission risk factor of low socioeconomic status and Hispanic ethnicity. Eighteen patients underwent liver transplantation (LT) and 15 (83%) survived. Among patients with FHF of indeterminate cause, recurrent or acquired HCV infection after transplantation occurred in three of five (60%) and one of four (25%) patients, respectively. Three of four (75%) patients with hepatitis C virus infection post-LT also developed histologic hepatitis. HCV appears to be the causative agent of a substantial number of cases of FHF classified as indeterminate in the Los Angeles area. Differences in patient populations or risk factors may explain the discordant incidences of HCV infection in FHF observed among different programs. (Hepatology 1995; 22:1379-1386).
Choline deficiency: A cause of hepatic steatosis during parenteral nutrition that can be reversed with intravenous choline supplementation
Authors: Buchman Alan L. , Dubin Mark D. , Moukarzel Adib A. , Jenden Donald J. , Roch Margareth , Rice Kathleen M. , Gornbein Jeff , Ament Marvin E.
Published: March 2007

Patients receiving long-term total parenteral nutrition (TPN) develop hepatic steatosis as a complication. Our previous studies have shown this to be caused, at least in part, by choline deficiency. We studied four patients (1 man, 3 women) aged 50 ± 13 years who had low plasma-free choline concentrations 4.8 ± 1.7 (normal, 11.4 ± 3.7 nmol/mL). The patients had received TPN for 9.7 ± 4.7 years. They received parenteral nutrition solutions containing choline chloride (1 to 4 g/d) for 6 weeks. Abdominal computed tomography (CT) was performed at baseline, biweekly during the choline supplementation, and 4 weeks after discontinuation of choline. During choline administration, the plasma-free choline concentration increased into the normal range within 1 week in all four patients and remained at or above the normal range for all 6 weeks, but decreased back to baseline when choline supplementation was discontinued. Hepatic steatosis resolved completely, as estimated by CT. Liver density increased from −14.2 ± 22.3 Hounsfield units (HU) to 8.4 ± 10.3 HU at week 2 (P = .002); 9.6 ± 10.7 HU at week 4 and 13.1 ± 7.3 HU at week 6, as determined by the liver-spleen CT number difference obtained by the subtraction of the average spleen CT number (in HU) from the average liver CT number. This improvement continued up to 4 weeks after choline supplementation (13.8 ± 2.8 HU). Hepatic steatosis was shown to have recurred in one patient after 10 weeks of return to choline-free parenteral nutrition. The hepatic steatosis associated with parenteral nutrition can be ameliorated, and possibly prevented, with choline supplementation. Therefore, choline may be an essential nutrient for patients who require long-term parenteral nutrition. (Hepatology 1995; 22:1399-1403).
Primary sclerosing cholangitis in 32 children: Clinical, laboratory, and radiographic features, with survival analysis
Authors: Wilschanski Michael , Chait Peter , Wade Judy A. , Davis Lori , Corey Mary , Louis Patrick St. , Griffiths Anne M. , Blendis Laurence M. , Moroz Stanley P. , Scully Linda , Roberts Eve A.
Published: March 2007

The clinical presentation and outcome of 32 children with primary sclerosing cholangitis (PSC) are reviewed, the largest North American series. The majority of patients were diagnosed in their second decade (median age: 13 years). Four children presented before the age of 2 years, but none in the neonatal period. Seventeen patients had inflammatory bowel disease (IBD), all with colitis, 14 ulcerative colitis, and 3 Crohn’s disease. Eight patients presented with chronic liver disease before clinical onset of IBD. Only 8 of 32 patients were jaundiced at presentation. Fifteen of 32 had a normal serum alkaline phosphatase (ALP) level at presentation. Nine children presented with features similar to those of autoimmune hepatitis. Cholangiography was performed in all cases and classified by a scoring system specifically developed for pediatric patients. Intrahepatic disease predominated; in only three cases a common bile duct stricture was identified requiring stenting. Findings on the initial liver biopsy were classified according to Ludwig’s criteria for staging PSC: there were 15 biopsies in stages 1 to 2 and 17 biopsies stages 3 to 4. HLA class I and II antigens were determined in 27 patients. An increased incidence of HLA B8 and DR2(15) but not DRw52a (DRB3*0101) was found. Anti-neutrophil cytoplasmic antibody (ANCA) was positive in 10 of 24 patients tested. Survival analysis indicated that a later age at presentation, splenomegaly, and prolonged prothrombin time (PT) at presentation were significant contributors to the prediction of poor outcome (i.e., death or listing for transplantation). Liver transplantation was successfully performed in seven children. Physicians must maintain a high index of suspicion of PSC in any child or young adult presenting with chronic liver disease, especially in the presence of IBD, even with a normal serum alkaline phosphatase level. (Hepatology 1995; 22:1415-1422).
Inhibition of nitric oxide synthesis in the forearm arterial bed of patients with advanced cirrhosis
Authors: Campillo Bernard , Chabrier Pierre-Etienne , Pelle Gabriel , Sediame Said , Atlan Guy , Fouet Paul , Adnot Serge
Published: March 2007

