Navegando por Palavras-chave "molecular typing"
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- ItemSomente MetadadadosEnterobacterial repetitive intergenic consensus PCR is a useful tool for typing Mycobacterium chelonae and Mycobacterium abscessus isolates(Elsevier B.V., 2006-06-01) Sampaio, JLM; Viana-Niero, C.; De Freitas, D.; Hofling-Lima, A. L.; Leao, S. C.; Universidade Federal de São Paulo (UNIFESP); Inst Fleury Ensino & PesquisaOutbreaks of rapidly growing mycobacterium (RGM) infections are increasingly being reported worldwide. Information about genetic relatedness of isolates obtained during outbreaks can provide Opportunities for prompt intervention. Pulsed-field gel electrophoresis (PFGE) is expensive, time consuming, and labor intensive. Other than that, Mycobacterium abscessus isolates call suffer DNA degradation during electrophoresis. Polymerase chain reaction (PCR)-based methods are cheaper, faster, and easier to perform, but discriminatory power varies depending oil the primer used. Ill this study, we tested the competence of enterobacterial repetitive intergenic consensus (ERIC) PCR in comparison with PFGE to distinguish unrelated isolates (24 Mycobacterium chelonae and 24 M. abscessus) obtained front human and/or environmental samples and to group 56 isolates front 6 outbreaks confirmed epidemiologically, caused by M. chelonae and M abscessus after ophthalmologic refractive surgery and mesotherapy. Enterobacterial repetitive intergenic consensus PCR presented discriminatory power. calculated using Simpson's index of diversity, of 0.989 for M abscessus and 0.975 for M. chelonae and grouped outbreak isolates ill distinct groups showing epidemiologic concordance. Pulsed-field gel electrophoresis also grouped outbreak isolates and presented discriminatory power of 0.972 and 0.993 for M. abscessus and M. chelonae, respectively. DNA from 8 (22%) of 36 M. abscessus isolates analyzed showed degradation during electrophoresis. Compared with PFGE and epidemiologic information as the gold standard, ERIC PCR is a simple, high throughput, affordable, reproducible, and discriminatory molecular typing method for inference of genetic relatedness of RGMs of the M. chelonae-abscessus group. (c) 2006 Elsevier Inc. All rights reserved.
- 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.
- ItemSomente MetadadadosEvaluation of the prevalence and risk factors for colonization by vancomycin-resistant Enterococcus among patients on dialysis(Elsevier B.V., 2004-08-01) Barbosa, D.; Lima, L.; Silbert, S.; Sader, H.; Cendoroglo, M.; Draibe, S.; Camargo, L.; Vianna, L.; Belasco, A.; Sesso, R.; Universidade Federal de São Paulo (UNIFESP)Background Vancomycin-resistant Enterococcus (VRE) has been reported among long-term dialysis patients, although risk factors for VRE colonization are not well defined. This study alms to appraise the prevalence and risk factors for VRE colonization among patients on long-term dialysis therapy, as well as the mechanisms for dissemination of vancomycin resistance. Methods: This is a cross-sectional survey of 320 patients on long-term dialysis therapy at 2 hospitals of the Federal University of São Paulo from June 2001 to March 2003. Fecal samples were collected from each patient once a week for 1 month. Samples with positive test results for VRE were submitted to molecular typing through automated ribotyping. Results VRE prevalence was 14.4%. There were significant associations between VRE and dialysis type (hemodialysis, P = 0.04), number of hospitalizations (P = 0.03), low hemoglobin level (P = 0.03), and leukocytosis (P = 0.05). Among samples with VRE (n = 56), 25% were Enterococcus faecium; 10.7%, Enterococcus casseliflavus; 57.1%, Enterococcus grallinarum; and 3.6%, Enterococcus faecalis. All samples isolated were sensitive to telcoplanin, except for E faecium samples, which were strongly resistant, although 9 of 14 patients with this isolate presented the same ribogroup (111-S-4). Typing of 6 samples from 8 dialysis patients with Egallinarum was performed, showing a predominant ribogroup (112-S-4). Conclusion: Hospital environment, hemodialysis, anemia, and leukocytosis appear to be associated with VRE colonization. These results suggest that dissemination of these bacteria among patients on long-term dialysis therapy may be taking place.
- ItemSomente MetadadadosImproving typeability of multiple bacterial species using pulsed-field gel electrophoresis and thiourea(Elsevier B.V., 2003-12-01) Silbert, S.; Boyken, L.; Hollis, R. J.; Pfaller, M. A.; Universidade Federal de São Paulo (UNIFESP); Univ IowaAlthough pulsed-field gel electrophoresis is considered the gold standard technique for molecular typing, typeability may not be excellent for some bacterial species because of DNA degradation. Previous reports suggest that the addition of thiourea in the gel buffer can improved the typeability for some species. in the present study, 66 Gram-negative strains (seven species) known to be affected by DNA degradation and four control strains were evaluated by PFGE with and without the addition of 50 mug/M of thiourea to the buffer used in the electrophoresis. Macrorestriction patterns were obtained for all K. pneumoniae, S. marcescens, P. aeruginosa, and Salmonella spp., for 95.4% of E. coli, and for 50% of E. cloacae strains from the gels performed in the buffer with throurea. However, typeability was not improved for Acinetobacter spp. the range of non-typeable species for which thiourea can limit the problem of DNA degradation is considerably wider than described in previous publications. (C) 2003 Elsevier Inc. All rights reserved.
