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C Degott

Publications and source records attributed to C Degott.

At least 127 records · Page 7Linked to original sources
PubMed1994

Expression of cytokine-dependent adhesion molecules in postreperfusion biopsy specimens of liver allografts.

BACKGROUND/AIMS: Allogeneic recognition of donor cells by host T lymphocytes requires the expression of cytokine-dependent molecules, such as class II major histocompatibility antigens, intracellular adhesion molecule 1 (ICAM-1), and lymphocyte function-associated antigen 3 (LFA-3). In the liver, activation of Kupffer cells after ischemic injury during the transplantation procedure may result in an early induction of cytokine-dependent molecules. METHODS: The pattern of induction of ICAM-1, HLA-DR, HLA-DQ, and LFA-3 was investigated in 30 postreperfusion surgical biopsy specimens of liver allografts by an immunohistochemical technique. RESULTS: Two patterns of induction were observed: focal or diffuse. On hepatocytes, ICAM-1 was induced in 22 cases (11 focal, 11 diffuse), HLA-DR in 18 cases (13 focal, 5 diffuse), HLA-DQ in 13 cases (3 focal, 10 diffuse), and LFA-3 in 1 case (focal). On bile duct cells, HLA-DR was expressed in 19 cases, associated with HLA-DQ in 7 cases. No induction of ICAM-1 and LFA-3 was detected. Compared with the other patients, the group of patients with diffuse postoperative hepatocellular induction of ICAM-1 was characterized by higher preharvesting serum transaminase levels in the donor (P < or = 0.001), suggestive of preoperative ischemic injury, and increased incidence of acute graft rejection (P = 0.04). CONCLUSIONS: Preoperative warm ischemia may modify the immunogenicity of liver allografts.

Adult↗
PubMed1994

Expression of cytokine-dependent immune adhesion molecules by hepatocytes and bile duct cells in chronic hepatitis C.

BACKGROUND/AIMS: The pathogenesis of liver cell injury in chronic hepatitis C is poorly understood. To test whether immune-mediated mechanisms might be involved in the pathogenesis of liver cell injury during infection by hepatitis C virus, the expression of cytokine-dependent immune molecules by hepatocytes and bile duct cells during chronic hepatitis C was studied. METHODS: In 35 patients, expression of class I and II HLA antigens, intercellular adhesion molecule (ICAM) 1, and lymphocyte function antigen (LFA) 3 was studied by immunohistochemistry and scored by a semiquantitative grading system. Statistical analysis was performed using Spearman's test and t test. RESULTS: Class I HLA antigens were induced on hepatocytes in 20 cases. In all cases, HLA-DR, ICAM-1, and/or LFA-3 were detected on hepatocytes in piecemeal necrosis and intralobular clusters. Bile duct cells expressed HLA-DR in 32 cases and ICAM-1 and LFA-3 in 14 cases. Expression levels of immune molecules on hepatocytes correlated with aminotransferase activity (P < 0.035), histological activity (P < 0.001), and score of necrosis (P < 0.01). ICAM-1 expression on hepatocytes was higher in patients with intraportal lymphoid nodules (P = 0.005). Expression levels of ICAM-1 and LFA-3 on bile ducts correlated with the severity of bile duct damage (P < 0.015). CONCLUSIONS: These results suggest the involvement of immune-mediated mechanisms in the pathogenesis of liver cell injury in chronic hepatitis C.

Adult↗
PubMed1994

Hepatotoxicity of germander in mice.

BACKGROUND/AIMS: An epidemic of hepatitis due to germander teas or capsules recently occurred in France. The aim of the present study was to show the hepatotoxicity of germander and determine its mechanism in mice. METHODS: A germander tea lyophilisate and a fraction that isolated and concentrated 10-fold the furano neo-clerodane diterpenoids of the lyophilisate were prepared. RESULTS: (1) Intragastric administration of the lyophilisate (1.25 g/kg) or the furano neo-clerodane diterpenoid fraction (0.125 mg/kg) produced similar midzonal liver cell necrosis at 24 hours in mice. (2) Toxicity was prevented by pretreatment with a single dose of troleandomycin (a specific inhibitor of cytochromes P4503A) and enhanced by pretreatment with dexamethasone or clotrimazole (two inducers of cytochromes P4503A). (3) Toxicity was attenuated by pretreatment with butylated hydroxyanisole or clofibrate (two inducers of microsomal epoxide hydrolase) and markedly increased by phorone-induced glutathione depletion. CONCLUSIONS: We conclude that germander constituents (probably its furano neo-clerodane diterpenoids) are transformed by cytochromes P450 (particularly P4503A) into hepatotoxic metabolites. The metabolites (probably epoxides) are partly inactivated by glutathione and probably epoxide hydrolase.