Increased vascular production of nitric oxide (NO) may contribute to the peripheral vasodilation and hyperdynamic state complicating advanced liver cirrhosis. In this study, we examined the effect on forearm blood flow of local brachial artery infusion of noradrenaline (NA) and NG-monomethyl-l-arginine (l-NMMA), an inhibitor of NO-synthase, in 10 alcoholic ascitic cirrhotic patients (patients with decompensated alcohol-induced liver disease: DALD group) and 10 patients with well-compensated alcohol-induced liver disease (CALD group). Forearm blood flow was measured by venous occlusion plethysmography. As compared with the CALD group, the DALD group had higher cardiac index and forearm blood flow as well as lower systemic blood pressure and vascular resistance. Infusions of NA and l-NMMA produced similar reduction in resting blood flow in the CALD group. However, in the DALD group, NA was significantly less effective than l-NMMA. The forearm vasoconstrictor response to NA was also significantly reduced in the DALD group when compared with the CALD group. In the DALD group, NA decreased forearm blood flow by 21.0 ± 6.2% and increased vascular resistance by 37.2 ± 12.3%, whereas respective changes in the CALD group were 41.8 ± 6.2% (P < .01) and 77.8 ± 9.9% (P < .02). In contrast, l-NMMA induced greater forearm vasoconstriction in the DALD group than in the CALD group. In decompensated patients, l-NMMA decreased forearm blood flow by 50.4 ± 2.7% and increased vascular resistance by 115.9 ± 14.4%, whereas changes in compensated patients were 38.2 ± 4.9% (P < .05) and 77.4 ± 16.2% (NS), respectively. These results are consistent with the hypothesis that increased vascular synthesis of NO contributes to the high dynamic state of patients with advanced cirrhosis. (Hepatology 1995; 22: 1423-1429).
Role of defective monocyte interleukin-10 release in tumor necrosis factor-alpha overproduction in alcoholic cirrhosis
Authors: le Moine Olivier , Marchant Arnaud , de Groote Donat , Azar Camille , Goldman Michel , Devière Jacques
Published: March 2007

Monocytes of patients with alcoholic cirrhosis produce higher amounts of tumor necrosis factor-alpha (TNF-α) after lipopolysaccharide (LPS) stimulation. The mechanisms of this overproduction remain undefined. IL-10 (IL-10) is an antiinflammatory cytokine known to downregulate TNF-α secretion by monocytes. The present study analyzes IL-10 production by monocytes and its control on TNF-α secretion in alcoholic cirrhosis. LPS-stimulated monocytes from alcoholic cirrhotics (n = 13) showed decreased IL-10 (median, 240 pg/mL [40 to 500] v 513 pg/mL [152 to 1,335]; P = .008) contrasting with increased TNF-α secretion (18,120 pg/mL [2,500 to 46,200] v 8,100 pg/mL [4,400 to 14,580]; P = .01) compared with controls (n = 13). Cells from cirrhotic patients were normally responsive to recombinant IL-10, which induced a dose dependent decrease of TNF-α secretion. On the other hand, preincubation with anti-IL-10 monoclonal antibodies led to significant increase in TNF-α secretion in controls (median, 7,325 to 16,800 pg/mL; P = .002) but not in cells from cirrhotic patients (18,535 to 20,450 pg/mL; P = .14), abolishing the difference in TNF-α production between cirrhotic patients and controls. It is concluded that defective IL-10 secretion by monocytes from alcoholic cirrhotic patients could be involved in the characteristic TNF-α overproduction observed in this disease. (Hepatology 1995; 22:1436-1439).
Abnormal expression of PDC-E2 on the apical surface of biliary epithelial cells in patients with antimitochondrial antibody-negative primary biliary cirrhosis
Authors: Tsuneyama Koichi , van de Water Judy , van Thiel David , Coppel Ross , Ruebner Boris , Nakanuma Yasuni , Dickson Rolland E. , Gershwin Eric M.
Published: March 2007

