Navegando por Palavras-chave "Mycobacterium"
Agora exibindo 1 - 11 de 11
Resultados por página
Opções de Ordenação
- ItemSomente MetadadadosAnálise molecular dos genes nid e cyp e avaliação da degradação de pireno por isolados de Mycobacterium sp(Universidade Federal de São Paulo, 2017-07-07) Silva, Natalia Maria da [UNIFESP]; Niero, Cristina Viana [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Polycyclic aromatic hydrocarbons (PAHs) are compounds found in the environment as a result of incomplete combustion of organic matter or the anthropogenic activity of exploration, refining and petroleum derivatives. They have complex structures with low solubility in water and remain for long periods in the environment being considered pollutants. Mycobacterium vanbaalenii-PYR1 was the first described microorganism with the ability to degrade pyrene, a polycyclic aromatic hydrocarbon. Sequencing of the genome of this strain revealed the presence of a region specialized in the degradation of HPA, called region A, containing genes encoding dioxygenase (nid). In addition, genes dispersed in the genome that encode monooxygenases (cyp150) with involvement in the degradation of these compounds have been described. Thus, this work investigated the presence of the nid and cyp genes in five Mycobacterium sp isolates by PCR and hybridizations with specific probes, besides the degradation of pyrene by phenotypic tests and by gas chromatography coupled to mass spectrometry (GC-MS). In the first stage of the work, the identification of the isolates was performed by the analysis of three essential genes by sequencing and the results obtained allowed to conclude that the isolates of this study are related to M. vanbaalenii and M. austroafricanum species. All isolates analyzed showed the ability to degrade pyrene by phenotypic tests. Gas chromatographic analyzes suggest that the MYC038, MYC040 and MYC211 isolates degrade 69.5%, 60.3% and 50.5% pyrene, respectively, over a period of 14 days. PCR results and hybridizations revealed the presence of only nidA and cyp150 genes in all isolates analyzed. The nidB, nidA3, nidB3 and ferredoxin phtAcAd genes were not identified in any of the isolates analyzed in this study suggesting their absence. Analyzes of the nidB2 gene did not allow to conclude its presence / absence. These data re-inforce the hypothesis of the present work that there is polymorphism in the A region of these isolates, and may also imply the existence of a new pathway for the degradation of aromatic hydrocarbons.
- ItemAcesso aberto (Open Access)Análise química e genômica de isolados dos gêneros Gordonia e Mycolicibacterium com capacidade de biotransformação de hidrocarbonetos(Universidade Federal de São Paulo, 2021-12-17) Silva, Natália Maria [UNIFESP]; Niero, Cristina Viana [UNIFESP]; http://lattes.cnpq.br/6723968833615135; http://lattes.cnpq.br/7929098887276347Os hidrocarbonetos são compostos químicos encontrados no meio ambiente, sendo provenientes da combustão incompleta da matéria orgânica e de atividades antropogênicas oriundas da exploração de petróleo, rejeitos de indústrias petroquímicas, postos de gasolina e acidentes ambientais. Além de serem recalcitrantes, alguns possuem efeitos carcinogênicos e mutagênicos, sendo considerados poluentes tóxicos e prejudiciais à saúde humana e ao meio ambiente. As actinobactérias são ubiquitárias e os gêneros Gordonia e Mycolicibacterium têm sido foco de estudos por possuírem relatos de isolados com potencial para degradação de compostos xenobióticos. Os clusters gênicos alk e CYP153 são descritos principalmente como responsáveis pela degradação de alcanos em diversos gêneros bacterianos. Já para a degradação microbiana de hidrocarbonetos aromáticos policíclicos (HPAs) ocorrem pela ação de múltiplos genes de dioxigenases (nid) localizados em uma ilha genômica também denominada região A. Deste modo, este trabalho investigou a degradação de n-hexadecano por cromatografia a gás acoplada a espectrometria de massas (CG-EM) e a presença de genes alk e CYP153 nos genomas de dois isolados do gênero Gordonia: G. paraffinivorans (MTZ052) e G. sihwensis (MTZ096). Investigou também a presença de genes envolvidos na degradação de HPAs nos genomas de cinco isolados de Mycolicibacterium austroafricanum, além da sua capacidade de degradação de pireno por CG-EM. O isolado MTZ052 apresentou apenas o cluster gênico CYP153 e uma taxa de degradação de n-hexadecano de 86%. Já o isolado MTZ096 apresentou em seu genoma os dois clusters gênicos (alk e CYP153) com uma taxa de degradação de 100%, indicando que a degradação de n-hexadecano foi mais efetiva pela ação dos dois sistemas. Os resultados de CG-EM mostraram que os isolados M. austroafricanum (MYC038 e MYC040) apresentaram degradação de 96% e 88% de pireno, respectivamente, em 7 dias de incubação. Interessantemente, as análises genômicas mostraram que estes isolados não possuem a ilha genômica contendo os genes descritos como degradadores de HPA.
