bluuebunny/crossref_metadata_2025 huggingface dataset:
Lamivudine Is Effective in Suppressing Hepatitis B Virus Dna in Chinese Hepatitis B Surface Antigen Carriers: A Placebo–Controlled Trial
Authors: Lai C. , Ching C. , Tung A. K. , Li E. , Young J. , Hill A. , Wong B. C. , Dent J. , Wu P.
Published: July 2004

Lamivudine is a novel 2′,3′–dideoxy cytosine analogue that has potent inhibitory effects on hepatitis B virus replication

in vitro

and

in vivo

. We performed a single–blind, placebo–controlled study to assess its effectiveness and safety in Chinese hepatitis B surface antigen (HBsAg) carriers. Forty–two Chinese HBsAg carriers were randomized to receive placebo (6 patients) or lamivudine orally in dosages of 25 mg, 100 mg, or 300 mg daily (12 patients for each dosage). The drug was given for 4 weeks. The patients were closely monitored clinically, biochemically, and serologically up to 4 weeks after drug treatment. All 36 patients receiving lamivudine had a decrease in hepatitis B virus (HBV) DNA values of >90% (

P

< .001 compared with placebo). Although 25 mg of lamivudine was slightly less effective than 100 mg (

P

= .011) and 300 mg (

P

= .005), it still induced 94% suppression of HBV DNA after the fourth week of therapy. HBV DNA values returned to pretreatment levels within 4 weeks of cessation of therapy. There was no change in the hepatitis B e antigen status or in aminotransferase levels. No serious adverse events were observed. In conclusion, a 4–week course of lamivudine was safe and effective in suppression of HBV DNA in Chinese HBsAg carriers. The suppression was >90% but reversible. Studies with long–term lamivudine administration should be performed to determine if prolonged suppression of HBV DNA can be achieved.
Cystic Fibrosis Transmembrane Conductance Regulator Mediates the Cyclic Adenosine Monophosphate–Induced Fluid Secretion But Not the Inhibition of Resorption in Mouse Gallbladder Epithelium
Authors: Peters R H , van Doorninck J H , French P J , Ratcliff R , Evans M J , Colledge W H , Bijman J , Scholte B J
Published: July 2004

ABSTRACT

We have studied the physiological role of the cystic fibrosis (CF) gene product (cystic fibrosis transmembrane conductance regulator [CFTR]) in gallbladder epithelium using a knockout mouse model for CF. We found that normal mouse gallbladder epithelium expresses functional CFTR as shown by reverse–transcription polymerase chain reaction (RT–PCR) analysis and Ussing chamber experiments. Gallbladders from

Cftr

-/- mice were structurally intact as shown by microscopic and physiological parameters but lacked the cyclic adenosine monophosphate (cAMP)–induced chloride current observed in normal gallbladders. In fluid transport measurements, normal and

Cftr

-/- gallbladders were equally active in basal resorption. The addition of forskolin, which activates CFTR anion channel activity through the cAMP system, resulted in net fluid secretion in normal gallbladders. In contrast,

Cftr

-/- gallbladders were unable to secrete fluid while a complete inhibition of resorption by forskolin was observed. We conclude that, in normal mouse gallbladder epithelium, cAMP–induced fluid secretion involves simultaneous inhibition of apical sodium chloride resorption and activation of CFTR. Our data support the hypothesis that gallbladder disease in CF is at least in part caused by a deficient secretory response to the endogenous cAMP–linked hormones VIP and secretin.
Benzoic Acid Metabolism Reflects Hepatic Mitochondrial Function in Rats With Long–Term Extrahepatic Cholestasis
Authors: Krähenbühl L , Reichen J , Talos C , Krähenbühl S
Published: July 2004

ABSTRACT

Benzoic acid metabolism, which is primarily a function of liver mitochondria, depending on the concentration of adenosine triphosphate (ATP), coenzyme A (CoA), and glycine in the mitochondrial matrix, was investigated in both rats with long–term cholestasis caused by bile duct ligation (BDL) and sham–operated control rats. In isolated liver mitochondria, hippurate production from benzoate in the presence of saturating glycine concentrations was reduced in BDL rats by 36% with l–glutamate as a source for ATP, by 21% in the presence of succinate, and by 31% in the presence of ATP plus oligomycine. This reduction in benzoate metabolism is in the same range as the previously observed reduction in the activity of the electron transport chain in liver mitochondria from BDL rats. The mitochondrial CoA pool, which can be rate–limiting for benzoic acid metabolism, was not different between BDL and control rats. The activity of benzoyl–CoA synthase, the enzyme catalyzing the rate–limiting step in benzoate metabolism, was reduced by 25%, and the activity of benzoyl–CoA:glycine

N

–transferase was reduced by 66% in BDL rats. The activity of benzoyl–CoA synthase was significantly inhibited by lithocholate, suggesting that hepatic accumulation of hydrophobic bile acids could contribute to the observed reduction of benzoate metabolism in BDL rats. Benzoate metabolism was also studied

in vivo

by monitoring the urinary hippurate excretion after intraperitoneal administration of benzoate (100 μmol/100 g of body weight). The time course of hippurate excretion was not different between BDL and control rats. Hippurate excretion over 24 hours after benzoate administration averaged 89.7 ± 4.0% of the administered dose in BDL and 74.4 ± 6.9% (mean ± SEM, difference not significant) in control rats. This finding could be explained by an increase in mitochondrial protein in BDL rats, averaging 2.34 ± 0.29 g per liver in BDL and 1.35 ± 0.07 g per liver in control rats (mean ± SEM,

p

< .05). Thus, the studies show that benzoate metabolism reflects mitochondrial function in BDL rats both

in vivo

and

in vitro

, and that mitochondrial proliferation compensates for the observed decrease in benzoic acid metabolism in isolated mitochondria

in vitro

.
Neural Networks As Predictors of Outcomes in Alcoholic Patients With Severe Liver Disease
Authors: Lapuerta P , Rajan S , Bonacini M
Published: July 2004

