Search results for "virus replication"
showing 10 items of 199 documents
Hepatitis B virus maintains its pro-oncogenic properties in the case of occult HBV infection.
2003
Background & Aims: Occult hepatitis B virus (HBV) infection is characterized by persistence of HBV DNA into the tissue of hepatitis B surface antigen-negative individuals. The clinical relevance of this peculiar infection is still under debate. In particular, the impact of occult HBV infection in cases of hepatocellular carcinoma (HCC) is uncertain. We investigated the prevalence and molecular status of occult HBV in patients with HCC. Methods: We tested tumor tissues from 107 patients with HCC and the corresponding nontumor liver tissue from 72 of these patients for HBV DNA. We also examined liver specimens from 192 patients with chronic hepatitis. All cases were hepatitis B surface antige…
Hepatitis C virus replication in ‘autoimmune’ chronic hepatitis
1991
Abstract Both high and low anti-hepatitis C virus antibody (anti-HCV) prevalence has been reported in autoimmune chronic active hepatitis. Therefore, we studied 15 consecutive HBsAg-negative, ELISA anti-HCV-positive, autoantibody-positive patients with biopsy proven chronic active hepatitis in order to confirm ELISA specificity by immunoblot test (RIBA-HCV), and to evaluate HCV replication by serum HCV-RNA. Nine patients were anti-nuclear, three type 1 anti-liver-kidney microsomal and three anti-smooth muscle antibody positive. None had associated autoimmune disease. All cases showed mild clinical disease and only moderate necroinflammatory activity. Response to prednisone was poor. RIBA-HC…
Colonization of adrenal glands and ovaries of mice by HSV-2 variants
1990
HSV-2 strain ER was shown to consist of variants with different pathogenic phenotype: Variant ER+ replicates to high titers in the adrenal glands and the ovaries but much less in the spleen; the testes were not colonized. ER+ migrates to the spinal ganglia and is highly neuroinvasive after i.p. inoculation. Variant ER- replicates 100-1,000 fold less in the adrenal glands and the ovaries, but proceeds to the spinal ganglia without invading the CNS. However, both variants are highly neuropathogenic after direct i.c. injection. We conclude that neuropathogenicity, neuroinvasiveness and the ability to replicate in the adrenal glands as well as ovaries are each determined by different sets of ge…
Asthmatic bronchial epithelial cells have a deficient innate immune response to infection with rhinovirus
2005
Rhinoviruses are the major trigger of acute asthma exacerbations and asthmatic subjects are more susceptible to these infections. To investigate the underlying mechanisms of this increased susceptibility, we examined virus replication and innate responses to rhinovirus (RV)-16 infection of primary bronchial epithelial cells from asthmatic and healthy control subjects.Viral RNA expression and late virus release into supernatant was increased 50- and 7-fold, respectively in asthmatic cells compared with healthy controls. Virus infection induced late cell lysis in asthmatic cells but not in normal cells. Examination of the early cellular response to infection revealed impairment of virus induc…
Safety of etanercept and methotrexate in patients with rheumatoid arthritis and hepatitis C virus infection: a multicenter randomized clinical trial.
2014
Objective.To evaluate the safety and efficacy of therapy with etanercept and methotrexate (MTX) in patients with active rheumatoid arthritis (RA) and mild hepatitis C virus (HCV) infection.Methods.In this prospective open study, 29 patients with active RA were randomly assigned to receive therapy with MTX alone, etanercept alone, or a combination of MTX and etanercept, and monitored up to 54 weeks. The primary endpoint was safety; secondary aims were efficacy as defined by the 44-joint Disease Activity Score (DAS44) and health assessment questionnaire (HAQ). Serum liver enzymes and HCV viral load were serially measured.Results.In the whole cohort, aspartate aminotransferase (AST) serum leve…
Correlation of virus replication, cytokine (TNF-? and IL-1) producing cells, neuronal necrosis and inflammation after intranasal infection of mice wi…
1995
The number of TNF-alpha and IL-1 beta producing cells was investigated during the acute replication phase of herpes simplex virus (HSV) in trigeminal ganglia after intranasal infection with strains of different virulence. The highly virulent strain WAL replicated strongly and induced many cytokine producing cells early in the ganglia. The low virulent strain HFEM replicated less, only few cytokine producing cells were detected late. The thymidine-kinase negative (TK-) virus 1301 did not replicate but produced some lymphocytic inflammation. The higher the virulence of strains of HSV-1 or -2 was, the stronger was the extent of histopathological lesions; moreover, a dissociation in time betwee…
Transmissible gastroenteritis virus (TGEV)-based vectors with engineered murine tropism express the rotavirus VP7 protein and immunize mice against r…
2011
A coronavirus vector based on the genome of the porcine transmissible gastroenteritis virus (TGEV) expressing the rotavirus VP7 protein was constructed to immunize and protect against rotavirus infections in a murine model. The tropism of this TGEV-derived vector was modified by replacing the spike S protein with the homologous protein from mouse hepatitis virus (MHV). The rotavirus gene encoding the VP7 protein was cloned into the coronavirus cDNA. BALB/c and STAT1-deficient mice were inoculated with the recombinant viral vector rTGEVS-MHV-VP7, which replicates in the intestine and spreads to other organs such as liver, spleen and lungs. TGEV-specific antibodies were detected in all the in…
Significance of IgG and IgM HCV antibody secretion in vitro in patients with chronic hepatitis C: correlation with disease activity and response to i…
1994
Hepatitis C virus antibodies are found in the serum of most patients with chronic hepatitis C. However, the significance of the humoral response is still uncertain. In this study, in vitro IgG and IgM anti-hepatitis C virus secretion by peripheral blood mononuclear cells of patients with chronic hepatitis C was analyzed. Peripheral-blood mononuclear cells from 21 of 36 patients (58.3%) secreted IgG anti-hepatitis C virus in vitro, as demonstrated with anti-hepatitis C virus—specific enzyme immunoassays and recombinant immunoblot assays. Ten of the 36 patients (27.8%) showed both IgG and IgM anti-hepatitis C virus core in vitro. In 9 of these 10 patients, IgM anti-hepatitis C virus was also …
Mode of selection and experimental evolution of antiviral drugs resistance in vesicular stomatitis virus
2004
Abstract The possession of an antiviral resistance mutation benefits a virus when the corresponding antiviral is present. But does the resistant virus pay a fitness cost when the antiviral is absent? Would an evolutionary history of association between a genotype and a resistance mutation overcome this cost by changes compensating the harmful side-effect of resistance mutations? Are combined therapies more effective against the rise of resistant viruses or against evolutionary compensations? To explore all these questions, we took an experimental evolution approach. After selecting vesicular stomatitis virus (VSV) populations able to replicate under increasing concentrations of ribavirin an…
Chronic hepatitis B: who to treat and which choice of treatment?
2009
The goal of antiviral therapy in patients with chronic hepatitis B is to prevent, through persistent suppression of HBV replication, cirrhosis and hepatocellular carcinoma. Currently, seven drugs are available: IFN-alpha, pegylated interferon, lamivudine, adefovir dipivoxil, entecavir, telbivudine and tenofovir. The choice of the drugs should always take into consideration the clinical features of patients, the antiviral efficacy of each drug, the risk of developing resistance, the long-term safety profile, the method of administration and the cost of therapy. Ideal candidates for treatment are hepatitis B e antigen-positive patients with a prolonged phase of immune clearance and hepatitis …