bluuebunny/crossref_metadata_2025 huggingface dataset:
Natural fluctuations of hepatitis C viral load in a homogeneous patient population: A prospective study
Authors: Fanning Liam , Kenny-Walsh Elizabeth , Levis John , Choudhury Kingshuk Roy , Cannon Bridin , Sheehan Margaret , Whelton Michael , Shanahan Fergus
Published: July 2004

The aim of this study was to determine the variation in hepatitis C viral load over an extended period of patient follow up. Serum samples were collected from 49 female individuals who were identified as having been infected from the same source of hepatitis C-contaminated anti-D immunoglobulin during the period from 1977 (May) to 1978 (November). All patients attended the hepatitis C clinic at Cork University Hospital, Cork, Ireland. The study group was homogeneous with respect to gender, hepatitis C virus (HCV) genotype (1b), and duration of infection. None of the patients had received antiviral therapy at the time of completion of study. Viral load quantifications were assessed using the Roche Monitor (F. Hoffmann-La Roche, Ltd., Basel, Switzerland) assay. The mean age of the study group at time of infection was 30.3 years (SD ± 6.1) with a range from 18.5 to 43 years. The mean time of follow-up was 4.1 years (SD ± 1.0) with a range from 1.2 to 5 years. The mean rate of change of viral load per year was 0.23 log10 viral copies per mL serum for the study group (SD ± 0.19) with a range of −0.18 to 0.78 that was significantly different from zero, P < 10−10. The rate of change of viral load per year was negatively correlated with viral load at first determination, r = −.35, P = .01. Age at infection did not correlate with the slope of change of viral load, P = .10. In conclusion, most women infected with HCV 1b will have an increase in viral load over time but a few patients who acquire infection early in adult life will show a decrease in viral load.
Progressive development of a Th1-type hepatic cytokine profile in rats with experimental cholangitis
Authors: Tjandra Kartika , Sharkey Keith A. , Swain Mark G.
Published: July 2004

Primary biliary cirrhosis (PBC) and primary sclerosing cholangitis (PSC) are presumed autoimmune chronic cholestatic liver diseases characterized by cholangitis and progressive loss of bile ducts. Cytokines have been postulated to be involved in the progression of these diseases, but their role is poorly defined. Our objectives were to characterize a rat model of cholangitis and to determine Type 1/Type 2 (Th1/Th2) cytokine profile shifts in this model. Cholangitis was induced in Sprague-Dawley rats (200 to 225 g) by low-dose oral administration of the biliary toxin α-naphthylisothiocyanate (ANIT) (1 g/kg powdered rat chowad libitum) for 4, 7, and 14 days. Cholestasis was observed in ANIT-treated animals. Liver histology of ANIT-treated rats showed hepatic inflammation centered on damaged bile ducts, significant bile duct proliferation, and progressive fibrosis. Immunohistochemistry showed enhanced staining of hepatic major histocompatibility complex (MHC) II, CD4, and CD8 in portal areas of ANIT-treated animals. In addition, the hepatic cytokine profile became increasingly Th1 in nature with progressive ANIT treatment. In summary, experimental cholangitis biochemically and histologically mimics human chronic cholangitis and furthermore, is associated with a progressive shift to a more Th1-dominant hepatic cytokine profile. Therefore, this model may be useful for examining the role of cytokines in the progression of chronic cholangitic diseases.
Increased activity of guanosine 3′-5′-cyclic monophosphate phosphodiesterase in the renal tissue of cirrhotic rats with ascites
Authors: Angeli Paolo , Jiménez Wladimiro , Veggian Rosalia , Fasolato Silvano , Volpin Roberta , MacHenzie Harald S. , Craighero Raffaella , Dalla Libera Virna , Sticca Antonietta , Arroyo Vicente , Gatta Angelo
Published: July 2004

A possible defect of guanosine 3′-5′-cyclic monophosphate (cGMP) content in the renal tissue caused by an increased activity of cGMP phosphodiesterase (PDE) has, so far, not been evaluated in the pathogenesis of renal resistance to endogenous natriuretic peptides (ENP) in cirrhosis with ascites. To test this hypothesis the activity of cGMP-PDE and the concentration of cGMP were evaluated in vitro in the renal tissue of 10 control rats and 10 cirrhotic rats with ascites before and after the intravenous (IV) administration of Zaprinast (Sigma, St. Louis, MO), a specific cGMP-PDE inhibitor (30 μg/kg/min). Moreover, the effects of the intravenous administration of Zaprinast (15 μg/kg/min and 30 μg/kg/min) on renal plasma flow (RPF), glomerular filtration rate (GFR), and urinary sodium excretion (UNaV) were evaluated in 10 conscious control rats and 10 conscious cirrhotic rats with ascites. The effects of Zaprinast on plasma renin activity (PRA) was also evaluated in 10 control rats and in 10 cirrhotic rats with ascites. Finally, the effect of Zaprinast on RPF, GFR, and UNaV were evaluated in 10 cirrhotic rats after the IV administration of the ENP-receptor antagonist, HS-142-1. The renal content of cGMP was reduced in cirrhotic rats because of increased activity of cGMP-PDE. Zaprinast inhibited cGMP-PDE activity and increased the renal content of cGMP in these animals. The inhibition of cGMP-PDE was associated with an increase in RPF, GFR, and UNaV and a reduction in PRA. HS-142-1 prevented any renal effect of Zaprinast in cirrhotic rats. In conclusion, an increased activity of the cGMP-PDE in renal tissue contributes to the renal resistance to ENP in cirrhosis with ascites.
Cost-effectiveness of different strategies of cytomegalovirus prophylaxis in orthotopic liver transplant recipients
Authors: Das Ananya
Published: July 2004