ABSTRACT

We developed and evaluated neural networks as predictors of outcomes in alcoholic patients with severe liver disease using commonly available clinical and laboratory values. Hospital charts of 144 patients were reviewed. Nine variables (five laboratory, four clinical) were recorded along with in–hospital death or survival. Data were organized into separate development and validation sets. Neural network predictions of survival were compared with those of the Maddrey discriminant function and logistic regression models developed on the same data. Model performance was evaluated by comparing areas under receiver–operating characteristic (ROC) curves and the distributions of model scores. Survivors had significantly different laboratory and clinical characteristics, the most important being a higher prothrombin time, lower bilirubin, and lower incidence of encephalopathy. Neural network performance was significantly better than that of the Maddrey score (ROC areas, 81.5% vs. 73.8%;

P

= .04). The ROC area for neural networks was similar to that of logistic regression (ROC area 78.2%;

P

= .3), but the neural networks were more successful in classifying patients into low– and high–risk groups (

P

< .001). A neural network score with laboratory data from hospital–day 7 improved prognostic accuracy further to 84.3%. After adjusting for baseline risk, the neural network change in illness severity was still a significant predictor of mortality (

P

= .001). Neural networks using clinical and laboratory data showed a high prognostic accuracy for predicting mortality in alcoholic patients with severe liver disease.
Risk Factors for Hemorrhage From Gastric Fundal Varices
Authors: Kim T , Shijo H , Kokawa H , Tokumitsu H , Kubara K , Ota K , Akiyoshi N , Iida T , Yokoyama M , Okumura M
Published: July 2004

ABSTRACT

The incidence and the risk factors of hemorrhage from gastric fundal varices (FV) have not been fully evaluated. We therefore conducted a retrospective and prospective study to define the incidence and risk factors for such episodes. We investigated 132 patients with cirrhosis and gastric FV. Of these 132 patients, 15 patients had hemorrhagic FV at the time of enrollment. The clinical characteristics were compared between these patients and those without a first hemorrhage from FV. In the patients who had never previously bled, the incidence and risk factors were prospectively investigated. The size of FV was greater and red–spot on the FV were more prevalent in patients with hemorrhagic FV. Child's status was also more severe in these patients. In the 117 patients who had never bled, 34 hemorrhages from FV occurred during the follow–up period. The cumulative risk for such hemorrhage at 1, 3, and 5 years was 16%, 36%, and 44%, respectively. A multiple regression analysis (Cox's model) revealed the size of varices, red–spot on the FV, and Child's status to be statistically significant, as well as independent predictors for hemorrhage from FV. The endoscopic criteria (size of the largest varix and presence of red–spot), as well as the hepatic functional reserve, provide the most essential information for predicting a hemorrhage from FV. An estimation of the probability for hemorrhage from FV based on Cox's model may therefore be beneficial in the clinical management of patients with high–risk FV.
Lack of Renal Effects of Fish Oil Administration in Patients With Advanced Cirrhosis and Impaired Glomerular Filtration
Authors: Badalamenti S , Salerno F , Salmeron J M , Lorenzano E , Rimola A , Ginès P , Jimenez W , Graziani G , Arroyo V , Rodes J , Ponticelli C
Published: July 2004

ABSTRACT

The treatment of renal failure in cirrhotic patients with ascites remains unsatisfactory. Recent studies have shown that the dietary supplementation with fish oil improves the renal function of normal subjects, as well as that of patients with renal failure of different etiologies. We have investigated the renal effects of a daily supplementation for 1 month of 12 g fish oil (27% C20:5 n–3 eicosapentanoic acid [EPA], and 23% C22:6 n–3 docosahexanoic acid [DHA]) in a prospective study of cirrhotic patients with ascites, nine with normal renal function (group 1) and eight with renal failure (glomerular filtration rate [GFR] < 60 mL/min, group 2). Compliance with the dietary regimen was confirmed by fatty acid chromatography that showed increased plasma concentration of EPA (from 1.5 ± 0.7% to 3.7 ± 0.8%,

P

= .024, in group 1; and from 0.53 ± 0.3% to 2.9 ± 0.8%,

P

= .03, in group 2) and of DHA (from 2.1 ± 0.4% to 3.4 ± 0.3%,

P

= .008, in group 1; and from 1.45 ± 0.5% to 3.8 ± 0.4%,

P

= .05, in group 2). At the end of the study, in patients from group 1, the glomerular filtration rate increased by 19% (from 94 ± 8 to 113 ± 13 mL/min,

P

= .039), and the urine flow increased by 39% (from 0.85 ± 0.14 to 1.12 ± 0.2 mL/min,

P

= .039), while no changes occurred in the renal function of patients from group 2. No changes were observed in the urinary excretion of prostaglandin (PG) E2 or of 6–keto prostaglandin–1–alpha (6–K–PGF1–alpha) nor in plasma renin activity (PRA) or the plasma concentration of aldosterone (PA) or antidiuretic hormone (ADH) in both groups. As far as undesirable effects of fish oils were considered, the mean arterial pressure (MAP) decreased in both groups (group 1: from 88.6 ± 2 to 85.3 ± 2 mm Hg,

P

= .015; group 2: from 88.2 ± 3 to 82.8 ± 3 mm Hg,

P

= .05), and bleeding time displayed a significant increase when patients were considered collectively (from 744 ± 89 to 872 ± 106 seconds,

