Epidemiology of hepatitis C virus infection among injecting drug users in Australia.

Study Objective: To review the epidemiology of hepatitis C virus (HCV) infection among injecting drug users (IDUs) in Australia, and consider needs for further research and prevention policies and programmes.

Design: (1) Review of the results of surveillance for HCV; (2) review of published literature on prevalence, incidence, and risk factors for HCV among IDUs; and (3) reconstruction of incidence rates from prevalence studies of HCV in IDUs.

Setting And Participants: Field and clinic based studies of IDUs in Australia.

Intracellular retention of duck hepatitis B virus large surface protein is independent of preS topology.

The mechanism of intracellular retention for the large surface protein (L) of duck hepatitis B virus (DHBV) was analyzed by examination of the transmembrane topologies and secretory properties of a collection of DHBV L mutants and compared with that of human hepatitis B virus (HBV) L. Our results demonstrate that, in contrast to its HBV counterpart, intracellular retention of DHBV L does not depend on the cytosolic disposition of its preS domain. L mutants with either cytosolic or lumenal preS were mostly retained in the absence of the small surface protein (S), whereas coexpression with S resulted in efficient secretion of both topological forms.

High level expression of the capsid protein of hepatitis E virus in diverse eukaryotic cells using the Semliki Forest virus replicon.

The capsid protein of hepatitis E virus (HEV) is encoded by open reading frame 2 (ORF 2) and exhibits variable processing when expressed in insect and COS cells, but nothing is known of its processing in cells relevant to its replication. The full-length ORF 2 protein was expressed at high levels in mammalian cells by insertion of ORF 2 in the Semliki Forest virus (SFV) replicon to generate rSFV/HEV ORF 2K. Expression of the capsid protein was detected readily by metabolic labelling and indirect immunofluorescence in BHK-21 cells transfected with RNA transcripts derived from rSFV/HEV ORF 2K.

Risk factors associated with hepatocellular carcinoma notified to the Anti-Cancer Council of Victoria in 1991-1992.

The study aimed to estimate the prevalence of risk factors for liver disease, particularly hepatitis B virus (HBV) and hepatitis C virus (HCV) infection, in a population-based series of hepatocellular carcinoma, and to assess the feasibility of retrospective surveys in determining risk factors for hepatocellular carcinoma. A survey of all cases of hepatocellular carcinoma diagnosed in 1991 and 1992 documented the high contribution of alcoholic cirrhosis, particularly in Australian-born men. Low levels of testing for HBV and HCV made their contribution to hepatocellular carcinoma uncertain.

Rubella virus replication complexes are virus-modified lysosomes.

Replication complexes are membrane-bound cytoplasmic vacuoles involved in rubella virus (RV) replication. These structures can be identified by their characteristic morphology at the electron microscopy (EM) level and by their association with double-stranded (ds) RNA in immunogold labeling EM studies. Although these virus-induced structures bear some resemblance to lysosomes, their exact nature and origin are unknown.

Human immunodeficiency virus type 1 (HIV-1)-specific T cell responses correlate with control of acute HIV-1 infection in macaques.

Macaca nemestrina efficiently control acute human immunodeficiency virus type 1 (HIV-1) infection. The roles of helper (Th) and cytotoxic (CTL) T cells in controlling acute HIV-1 infection in both peripheral blood and lymph node mononuclear cells (PBMC and LNMC) were assessed in this model. Th and CTL responses to HIV-1 were detected within 2 weeks following HIV-1 infection, and CTL responses to HIV-1 antigens peaked at 4 weeks after infection (>100 HIV-specific CTL/10[6] PBMC), coincident with reductions of HIV-1 RNA and DNA levels in peripheral blood.

Effects of monocyte purification and culture on integrin expression.

Selective alterations in the surface expression of members of the LeuCAM (leukocyte cell adhesion molecule) family of integrins occur during in vitro culture of human monocytes. Such changes may relate in part to cellular maturation, but also to activation following purification and culture of monocytes. In this paper, we examined the effects of monocyte isolation, adherence during culture and endotoxin exposure on the expression of these molecules and the ligand for LFA-1, ICAM-1 (CD54).