- ItemAcesso aberto (Open Access)Discrimination of members of the Mycobacterium avium complex by polymerase chain reaction(Sociedade Brasileira de Microbiologia, 1999-04-01) Sircili, Marcelo Palma [UNIFESP]; Roxo, Eliana; Leao, Sylvia Cardoso [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Instituto BiológicoMycobacterium avium complex (MAC) species cannot be discriminated by the usual methods of biochemical identification of mycobacteria. This study showed that amplification by PCR of DT1 and DT6, two single copy sequences identified in the genome of M. avium serotype 2, the insertion sequence IS1245, found to be consistently present in M. avium strains and the heat-shock protein gene hsp65, followed by restriction polymorphism analysis, are rapid and accurate tests for the differentiation of the species M. avium, M. intracellulare, and M. scrofulaceum.
- ItemSomente MetadadadosEpidemic of surgical-site infections by a single clone of rapidly growing mycobacteria in Brazil(Future Medicine Ltd, 2010-06-01) Leao, Sylvia Cardoso [UNIFESP]; Viana-Niero, Cristina; Matsumoto, Cristianne Kayoko; Batista Lima, Karla Valeria; Lopes, Maria Luiza; Palaci, Moises; Hadad, David Jamil; Vinhas, Solange; Duarte, Rafael Silva; Silva Lourenco, Maria Cristina; Kipnis, Andre; das Neves, Zilah Candida; Alcantara Gabardo, Betina Mendez; Ribeiro, Marta Osorio; Baethgen, Ludmila; Assis, Denise Brandao de; Madalosso, Geraldine; Chimara, Erica; Dalcolmo, Margareth Pretti; Universidade Federal de São Paulo (UNIFESP); Univ Fed Espirito Santo; Inst Evandro Chagas; Universidade Federal do Rio de Janeiro (UFRJ); Fundacao Oswaldo Cruz; Universidade Federal de Goiás (UFG); Secretaria Municipal Saude Goiania; Secretaria Estadual Saude Parana; Lab Cent Saude Publ; Ctr Vigilancia Epidemiol Prof Alexandre Vranjac; Inst Adolfo Lutz Registro; Ctr Referencia Prof Helio FragaAim: Our aim is to investigate if the clusters of postsurgical mycobacterial infections, reported between 2004 and 2008 in seven geographically distant states in Brazil, were caused by a single mycobacterial strain. Materials & methods: Available information from 929 surgical patients was obtained from local health authorities. A total of 152 isolates from surgical patients were identified by PCR restriction enzyme analysis of the hsp65 gene (PRA-hsp65) and sequencing of the rpoB gene. Isolates were typed by pulsed-field gel electrophoresis (PFGE) using two restriction enzymes. Dral and Asel. A total of 15 isolates not related to surgical cases were analyzed for comparison. Results: All isolates were identified as Mycobacterium abscessus ssp. massiliense. Isolates from surgical patients and one sputum isolate grouped in a single PFGE cluster, composed of two closely related patterns, with one band difference. A total of 14 other isolates unrelated to surgical cases showed distinctive PFGE patterns. Conclusion: A particular strain of M. abscessus ssp. massiliense was associated with a prolonged epidemic of postsurgical infections in seven Brazilian states, suggesting that this strain may be distributed in Brazilian territory and better adapted to cause surgical-site infections.