P

= .0068). In conclusion, the administration of fish oil for 1 month was unable to improve renal function in cirrhotic patients with ascites and renal failure. The occurrence of undesirable effects, such as the reduction of arterial pressure and the prolongation of bleeding time, argues against the use of fish oils in these patients.
Associations Between Alleles of the Major Histocompatibility Complex and Type 1 Autoimmune Hepatitis
Authors: Czaja A J , Strettell M D , Thomson L J , Santrach P J , Moore S B , Donaldson P T , Williams R
Published: July 2004

ABSTRACT

Susceptibility for type 1 autoimmune hepatitis has been associated with the major histocompatibility alleles DRB1*0301, DRB3*0101, DRB1*0401, and DRB4*0103, whereas the DRB1*1501 allele may protect from the disease. Our aim was to determine if these alleles or others influence clinical manifestations and prognosis. Eighty–six white patients were evaluated prospectively for immune features and outcomes. Class I alleles were determined by microlymphocytotoxicity, and class II alleles were assessed by polymerase chain reaction with sequence–specific oligonucleotide probes or sequence–specific primers. One hundred two white, normal subjects were typed in the same fashion. Patients with concurrent immunologic diseases were more commonly positive for DRB4*0103 than patients without these features (68% vs. 38%,

P

= .01). DRB1*0301 (86% vs. 45%,

P

= .008) and the DRB1*0301–DRB3*0101 haplotype (79% vs. 42%,

P

= .02) occurred more commonly in patients who deteriorated during corticosteroid therapy. In contrast, DRB1*0401 and the DRB1*0401–DRB4*0103 haplotype were associated with a lower frequency of death from liver failure or the need for transplantation than patients with other alleles (0% vs. 37%,

P

= .03). Patients with DRB1*0301 differed from those with DRB1*0401 in that they were younger and failed treatment more commonly (27% vs. 5%,

P

= .04). We conclude that alleles associated with susceptibility to type 1 autoimmune hepatitis also influence its clinical features and prognosis. DRB4*0103 is associated with concurrent immune diseases, DRB1*0301 with a poor treatment response, and DRB1*0401 with a lower frequency of hepatic death or transplantation.
Gene Expression of Glucokinase Regulatory Protein in Regenerating Rat Liver
Authors: Rosa J L , Pérez J X , Detheux M , Van Schaftingen E , Bartrons R
Published: July 2004

ABSTRACT

The activity and messenger RNA (mRNA) levels of glucokinase, and the concentration and mRNA levels of its regulatory protein, were analyzed during liver regeneration. The activity of glucokinase and the concentration of its regulatory protein decreased to 30% and 50%, respectively, after liver resection, remaining low after 1 week. No significant variations in the level of these proteins were found in sham–operated animals. The regulatory protein/glucokinase molar ratio increased during the replicative phase, to a maximum at 48 hours. The mRNA levels of glucokinase and of its regulatory protein decreased rapidly after partial hepatectomy to minimum values at 6 hours (15%) and at 12 hours (4%), respectively, returning to normal values at 24 hours and 168 hours, respectively. Sham–operated animals showed a similar decrease in mRNA levels during the prereplicative phase of liver regeneration, suggesting that the initial effects observed in the gene expression of these proteins were due to surgical stress. During the replicative phase, a specific inhibition of the regulatory protein's gene expression was observed in the regenerating liver. A decrease in the content of regulatory protein and the glucokinase activity, and an increase in the molar ratio of these two proteins correlate with the observed decrease in glycolytic flux, providing further evidence that the phosphorylation of glucose is a control point in the glycolytic/gluconeogenic flux during liver regeneration.
Isolation of Oval Cells From Long–Evans Cinnamon Rats and Their Transformation Into Hepatocytes In Vivo In the Rat Liver
Authors: Yasui O , Miura N , Terada K , Kawarada Y , Koyama K , Sugiyama T
Published: July 2004

ABSTRACT

Oval cells function as compensatory cells in severe liver injury and are thought to be equivalent to liver stem/progenitor cells. We isolated oval cells from the liver of Long–Evans Cinnamon (LEC) rats by isopyknic centrifugation in a Percoll gradient. The cells were gamma–glutamyl transpeptidase (GGTP)–positive, alpha–fetoprotein–positive, and cytokeratin (CK) 18– and CK 19–positive, but albumin–negative in the cells. When oval cells were transplanted to the liver, they were transformed into hepatocytes. To evaluate albumin biosynthesis, we transplanted oval cells into the liver of Nagase analbuminemic and LEC double mutant rats. The albumin level in the serum of transplanted rats was increased and maintained for up to 10 weeks. These results indicated that the oval cells isolated from LEC rats can differentiate into hepatocytes

in vivo

.
Chronic Alcohol Intoxication Induces Hepatic Injury Through Enhanced Macrophage Inflammatory Protein–2 Production and Intercellular Adhesion Molecule–1 Expression in the Liver
Authors: Bautista A P
Published: July 2004

ABSTRACT

This study tested the hypothesis that prolonged consumption of alcohol directly or indirectly, through endotoxin influx in the circulation, stimulates the Kupffer cells to produce macrophage inflammatory protein–2 (MIP2) and up–regulates the expression of adhesion molecules, i.e., CD18 on PMNs and its counter–receptor, intercellular adhesion molecule–1 (ICAM–1), on hepatic cells. As a result, enhanced sequestration and cell–cell interaction among these cell types may occur in the liver, which in turn could result in altered hepatic function and hepatotoxicity. This hypothesis was tested in alcohol–fed, specific pathogen–free, male Sprague–Dawley rats. After 16 weeks of feeding, endotoxin (0.2 ± 0.043 EU/mL) and MIP2 (625 ± 100 pg/mL) were detected in the sera of alcoholic rats but not in the pair–fed rats. Concomitantly, serum aspartate transaminase (AST) activity was significantly increased. Small lipid deposition and inflammatory–like changes in the liver were also observed. Isolated Kupffer cells from alcohol–fed rats released large amount of MIP2 (> 600 pg/106 Kupffer cells/24 hr)