The presence of antimitochondrial antibodies (AMA) is a major criterion for the diagnosis of primary biliary cirrhosis (PBC). Although it is not clear that AMA are involved in the pathogenesis of the disease, the study of these autoantibodies has enabled much information to be accumulated about the specificity of this response. The autoantigens have been identified as components of a functionally related enzyme family, the 2-oxo-acid-dehydrogenase complex. Within this complex, pyruvate dehydrogenase E2 subunit (PDC-E2) has been determined to be the immunodominant autoantigen. Using a panel of mouse monoclonal antibodies and human combinatorial autoantibodies, it has been demonstrated that patients with PBC, but not controls, have an abnormal expression of either PDC-E2 or a cross-reacting molecule in the apical region of biliary epithelium. Others have shown a similar reaction using rabbit sera directed to PDC-E2. Our previous studies have concentrated on AMA-positive patients. In this study, the presence of PDC-E2, class II, immunoglobulin (Ig) A, and B7/BB1 in the bile duct epithelial cells of AMA-positive as well as AMA-negative patients is addressed. Most patients with AMA-negative PBC (seven of nine) react in a fashion similar to AMA-positive patients with intense staining of the apical region of the bile duct epithelial cells for “PDC-E2,” increased IgA expression, and little major histocompatibility complex (MHC) class II staining in the early-stage patients. Interestingly, the two AMA-negative patients that did not express PDC-E2 on the apical side of their biliary epithelium had anticentromere antibodies and Sjögren’s syndrome. Based on these data, it can be concluded that the disease process for both AMA-positive and AMA-negative patients with PBC has a similar pathogenic mechanism, which is likely to involve the abnormal expression of PDC-E2 or a molecular mimic of PDC-E2, and does not require MHC class II expression. (Hepatology 1995; 22:1440-1446).
Vitamin E therapy of acute CCl4-induced hepatic injury in mice is associated with inhibition of nuclear factor kappa B binding
Authors: Liu Shu-Ling , Esposti Silvia Degli , Yao Tony , Diehl Anna Mae , Zern Mark A.
Published: March 2007

Oxidative stress, with reactive oxygen intermediate formation, may represent a common mechanism by which liver injury is induced by diverse etiologies. Oxidative stress enhances nuclear factor kappa B (NF-κB) activity, and NF-κB activity has been shown to enhance the expression of cytotoxic cytokines. Acute hepatic injury caused by reactive oxygen intermediate production was induced by an intraperitoneal injection of CCl4 in mice. This injury was significantly inhibited by intravenous pretreatment of the mice with a water-soluble emulsion of α-tocopherol. Alpha-tocopherol treatment of the mice given the CCl4 also reduced the NF-κB binding to levels approaching those found in normal mice. In vitro treatment of a monocyte/macrophage cell line with CCl4 led to enhanced NF-κB binding and an increase in tumor necrosis factor-α (TNF-α) messenger RNA levels. Liver specimens taken from patients with acute fulminant hepatitis had markedly increased NF-κB binding activity in comparison with the binding of normal livers. These data demonstrate that abolishing acute hepatic injury with α-tocopherol, a free radical scavenger, also eliminated increased NF-κB binding. It is tempting to speculate that enhanced NF-κB expression caused by free radical production/oxidative stress may modulate liver injury, perhaps through an effect on cytotoxic cytokine synthesis. (Hepatology 1995; 22:1474-1481).
Specific targeting of adriamycin conjugates with monoclonal antibodies to hepatoma associated antigens to intrahepatic tumors in athymic mice
Authors: Adler Ruth , Hurwitz Esther , Wands Jack R. , Sela Michael , Shouval Daniel
Published: March 2007

