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Dive into the research topics where Valérie Thiers is active.

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Featured researches published by Valérie Thiers.


Journal of Hepatology | 1992

Infection of peripheral mononuclear blood cells by hepatitis C virus

Anna Linda Zignego; Donatella Macchia; Monica Monti; Valérie Thiers; Marcello Mazzetti; Marco Foschi; Enrico Maggi; Sergio Romagnani; Paolo Gentilini; Christian Brechot

We investigated the infection of peripheral blood mononuclear cells (PBMNC) by hepatitis C virus (HCV) in 5 patients with HCV-related chronic hepatitis. The presence of HCV-RNA-positive and -negative strands was tested with the polymerase chain reaction (PCR) method. In all subjects, HCV-RNA was shown in PBMNC. In 3 cases, HCV-RNA was shown in the T- and B-cell populations, with viral RNA also present in the monocyte-macrophage fraction of two of these. HCV-RNA-negative stranded molecules, indicative of the viral multiplication, were significantly increased in cells maintained in cultures with PHA/PMA stimulation. The results indicate that HCV infect blood mononuclear cells, thus suggesting that this cellular tropism may play a role in HCV infection.


Journal of Hepatology | 1998

Retrospective analysis of the impact of HIV infection and alcohol use on chronic hepatitis C in a large cohort of drug users

Stanislas Pol; Barbara Lamorthe; Ngoc Trinh Thi; Valérie Thiers; Françoise Carnot; Hervé Zylberberg; Pierre Berthelot; Christian Bréchot; Bertrand Nalpas

BACKGROUND/AIM This retrospective study aimed to better define the respective biological and pathological impact of human immunodeficiency virus infection and chronic alcohol consumption on the course of hepatitis C virus infection in intravenous drug users. METHODS Two hundred and ten consecutive anti-HCV positive intravenous drug users, among whom 60 were also anti-HIV positive, took part in the study at the University Hospital, Paris, France. RESULTS The activity of aspartate aminotransferase and gamma-glutamyl transpeptidase was significantly increased in serum from anti-HIV positive patients. The mean hepatitis activity index was significantly higher in anti-HIV positive patients (p<0.05), among whom there was also a higher proportion of patients with cirrhosis as compared to anti-HIV negative patients (30.0 vs 15.3%, p<0.0001). Excessive alcohol drinking (recorded in around 35% of the patients, whatever their HIV status), as compared to non-excessive drinking, was more often associated with cirrhosis in anti-HIV negative (24.5 vs 11.3%, p<0.05) than in anti-HIV positive patients (30.4 vs 29.7%, not significant). In a multivariate analysis, HIV infection (relative risk 2.2, confidence interval 1.1-4.5) and excessive alcohol drinking (relative risk 1.9, confidence interval 1.0-3.9) were the variables independently associated with the risk of cirrhosis. CONCLUSION Human immunodeficiency virus infection worsens the course of chronic hepatitis C in intravenous drug users. Excessive alcohol drinking also appears to be a crucial negative cofactor, and therefore alcohol withdrawal should be proposed as an integral part of the therapy.


The Journal of Infectious Diseases | 1998

Absence of Hepatitis C Virus and Detection of Hepatitis G Virus/GB Virus C RNA Sequences in the Semen of Infected Men

Augusto E. Semprini; Tiziana Persico; Valérie Thiers; Monica Oneta; Rosella Tuveri; Paola Serafini; Antonio Boschini; Simonetta Giuntelli; Giorgio Pardi; Christian Bréchot

The identification of hepatitis C virus (HCV) in semen remains controversial and that of hepatitis G virus (HGV) or GB virus C (GBV-C) has never been investigated. Serum and semen from 90 anti-HCV-positive drug users were tested (27 infected with HIV) for HCV and HGV/GBV-C RNAs by polymerase chain reaction (PCR) assay, hybridization, and sequence analysis. Semen was processed into round cells, seminal plasma, and spermatozoa. Fifty-six patients were HCV-viremic, but HCV-RNA was not identified in their seminal fractions. However, PCR inhibitors were found in the semen of 34 of these men. Twenty-eight patients had HGV/GBV-C RNA in their blood and for 24 of them, ejaculates were available for analysis. HGV/GBV-C RNA was found in the seminal plasma of 6 of 12 samples free from PCR inhibitors. These results agree with the low risk of sexual transfer of HCV and provide preliminary evidence for the presence of HGV/GBV-C in semen.


