RESUMO
This study analyzed the genes pol and env to determine the genetic variability of HIV-1 in Central Brazil. Forty-one isolates of HIV-1-infected individuals had protease, reverse transcriptase, and C2C3/ env amplified by nested PCR and sequenced. The subtype was determined by the program REGA and phylogenetic analyses. The samples identified as putative recombinant forms were analyzed by SimPlot. A high prevalence of subtype B (95.1%) was observed, followed by mosaic viruses B/F (4.9%). The amino acid sequences from 30 HIV-1 isolates were analyzed for the antigenic intrasubtype diversity. The most prevalent gp120 V3 loop motif was the GPGR (United States/Europe) (43.3%), described in B and F subtypes, followed by the GPGK tetrapeptide (10%). The Brazilian variant B" (GWGR), GFGR, and GLGR tetrapeptides were found in 6.7%. Other V3 variants were found in eight isolates (26.7%). Phylogenetic tree analysis was also performed in order to verify the relationship of the HIV-1 samples from Central Brazil with other HIV-1 sequences that circulate in Brazil. The subtype B sequences from Central Brazil formed a polyphyletic cluster in the tree, indicating that these strains are similar to those from other geographic regions. These results contribute to the understanding of HIV in Brazil, and may prove useful for the development of vaccine candidates.
Assuntos
Genes env , Genes pol , Variação Genética , Infecções por HIV/virologia , HIV-1/genética , Sequência de Aminoácidos , Brasil/epidemiologia , Infecções por HIV/epidemiologia , Humanos , Dados de Sequência Molecular , Filogenia , Recombinação GenéticaRESUMO
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).
Assuntos
Humanos , Fármacos Anti-HIV , Farmacorresistência Viral , Infecções por HIV , HIV-1 , Terapia Antirretroviral de Alta Atividade , Brasil , Variação Genética , Genótipo , Transcriptase Reversa do HIV , Mutação , Reação em Cadeia da Polimerase , RNA Viral , Carga ViralRESUMO
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, Brasilia, 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% of the samples clustered with subtype B and the remaining 4% with HIV-1 subtype F sequences. One major protease inhibitor resistance-associated mutation, I50V, was detected in 38% of the samples. Minor mutations were also found at the protease gene: L10I/V (7%), K20M (2%), M36I (11%), L63P (20%), A71T (2%), and V77I (7%). Many mutations associated with reduced susceptibility to nucleoside or non-nucleoside reverse transcriptase inhibitors were detected: M41L (11%), E44D (4%), D67N (11%), T69D (2%), K70R (11%), L74V (2%), L100I (4%), K103N (18%), V118I (9%), Y181C (11%), M184V (18%), G190A (4%), T215Y (4%), and K219E (4%). This study has shown that 84% 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%), the NNRTIs delavirdine, nevirapine (31%), and efavirenz (24%), and the NRTIs lamivudine (18%), abacavir, and zidovudine (13%).
Assuntos
Fármacos Anti-HIV/uso terapêutico , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Terapia Antirretroviral de Alta Atividade , Brasil , Variação Genética , Genótipo , Infecções por HIV/virologia , Transcriptase Reversa do HIV , HIV-1/efeitos dos fármacos , Humanos , Mutação , Reação em Cadeia da Polimerase , RNA Viral/análise , Carga ViralRESUMO
Descrevemos o isolamento de Corynebacterium diphtheriae toxígeno de espermocultura. O microrganismo foi identificado pelo teste de fluorescência sob luz ultravioleta, pesquisa da enzima pirazina-carboxilamidase (Pyz), testes de virulência in vitro e in vivo (imunodifusäo radial simples, cultura de células e teste intradérmico em cobaio). A amostra foi inicialmente considerada atoxígena pelo teste de imunodifusäo radial simples, mas sua virulência foi observada posteriormente quando os testes acima foram aplicados. Sem adecuada especificaçäo, a amostra poderia ter sido considerada como um "difteróide"