Secondary structure of DNA released from purified capsids of human parvovirus B19 under moderate denaturing conditions.

Parvovirus B19 (B19V) possesses a linear single-stranded DNA genome of either positive or negative polarity. Due to intramolecular sequence homologies, either strand may theoretically be folded in several alternative ways. Viral DNA, when extracted from virions by several procedures, presents as linear single-stranded and/or linear double-stranded molecules, except when one particular commercial kit is used.

Does hepatitis C viremia or genotype predict the risk of mortality in individuals co-infected with HIV?

Background & Aims: The influence of HCV-RNA levels and genotype on HCV disease progression is not well studied. The prognostic value of these markers was investigated in HIV/HCV co-infected individuals from the EuroSIDA cohort.

Methods: EuroSIDA is a prospective cohort of 18,295 HIV-1 infected patients in 105 centres across Europe, Israel, and Argentina.

Hyaluronic acid levels predict increased risk of non-AIDS death in hepatitis-coinfected persons interrupting antiretroviral therapy in the SMART Study.

Background: In the SMART study, HIV-viral-hepatitis-coinfected persons were, compared with HIV-monoinfected persons, at higher risk of non-AIDS death if randomized to the antiretroviral therapy (ART) interruption strategy. We hypothesized that a marker of liver fibrosis, hyaluronic acid (HA), would be predictive of development of non-AIDS-related outcomes in coinfected participants in the SMART study.

Methods: All participants positive for HCV RNA or hepatitis B surface antigen (HBsAg) and with stored plasma samples were included (n=675).

An international collaboration to standardize HIV-2 viral load assays: results from the 2009 ACHI(E)V(2E) quality control study.

Accurate HIV-2 plasma viral load quantification is crucial for adequate HIV-2 patient management and for the proper conduct of clinical trials and international cohort collaborations. This study compared the homogeneity of HIV-2 RNA quantification when using HIV-2 assays from ACHI(E)V(2E) study sites and either in-house PCR calibration standards or common viral load standards supplied to all collaborators. Each of the 12 participating laboratories quantified blinded HIV-2 samples, using its own HIV-2 viral load assay and standard as well as centrally validated and distributed common HIV-2 group A and B standards (http://www.

Interferon-lambda serum levels in hepatitis C.

Background & Aims: Dendritic cells (DCs) trigger adaptive immune responses and are an important source of antiviral cytokines. In hepatitis C virus (HCV) infection DC function is markedly impaired. Thus far, studies have focused on types I and II interferon (IFN).

Influence of extraction protocol on physical properties of parvovirus B19 DNA.

While establishing a quantification standard for parvovirus B19 diagnostics, we extracted viral DNA from a high-titered human plasma by using three commercial kits. Despite similar viral DNA yields being obtained, striking differences in electrophoretic mobilities of the extracted nucleic acids were observed.

Characterisation of the epitope for a herpes simplex virus glycoprotein B-specific monoclonal antibody with high protective capacity.

Monoclonal antibody (MAb) 2c, specific for glycoprotein B of herpes simplex virus (HSV), had been shown to mediate clearance of infection from the mucous membranes of mice, thereby completely inhibiting mucocutaneous inflammation and lethality, even in mice depleted of both CD4(+) and CD8(+) cells. Additionally, ganglionic infection was highly restricted. In vitro, MAb 2c exhibits a potent complement-independent neutralising activity against HSV type 1 and 2, completely inhibits the viral cell-to-cell spread as well as the syncytium formation induced by syncytial HSV strains (Eis-Hübinger et al.

GB virus C coinfection in advanced HIV type-1 disease is associated with low CCR5 and CXCR4 surface expression on CD4(+) T-cells.

Background: Coinfection with the flavivirus GB virus C (GBV-C) is frequent in patients suffering from HIV type-1 (HIV-1) infection because of shared routes of transmission. GBV-C coinfection has been proposed to exert a beneficial influence on HIV-1 infection. In vitro studies demonstrated down-regulation of C-C chemokine receptor type 5 (CCR5) as a potential mechanism by which GBV-C modulates HIV-1 disease progression.

