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HIV-1 transmitted drug resistance (TDR) mutations may reduce the efficacy of antiretroviral therapy (ART), but pre-treatment testing to determine the virus genotype can improve the efficacy of ART. Unfortunately, issues related to cost and logistics of pre-treatment testing limit its use in resource-limited settings. We studied 596 ART-naive individuals who were newly diagnosed from 2014 to 2016 in São Paulo, Brazil, to evaluate TDR and virological outcome after 48 weeks of genotype-guided therapy. One or more TDR (based on the WHO surveillance list) was observed in 10.9% (CI 95%, 8.6-13.6) of the sequences, the most common of which was the K103 N mutation, which confers resistance to first-generation drugs of the non-nucleoside reverse transcriptase inhibitor (NNRTI) antiretroviral drug class. Dual-class (1%, 6/596) and triple-class (0.34%, 2/596) resistance were uncommon. After 48 weeks of treatment with ART, infection was suppressed to below 200 copies/mL in most patients (95%), with full suppression (RNA target not detected) in 65%. The following characteristics at patient enrollment were independently associated with a lack of full suppression: CD4 T cell counts below 500 cells/µL, viremia above 100,000 copies/mL, older age, and TDR to NNRTI. The rates of resistance were intermediate, but genotype-guided therapy resulted in high rates of viral suppression. The observed resistance profile should not be an obstacle to the use of the dolutegravir-based regimen now recommended in Brazil, but genotype testing may be warranted before initiating first-generation NNRTI-based regimens. [ABSTRACT FROM AUTHOR]

Bacillus thuringiensis INTA 7-3, INTA 51-3, INTA Mo9-5 and INTA Mo14-4 strains were obtained from Argentina and characterized by determination of serotype, toxicity, plasmid composition, insecticidal gene content (cry and vip) and the cloning of the single-vip3A gene of the INTA Mo9-5 strain. The serotype analysis identified the serovars tohokuensis and darmstadiensis for the INTA 51-3 and INTA Mo14-4 strains, respectively, whereas the INTA Mo9-5 strain was classified as “autoagglutinated”. In contrast to the plasmid patterns of INTA 7-3, INTA 51-3 and INTA Mo9-5 (which were similar to B. thuringiensis HD-1 strain), strain INTA Mo14-4 showed a unique plasmid array. PCR analysis of the four strains revealed the presence of cry genes and vip3A genes. Interestingly, it was found that B. thuringiensis 4Q7 strain, which is a plasmid cured strain, contained vip3A genes indicating the presence of these insecticidal genes in the chromosome. Bioassays towards various lepidopteran species revealed that B. thuringiensis INTA Mo9-5 and INTA 7-3 strains were highly active. In particular, the mean LC50 obtained against A. gemmatalis larvae with the INTA Mo9-5 and INTA 7-3 strains were 7 (5.7−8.6) and 6.7 (5.6-8.0) ppm, respectively. The INTA Mo14-4 strain was non-toxic and strain INTA 51-3 showed only a weak larvicidal activity. [ABSTRACT FROM AUTHOR]