in vitro

compared with Kupffer cells from pair–fed rats (< 150 pg/106 Kupffer cells/24 hr). At the same time, the expression of CD18 and ICAM–1 on polymorphonuclear neutrophils (PMNs) and hepatic cells was increased more than twofold. Monoclonal antibody 1F12, an anti–CD18 antibody, attenuated hepatic injury in vivo, and in PMN–hepatocyte coculture

in vitro

in the alcohol–fed group. Another factor that could contribute to hepatic injury was MIP2, which was cytotoxic to alcoholic hepatocytes

in vitro

. This was reversed by cycloheximide, thus suggesting the indirect hepatotoxic effect of MIP2. In addition, isolated PMNs and Kupffer cells from alcohol–fed rats released large amounts of superoxide, which may also play a role in hepatic injury. These results demonstrate that MIP2 and adhesion molecules may contribute, at least in part, in the initiation of hepatic injury during alcohol intoxication.
Effect of Chronic Ethanol Feeding on Lipid Peroxidation and Protein Oxidation in Relation to Liver Pathology
Authors: Rouach H , Fataccioli V , Gentil M , French S W , Morimoto M , Nordmann R
Published: July 2004

ABSTRACT

Liver lipid peroxidation, nonheme iron, antioxidants, and protein oxidation were investigated in experimental alcohol–induced liver disease in the rat. Wistar male rats were intragastrically and continuously infused for 4 weeks with a high–fat diet plus an ethanol or an isocaloric amount of dextrose, maintaining a high blood alcohol level (200–300 mg%). This model induced fatty liver, spotty necrosis, and focal inflammation. This pathology was associated with an enhanced lipid peroxidation and a decrease in the major antioxidant factors. Hepatic alpha–tocopherol and glutathione concentrations were significantly decreased in ethanol–fed rats. Glutathione peroxidase (GPx) was also decreased, whereas glutathione S–transferase (GST) was unaffected. The nonheme iron level was significantly decreased. Protein oxidation was assessed through three parameters: protein thiols, protein carbonyl groups, and the activity of glutamine synthetase (GS), a centrilobular enzyme particularly susceptible to free–radical– mediated damage. Ethanol–fed rats had decreased protein thiol concentrations and reduced GS activity, together with increased protein carbonyls. A significant correlation between GS activity and the pathological score was observed. This study confirms the ethanol–related increase in lipid peroxidation and shows that ethanol impairs the hepatic antioxidant potential. Furthermore, evidence of oxidative protein damage is given, including decreased activity of a key enzyme of ammonia metabolism. These protein disturbances may contribute to the pathogenesis of the observed liver damage.
Neutrophil–Derived Superoxide Anion Induces Lipid Peroxidation and Stimulates Collagen Synthesis in Human Hepatic Stellate Cells: Role of Nitric Oxide
Authors: Casini A , Ceni E , Salzano R , Biondi P , Parola M , Galli A , Foschi M , Caligiuri A , Pinzani M , Surrenti C
Published: July 2004

ABSTRACT

Experimental evidence indicates that the lipid peroxidation of biological membranes is often associated with the development of liver fibrosis. We have studied the effect of neutrophil–derived reactive oxygen species (ROS) on collagen synthesis by human hepatic stellate cells (HSC), the major source of collagen in the liver, in a coculture system. Lipid peroxidation in the cocultures was evaluated in terms of either malondialdehyde (MDA) production or the formation of MDA/4–hydroxynonenal protein adducts. The expression of cellular messenger RNAs (mRNAs) was evaluated by either Northern blotting or RNAse protection assay. Nitric oxide (NO) synthase activity in cells was measured by [3H]citrulline formation from [3H]arginine.

In vitro

exposure of HSC to ROS resulted in the early induction of lipid peroxidation and was associated with a marked increase (threefold) of procollagen I mRNA expression and synthesis. The addition of antioxidants, such as vitamin E or superoxide dismutase (SOD), impaired this stimulation. The inhibition of neutrophil NO formation by NG–monomethyl–l–arginine made the ROS–induced stimulation of procollagen I more evident. The addition of xanthine/xanthine oxidase X/XO, a superoxide anion donor, to HSC cultures strongly increased procollagen I synthesis. This stimulation was hampered by the addition of both SOD and sodium nitroprusside (an NO donor). The contribution of HSC to the production of NO in our coculture system was negligible, because inducible NO synthase (iNOS) mRNA was almost undetectable in these cells, and also because the amount of NO produced by HSC stimulated with tumor necrosis factor α (TNF–α) and lipopolysaccharide (LPS) was 500 times less than that synthesized by neutrophils. In conclusion, these results indicate that neutrophil–derived ROS may contribute to the development of hepatic fibrosis associated with alcoholic hepatitis. NO produced by neutrophils may exert a “protective” antioxidant effect by operating as a scavenger of superoxide anion.
Altered Hepatocellular Ca2+ Regulation During Hemorrhagic Shock and Resuscitation
Authors: Rose S , Pizanis A , Silomon M
Published: July 2004

