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C Trepo

Publications and source records attributed to C Trepo.

At least 73 records · Page 4Linked to original sources
PubMed1999

Protective and therapeutic effect of DNA-based immunization against hepadnavirus large envelope protein.

BACKGROUND & AIMS: Studies in the murine model suggest that injection of DNA encoding hepatitis B virus structural proteins is promising for the induction of a specific immune response. We used the duck hepatitis B virus (DHBV) model to study the protective and therapeutic effects of naked DNA immunization against hepadnaviral large envelope protein. METHODS: A pCI-preS/S plasmid expressing the DHBV large protein was used for intramuscular immunization of ducks. The humoral response was tested by enzyme-linked immunosorbent assay, immunoblotting, neutralization, and in vivo protection tests. For DNA therapy, DHBV-carrier ducks received four injections of this plasmid. Viremia was monitored for 10 months; thereafter, liver biopsies were performed. RESULTS: Immunization with pCI-preS/S plasmid induced a specific, long-lasting, neutralizing, and highly protective anti-preS humoral response in uninfected animals. After pCI-preS/S treatment, a significant and sustained decrease in serum and liver DHBV DNA was observed for carrier ducks compared with the controls. CONCLUSIONS: DNA immunization against DHBV large protein results in a potent and protective anti-preS response in the duck model. The results of long-term follow-up of DNA-treated chronically infected ducks are promising and show the usefulness of this model for the study of genetic immunization in chronic hepatitis B therapy.

Animals↗
PubMed1999

Waterborne outbreak of intestinal microsporidiosis in persons with and without human immunodeficiency virus infection.

Among 1454 persons whose stool samples (n=5692) were submitted to a reference laboratory for microsporidia assessment from 1993 to 1996, microsporidia were identified in 338 persons: 261 persons infected with human immunodeficiency virus (HIV), 16 transplant patients, and 61 others. Intestinal microsporidiosis appears to be an endemic disease in HIV-positive persons (prevalence, 0.1%) and a sporadic disease in HIV-negative persons (prevalence, <1/1 million). A waterborne outbreak in 200 persons (attack rate, 1% in HIV-positive patients/month) occurred in the 1995 summer, without evidence of fecal contamination of water. No explanation was found before the outbreak ended, several months before the antiprotease era. Factors associated with microsporidiosis diagnosis were HIV infection, male homosexuality, low CD4 cell counts, and diarrhea. The major factor associated with a diagnosis of microsporidiosis during the outbreak was living in an area corresponding to one of the three water distribution subsystems of the town. Lake contamination was suspected.

Adult↗
PubMed1999

Detection of Pneumocystis carinii DNA in blood specimens from human immunodeficiency virus-infected patients by nested PCR.

The detection of Pneumocystis carinii DNA in blood by PCR could be useful for studying the natural history of pneumocystosis and could also be a noninvasive diagnostic method. The results of previous studies are nevertheless conflicting. In our study, we compared three commercially available DNA extraction kits (GeneReleaser, QIAamp Tissue Kit, and ReadyAmp Genomic DNA Purification System) and proteinase K and proteinase K-phenol-chloroform treatments for the extraction of P. carinii DNA from dilutions of a P. carinii f. sp. hominis cyst suspension mixed with human whole blood. A rapid and simple nested PCR protocol which amplifies a portion of the mitochondrial large-subunit rRNA gene was applied to all the extraction products. The QIAmp Tissue Kit was the most effective kit for the isolation of amplification-ready P. carinii DNA and was used with nested PCR for the testing of whole-blood specimens from 35 immunocompetent control patients and 84 human immunodeficiency virus (HIV)-infected patients investigated for pulmonary disease and/or fever. In HIV-infected patients, P. carinii DNA was detected by nested PCR in blood samples from 3 of 14 patients with microscopically proven P. carinii pneumonia, 7 of 22 patients who were considered to be colonized with P. carinii, and 9 of 48 patients who were neither infected nor colonized with P. carinii. P. carinii DNA was not detected in blood specimens from the 35 immunocompetent patients. P. carinii DNA in blood might represent viable P. carinii organisms or DNA complexes released from pulmonary phagocytes. In conclusion, P. carinii DNA may be detected in whole blood from HIV-infected patients, but the nature and the meaning of the circulating form of P. carinii remain to be established.

AIDS-Related Opportunistic Infections↗
PubMed1999

Hepatitis C virus recurrence after liver transplantation.

