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P Opolon

Publications and source records attributed to P Opolon.

At least 55 records · Page 3Linked to original sources
PubMed2000

Blood neutrophil functions and cytokine release in severe alcoholic hepatitis: effect of corticosteroids.

BACKGROUND/AIMS: Several observations point to an important role of interactions between polymorphonuclear neutrophils and cytokines in severe alcoholic hepatitis. The polymorphonuclear neutrophil activation status and the local and systemic pro- and anti-inflammatory cytokine responses were quantified. The effect of corticosteroids, widely used in this setting, was evaluated using these parameters. METHODS: We studied blood polymorphonuclear neutrophil functions in terms of L-selectin and beta2-integrin expression, H2O2 production and IL-8 and tumor necrosis factor alpha synthesis capacity. We also measured IL-8, tumor necrosis factor alpha and IL-10 plasma and liver tissue levels. Fifteen patients with alcoholic hepatitis were compared to 15 patients with alcoholic cirrhosis without alcoholic hepatitis, and to 10 healthy volunteers. The impact of a 28-day course of corticosteroids on blood neutrophils activation status and cytokine levels was evaluated in patients with alcoholic hepatitis. RESULTS: Blood polymorphonuclear neutrophils were activated, as shown by increased H2O2 production (48+/-6 vs 29+/-6 MFI in healthy controls), and decreased L-selectin expression (300+/-61 vs 449+/-59 in healthy controls). Upon stimulation, polymorphonuclear neutrophils synthesized large amounts of IL-8 (21.7+/-9.2 ng/ml vs 8.8+/-10 ng/ml in healthy controls) and tumor necrosis factor alpha (524+/-132 pg/ml vs 79+/-144 pg/ml in healthy controls). Tumor necrosis factor alpha and IL-8 plasma and tissue levels were markedly increased as IL-10 was barely detectable in alcoholic hepatitis patients, compared to cirrhotic patients and healthy controls. During steroid therapy, plasma levels of the pro-inflammatory cytokine IL-8 fell as early as day 14, while levels of the anti-inflammatory cytokine IL-10 increased on day 21. Finally, polymorphonuclear neutrophil functions returned to normal after treatment. CONCLUSION: Severe alcoholic hepatitis appears to be associated with polymorphonuclear neutrophil activation and an imbalance between pro- and anti-inflammatory cytokines; during steroid therapy a normalization of these parameters was observed.

Adrenal Cortex Hormones↗
PubMed2000

Replication status and histological features of patients with triple (B, C, D) and dual (B, C) hepatic infections.

In patients with multiple hepatotropic viral infections (B and C, or B, C and D), the reciprocal influence of each virus remains controversial. The aims of this study were twofold: first, to determine the impact of multiple infection on the replication status of B, C and D viruses and on histological features; and second, to compare patients with multiple infection to patients infected only with the hepatitis C virus (HCV). We retrospectively included 50 patients with multiple infection and 50 control HCV patients, who were matched on independent factors associated with fibrosis, such as age, gender, alcohol consumption and duration of infection. The replication status of hepatitis B virus (HBV), HCV and hepatitis D virus (HDV), and histological lesions, were determined. In patients with multiple infection, HCV RNA was present less frequently (44% vs 98%, P < 0.001) and the prevalence of cirrhosis was higher (35% vs 8%, P < 0.001). Among patients with triple infection (n = 16), HBV replication was observed in 25%, HCV RNA was detectable in only two (P < 0.0001) and HCV viremia was significantly lower than in the matched HCV patients (0 vs 54.7, P < 0.0001). Among patients with dual infection (n = 34), HCV RNA was present less frequently in those with serological markers of active HBV infection than in those without (30% vs 79%, P = 0.01). Hence, multiple infection is associated with a decrease of HCV replication. Cirrhosis seems to be more frequently observed in patients with multiple infection. In patients with triple infection, serum HCV RNA and markers of HBV replication were absent in 80%, suggesting that HDV acts as a dominant virus. In patients with dual infection, HBV and HCV exert an alternative, dominant replication.

Adult↗
PubMed2000

Natural history of HCV infection.