- ItemAcesso aberto (Open Access)Estudo de isolados de Mycobacterium abscessus subsp. massiliense ambientais e de surto em modelo in vivo e ex vivo(Universidade Federal de São Paulo (UNIFESP), 2009-11-25) Serikawa, Janaina Mitie [UNIFESP]; Leao, Sylvia Cardoso [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)Micobacterias de crescimento rapido (MCR) tem sido frequentemente descritas em surtos de infeccoes em seres humanos. Mycobacterium abscessus subsp. massiliense e uma MCR que foi descrita pela primeira vez em 2004, e desde entao, 10 trabalhos identificando essa especie em surtos e casos clinicos esporadicos sao os relatos presentes na literatura. Assim, a interacao M. abscessus subsp. massiliense-hospedeiro foi o objetivo principal deste trabalho. Para isso, variantes de colonia lisa e rugosa de um isolado do surto que ocorreu em Belem, entre 2004 e 2005 (B7 L e R), e de 2 isolados nao relacionados a surtos (B67 (L) e MG3-6 (R)) foram utilizadas em infeccoes intraperitoneal e endovenosa de camundongos e ex vivo em macrofagos peritoneais e celulas epitelioides-like. No que tange a resposta imunologica apos a infeccao intraperitoneal, o nivel de citocinas foi semelhante para os 4 isolados. Entretanto, apos 14 dias da infeccao os bacos dos animais infectados pelos isolados B7 R e MG3-6 apresentavam um aumento significativo de peso em relacao aos demais grupos. Apos 90 dias, esta diferenca se manteve apenas para o grupo infectado com B7 R. A histologia dos bacos destes animais mostrou que a resposta proliferativa nos foliculos linfoides foi mais pronunciada para a infeccao por B7 R, levando a necrose central dos mesmos apos 14 dias. Nestes, bacilos alcool-acido resistentes foram encontrados penetrando a zona perifolicular, e tambem em vasos de maior calibre, sugerindo disseminacao via corrente sanguinea. A infeccao endovenosa corroborou os resultados obtidos para a infeccao intraperitoneal. Apos 2 dias de infeccao, a recuperacao de unidades formadoras de colonia (UFCs) do baco foi significativamente maior para os animais infectados por B7 R. Entretanto, a infeccao foi igualmente controlada em todos os grupos, semelhantemente a infeccao intraperitoneal. A infeccao de culturas de macrofagos e CEs-like corrobou os achados in vivo, pois B7 R foi capaz de se proliferar no interior de macrofagos e, apenas para este isolado, houve o aumento na porcentagem de CEs-like infectadas. Adicionalmente, o isolado B7 R estimulou uma producao menor de TGF-ƒÒ nas culturas quando comparado ao isolado de fenotipo liso. CEs-like nao foram capazes de conter a infeccao causada pelo isolado B7 R, talvez pela interacao micobacteria-CEs-like resultar em menor producao de TGF-£].Tomados em conjunto, os resultados apresentados sugerem que micobacterias formadoras de colonias rugosas associadas a surtos sao mais patogenicas que as de fenotipo liso e que aquelas presentes no ambiente. Os mecanismos subjacentes responsaveis por estes achados estao sendo estudados.