Cirrhosis due to hepatitis C virus (HCV) is now the most common indication of liver transplantation in Western Europe and the United States. In the absence of effective prophylaxis, recurrent HCV infection is almost inevitable. Though the natural history and intermediate term outcome of recurrent HCV are now better documented, those factors which may influence the recurrence of hepatitis and consequent progression of graft disease remain unclear. Interferon (IFN) as a sole agent for the treatment of recurrent infection has proved unsatisfactory. Early intervention with a combination of IFN and ribavirin seems promising, and this approach may prevent or delay progression of HCV related graft disease after liver transplantation.

Hepatitis C↗
PubMed1999

Recurrence of hepatocellular carcinoma as a mixed hepatoblastoma after liver transplantation.

BACKGROUND: Hepatoblastoma is an exceptional cause of primary malignant liver tumour in the adult. PATIENT: The case is reported of an adult patient transplanted for alcoholic cirrhosis complicated by multifocal hepatocellular carcinoma in whom a recurrence in the form of a mixed hepatoblastoma invading the whole transplanted liver developed three months after liver transplantation. METHODS: Complete clinical, histopathological, and immunohistochemical data were reviewed. RESULTS: The recurrent tumour invaded the whole liver. The major component was a mixed hepatoblastoma, with an epithelial component expressing cytokeratin and a mesenchymal component expressing vimentin. The tumour also contained a minor hepatocarcinomatous component expressing alpha fetoprotein. The rapid growth of the tumour prevented any attempt at treatment. Although direct evidence is lacking, the most likely hypothesis to explain the observations is a marked phenotypic change in the initial malignant population at recurrence. CONCLUSION: This case supports a possible filiation between hepatocellular carcinoma and hepatoblastoma in adults.

Carcinoma, Hepatocellular↗
PubMed1999

New antiviral agents for the therapy of chronic hepatitis B virus infection.

The development of new antiviral strategies for the treatment of chronic hepatitis B remains a major goal since hepatitis virus (HBV) is resistant to interferon treatment as well as to new nucleoside analogs. HBV is a small DNA virus that replicates its genome via a reverse transcription step. The viral polymerase has been the main viral target that was studied to design new antiviral treatments. Active research has led to the discovery of new nucleoside analogs that are potent inhibitors of the viral reverse transcriptase. Among them, lamivudine has also proven antiviral efficacy in clinical trials with a sustained inhibition of viral replication. However, due to the kinetics of viral clearance, long-term antiviral therapy is necessary to eradicate viral infection. These prolonged regimens are associated with the emergence of drug-resistant strains that harbor mutations in the viral polymerase gene within the conserved B and C domains. New approaches using combinations of nucleoside analogs or other strategies, such as immune intervention (DNA vaccine, stimulation of the TH1 response ) or gene therapy (antisense oligonucleotides, dominant negative mutants), should therefore be evaluated in animal models to optimize the current antiviral protocols.

2-Aminopurine↗
PubMed1999

[General practice patterns in hepatitis C virus mass screening in the Lyons region].

A study on the screening practices for hepatitis C was carried out among a sample of 786 general practitioners in the Lyon region. The sample comprised three groups: 272 doctors who had participated in a study of this screening, 242 doctors who had not responded to the request for participation, and 272 doctors who had refused to participate. Overall, 88.5% of the doctors surveyed had prescribed at least one HCV serology in the last 12 months, 82% had at least one HCV positive patient and of them, 59.3% had partly or completely screened these patients. The only differences between the three groups are related either to their belonging to an HIV or drug addict care network, or to a particular medical practice (study of allergies, sexology, nutrition, etc.). In fact, the first prescribe more among groups at risk and the second prescribe less and have fewer HCV positive patients.

Factor Analysis, Statistical↗
PubMed1998

Interferon alfa-2b alone or in combination with ribavirin for the treatment of relapse of chronic hepatitis C. International Hepatitis Interventional Therapy Group.