Chronic hepatitis C virus (HCV) infection affects 170 million individuals worldwide. These individuals are at risk of developing both hepatological and non-hepatological manifestations. HCV is usually only fatal when it leads to cirrhosis, the final stage of liver fibrosis. Therefore, an estimate of fibrosis progression represents an important surrogate end-point for the evaluation of the vulnerability of an individual patient. In untreated patients, the median expected time to cirrhosis is 30 years; 33% of patients have an expected median time to cirrhosis of less than 20 years and 31% will only progress to cirrhosis after more than 50 years, if ever. Several factors are associated with fibrosis progression rate: duration of infection, age, male gender, consumption of alcohol, HIV co-infection and low CD4 count. Non-hepatological manifestations are frequent with more than 70% of HCV patients experiencing fatigue or at least one extrahepatic clinical manifestation involving primarily the joints, skin and muscles. Several immunological abnormalities are frequently observed, including cryoglobulins (40%),anti-nuclear antibodies (10%) and anti-smooth muscle antibodies (7%). In contrast severe extrahepatic manifestations are rare, with 1% for systemic vasculitis.

Antibodies, Antinuclear↗
PubMed2000

Hepatitis virus infections in heart transplant recipients: epidemiology, natural history, characteristics, and impact on survival.

BACKGROUND & AIMS: We have observed a high prevalence of hepatitis B virus (HBV) and hepatitis C virus (HCV) infection in heart transplant recipients (HTRs). The aim of this study was to assess the epidemiology, natural history, and clinical and biological characteristics of viral hepatitis in HTRs. METHODS: From 1983 to 1992, 874 patients underwent heart transplantation at the Pitié-Salpêtrière Hospital, Paris, France, 459 of whom qualified for analysis. A total of 140 patients had posttransplantation hepatitis B, C, or non-A-E. Sixty-nine patients developed HBV infection, 49 HCV infection, 11 HBV-HCV coinfection, and 11 non-A-E hepatitis. RESULTS: HBV was transmitted nosocomially from patient to patient, most likely during endomyocardial biopsies. HCV was mainly transmitted through blood transfusions or the transplanted organ. Clinical and biological findings after 2 years of follow-up showed that 3 patients with an HBV genotype A precore mutant had severe or subfulminant hepatitis and that patients with HBV and HCV infection always progressed to chronicity. In general, patients had mild alanine aminotransferase level increases, a high level of viral replication, and few severe histologic lesions, except for patients infected by precore HBV mutants. Patients coinfected by HBV and HCV tended to have more severe liver lesions. The survival rate 5 years after transplantation in patients with viral hepatitis (HBV, 81%; HCV, 89%; HBV and HCV coinfection, 100%; non-A-E hepatitis, 73%) was similar to that in patients without liver test abnormalities (76%). The actuarial survival curve was also similar in patients with or without liver test abnormalities. CONCLUSIONS: In our experience, histologic liver lesions do not progress rapidly in patients with post-heart transplant infection caused by HBV or HCV. HBV or HCV infection seems to have little impact on the 5-year survival rate of HTRs.

Adolescent↗
PubMed2000

Fibrosis in patients with chronic hepatitis C: detection and significance.

Estimates of the extent of hepatic fibrosis and the rate of fibrosis progression represent important surrogate end points for evaluation of the vulnerability of an individual patient and for assessment of the impact of treatment on natural history in chronic hepatitis C. Using the median fibrosis progression rate, the median expected time to cirrhosis in untreated patients is around 30 years. However, one third of patients have an expected median time to cirrhosis of less than 20 years and one third will only progress to cirrhosis in more than 50 years, if ever. Factors independently associated with fibrosis progression are duration of infection, age, male gender, consumption of alcohol, human immunodeficiency virus co-infection, and low CD4 count. Evaluation of fibrosis progression is useful to decide treatment. Among patients with sustained viral response, fibrosis regresses. Evaluation of fibrosis progression has permitted validation of the concept of suppressive therapy. Among patients without viral clearance, interferon alone or in combination with ribavirin significantly reduces fibrosis progression rate in comparison with progression before treatment and to control groups. There is a major need for noninvasive markers of liver fibrosis. None are clearly useful today for the diagnosis of early stages of fibrosis.

Antiviral Agents↗
PubMed2000

Transforming growth factor beta 1 stimulates expression of the Epstein-Barr virus BZLF1 immediate-early gene product ZEBRA by an indirect mechanism which requires the MAPK kinase pathway.