- ItemSomente MetadadadosTransposable elements and two other molecular markers as typing tools for the genus Paracoccidioides(Oxford Univ Press, 2015-02-01) Alves, Fernanda Lourenco; Ribeiro, Mariceli Araujo; Hahn, Rosane Christine; Teixeira, Marcus de Melo; Camargo, Zoilo Pires de [UNIFESP]; Cisalpino, Patricia Silva; Marini, Marjorie Mendes [UNIFESP]; Universidade Federal de Minas Gerais (UFMG); Univ Fed Espirito Santo; Univ Fed Mato Grosso; Universidade de Brasília (UnB); Universidade Federal de São Paulo (UNIFESP)Studies comparing Paracoccidioides brasiliensis and Paracoccidioides lutzii have shown that these fungi have significant genomic differences that may have implications in the clinical manifestation, diagnosis, and treatment of paracoccidioidomycosis caused by them. Thus, molecular typing methods are required that can distinguish between various species of Paracoccidioides. the aim of this study was to explore the potential use as molecular markers of the transposable elements Trem A-H recently identified and characterized in the genus Paracoccidioides as a means of differentiating the species. We take advantage of the abundance and distribution of these transposons in the Paracoccidioides genomes to develop a simple and highly reproducible polymerase chain reaction (PCR)-based technique. Furthermore we compare the performance of this test with two other molecular markers already in use to identify these fungi.
- ItemSomente MetadadadosTrypanosoma cruzi genome project: biological characteristics and molecular typing of clone CL Brener(Elsevier B.V., 1997-11-01) Zingales, B.; Pereira, MES; Oliveira, R. P.; Almeida, K. A.; Umezawa, E. S.; Souto, R. P.; Vargas, N.; Cano, M. I.; daSilveira, J. F.; Nehme, N. S.; Morel, C. M.; Brener, Z.; Macedo, A.; FIOCRUZ MS; Universidade Federal de Minas Gerais (UFMG); Universidade de São Paulo (USP); Universidade Federal de São Paulo (UNIFESP)Clone CL Brener is the reference organism used in the Trypanosoma cruzi Genome Project. CL Brener was obtained by cloning procedures from bloodstream trypomastigotes isolated from mice infected with the CL strain. the doubling time of CL Brener epimastigotes cultured at 28 degrees C in liver infusion-tryptose (LIT) medium is 58 +/- 13 h. Differentiation to metacyclic forms is induced by incubation of epimastigotes in LIT-20% Grace's medium. Metacyclics give very low parasitemia in mice, contrary to what is observed for blood forms which promote 100% mortality of the animals with inocula of 5 x 10(3) parasites. CL Brener blood forms are highly susceptible to nifurtimox, benznidazole and ketoconazole. Allopurinol is inefficient in the treatment of mice experimental infection. the clone infects mammalian cultured cells and performs the complete intracellular cycle at 33 and 37 degrees C. the molecular typing of CL Brener has been done by isoenzymatic profiles; sequencing of a 24S alpha ribosomal RNA gene domain and by schizodeme, randomly amplified polymorphic DNA and DNA fingerprinting analyses. for each typing approach the patterns obtained do not change after prolonged parasite subcultivation in LIT medium (up to 100 generations). the stability of the molecular karyotype of the clone was also confirmed. (C) 1997 Elsevier Science B.V.
- ItemAcesso aberto (Open Access)Typing of Enterococcus faecium by polymerase chain reaction and pulsed field gel electrophoresis(Associação Brasileira de Divulgação Científica, 2000-11-01) Bedendo, Joao [UNIFESP]; Pignatari, Antonio Carlos Campos [UNIFESP]; Universidade Estadual de Maringá Centro de Ciências da Saúde Departamento de Enfermagem; Universidade Federal de São Paulo (UNIFESP)Polymerase chain reaction (PCR) with JB1 or REP consensus oligonucleotides and pulsed field gel electrophoresis (PFGE) were used to study genomic DNA extracted from 31 strains of enterococci. Eleven ATCC strains, representative of 11 species of Enterococcus, were initially tested by JB1-PCR, revealing that Enterococcus malodoratus and Enterococcus hirae presented identical banding patterns. Eight Enterococcus faecium isolates from Stanford University and 12 from São Paulo Hospital were studied by JB1-PCR, REP-PCR 1/2R and PFGE. Among the isolates from Stanford University, 5 genotypes were defined by JB1-PCR, 7 by REP-PCR 1/2R and 4 by PFGE. Among the isolates from São Paulo Hospital, 9 genotypes were identified by JB1-PCR, 6 by REP-PCR and 5 by PFGE. The three methods identified identical genotypes, but there was not complete agreement among them.