Antiretroviral resistance and genetic diversity of human immunodeficiency virus type 1 isolates from the Federal District, Central Brazil

In the context of universal access to antiretroviral therapy, the surveillance of human immunodeficiency virus type 1 (HIV-1) genetic diversity and resistance becomes pivotal. In this work our purpose was to describe the genetic variability; prevalence of drug-resistance mutations; and genotypic resistance profiles in HIV-1 infected individuals under antiretroviral treatment, from the Federal District, Brasília, Central Brazil. The entire viral protease and codons 19 to 234 of the reverse transcriptase gene from 45 HIV-1 isolates were amplified and sequenced for subtyping and genotyping. By phylogenetic analysis, 96 percent of the samples clustered with subtype B and the remaining 4 percent with HIV-1 subtype F sequences. One major protease inhibitor resistance-associated mutation, I50V, was detected in 38 percent of the samples. Minor mutations were also found at the protease gene: L10I/V (7 percent), K20M (2 percent), M36I (11 percent), L63P (20 percent), A71T (2 percent), and V77I (7 percent). Many mutations associated with reduced susceptibility to nucleoside or non-nucleoside reverse transcriptase inhibitors were detected: M41L (11 percent), E44D (4 percent), D67N (11 percent), T69D (2 percent), K70R (11 percent), L74V (2 percent), L100I (4 percent), K103N (18 percent), V118I (9 percent), Y181C (11 percent), M184V (18 percent), G190A (4 percent), T215Y (4 percent), and K219E (4 percent). This study has shown that 84 percent of the studied population from the Federal District, showing evidences of therapy failure, presented viral genomic mutations associated with drug resistance. The main antiretrovirals to which this population showed resistance were the PI amprenavir (38 percent), the NNRTIs delavirdine, nevirapine (31 percent), and efavirenz (24 percent), and the NRTIs lamivudine (18 percent), abacavir, and zidovudine (13 percent).

Hepatitis C virus genotypes in blood donors from the Federal District, Central Brazil

The objective of this study was to characterize hepatitis C virus (HCV) genotypes in blood donors from the Federal District, Central Brazil, and to compare HCV screening by serological assays and reverse transcriptase polymerase chain reaction (RT-PCR). Plasma samples from 57 individuals with reactive or indeterminate results in serological anti-HCV screening assays (ELISA or EIA) were tested for HCV RNA by RT-PCR. The results from a confirmatory LIA serological assay were also evaluated. The 5' non-coding region of the HCV genome was amplified from 41 PCR positive samples (71.9 percent), which were further characterized by nucleotide sequencing analysis. Of these, 60.9 percent were of HCV genotype 1 and 39.1 percent of genotype 3.

Prevalence of human papillomavirus type 16 variants in the Federal District, Central Brazil

We report the prevalence of human papillomavirus type 16 (HPV-16) variants in women with cervical lesions from the Federal District, Central Brazil. We analyzed 34 HPV-16 samples, identifying the sequence variations of E6 and L1 genes and correlating variant frequency with disease status. The most prevalent HPV-16 variant was the European (50 percent), followed by Asian-American (41.2 percent), African-1 (5.9 percent), and African-2 (2.9 percent). European and non-European variants appeared in equal frequencies among the cytological types of lesions - atypical squamous or glandular cells of undetermined significance, cytological alterations suggesting HPV infection, cervical intraepithelial neoplasias, squamous cell carcinoma, and adenocarcinoma.

Prevalence of human papillomavirus types in women with pre-neoplastic and neoplastic cervical lesions in the Federal District of Brazil

As a contribution to the public health authorities in planning prophylactic and therapeutic vaccine strategies, we describe the prevalence of human papillomavirus (HPV) types in women presenting abnormal cytological results in Pap smear screening tests in the Federal District, Central Brazil. We studied 129 cervical scraping samples from women whose cytological tests showed either pre-neoplastic or neoplastic lesions. Amplification of HPV DNA was performed by polymerase chain reaction using consensus primers MY09 and MY11 followed by identification of isolates by restriction fragment length polymorphism. We detected HPV DNA in 62 percent of the samples, including HPV-16 in 43.8 percent, HPV-58 in 12.5 percent, HPV-31 in 10 percent, HPV-53 in 6.3 percent, each of HPV-18 and HPV-33 in 3.8 percent of the isolates. Other types (HPV-35, -52, -66, -CP8304, -6, -11, and -CP8061) were less frequent (= or < 2.5 percent each). The prevalence of HPV-58 was relatively higher in this population than in data in South America, but similar to results obtained in other studies in Latin America, Europe, and Eastern Asia. Case-control studies need to be carried out to establish the association between the prevalence of HPV types specially the less frequent high-risk types and cervical cancer.

Prevalence of human papillomavirus in penile carcinoma / Prevalência do papilomavirus humano no carcinoma peniano

Introdução: O carcinoma de células escamosas corresponde a 95 porcento dos tumores penianos malignos. Sua relação com o papilomavirus humano (HPV) tem sido estudada por vários autores. Nosso estudo descreve o predomínio do DNA do HPV nos carcinomas de células escamosas penianas em Brasília, Brasil. Materiais e métodos: O DNA do papilomavirus humano foi amplificado por reação em cadeia de polimerase (RCP) utilizando os "primers" GP5+/GP6+ e pU-1M/pU-2R, após a extração do material embebido em parafina, de 59 pacientes com carcinoma peniano. HPV isolados foram classificados pela digestão com enzimas de restrição e seqüência automática. Resultados: DNA de boa qualidade foi obtido de 37 amostras das 59 selecionadas previamente. O predomínio do DNA do HPV variou de 13,5 porcento (5/37) à 64,8 porcento (19,24) quando consideramos amplificação com "primers" pU-1M/pU-2R ou GP5+/GP6+, respectivamente. O HPV-16 foi o único tipo detectado. Conclusões: Nossos dados indicam que GP5+/GP6+RPC fornecem uma boa taxa de detecção do DNA do HPV e classificação em tecidos fixados com formol e embebidos em parafina. O predomínio do DNA do HPV pode der considerado alto quando comparado aos dados de outros estudos sul-americanos. A alta freqüência do HPV-16 e a baixa ocorrência do HPV-18 estão de acordo com os nossos resultados numa população feminina da mesma região do Brasil. Investigações adicionais devem ser conduzidas para avaliar a freqüência dos tipos de HPV associados a outras anomalias epiteliais penianas e diferentes tipos de neoplasias assim como em pacientes assintomáticos da região central do Brasil.