Alanine Transaminase↗
PubMed1994

The changing scene of hepatic vein thrombosis: recognition of asymptomatic cases.

BACKGROUND/AIMS: Hepatic vein thrombosis is thought to be manifested by ascites, abdominal pain, and hepatomegaly, with a uniformly poor prognosis. However, new imaging techniques allow for the diagnosis of hepatic vein thrombosis in asymptomatic cases. The aim of our study was to re-evaluate symptoms and prognosis in patients with hepatic vein thrombosis. METHODS: Eighty-one patients with hepatic vein thrombosis were analyzed. Forty-seven patients were admitted from 1970 to June 1987 (group I, before Doppler ultrasonography and magnetic resonance imaging were introduced at our hospital) and 34 from July 1987 to June 1991 (group II). RESULTS: When comparing the two groups, age, sex ratio, and causes of hepatic vein thrombosis did not differ. Eight group II patients (asymptomatic patients) had no ascites, hepatomegaly, or abdominal pain. One major hepatic vein remained patent in 41% of group II patients, compared with 12% in group I (P < 0.05). Intrahepatic collaterals were seen in 79% of group II patients, compared with 21% of group I patients (P < 0.01). All asymptomatic patients had large intrahepatic and portasystemic collaterals. At 3 years, death occurred in 22% of group II patients and in 45% of group I patients. No asymptomatic patient died. CONCLUSIONS: Asymptomatic hepatic vein thrombosis is associated with the spontaneous development of large intrahepatic and portosystemic collaterals. In asymptomatic patients, prognosis at 3 years seems to be good, and surgical therapy may not be required.

Adult↗
PubMed1994

Adenomatous hyperplasia of the liver in a patient with congenital hepatic fibrosis.

We report the case of a 30-year-old man suffering from congenital hepatic fibrosis, who was treated at age 12 by splenorenal shunt for portal hypertension, and who developed numerous, large hepatic nodules. The patient underwent liver transplantation because of recurrent episodes of acute cholangitis and the presence of foci of dysplasia in the nodules. Histological examination of the surgical specimen showed adenomatous hyperplastic nodules with a few atypical foci in an otherwise fibrous but non-cirrhotic liver. Such lesions have not yet been described in congenital hepatic fibrosis. The respective roles of congenital hepatic fibrosis and splenorenal shunts in the development of these nodules are discussed.

Adult↗
PubMed1994

Etiology of chronic hepatitis in France: predominant role of hepatitis C virus.

The aim of this study was to assess the causes of histologically proven chronic hepatitis in a series of 357 consecutively admitted patients. Patients with chronic alcohol intake above 50 g per day, Wilson's disease, idiopathic hemochromatosis or homozygous alpha-1 antitrypsin deficiency were excluded. Sera of all patients were tested for antibodies to hepatitis C virus with second-generation enzyme-linked immunoassay and recombinant immunoblot assay, for markers of hepatitis B and hepatitis D viruses, and for autoantibodies. Detection of hepatitis C viral RNA by polymerase chain reaction was attempted if recombinant immunoblot assay was indeterminate, or if both viral and autoimmune markers were absent. If no serum markers, including HCV RNA, were found, the cause of chronic hepatitis was considered as unknown. The cause of chronic hepatitis was found in 343 cases (96.4%), including three patients with HCV RNA as the only marker. Chronic hepatitis was related to hepatitis C virus in 51.8%, to hepatitis B virus in 32.8% (including hepatitis D infection in 3.1%), and to autoimmune hepatitis in 5.9% of cases, respectively. No case of drug-induced chronic hepatitis was observed in this series, and in 5.9% of cases, there were probably multiple causes. Finally, in 3.6% of the cases the cause of chronic hepatitis remained unknown despite extensive evaluation suggesting the existence of a non-A, non-B, non-C viral agent.