- ItemAcesso aberto (Open Access)hsp65 PCR-restriction enzyme analysis (PRA) for identification of mycobacteria in the clinical laboratory(Instituto de Medicina Tropical, 2001-02-01) Silva, Carolina Feher da [UNIFESP]; Ueki, Suely Yoko Mizuka; Geiger, Débora de Cássia Pires [UNIFESP]; Leao, Sylvia Cardoso [UNIFESP]; Universidade Federal de São Paulo (UNIFESP); Instituto Adolfo Lutz de São Paulo Setor de MicobactériasMore than 70 species of mycobacteria have been defined, and some can cause disease in humans, especially in immunocompromised patients. Species identification in most clinical laboratories is based on phenotypic characteristics and biochemical tests and final results are obtained only after two to four weeks. Quick identification methods, by reducing time for diagnosis, could expedite institution of specific treatment, increasing chances of success. PCR restriction-enzyme analysis (PRA) of the hsp65 gene was used as a rapid method for identification of 103 clinical isolates. Band patterns were interpreted by comparison with published tables and patterns available at an Internet site (http://www.hospvd.ch:8005). Concordant results of PRA and biochemical identification were obtained in 76 out of 83 isolates (91.5%). Results from 20 isolates could not be compared due to inconclusive PRA or biochemical identification. The results of this work showed that PRA could improve identification of mycobacteria in a routine setting because it is accurate, fast, and cheaper than conventional phenotypic identification.
- ItemAcesso aberto (Open Access)Identification of non-tuberculous mycobacteria from the Central Public Health Laboratory from Mato Grosso do Sul and analysis of clinical relevance(Sociedade Brasileira de Microbiologia, 2008-06-01) Moraes, Paulo Ricardo de Souza; Chimara, Erica [UNIFESP]; Telles, Maria Alice da Silva; Ueki, Suely Yoko Misuka; Cunha, Eunice Atsuko Totumi; Honer, Michael Robin; Leao, Sylvia Cardoso [UNIFESP]; Laboratório Central de Saúde Pública de Mato Grosso do Sul; Instituto Adolfo Lutz de São Paulo; Universidade Federal de Mato Grosso do Sul; Universidade Federal de São Paulo (UNIFESP)Non-tuberculous mycobacteria isolated at the Central Public Health Laboratory from Mato Grosso do Sul in 2003 and 2004 were identified by conventional phenotypic methods (TI) and by PCR-Restriction Enzyme Analysis (PRA) using the hsp65 gene as target (PRA-hsp65). With 15 of the 32 analysed isolates, results of both methods were concordant, being 8 Mycobacterium avium, 3 M. fortutium, 1 M. kansasii, 1 M. flavescens, 1 M. peregrinum and 1 Nocardia brasiliensis. TI of 12 isolates was inconclusive. Novel PRA-hsp65 patterns were observed with 11 isolates. Medical data were evaluated for inference of clinical relevance of these isolates.
- ItemSomente MetadadadosMicobactérias isoladas de pacientes portadores do vírus da imunodeficiência humana na grande São Paulo: aspectos microbiológicos, epidemiológicos, clínicos e laboratoriais(Universidade Federal de São Paulo (UNIFESP), 1994) Hadad, David Jamil [UNIFESP]; Castelo Filho, Adauto [UNIFESP]
- ItemSomente MetadadadosMulticenter evaluation of mycobacteria identification by PCR restriction enzyme analysis in laboratories from Latin America and the Caribbean(Elsevier B.V., 2005-05-01) Leao, S. C.; Bernardelli, A.; Cataldi, A.; Zumarraga, M.; Robledo, J.; Realpe, T.; Mejia, G. I.; Telles, MAD; Chimara, E.; Velazco, M.; Fernandez, J.; Rodrigues, P. A.; Guerrero, M. I.; Leon, C. I.; Porras, T. B.; Rastogi, N.; Goh, K. S.; Suffys, P.; Rocha, A. D.; Netto, D. D.; Ritacco, V; Lopez, B.; Barrera, L.; Palomino, J. C.; Martin, A.; Portaels, F.; Universidade Federal de São Paulo (UNIFESP); SENASA; INTA; Corp Invest Biol; Univ Pontificia Bolivariana; Inst Adolfo Lutz Registro; Inst Salud Publ Chile; Inst Nacl Salud; Inst Pasteur Guadeloupe; Fdn Oswaldo Cruz; Inst Nacl Enfermedades Infecciosas Carlos Malbran; Inst Trop MedThe identification of mycobacterial species in clinical isolates is essential