bluuebunny/crossref_metadata_2025 huggingface dataset:
An anesthetized model of lethal canine galactosamine fulminant hepatic failure
Authors: Sielaff Timothy D. , Hu Michael Y. , Rollins Mark D. , Bloomer Joseph R. , Amiot Bruce , Hu Wei-Shou , Cerra Frank B.
Published: March 2007

A reproducible large animal model of fulminant hepatic failure was developed in the anesthetized dog by the administration of the amino sugar D-galactosamine. Galactosamine in 5% dextrose in water (D5W), was given as an intravenous bolus to 10 young male dogs weighing 27 to 30 kg. Three dogs that received an equal volume of D5W alone served as controls. Galactosamine at 0.5 g/kg (n = 5) produced significant biochemical evidence of liver injury with 100% survival at 48 hours. Galactosamine 1.0 g/kg (n = 5) yielded in 100% 48-hour mortality resulting from fulminant liver failure characterized by a progressive increase in liver enzymes, total bilirubin, ammonia, and lactate and associated coagulopathy, hypoglycemia, coma, and increased intracranial pressure. Necropsy showed liver pallor, ascites, and brain swelling. Liver histology showed significant hepatocellular necrosis. This clinically relevant large animal model will enable the quantitative evaluation of new technologies, such as the bioartificial liver, for the support of hepatic failure in humans.
Transformation of sinusoids into capillaries in a rat model of selenium-induced nodular regenerative hyperplasia: An immunolight and immunoelectron microscopic study
Authors: Dubuisson Liliane , Boussarie Liliane , Bedin Christiane-Alexine , Balabaud Charles , Bioulac-Sage Paulette
Published: March 2007

The oral administration of selenium (Se) to young rats induces, over a 2-month period, the formation of nodular regenerative hyperplasia with sinusoidal damage around nodules. Perinodular areas located in zone 1 comprise atrophic hepatocytes and capillarized sinusoids without fibrosis. We used this unique model of capillarization without fibrosis to investigate the temporal relationship between the process of capillarization and changes occurring in the deposition of components of the edxtracellular matrix. After 2 weeks of intoxication, type III collagen and fibronectin were stable, but laminin and type IV collagen had increased in zone 1, resulting in the formation of septae between portal tracts. Even at 8 weeks, these two components still formed the principal deposits in perinodular zones. Electron microscopy showed already at 1 week in zone 1 that part of the endothelial wall had detached from hepatocytes. Sinusoidal endothelial cells progressively acquired certain of the characteristics of a vascular endothelium, some proliferated, and perisinusoidal cells transformed into myofibroblasts, surrounded by deposits of laminin and type IV collagen. These results indicate that both laminin and type IV collagen are involved in capillarization without fibrosis and in angiogenesis; fibronectin would not seem to play a role.
Therapeutic serum concentrations of human alpha-1-antitrypsin after adenoviral-mediated gene transfer into mouse hepatocytes
Authors: Kay Mark A. , Graham Frank , Leland Frances , Woo Savio L. C.
Published: March 2007

Alpha-1-antitrypsin is a relatively common genetic deficiency that results in early emphysema. The liver as the natural source of most alpha-1-antitrypsin synthesis was the target organ selected for gene replacement therapy studies. Previous work used recombinant retroviral vectors that encode the human alpha-1-antitrypsin cDNA for ex vivo and direct in vivo transduction of hepatocytes in dogs and rodents. This approach led to low levels of the human protein in the serum of recipients. In this study, recombinant adenoviral vectors that express the human alpha-1-antitrypsin cDNA under the transcriptional control of the phosphoglycerate kinase (PGK) or RSV-LTR promoters have been constructed and used for the direct transduction of mouse hepatocytes in vivo. The animals transduced with the recombinant adenoviral vectors had therapeutic serum levels of human alpha-1-antitrypsin of up to 700 μg/mL. Thus, adenovirus-mediated gene transfer of the hAAT cDNA into the liver was able to produce therapeutic serum concentrations of protein.
Epithelial-mesenchymal transition in cultured neonatal hepatocytes
Authors: Pagan Roser , Llobera Miquel , Vilaró Senén
Published: March 2007

When hepatocyte-enriched fractions from neonatal rat livers were cultured for different times in the absence of added growth factors, a population of highly proliferating and migrating fibroblastlike cells appeared. Double immunofluorescence with antibodies to cytokeratin and to vimentin showed a progressive reduction in the number of cytokeratin-positive cells parallel to an increase in the vimentin-positive cells. Some cells with transitional epithelial or migrating morphology coexpressed both intermediate filament proteins. Immunofluorescence with antibodies against hepatocyte differentiation markers showed that shortly after seeding most of the cells were positive to anti-albumin antibodies, but after 1 week in culture, only 10% were positive. Cells presenting albumin and cytokeratin appeared morphologically epithelial. Fibroblastlike cells were not positive for albumin, but some cells with transitional epithelial morphology presented some labels for albumin and for vimentin. Immunofluorescence with antibodies to glutathione-S-transferase subunit Pi and vimentin showed that many fibroblastlike cells were positive for both markers, some of them binucleate. Cultures performed in the presence of dexamethasone, absence of arginine, or on collagen type I matrix had no effect on the behavior of neonatal hepatocytes. The appearance of fibroblastlike cells was ontogenically regulated because the highest increase in the percentage of vimentin-positive cells was observed in cell cultures from livers of 7-and 15-day-old animals. These data provide evidence that neonatal hepatocytes in culture have the potential to dedifferentiate by epithelial-mesenchymal transition and contribute to an understanding of hepatic growth development.
Expression of SPARC in normal and fibrotic livers
Authors: Frizell Edward , Liu Shu-Ling , Abraham Ann , Ozaki Iwata , Eghbali Mahboubeh , Sage Helene E. , Zern Mark A.
Published: March 2007

