Prevalence and impact of occult hepatitis B infection in chronic hepatitis C patients treated with pegylated interferon and ribavirin.

The prevalence of occult hepatitis B, defined by absence of HBsAg and HBV DNA, ranges widely in patients with hepatitis C. This may influence the treatment of hepatitis C and the severity of liver disease. Sensitive and specific real-time PCR techniques are available commercially and can detect more reliably low HBV DNA levels.

Inhibition of Epstein-Barr virus replication by small interfering RNA targeting the Epstein-Barr virus protease gene.

Background: The Epstein-Barr virus (EBV) protease (PR), coded by the BVRF2 gene, is essential for the maturation of the viral capsid and viral DNA packaging during the late stage of the EBV lytic cycle. Like the other herpesvirus serine PRs, EBV PR could be a target for the inhibition of EBV replication. To date, no data have been reported on the inhibition of EBV PR messenger RNA (mRNA) by small interfering RNA (siRNA).

Assessment of selective real-time PCR for quantitation of lamivudine and adefovir hepatitis B virus-resistant strains and comparison with direct sequencing and line probe assays.

A selective real-time PCR (sPCR) assay has been developed to detect the rtM204V/I and rtN236T mutations of hepatitis B virus (HBV) associated with resistance to lamivudine and adefovir. Using mixtures of mutant and wild-type plasmids, this sPCR was able to detect 0.1% of mutated strain in a total plasmid population of 10(5) copies and was more sensitive in detecting resistant strains than the line probe INNO-LiPA-DR-v2 assay and a direct sequencing assay.

Sustained virological and biochemical responses to lamivudine and adefovir dipivoxil combination in a chronic hepatitis B infection despite mutations conferring resistance to both drugs.

Background: Sequential monotherapies of nucleotide analogs used in chronic hepatitis B treatment can lead to the selection of a resistance mutation to each antiviral drug.

Case Presentation: A patient with chronic hepatitis B was successively treated with lamivudine monotherapy, lamivudine-adefovir dual therapy, adefovir monotherapy and again with an adefovir-lamivudine dual therapy. Lamivudine-associated mutations (rtL180M and rtM204V/I) followed by adefovir-associated mutations (rtN236T and rtA181V) emerged during the two monotherapy regimens.

A prospective follow-up of Epstein-Barr virus LMP1 genotypes in saliva and blood during infectious mononucleosis.

To monitor multiple Epstein-Barr virus (EBV) infections during the early and convalescent stages of infectious mononucleosis (IM), a cloning and sequencing study of the LMP1 gene was conducted in saliva and peripheral blood mononuclear cells (PBMCs) from 23 patients with IM at day 0 (D0) and day 180 (D180) after the onset of the disease. Multiple EBV strains were detected in 9 (39%) of the patients during follow-up, with 7 of 9 cases detected as early as D0. Six of the nine patients harbored the same dominant strain in saliva and PBMCs during follow-up, with a trend toward a restriction of the number of EBV strains in saliva but not in PBMCs at D180.

Long-term shedding of infectious epstein-barr virus after infectious mononucleosis.

Epstein-Barr virus (EBV) DNA loads in peripheral blood mononuclear cells (PBMCs), plasma, and saliva, as well as infectivity of the virus in saliva, were evaluated in 20 patients for 6 months after the onset of infectious mononucleosis (IM). All patients displayed sustained high EBV DNA loads in the saliva, associated with a persistent infectivity of saliva at day 180. EBV DNA load in PBMCs decreased significantly from day 0 to day 180 (in spite of a viral rebound between day 30 and day 90 in 90% of the patients), and EBV DNA rapidly disappeared from plasma.