Search results for "hepatitis C viru"
showing 10 items of 408 documents
Genetic Variability of Hepatitis C Virus before and after Combined Therapy of Interferon plus Ribavirin
2008
We present an analysis of the selective forces acting on two hepatitis C virus genome regions previously postulated to be involved in the viral response to combined antiviral therapy. One includes the three hypervariable regions in the envelope E2 glycoprotein, and the other encompasses the PKR binding domain and the V3 domain in the NS5A region. We used a cohort of 22 non-responder patients to combined therapy (interferon alpha-2a plus ribavirin) for which samples were obtained before initiation of therapy and after 6 or/and 12 months of treatment. A range of 25-100 clones per patient, genome region and time sample were sequenced. These were used to detect general patterns of adaptation, t…
Recombination in Hepatitis C Virus
2011
Hepatitis C virus (HCV) is a Flavivirus with a positive-sense, single-stranded RNA genome of about 9,600 nucleotides. It is a major cause of liver disease, infecting almost 200 million people all over the world. Similarly to most RNA viruses, HCV displays very high levels of genetic diversity which have been used to differentiate six major genotypes and about 80 subtypes. Although the different genotypes and subtypes share basic biological and pathogenic features they differ in clinical outcomes, response to treatment and epidemiology. The first HCV recombinant strain, in which different genome segments derived from parentals of different genotypes, was described in St. Petersburg (Russia) …
MHC class II genes influence the susceptibility to chronic active hepatitis C
1997
Chronic hepatitis C develops in more than 70% of hepatitis C virus infected subjects. Viral factors influence the disease course, but little is known about the importance of host factors.Frequencies of major histocompatibility complex (MHC) class I and class II antigens were analyzed in two groups of patients with chronic hepatitis C virus infection and in control subjects. MHC class I typing was done by standard microlymphocytotoxicity assays. DRB1 and DQA1 genotyping was done by PCR based typing methods.DRB1*0301 was found in 26 of 75 patients with chronic hepatitis C virus infection (34.7%) and in 12 of 101 control subjects (11.9%) (relative risk 3.9; p0.001). Homozygosity for this allel…
Evidence of Recombination in Intrapatient Populations of Hepatitis C Virus.
2008
Hepatitis C virus (HCV) is a major cause of liver disease worldwide and a potential cause of substantial morbidity and mortality in the future. HCV is characterized by a high level of genetic heterogeneity. Although homologous recombination has been demonstrated in many members of the family Flaviviridae, to which HCV belongs, there are only a few studies reporting recombination on natural populations of HCV, suggesting that these events are rare in vivo. Furthermore, these few studies have focused on recombination between different HCV genotypes/subtypes but there are no reports on the extent of intra-genotype or intra-subtype recombination between viral strains infecting the same patient.…
Reducing treatment duration in patients infected with hepatitis C genotype 1: any need for further studies?
2009
The recommended treatment duration with pegylated interferon-α plus ribavirin for patients infected with hepatitis C virus (HCV) genotype 1 is 48 weeks. Interestingly, a subpopulation of genotype 1 patients experience rapid decreases in HCV RNA levels once treatment is initiated and attain rapid virological response, defined as undetectable HCV RNA at week 4 of therapy. Several studies have shown that these patients can be effectively treated for a 24-week period without any significant decreases in sustained virological response rates. The aim of this review was to consider the existing clinical evidence regarding the use of a 24-week treatment schedule among genotype 1 patients and to hi…
Impact of hepatitis C virus infection on lifestyle
2007
AIM: To evaluate the impact of the diagnosis of hepatitis C infection on lifestyle habits such as smoking, drinking, sports activity and diet. METHODS: A self-administered, anonymous question-naire was offered to out-patients with HCV infection consecutively attending three clinical centres in Italy. RESULTS: Of the 275 respondents, 62.2% (171) were male. Mean age was 51 (range 20-80) years. Overall, after the diagnosis of hepatitis C, 74.5% of drinkers had modified (giving up or reducing) alcohol consumption, 21.3% of smokers had modified their habits and 32.3% of subjects who reported sports activity had either stopped or reduced frequency of activity or chose a less fatiguing sport. Sixt…
HCV-induced immune responses influence the development of operational tolerance after liver transplantation in humans.
2014
Pathogen-induced immune responses prevent the establishment of transplantation tolerance in experimental animal models. Whether this occurs in humans as well remains unclear. The development of operational tolerance in liver transplant recipients with chronic hepatitis C virus (HCV) infection allows us to address this question. We conducted a clinical trial of immunosuppression withdrawal in HCV-infected adult liver recipients to elucidate (i) the mechanisms through which allograft tolerance can be established in the presence of an ongoing inflammatory response and (ii) whether anti-HCV heterologous immune responses influence this phenomenon. Of 34 enrolled liver recipients, drug withdrawal…
12-month follow-up analysis of a multicenter, randomized, prospective trial in de novo liver transplant recipients (LIS2T) comparing cyclosporine mic…
2006
The LIS2T study was an open-label, multicenter study in which recipients of a primary liver transplant were randomized to cyclosporine microemulsion (CsA-ME) (Neoral) (n = 250) (monitoring of blood concentration at 2 hours postdose) C2 or tacrolimus (n = 245) (monitoring of trough drug blood level [predose]) C0 to compare efficacy and safety at 3 and 6 months and to evaluate patient status at 12 months. All patients received steroids with or without azathioprine. At 12 months, 85% of CsA-ME patients and 86% of tacrolimus patients survived with a functioning graft (P not significant). Efficacy was similar in deceased- and living-donor recipients. Significantly fewer hepatitis C–positive pati…
Hepatitis C virus re-infection: new perspectives
2006
Hepatitis C virus (HCV) re-infection of the liver graft has been recognized to be one of the most important factors that determines prognosis and outcome after liver transplantation in HCV-positive patients. Graft loss due to recurrent HCV re-cirrhosis and subsequent hepatic decompensation, which is the predominant cause of death among transplant recipients, reflects the prognostic significance of HCV re-infection. Despite better overall outcome after liver transplantation, the prognosis of HCV-infected patients has not improved during the last two decades. Recent data suggest that increased liver donor age and intensified immunosuppression of transplant patients are the most important cont…
Role of mTOR inhibitors for the control of viral infection in solid organ transplant recipients
2016
Appropriate post-transplant immunosuppressive regimens that avoid acute rejection, while reducing risk of viral reactivation, have been sought, but remain a chimera. Recent evidence suggesting potential regulatory and antiviral effects of mammalian target of rapamycin inhibitors (mTORi) is of great interest. Although the concept of an immunosuppressive drug with antiviral properties is not new, little effort has been made to put the evidence together to assess the management of immunosuppressive therapy in the presence of a viral infection. This review was developed to gather the evidence on antiviral activity of the mTORi against the viruses that most commonly reactivate in adult solid org…