Doxorubicin (adriamycin), once considered the treatment of choice for hepatocellular carcinoma (HCC), is known to cause cardiotoxicity and myelotoxicity. To reduce the systemic toxicity of adriamycin by direct delivery of the drug to the tumor site, we established a panel of monoclonal antibodies (MAbs) to hepatoma associated antigens that were conjugated to adriamycin by a dextran bridge. Initially, the efficacy of these conjugates in suppressing tumor growth was assessed using a model of subcutaneous HCC tumors injected in athymic mice. In the second stage of the study, we tested these conjugates in an experimental model in which human HCC was transplanted intrahepatically by intrasplenic injection, thus providing the tumor cells with growth factors and an adequate cellular matrix, similar to the natural microenvironment of HCC. Anti-tumoral therapy resulted in lower serum alpha-fetoprotein (AFP) levels in two of three experimental groups treated with different specific conjugates as compared with control mice treated with the individual components. Efficacy of targeting was enhanced using the intrahepatic model system for propagation of HCC and was demonstrated by fluorescence of adriamycin and MAb in tumor tissue and absence of this fluorescence in healthy liver tissue surrounding the tumor. Reduction of systemic toxicity was shown by the absence of adriamycin fluorescence in myocardial tissue in conjugate-treated mice, whereas in all other treatment groups, including mice treated with a mixture of adriamycin and specific MAb, there was strong myocardial fluorescence of adriamycin. (Hepatology 1995; 22:1482-1487).
Nitric oxide donor prevents hepatic and systemic perfusion decrease induced by endotoxin in anesthetized rabbits
Authors: Pastor Catherine M. , Losser Marie-Reine , Payen Didier
Published: March 2007

Controversial studies have been published concerning the role of nitric oxide (NO) release (beneficial or deleterious) during sepsis. Severe hypotension has been treated by NO inhibitors in humans, but animal studies described an increased mortality rate with this treatment. We hypothesized that an NO donor might be beneficial in maintaining liver flow during endotoxemia. To answer that question, mean arterial pressure (MAP), aortic, hepatic artery, and portal vein blood flow velocities (AoV, HAV, and PVV) (Doppler technique) were measured after endotoxin injection (Escherichia coli, Salmonella minnesota, and Salmonella enteritidis, 400 μg each, intravenously) in anesthetized and mechanically ventilated rabbits. Fifteen animals were treated with saline solution (10 mL/hr) or linsidomine perfusion (2 mg over 3 hours, 10 mL/hr). Saline-treated animals experienced a hypodynamic shock with a decrease in MAP, AoV, and PVV. In contrast, HAV increased without fully compensating the PVV decrease. In linsidomine-perfused rabbits, AoV and PVV remained at control level, and HAV increased without any further effect on MAP. Serum lactate levels increased in the saline-treated group and did not change in linsidomine-treated animals. These findings show that at the early phase of an endotoxin shock, and in the absence of intense fluid resuscitation, linsidomine perfusion is beneficial in maintaining systemic and hepatic perfusion while preventing lactic acidosis. These data suggest that, in the early phase of endotoxemia, NO is insufficiently released to allow adequate liver perfusion. (Hepatology 1995; 22:1547-1553).
Defective corticotropin-releasing hormone mediated neuroendocrine and behavioral responses in cholestatic rats: Implications for cholestatic liver disease-related sickness behaviors
Authors: Swain Mark G. , Maric Mirjana
Published: March 2007

Nonspecific systemic complaints are commonly encountered in patients with cholestatic liver diseases. However, the cause of these symptoms is poorly understood. Because corticotropin-releasing hormone (CRH) has been implicated as a mediator of sickness-related systemic symptoms, we examined CRH-mediated neuroendocrine and behavioral responses in rats with cholestasis due to bile duct resection (BDR) or sham resected (sham) controls. BDR and sham rats were placed individually in an open field apparatus, and the number of inner and outer squares entered, as well as the number of fecal boli produced, counted over a 5-minute period. Fecal boli production and inner squares entered are dependent on central CRH release. BDR and sham rats entered the same number of outer squares; however, BDR rats entered significantly fewer inner squares and produced fewer fecal boli than did sham rats, suggesting defective central CRH release in BDR rats. Immediately after exposure to the open field, rats were killed and blood adrenocorticotropic hormone (ACTH) levels measured. ACTH release is dependent on central CRH release. BDR rats demonstrated significantly lower plasma ACTH levels after exposure to an open field than did sham animals. To further explore the central CRH defect in BDR rats, hypothalamic CRH contents were determined in BDR and sham rats with and without exposure to restraint stress. BDR rats had significantly lower basal hypothalamic CRH levels than sham animals, and CRH levels did not further decrease in BDR rats with restraint stress (as normally occurs). These results are consistent with defective CRH-mediated responses in cholestatic rats. Aberrant CRH-mediated responses may contribute, at least in part, to some of the nonspecific systemic complaints in patients with cholestatic liver diseases. (Hepatology 1995; 22:1560-1564).
Role of heparin-binding epidermal growth factor-like growth factor as a hepatotrophic factor in rat liver regeneration after partial hepatectomy
Authors: Kiso Shinichi , Kawata Sumio , Tamura Shinji , Higashiyama Shigeki , Ito Nobuyuki , Tsushima Hirofumi , Taniguchi Naoyuki , Matsuzawa Yuji
Published: March 2007