for making patient care decisions. Polymerase chain reaction (PCR) restriction enzyme analysis (PRA) is a simple and rapid identification method, based on amplification of 441 bp of the hsp65 gene and restriction with BstEII and HaeIII. As a contribution to the validation of PRA, a multicenter study was performed in eight laboratories located in Argentina, Brazil, Colombia, Chile, and Guadeloupe. Each laboratory received 18 coded isolates from the collection of the Institute of Tropical Medicine (Antwerp, Belgium), representing duplicates of nine laboratory strains: Mycobacterium terrae CIPT 140320001, Mycobacterium scrofulaceum CIPT 140220031, Mycobacterium flavescens ATCC 14474, Mycobacterium triviale ATCC 23292, Mycobacterium nonchromogenicum ATCC 19530, Mycobacterium chitae ATCC 19627, Mycobacterium abscessus ATCC 19977, Mycobacterium kansasii ATCC 12478, and Mycobacterium peregrinum ATCC 14467. A detailed protocol including amplification, enzymatic digestion, and gel preparation was provided to each laboratory. Two laboratories identified correctly all 18 (100%) isolates, one identified correctly 17 (94.5%), two identified 14 (77.7%), one identified 11 (61%), and two identified 8 (44.4%) isolates. Errors detected in laboratories with more than 77% accuracy were associated with electrophoresis running conditions and an unspecific amplicon produced by a single strain. Lower accuracy was mainly related to inappropriate use of DNA markers and insufficient training in interpretation of patterns. in conclusion, the PRA method was readily implemented in some Latin American and Caribbean laboratories of mycobacteria, but improvements in critical points, as gel running conditions and training in interpretation of patterns, are needed in order to improve accuracy. in others, improvement in critical points is still necessary. (C) 2004 Elsevier B.V. All rights reserved.
- ItemAcesso aberto (Open Access)Mycobacterium tuberculosis expressing phospholipase C subverts PGE(2) synthesis and induces necrosis in alveolar macrophages(Biomed Central Ltd, 2014-05-19) Assis, Patricia A.; Espindola, Milena S.; Paula-Silva, Francisco W. G.; Rios, Wendy M.; Pereira, Priscilla A. T.; Leao, Sylvia Cardoso [UNIFESP]; Silva, Celio L.; Faccioli, Lucia H.; Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)Background: Phospholipases C (PLCs) are virulence factors found in several bacteria. in Mycobacterium tuberculosis (Mtb) they exhibit cytotoxic effects on macrophages, but the mechanisms involved in PLC-induced cell death are not fully understood. It has been reported that induction of cell necrosis by virulent Mtb is coordinated by subversion of PGE(2), an essential factor in cell membrane protection.Results: Using two Mtb clinical isolates carrying genetic variations in PLC genes, we show that the isolate 97-1505, which bears plcA and plcB genes, is more resistant to alveolar macrophage microbicidal activity than the isolate 97-1200, which has all PLC genes deleted. the isolate 97-1505 also induced higher rates of alveolar macrophage necrosis, and likewise inhibited COX-2 expression and PGE(2) production. To address the direct effect of mycobacterial PLC on cell necrosis and PGE(2) inhibition, both isolates were treated with PLC inhibitors prior to macrophage infection. Interestingly, inhibition of PLCs affected the ability of the isolate 97-1505 to induce necrosis, leading to cell death rates similar to those induced by the isolate 97-1200. Finally, PGE(2) production by Mtb 97-1505-infected macrophages was restored to levels similar to those produced by 97-1200-infected cells.Conclusions: Mycobacterium tuberculosis bearing PLCs genes induces alveolar macrophage necrosis, which is associated to subversion of PGE(2) production.
- ItemSomente MetadadadosPerformance de tres metodos na avaliacao da similaridade genetica de isolados do grupo Mycobacterium chelonae-abscessus(Universidade Federal de São Paulo (UNIFESP), 2005) Sampaio, Jorge Luiz Mello [UNIFESP]