Lack of tax diversity for tropical spastic paraparesis/human T-cell lymphotropic virus type 1 (HTLV-I) associated myelopathy development in HTLV-I-infected subjects in São Paulo, Brazil

The product of human T-cell lymphotropic virus type 1 (HTLV-1) tax gene has a transactivating effect of the viral and cellular gene expression. Genetic variations in this gene have been correlated with differences in clinical outcomes. Based upon its diversity, two closely related substrains, namely tax A and tax B, have been described. The tax A substrain has been found at a higher frequency among human T-cell leukemia virus type 1 (TSP/HAM) patients than among healthy HTLV-I-infected asymptomatic subjects in Japan. In this study, we determined the distribution of tax substrains in HTLV-I-infected subjects in the city of São Paulo, Brazil. Using the ACCII restriction enzyme site, we detected only tax A substrain from 48 TSP/HAM patients and 28 healthy HTLV-I carriers. The sequenced tax genes from nine TSP/HAM patients and five asymptomatic HTLV-I carriers showed a similar pattern of mutation, which characterizes tax A. Our results indicate that HTLV-I tax subtypes have no significant influences on TSP/HAM disease progression. Furthermore, monophyletic introduction of HTLV-I to Brazil probably occurred during the African slave trade many years ago

Co-infecção HIV/HCV em pacientes de Botucatu e região HIV/HCV co-infection in patients from Botucatu and region (Brazilian cities)

Devido à similaridade nas rotas de transmissão, a co-infecção HIV/HCV é freqüente, afetando em média 30 a 50% dos portadores de HIV. O presente estudo visou avaliar uma possível associação entre os subtipos do HIV e genótipos do HCV em pacientes co-infectados, com base na análise das freqüências em pacientes mono e co-infectados. Para determinação da freqüência dos subtipos HIV e genótipos HCV, foram analisados respectivamente 124 e 496 pacientes mono-infectados. O estudo da co-infecção foi realizado num grupo de 150 pacientes HIV positivos e esteve presente em 22 (14,7%) dos pacientes. A freqüência dos subtipos do HIV-1 em mono-infectados foi: subtipo B (85,5%), subtipo F (12,9%) e recombinante B/F (1,6%), enquanto nos genótipos HCV foi: 1a (25%), 1b (29,4%), 1a/1b (3,6%), 3a (35%), 2 (1,8%) e 5 (0,4%). Nos co-infectados o padrão de distribuição dos subtipos HIV-1 é semelhante aos mono-infectados, ou seja, subtipo B (85,0%), seguido do subtipo F (15,0%). A distribuição de freqüência de genótipos HCV nos co-infectados foi: 1a (36,3%), 1b (27,3%), 1a/1b (9,1%) e 3a (27,3%) mostrando um aumento de 10% na freqüência do genótipo 1, queda de 7,7% no genótipo 3 e ausência de outros genótipos. A análise estatística de associação entre os subtipos HIV e genótipos HCV (Goodman) mostrou que no genótipo 1 (HCV) ocorreu predominância do subtipo B, enquanto no genótipo 3 (HCV) a distribuição dos subtipos B e F (HIV-1) foi casual. Isto aponta para a necessidade de mais estudos desse grupo e um maior valor amostral.<br>HIV/HCV co-infection is a frequent event due to the similarity of the means of transmission of both viruses; 30-50% of HIV infected individuals are co-infected¹. This paper assesses the possible association among HCV and HIV genotypes in co-infected patients based on frequency distribution in mono and co-infected patients. To determine HIV and HCV genotype frequency 124 and 496 respectively, mono infected patients were analyzed. The study of co-infection was performed in 150 HIV positive patients and 22 (14.7%) patients were found. The frequency of HIV-1 subtypes was 106 B subtype (85.5%), 16 F (12.9%), and 2 B/F recombinant (1.6%); HCV genotypes were 1a (25%), 1b (29.4%), 1a/1b (3.6%), 3a (35%), 2 (1.8%) and 5 (0.4%). The HCV genotype could not be determined in 6.3% of samples using the technique. The HIV-1 subtype distribution standard was B subtype (85.0%) and F subtype (15.0%) in mono-infected as in co-infected. The frequency distribution of HCV genotypes in co-infected was 1a (36.4%), 1b (27.3%), 1a/1b (9.1%) and 3a (27.3%). These results showed a 10% increase in frequency of 1a genotype, 7.7% decrease in 3 genotype and lack of other genotypes. The statistical analysis of association of HCV genotypes and HIV-1 subtypes (Goodman Test) showed a predominance of the B HIV subtype among HCV genotype 1, and among HCV genotype 3 the distribution of B and F HIV subtypes was casual. These results suggest the need for further studies in this group and larger samples