Several growth factors including hepatocyte growth factor (HGF) have been implicated in the regulation of liver regeneration. Recently, we reported that heparinbinding epidermal growth factor (EGF)-like growth factor (HB-EGF) has hepatotrophic effects in vitro. We investigated the role of HB-EGF as a hepatotrophic factor in regenerating rat liver after 70% partial hepatectomy. The level of HB-EGF messenger RNA (mRNA) in regenerating rat liver increased 1.5 hours after partial hepatectomy and reached a maximum (about sevenfold over normal) at 6 hours. In contrast, hepatic HGF mRNA levels increased at 12 hours and achieved maximal expression at 24 hours. HB-EGF protein expression increased about 2.8-fold over normal at 10 hours after partial hepatectomy. The number of EGF receptors, to which HB-EGF binds, decreased 6 hours after partial hepatectomy. HB-EGF mRNA levels increased in nonparenchymal cells (NPCs) at 6 hours after partial hepatectomy but not in hepatocytes. Using the reverse transcription-polymerase chain reaction (RT-PCR), HB-EGF gene expression was increased predominantly in Kupffer cells and sinusoidal endothelial cells but not in lipocytes and hepatocytes. These results indicated that HB-EGF may be an important growth factor, produced in an earlier phase rather than HGF, in the regenerating liver after partial hepatectomy by a paracrine mechanism. (Hepatology 1995; 22:1584-1590).
Endothelin and vascular reactivity in cirrhosis
Authors: Sieber Cornel C.
Published: March 2007

Background/Aims:

Because the vasodilator nitric oxide is overproduced in cirrhosis, this substance may decrease pressor responses to the vasoconstrictor endothelin 1. This study aimed to examine the effects of a NO synthesis inhibitor (N
G-nitro-l-arginine methyl ester; l-NAME) on vascular responsiveness to endothelin 1 in normal and cirrhotic rats.

Methods:

Pressor dose-response curves to endothelin 1 (0.5, 1, 3, 6, and 10 μg/kg intravenously) were obtained in animals with or without pretreatment with l-NAME.

Results:

Pressor responses to endothelin 1 alone were significantly lower in cirrhotic than in normal rats. In cirrhotic animals, pressor responses to 3, 6, and 10 μg/kg of endothelin 1 were significantly higher in the presence than in the absence of l-NAME. The responses to the other doses of endothelin 1 were not affected by l-NAME. In normal rats, pressor responses to all doses of endothelin 1 were significantly higher in the presence than in the absence of l-NAME. In animals pretreated with l-NAME, pressor responses to 6 and 10 μg/kg of endothelin 1 did not differ between cirrhotic and normal rats, whereas responses to other doses remained lower in cirrhotic than in normal rats.

Conclusions:

In rats with cirrhosis, NO seems to contribute to vascular hyporeactivity to high doses but not to low doses of endothelin 1.
Closing in on a “familial cholestasis gene”
Authors: Wagstaff Joseph , Jonas Maureen M.
Published: March 2007

It is now feasible to map disease genes by screening the genome for linkage disequilibrium between the disease and marker alleles. This report presents the first application of this approach for a previously unmapped locus. A gene for benign recurrent intrahepatic cholestasis (BRIC) was mapped to chromosome 18 by searching for chromosome segments shared by only three distantly related patients. The screening results were confirmed by identifying an extended haplotype conserved between the patients. Probability calculations indicate that such segment sharing is unlikely to arise by chance. Searching the genome for segments shared by patients is a powerful empirical method for mapping disease genes. Computer simulations suggest that, in appropriate populations, the approach may be used to localize genes for common diseases.

A locus for progressive familial intrahepatic cholestasis (PFIC), also known as Byler disease, has been mapped to a 19 cM region of chromosome 18 by a search for shared segments, using patients from the Amish kindred in which the disorder was originally described. A similar liver disease, benign recurrent intrahepatic cholestasis (BRIC), recently has been mapped to the same region, suggesting that these two diseases are caused by mutations in the same gene. Although PFIC and BRIC are clinically distinct diseases, episodic attacks of jaundice and pruritus, with elevated concentrations of bile acid in serum, are seen in both disorders. In PFIC patients, these attacks result in progressive liver damage and death. The clinical and biochemical features of PFIC and BRIC are suggestive of a defect in primary bile acid secretion. The biology of bile secretion is of great interest because of its vital importance in digestion of dietary fats as well as in secretion of xenobiotics and metabolic waste products. Cloning of the gene (or genes) responsible for PFIC and BRIC will likely provide important insights into this pathway. (Reprinted by permission of Oxford University Press).
Transjugular intrahepatic portosystemic shunt: Is it the ultimate solution for refractory ascites?
Authors: Wong Florence , Blendis Laurence
Published: March 2007

Background.