ABSTRACT

The present study evaluated the effect of the benzothiazepine Ca2+ channel blocker diltiazem (DZ) on altered hepatocellular Ca2+ regulation and oxidant injury during hemorrhagic shock/resuscitation. In anesthetized, male Sprague–Dawley rats, hemorrhagic shock was induced by rapid blood withdrawal and maintaining the mean arterial blood pressure at 40 mm Hg over 60 minutes. Rats were then resuscitated with 60% of shed blood and threefold the shed blood volume of Ringer's lactate. At the end of ischemia, and 60 or 300 minutes after resuscitation, hepatocytes were isolated by liver collagenase perfusion. Hepatocellular Ca2+ exchange (Ca2+
ex), rate of cellular Ca2+ influx (Ca2+
in), and Ca2+ membrane flux (Ca2+
flux) were determined using 45Ca incubation techniques. Hepatocyte oxidant injury was evaluated by fluorometrically measuring thiobarbituric acid reactive substances and oxidized/reduced glutathione. Both hemorrhage and hemorrhage/resuscitation increased hepatocellular Ca2+
in, Ca2+
ex, and Ca2+
flux. In contrast to control and sham–operated rats, in vitro stimulation by the Ca2+ agonist epinephrine (100 nmol/L) of hepatocytes from either hemorrhaged or resuscitated rats did not further increase Ca2+
in. Administration of DZ (.8 mg/kg) with resuscitation significantly decreased cellular Ca2+
ex and Ca2+
flux, but did not restore impaired epinephrine–induced Ca2+
in. DZ prevented hepatocyte lipid peroxidation and glutathione oxidation. These findings suggest hepatocellular Ca2+ overload and impaired Ca2+ signaling during hemorrhage/resuscitation. Increased Ca2+ uptake could be because of a receptor–gated Ca2+ influx and/or oxygen–free radical induced membrane Ca2+ leaks.
Regulation of Rat Liver S –Adenosylmethionine Synthetase During Septic Shock: Role of Nitric Oxide
Authors: Avila M A , Mingorance J , Martínez-Chantar M L , Casado M , Martín-Sanz P , Boscá L , Mato J M
Published: July 2004

ABSTRACT

We investigated the modulation of rat liver S–adenosylmethionine (SAM) synthetase in a model of acute sepsis. Our results show that animals treated with bacterial lipopolysaccharide experience a marked decrease in liver SAM synthetase activity. No changes were detected in the hepatic levels of SAM synthetase protein, suggesting that inactivation of the existing enzyme was the cause of the observed activity loss. Lipopolysaccharide treatment resulted in the expression of calcium–independent/cytokine–inducible nitric oxide (NO) synthase in liver and the accumulation in plasma of the NO–derived species nitrite and nitrate. NO implication in the

in vivo

regulation of SAM synthetase was evaluated in animals treated with the NO donor molecule 3–morpholinosydnonimine. The analysis of liver enzymatic activity, along with protein and messenger RNA levels yielded results similar to those obtained with lipopolysaccharide treatment. To assess directly the sensitivity of SAM synthetase to NO, the rat liver–purified high– and low–molecular weight forms of the enzyme were exposed to various doses of 3–morpholinosydnonimine and other NO donors such as

S

–nitroso–

N

–acetylpenicillamine, resulting in a dose–dependent inhibition of enzymatic activity. This effect was reversed by addition of the reducing agents beta–mercaptoethanol and glutathione. Finally, cysteine 121 was identified as the site of molecular interaction between NO and rat liver SAM synthetase that is responsible for the inhibition of the enzyme. To reach this conclusion, the 10 cysteine residues of the enzyme were changed to serine by site–directed mutagenesis, and the effect of NO on the various recombinant enzymes was measured.
Relative Impact of Hla Phenotype and Cd4–Cd8 Ratios on the Clinical Expression of Hemochromatosis
Authors: Porto G , Vicente C , Teixeira M A , Martins O , Cabeda J M , Lacerda R , Gonçalves C , Fraga J , Macedo G , Silva B M , Alves H , Justiça B , de Sousa M
Published: July 2004

ABSTRACT

Hemochromatosis is a hereditary iron–overload disease linked to HLA. The clinical expression of hemochromatosis is influenced by sex and age. However, other factors must account for the notorious heterogeneity of expression of the disease independent of sex, age, and HLA phenotype. The present study attempts to clarify some of these additional factors based on exhaustive statistical analysis of data collected from 43 selected patients with hemochromatosis. The statistical analysis focused on three groups of variables: the first group included variables reflecting the clinical expression of the disease; the second group represented the biochemical and hematological values at the time of diagnosis; and the third group consisted of the independent variables sex, age, HLA phenotype, and T–cell subset profile, i.e., the percentages and total numbers of CD4+ and CD8+ cells and the CD4–CD8 ratios. The results show that the relative expansion of the two main T–cell subsets, in the context of the HLA phenotype, correlates significantly with the clinical expression of hemochromatosis and the severity of iron overload. The present findings substantiate further the postulate that T cells have a role in the regulation of iron metabolism.
The In Vivo Effect of Hepatotrophic Factors Augmenter of Liver Regeneration, Hepatocyte Growth Factor, and Insulin–Like Growth Factor–Ii on Liver Natural Killer Cell Functions
Authors: Francavilla A , Vujanovic N L , Polimeno L , Azzarone A , Iacobellis A , Deleo A , Hagiya M , Whiteside T L , Starzl T E
Published: July 2004

ABSTRACT

Fine balanced sequential changes of the levels of circulating hepatotrophic factors are essential for normal liver regeneration. Our recent studies have indicated that liver–resident natural killer (NK) cells are important regulators of liver regeneration and have raised the possibility that hepatotrophic factors might mediate their activities through NK cells. In the present study, we assessed the effects of

in vivo

administration of three hepatotrophic factors (augmenter of liver regeneration [ALR], insulin–like growth factor–II [IGF–II], and hepatocyte growth factor [HGF]) on NK cells in normal rats. Each of the three, given over a 1–day period in doses known to produce hepatotrophic activity, induced inhibition of NK cell cytotoxic activities in the population of mononuclear leukocytes (MNL) in the liver, but not in MNL from the spleen or peripheral blood. In contrast to these results obtained by the whole animal treatment, the three molecules had no effect on NK cell functions when added to cultures of MNL from the livers, spleens, or blood of untreated rats. These data support and extend our previously advanced hypothesis that ALR and other hepatotrophic factors play an important role in liver regeneration by regional regulation of NK cells through some as–yet–unknown intermediary mechanism.
Assessment of the Longevity of the Liver Using A Rat Transplant Model
Authors: Sakai Y , Zhong R , Garcia B , Zhu L , Wall W J
Published: July 2004

