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1.
AIDS Res Hum Retroviruses ; 23(12): 1481-90, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18160005

RESUMEN

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.


Asunto(s)
Genes env , Genes pol , Variación Genética , Infecciones por VIH/virología , VIH-1/genética , Secuencia de Aminoácidos , Brasil/epidemiología , Infecciones por VIH/epidemiología , Humanos , Datos de Secuencia Molecular , Filogenia , Recombinación Genética
2.
Mem. Inst. Oswaldo Cruz ; 99(8): 877-882, dez. 2004. ilus, graf
Artículo en Inglés | LILACS | ID: lil-393772

RESUMEN

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).


Asunto(s)
Humanos , Fármacos Anti-VIH , Farmacorresistencia Viral , Infecciones por VIH , VIH-1 , Terapia Antirretroviral Altamente Activa , Brasil , Variación Genética , Genotipo , Transcriptasa Inversa del VIH , Mutación , Reacción en Cadena de la Polimerasa , ARN Viral , Carga Viral
3.
Mem Inst Oswaldo Cruz ; 99(8): 877-82, 2004 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-15761606

RESUMEN

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%).


Asunto(s)
Fármacos Anti-VIH/uso terapéutico , Farmacorresistencia Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Terapia Antirretroviral Altamente Activa , Brasil , Variación Genética , Genotipo , Infecciones por VIH/virología , Transcriptasa Inversa del VIH , VIH-1/efectos de los fármacos , Humanos , Mutación , Reacción en Cadena de la Polimerasa , ARN Viral/análisis , Carga Viral
4.
Mem. Inst. Oswaldo Cruz ; 84(2): 241-3, abr.-jun. 1989.
Artículo en Portugués | LILACS | ID: lil-79143

RESUMEN

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"


Asunto(s)
Corynebacterium diphtheriae/aislamiento & purificación , Difteria/diagnóstico , Semen/patogenicidad , Corynebacterium diphtheriae/patogenicidad , Medios de Cultivo , Virulencia
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