Cytomegalovirus (CMV) is an important cause of morbidity and mortality in liver transplant recipients and several different strategies of CMV chemoprophylaxis are in practice. A cost-effective analysis was performed to compare these strategies. A hypothetical cohort of liver transplant recipients was followed up for a year posttransplantation in a Markov model, as they made possible transitions to different states of health with respect to CMV infection and disease. Different strategies of chemoprophylaxis were compared. Cost per patient, yield in terms of gain in quality-adjusted stages, amount of time spent in the state of CMV disease, and CMV-related mortality were the outcome measures compared. Oral ganciclovir administered universally to all transplant recipients was the most favored strategy. Restricting prophylaxis to defined high-risk groups or extending the duration of prophylaxis beyond 3 months did not improve cost-effectiveness. The strategy of short-term, oral ganciclovir-based chemoprophylaxis for CMV in liver transplant recipients is cost-effective by current standards of healthcare interventions.
Oral budesonide in the treatment of patients with primary biliary cirrhosis with a suboptimal response to ursodeoxycholic acid
Authors: Angulo Paul , Jorgensen Roberta A. , Keach Jill C. , Dickson Rolland E. , Smith Coleman , Lindor Keith D.
Published: July 2004

Ursodeoxycholic acid (UDCA) is a safe and effective medical therapy for most patients with primary biliary cirrhosis (PBC). However, some patients show an incomplete response to UDCA therapy. Treatment with corticosteroids may be of benefit although at the expense of systemic side effects. Budesonide, a corticosteroid with an extensive first-pass hepatic metabolism appeared promising for the treatment of PBC. The aim of this study was to evaluate the safety and estimate the efficacy of budesonide in patients with PBC, who have shown a suboptimal response to UDCA. Twenty-two patients with PBC, 16 women, median age of 50 who had been on UDCA (13-15 mg/kg/d) for a mean of 46 months (range 6-108 months) and had shown a persistent elevation of alkaline phosphatase activity at least 2 times the upper limit of normal were enrolled. Oral budesonide, 9 mg daily was administered for 1 year and patients continued on the same dosage of UDCA. There was a significant, but transitory improvement in serum levels of total bilirubin (P = .001) and a significant, but marginal improvement in serum alkaline phsophatase (P = .001) with combination therapy. The Mayo risk score increased significantly (P = .02) and there was a significant loss of bone mass (P < .001) of the lumbar spine. Budesonide-induced hyperglycemia and cosmetic adverse effects were noted in 2 patients. In conclusion, oral budesonide appears to add minimal, if any, additional benefit to UDCA, and it is associated with a significant worsening of osteoporosis in patients with PBC.
Treatment of Wilson’s disease with zinc. XVII: Treatment during pregnancy
Authors: Brewer George J. , Johnson Virginia D. , Dick Robert D. , Hedera Peter , Fink John K. , Kluin Karen J.
Published: July 2004

Therapy of Wilson’s disease continues to evolve. In 1997, zinc acetate was added to the list of drugs approved by the Food and Drug Administration, which includes penicillamine and trientine. The mechanism of zinc’s anticopper action is unique. It induces intestinal cell metallothionein, which binds copper and prevents its transfer into blood. As intestinal cells die and slough, the contained copper is eliminated in the stool. Thus, zinc prevents the intestinal absorption of copper. It is universally agreed that pregnant Wilson’s disease patients should remain on anticopper therapy during pregnancy. There are numerous reports of such patients stopping penicillamine therapy to protect their fetus from teratogenicity, only to undergo serious deterioration and even death from renewed copper toxicity. Penicillamine and trientine have teratogenic effects in animals, and penicillamine has known teratogenic effects in humans. In this report we discuss the results of 26 pregnancies in 19 women who were on zinc therapy throughout their pregnancy. The evidence is good that zinc protects the health of the mother during pregnancy. Fetal outcomes were generally quite good, although one baby had a surgically correctable heart defect and one had microcephaly.(Hepatology 2000;31:364-370.)
Annexin 1 expression and phosphorylation are upregulated during liver regeneration and transformation in antithrombin iii sv40 t large antigen transgenic mice
Authors: de Coupade Catherine , Gillet Raphaëlle , Bennoun Myriam , Briand Pascale , Russo-Marie Françoise , Solito Egle
Published: July 2004

We have used a transgenic animal model, which constitutively develops hepatocarcinoma (Antithrombin III SV40 T large Antigen: ASV), to study the involvement of Annexin 1 (ANX1) in liver regeneration and malignant transformation. Primary hepatocytes isolated from normal mice did not express ANX1. In contrast, ANX1 was strongly expressed in hepatocytes of transgenic mice during constitutive development of hepatocarcinoma. In ASV transgenic mice, an elevated ANX1 level preceded the appearance of the tumor, indicating that it could be a good marker in the diagnosis of cancer. One-third hepatectomy in normal mice resulted in stimulation of ANX1 synthesis and phosphorylation. This upregulation correlated with increased synthesis of EGF and consequently with increased phosphorylation of the EGF receptor (EGF-R). Stable transfection of a hepatocyte cell line derived from ASV transgenic mice (mhAT2) with antisense complementary DNA for ANX1 reduced the proliferation rate as well as cytosolic phospholipase A2 (cPLA2) activity. Thus, ANX1 expression and phosphorylation could be a factor implicated in liver regeneration and tumorigenesis, either through modulation of cPLA2 activity or EGF-R function.
Support of sinusoidal endothelial cell glutathione prevents hepatic veno-occlusive disease in the rat
Authors: Wang Xiangdong , Kanel Gary C. , DeLeve Laurie D.
Published: July 2004