ABSTRACT

To assess the longevity of the liver, arterialized, orthotopic liver grafts were performed using syngeneic male BN/BiRij rats. Young (5–month–old) livers were transplanted into 5–month–old recipients (group I, n = 27), and old (28–month–old) livers were transplanted into 5–month–old rats (group II, n = 28). Recipient survival after transplantation was similar in both groups. The average age of the livers at the time of death was 16.7 months in group I and 39.1 months in group II. Four of the livers in group II survived for more than 4 years (48.1 to 52.4 months). Early deaths (less than 1 year) after transplantation were most commonly caused by biliary obstruction and cholangitis in both groups. Late deaths (more than 1 year) after grafting were mainly from heart failure or tumors. None of the animals died of liver failure or liver disease. Weight gain in the rats, total serum protein levels, and alanine transaminase levels after transplantation did not differ significantly between the two groups. There was a trend for the histological features of aging of the liver—fibrosis, bile duct proliferation, and pigment deposition—to become more prevalent as the livers became very old (mean age, 46 months). Nevertheless, typical aging changes, as individual findings, were absent in nearly half of the oldest organs. The alterations in morphology had no apparent effect on the ability of the livers to sustain the lives of the recipients. The liver of the BN/BiRij rat was capable of surviving far beyond the maximum life span of BN/BiRij rats, and rats in general. It did not become diseased in the process.
Preoperative Determination of the Surgical Procedure for Hepatectomy Using Technetium–99M–Galactosyl Human Serum Albumin (99MTc–Gsa) Liver Scintigraphy
Authors: Kwon A , Ha-Kawa S K , Uetsuji S , Inoue T , Matsui Y , Kamiyama Y
Published: July 2004

ABSTRACT

Technetium–99m–diethylenetriaminepentaacetic acidgalactosyl human serum albumin (Tc–GSA) is a new liver scintigraphy agent which binds to the asialoglycoprotein receptors. We evaluated the preoperative assessment for hepatectomy using Tc–GSA liver scintigraphy. Ninety patients with hepatocellular carcinoma were admitted for elective hepatectomy. Tc–GSA scintigraphy was conducted after the intravenous injection of Tc–GSA, and maximal removal rate of Tc–GSA (GSA–Rmax) was calculated using a radiopharmacokinetic model. Measurement of GSA–Rmax, conventional liver function, and 15–minute retention rate of indocyanine green (ICGR15) was carried out preoperatively. The relationships between liver functions, histological activity index (HAI), ICGR15, and GSA–Rmax values were estimated. A significant correlation was obtained between GSA–Rmax and ICGR15 (

r

= .534,

P

< .0001). Preoperative discrepancies between GSA–Rmax and ICGR15 values were seen in 15 patients. In these cases, the GSA–Rmax values correlated well with the total HAI scores (

r

= .595,

P

< .02), but no significant correlation was seen between the ICGR15 and HAI scores. Two patients died of postoperative liver failure within 2 months of the operation. These two patients were found to have severe discrepancies between their preoperative GSA–Rmax and ICGR15 values. We concluded that GSA–Rmax might be useful for selecting candidates for hepatectomy and that extended hepatectomies (di– and tri–segmentectomy) are high–risk surgical procedures in the case of low GSA–Rmax scores (below 0.35).
Fulminant Hepatitis B Virus: Recurrence After Liver Transplantation in Two Patients Also Infected With Hepatitis Delta Virus
Authors: Marsman W A , Wiesner R H , Batts K P , Poterucha J J , Porayko M K , Niesters H G , Zondervan P E , Krom R A
Published: July 2004

ABSTRACT

Liver transplantation for hepatitis B virus (HBV)–related liver disease is complicated by HBV recurrence and, consequently, poor patient and graft survival. Patients transplanted for hepatitis delta virus (HDV)– related cirrhosis are reported to have a diminished incidence of HBV recurrence and improved graft survival. However, only a few reported HDV–infected patients had active HBV replicative disease before liver transplantation. In our experience, we transplanted two HDV–infected patients, both of whom had active HBV replication before liver transplantation. In one patient, hepatitis B surface antigen (HBsAg) recurred four months after transplantation. Two months later, Hepatitis Be antigen (HBeAg) and HBV–DNA became positive, and the patient died of fulminant recurrent hepatitis B and hepatitis delta. In the other patient, HBV persisted after transplantation, and 2 months later the patient required retransplantation for fulminant recurrent hepatitis B and hepatitis delta. With the second graft, the patient remained free of HBV infection for 1 year. Thereafter, the patient experienced HBV recurrence with active replication and died of fulminant hepatitis B and delta recurrence. In the first case and in the second graft of the second case, hepatitis B immunoglobulin (HBIG) immunoprophylaxis was administered in an attempt to prevent recurrence of HBV. The literature suggests that an HDV infection inhibits the replication of HBV and therefore plays a role in preventing the recurrence of HBV and improving survival. Our experience with two patients suggests that HDV infection, in the presence of active HBV replication, may not play a protective role.
Treatment of Chronic Hepatitis C With Interferon Alfa–N3: A Multicenter, Randomized, Open–Label Trial
Authors: Simon D M , Gordon S C , Kaplan M M , Koff R S , Regenstein F , Everson G , Lee Y M , Weiner F , Silverman A , Plasse T , Fedorczyk D , Liao M
Published: July 2004