BACKGROUND: Interferon alfa is the only effective treatment for patients with chronic hepatitis C. Forty percent of patients have an initial response to this therapy, but most subsequently relapse. We compared the effect of interferon alone with that of interferon plus oral ribavirin for relapses of chronic hepatitis C. METHODS: We studied 345 patients with chronic hepatitis C who relapsed after interferon treatment. A total of 173 patients were randomly assigned to receive standard-dose recombinant interferon alfa-2b concurrently with ribavirin (1000 to 1200 mg orally per day, depending on body weight) for six months, and 172 patients were assigned to receive interferon and placebo. RESULTS: At the completion of treatment, serum levels of hepatitis C virus (HCV) RNA were undetectable in 141 of the 173 patients who were treated with interferon and ribavirin and in 80 of the 172 patients who were treated with interferon alone (82 percent vs. 47 percent, P<0.001). Serum HCV RNA levels remained undetectable 24 weeks after the end of treatment in 84 patients (49 percent) in the combination-therapy group, but in only 8 patients (5 percent) in the interferon group (P<0.001). Sustained normalization of serum alanine aminotransferase concentrations and histologic improvement were highly correlated with virologic response. Base-line serum HCV RNA levels of 2 x 10(6) copies per milliliter or less were associated with higher rates of response in both treatment groups. Viral genotypes other than type 1 were associated with sustained responses only in the combination-therapy group. Combined therapy caused a predictable fall in hemoglobin concentrations but otherwise had a safety profile similar to that of interferon alone. CONCLUSIONS: In patients with chronic hepatitis C who relapse after treatment with interferon, therapy with interferon and oral ribavirin results in higher rates of sustained virologic, biochemical, and histologic response than treatment with interferon alone.

Adult↗
PubMed1998

Randomised trial of interferon alpha2b plus ribavirin for 48 weeks or for 24 weeks versus interferon alpha2b plus placebo for 48 weeks for treatment of chronic infection with hepatitis C virus. International Hepatitis Interventional Therapy Group (IHIT)

BACKGROUND: Only 15-20% of patients with chronic hepatitis C achieve a sustained virological response with interferon therapy. The aim of this study was to compare the efficacy and safety of interferon alpha2b in combination with oral ribavirin with interferon alone, for treatment of chronic infection with hepatitis C virus (HCV). METHODS: 832 patients aged 18 years or more with chronic HCV who had not been treated with interferon or ribavirin, were enrolled and randomly allocated one of three regimens: 3 mega units (MU) interferon alpha2b three times a week plus 1000-1200 mg ribavirin per day for 48 weeks; 3 MU interferon alpha2b three times a week plus 1000-1200 mg ribavirin per day for 24 weeks; or 3 MU interferon alpha2b three times a week and placebo for 48 weeks. All patients were assessed for safety, tolerance, and efficacy at the end of weeks 1, 2, 4, 6, and 8, and every 4 weeks during treatment. After treatment was completed patients were followed up on weeks 4, 8, 12, and 24. The primary endpoint was loss of detectable HCV-RNA (serum HCV-RNA <100 copies/mL) at week 24 after treatment. FINDINGS: Sustained virological response at 24 weeks after treatment, was found in 119 (43%) of the 277 patients treated for 48 weeks with the combination regimen, 97 (35%) of the 277 patients treated for 24 weeks with the combination regimen (p=O.055), and 53 (19%) of the 278 patients treated for 48 weeks with interferon alone (p<0.001 vs both combination regimens, intention-to-treat analysis). Logistic regression identified five independent factors significantly associated with response: genotype 2 or 3, viral load less than 2 million copies/mL, age 40 years or less, minimal fibrosis stage, and female sex. Among patients with fewer than three of these factors the odds ratio of sustained response was 2.6 (95% Cl 1.4-4.8; p=0.002) for the 48 week combination regimen compared with 24 weeks of the combination regimen. Discontinuation of therapy for adverse events was more frequent with combination (19%) and monotherapy (13%) given for 48 weeks than combination therapy given for 24 weeks (8%). INTERPRETATION: An interferon alpha2b plus ribavirin combination is more effective than 48 weeks of interferon alpha2b monotherapy and has an acceptable safety profile. Patients with few favourable factors benefit more from extending the duration of combination therapy to 48 weeks.

Administration, Oral↗
PubMed1998

[Pretreatment with prednisolone enhances the effect of human lymphoblastoid interferon in chronic hepatitis B].