Exposure to hepatitis A virus among blood donors, injecting drug users and prison entrants in Victoria.

To assess prevalence of exposure to hepatitis A virus (HAV) among injecting drug users (IDUs) and prison entrants in Victoria, and to compare this with prevalence of HAV among a reference population of blood donors, sera stored from two previous studies and from randomly selected blood donors were tested for total antibody to HAV. The first study was a longitudinal study of field-recruited IDUs from 1990 to 1992 and the second was a study of all prison entrants in 1991-92 (both studies were carried out in Victoria); blood donors were from the Australian Red Cross Blood Bank Victoria in 1995. Forty-five per cent of 2175 prison entrants and 51% of 293 IDUs were seropositive for HAV, compared with 30% of 2995 blood donors.

Methadone maintenance and hepatitis C virus infection among injecting drug users.

Harm reduction strategies for the prevention of transmission of human immunodeficiency virus (HIV) transmission among injecting drug users (IDUs) have been widely implemented in Australia and are seen to have been effective in preventing the spread of HIV. A major strategy has been increasing the availability of and accessibility to methadone maintenance therapy (MMT) programmes. We have reviewed the experience of a major MMT general practice with hepatitis C virus (HCV) infection from 1991 to 1995.

HIV risk behaviour and HIV testing of psychiatric patients in Melbourne.

Objectives: Patients with chronic mental illnesses constitute an important risk group for HIV infection overseas. This study aimed to determine the prevalence of risk behaviours associated with HIV transmission and factors associated with HIV testing in psychiatric patients in Melbourne.

Methods: Inpatients and outpatients completed an interviewer-administered questionnaire which covered demographics, psychiatric diagnosis, risk behaviour, and HIV education and testing.

New advances and horizons in immunisation.

Scientific and technological advances will make it possible within the next decade to vaccinate against a number of infectious diseases for which hitherto no active immunisation has been available. This article considers what vaccines are likely to be licensed for use in the next decade and the possible indications for their use. Combination vaccines that provide protection against a greater number of diseases while not increasing the number of visits or injections per visit will be an important feature of expanding the infant vaccination schedule.

Quantification of infectious duck hepatitis B virus by radioimmunofocus assay.

A simple method is described for the precise quantification of infectious duck hepatitis B virus (DHBV) in cell culture, using a radioimmunofocus assay (RIFA). Primary duck hepatocyte cell cultures were infected with serial dilutions of viral samples as for a plaque assay, but then maintained with liquid overlay medium. After incubation for up to 14 days, cell monolayers were fixed with acetone, then stained with a monoclonal antibody to DHBV L protein followed by secondary antibody labelled with 125I.

Incidence of bloodborne virus infection and risk behaviours in a cohort of injecting drug users in Victoria, 1990-1995.

Objective: To assess changes in risk behaviours for transmission of bloodborne viruses and incidences and prevalences of these viruses in a field-recruited cohort of injecting drug users.

Design: Prospective longitudinal cohort study.

Setting: Metropolitan and rural Victoria, June 1990 to December 1995.

An actual use comparison of condoms meeting Australian and Swiss standards: results of a double-blind crossover trial.

The performance of condoms in actual use has been poorly researched in the past, especially in comparing condoms that met different quality control standards as indicated by laboratory testing. The present study used a double-blind crossover design to compare the performance of 2 types of condoms in actual use; one that met the Australian and International Organization for Standardization (ISO) standards for condom quality and one that met the more stringent Swiss Quality Seal requirements. Ninety-two men recruited from Metropolitan Melbourne completed a self-report diary sheet after each condom was used which assessed the performance of the condom and the conditions under which it was used.

GM-CSF and its effects on replication of HIV-1 in cells of macrophage lineage.

Granulocyte-macrophage colony-stimulating factor (GM-CSF) is a hemopoetic growth factor that is a member of the four-helix bundle family of cytokines and growth factors. It regulates the proliferation and differentiation of granulocytes and cells of macrophage lineage from bone marrow progenitor cells, mediating these activities through binding to its receptor. Most studies examining the effects of GM-CSF on HIV-1 replication in primary monocytes and macrophages, and in related cell lines, have demonstrated augmentation of HIV-1 expression in vitro, although some reports have been at variance with these findings.