Depletion of sinusoidal endothelial cell glutathione (GSH) has been proposed as a common mechanism leading to hepatic veno-occlusive disease (HVOD). This study examines whether intraportal infusion of GSH can prevent HVOD in the monocrotaline rat model. HVOD was induced in rats with monocrotaline 160 mg/kg i.g. on day 0. GSH was infused intraportally by mini-osmotic pump. Monocrotaline decreased GSH in sinusoidal endothelial cells, but not in liver homogenate. Infusion of GSH, 2 μmol/hr starting day − 1, prevented the decrease in sinusoidal endothelial cell GSH and protected against histological and clinical evidence of HVOD. Protection by GSH was dose-dependent (0.5-2 μmol/hr). In rats receiving continuous GSH infusion, treatment with buthionine sulfoximine starting day − 2 decreased sinusoidal endothelial cell GSH and attenuated the protective effect of GSH against monocrotaline. GSH infusion starting 24 hours after monocrotaline (“glutathione rescue”) offered substantial protection to most rats. N-acetyl-l-cysteine conferred protection, but N-acetyl-d-cysteine (an antioxidant that is not a precursor for GSH) had little or no protective effect, and 4-hydroxy TEMPO, a free radical scavenger, was not protective. Discontinuation of the GSH infusion 5 days after monocrotaline administration led to severe hepatic veno-occlusive disease on day 6. In conclusion, monocrotaline selectively depletes sinusoidal endothelial cell GSH. Intraportal infusion of GSH protects against monocrotaline toxicity, at least partially by maintaining sinusoidal endothelial cell GSH levels. Glutathione infusion started after monocrotaline is partially protective. Monocrotaline induces prolonged changes in the liver that remain suppressed as long as GSH is infused.
The ratio of ELR+ to ELR− CXC chemokines affects the lung and liver injury following hepatic ischemia/reperfusion in the rat
Authors: Colletti Lisa M. , Green Maranne E. , Burdick Marie D. , Strieter Robert M.
Published: July 2004

Hepatic ischemia/reperfusion (I/R) results in a neutrophil-dependent lung and liver injury. The process of neutrophil recruitment and activation in this injury is at least partially dependent on the presence of the ELR+ CXC chemokines. Other investigations have shown that ELR− CXC chemokines can block ELR+ CXC chemokine neutrophil recruitment and activation in vitro. To begin to investigate the role of the balance between these 2 types of molecules in vivo in neutrophil recruitment and activation following hepatic I/R, we used our rat model of lobar hepatic I/R and pretreated animals with pharmacologic doses of gamma-interferon (γ-IFN). γ-IFN is known to upregulate some of the ELR− CXC chemokines, including γ-IFN-inducible protein (IP-10) and monokine-induced by γ-IFN (MIG), as well as down-regulate ELR+ CXC chemokine production. Following hepatic I/R or sham laparotomy, hepatic and pulmonary levels of the ELR− chemokines, IP-10 and MIG, and the ELR+ chemokines, rat cytokine-induced neutrophil chemoattractant (KC), macrophage inflammatory protein-2 (MIP-2), and epithelial neutrophil activating protein (ENA-78) were determined by ELISA, and lung and liver injury were assessed. In response to γ-IFN, hepatic and pulmonary levels of the ELR− chemokines were increased and the levels of the ELR+ chemokines were decreased. Immunohistochemical staining confirmed the hepatocyte as the source of these molecules, as well as the changes in chemokine levels in response to γ-IFN. There was an associated significant decrease in liver and lung injury, although there was no significant decrease in neutrophil influx in either tissue. This suggests that the alteration in the balance of ELR+ to ELR− CXC chemokines results in a decrease in tissue injury through a mechanism other than through an alteration in tissue neutrophil levels.
Phosphatidylinositol 3-kinase and protein kinase C contribute to the inhibition by interleukin 6 of phosphoenolpyruvate carboxykinase gene expression in cultured rat hepatocytes
Authors: Christ Bruno , Yazici Emine , Nath Annegret
Published: July 2004

The participation of phosphatidylinositol 3-kinase (PI3-kinase), protein kinase C, and mitogen-activated protein kinase (MAP-kinase) in the inhibition by interleukin 6 (IL-6) and insulin of phosphoenolpyruvate carboxykinase (PCK) gene expression was investigated in cultured rat hepatocytes. IL-6 or insulin inhibited the glucagon-stimulated increase in PCK messenger RNA (mRNA) by about 70%. In the presence of either the PI3-kinase inhibitor, wortmannin, or the protein kinase C inhibitor, GF109203x, the inhibition by IL-6 was only about 40%, although it was abolished with both inhibitors in combination. Wortmannin alone but not GF109203x prevented the inhibition by insulin of glucagon-stimulated PCK gene expression. The MAP-kinase pathway inhibitor, PD98059, did not affect IL-6 or insulin inhibition of PCK mRNA increase. When chlorophenylthio-cyclic 3′,5′ adenosine monophosphate (CPT-cAMP) was used instead of glucagon, IL-6 or insulin inhibited the increase in PCK mRNA by 75% and 85%, respectively. The inhibition by IL-6 was only about 50% in the presence of either wortmannin or GF109203x alone but was abolished with the combination of both inhibitors. The inhibition by insulin was only about 50% in the presence of GF109203x and was abolished by wortmannin. The inhibitors did not affect the inhibition by IL-6 or insulin of the glucagon-stimulated increase in cAMP. It is concluded that the inhibition by IL-6 of PCK gene expression involved both PI3-kinase and protein kinase C, whereas the inhibition by insulin required only PI3-kinase. The inhibition occurred downstream from cAMP formation. Hence, IL-6 and insulin may share, in part, common signal transduction pathways in the inhibition of PCK gene expression.
The cost of hepatitis A infections in American adolescents and adults in 1997
Authors: Berge Jeremy J. , Drennan David P. , Jacobs Jake R. , Jakins Alan , Meyerhoff Allen S. , Stubblefield Wayne , Weinberg Melvyn
Published: July 2004