Phylogenetic analysis of acute hepatitis C virus genotype 4 infections among human immunodeficiency virus-positive men who have sex with men in Germany.

Background: An ongoing HCV epidemic currently affects a growing proportion of HIV-positive men who have sex with men (MSM) in Europe. Recently in the North-Rhine region of Germany, we have observed an increase in acute HCV infections of genotype 4 (HCV-4).

Aims: To characterize the current spread of HCV-4 among German MSM using a molecular epidemiological approach.

Detection of all species of the genus Alphavirus by reverse transcription-PCR with diagnostic sensitivity.

Clinical arbovirus screening requires exclusion of a broad range of viruses with as few assays as possible. We present a reverse transcription-PCR (RT-PCR) for the detection of all species of the genus Alphavirus qualified for exclusion screening (limit of detection [LOD], 5 to 100 RNA copies per reaction across all Alphavirus species; detection of viremia down to ca. 10,000 copies per ml).

Frequent hepatitis B virus rebound among HIV-hepatitis B virus-coinfected patients following antiretroviral therapy interruption.

Background: The impact of antiretroviral therapy (ART) interruption in HIV-hepatitis B virus (HBV)-coinfected patients was examined in the Strategic Management of AntiRetroviral Therapy (SMART) study.

Methods: Plasma HBV DNA was measured in all hepatitis B surface antigen-positive (HBV-positive) participants at baseline, and at months 1, 2, 4, 6, 8, 10, and 12.

Results: Among HBV-positive participants in the ART interruption (drug conservation) (n = 72) and ART continuation (virological suppression) (n = 62) arms, HBV DNA rebound of more than 1 log from baseline at months 1-4 was seen in 31-33% (P = 0.

Effects of the CCR5-Delta32 mutation on hepatitis C virus-specific immune responses in patients with haemophilia.

In hepatitis C virus (HCV) infection antiviral T cells express the CC chemokine receptor 5 (CCR5). Their recruitment to the liver is an important step in the immune response. A 32 base pair deletion in the CCR5 gene leads to reduced expression and total loss of CCR5 in CCR5-Delta32 heterozygous and homozygous subjects, respectively.

A novel diagnostic target in the hepatitis C virus genome.

Background: Detection and quantification of hepatitis C virus (HCV) RNA is integral to diagnostic and therapeutic regimens. All molecular assays target the viral 5'-noncoding region (5'-NCR), and all show genotype-dependent variation of sensitivities and viral load results. Non-western HCV genotypes have been under-represented in evaluation studies.

Effects of the CCR5-Delta32 mutation on hepatitis C virus-specific immune responses in patients with haemophilia.

In hepatitis C virus (HCV) infection antiviral T cells express the CC chemokine receptor 5 (CCR5). Their recruitment to the liver is an important step in the immune response. A 32 base pair deletion in the CCR5 gene leads to reduced expression and total loss of CCR5 in CCR5-n32 heterozygous and homozygous subjects, respectively.

Prevalence of C-terminal gag cleavage site mutations in HIV from therapy-naïve patients.

Objectives: HIV protease - as well as gag cleavage site (CS) - mutations occur in HIV with PI resistance but little is known about the prevalence of CS mutations in drug-naïve patients.

Patients And Methods: HIV samples (collected before 1997: n=94, after 1997: n=1617) from drug-naïve patients were analysed in the C-terminal gag and pol gene. Additionally, sequences from HIV Stanford database were included according to the collection date of the blood sample (before 1997: n=200, after 1997: n=375).

Spontaneous viral clearance, viral load, and genotype distribution of hepatitis C virus (HCV) in HIV-infected patients with anti-HCV antibodies in Europe.

Background: Variables influencing serum hepatitis C virus (HCV) RNA levels and genotype distribution in individuals with human immunodeficiency virus (HIV) infection are not well known, nor are factors determining spontaneous clearance after exposure to HCV in this population.

Methods: All HCV antibody (Ab)-positive patients with HIV infection in the EuroSIDA cohort who had stored samples were tested for serum HCV RNA, and HCV genotyping was done for subjects with viremia. Logistic regression was used to identify variables associated with spontaneous HCV clearance and HCV genotype 1.

