Alta prevalência e associação do subtipo não-B do vírus HIV-1 com risco específico de transmissão sexual entre pacientes virgens de tratamento antirretroviral em Porto Alegre, Brasil

In South Brazil the circulation of two HIV-1 subtypes with different characteristics represents an important scenario for the study of the impact of HIV-1 diversity on the evolution of the HIV-1 epidemic and AIDS disease. HIV-1 B, the predominant variant in industrialized countries and HIV-1 C, the most prevalent subtype in areas with rapid epidemic growth, are implicated in most infections. We evaluated blood samples from 128 antiretroviral (ARV) naïve patients recruited at entry to the largest HIV outpatient service in Porto Alegre. Based on partial pol region sequencing, HIV-1 C was observed in 29%, HIV-1 B in 22.6% and, the recently identified CRF31_BC, in 23.4% of 128 volunteers. Other variants were HIV-1 F in 10% and other mosaics in 5.5%. In order to evaluate the association of socio-behavioral characteristics and HIV-1 subtypes, interviews and laboratory evaluation were performed at entry. Our data suggest an established epidemic of the three major variants, without any evidence of partitioning in either of the subgroups analyzed. However, anal sex practices were associated with subtype B, which could indicate a greater transmissibility of non-B variants by vaginal intercourse. This study provides baseline information for epidemiologic surveillance of the changes of the molecular characteristics of HIV-1 epidemics in this region.No sul do Brasil a circulação de dois subtipos de HIV-1 com características diferentes representa importante cenário para o estudo do impacto da diversidade do HIV-1 na evolução da epidemia e na AIDS. O HIV-1 B, variante predominante nos países industrializados e o HIV-1 C, o subtipo mais prevalente em áreas com maiores taxas de crescimento da epidemia, estão implicados na maioria das infecções. Avaliamos amostras de sangue de 128 pacientes sem exposição a antirretrovirais, recrutados ao ingressarem no maior serviço ambulatorial de HIV/AIDS de Porto Alegre. Com base no sequenciamento parcial da região pol, o HIV-1 C foi observado em 29%, HIV-1 B em 22,6% e uma forma recombinante recentemente descrita, CRF31_BC, foi observada em 23,4% entre 128 voluntários. Outras variantes encontradas foram HIV-1 F em 10% e outros mosaicos em 5,5%. Para avaliar associações entre características sócio-comportamentais e subtipos do HIV-1 foram realizadas entrevistas e exames laboratoriais na entrada do estudo. Nossos dados sugerem uma epidemia estabelecida dessas três variantes principais, sem evidência de compartilhamento em nenhum subgrupo analisado. Entretanto, prática sexual anal se mostrou associada à transmissão de subtipo B, o que pode indicar maior transmissibilidade das variantes não-B por intercurso vaginal. Este estudo permite delinear uma linha de base para o monitoramento epidemiológico das mudanças nas características moleculares da epidemia do HIV-1 nesta região

High prevalence and association of HIV-1 non-B subtype with specific sexual transmission risk among antiretroviral naïve patients in Porto Alegre, RS, Brazil

In South Brazil the circulation of two HIV-1 subtypes with different characteristics represents an important scenario for the study of the impact of HIV-1 diversity on the evolution of the HIV-1 epidemic and AIDS disease. HIV-1 B, the predominant variant in industrialized countries and HIV-1 C, the most prevalent subtype in areas with rapid epidemic growth, are implicated in most infections. We evaluated blood samples from 128 antiretroviral (ARV) naïve patients recruited at entry to the largest HIV outpatient service in Porto Alegre. Based on partial pol region sequencing, HIV-1 C was observed in 29%, HIV-1 B in 22.6% and, the recently identified CRF31_BC, in 23.4% of 128 volunteers. Other variants were HIV-1 F in 10% and other mosaics in 5.5%. In order to evaluate the association of socio-behavioral characteristics and HIV-1 subtypes, interviews and laboratory evaluation were performed at entry. Our data suggest an established epidemic of the three major variants, without any evidence of partitioning in either of the subgroups analyzed. However, anal sex practices were associated with subtype B, which could indicate a greater transmissibility of non-B variants by vaginal intercourse. This study provides baseline information for epidemiologic surveillance of the changes of the molecular characteristics of HIV-1 epidemics in this region

Characterisation of microbial attack on archaeological bone

As part of an EU funded project to investigate the factors influencing bone preservation in the archaeological record, more than 250 bones from 41 archaeological sites in five countries spanning four climatic regions were studied for diagenetic alteration. Sites were selected to cover a range of environmental conditions and archaeological contexts. Microscopic and physical (mercury intrusion porosimetry) analyses of these bones revealed that the majority (68%) had suffered microbial attack. Furthermore, significant differences were found between animal and human bone in both the state of preservation and the type of microbial attack present. These differences in preservation might result from differences in early taphonomy of the bones. © 2003 Elsevier Science Ltd. All rights reserved