SPARC (secreted protein, acidic and rich in cysteine)—also known as osteonectin, BM-40, and 43K glycoprotein—is secreted by endothelial cells and fibroblasts in response to culture shock. SPARC has been found in association with tissues undergoing cell proliferation, migration, and extracellular matrix remodeling. We demonstrate that normal livers from humans, rats, and mice express substantial levels of SPARC messenger RNA (mRNA). Moreover, when compared with control specimens, significantly increased levels of SPARC mRNA were found in fibrotic livers from two animal models of liver disease: murine schistosomiasis and carbon tetrachloride—induced fibrosis in rats. Fibrotic human livers also had markedly increased levels of SPARC mRNA in comparison with normal livers. We also detected an increased production of SPARC protein in the liver of animals treated with carbon tetrachloride. By immunocytochemical analysis, SPARC protein was apparent in freshly isolated Ito cells. Hybridization studies showed Ito cells to be the main source of SPARC mRNA. Extracts from a Kupffer-endothelial cell fraction exhibited traces of SPARC transcript, but expression of SPARC mRNA was absent in extracts from freshly isolated hepatocytes. These studies demonstrate the increased expression of SPARC—a protein that modulates cell shape and disrupts cell-matrix interactions—during the initial stages of hepatic fibrosis.
Acute endotoxin tolerance downregulates superoxide anion release by the perfused liver and isolated hepatic nonparenchymal cells
Authors: Bautista Abraham P. , Spitzer John J.
Published: March 2007

This work is based on the hypothesis that low-dose lipopolysaccharide (LPS) suppresses the stimulatory and priming effects of a subsequent high-dose endotoxin on the formation of toxic oxygen-derived radicals by the perfused liver and isolated hepatic nonparenchymal cells. Such effects may in turn contribute to hyposensitivity to the lethal effect of large doses of endotoxin. Male Sprague-Dawley rats received a nonlethal (“lowdose”) intravenous injection of Escherichia coli LPS (0.5 mg/kg body weight) 12 to 120 hours before they were challenged by a “large dose” of endotoxin (10 mg/kg). Three hours after LPS challenge, the livers were perfused, and superoxide release was determined. Nonparenchymal cells were also isolated for the determination of superoxide anion formation in vitro. There was a low rate (0.14 ± 0.1 nmol/min/g liver weight) of superoxide generated by the perfused livers from rats that received the low-dose LPS 1 to 5 days previously. Control livers generated less than 0.08 nmol superoxide. A high rate (1.3 ± 0.1 nmol/min/g) of superoxide release was measured in the perfused liver 4 hours after treatment of previously untreated control rats with large-dose LPS. This was attenuated to 0.7 ± 0.04 nmol/min/g by an injection of low-dose LPS before challenge. This attenuation was time dependent; it failed to manifest at 12, 24, or 120 hours after low-dose LPS. Isolated endothelial cells, Kupffer cells, and sequestered hepatic neutrophils from rats given a high-dose LPS also generated significant amounts of superoxide both in the presence or absence of agonists, i.e., phorbol myristate acetate or opsonized zymosan. Pretreatment of rats with the low dose of LPS 48 hours before the large dose attenuated the spontaneous and primed release of superoxide by isolated nonparenchymal cells. Serum transaminase activities were also reduced in these LPS-tolerant rats. The suppressed oxygen-derived radical formation by the liver and nonparenchymal cells during acute LPS tolerance was associated with down-regulation of tumor necrosis factor (TNF) release in vivo. TNF has been shown to stimulate and prime neutrophils and Kupffer cells for increased respiratory burst. These results suggest that suppression of free radical formation may contribute to the amelioration of hepatic injury during acute endotoxin tolerance.
The development of anti-hepatitis C virus agents
Authors: Shimotohno Kunitada
Published: March 2007

We have built a model of the specificity pocket of the protease of hepatitis C virus on the basis of the known structures of trypsin-like serine proteases and of the conservation pattern of the protease sequences among various hepatitis C strains. The model allowed us to predict that the substrate of this protease should have a cysteine residue in position P1. This hypothesis was subsequently proved by N-terminal sequencing of two products of the protease. The success of this “blind” test increases our confidence in the overall correctness of our proposed alignment of the enzyme sequence with those of other proteases of known structure and constitutes a first step in the construction of a complete model of the viral protease domain.
Cellular immune responses in patients with dual infection of hepatitis B and C viruses: Dominant role of hepatitis C virus
Authors: Tsai Sun-Lung , Liaw Yun-Fan , Yeh Chau-Ting , Chu Chia-Ming , Kuo George C.
Published: March 2007