Disruption of Epstein-Barr virus (EBV) latency is mediated by ZEBRA, the protein product of the immediate-early EBV gene, BZLF1. In vitro, phorbol 12-myristate 13-acetate (PMA), a potent activator of protein kinase C (PKC), induces reactivation of EBV. However, the physiological stimuli responsible for the disruption of viral latency are not well characterized. Transforming growth factor beta 1 (TGF-beta1) has also been shown to trigger the reactivation of EBV in Burkitt lymphoma cell lines; however, the effect of TGF-beta1 on ZEBRA expression has not been reported. To further understand this phenomenon, we have investigated the effect of TGF-beta1 on ZEBRA expression. Our results indicate that the treatment of different EBV-positive Burkitt's lymphoma cell lines with TGF-beta1 induces a time-dependent activation of BZLF1 transcription with a corresponding increase in the production of the protein ZEBRA. TGF-beta1 has been shown to exert its effects through a wide range of intracellular routes; in the present study, we have explored these pathways. Transient expression of Smad proteins on their own had no effect on ZEBRA expression. A specific inhibitor of p38 mitogen-activated protein kinase (MAPK), SB203580, did not affect TGF-beta1-induced ZEBRA expression, whereas treatment with the MAPK/ERK kinase inhibitors, PD98059 and U0126, dramatically decreased this induction. This suggests that TGF-beta1 effect on BZLF1 expression requires the MAPK pathway. However, in Raji and B95-8 cells additional routes can be used, as (i) the inhibition of ZEBRA induction by PD98059 or U0126 was incomplete, whereas these inhibitors completely abolished PMA-induced ZEBRA expression, (ii) TGF-beta1 induction of ZEBRA expression occurs in PKC-depleted cells, (iii) in Raji and in B95-8 cells, the effect of TGF-beta1 and PMA are additive. Transient transfection of the EBV-negative B-cell line DG75 with a BZLF1 promoter-fusion construct (Zp-CAT) showed that under conditions where the BZLF1 promoter is activated by PMA treatment, TGF-beta1 had no significant effect on the expression of the chloramphenicol acetyltransferase gene. Furthermore, TGF-beta1 induction of BZLF1 transcripts is dependent on de novo protein synthesis, which suggests that TGF-beta1 induces BZLF1 expression by an indirect mechanism.

Butadienes↗
PubMed1999

Systemic delivery of antiangiogenic adenovirus AdmATF induces liver resistance to metastasis and prolongs survival of mice.

Systemic administration of Ad5-based recombinant adenovirus leads to preferential transduction of the liver. Using this property, we have assessed the potential of venous viral injection to deliver a recombinant antiangiogenic adenovirus to treat cancer dissemination and improve survival. The results demonstrate that venous injection of adenovirus AdmATF, which encodes a secretable mouse ATF (amino-terminal fragment of urokinase) known to inhibit angiogenesis, suppressed angiogenesis induced by colon cancer metastasis growth in mice liver and improved survival. Nude mice were injected intravenously with 5 X 10(9) PFU of AdmATF and subsequently challenged after a 3-day interval by intrasplenically injected human colon carcinoma cells (LS174T, 3 x 10(6)) that home to liver. Microscopic inspection revealed that, within the AdmATF-pretreated mice (n = 8), the size and number of liver-metastasized nodules on day 30 were remarkably reduced (80% in number, p < 0.05) compared with control mice (n = 7) pretreated in parallel with a control adenovirus. Metastatic growth-related liver weight gain was also inhibited up to 90%. AdmATF-specific capability that offers liver resistance to the apparition and growth of liver metastasis was shown to correlate with the inhibition of peritumoral and intratumoral angiogenesis (reduced by 79%, p < 0.01 as shown by anti-vWF immunostaining of liver sections) and a twofold increase in tumor necrotic area and an eightfold increase in apoptotic tumor cell number. This protective effect was still observed when the mice were challenged 10 days after venous AdmATF injection (visible metastasis nodules: 6.3+/-3.1, n = 7 for control mice versus 2.7+/-2.9, n = 10 for treated mice, p < 0.05). More importantly, the mean survival has been prolonged from 45.1 days (n = 9) to 83.3 days (n = 10, p < 0.05). Altogether, the high efficacy, although transient, in this experimental mice model strongly advocates the plausibility of transforming the liver into a dissemination resistant organ by antiangiogenic gene therapy through systemic delivery approach.