Amino-terminal epitopes are exposed when full-length open reading frame 2 of hepatitis E virus is expressed in Escherichia coli, but carboxy-terminal epitopes are masked.

We constructed a panel of overlapping and non-overlapping fragments of cDNA derived from open reading frame 2 (ORF2) of hepatitis E virus (HEV) and fused to the gene encoding glutathione S-transferase (GST), from which proteins were expressed in Escherichia coli. IgG-specific immunoreactivity against each protein was measured by Western immunoblotting using sera from experimentally infected Rhesus macaques (Macaca mulatta) or from HEV-infected patients. Under these conditions, full-length ORF2 protein (GST-ORF2) was strongly reactive with acute-phase sera from either macaques or patients, but was poorly reactive with convalescent sera.

Effects of HIV-1 on the surface expression of LFA-1 on cultured monocytes.

CD11a, the alpha chain of LFA-1, which is a member of the LeuCAM family of integrins, has been implicated in the formation of HIV-induced syncytia and may contribute to the depletion of CD4-positive lymphocytes seen in patients with HIV infection. In this study, we examined the effects of HIV-1 infection on the expression of CD11a on cultured monocyte-derived macrophages (MDMs). Monocytes isolated from peripheral blood and maintained in suspension culture were infected in vitro with a monocytotropic variant of HIV-1 (Ba-L).

The epidemiology of notified genital Chlamydia trachomatis infection in Victoria, Australia: a survey of diagnosing providers.

Data on 259 notified cases of genital chlamydia infection diagnosed in Victoria Australia in January and February 1995 were augmented by call-back. Risk factor data was available for 221. Patients were primarily adolescents or young adults (median age 23 years); 66% were women.

Exposure to hepatitis B and C of tattooists in Victoria in 1984.

Although tattooing is recognized as a risk factor for transmission of hepatitis C, the efficiency with which transmission occurs is unknown. Sera stored from a serosurvey of tattooists undertaken in 1984 to test for human immunodeficiency virus (HIV) provided the opportunity to determine the prevalence of serological markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) in tattooists at that time. The stored sera had been obtained from five unregistered and 36 of 37 (97%) of the registered tattooists operating in 1984.

Constitutive expression of p50 homodimer in freshly isolated human monocytes decreases with in vitro and in vivo differentiation: a possible mechanism influencing human immunodeficiency virus replication in monocytes and mature macrophages.

Human immunodeficiency virus type 1 (HIV-1) replicates more efficiently in vitro in differentiated macrophages than in freshly isolated monocytes. We investigated whether this may be partly explained by changes in expression of NF-kappaB with monocyte differentiation. We demonstrated that constitutive expression of NF-kappaB in primary human monocytes changed significantly with differentiation in vitro to monocyte-derived macrophages (MDMs) and differentiation in vivo to alveolar macrophages (AMs).

Detection and subgrouping of respiratory syncytial virus directly from nasopharyngeal aspirates.

OBJECTIVE: To develop a reverse transcription-polymerase chain reaction (RT-PCR)-based assay to identify the subgroup of the infecting respiratory syncytial virus (RSV) strain directly from nasopharyngeal aspirates (NPAs). METHODS: A total of 154 NPAs which were positive for RSV antigen by direct immunofluorescence were subjected to RT-PCR. The primers used were designed to give products for subgroup A and B which were of different sizes and easily visualized on agarose electrophoresis.

The nfkb1 promoter is controlled by proteins of the Ets family.

The gene encoding NFKB1 is autoregulated, responding to NF-kappa B/Rel activation through NF-kappa B binding sites in its promoter, which also contains putative sites for Ets proteins. One of the Ets sites, which we refer to as EBS4, is located next to an NF-kappa B/Rel binding site, kB3, which is absolutely required for activity of the promoter in Jurkat T cells in response to activation by phorbol 12-myristate 13-acetate (PMA), PMA/ionomycin, or the Tax protein from human T cell leukemia virus type I. We show that EBS4 is, required for the full response of the nfkb1 promoter to PMA or PMA/ionomycin in Jurkat cells.