Adult↗
PubMed1994

Flow cytometry CD4+/CD8+ ratio of liver-derived lymphocytes correlates with viral replication in chronic hepatitis B.

T lymphocytes have been assumed to play an essential role in tissue injury in patients with chronic hepatitis B. As hepatitis B virus (HBV) is considered as a major factor controlling liver inflammation, we assessed whether a particular T lymphocyte subset could be preferentially detected in the liver in accordance with viral replication. Liver-derived lymphocytes and peripheral blood lymphocytes were analysed by flow cytometry in 21 patients with histologically confirmed chronic hepatitis B without cirrhosis. Viral replication was quantified by hybridization of serum HBV DNA. Eleven patients exhibited an active viral replication with serum HBV DNA ranging from 10 to 388 pg/ml at the time of the liver biopsy, whereas 10 patients had no detectable serum HBV DNA. In patients exhibiting viral replication, CD4+/CD8+ ratios of liver-derived lymphocytes were significantly higher (P < 0.05) than those obtained in patients without viral replication. In contrast, the percentage of T cells expressing the gamma/delta receptor and that of CD2+/CD57+ cells were similar in both groups of patients. Furthermore, in patients exhibiting viral replication, CD4+CD8+ ratios of liver-derived lymphocytes correlated with serum HBV DNA levels (P < 0.001). No relationship between CD4+/CD8+ ratio of liver-derived and peripheral blood lymphocytes was observed. Our data indicate that, in patients with chronic hepatitis B, the CD4+/CD8+ ratio of liver-derived lymphocytes correlates with viral replication. This suggests that in situ helper/inducer CD4+ T lymphocytes may positively regulate the cytotoxic T cell activity in patients with HBV-related chronic hepatitis.

Adult↗
PubMed1994

Long-term histologic and viral changes in patients with chronic hepatitis C who responded to alpha interferon.

We assessed the long-term outcome in 24 patients with chronic hepatitis C who responded to alpha interferon. All patients were followed up for 12 months, and 16 patients were followed up 41 +/- 9 months. During the follow-up period, 18 of the 24 patients (75%) relapsed (serum ALT levels increased again); 16 had an early relapse within the 6 months and two had a late relapse 21 and 36 months after therapy; one cirrhotic patient with relapse died. Serum HCV RNA remained detectable in the two patients before the late relapse and in three of the six patients with sustained biochemical response. Histologic assessment 13 to 31 months after therapy showed a decrease in activity in most patients, even in some of those with relapse, but the decrease in portal inflammation was more marked (p < 0.05) in patients with sustained biochemical response. Liver HCV RNA was not detectable in the two sustained responders who were negative for serum HCV RNA. Despite biochemical remission induced by interferon therapy, HCV replication persists in many patients with a potential risk of late relapse. In contrast, some patients have no long-term detectable HCV RNA, suggesting clearance of HCV. Long-term histologic improvement of portal inflammation in most patients confirms the beneficial effect of interferon.

Adult↗
PubMed1994

Biliary obstruction resulting from Strongyloides stercoralis infection. Report of a case.

Hepatobiliary manifestations of strongyloidiasis are rare. A case is described of biliary obstruction associated with the presence of Strongyloides stercoralis in the duodenal mucosa and 250 microns rhabditiform larvae in bile. Biliary obstruction resulted from papillary stenosis, which resolved after treatment with thiabendazole. It is proposed that papillary stenosis may be responsible for obstructive jaundice associated with Strongyloides stercoralis infection, and that strongyloidiasis should be added to the causes of papillary stenosis.

Adult↗
PubMed1994

Liver-specific expression and high oncogenic efficiency of a c-myc transgene activated by woodchuck hepatitis virus insertion.