Adenoviridae↗
PubMed1999

Nitric oxide mediation of active immunosuppression associated with graft-versus-host reaction.

In the immunosuppression accompanying the lethal systemic graft-versus-host reaction (GVHR) directed against minor histocompatibility antigens in irradiated adult mice, we previously determined that non-T, non-B, L-leucine methyl ester (LME)-sensitive cells were implicated via two different mechanisms: one, which is interferon-gamma (IFN-gamma)-dependent and affects both T-cell proliferative responses and thymus-independent antibody production by CD5(+) B cells; and a second, which is IFN-gamma-independent and affects B-cell proliferative responses. Because IFN-gamma induces the production of nitric oxide (NO), a potent immunosuppressive molecule, we investigated the involvement of NO in the suppression mediated by the LME-sensitive cells. Inducible NO synthase (iNOS) mRNA, iNOS protein, and the stable end products of iNOS pathway, L-citrulline and nitrite, were detected early in GVHR in LME-sensitive spleen cells taken ex vivo and could be amplified in vitro by T and B mitogens. Inhibition of NO production with arginine analogs (aminoguanidine, N(G)-monomethyl-L-arginine [LMMA]), like anti-IFN-gamma antibodies, reversed suppression of both T-cell responses to concanavalin A and CD5(+) B-cell responses, but not of B-cell response to lipopolysaccharides (LPS). The GVHR-associated, IFN-gamma-dependent immunosuppression of T-cell proliferation and of antibody synthesis by CD5(+) B cells is the consequence of NO production by LME-sensitive cells. Immunohistochemical analyses indicate that these cells belong to the macrophage lineage.

Animals↗
PubMed1999

Extrahepatic manifestations of chronic hepatitis C. MULTIVIRC Group. Multidepartment Virus C.

OBJECTIVE: To assess the prevalence of clinical and biologic extrahepatic manifestations of hepatitis C virus (HCV) infection and to identify associations between clinical and biologic manifestations. METHODS: To analyze the natural history of extrahepatic manifestations of HCV infection, we reviewed only the data recorded prospectively during the first visit of 1,614 patients with chronic HCV infection, coming from a single monocenter cohort. Exclusion criteria were positivity for hepatitis B surface antigen or human immunodeficiency virus. The prevalence of dermatologic, rheumatologic, neurologic, and nephrologic manifestations; diabetes; arterial hypertension; autoantibodies; and cryoglobulins were assessed. Then, using multivariate analysis, we identified demographic, biochemical, immunologic, virologic, and liver histologic factors associated with the presence of extrahepatic manifestations. RESULTS: At least 1 clinical extrahepatic manifestation was observed in each of 1,202 patients (74%). Five manifestations had a prevalence >10%: arthralgia (23%), paresthesia (17%), myalgia (15%), pruritus (15%), and sicca syndrome (11%). Four biologic abnormalities had a prevalence >5%: cryoglobulins (40%), antinuclear antibodies (10%), low thyroxine level (10%), and anti-smooth muscle antibodies (7%). Only vasculitis, arterial hypertension, purpura, lichen planus, arthralgia, and low thyroxine level were associated with cryoglobulin positivity. By univariate and multivariate analyses, the most frequent risk factors for the presence of clinical and biologic extrahepatic manifestations were age, female sex, and extensive liver fibrosis. CONCLUSION: Extrahepatic clinical manifestations are frequently observed in HCV patients and involve primarily the joints, muscles, and skin. The most frequent immunologic abnormalities include mixed cryoglobulins, antinuclear antibodies, and anti-smooth muscle antibodies. The most frequent risk factors for the presence of clinical and biologic extrahepatic manifestations are advanced age, female sex, and extensive liver fibrosis.

Adult↗
PubMed1999

Impact of hepatitis B and C virus on kidney transplantation outcome.