Gastroenterology | 1988

Hepatitis B virus and hepatitis B-related viral infection in renal transplant recipients

F. Degos; C. Lugassy; Claude Degott; A. Debure; Françoise Carnot; Valérie Thiers; Pierre Tiollais; H. Kreis; Christian Brechot

Hepatitis B virus (HBV) infection may induce severe hepatitis and affect long-term survival of kidney transplant recipients. Persistent viral infection has been shown to occur despite the absence of usual serologic markers. The liver and serum HBV deoxyribonucleic acid (DNA) status of 90 patients were studied prospectively; recently transplanted patients, both hepatitis B virus surface antigen (HBsAg)-positive and negative, with and without liver disease, were investigated with HBV serology, serum HBV DNA, and liver histology. Thirty-four patients had detectable HBsAg, and 21 had viral multiplication at the time of transplantation. Serial HBV DNA determinations performed in 57 of 90 patients disclosed (a) reactivation of HBV replication in 11 of 12 HBsAg-positive patients, (b) increase of viral replication when positive on the initial sample in 6 of 11 patients, and (c) development of HBV replication in 7 of 35 of the HBsAg-negative patients. Moreover, liver HBV DNA studies showed a statistical correlation between the presence of integrated liver HBV DNA and chronic hepatitis in HBsAg-negative patients. This study demonstrates prospectively the significant association of HBsAg-positive as well as HBsAg-negative HBV infection with chronic hepatitis and suggests that immunosuppressive therapy may enhance the viral replication in both HBsAg-positive and negative subjects.


Archives of Virology | 1997

Hepatitis C virus infection in mixed cryoglobulinemia and B-cell non-Hodgkin’s lymphoma: evidence for a pathogenetic role

Anna Linda Zignego; Clodoveo Ferri; Carlo Giannini; L. La Civita; Grazia Careccia; G. Longombardo; G. Bellesi; F Caracciolo; Valérie Thiers; Paolo Gentilini

SummaryWe investigated the pathogenetic relevance of hepatitis C virus (HCV) infection in mixed cryoglobulinemia (MC) with or without complicating B-cell Non-Hodgkin’s lymphoma (NHL) in comparison with other immunological and lymphoproliferative disorders. The following groups of patients were studied: A) 25 patients with MC in 7 cases evolved into B-cell NHL; B) 25 healthy subjects; C) 22 patients with different systemic immune diseases; D) 24 patients with chronic HCV infection without MC; E) 25 patients with B-cell idiopathic NHL. Methods used included: i) Polymerase chain reaction (PCR) for HCV RNA detection in serum and peripheral blood mononuclear cells (PBMC) (uncultured or mitogen-stimulated); ii) Branched DNA (b-DNA) for HCV RNA quantification; iii) HCV genotyping by genotype-specific primers localized in the core region and by hybridization of amplification products of the 5′ untranslated region (5′UTR), obtained with universal primers, using genotype-specific probes. Serum anti-HCV and HCV RNA were detected in 88% and 73% of MC patients, respectively, and in a significantly lower percentage of healthy controls and patients with autoimmune diseases. HCV RNA concentration was significantly lower in supernatants than in corresponding whole sera (p<0.001). Plus-strand HCV RNA was detected in 81% of peripheral blood mononuclear cell (PBMC) samples and minus-strand in the majority of fresh or mitogen stimulated cells. All MC patients with NHL had HCV RNA sequences in PBMC. HCV genotype 2a/III was detected in MC patients with a prevalence that was significantly higher than in HCV infected patients without MC. Surprisingly, HCV markers (anti-HCV and/or HCV RNA) were found in 32% of patients with idiopathic NHL. These data suggest that HCV infection is involved in the pathogenesis of MC through both direct participation in the immune complex related vasculitis and by triggering the lymphoproliferative disorder underlying the disease. This latter disorder seems to be related to HCV lymphotropism which could also be responsible for the evolution of MC to malignant lymphoma. This study also suggests that HCV infection may be involved in the pathogenesis of idiopathic B-cell NHL through a similar pathogenetic mechanism.