The incidence of hepatitis A has declined in the United States for several decades, leading to an increased number of susceptible adolescents and adults. Because clinical severity increases with age, hepatitis A infections in older individuals cause greater morbidity, mortality, and treatment costs. Because the economic burden of hepatitis A has not been well described, we estimated its costs, from the societal perspective, for patients infected at distinct ages. A case-series study described treatment patterns, work loss, and symptom duration. Disease outcomes were estimated by an expert panel. Economic losses were calculated by applying normative data reflecting treatment charges, employee compensation, and the value of housekeeping services. In the case-series study, mean treatment charges were $740 for nonhospitalized patients versus $6,914 for hospitalized patients (P < .001). Symptom duration (67.8 vs. 34.4 days, P < .001) and work loss (33.2 vs. 15.5 days, P < .01) were also greater for those hospitalized. Nationally, we estimate 63,363 symptomatic hepatitis A infections occurred among adolescents and adults during 1997, resulting in 8,403 hospital admissions and 255 deaths. Nearly 2.5 million days of symptomatic illness and 829,000 work-loss days resulted, and 7,466 years of life were lost. Under base-case assumptions, annual hepatitis A costs were estimated at $488.8 million. In sensitivity analyses, this estimate varied from $332.4 to $579.9 million. These costs may be reduced by regionally targeted vaccination of children, as recommended by the Advisory Committee on Immunization Practices, although the cost effectiveness of this policy has not yet been established.
T(14;18) translocation in chronic hepatitis C virus infection
Authors: Zignego Anna Linda , Giannelli Francesca , Marrocchi Maria Eugenia , Mazzocca Antonio , Ferri Clodoveo , Giannini Carlo , Monti Monica , Caini Patrizio , Villa Giorgio La , Laffi Giacomo , Gentilini Paolo
Published: July 2004

Pathogenic mechanisms of B-cell lymphoproliferative disorders in chronic hepatitis C virus (HCV) infection are unclear. We studied t(14;18) translocation by polymerase chain reaction in peripheral blood mononuclear cells from 50 patients with HCV-related liver disease (group A), 7 with mixed cryoglobulinemia syndrome (group B), 55 with HCV-negative liver disease (group C), and 30 with HCV-negative chronic rheumatic disorders or chronic infection by nonhepatotropic agents (group D). T(14;18) was significantly more frequent in group A (13/50 patients = 26 %) and group B (5/7 = 71.4%) patients than in group C (1/55 = 3.6%) and group D (1/30 = 3.3%) ones. Immunoblot analysis showed bcl-2 over-expression in all t(14;18)-positive samples. In group A, 10/13 (77%) patients with t(14;18) and 13/37 (35%) without t(14;18) had serum cryoglobulins in the absence of mixed cryoglobulinemia symptoms (P < .05). These data indicate that t(14;18) and bcl-2 over-expression in lymphoid cells are frequent in chronic HCV infection and suggest that this event may contribute to the pathogenesis of HCV-related lymphoproliferative disorders.
Reduced hepatitis B virus surface antigen-specific Th1 helper cell frequency of chronic HBV carriers is associated with a failure to produce antigen-specific antibodies in the Trimera mouse
Authors: Böcher Wulf Otto , Galun Eithan , Marcus Hadar , Daudi Nili , Terkieltaub Dov , Shouval Daniel , Löhr Hanns Friedrich , Reisner Yair
Published: July 2004

In chronic hepatitis B virus (HBV) infection weak antiviral immune responses are associated with viral persistence. We studied possible immune deficits underlying the lack of serum antibodies of such patients against the HBV surface antigen (HBsAg) in a novel human/mouse chimeric model. A hepatitis B surface antigen (HBs) vaccination of Balb/c mice engrafted with peripheral blood mononuclear cells (PBMC) of naturally HBV-immunized donors induced high frequencies of human HBsAg-specific B and T helper 1 (Th1) cells. These responses were associated with high serum anti-HBs antibody levels of the subclasses immunoglobulin G1 (IgG1) and IgG2 that are driven by interleukin-2 (IL-2) and interferon-γ (IFN-γ). In contrast, PBMC of chronic HBV carriers transplanted into the chimera failed to produce anti-HBs antibodies after vaccination with HBsAg and exhibited a deficit of antigen-specific Th1 cells. A possible influence of HBsAg or viremia was excluded by the lack of viral replication in such chimera. The observed T-cell defect was specific for HBsAg, as the B- and T-cell responses to tetanus toxoid (TT) were fully retained. Thus, our study shows that viral persistence in chronic HBV carriers is associated with an HBsAg-specific Th1 cell defect, which likely is responsible for the insufficient neutralizing anti-HBs-antibody response and is not reversed by HBs vaccination. Alternative approaches to induce HBs-specific Th1 cell responses might represent a future therapeutic option.
Latent hepatitis B virus infection in healthy individuals with antibodies to hepatitis B core antigen
Authors: Marusawa Hiroyuki , Uemoto Shinji , Hijikata Makoto , Ueda Yoshihide , Tanaka Koichi , Shimotohno Kunitada , Chiba Tsutomu
Published: July 2004