Several lines of evidence have suggested that immune mechanisms are involved in the pathogenesis of hepatitis B virus (HBV)— and hepatitis C virus (HCV)-related hepatitis. Study of patients with dual HBV and HCV infection raises the question of which is etiologically more relevant in determining the liver cell damage. To address this issue, proliferation of peripheral blood mononuclear cells (PBMCs) in response to a panel of HBV and HCV antigens was assayed in 13 patients with chronic dual hepatitis B and C, 7 patients with chronic hepatitis B, 7 patients with chronic hepatitis C, and 6 patients with hepatitis B surface antigen (HBsAg) carrier state. Although HBV or HCV hepatitis patients had a significant response to HBV or HCV antigens, respectively, the patients with dual hepatitis B and C exclusively responded to HCV antigens, but not to HBV antigens. One patient who was seropositive for both HBV-DNA and HCV-RNA showed a low response to HBV antigens initially but lost the response 3 months later and became responsive to more HCV antigens. These findings suggest that HCV has a dominant role in the immune response of the patients with dual HBV and HCV infection. (Hepatology 1995; 21:908-912.)
Hepatitis C virus RNA and liver histology in blood donors reactive to a single antigen by second-generation recombinant immunoblot assay
Authors: Zanella Alberto , Conte Dario , Prati Daniele , Mozzi Fulvio , Capelli Carmen , Zanuso Francesco , Fraquelli Mirella , Bosoni Patrizia , Vianello Luciana , Pappalettera Marco , Velio Pietro , Montagnolo Glanguido , Bianchi Paolo A. , Sirchia Girolamo
Published: March 2007

The clinical significance of single band reactivity (indeterminate pattern) at anti-hepatitis C virus (HCV) second-generation recombinant immunoblot assay (RIBA-2) was investigated in symptomless subjects with normal liver function tests to obtain data for their counseling and clinical management. Serum and hepatic HCV RNA were determined by the nested polymerase chain reaction, and liver histology was evaluated in 40 symptomless blood donors with stable indeterminate RIBA-2 pattern, including 38 reactive to c22-3. All but one had normal alanine aminotransferase (ALT) levels. Two new immunoblot tests, RIBA-3 and INNO-LIA HCV Ab III (LIA-III), which incorporate additional HCV antigens, were also done to assess whether they could identify the viremic subjects. Ten cases (25%, confidence interval 12 to 38) were HCV RNA positive. Three of the HCV RNA-positive and none of the HCV RNA-negative subjects had chronic hepatitis. RIBA-2 strong intensity of reaction (score >2+) was observed in all the HCV RNA-positive and in 12 HCV RNA-negative subjects. RIBA-3 and LIA-III gave positive results in 9 of 10 and 10 of 10 HCV RNA-positive, but also in 8 of 30 and 24 of 30 HCV RNA-negative subjects. A c-22-3 reactivity score of 4+ by RIBA-3 and E2/NS1 reactivity by LIA-III were both strongly associated with HCV RNA (P < .001). Based on relatively high prevalence of chronic hepatitis in our series (30%), apparently healthy subjects with stable indeterminate RIBA-2 pattern and HCV RNA positivity should be considered for liver biopsy independently of ALT profile. Reactivity to particular HCV antigens by third-generation tests helped to identify the subjects with current infection. (Hepatology 1995; 21:913-917.)
Deleterious influence of pyrazinamide on the outcome of patients with fulminant or subfulminant liver failure during antituberculous treatment including isoniazid
Authors: Durand François , Bernuau Jacques , Pessayre Dominique , Samuel Didier , Belaiche Jacques , Degott Claude , Bismuth Henri , Belghiti Jacques , Erlinger Serge , Rueff Bernard , Benhamou Jean Pierre
Published: March 2007

Isoniazid and pyrazinamide are well-known hepatotoxic drugs, often used in combination. The aim of this study was to assess the prognostic influence of pyrazinamide on the outcome of fulminant or subfulminant liver failure caused by antituberculous therapy. Eighteen patients with fulminant or subfulminant liver failure due to antituberculous therapy were studied. Nine patients received isoniazid and rifampicin without pyrazinamide (group 1), and nine patients received isoniazid and rifampicin together with pyrazinamide (group 2). The severity of fulminant and subfulminant liver failure, as judged by the prevalence of coma and the lowest level of factor V, was similar in the two groups. Spontaneous survival was greater in group 1 (eight of nine) than in group 2 (two of nine) (P < .02). The authors conclude that pyrazinamide co-administration was associated with an increased mortality in patients with fulminant or subfulminant hepatitis occurring during antituberculous therapy. In these patients, pyrazinamide administration and an interval of more than 15 days between the onset of antituberculous treatment and jaundice, combined with grade III encephalopathy and factor V below 20%, predicted death without liver transplantation. (Hepatology 1995; 21:929-932.)
Concentrations of apolipoproten AI, AII, and E in plasma and lipoprotein fractions of alcoholic patients: Gender differences in the effects of alcohol
Authors: Lin Renee C. , Miller Barbara A. , Kelly Timothy J.
Published: March 2007