Patients (n = 213) with chronic hepatitis B were randomised to prednisolone (two weeks of 0.6 mg/kg/day, one week of 0.45 mg/kg/day and one week of 0.25 mg/kg/day) or placebo followed by two weeks rest, and were then given human lymphoblastoid interferon 10 MU daily for five days followed by 10 MU thrice weekly for 11 weeks. There were statistically significant effects of prednisolone pre-treatment on both HBeAg disappearance and HBeAg to anti-HBe seroconversion (log rank test statistics 5.43; p = 0.02 and 4.75; p = 0.03). HBeAg disappearance and HBeAg to anti-HBe seroconversion rates were 28 vs. 44% and 23 vs. 38% (placebo vs. prednisolone). Fifteen patients (7.5%) lost HBsAg. Three out of 22 cirrhotic patients (14%), one of whom received prednisolone pre-treatment, developed hepatic decompensation with a fatal outcome. Prednisolone pre-treatment, enhances the effect of lymphoblastoid interferon in chronic hepatitis B. Interferon treatment (with and without prednisolone) should be used with caution in patients with cirrhosis and avoided in patients with evidence of hepatic decompensation.

Adult↗
PubMed1998

Phosphorylation of DHBV pre-S: identification of the major site of phosphorylation and effects of mutations on the virus life cycle.

Four potential serine/threonine phosphorylation sites [(S/T)-P motif], designated P1-P4, on the pre-S protein of duck hepatitis B virus (DHBV) have been mutated. Mutants include single (P2, P3, P4) and double amino acid substitutions (P1 + P2, P3 + P4) and one with all four sites mutated (4P). Serine at position 118 (P3) was identified as the major site of phosphorylation by Western blotting and radioimmunoprecipitation after in vitro cell labeling with [35S]methionine or [33P]orthophosphate. Mutant virions generated by transfection of LMH cells were infectious both in vitro in duck hepatocyte primary cultures and in vivo in Pekin ducks. Intracellular relaxed circular (RC) and covalently closed circular (ccc) DNA syntheses were not affected by the P3 mutation or even the quadruple mutant. Extracellular virus production was slightly increased when the P3 site was mutated. CsCl gradient centrifugation showed no clear difference between mutant and wild-type virus with respect to the ratios of enveloped virus and nucleocapsid particles in hepatocyte culture supernatants. Trypsin or V8 protease digestion with or without NP-40 indicated that phosphorylation of the pre-S domain is not involved in determining the transmembrane topology of DHBV large protein. This phenotypic analysis indicates that DHBV pre-S phosphorylation has no apparent effect on DHBV replication and formation of mature viral particles in duck hepatocyte primary culture and does not affect infectivity in ducklings.

Amino Acid Sequence↗
PubMed1998

Impact of hepatitis G virus co-infection on the course of hepatitis C virus infection before and after liver transplantation.

BACKGROUND/AIMS: Hepatitis G virus (HGV), a new RNA virus that is parenterally transmitted, has frequently been found in patients with chronic hepatitis C (HCV) infection but its role in chronic liver disease is unknown. The purpose of this study was to determine the prevalence of HGV infection in transplantation patients infected with hepatitis C and to assess the impact of HGV co-infection on the course of HCV infection after liver transplantation. METHODS: Eighty-nine liver transplantation recipients with persistent hepatitis C viremia detected by polymerase chain reaction (PCR) were evaluated. Serum samples were tested before and after liver transplantation for HGV RNA by two different PCR methods: LC assay (Abbott Laboratories) and an RT-PCR procedure which we developed using the silica gel technique for extraction of the HGV RNA. E2 antibodies were detected before orthotopic liver transplantation by an EIA-test. HCV RNA was quantified by branched DNA assay, and HCV genotype was determined. A mean of nine liver biopsy specimens were examined for each patient and the severity of the lesions was compared in HCV-positive patients with or without HGV co-infection. RESULTS: The concordance between the two HGV RNA detection methods was excellent and the reproducibility of our RT-PCR procedure was confirmed. The prevalence of pretransplantation and posttransplantation HGV infection was 11% and 19%, respectively. Pretransplantation HGV infection was positively correlated with posttransplantation HGV infection (p<0.001). Before transplantation the E2 antibodies seroprevalence was 34%. Seven patients became HGV RNA positive after transplantation, but all of them were negative for E2 antibodies. Among the patients who remained RNA negative after liver transplantation, 40% were positive for E2 antibodies (p=0.04). Pretransplantation clinical features (except AST mean value) were not different in patients with HCV and HGV co-infection and those with HCV only. After a mean follow-up of 34 months (range: 6 to 70), 67/89 (75%) patients developed histological features of recurrent hepatitis but the frequency of the occurrence of graft hepatitis was not different between HGV/HCV co-infected patients and those with HCV alone (p=0.89). The mean interval from orthotopic liver transplantation to recurrence was 12.2 months (range: 3-63), which was not different for HVG/HVC-co-infected patients and HCV-infected patients. The histological severity of posttransplantation liver disease, and the graft and patient survival were not different for patients with and without HGV co-infection. CONCLUSIONS: Our results suggest the general persistence of HGV infection after liver transplantation, but HGV co-infection did not appear to influence the posttransplantation course of HCV infection. Before transplantation the prevalence of E2 antibodies was 34%, and our data clearly indicate that E2 antibodies were protective against HGV infection.