The impact of hepatitis B (HBV) and C (HCV) on patient survival after kidney transplantation is controversial. The aims of this study were (1) to assess the independent prognostic values of HBsAg and anti-HCV in a large renal transplant population, (2) to compare infected patients with noninfected patients matched for factors possibly associated with graft and patient survival, and (3) to assess the prognostic value of biopsy-proven cirrhosis. Eight hundred thirty-four transplanted patients were included: 128 with positive HBsAg (group I), 216 with positive anti-HCV (group II), and 490 without serological markers of HBV and HCV (group III). Fifteen percent and 29% of patients were HBsAg-positive and anti-HCV-positive, respectively. Ten-year survivals of group I (55 +/- 6%) and group II (65 +/- 5%) were significantly lower than survival of group III (80 +/- 3%, P <.001). At 10 years, among overall patients with HCV screening (n = 834), four variables had independent prognostic values in patient survival: age at transplantation (P <.0001), year of transplantation (P =.02), biopsy-proven cirrhosis (P =.03), and presence of HCV antibodies (P =.02). In the case control study, comparison of infected patients with their matched control patients showed that age at transplantation (P <.05), HBsAg (P =.005), and anti-HCV (P =.005) were independent prognostic factors. HCV, biopsy-proven cirrhosis, and age are independent prognostic factors of 10-year survival in patients with kidney grafts. The case-control study showed that anti-HCV and HBsAg were independently associated with patient and graft survivals. In infected patients, a routine liver histological analysis would improve selection of patients for renal transplantation.

Adult↗
PubMed1999

Antibiotic prophylaxis for the prevention of bacterial infections in cirrhotic patients with gastrointestinal bleeding: a meta-analysis.

In cirrhotic patients with gastrointestinal bleeding, antibiotic prophylaxis decreases the incidence of infections but most randomized trials have not shown an increase in survival. The aim of this meta-analysis was to assess the efficacy of antibiotic prophylaxis in the prevention of infections and its effect on survival rate in cirrhotic patients with gastrointestinal bleeding. Four end points were assessed: infection, bacteremia and/or spontaneous bacterial peritonitis (SBP), incidence of SBP, and death. For each end point, heterogeneity and treatment efficacy were assessed by Der Simonian and Peto methods. Five trials including 534 patients, 264 treated with antibiotic prophylaxis for 4 to 10 days and 270 without, were identified. Mean follow-up was 12 days. Antibiotic prophylaxis significantly increased the mean percentage of patients free of infection (32% mean improvement rate, 95% confidence interval [CI]: 22-42, P <.001), bacteremia and/or SBP (19% mean improvement rate, 95% CI: 11-26, P <.001), and SBP (7% mean improvement rate, 95% CI: 2.1-12.6, P =.006). Antibiotic prophylaxis also significantly increased the mean survival rate (9. 1% mean improvement rate, 95 % CI: 2.9-15.3, P =.004), without significant heterogeneity. In cirrhotic patients with gastrointestinal bleeding, short-term antibiotic prophylaxis significantly increases the mean percentage of patients free of infection and significantly increases short-term survival rate.

Antibiotic Prophylaxis↗
PubMed1999

Three cases of severe subfulminant hepatitis in heart-transplanted patients after nosocomial transmission of a mutant hepatitis B virus.

Fulminant and severe viral hepatitis are frequently associated with mutant hepatitis B virus (HBV) strains. In this study, the genetic background of a viral strain causing severe subfulminant outcome in heart-transplanted patients was studied and compared with viral hepatitis B strains that were not linked to severe liver disease in the same setting. A total of 46 patients infected nosocomially with HBV genotype A were studied. Five different viral strains were detected, infecting 3, 9, 5, 24, and 5 patients, respectively. Only one viral strain was found to be associated with the subfulminant outcome and 3 patient deaths as a consequence of severe liver disease. The remaining 43 patients with posttransplantation HBV infection did not show this fatal outcome. Instead, symptoms of hepatitis were generally mild or clinically undiagnosed. Comparison of this virus genome with the four other strains showed an accumulation of mutations in the basic core promoter, a region that influences viral replication, but also in hepatitis B X protein (HBX) (7 mutant motifs), core (10 mutant motifs), the preS1 region (5 mutant motifs), and the HBpolymerase open reading frame (17 motifs). Some of these variations, such as those in the core region, were located on the tip of the protruding spike of the viral capsid (codons 60 to 90), also known in part as an important HLA class II-restricted epitope region. These mutations might therefore influence the immune-mediated response. The viral strain causing subfulminant hepatitis was, in addition, the only strain with a preCore stop codon mutation and, thus, hepatitis B e antigen (HBeAg) expression was never observed. The combination of these specific viral factors is thought to be responsible for the fatal outcome in these immune-suppressed heart-transplant recipients.