Journal of Hepatology | 1992

Hepatitis C viremia and anti-HCV antibodies in alcoholics.

Bertrand Nalpas; Valérie Thiers; Stanislas Pol; Françoise Driss; Véronique Thépot; Pierre Berthelot; C. Brechot

We determined serum hepatitis C status using a RIBA2 kit and a sensitive PCR procedure in 62 chronic alcoholics, 36 of whom had anti-HCV antibodies (Ab) detectable in an ELISA1 assay. Anti-HCV antibodies were detected in 22 patients using RIBA2. HCV RNA was detected by means of PCR in 18 patients who were RIBA2 positive and in none who were RIBA2 negative. Liver biopsies, available for 12 HCV RNA-positive patients, revealed histological features of purely alcohol-related lesions in seven and mixed alcohol-viral lesions in five. These results indicate that HCV replication is maintained in most alcoholics who score positive for anti-HCV Ab in the RIBA2 test, and that HCV viremia can be associated with histological features typical of alcoholic liver disease.


Infection Control and Hospital Epidemiology | 2001

Hepatitis C in a ward for cystic fibrosis and diabetic patients: possible transmission by spring-loaded finger-stick devices for self-monitoring of capillary blood glucose.

Jean-Claude Desenclos; Martine Bourdiol-Razes; Bernard Rolin; Patrick Garandeau; Jacques Ducos; Christian Bréchot; Valérie Thiers

OBJECTIVE To identify the routes of transmission in a nosocomial outbreak of hepatitis C virus (HCV) infection. DESIGN Epidemiological investigation, including screening for HCV of hospitalized patients, and a retrospective cohort study, review of hygiene and medical practices, and molecular comparison of HCV isolates. SETTING A specialized care unit for cystic fibrosis (CF) and diabetic patients at an acute-care facility in the south of France. RESULTS Of the 57 CF patients (age in 1995: 2-28 years), 38 (66.7%) were tested and 22 (57.9%) were anti-HCV positive. Eight (50%) of 16 patients with anti-HCV antibody tested by polymerase chain reaction were viremic. No patients had received blood products or had any history of intravenous drug use. All 18 (100%) patients with CF who had ever undergone self-monitoring of capillary blood glucose in the unit were anti-HCV positive, compared to 4 (20%) of 20 who had not (relative risk, 5.0; 95% confidence interval, 2.1-12.0). Seventy (39.5%) of the patients with diabetes were screened for anti-HCV; 12 (18.8%) tested positive, with 3 (25%) positive for HCV-RNA. Patients with diabetes had routine capillary blood glucose monitoring while hospitalized and shared with CF patients the same spring-triggered devices for capillary blood glucose monitoring. The disposable platform of the devices was not changed between patient use. All HCV isolates belonged to the type 1, subtype b, and phylogenetic analysis showed a close homology by sequencing of NS5b and E2/HVR regions. CONCLUSION As reported earlier for the hepatitis B virus, shared spring-triggered devices for capillary blood glucose monitoring by finger puncture may transmit HCV. Strict application of Standard Precautions procedures is warranted in any healthcare setting.


Infection Control and Hospital Epidemiology | 2002

Outbreak of hepatitis C virus infection in a hemodialysis unit: potential transmission by the hemodialysis machine?