ABSTRACT

We studied the antiviral effectiveness and safety of interferon alfa–n3, a natural alpha interferon which contains multiple interferon species, in the treatment of previously untreated patients with chronic hepatitis C. Seventy–seven patients were randomized to receive either 1.0, 2.5, 5.0, or 10.0 million units (MU) of interferon alfa–n3 three times a week for 24 weeks and were then followed for an additional 24 weeks. At the end of therapy, 67% of patients in the 10 MU group normalized serum alanine transaminase (ALT) levels and 59% had no hepatitis C virus (HCV) RNA detected by polymerase chain reaction. At the end of the follow–up period, 44% of patients in the 10 MU group maintained normal ALT, and 24% had nondetectable HCV RNA. Lower doses were much less effective. Interferon alfa–n3 was well tolerated and no patient developed neutralizing anti–interferon antibodies during or after the treatment period. Interferon alfa–n3 appears to be effective against hepatitis C virus and deserves further study in larger randomized controlled trials.
A Specific Antibody Response to Hcv E2 Elicited in Mice by Intramuscular Inoculation of Plasmid Dna Containing Coding Sequences for E2
Authors: Tedeschi V , Akatsuka T , Shih J W , Battegay M , Feinstone S M
Published: July 2004

ABSTRACT

As the chimpanzee, the only reliable animal model for hepatitis C virus (HCV) infection, is impractical for early stage testing of HCV vaccine candidates, we have evaluated the immune response in mice to an experimental plasmid based HCV vaccine. We used this system because DNA vaccines can be rapidly constructed without the necessity of large scale protein production and purification. In this preliminary study we tested the immune response in mice to HCV envelope glycoprotein, E2, induced by a eukaryotic expression plasmid. Protein expression was monitored by immunofluorescence in transfected tissue culture cells. Each mouse was inoculated intramuscular with 100 microg plasmid DNA and some mice were boosted after 5 weeks. Among 12 BALB/C mice inoculated, 10 developed antibody to E2 by the second week. The antibody levels increased steadily before reaching a plateau in mice receiving the booster, but in the nonboosted mice the antibody declined over time. The serum from one mouse was tested against a series of overlapping peptides covering most of E2. This serum contained antibodies recognizing two distinct epitopes beginning at amino acid 57 and amino acid 113 but no antibody was directed against peptides representing the hypervariable region of E2, antibody to which is thought to be important in HCV neutralization. We have shown that the use of plasmid based vaccines can induce a specific immune response in mice against HCV antigens. This system should be useful as the first step in vaccine development.
Demonstration of Duck Hepatitis B Virus in Bile Duct Epithelial Cells: Implications for Pathogenesis and Persistent Infection
Authors: Nicoll A J , Angus P W , Chou S T , Luscombe C A , Smallwood R A , Locarnini S A
Published: July 2004

ABSTRACT

Hepatitis B virus (HBV) has been demonstrated in bile duct epithelial cells (BDEC) during chronic infection. The persistence of virus in BDEC may play an important role in disease pathogenesis, and may be at least partly responsible for the relapse phenomenon observed in antiviral treatments using nucleoside analogues. The aims of this study were to examine the morphological changes within the liver in the duck hepatitis B model following bile duct ligation (BDL), and to assess the effect of biliary hyperplasia upon viral DNA and proteins. Seven–day–old ducklings, congenitally infected with the duck hepatitis B virus (DHBV), were subject to BDL. The pathological and virological changes were then followed at 5, 10, 15, and 20 days after ligation. All results were compared with age–matched unligated control birds congenitally infected with DHBV. To assess the early morphological changes, additional animals were sacrificed at 1, 2, 3, and 4 days post–BDL. The proportion of DHBV–infected BDEC, was examined by immunohistochemistry and

in situ

hybridization. BDL induced rapid biliary hyperplasia, with a doubling time for BDEC of 1.3 days. The proliferated BDEC displayed immunohistochemical features identical to resting BDEC. More than 50% of BDEC in unligated controls, and more than 46% of proliferated BDEC in ligated animals were positive for DHBV DNA and structural proteins. The intensity of immunohistochemical staining and

in situ

hybridization signal in the BDEC was consistently greater than that of the hepatocytes, both before and after BDL. BDL induces biliary hyperplasia in the duck model, and BDEC division does not reduce the viral burden in infected cells.
Hepatic Drug Delivery and Gene Therapy
Authors: Zern M A , Kresina T F
Published: July 2004

ABSTRACT

On September 21–22, 1995, an international meeting entitled “Targeting of Novel Therapeutics to the Liver and GI Tract” was held at the Natcher Conference Center on the campus of the National Institutes of Health. The conference was sponsored by the National Institute of Diabetes and Digestive and Kidney Diseases through the Division of Digestive Diseases and Nutrition and Digestive Diseases Interagency Coordinating Committee (DDICC). Section 440A of Public Law 94–562 in 1976 created the DDICC for the purpose of coordinating the digestive disease–related research activities of relevant federal health agencies into a coordinated program aimed at combating digestive diseases. As part of this federal effort, an assessment of the “state of the art” for targeted drug therapeutics to the liver and gene therapy was undertaken through the conference, cochaired by Dr. Mark Zern (Thomas Jefferson Medical College) and Dr. Flossie Wong–Staal (University of California, San Diego, CA). The conference was divided into four sessions: Session I was

Vectors and Techniques

; Session II was

Liver and Metabolic Diseases

; Session III was

Hepatitis and GI Disease

; and Session IV was

Approaches for HIV Infection

. This summary focuses on the new technologies and the studies directly pertaining to liver disease. Table 1 lists the techniques and their applications. Table 2 describes viral vectors that have been employed for the purpose of hepatic gene therapy. Table 3 summarizes the studies presented as posters at the conference.
Hemochromatosis and “Hla–H”: Definite!
Authors: Jazwinska E C , Powell L W
Published: July 2004

ABSTRACT

Background/Aims:

Hereditary hemochromatosis (HH), which affects some 1 in 400 and has an estimated carrier frequency of 1 in 10 individuals of Northern European descent, results in multi–organ dysfunction caused by increased iron deposition, and is treatable if detected early. Using linkage–disequilibrium and full haplotype analysis, we have identified a 250kb region more than 3 megabases telomeric of the major histocompatibility complex (MHC) that is identical–by–descent in 85% of patient chromosomes. Within this region, we have identified a gene related to the MHC class I family, termed HLA–H, containing two missense alterations. One of these is predicted to inactivate this class of proteins and was found homozygous in 83% of 178 patients. A role of this gene in hemochromatosis is supported by the frequency and nature of the major mutation and prior studies implicating MHC class I–like proteins in iron metabolism.
Gallstones and diabetes: A case-control study in a free-living population sample
Authors: De Santis A , Attili A F , Corradini S G , Scafato E , Cantagalli A , De Luca C , Pinto G , Lisi D , Capocaccia L
Published: July 2004

Data on the association between cholelithiasis and diabetes often are controversial and are mostly based on autopsies or on hospital series. Therefore, we designed a case-control study to determine the prevalence of diabetes mellitus in a group of subjects with gallstones or having undergone cholecystectomy (cases) and compared these with a control group of subjects without gallstones, selected during an epidemiological study performed on a free-living population sample. The subjects were matched for sex, age, and body mass index. We enlisted 336 cases and 336 controls, aged 30 to 69 years. All subjects with fasting glycemic levels of < 140 mg/dL and without a documented history of diabetes were submitted to a simplified oral glucose tolerance test (OGTT). All subjects who underwent OGTT were classified according to the National Diabetes Data Group (NDDG) criteria. The prevalence of diabetes in the subjects affected by gallstone disease was significantly higher than that in controls (11.6% vs. 4.8%; odds ratio [OR], 2.55; 95% confidence interval [CI], 1.39-4.67). Diabetes was more frequent in subjects with gallstone disease than in the control group, even according to sex (18.3% vs. 9.9% for men: OR, 2.03; 95% CI, 0.99- 4.2; 9.3% vs. 2.6% for women: OR, 3.85; 95% CI, 1.4-10.6). We conclude that an altered glucose metabolism may increase the risk of developing cholelithiasis in certain subjects.
Regulation of fecal bile acid excretion in male golden Syrian hamsters fed a cereal-based diet with and without added cholesterol
Authors: Turley S D , Spady D K , Dietschy J M
Published: July 2004

The objective of these studies was to investigate the comparative physiology and regulation of bile acid metabolism in the male Golden Syrian hamster by measuring the rate of fecal bile acid excretion and bile acid pool size in animals fed a cereal-based diet either alone, or with added cholesterol or cholestyramine. In group-housed hamsters fed only the plain diet fecal bile acid excretion in animals at 6, 10, and 15 weeks of age averaged 11.0, 8.0, and 6.9 μmol/d per 100 g body weight (bw), respectively. Pool size, measured by subtracting from the total amount of bile acid washed out over 12 hours of biliary diversion the amount of bile acid excreted in the stools over the same period, equalled 17.8 μmol/100 g bw in 15-week-old hamsters fed the plain diet. Hence, under basal conditions, these animals turned over about 38% of their bile acid pool daily. In hamsters fed a diet with 3% cholestyramine for 18 days, fecal bile acid excretion averaged 20.6 μmol/d per 100 g bw, and the pool size contracted to 5.8 μmol/100 g bw. In matching animals fed a diet containing 0.12% cholesterol for 30 days, hepatic cholesterol levels increased from 1.9 ± 0.1 to 12.6 ± 0.7 mg/g, fecal bile acid excretion increased marginally from 5.8 to 8.0 μmol/day per 100 g bw, while pool size was unchanged (16.6 μmol/100 g bw). When the cholesterol content of the diet was raised to 1.0%, hepatic cholesterol levels reached 66.5 ± 2.6 mg/g, but bile acid excretion remained at 8 μmol/d per 100 g bw. These data define some of the basal features of bile acid metabolism in the hamster, and substantiate the view that the marked cholesterolemic response of this species may relate partly to a limited ability to convert dietary cholesterol to bile acid.
Hepatic venous outflow block caused by short-length hepatic vein stenoses
Authors: Valla D , Hadengue A , el Younsi M , Azar N , Zeitoun G , Boudet M , Molas G , Belghiti J , Erlinger S , Hay J , Benhamou J
Published: July 2004

In contrast with the well-recognized membranous obstruction of the inferior vena cava, short-length hepatic vein stenoses are not well- recognized causes of hepatic venous outflow block. The aim of this study was to ascertain the prevalence, causes, manifestations, and outcome of short-length hepatic vein stenoses. We performed a retrospective study of patients with short-length hepatic vein stenosis among 86 patients with hepatic venous outflow block who were seen between 1970 and 1992. There were 25 patients with short-length hepatic vein stenosis. A thrombogenic condition was identified in 14 patients (56%). The lesions of the accompanying hepatic veins in these patients were variable (short-length stenoses, thromboses, or nonspecific changes) and similar to that seen in patients without short-length hepatic vein stenosis. In 3 necropsied cases, the venous lesions were suggestive of fibrous sequela of prior thromboses. In patients with short-length hepatic vein stenosis, splenomegaly (28% vs. 55%, P < .05) and hypersplenism were significantly less common; serum transaminase (P < .001) and creatinine levels (P < .02) were lower, prothrombin was higher (P < .001), and 5-year survival was significantly better (Kaplan-Meier estimates: 80% vs. 50%, P < .05). In patients with hepatic venous outflow block, short-length hepatic vein stenosis is a common lesion that appears to be the sequela of localized thrombosis. Long-term anticoagulation and percutaneous angioplasty (with or without stenting) are potentially applicable in these lesions. The long-term results of these treatments merit further evaluation.