The high oncogenic efficiency of woodchuck hepatitis virus (WHV) has been correlated with the ability of this virus to provoke insertional activation of myc family genes. To assess the impact of viral integration on liver cell transformation, we have generated transgenic mice carrying the mutated c-myc gene and adjacent viral DNA from a woodchuck tumor, in original configuration. Virtually all mice from two different strains developed hepatocellular carcinoma with a mean latency period of 8-12 months. The c-myc transgene was expressed transiently in neonatal livers, and re-expressed at preneoplastic and neoplastic stages in adult livers. Woodchuck c-myc mRNA driven by the normal P1 and P2 promoters and WHV-specific transcripts encoding viral surface antigens were produced in a strictly co-regulated fashion during development and tumorigenesis, indicating a predominant regulatory influence of the viral enhancer. Furthermore, the activity of the viral enhancer in response to various biological stimuli was apparently modulated by glucose uptake and glucagon/insulin balance in differentiated hepatocytes. In this model, a viral integration event selected from a naturally occurring tumor proved to be determinant for induction of hepatocarcinogenesis, although enforced, liver-specific expression of c-myc was limited to a particular developmental stage.

Animals↗
PubMed1993

Chronic non-B, non-C hepatitis among blood donors assessed with HCV third generation tests and polymerase chain reaction.

Forty five blood donors with increased serum aminotransferases levels had liver histologic assessment and were tested for antibodies to hepatitis C virus (anti-HCV) with second and third generation ELISAs and RIBAs, and for HCV RNA with polymerase chain reaction (PCR) in serum and liver tissue. Twenty-nine of these 45 donors (65%) had steatosis without chronic hepatitis. Sixteen (35%) had chronic hepatitis. Twelve had evidence of HCV infection. Four had no evidence of HCV infection demonstrable by ELISA, RIBA or PCR. These four patients had no known cause of chronic hepatitis and no risk factor for parenterally acquired viral infection was found in them. This observation supports the hypothesis that a non-B, non-C virus might be implicated in chronic hepatitis. However, this hypothesis remains to be demonstrated.

Blood Donors↗
PubMed1993

Hepatitis C virus infection in anti-HIV positive and negative French homosexual men with chronic hepatitis: comparison of second- and third-generation anti-HCV testing.

To determine the prevalence of hepatitis C virus (HCV) infection in homosexuals with chronic hepatitis, we tested for anti-HCV antibodies 113 (47 anti-HIV positive) French non-drug-addicted homosexual men admitted for chronic viral hepatitis. Anti-HCV were detected with second- and third-generation ELISAs (ELISA2 and ELISA3) and RIBAs (RIBA2 and RIBA3). Chronic hepatitis was related to non-A, non-B infection in four, to hepatitis D virus (HDV) infection in five and to hepatitis B virus (HBV) infection in 104 patients. Anti-HCV positivity was found in 50.4% and 12.4% of the 113 patients, with ELISA2 and ELISA3, respectively. Positivity with RIBA2 and RIBA3 was found in only six of the 57 ELISA2 positive patients (all six were ELISA3 positive). The high prevalence of positivity with ELISA2 not confirmed by RIBA2 or RIBA3 suggests false-positive results. ELISA2 positive results were more frequent with frozen serum samples than with fresh serum samples (62% vs 23.5%, p = 0.0003). However, even with fresh serum, ELISA2-positive RIBA-negative results remained frequent in anti-HIV positive patients. ELISA3 seems to give more specific results. We conclude that the prevalence of HCV infection, as assessed with RIBA, was 5.3% among French homosexual men with chronic hepatitis (3.8% after exclusion of transfused patients). This low prevalence suggests that homosexual transmission of HCV is relatively uncommon.

Adult↗
PubMed1993

Increased ethane exhalation, an in vivo index of lipid peroxidation, in alcohol-abusers.

Ethane exhalation was measured in 42 control subjects, 52 patients with various non-alcoholic liver diseases, and 89 alcohol abusers who had been admitted to hospital for alcohol withdrawal and assessment of liver disease (six with normal liver tests, 10 with steatosis with or without fibrosis, six with alcoholic hepatitis, 29 with cirrhosis, 34 with both cirrhosis and alcoholic hepatitis, and four with both cirrhosis and a hepatocellular carcinoma). Ethane exhalation was similar in control subjects and in patients with non-alcoholic liver diseases, but was five times higher in alcohol abusers. Ethane exhalation in alcohol abusers was significantly, but very weakly, correlated with the daily ethanol intake before hospital admission, and the histological score for steatosis, but not with the inflammation or alcoholic hepatitis scores. Ethane exhalation was inversely correlated with the duration of abstinence before the test. In nine alcoholic patients, the exhalation of ethane was measured repeatedly, and showed slow improvement during abstinence. Ethane exhalation was significantly but weakly correlated with the Pugh's score in patients with alcoholic cirrhosis. It is concluded that the mean ethane exhalation is increased in alcohol abusers. One of the possible mechanisms may be the presence of oxidizable fat in the liver. The weak correlation with the Pugh's score is consistent with the contribution of many other factors in the progression to severe liver disease.

