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Rio Grande, Brazil

Escobar-Escamilla N.,Institute Diagnostico y Referencia Epidemiologicos InDRE | Ramirez-Gonzalez J.E.,Institute Diagnostico y Referencia Epidemiologicos InDRE | Gonzalez-Villa M.,Institute Diagnostico y Referencia Epidemiologicos InDRE | Torres-Mazadiego P.,Institute Diagnostico y Referencia Epidemiologicos InDRE | And 9 more authors.
Archives of Medical Research | Year: 2014

Background and Aims: Nontuberculous mycobacteria (NTM) are mainly distributed as important emerging pathogens in patients with chronic or immunosuppressive diseases. Accurate identification of causative species is crucial for proper treatment and patient follow-up. However, several difficulties are associated with phenotypic and molecular diagnostic methods for precise identification at the species level due to shared metabolic and genetic characteristics. We undertook this study to evaluate the application of the phylogenetic method based on hsp65 gene into Telenti's PCR-restriction enzyme analysis (PRA) for molecular identification of NTM. Methods: The study population was comprised of 1646 Mycobacterium clinical isolates (AFB positive) collected from 2008-2011, of which 537 (32.6%) were MNT identified by PRA analysis. DNA sequencing of hsp65 in 53 isolates (10%) was performed. Sequence identification through NCBI-Basic Local Alignment Search Tool (BLAST) achieved correct identification in 23 isolates. Phylogenetic trees including hsp65 available GenBank sequences for all described genres of NTM and hsp65 obtained sequences were constructed using Mega 5.05 software. We compared sequence identification based on phylogenetic clustering and BLAST similarity search. Results: Phylogenetic clustering allowed more specific differentiation of closely related species and clearer identification in comparison with BLAST; 30 Mycobacterium species (this is the first report of isolation of some of these from clinical samples in Mexico) were identified in this way. Conclusions: The proposed 440 bp hsp65 phylogenetic method allows a better identification tool to differentiate Mycobacterium species and is useful to complement diagnosis and epidemiological surveillance of NTM. © 2014 IMSS.

Aguilar N.,Catholic University of Peru | Valladares G.,Catholic University of Peru | Tanta J.,Laboratorio Of Micobacterias | Huaroto L.,Laboratorio Of Micobacterias | And 4 more authors.
IFMBE Proceedings | Year: 2013

Tuberculosis is one of the most deadly diseases according to the World Health Organization. In 2008, 1.1-1.7 million people died and 8.9-9.9 million new cases were regis-tered. Currently, the most important tool of diagnosis is the direct examination of sputum smears. Since early diagnosis is the main strategy to control tuberculosis, faster methods of diagnosis are required. In this paper, an algorithm to detect bacilli of tuberculosis in microscopic images of Ziehl-Neelsen-stained sputum smears is described. First, a database of 1,340 images was created. The algorithm considered three stages: segmentation, feature extraction and classification. The seg-mentation stage was based on color empirical rules. The fea-ture extraction stage considered: Fourier descriptors, Hu moments and Zernike moments. The classification stage was based on a support vector machine. The algorithm reached 41.24% sensitivity. An improvement of this algorithm could represent a tool to rapidly identify risky sputum smears. © 2013 Springer.

Carneiro P.F.,Federal University of Rio de Janeiro | Pinto M.D.C.F.R.,Federal University of Rio de Janeiro | Coelho T.S.,Laboratorio Of Micobacterias | Cavalcanti B.C.,Federal University of Ceara | And 11 more authors.
European Journal of Medicinal Chemistry | Year: 2011

Several quinonoid and phenazine compounds were synthesized in moderate to high yields and showed activity against H 37Rv, rifampicin and isoniazid-resistance strains of Mycobacterium tuberculosis. The cytotoxity of the compounds were evaluated against human peripheral blood mononuclear cells (PBMC) and these substances emerge as promising antitubercular prototypes. © 2011 Elsevier Masson SAS. All rights reserved.

Moura K.C.G.,Federal University of Rio de Janeiro | Carneiro P.F.,Federal University of Rio de Janeiro | Pinto M.D.C.F.R.,Federal University of Rio de Janeiro | Da Silva J.A.,Institute Quimica e Biotecnologia | And 8 more authors.
Bioorganic and Medicinal Chemistry | Year: 2012

Twenty-three naphthoimidazoles and six naphthoxazoles were synthesised and evaluated against susceptible and rifampicin- and isoniazid-resistant strains of Mycobacterium tuberculosis. Among all the compounds evaluated, fourteen presented MIC values in the range of 0.78 to 6.25 μg/mL against susceptible and resistant strains of M. tuberculosis. Five structures were solved by X-ray crystallographic analysis. These substances are promising antimycobacterial prototypes. © 2012 Elsevier Ltd. All rights reserved.

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