Previous studies have suggested that the transjugular placement of an intrahepatic stent to establish a portosystemic shunt is an effective treatment of uncomplicated ascites accompanying variceal bleeding. We studied the stent shunt for use in patients with liver cirrhosis and ascites refractory to medical treatment.

Methods.

Fifty of 62 consecutive patients with cirrhosis and refractory ascites were treated with the stent shunt-an expandable stent of metallic mesh placed between a major branch of the portal vein and one of the hepatic veins. Patients were followed for a mean (±SD) of 426 ± 333 days.

Results.

The stent shunt was successfully placed in all patients and reduced the pressure gradient between the portal vein and the inferior vena cava by an average of 63 percent. Thirty-seven patients (74 percent) had complete responses (total remission of ascites within three months), and nine patients (18 percent) had partial responses. Four patients did not respond, including two who died within two weeks of shunt placement. After the procedure, 25 patients had hepatic encephalopathy, as compared with 20 patients before the procedure; although encephalopathy improved in 3 patients, new encephalopathy developed in 8 patients. In the 28 of the 33 patients followed for more than six months who were evaluated, the mean serum creatinine concentration was 1.5 ± 0.09 mg per deciliter (133 ± 8 μmol per liter) before placement of the stent shunt, 1.5 ± 1.6 mg per deciliter (133 ± 141 μmol per liter) one week after the procedure, and 0.9 ± 0.3 mg per deciliter (80 ± 27 μmol per liter) after six months (P = 0.008 for the comparison of concentrations before and six months after the procedure). Renal function did not improve in the six patients with organic kidney disease. Procedure-related complications developed in 16 patients. During follow-up, an additional 29 patients died-10 of progressive liver disease and 19 of other causes. Survival for at least one year was associated with a patient’s being under 60 years of age, having a serum bilirubin level before placement of the stent shunt of less than 1.3 mg per deciliter (22 μmol per liter), and having a complete response.

Conclusions.

Our findings in an uncontrolled prospective study suggest that the transjugular intrahepatic porto-systemic stent-shunt procedure was an effective treatment for many patients with liver cirrhosis and refractory ascites, but mortality from underlying diseases was substantial. (N Engl J Med 1995; 332:1192-7. Copyright 1995. Massachusetts Medical Society. All rights reserved).
Hepatitis B virus infection: Precore mutants and its relation to viral genotypes and core mutations
Authors: Rodriguez-Frias Francisco , Buti Maria , Jardi Rosendo , Cotrina Montserrat , Viladomiu Luis , Esteban Rafael , Guardia Jaime
Published: March 2007

The precore-core gene of hepatitis B virus (HBV) was directly sequenced from serum samples of 42 patients with chronic B hepatitis (19 hepatitis B e antigen [HBeAg]+ and 23 anti-HBe+). Viral genotypes were determined by comparison with 11 reference sequences and by restriction analysis. Genotype A was identified in 16 cases, genotype D in 24 cases, and other genotypes in 2 cases. Precore mutations, mainly M1 (stop at codon 28), were differently distributed among the viral genotypes: 3 cases (18.8%) with genotype A and 18 cases (75%) with genotype D. In sequences with precore mutants, the encapsidation signal was more stable (negative stabilization energy) than in sequences without precore mutants. In genotype A, the M1 mutation coexisted with a second mutation (C → T at position 1858 in codon 15), and both mutations were paired in the secondary structure of the RNA encapsidation signal, which justified the rare presence of precore mutants in this genotype. The analysis showed different distribution of mutations depending on the viral genotype; patients with genotype D were more likely to have persistent HBV infection by selection of precore mutants. Multiple amino acid substitutions were detected in the core region, mainly in two subsequences that have been previously described as epitopes (flanked by codons 11 to 27 and 74 to 83); the presence of these mutations was significantly related to the presence of precore variants which abolished the expression of HBeAg. The study of viral genotypes in chronic HBV infection may be valuable in predicting the persistence of viral replication after seroconversion to anti-HBe and suggest that the outcome of chronic infection may be affected by the HBV variability. (Hepatology 1995; 22:1641-1647).