RESUMO
"New method for molecular typing of human enteroviruses: characterization of ""untypeable"" strains isolated in Madagascar"" : Enteroviruses; members of the family icornaviridae;are responsible for a wide variety of diseases and represent a major public health hazard. Typing of non polio enterovirus (NPEV) infection is traditionally based on a serum neutralization assay. However; this method is time-consuming; labor-intensive; expensive; and may fail to identify antigenic variation. A new molecular typing involving partial sequencing of the genome has been recently developed. In this study; 46 NPEV strains were analyzed; including 37 antigenicaly ""untypeable"" viruses. Partial sequencing of the C-end of the viral capsid protein VP1 and pairwise identity with the prototype strains allow us to assign a serotype for all ""untypeable"" viruses. The result show a large number and wide variety of Coxsackieviruses A which belong to the HEV-C species and also Echoviruses and Coxsackieviruses B of the HEV-B species. This method may be useful to identify all NPEV serotypes in Madagascar and to assess the possible impact of circulating NPEV populations; as we enter the final stage of poliomyelitis eradication."
Assuntos
Enterovirus , Dados de Sequência MolecularRESUMO
Two non-isotopic polymerase chain reaction (PCR) methods were evaluated by testing blood from 41 HIV-1-seropositive and 16 HIV-1-seronegative Ugandan mothers and 56 of their children (aged 0.5-15.0 months). Amplification of HIV-1 sequences was performed in duplicate using a biotinylated primer pair to the gag region (SK 462-431) and nested primer pairs (JA 17-20) to the pol region of HIV-1. gag sequences were hybridized using a microtiter plate coated with the SK 102 probe followed by colorimetric detection using an avidin-horseradish peroxidase conjugate and tetramethylbenzidine/peroxide substrate. pol sequences were detected on agarose gel stained with ethidium bromide. Results of HIV-1 PCR analysis showed that 40 out of 41 (98pc) seropositive mothers and 10 out of 29 (34pc) seropositive children had detectable HIV-1 gag and pol sequences. None of the 16 seronegative mothers nor 27 seronegative or Western blot-indeterminate children had detectable HIV-1 sequences. Our results suggest that non-isotopic PCR methods are sensitive; specific; and potentially useful in the early diagnosis of HIV-1 infection in developed and developing countries