Base Sequence↗
PubMed1999

Treatment of hepatitis C virus-related cirrhosis: a randomized, controlled trial of interferon alfa-2b versus no treatment.

To examine the effects of interferon (IFN) therapy on clinical, biochemical, and histological features in patients with compensated hepatitis C virus (HCV)-related cirrhosis, we have conducted a randomized, controlled trial of IFN therapy versus observation. Eight centers included a total of 99 patients with biopsy-proven cirrhosis. IFN-alpha2b, 3 million units three times per week, or no antiviral therapy was given for 48 weeks. Twenty-three patients dropped out. End-of-treatment biochemical response was not observed in any of the 39 controls but was observed in 6 of the 47 treated patients (P <.02); sustained biochemical response was obtained in only 2 treated patients. Controls and treated patients did not significantly differ with regard to the changes in serum level of albumin, bilirubin, alpha-fetoprotein, in plasma prothrombin, in histological activity, or liver collagen content. During trial or follow-up (160 +/- 57 weeks), hepatocellular carcinoma developed in 9 controls and 5 treated patients (NS); decompensation of cirrhosis occurred in 5 controls and 7 treated patients. Seven controls and 10 treated patients died. In conclusion, in patients with compensated HCV-related cirrhosis, a 48-week course of IFN therapy is safe and is able to induce end-of-treatment biochemical response in a significant proportion of patients. However, a 48-week course of IFN therapy usually fails to achieve sustained response and, within the limit of this study, did not significantly improve the 3-year outcome. Therefore, a longer course of IFN therapy or combination therapy with ribavirin should be evaluated in patients with HCV-related cirrhosis.

Adolescent↗
PubMed1999

Liver fibrosis progression in human immunodeficiency virus and hepatitis C virus coinfected patients. The Multivirc Group.

The natural history of hepatitis C virus (HCV) infection in human immunodeficiency virus (HIV)-infected patients has never been studied according to the concept of liver fibrosis progression. The aim of this work was to assess the fibrosis progression rate in HIV-HCV coinfected patients and in patients infected by HCV only. A cohort of 122 HIV-HCV coinfected patients was compared with a control group of 122 HIV-negative HCV-infected patients. Groups were matched according to age, sex, daily alcohol consumption, age at HCV infection, and duration and route of HCV infection. The fibrosis progression rate was defined as the ratio between fibrosis stage (METAVIR scoring system) and the HCV duration. The prevalence of extensive liver fibrosis (METAVIR fibrosis scores 2, 3, and 4) and moderate or severe activity were higher in HIV-infected patients (60% and 54%, respectively) than in control patients (47% and 30%, respectively; P <.05 and P <.001, respectively). The median fibrosis progression rate in coinfected patients and in control patients was 0.153 (95% confidence interval [CI], 0.117-0.181) and 0.106 (95% CI, 0.084-0.125) fibrosis units per year, respectively (P <.0001). HIV seropositivity (P <.0001), alcohol consumption (>50 g/d, P =.0002), age at HCV infection (<25 years old, P <.0001), and severe immunosuppression (CD4 count </=200 cells/microL, P <.0001) were associated with an increase in the fibrosis progression rate. In coinfected patients, alcohol consumption (>50 g/d), CD4 count (</=200 cells/microL), and age at HCV infection (<25 years old) (P <. 0001, respectively) were associated with a higher fibrosis progression rate. HIV seropositivity accelerates HCV-related liver fibrosis progression. In coinfected patients, a low CD4 count, alcohol consumption rate, and age at HCV infection are associated with a higher liver fibrosis progression rate.

Adult↗
PubMed1999

Long-term incidence of hepatitis B virus resistance to lamivudine in human immunodeficiency virus-infected patients.