Previous studies have shown that plasma levels of high-density lipoprotein (HDL) cholesterol and the two major protein components of HDLs, i.e., apolipoproteins AI and AII, were elevated in male alcoholic patients without serious liver injury. By contrast, alcohol effect on apolipoprotein E remains unclear. Apolipoprotein E is a major component of very low—density lipoprotein (VLDL) and a minor component of human high-density lipoprotein. It plays a critical role in lipoprotein metabolism through cellular lipoprotein receptors. Furthermore, previous works were carried out mostly with male subjects, whereas alcohol effects on serum apolipoproteins in female subjects have not yet been adequately addressed. In this study, we have raised antibodies specifically to recognize human apolipoprotein AI, AII, and E, respectively, to quantify apolipoprotein concentrations in plasma and lipoprotein fractions of male and female alcoholic patients. We have also measured plasma apolipoprotein concentrations in patients who had abstained from alcohol while in the hospital. Our results showed the following: (1) plasma concentrations of apolipoprotein AI and AII were significantly elevated yet plasma apolipoprotein E decreased (33%) significantly (P < .01) in male alcoholic patients; (2) apolipoprotein AI concentrations in female nondrinking control subjects were higher than in male controls, and the concentrations of apolipoprotein AI in female alcoholic patients were not significantly elevated over those of female controls; (3) similar to their male counterparts, female alcoholic patients exhibited higher plasma apolipoprotein AII and lower apolipoprotein E; (4) changes in plasma apolipoproteins seen here were most likely attributable to a direct effect of alcohol but not a secondary effect of mild liver injury; (5) changes in plasma apolipoprotein levels in alcoholic patients were reversible in 1 week after alcohol abstinence; and (6) the decrease of plasma apo E in alcoholic patients was indicated by the presence of apo E—deficient VLDL particles whereas the concentration of apo E in HDL particles of alcoholic patients remained unaffected.(Hepatology 1995; 21:942-949.)
Heparan sulfate proteoglycan expression in normal human liver
Authors: Roskams Tania , Moshage Han , de Vos Rita , Guido David , Yap Paul , Desmet Valeer
Published: March 2007

Because increasing evidence implicates heparan sulfate proteoglycans (HSPGs) as essential cofactors in receptor-growth factor interactions, in cell-cell recognition systems, and in cell-matrix adhesion processes and yet little is known about their cellular distribution pattern and cellular sources in liver tissue, we used monoclonal antibodies specific for the core proteins of syndecan1, 2, 3, 4, glypican, and perlecan to investigate their immunohistochemical expression in normal adult human liver biopsy specimens. Syndecan1 was expressed in sinusoidal endothelial cells, whereas the endothelium of the portal tract vessels was negative. Hepatocytes showed a membranous staining pattern of the sinusoidal and intercellular domain. Bile duct epithelial cells showed basolateral membrane positivity. Immunoreactivity for syndecan2 was seen in mesenchymal cells, accentuated around bile ducts. Syndecan3 showed intense staining of hepatic arterial and portal venous endothelial cells, of mesenchymal cells, and of Ito cells. Immunohistochemistry for syndecan4 showed a granular staining pattern of hepatocytes at their bile canalicular pole. Glypican showed weak positivity in portal tract mesenchymal cells and clear positivity in nerve bundles. Perlecan was present in Disse's space, in endothelial cells, in basement membranes surrounding bile ducts and vessels, in vessel walls, and in mesenchymal cells. The highly differential expression of these HSPGs in the different cell compartments of the liver, as well as in basement membranes and in Disse's space, suggests that each of these proteoglycans has a specific function in the interplay of cells, matrix molecules, growth factors, and proteinases.(Hepatology 1995; 21:950-958.)
Hepatobiliary disease in cystic fibrosis patients with pancreatic sufficiency
Authors: Waters Donna L. , Dorney Stuart F. A. , Gruca Margie A. , Martin Hugh C. O. , Howman-Giles Robert , Kan Alex E. , de Silva Merl , Gaskin Kevin J.
Published: March 2007

Focal and multilobular biliary cirrhosis are considered pathognomonic of cystic fibrosis (CF) and almost invariably have been reported in patients with steatorrhea. In contrast, patients with pancreatic sufficiency and normal absorption are considered less likely to develop liver or biliary tract problems. The authors report three patients with CF and pancreatic sufficiency, presenting with recurrent abdominal pain (unrelated to pancreatitis). All had common bile duct disease, one with multilobular cirrhosis and portal hypertension. Pancreatic sufficiency was proven by quantitative pancreatic stimulation tests, 3-day fecal fat analyses, and serum pancreatic isoamylases. All three patients had mild lung disease. Two were homozygous for the common ΔF508 mutation, and the other, a ΔF508 compound heterozygote. Hepatobiliary structure and function were determined by serial hepatobiliary scintigraphy, percutaneous transhepatic cholecystography, and biochemical liver function tests. Patients 1 and 3 had mild hepatomegaly, normal liver biochemistry, and distal common bile duct strictures. Patient 2 had a firm nodular liver with splenomegaly, abnormal liver biochemistry, and a cholangiographic appearance of sclerosing cholangitis. All have undergone operative treatment for persistent abdominal pain. These cases confirm the occurrence of common bile duct pathology and liver disease in patients with CF and pancreatic sufficiency. They demonstrate that liver and biliary tract disease can occur independently of the underlying disease severity and the presence of steatorrhea. Further, they suggest that obstruction of the biliary tract may be an additional factor in the evolution of liver disease in CF. (Hepatology 1995; 21:963-969.)
Progressive type of focal nodular hyperplasia characterized by multiple tumors and recurrence
Authors: Sadowski Daniel C. , Lee Samuel S. , Wanless Ian R. , Kelly James K. , Heathcote Jenny E.
Published: March 2007