Elisabeth Delarocque-Astagneau; Nadège Baffoy; Valérie Thiers; Nicole Simon; Henriette de Valk; Syria Laperche; Anne-Marie Couroucé; Pascal Astagneau; Claude Buisson; Jean-Claude Desenclos

OBJECTIVE To identify the routes of transmission during an outbreak of infection with hepatitis C virus (HCV) genotype 2a/2c in a hemodialysis unit. DESIGN A matched case-control study was conducted to identify risk factors for HCV seroconversion. Direct observation and staff interviews were conducted to assess infection control practices. Molecular methods were used in a comparison of HCV infecting isolates from the case-patients and from patients infected with the 2a/2c genotype before admission to the unit. SETTING A hemodialysis unit treating an average of 90 patients. PATIENTS A case-patient was defined as a patient receiving hemodialysis with a seroconversion for HCV genotype 2a/2c between January 1994 and July 1997 who had received dialysis in the unit during the 3 months before the onset of disease. For each case-patient, 3 control-patients were randomly selected among all susceptible patients treated in the unit during the presumed contamination period of the case-patient. RESULTS HCV seroconversion was associated with the number of hemodialysis sessions undergone on a machine shared with (odds ratio [OR] per additional session, 1.3; 95% confidence interval [CI95], 0.9 to 1.8) or in the same room as (OR per additional session, 1.1; CI95, 1.0 to 1.2) a patient who was anti-HCV (genotype 2a/2c) positive. We observed several breaches in infection control procedures. Wetting of transducer protectors in the external pressure tubing sets with patient blood reflux was observed, leading to a potential contamination by blood of the pressure-sensing port of the machine, which is not accessible to routine disinfection. The molecular analysis of HCV infecting isolates identified among the case-patients revealed two groups of identical isolates similar to those of two patients infected before admission to the unit. CONCLUSIONS The results suggest patient-to-patient transmission of HCV by breaches in infection control practices and possible contamination of the machine. No additional cases have occurred since the reinforcement of infection control procedures and the use of a second transducer protector.


Transplantation | 2000

HBV genotypic resistance to lamivudine in kidney recipients and hemodialyzed patients.

Hélène Fontaine; Valérie Thiers; Yves Chretien; Hervé Zylberberg; R. Poupon; Christian Bréchot; Christophe Legendre; Henri Kreis; Stanislas Pol

BACKGROUND Lamivudine is a potent inhibitor of human immunodeficiency virus reverse transcriptase and hepatitis B virus (HBV) DNA polymerase. Its overall efficiency is clearly hampered by relapse at discontinuation and by risk of genotypic resistance. We describe herein the first cases of HBV resistance to lamivudine in kidney recipients and hemodialyzed patients. METHODS We analyzed 26 HBV-infected kidney recipients and five hemodialyzed patients treated with lamivudine who became serum HBV DNA-negative (by Digene test). The biological and virological follow-up identified breakthrough as defined by the reappearance of serum HBV DNA. In two cases of breakthrough, HBV DNA was amplified and sequenced through the polymerase domain, including the YMDD motif, before the beginning of treatment and at time of breakthrough to determine genotypic mutations. RESULTS Ten breakthroughs (reappearance of serum HBV DNA) were observed after a median follow-up of 11 months in eight kidney recipients and two hemodialyzed patients after a median duration of treatment of 16.5 (from 4 to 31) months of treatment. Previous HBe/anti-HBe seroconversion was not observed in the patients who escaped. In two kidney recipients, the comparison of HBV-DNA sequences before the treatment and after the breakthrough identified in one case a mutation of the highly conserved YMDD motif (YVDD), whereas in the second case, no genotypic mutation was observed in the sequenced region. CONCLUSION We report the first cases of HBV genotypic resistance to lamivudine in kidney recipients and hemodialysis patients. Genotypic resistance is observed after 4-31 months of therapy. The YMDD mutation does not account for all cases of virological escape.


Annals of Internal Medicine | 1990

Persistence of Hepatitis B Virus DNA Demonstrated by Polymerase Chain Reaction in Serum and Liver after Loss of HBsAg Induced by Antiviral Therapy

Patrick Marcellin; Michèle Martinot-Peignoux; Marie-Anne Loriot; Emile Giostra; Nathalie Boyer; Valérie Thiers; Jean-Pierre Benhamou

Excerpt The polymerase chain reaction is a method of amplification of nucleic acids (1) that allows the detection of a very small amount of hepatitis B virus DNA (HBV-DNA), not detected by usual sl...

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Stanislas Pol

Necker-Enfants Malades Hospital

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Didier Samuel

Université Paris-Saclay

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Hervé Zylberberg

Necker-Enfants Malades Hospital

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