Hepatitis B virus (HBV) resistance to lamivudine has not been extensively documented in human immunodeficiency virus (HIV)-infected patients. We studied the long-term incidence of HBV resistance to lamivudine in HIV-positive patients. Sixty-six HIV-HBV-coinfected patients were studied while receiving lamivudine (150 mg twice daily) as a part of antiretroviral therapy. All these patients had a detectable serum HBV DNA at the beginning of lamivudine therapy. Serum HBV DNA was quantified by molecular hybridization. Sequence analysis of the HBV polymerase was performed in patients who became resistant to lamivudine. After 2 months of lamivudine, HBV DNA became undetectable in 57 patients (86.4%, 95% CI: 75.7%-93.6%). After 2 years of lamivudine, 47% +/- 18.6% of the patients, had sustained HBV-DNA suppression. All the 22 tested patients with HBV resistance developed mutation at position 550 in the YMDD motif of the DNA polymerase. None of the following variables were associated with an increased risk of lamivudine resistance: age, associated protease inhibitor therapy, Center for Disease Control (CDC) stage C, known HIV-infection duration, serum HBV-DNA level at baseline, CD4 cell count and serum alanine transaminase levels at baseline and at HBV-replication suppression (2 months of lamivudine). Lamivudine (300 mg/d) is effective for the inhibition of HBV replication in HIV-infected patients. However, emergence of lamivudine-resistant HBV may occur in 20% of patients per year.

Adult↗
PubMed1999

Focal nodular hyperplasia of the liver on ferumoxides-enhanced MR imaging: features on conventional spin-echo, fast spin-echo and gradient-echo pulse sequences.

The aim of this study was to assess the efficacy of a superparamagnetic iron oxide, ferumoxides, in the detection and characterization of focal nodular hyperplasia (FNH) on MR conventional spin-echo (SE), fast spin-echo (FSE) and gradient-echo (GRE) images. Fourteen adults with 27 FNHs were evaluated at 1.5 T before and after injection of ferumoxides. T1-weighted and T2-weighted SE, T2-weighted FSE and T2(*)-weighted GRE sequences were used and analysed qualitatively and quantitatively. One hundred percent of FNHs showed a significant postcontrast decrease in signal intensity on T2- and T2*-weighted images. Heavily T2-weighted SE images showed the maximum decrease in FNH signal-to-noise ratio (S/N). Postcontrast GRE T2(*)-weighted images improved the detection of the central scar and the delineation of FNHs and demonstrated the best lesion-to-liver contrast-to-noise ratio (C/N). Postcontrast T1-weighted SE images showed the least lesion-to-liver C/N. Ferumoxides-enhanced MR imaging can help detect and characterize FNH. Conventional pre- and postcontrast T2-weighted SE images and postcontrast GRE T2*-weighted images should be used preferentially.

Adult↗
PubMed1999

Modeling the impact of interferon alfa treatment on liver fibrosis progression in chronic hepatitis C: a dynamic view. The Multivirc Group.

BACKGROUND & AIMS: Impact of hepatitis C treatment has never taken into account the dynamics of fibrosis progression. This study assessed the impact of interferon on liver fibrosis progression in patients with chronic hepatitis C according to 3-month aminotransferase activity response. METHODS: We recruited 287 patients, 185 treated and 102 control, with paired biopsy specimens. Before follow-up, the fibrosis progression rate per year was estimated as the ratio between fibrosis stage in METAVIR units (1 U, 1 stage; 4 U, cirrhosis) and the duration of infection. During follow-up, fibrosis progression was assessed by the observed difference between stages divided by duration between biopsies. RESULTS: The median fibrosis progression rate in treated patients decreased compared with the rate before treatment from 0.103 F METAVIR U/yr (95% confidence interval [CI], 0.087-0.120) to 0.000 (95% CI, 0.000-0.000; P </= 0.0001). Among 91 treated responders, fibrosis stage worsened in 19 (22%), compared with 21 (22%) of 94 treated nonresponders and 57 of 102 controls (56%; P </= 0.0001 compared with treated patients), and improved in 26 (29%), 17 (18%), and 8 (8%; P = 0.0002 compared with 29% and P = 0.03 compared with 18%), respectively. These observed differences persisted after genotype, viremia, sex, age at infection, duration of infection, and alcohol consumption were taken into account. CONCLUSIONS: Interferon treatment changes the natural fibrosis progression rate in patients with chronic hepatitis C independently of genotype and early response.

Adult↗