Focal nodular hyperplasia (FNH) is usually a stable lesion that does not enlarge when studied for long periods of time; recurrence after resection has not been reported. We present a patient with a solitary FNH lesion that enlarged, was resected, and then recurred. A second resection was performed because of abdominal pain and disclosed multiple lesions, two of which were acutely infarcted. Thirty-two months later there was ultrasound evidence of further recurrence. Histology of the lesions showed the usual appearance of FNH with ducts and ductules in the central stalk regions but also some areas with minimal ductular differentiation and scanty connective tissue. Because of the clinical and histological appearance, the lesions in this patient were distinct from the usual type of FNH and merit the name “focal nodular hyperplasia, progressive type.” (Hepatology 1995; 21:970-975.)
Neopterin and soluble tumor necrosis factor receptor type I in alcohol-induced cirrhosis
Authors: Diez-Ruiz Antonio , Tilz Gernot P. , Gutierrez-Gea Francisco , Gil-Extremera Blas , Murr Christian , Wachter Helmut , Fuchs Dietmar
Published: March 2007

Alcohol-induced cirrhosis (AC) is accompanied by disturbances of immune function and cytokine production. To better define the pattern of cytokine synthesis in this disease and to relate it to the immune activation state, we measured circulating levels of soluble tumor necrosis factor receptor p55 (sTNFR-55) and neopterin in a group of 85 patients with AC (classified according to the Child-Pugh score of severity of liver disease) and 43 healthy volunteers. Serum concentrations of sTNFR-55 and neopterin were significantly raised in patients with AC. Moreover, concentrations of sTNFR-55 were significantly higher in patients with more severe disease compared with the group with lower severity. There were significant correlations between sTNFR-55 and neopterin levels in patients and controls. The results contribute to affirm the existence of an immune activation state in AC that could be responsible for the development of the disease and clinical complications. (Hepatology 1995; 21:976-978.)
Transjugular intrahepatic portal-systemic shunt in the treatment of refractory ascites: Effect on clinical, renal, humoral, and hemodynamic parameters
Authors: Quiroga Jorge , Sangro Bruno , Núñez Marina , Bilbao Ignacio , Longo Jesús , García-Villarreal Luis , Zozaya José M. , Betés Maite , Herrero José I. , Prieto Jesús
Published: March 2007

Seventeen cirrhotics with refractory ascites were treated with transjugular intrahepatic portosystemic shunt (TIPS) and followed for 15.5 ± 3.4 months. Five patients died, four within 3 months after TIPS (hepatocellular failure) and one after 22 months (cholangiocarcinoma). Six patients received transplants 1 to 10 months after the procedure. Actuarial survival at 6, 12, and 24 months was 75%, 75%, and 63%, respectively. Portosystemic venous pressure gradient decreased by 46% at 1 month and by 38% at 7 to 12 months. Eight patients presented 18 stenoses 1 to 18 months after TIPS. Twelve stenoses required balloon dilatation. Tense ascites was present before TIPS in 100% of the patients, whereas it was mild or absent in 56% at 1 month, in 66% at 3 to 6 months, in 57% at 7 to 12 months, and in 100% at 24 months after TIPS. Requirements for diuretics and paracentesis decreased after TIPS (P < .001, both). One month after TIPS, urinary and fractional sodium excretion increased (P < .001, both), plasma renin activity, plasma aldosterone (P < .005, both), and plasma norepinephrine (P < .05) decreased and cardiac output (P < .01) increased, systemic vascular resistances (P < .005) decreased, and arterial pressure did not change. Acute hepatic encephalopathy was frequent early after TIPS but was responsive to treatment and caused no long-term disability. In conclusion, TIPS is useful in the treatment of refractory ascites through lowering portal pressure and improving renal sodium excretion. This effect could be attributable to an increase in effective blood volume causing deactivation of vasopressor systems. (Hepatology 1995; 21:986-994.)
T-cell responses to the components of pyruvate dehydrogenase complex in primary biliary cirrhosis
Authors: Jones David E. J. , Palmer Jeremy M. , James Oliver F. W. , Yeaman Stephen J. , Bassendine Margaret F. , Diamond Austin G.
Published: March 2007

Primary biliary cirrhosis (PBC) is an autoimmune condition that results in destruction of the intrahepatic biliary epithelial cells and is characterized by autoantibodies to pyruvate dehydrogenase complex (PDC). The portal tract T-cell infiltrate and up-regulation of HLA class I, HLA class II, and cell adhesion molecules such as intercellular adhesion molecule-1 on the biliary epithelial cells suggest that T cells play a significant role in mediating this damage. The authors have characterized the peripheral blood T-cell proliferative responses of 24 PBC patients and 48 controls (20 normal, 28 non-PBC chronic liver disease) to the dominant autoantigen PDC, and its constituent components E1, E2 and protein X (which co-purify), and E3. A significant proportion of both PBC patients and controls showed T-cell responses to whole PDC (12 of 24 vs. 24 of 48 SI > 2.5 P = NS) and E1 (15 of 24 vs. 25 of 48 P = NS). Responses to PDC and E1 are thus seen in normal individuals and are not limited to PBC patients. T-cell responses to E2/X were seen in most PBC patients (14 of 24), but in only a small number of controls (6 of 48, P < .0001), responses to E2/X being significantly more frequent in pre-cirrhotic PBC patients (stages I to III, 12 of 15) than cirrhotic (stage IV, 2 of 9 P < .05). Peripheral blood T-cell responses to E2/X are thus strongly associated with early PBC. Responses to E3 were low in both PBC patients and controls. No differences were seen in responses to the control antigen tetanus toxoid between PBC patients and controls. These in vitro observations are compatible with the view that peripheral mechanisms may play a significant role in maintaining self-tolerance to PDC in the normal state, and that the expression of specific T-cell responses to PDC-E2/X in vivo in PBC patients may be a consequence of impairment of these mechanisms of peripheral tolerance. (Hepatology 1995; 21:995-1002.)
Interferon alfa and gamma inhibit proliferation and collagen synthesis of human ito cells in culture
Authors: Mallat Ariane , Preaux Anne-Marie , Blazejewski Sylvie , Rosenbaum Jean , Dhumeaux Daniel , Mavier Philippe
Published: March 2007