Several recent reports have shown that hepatitis B virus (HBV) could be frequently transmitted to the recipients from donors who have antibodies to hepatitis B core antigen (anti-HBc) through liver transplantation. We provide here the molecular evidence of latent HBV infection accompanied with ongoing viral replication in the liver tissue of anti-HBc-positive healthy individuals. HBV DNA was detectable in 13 of 14 healthy donors who were positive for both anti-HBc and antibodies to hepatitis B surface antigen (anti-HBs), but in none of 3 who were positive for anti-HBs alone. The detected HBV genomes from these subjects included covalently closed circular DNA and pregenomic RNA, the replication intermediate of HBV. Notably, 5 of 7 cases tested were predominantly infected with wild type HBV strains without any mutations in the precore and core promoter regions under the presence of circulating antibody to hepatitis B e antigen. Interestingly, a predominant clone detected in one donor showed a 63-nucleotide deletion in the precore region including an encapsidation signal sequence. Our findings indicate that the majority of healthy individuals positive for anti-HBc, which had been assumed to denote a past history of transient HBV infection, were latently infected with the episomal form of HBV accompanied by ongoing viral replication and few nucleotide mutations in the precore and core regions.
Pilot study of combination therapy with ribavirin and interferon alfa for the retreatment of chronic hepatitis B e antibody-positive patients
Authors: Cotonat Teresa , Quiroga Juan Antonio , López-Alcorocho Juan Manuel , Clouet Rosa , Pardo Margarita , Manzarbeitia Félix , Carreño Vicente
Published: July 2004

Twenty-four patients with chronic hepatitis B virus (HBV), antibody to hepatitis B e antigen (anti-HBe), HBV DNA positivity, and alanine transaminase (ALT) elevation who failed previous interferon alfa (IFN-α) therapy were included in a pilot study of combination therapy with ribavirin and IFN-α. The patients received daily oral ribavirin (1,000-1,200 mg according to body weight) plus 5 million units (MU) IFN-α2b three times a week for 12 months and were followed-up for 12 months. The median viremia level decreased significantly at the end of treatment (1.2 × 103copies/mL) and follow-up (4.0 × 102 copies/mL) compared with the baseline (3.0 × 106 copies/mL; P < .05). After 12 months, 8 of 24 (33%) patients had cleared HBV DNA and 12 (50%) had normal ALT levels. At the end of the study virological and biochemical response was 50% and 21%, respectively. Thus, virological and biochemical response sustained in 5 of 24 (21%) patients retreated with ribavirin and IFN-α; none of them lost hepatitis B surface antigen (HBsAg). Liver histology improved in 2 of 4 sustained responders but in none of the 12 nonresponders with paired biopsies (P = .05). The response was independent of dose and duration of previous treatment, viral load, or the distribution of HBV precore wild-type/mutant variants. However, sustained responders had significantly higher necroinflammation (P = .036) and fibrosis (P = .007) scores. IFN-α-related side effects were mild and reversible on discontinuation. In 4 (17%) patients who suffered nausea and diarrhea the ribavirin dosage was reduced by 50% after 1 month of therapy and finally discontinued in all of them. No patient had liver disease decompensation. In summary, combination therapy with ribavirin and IFN-α may be efficacious to treat viremic anti-HBe-positive patients with chronic hepatitis B who have failed previous IFN therapy.
Sodium, Hydrogen exchange type 1 and bile ductular secretory activity in the guinea pig
Authors: Hübner Christian , Stremmel Wolfgang , Elsing Christoph
Published: July 2004

Biliary epithelial cells (BECs) express different Na+, H+ exchange (NHE) isoforms. In this study, the potential role of NHE in ductular bile secretion is assessed. Experiments were performed in guinea pig perfused livers and isolated BECs. Inhibition of NHE was achieved by hypotonic stress and by using the unspecific NHE inhibitor, amiloride, or the specific NHE 1 inhibitor, cariporide (HOE 642). Hypotonic stress inhibited basal bile flow by 46% and prevented secretin stimulation of bile flow by reducing biliary bicarbonate output by 50%. Secretin increased bile flow from 3.7 ± 0.8 μL/min/g to 4.78 μL/min/g (P < .01); subsequent exposure to hypotonic stress decreased secretin-stimulated bile flow by 35% and biliary bicarbonate secretion by ˜50%. Inhibition of NHE by amiloride or cariporide resulted in a similar reduction of secretin-stimulated bile flow and bicarbonate secretion. Basal bile flow was unaffected by the NHE inhibitors. In isolated guinea pig BECs, regulatory volume decrease and inhibition of NHE was demonstrated after hypotonic stress under basal and secretin-stimulated conditions. In contrast, hypotonic exposure inhibited Cl−, HCO3
− exchange activity in isolated BECs only during basal conditions but incompletely after secretin stimulation. Our study shows that hypotonic stress inhibits basal bile flow in the guinea pig by inhibition of Cl−, HCO3
− exchange. NHE1 is not involved in basal bile formation. Increased choleresis after ductular stimulation by secretin depends on intact NHE1 activity. These data indicate that BEC volume changes have profound effects on biliary secretory function.
Influence of donor cardiopulmonary arrest in human liver transplantation: Possible role of ischemic preconditioning
Authors: Totsuka Eishi , Fung John J. , Urakami Atsushi , Moras Natalia , Ishii Tomohiro , Takahashi Katsuro , Narumi Shunji , Hakamada Kenichi , Sasaki Mutsuo
Published: July 2004