Adult↗
PubMed1993

[Fatal fulminant hepatitis induced by nilutamide (Anandron)].

The first case of fatal fulminant hepatitis probably caused by nilutamide, a non steroidal antiandrogen derivative, is reported. Nilutamide administration had been continued for 6 days after the occurrence of jaundice, 52 days after beginning of treatment. The rapidly fatal outcome might have been promoted by coadministration of phenobarbital.

Adenocarcinoma↗
PubMed1993

The intraportal lymphoid nodule and its environment in chronic active hepatitis C: an immunohistochemical study.

Intraportal lymphoid nodules have been observed in liver biopsy specimens from patients with autoimmune liver disease and chronic active hepatitis C. They are characterized by a nodular lymphocyte aggregate with a germinal center. The purpose of this in situ immunophenotyping study was to determine immunohistochemically the phenotype of immunocompetent cells in and around intraportal lymphoid nodules in patients with chronic hepatitis C. For comparison, we also examined lymphoid nodules in patients with autoimmune liver disease. Liver biopsy specimens from 13 unselected patients with CAH and hepatitis C antibodies and from 7 unselected patients with autoimmune liver disease seen during the same period were studied. Sections of snap-frozen specimens were immunostained with monoclonal antibodies directed against different subsets of T cells, B cells, follicular dendritic cells and macrophages. Intraportal lymphoid nodules were observed in 11 of 13 patients with chronic hepatitis C. They appeared as lymphoid follicles with activated B cells in germinal centers surrounded by a follicular dendritic cell network. A mantle zone of B cells was present around the aggregate of activated B cells. A T-cell zone comprising CD4-positive helper T cells, CD8-positive suppressor/cytotoxic T cells and a few CD25-positive activated T cells expressing interleukin-2 receptor was seen at the periphery of the nodules. Human leukocyte antigen DR was expressed by B cells and by T cells, indicating that T cells were activated. The immunocompetent cells observed in piecemeal necrosis were predominantly CD4 helper T cells, whereas those seen in the lobule were predominantly CD8 suppressor/cytotoxic T cells.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

Demonstration of hepatitis B virus DNA by polymerase chain reaction in the serum and the liver after spontaneous or therapeutically induced HBeAg to anti-HBe or HBsAg to anti-HBs seroconversion in patients with chronic hepatitis B.

The objective was to determine the proportion of patients with chronic hepatitis B in whom hepatitis B virus DNA is demonstrated by polymerase chain reaction after HBeAg to anti-HBe or HBsAg to anti-HBs spontaneous or therapeutically induced seroconversion. Polymerase chain reaction was performed on serum 6 and 12 mo after HBeAg to anti-HBe seroconversion in 12 patients and 2, 6 and 12 mo after HBsAg to anti-HBs seroconversion in 13 patients. Polymerase chain reaction was performed on liver tissue after HBeAg to anti-HBe seroconversion in five patients and after HBsAg to anti-HBs seroconversion in one patient. Serum HBV DNA was demonstrated by polymerase chain reaction in 83% of patients 6 or 12 mo after HBeAg to anti-HBe seroconversion and in 58%, 31% and 15% of patients at 2, 6 and 12 mo, respectively, after HBsAg to anti-HBs seroconversion. Liver HBV DNA was demonstrated by polymerase chain reaction in all patients tested. Our results show that (a) a reduced level of hepatitis B virus replication persists in most of the patients after HBeAg to anti-HBe seroconversion and might be predictive of reactivation, and (b) in contrast, hepatitis B virus replication progressively disappears in most of the patients after HBsAg to anti-HBs seroconversion.

Adult↗