During the course of ongoing liver fibrogenesis, Ito cells acquire myofibroblastic features, proliferate, and synthesize increased amounts of extracellular matrix components. Interferon (IFN) alfa and IFN gamma have been shown to elicit antiproliferative and/or antifibrogenic effects in various cell cultures of mesenchymal origin. The aim of this study was to investigate the effects of IFN-α and IFN-γ on cultured human myofibroblastic Ito cells (MFBIC) proliferation and collagen synthesis and secretion. Serum-stimulated incorporation of [3H]-thymidine into DNA of MFBIC was dose-dependently decreased by both cytokines. IFN-α (104 U/mL) and IFN-γ (103 U/mL) decreased DNA synthesis by 69% and 66%, respectively. Inhibition of cell proliferation was confirmed by cell counting. Similar results were observed when cell growth was stimulated with platelet-derived growth factor (PDGF-BB, PDGF-AA) or transforming growth factor (TGF)-β1. Collagen secretion per cell was inhibited by both cytokines, as assessed by [3H]-hydroxyproline incorporation. After a 6-day treatment, IFN-γ showed a greater potency than IFN-α in inhibiting secretion of newly synthetized collagen (41% and 48% of control in the presence of 102 U/mL of IFN-γ and 104 U/ mL of IFN-α, respectively). Both IFN-α and IFN-γ concurrently decreased steady-state expression of type I and type III procollagen messenger RNAs (mRNAs) in quiescent MFBIC. Viability assays ruled out cytotoxic effects of the two molecules. Finally, both IFNs decreased smooth muscle α-actin (SMα-actin) expression, whether assayed by immunobloting or by Northern blot analysis. We conclude that IFN-α and IFN-γ inhibit proliferation as well as collagen synthesis in human MFBIC. (Hepatology 1995; 21:1003-1010.)
Pretransplantation clinical status and outcome of emergency transplantation for acute liver failure
Authors: Devlin John , Wendon Julia , Heaton Nigel , Tan Kai-Chah , Williams Roger
Published: March 2007

Emergency transplantation for acute liver failure has a significantly inferior outcome than transplantations performed for elective indications. The severity of the pretransplantation clinical illness in this group will contribute to the reduced patient survival. We have reviewed the outcome of our first 100 consecutive adult patients who received transplants for acute liver failure and have evaluated and determined which recipient clinical parameters present on admission and at transplantation act as risk factors in early posttransplantation outcome. In patients who received transplants for nonacetaminophen-induced liver failure (n = 79), no static variable determinable on admission (including age, sex, year of transplantation, hospital admission to transplantation period, and fulminant or late-onset presentation) other than cause was predictive of 2-month patient survival. Fulminant Wilson's disease and idiosyncratic drug reactions with 2-month survival rates of 100% and 12.5%, respectively, had significantly different outcomes from other causes. By the time of transplantation, of four dynamic variables significant in a univariate analysis (serum creatinine, encephalopathy grade, Apache 111 and organ system failure scores, and P values < .05), only the creatinine level was an independent variable in a stepwise logistic regression for 2-month survival (r = .33). In patients who received transplants for acetaminophen hepatotoxicity (n = 21), overdose to hepatectomy period was the only significant static variable, with no parameter predictive of outcome present on admission. Of two dynamic variables that were significant at transplantation (serum bilirubin and Apache 111 score, P < .05) only the latter parameter was an independent variable in the regression model (r = .51). Selection of candidates experiencing acute liver failure for transplantation depends on assessment of both the prognosis of the primary hepatic illness on admission and, for a successful outcome, the clinical status at the time of proposed grafting. (Hepatology 1995; 21:1018-1024.)
Influence of bezafibrate on hepatic cholesterol metabolism in gallstone patients: Reduced activity of cholesterol 7α-hydroxylase
Authors: Ståhlberg Dagny , Reihnér Eva , Rudling Mats , Berglund Lars , Einarsson Kurt , Angelin Bo
Published: March 2007

Bezafibrate is a hypolipidemic fibric acid derivative known to induce cholesterol supersaturation of bile. To characterize its effects on hepatic cholesterol metabolism, 31 normolipidemic, normal-weight patients with gallstones undergoing cholecystectomy were studied. Eleven patients (5 men) were randomized to treatment with bezafibrate, 200 mg three times daily for 4 weeks before operation; the remaining 20 patients (5 men) served as nontreatment controls. At operation, a liver biopsy specimen was obtained under standardized conditions and several important parameters of cholesterol metabolism were assayed. Bezafibrate treatment lowered total plasma cholesterol and triglycerides 30% and 37%, respectively. The hepatic cholesterol 7α-hydroxylasé activity was reduced by ≈60% in the bezafibrate treated patients compared with the controls, whereas the acyl-coenzyme A: cholesterol acyltransferase (ACAT) activity was similar in the two groups. The total 3-hydroxy-3-methylglutaryl coenzyme A (HMG CoA) reductase activity was increased twofold in the treated patients, whereas the active enzyme remained about the same as in the controls. The low-density lipoprotein (LDL) receptor binding activity was unaffected by the treatment. Bezafibrate treatment significantly reduces cholesterol 7α-hydroxylase activity, and it is suggested that this may play an important role for the development of supersaturated bile during such therapy. (Hepatology 1995; 21:1025-1030.)
Abnormal expression of the E2 component of the pyruvate dehydrogenase complex on the luminal surface of biliary epithelium occurs before major histocompatibility complex class II and BB1/B7 expression
Authors: Tsuneyama Koichi , van de Water Judy , Leung Patrick S. C. , Cha Sanghoon , Nakanuma Yasuni , Kaplan Marshall , de Lellis Ronald , Coppel Ross , Ansari Aftab , Gershwin Eric M.
Published: March 2007