Adult↗
PubMed1998

Diagnostic value and tolerance of Lipiodol-computed tomography for the detection of small hepatocellular carcinoma: correlation with pathologic examination of explanted livers.

BACKGROUND/AIMS: This study aimed to assess the tolerance and the real sensitivity of Lipiodol-computed tomography in the detection of small hepatocellular carcinoma by comparison with pathological examination of the explanted livers. METHODS: Seventy-two patients with cirrhosis (Child A=8, B=36, C=28) awaiting orthotopic liver transplantation underwent Lipiodol-computed tomography to determine the presence, number and location of possible hepatocellular carcinoma nodules. Before liver transplantation six patients had a presumed single hepatocellular carcinoma diagnosed by biopsy. Liver transplantation was performed a mean of 6 months after Lipiodol-computed tomography. Explanted livers were sectioned at 0.8- to 1-cm intervals. Lipiodol-computed tomography staging and pathologic findings were compared. RESULTS: Pathologic studies showed 24 hepatocellular carcinoma nodules (diameter, 2-42 mm) not diagnosed before liver transplantation in 14 of the 72 livers. Lipiodol-computed tomography detected 6 of these 24 nodules, but none of the daughter lesions (n=9) in the six patients with a presumed single hepatocellular carcinoma. Lesion-by-lesion analysis revealed a sensitivity of 37%. Lipiodol-computed tomography falsely detected three additional nodules not confirmed by pathologic examination (1 haemangioma, 2 nondysplastic regenerating nodules). One Child C patient developed variceal bleeding within 2 days after injection of Lipiodol. CONCLUSIONS: Tolerance of this procedure was satisfactory, even in Child C patients. Lipiodol-computed tomography has a low sensitivity in the detection of small hapatocellular carcinoma. These results must be considered when liver resection or liver transplantation is proposed for the treatment of hepatocellular carcinoma.

Adult↗
PubMed1998

-Vaccination against hepatitis B-.

Although relatively uncommon among French children, hepatitis B virus infection is a major problem of public health which deserves coordinated strategies of prevention and immunization, in order to eliminate chronic carriers among groups at risk. The participation of pediatricians to these strategies is essential, knowing that transmission of hepatitis B virus from asymptomatic carrier mothers to their newborns contributes to new generation of chronic carriers who will be exposed to cirrhosis and hepatocellular carcinoma. Four hepatitis B vaccine are presently available in France with equal good efficiency and tolerance. These vaccines allow a protection against hepatitis B in 90 to 95% of the vaccinated subjects. Active search for new vaccines, particularly DNA vaccines, is in progress to extend the protection to the 5-10% non or low responders. The current recommended strategy of immunization in France associates immunizations of infants, preadolescents and groups at risk. In addition newborns from carrier mothers must receive combined passive and active immunization at birth.

Adolescent↗
PubMed1998

[National study of screening practices for hepatitis C among hemodialysis patients. Hepatitis Group].

French and American consensus conferences on hepatitis C confirmed the burden of that disease, especially in high risk populations. In France, the seroprevalence of HCV is about 20% among haemodialysed patients. This study aimed at describing the French screening practices in haemodialysed patients. In 1995, 1213 self-administered questionnaires were sent to nephrologists working in 715 dialysis units. The response rate was 48% (585/1213) and 485 questionnaires were analysed. In 98% of questionnaires nephrologists answered that they prescribed screening test. Routine screening with alanine amino-transferase (ALT) was reported in 98% of questionnaires, usually once a month (57%) or four times a year (23%). Routine anti-HCV serology was reported by 96%, usually once (28%) or twice (46%) a year. The two main annual strategies combining ALT and anti-HCV serology were 12 ALT and 2 serologies (21%), or 12 ALT and 1 serology (14%) per year. HCV RNA detection was reported mainly in the case of positive anti-HCV serology (70%). The study suggested heterogeneity in screening practices and revealed the need to determine the cost-effectiveness ratios of the various strategies.

Adult↗