Hepatic allografts from donors who have suffered a brief cardiopulmonary arrest may sustain ischemic damage before organ procurement. However, there is no reported correlation between donor cardiopulmonary arrest and hepatic allograft dysfunction. On the other hand, brief ischemia-reperfusion injury has been shown experimentally to result in protection in several organ models. Induction of ischemic tolerance has been called ischemic preconditioning. Our objective was to study the influence of brief donor cardiopulmonary arrest on hepatic allograft outcome in human liver transplantation. Between May 1997 and July 1998, 181 consecutive orthotopic liver transplant (OLT) cases were divided into 2 groups based on the occurrence of donor cardiopulmonary arrest. Group A consisted of 37 donors who suffered a cardiopulmonary arrest. Group B consisted of the remaining 144 patients. Liver graft survival within 90 days of OLT and early postoperative graft function were analyzed. Although there was significant liver damage resulting from circulatory failure during cardiopulmonary arrest before organ procurement in group A, graft survival was not affected. After OLT, the mean peak aspartate transaminase and alanine transaminase concentrations in group A (1,444.1 and 718.2 U/L) were significantly lower than those in group B (2,382.8 and 1,507.3 U/L) (P < .05). Experiences of brief cardiopulmonary arrest in organ donors did not affect post-OLT hepatic allograft survival and function. Although the liver function tests are elevated in an organ donor, the hepatic allograft is suitable for OLT if the liver damage is induced by brief donor cardiopulmonary arrest.
Cause of portal or hepatic venous thrombosis in adults: The role of multiple concurrent factors
Authors: Denninger Marie-Hélène , Chaït Yasmine , Casadevall Nicole , Hillaire Sophie , Guillin Marie-Claude , Bezeaud Annie , Erlinger Serge , Briere Jean , Valla Dominique
Published: July 2004

According to a recent hypothesis, venous thrombosis results from the concurrence of several factors. This hypothesis was assessed in patients with portal or hepatic venous thrombosis by simultaneously investigating most of the currently identified prothrombotic disorders, local precipitating factors, and other risk factors such as oral contraceptive use. Patients with a tumorous obstruction and patients with cirrhosis with portal vein thrombosis were excluded. The prothrombotic disorders that were investigated included classical and occult myeloproliferative disorders; antiphospholipid syndrome; protein C; protein S and antithrombin deficiency; factor V Leiden; factor II; and methylene-tetrahydrofolate-reductase gene mutations. We found 1 or several prothrombotic disorders and a local precipitating factor in 26 and 10 of the 36 patients with portal vein thrombosis, respectively; and in 28 and none of the 32 patients with hepatic vein thrombosis, respectively. We found a combination of prothrombotic disorders in 5 and 9 patients with portal and hepatic vein thrombosis, respectively, whereas such a combination is expected in less than 1% of asymptomatic subjects. Of the 10 patients with a local precipitating factor, 8 had a prothrombotic disorder. Of the 13 patients who use oral contraceptives, 10 had a prothrombotic disorder. We conclude that portal or hepatic venous thrombosis should be regarded as an index for 1 or several prothrombotic disorders, whether or not local precipitating factors or oral contraceptive use are found. Concurrence of prothrombotic disorders is more common than expected. Extensive investigation of prothrombotic disorders and anticoagulation should be considered in patients with portal or hepatic venous thrombosis.
Insulin-like growth factor-I reverts testicular atrophy in rats with advanced cirrhosis
Authors: Castilla-Cortazar Inma , Garcia Maria , Quiroga Jorge , Diez Nieves , Diez-Caballero Fernando , Calvo Alfonso , Diaz Matias , Prieto Jesus
Published: July 2004

The pathogenesis of hypogonadism in cirrhosis is not completely understood. The levels of insulin-like growth factor-I (IGF-I), an anabolic factor with trophic actions on testes, are reduced in cirrhosis. This study was undertaken to evaluate whether rats with advanced cirrhosis develop hypogonadism and whether the administration of IGF-I exerts beneficial effects on testicular structure and function. Wistar rats with ascitic cirrhosis induced with CCl4 were allocated into 2 groups (n = 10, each) to receive recombinant IGF-I (20 μg · kg−1 · d−1, subcutaneously) or vehicle for 3 weeks. Healthy rats receiving vehicle were used as the control group (n = 10). At baseline, both cirrhotic groups showed similar deterioration of liver function tests. Compared with controls, nontreated cirrhotic rats showed decreased serum levels of IGF-I (P < .05), reduced testicular size and weight (P < .001), and intense histopathological testicular abnormalities, including reduced tubular diameters (P < .001), loss of the germinal line (P < .001), and diminutions in cellular proliferation, spermatogenesis (P < .001), and testicular transferrin expression (P < .001). In addition, low serum testosterone (P < .01) and high serum LH (P < .01) were present in untreated cirrhotic animals. Cirrhotic rats that received IGF-I showed full recovery of testicular size and weight and of all histopathological abnormalities (P < .001 to < .01 vs. nontreated cirrhotic rats; P = ns vs. controls). Serum levels of sex hormones tended to normalize. In conclusion, IGF-I deficiency may play a pathogenetic role in hypogonadism of cirrhosis. Low doses of IGF-I for a short period of time revert testicular atrophy and appear to improve hypogonadism in advanced experimental cirrhosis.
p73 Is up-regulated in a subset of hepatocellular carcinomas
Authors: Herath Nirmitha I. , Kew Michael C. , Whitehall Vicki L. , Walsh Michael D. , Jass Jeremy R. , Khanna Kum Kum , Young Joanne , Powell Lawrie W. , Leggett Barbara A. , Macdonald Graeme A.
Published: July 2004