Primary biliary cirrhosis (PBC) is a chronic autoimmune liver disease characterized histologically by non-suppurative destructive cholangitis. Sera from patients with PBC react with a series of intramitochondrial enzymes with the immunodominant response directed against the E2 component of the pyruvate dehydrogenase complex (PDC-E2). Recently, using tissue sections of late-stage PBC, we showed that there is increased expression in biliary epithelial cells of patients with PDC-E2 or a molecule cross-reactive with PDC-E2. Previous work has shown that biliary epithelial cells of patients with PBC express an increased amount of class II. To address the sequence of events in the evolution of PBC, we have focused our attention in this study on early biliary epithelial lesions. In particular, we have studied the liver of 22 female patients with PBC that was diagnosed as either stage I or stage II using both a mouse monoclonal antibody that has reactivity similar to human autoantibodies as well as a human Fab combinatorial prepared from the lymph node of a PBC patient. Tissues were simultaneously stained using antibodies to PDC-E2, class II, and BB1/B7. As a positive control, tissues from late-stage PBC were studied concurrently. By determining the order of expression among the three molecules, PDC-E2, class II, and BB1/B7, we report that the expression of PDC-E2 or a PDC-E2—like molecule on biliary duct epithelium of patients with PBC precedes the expression of BB1/B7 and major histocompatibility complex (MHC) class II molecules. The alteration of an autoantigen in biliary duct epithelium may be the earliest lesion in PBC. (Hepatology 1995; 21:1031-1037.)
Induction of metallothionein gene expression by epidermal growth factor and its inhibition by transforming growth factor-β and dexamethasone in rat hepatocytes
Authors: Moffatt Pierre , Plaa Gabriel L. , Denizeau Francine
Published: March 2007

Metallothionein (MT) is a small cysteine-rich protein thought to be mainly involved in metal regulation and detoxification. The implication of MT in cell growth and differentiation has also been suggested. This latter hypothesis was further investigated in adult rat hepatocytes induced to proliferate by epidermal growth factor (EGF). Exposure of hepatocytes to EGF resulted in significant increases (≈twofold) in MT protein and MT-1 messenger RNA (mRNA) levels, which were maximal after 48 hours. As revealed by nuclear run-on analysis, these changes were the result of transcriptional activation. Increases of MT occurred concomitantly with stimulation of DNA synthesis (48 hours). Addition of ZnSO4 or dexamethasone (Dex) was also effective at inducing MT protein (≈3.6 to 3.3 times) and mRNA. Combined addition of Zn and EGF produced an additive increase in MT protein and MT-1 mRNA levels. When both Dex and EGF were present together, the EGF-induced MT protein and mRNA expression was lost, whereas it had only minor inhibitory effects on DNA synthesis. Transforming growth factor beta (TGF-β), a known antagonist of EGF on hepatocytes, blocked the EGF-induced MT accumulation and stimulation of DNA synthesis. In addition, under the same conditions, the EGF-induced c-fos mRNA accumulation was blocked by Dex whereas TGF-β had no effect. These results show that growth factors believed to play a role in liver regeneration can also modulate MT gene expression in vitro. This modulation does not strictly parallel that of DNA synthesis. The possibility that c-fos stimulation may play a role in MT induction by EGF cannot be ruled out. (Hepatology 1995; 21:1038-1044.)
Modulation of macrophage functioning abrogates the acute hepatotoxicity of acetaminophen
Authors: Laskin Debra L. , Gardner Carol R. , Price Veronica F. , Jollow David J.
Published: March 2007

Acetaminophen is a mild analgesic and antipyretic agent that is safe and effective when taken in therapeutic doses. Ingestion of overdoses, however, may lead to acute liver failure accompanied by centrilobular degeneration and necrosis. Although the toxicity of acetaminophen is generally thought to be caused by direct interaction of its reactive metabolites with cellular macromolecules, recent studies have suggested that nonparenchymal cells also may contribute to tissue injury indirectly through the release of cytotoxic mediators. We analyzed the potential role of hepatic macrophages in acetaminophen hepatotoxicity by examining the effects of modulating the activity of these cells on tissue injury. Treatment of male Long Evans Hooded rats with acetaminophen (800 mg/kg) was found to induce extensive centrilobular hepatic necrosis. Pretreatment of the rats with either dextran sulfate or gadolinium chloride, two inhibitors of hepatic macrophage functioning, completely blocked hepatic necrosis, as well as increases in serum transaminase levels induced by acetaminophen. Interestingly, treatment of rats with the macrophage activator, lipopolysaccharide (LPS), also reduced tissue injury induced by acetaminophen. To exclude the possibility that the effects of gadolinium chloride, dextran sulfate, or LPS were due to alterations in acetaminophen metabolism, we analyzed the effects of these agents on various pharmacokinetic properties of this analgesic. Dextran sulfate and gadolinium chloride had no effect on the half-life of a low dose of acetaminophen (20 mg/kg), or on the activity of any of its individual pathways of metabolism, including the formation of acetaminophenmercapturic acid. LPS treatment of rats caused a general depression of acetaminophen metabolism involving all of the known pathways of metabolic clearance, resulting in a decrease in the blood half-life of the drug. However, the fraction of the dose converted to the toxic metabolite (NAPQI) was not different from that observed in rats given acetaminophen alone. Collectively, these data indicate that the protection afforded the animals by pretreatment with macrophage modulators was not due to suppression of the formation of NAPQI and hence support the hypothesis that macrophages may contribute directly to acetaminophen hepatotoxicity by an independent mechanism. (Hepatology 1995; 21:1045-1050.)
Biliary copper excretion in the neonatal rat: Role of glutathione and metallothionein
Authors: Mohan Parvathi , Failla Mark , Bremner Ian , Arthur-Smith Ann , Kerzner Benny
Published: March 2007

