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Aluminium coatings deposited on AA2024-T3 by the flame arc, atmospheric plasma and high velocity oxyfuel (HVOF) processes were evaluated using quantitative metallography, microhardness, adhesion, three point bend and conventional fatigue tests as well as fatigue tests on precorroded samples. Comparison of the microstructures, mechanical properties, and the fatigue and precorroded fatigue properties of samples with the three types of thermal spray coating, as well as samples of bare AA2024-T3 and Alclad AA2024-T3, revealed that HVOF is the most promising thermal spray process for the deposition of aluminium coatings, and, in particular, HVOF coatings greatly increase the fatigue and precorroded fatigue lifetimes of the AA2024-T3 substrate. [ABSTRACT FROM AUTHOR]

Changes in the hepatitis C virus (HCV) viral load (VL) were assessed in a retrospective study of 50 HIV/HCV-coinfected patients who initiated highly active antiretroviral therapy (HAART). Most patients responded to HAART [during the first 6 months, plasma HIV VL fell by a mean 1.39 log10, becoming undetectable (<400 copies/ml) in 22% and CD4+ T cells increased by a mean of 100 cells/microl], but surprisingly, 27 (54%) showed some rise and 25 (50%) showed a significant increase in the HCV VL. This figure was considered to be a minimum estimate. A majority of the patients showed an increase of less than 1 log10 that was associated with a rapid decrease in the HIV VL, whereas an increase in the HCV VL of greater than 1 log10, noted in eight patients, was associated with a baseline CD4+ cell count of less than 200 cells/microl. The increase in the HCV VL was not associated with hepatitis as determined by raised alanine transferase.

Six major genotypes of the hepatitis C virus (HCV) have been described; it is assumed to be uncommon for genotypes to change in chronically infected individuals. Venous blood samples obtained from Vietnamese-Australian injecting drug users who participated in successive studies conducted in Melbourne, Australia, were genotyped using the Bayer line probe assay and genotype confirmed by sequencing whenever possible. Three changes of HCV genotype were observed, and one infection in an individual not exposed previously. The rate of change of genotype was 3 in 11.4 person-years (py), or 26.4 per 100 py (95% CI: 8.5, 81.6). Traditionally-calculated HCV incidence was 1 in 4.3 py, or 23.3 per 100 py (95% CI: 3.3, 165.1). These data imply that HCV genotype change in injecting drug users occurs at least as frequently as infections in naive individuals, and that traditionally-calculated HCV incidence rates represent a minority of actual HCV transmission among practicing injecting drug users., (2004 Wiley-Liss, Inc.)

Hepatitis C virus (HCV) genotype and other host and viral factors influence treatment outcome in chronic HCV infection. We evaluated the effect of race and genotype on interferon and ribavirin treatment outcome in 70 Southeast Asian (SEA) and 50 white patients. Genotype was based on the 5' untranslated region (5'UTR) with a commonly used line probe assay (INNO-LiPA HCV II) that may mistype genotype 7, 8, or 9 as 1b. HCV core region sequencing resulted in reclassification of 8 genotype 1 and 25 genotype 1b SEA subjects as genotype 7, 8, or 9. Twenty-six SEA genotype 7, 8, and 9 (79%) and 10 SEA true genotype 1b (59%) patients achieved a sustained virologic response (SVR) compared with 15 (34%) white genotype 1b patients. Logistic regression analysis showed that SEA patients with genotype 7, 8, or 9 were more likely to achieve a SVR than white genotype 1b patients (OR 16.56; 95%CI 4.16, 65.91) as were SEA true genotype 1b patients compared with white genotype 1b patients (OR 4.63; 95%CI 1.19, 18.04). In conclusion, a proportion of SEA patients classified by INNO-LiPA as genotype 1b were in reality genotype 7, 8, or 9. In comparison with white genotype 1b patients, both SEA genotype 1b and SEA genotype 7, 8, and 9 patients showed a significantly greater SVR. HCV core sequencing was necessary to determine genotype accurately in persons potentially exposed to HCV genotypes 7, 8, or 9. This study also supports the concept that race and ethnicity are important determinants of treatment outcome in HCV infected patients.

An investigation was done of the evidence for transmission of human immunodeficiency virus (HIV) from an HIV-positive man to several male and female sex contacts. Phylogenetic analysis of sequences from the gag and env genes showed a close relationship between the predominant virus strains from the source and 2 contacts. However, the likelihood that a female contact was infected by the source could not be determined, despite contact tracing indicating that this may have occurred. One male, shown by contact tracing and molecular evidence to have been infected by the source, subsequently transmitted HIV to his female sex partner. HIV sequence from a plasma sample used as a control in the phylogenetic analysis contained env and gag sequences that were closely related to those from the source. An epidemiologic link between these 2 individuals was subsequently confirmed by contact tracing.

Objective: To determine the prevalence of hepatitis G virus (HGV) carriage in Queensland blood donors., Design: Cross-sectional survey with retrospective longitudinal study of HGV-positive donors., Setting: Brisbane Red Cross Blood Bank, 1995., Subjects: 100 consecutive blood donors attending the Blood Bank on two days in October 1995 and 20 blood donors with a raised plasma alanine aminotransferase (ALT) level on their last donation., Outcome Measures: Presence of HGV RNA by reverse transcription polymerase chain reaction (RT-PCR) in currently donated blood and in blood samples archived for up to 34 months. RT-PCR used two different reverse transcription methods and three different specific sets of primers and probes., Results: Five of the 120 blood donors were positive for HGV RNA by all RT-PCR methods (four of the 100 with normal ALT levels [4%] and one of the 20 with raised ALT levels [5%]). Retrospective testing of archived samples showed that four of these five had been persistently HGV RNA-positive for at least two years, while the fifth had been HGV RNA-negative on two donations before becoming HGV RNA-positive. No risk factors were identified for this donor., Conclusions: A relatively large number of Queensland blood donors (4%) are persistently HGV RNA-positive.