Loss of heterozygosity (LOH) at 1p36 occurs in a number of solid tumors including hepatocellular carcinoma (HCC). Recently, a novel gene, p73, has been identified at 1p36.33. p73 is structurally and functionally related to p53 located at 17p13.1, which is a target for inactivation in HCCs. p73 produces at least two splicing variants, p73α and β, and a polymorphism in exon 2 results in two alleles, GC or AT. Initially, only the AT allele and p73α transcripts were identified in malignant cell lines, suggesting a role for these in the malignant phenotype. The aims of this study were to determine the extent of LOH at 1p36 and 17p13.1 in HCCs from Australia and South Africa, and to identify patterns of p73 mRNA and p73 and p53 protein expression. LOH at 1p36 was found in 8 of 25 Australian and 6 of 10 South African cases. p73 mRNA expression occurred in 8 HCCs, but not in nonmalignant liver tissue. Two of these 8 HCCs had LOH of 1p36. Both α and β transcripts were observed in GC/GC homozygotes and GC/AT heterozygotes. No p73 protein expression was observed by immunohistochemistry in nonmalignant liver tissue or in HCC. p53 inactivation appeared to be associated with up-regulation of p73 expression, suggesting a compensatory role for p73 in this situation. The LOH at 1p36 implies a liver-specific tumor suppressor gene is in this region. However, the up-regulation of p73 mRNA suggests p73 is not the target of this loss.
Selective blockade of mGlu5 metabotropic glutamate receptors protects rat hepatocytes against hypoxic damage
Authors: Storto Marianna , de Grazia Ugo , Knöpfel Thomas , Canonico Pier Luigi , Copani Agata , Richelmi Plinio , Nicoletti Ferdinando , Vairetti Mariapia
Published: July 2004

Western blot analysis of protein extracts from rat liver revealed the presence of the mGlu5 receptor, one of the G-protein-coupled receptors activated by glutamate (named “metabotropic glutamate receptors” or mGlu receptors). mGlu5 expression was particularly high in extracts from isolated hepatocytes, where levels were comparable with those seen in the rat cerebral cortex. The presence of mGlu5 receptors in hepatocytes was confirmed by reverse-transcription polymerase chain reaction (RT-PCR) analysis, immunohistochemistry in neonate or adult rat liver, as well as by immunocytochemical analysis in HepG2 hepatoma cells, where the receptor appeared to be preferentially distributed in cell membranes. Interestingly, mGlu1 receptors (which are structurally and functionally homologous to mGlu5 receptors) were never found in rat liver or hepatocytes. In hepatocytes exposed to anoxic conditions for 90 minutes, glutamate, (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) and quisqualate, which all activate mGlu5 receptors, accelerated the onset and increased the extent of cell damage, while 4-carboxy-3-hydroxyphenylglycine (4C3HPG), an agonist of mGlu2/3 receptors, was inactive. 2-Methyl-6-(2-phenyl-1-ethynyl)-pyridine (MPEP), a novel, noncompetitive, highly selective mGlu5 receptor antagonist, not only abolished the toxic effect of 1S,3R-ACPD, but, unexpectedly, was protective by itself against anoxic damage. This suggests that hepatocytes express mGlu5 receptors and that activation of these receptors by endogenous glutamate facilitates the development of anoxic damage in hepatocytes.
Fas- and tumor necrosis factor receptor 1-dependent but not perforin-dependent pathways cause injury in livers infected with an adenovirus construct in mice
Authors: Liu Zhang-Xu , Govindarajan Sugantha , Okamoto Shigefumi , Dennert Gunther
Published: July 2004

Intravenous injection of type 5 adenovirus, deleted in the E1 and E3 regions, is shown to result in expression of viral antigens in the liver, initiating lymphocyte infiltration and liver injury. Following this infection, induction of Fas ligand (FasL), tumor necrosis factor α (TNF-α), and perforin mRNA are all demonstrable in the liver, pointing to a role of respective pathways in liver injury. Making use of mice in which the genes coding for Fas, FasL, TNF receptors (TNFRs), and perforin are inactivated, as well as recombinant proteins that inhibit Fas- and TNF-α-mediated apoptosis, it is shown that a functional perforin-mediated mechanism is not obligatory for cellular infiltration and progression of liver injury. In contrast functional Fas- and TNF-α-mediated mechanisms were found to be essential for liver injury to occur. Results are presented demonstrating that signaling through TNFR1, but not TNFR2, is involved in TNF-α-mediated liver damage. The conclusion is drawn that although perforin mRNA is induced in the virus-infected liver, Fas- and TNF-α-mediated mechanisms constitute the principal pathways by which the cell-mediated immune system causes acute liver injury.
Opening of the mitochondrial permeability transition pore causes matrix expansion and outer membrane rupture in fas-mediated hepatic apoptosis in mice
Authors: Feldmann Gérard , Haouzi Delphine , Moreau Alain , Durand-Schneider Anne-Marie , Bringuier Annie , Berson Alain , Mansouri Abdellah , Fau Daniel , Pessayre Dominique
Published: July 2004

Although Fas stimulation has been reported to cause outer mitochondrial membrane rupture in Jurkat cells, the mechanism of this effect is debated, and it is not known if outer membrane rupture also occurs in hepatocyte mitochondria. We studied the in vivo effects of Fas stimulation on ultrastructural lesions and mitochondrial function in mice. Four hours after administration of an agonistic anti-Fas antibody (8 μg/animal), caspase activity increased 5.4-fold. Nuclear DNA showed internucleosomal fragmentation, whereas supercoiled mitochondrial DNA was replaced by circular and linear forms. Mitochondrial cytochrome c was partly released into the cytosol. Ultrastructurally, mitochondrial lesions were observed in both apoptotic hepatocytes (with nuclear chromatin condensation/fragmentation) and nonapoptotic hepatocytes (without nuclear changes). In nonapoptotic cells, outer mitochondrial membrane rupture allowed herniation of the inner membrane and matrix through the outer membrane gap. In apoptotic hepatocytes, the matrix became electron-lucent and no longer protruded through the outer membrane gap. Mitochondria clustered around the nucleus, whereas rough endoplasmic reticulum cisternae became peripheral. In liver mitochondria isolated after Fas stimulation, the membrane potential decreased, whereas basal respiration increased. Pretreatment with either z-VAD-fmk (an inhibitor of caspases) or cyclosporin A (a permeability transition inhibitor) totally or mostly prevented mitochondrial outer membrane rupture, membrane potential decrease, cytochrome c release, and apoptosis. In conclusion, in vivo Fas stimulation causes caspase activation, mitochondrial permeability transition (decreasing the membrane potential and increasing basal respiration), mitochondrial matrix expansion (as shown by matrix herniation), outer mitochondrial membrane rupture, and cytochrome c release.
Contribution of reduced insulin sensitivity and secretion to the pathogenesis of hepatogenous diabetes: Effect of liver transplantation
Authors: Perseghin Gianluca , Mazzaferro Vincenzo , Sereni Lucia Piceni , Regalia Enrico , Benedini Stefano , Bazzigaluppi Elena , Pulvirenti Andrea , Leão Adriana Antonio Silva , Calori Giliola , Romito Raffaele , Baratti Dario , Luzi Livio
Published: July 2004