Metallothionein (MT) and glutathione (GSH) have been implicated as two major copper-binding agents involved in the hepatobiliary copper metabolism in the adult rat. This study was designed to explore their potential role in facilitating copper export from the copper-laden hepatocyte of the newborn rat. Biliary and hepatic copper, GSH, and immunoreactive MT-I concentrations were measured in Sprague-Dawley rats at 1, 2, 3, 4, and 8 weeks of age. Bile was collected by duct cannulation for 90 minutes before the rats were killed. Liver was removed, weighed, and freeze-dried. The bile flow rate (BFR) doubled and the liver weight increased 14-fold during maturation. Hepatic and biliary copper and MT-I concentrations were significantly higher in the suckling than in the weanling. The total biliary output of copper per 24 hours was low at 1 week and increased significantly by 8 weeks of age. MT-I-bound copper represented a maximum of only 3.4% of biliary copper at 1 week and 0.5% at 8 weeks. GSH was not detected in bile until 2 weeks and then increased 15-fold by 8 weeks, while hepatic GSH levels remained unchanged. Therefore, GSH levels did not correlate with the high biliary copper concentration at week 1, although there was a close correlation between the total daily biliary excretion of copper and GSH at 2 weeks and beyond. We conclude that the net biliary copper excretion per day is relatively low in the first week of life and is independent of MT and GSH secretion. It increases significantly once GSH is available in bile. We speculate that biliary copper excretion in the neonatal rat may involve copper binding agents as yet unidentified. (Hepatology 1995; 21:1051-1057.)
Structure-specific inhibition by bile acids of adenosine triphosphate—dependent taurocholate transport in rat canalicular membrane vesicles
Authors: Nishida Toshirou , Che Mingxin , Gatmaitan Zenaida , Arias Irwin M.
Published: March 2007

The adenosine triphosphate (ATP)-dependent transport system is a major determinant of canalicular bile acid secretion. The system transports bile acids and neither organic cations nor non—bile acid organic anions, such as glucuronides or glutathione adducts. To define the structural specificity of the ATP-dependent system, the authors examined the ability of various bile acids to inhibit ATP-dependent taurocholate transport by rat liver canalicular membrane vesicles. Only bile acids with a negative charge inhibited transport, which was unaffected by side chain length. Conjugated, but not unconjugated, mono- and di-hydroxy bile acids inhibited transport. The presence of 7α- and 12α-hydroxylation also influenced inhibition of ATP-dependent taurocholate transport. Inhibition of transport by bile acids was kinetically competitive. These results suggest that the canalicular ATP-dependent bile acid transport system depends on bile acid side chain charge, conjugation, and hydroxylation. (Hepatology 1995; 21:1058-1062.)
Effects of pentoxifylline pretreatment on Kupffer cells in rat liver transplantation
Authors: Kozaki Koichi , Egawa Hiroto , Bermudez Luiz , Keefe Emmet B. , So Samuel K. , Esquivel Carlos O.
Published: March 2007

Previous research with pentoxifylline (PTX), a methylxanthine phosphodiesterase inhibitor, suggests that this drug may be capable of suppressing the activation of Kupffer cells and thereby help decrease liver injury after transplantation. To investigate this possibility, the current study sought to determine whether the release of O2
− and tumor necrosis factor (TNF) from Kupffer cells in donor livers can be suppressed if the organs are exposed to PTX before preservation. In an in vitro experiment, rat livers were flushed with PTX (25 mg/kg body weight) in University of Washington (UW) solution or UW solution alone (control) and then and stored in UW solution for either 4 or 24 hours. Kupffer cells then were purified and their degree of activation determined by measuring O2
− release and the production of TNF after lipopolysaccharide stimulation. In an in vivo experiment, a group of rats underwent orthotopic liver transplantation with grafts prepared in the same manner as in the in vitro study. TNF and aspartate transaminase (AST) were measured in blood samples taken 3 hours and 24 hours after transplantation. Compared with controls, the Kupffer cells from grafts pretreated with PTX produced significantly less O2
− and TNF, and the recipients of PTX-pretreated grafts had lower levels of TNF and AST 3 hours after transplantation. The current data indicate that O2
− and TNF production in liver grafts is suppressed by PTX pretreatment. Through its suppressive effect on Kupffer cells, PTX may help minimize preservation-reperfusion injury and improve graft survival. (Hepatology 1995; 21:1079-1082.)