Quality control assessment of human immunodeficiency virus type 2 (HIV-2) viral load quantification assays: results from an international collaboration on HIV-2 infection in 2006.

Human immunodeficiency virus type 2 (HIV-2) RNA quantification assays used in nine laboratories of the ACHI(E)V(2E) (A Collaboration on HIV-2 Infection) study group were evaluated. In a blinded experimental design, laboratories quantified three series of aliquots of an HIV-2 subtype A strain, each at a different theoretical viral load. Quantification varied between laboratories, and international standardization of quantification assays is strongly needed.

Human bocavirus: passenger or pathogen in acute respiratory tract infections?

Human bocavirus (HBoV) is a newly identified virus tentatively assigned to the family Parvoviridae, subfamily Parvovirinae, genus Bocavirus. HBoV was first described in 2005 and has since been detected in respiratory tract secretions worldwide. Herein we review the literature on HBoV and discuss the biology and potential clinical impact of this virus.

Detection of astrovirus in premature infants with necrotizing enterocolitis.

Background: Necrotizing enterocolitis (NEC) is a major cause of mortality and morbidity in very low birth weight infants (<1500 g birth weight). Although the etiology remains unknown, infectious agents could play a key role. The aim of this analysis was to examine the role of human astrovirus (HAstV) in infants with NEC.

Intrahepatic mRNA expression in hepatitis C virus and HIV/hepatitis C virus co-infection: infiltrating cells, cytokines, and influence of HAART.

Objective: Liver disease is more progressive in HIV/hepatitis C virus (HCV) co-infection than in HCV infection alone. This accelerated pathogenesis is probably influenced by differences in the composition of infiltrating inflammatory cells and the local release of inflammatory and profibrogenic cytokines.

Methods: Using quantitative real-time reverse transcriptase-polymerase chain reaction (qRT-PCR) we studied intrahepatic messenger RNA levels of cytokines and cellular markers defining distinct subsets of inflammatory cells in liver biopsies from 33 HCV-mono-infected and 40 HIV/HCV-co-infected patients.

Fifteen years of env C2V3C3 evolution in six individuals infected clonally with human immunodeficiency virus type 1.

The study of the evolution of human immunodeficiency virus type 1 (HIV-1) requires blood samples collected longitudinally and data on the approximate time point of infection. Although these requirements were fulfilled in several previous studies, the infectious sources were either unknown or heterogeneous genetically. In the present study, HIV-1 env C2V3C3 (nt 7029-7315) evolution was examined retrospectively in a cohort of hemophiliacs.

Prospective study of Human Bocavirus (HBoV) infection in a pediatric university hospital in Germany 2005/2006.

Background: Human Bocavirus (HBoV), a new species of the genus parvovirus newly detected in 2005, seems to be a worldwide distributed pathogen among children with respiratory tract infection (prevalence 2%-18%). Recently published retrospective studies and one prospective birth cohort study suggest that HBoV-primary infection occurs in infants.

Methods: Prospective single center study over one winter season (November 2005-May 2006) with hospitalized children without age restriction using PCR-based diagnostic methods.

Frequent detection of cell-associated HIV-1 RNA in patients with plasma viral load <50 copies/ml.

Despite prolonged undetectable plasma viral load some HIV-1 infected patients have been reported to develop resistance-associated mutations leading to treatment failure. The mechanisms for this phenomenon and the point of origin for residual viral evolution are still not elucidated. In order to quantify cell-associated HIV-1 RNA in patients with different levels of plasma viremia paired cell-associated HIV-1 RNA loads and plasma viral loads were determined.

Acute life threatening event (ALTE) in an infant with human coronavirus HCoV-229E infection.

In this short report we discuss the temporal association between an acute life threatening event (ALTE) and a RT-PCR confirmed coronavirus HCoV-229E infection in a 4 months old otherwise healthy infant. More detailed microbiological investigations of affected children even without apparent signs of a respiratory tract infection may help to clarify the etiology in some patients and extend our understanding of the pathogenesis. PCR-based techniques should be utilized to increase the sensitivity of detection for old and new respiratory viral pathogens in comparable cases.