Diabetes mellitus frequently complicates cirrhosis but the pathogenic mechanisms are unknown. To assess the contribution of reduced insulin action and secretion, 24 cirrhotic-diabetic patients waiting for liver transplant because of an unresectable hepatocarcinoma underwent an oral glucose tolerance test (OGTT) to assess the β-cell function and an insulin clamp combined with [3-3H]glucose infusion to measure whole body glucose metabolism before and 2 years after the transplant. Seven cirrhotic nondiabetic patients, 11 patients with chronic uveitis on similar immunosuppressive therapy, and 7 healthy subjects served as control groups. Cirrhotic patients showed a profound insulin resistance, and diabetics in addition also showed increased endogenous glucose production (P < .05) and insulin deficiency during the OGTT (P < .05). Liver transplantation normalized endogenous glucose production and insulin sensitivity but failed to cure diabetes in 8 of the 24 patients because a markedly low insulin response during the OGTT. Age, body mass index, family history of diabetes, immunosuppressive drugs, and pathogenesis of cirrhosis did not predict in whom liver transplant was going to cure diabetes. On the contrary, a reduced secretory response characterized the patients in whom the transplant would not be curative. In summary, insulin resistance was a primary event complicating cirrhosis but additional β-cell secretory defects were crucial for development of diabetes. Liver transplantation, lessening insulin resistance, cured hepatogenous diabetes in 67% of cirrhotic-diabetic patients; nevertheless 33% were still diabetics because the persistence of a reduced β-cell function, which makes these patients eventually eligible for combined islet transplantation.
Novel molecular defects of the δ-aminolevulinate dehydratase gene in a patient with inherited acute hepatic porphyria
Authors: Akagi Reiko , Shimizu Ryo , Furuyama Kazumichi , Doss Manfred O. , Sassa Shigeru
Published: July 2004

Cloning and expression of the defective gene for δ-aminolevulinate dehydratase (ALAD) from the second of 2 German patients with ALAD deficiency porphyria (ADP), who had been originally reported by Doss et al. in 1979, were performed. Cloning of cDNAs for the defective ALAD were performed using Epstein-Barr virus (EBV)-transformed lymphoblastoid cells of the proband, and nucleotide sequences of cloned cDNA were determined. Two separate mutations of ALAD cDNA were identified in each ALAD allele. One was G457A, termed “H1,” resulting in V153M substitution, while the other was a deletion of 2 sequential bases at T818 and C819, termed “H2,” resulting in a frame shift with a premature stop codon at the amino acid position of 294. Using allele-specific oligonucleotide hybridization, the mother of the proband was shown to have an H1 defect, while using genomic DNA analysis, the father was shown to have an H2 defect. Expression of H1 cDNA in Chinese hamster ovary cells produced an ALAD protein with only a partial activity (10.65% ± 1.80% of the normal), while H2 cDNA encoded no significant protein. These data thus demonstrate that the proband was associated with 2 novel molecular defects of the ALAD gene, 1 in each allele, and account for the extremely low ALAD activity in his erythrocytes.
Activation of N -methyl-d-aspartate receptors in rat brain in vivo following acute ammonia intoxication: Characterization by in vivo brain microdialysis
Authors: Hermenegildo Carlos , Monfort Pilar , Felipo Vicente
Published: July 2004

Ammonia is considered the main agent responsible for the neurological alterations in hepatic encephalopathy. It was suggested that ammonia toxicity is mediated by activation of N-methyl-d-aspartate (NMDA) receptors. The aim of this work was to assess, by in vivo brain microdialysis in freely moving rats, whether acute ammonia intoxication leads to activation of NMDA receptors in the cerebellum of the rat in vivo. We measured the effects of ammonia intoxication on the neuronal glutamate-nitric oxide-cyclic guanosine monophosphate (cGMP) pathway, by measuring the ammonia-induced increase of extracellular cGMP. Ammonia intoxication increases extracellular cGMP, and this increase is prevented by (5R,10S)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine hydrogen maleate (MK-801). There is a good correlation between the increase in cGMP and the seriousness of the neurological symptoms elicited by different doses of ammonia. Ammonia doses inducing coma did not affect extracellular glutamate, while doses leading to death increased it by 349%. The time courses of ammonia-induced increases in extracellular ammonia, cGMP, and glutamate indicate that NMDA receptor activation occurs before the increase in extracellular glutamate. Ammonia-induced increase in glutamate is prevented by MK-801. These results indicate that ammonia intoxication leads to activation of NMDA receptors in the animal in vivo, and that this activation is not caused by increased extracellular glutamate. The possible underlying mechanism is discussed.