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1.
Mem Inst Oswaldo Cruz ; 115: e200055, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401997

RESUMO

BACKGROUND Tuberculosis (TB) is an infectious disease caused by the bacterium Mycobacterium tuberculosis, and the number of new cases of multidrug resistant TB (MDR-TB), pre extensively drug-resistant TB (pre-XDR-TB) and extensively drug-resistant TB (XDR-TB) has increased considerably worldwide. OBJECTIVES Herein, using 156 M. tuberculosis isolates from 106 patients previously classified as MDR or pre-XDR or XDR isolates, we investigated the genetic mutation profiles associated with phenotypic resistances in patients with MDR-TB, pre-XDR-TB and XDR-TB, treatment outcomes and resistance evolution. METHODS Molecular analyses were performed by partial sequencing of the rpoB, katG, gyrA, gyrB, rrs genes and analysis of the fabG-inhA promoter region. Clinical, epidemiologic and demographic data were obtained from the TB Notification database system of São Paulo (TB-WEB) and the Information System for Special Tuberculosis Treatments (SITE-TB). FINDINGS Drug resistance was attributed to previously known mutations and a novel Asp449Val mutation in gyrB was observed in four isolates from the same patient. Ten patients had more than one isolate evaluated and eight of these patients displayed resistance progression. MAIN CONCLUSIONS The present study is the first to report the frequency of mutations related to second-line drug resistance in MDR-TB, pre-XDR-TB and XDR-TB isolates. The results could lead to the improvement of available technologies for the rapid detection of drug resistant TB.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Mutação/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adolescente , Adulto , Brasil , Tuberculose Extensivamente Resistente a Medicamentos/microbiologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Fatores Socioeconômicos , Adulto Jovem
2.
BMC Microbiol ; 17(1): 195, 2017 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-28903728

RESUMO

BACKGROUND: Outbreaks of infections caused by rapidly growing mycobacteria have been reported worldwide generally associated with medical procedures. Mycobacterium abscessus subsp. massiliense CRM0019 was obtained during an epidemic of postsurgical infections and was characterized by increased persistence in vivo. To better understand the successful survival strategies of this microorganism, we evaluated its infectivity and proliferation in macrophages (RAW and BMDM) and alveolar epithelial cells (A549). For that, we assessed the following parameters, for both M. abscessus CRM0019 as well as the reference strain M. abscessus ATCC 19977: internalization, intracellular survival for up 3 days, competence to subvert lysosome fusion and the intracellular survival after cell reinfection. RESULTS: CRM0019 and ATCC 19977 strains showed the same internalization rate (approximately 30% after 6 h infection), in both A549 and RAW cells. However, colony forming units data showed that CRM0019 survived better in A549 cells than the ATCC 19977 strain. Phagosomal characteristics of CRM0019 showed the bacteria inside tight phagosomes in A549 cells, contrasting to the loosely phagosomal membrane in macrophages. This observation holds for the ATCC 19977 strain in both cell types. The competence to subvert lysosome fusion was assessed by acidification and acquisition of lysosomal protein. For M. abscessus strains the phagosomes were acidified in all cell lines; nevertheless, the acquisition of lysosomal protein was reduced by CRM0019 compared to the ATCC 19977 strain, in A549 cells. Conversely, in macrophages, both M. abscessus strains were located in mature phagosomes, however without bacterial death. Once recovered from macrophages M. abscessus could establish a new intracellular infection. Nevertheless, only CRM0019 showed a higher growth rate in A549, increasing nearly 10-fold after 48 and 72 h. CONCLUSION: M. abscessus CRM0019 creates a protective and replicative niche in alveolar epithelial cells mainly by avoiding phagosome maturation. Once recovered from infected macrophages, CRM0019 remains infective and displays greater intracellular growth in A549 cells compared to the ATCC 19977 strain. This evasion strategy in alveolar epithelial cells may contribute to the long survival of the CRM0019 strain in the host and thus to the inefficacy of in vivo treatment.


Assuntos
Células Epiteliais Alveolares/microbiologia , Proliferação de Células , Interações Hospedeiro-Patógeno/fisiologia , Viabilidade Microbiana , Mycobacterium abscessus/fisiologia , Mycobacterium abscessus/patogenicidade , Células A549 , Animais , Contagem de Colônia Microbiana , Humanos , Evasão da Resposta Imune , Lisossomos/metabolismo , Macrófagos/microbiologia , Camundongos , Fagossomos/microbiologia , Células RAW 264.7
3.
BMC Microbiol ; 16(1): 111, 2016 06 17.
Artigo em Inglês | MEDLINE | ID: mdl-27316672

RESUMO

BACKGROUND: A large collection of sequenced mycobacteriophages capable of infecting a single host strain of Mycobacterium smegmatis shows considerable genomic diversity with dozens of distinctive types (clusters) and extensive variation within those sharing evident nucleotide sequence similarity. Here we profiled the mycobacterial components of a large composting system at the São Paulo zoo. RESULTS: We isolated and sequenced eight mycobacteriophages using Mycobacterium smegmatis mc(2)155 as a host. None of these eight phages infected any of mycobacterial strains isolated from the same materials. The phage isolates span considerable genomic diversity, including two phages (Barriga, Nhonho) related to Subcluster A1 phages, two Cluster B phages (Pops, Subcluster B1; Godines, Subcluster B2), three Subcluster F1 phages (Florinda, Girafales, and Quico), and Madruga, a relative of phage Patience with which it constitutes the new Cluster U. Interestingly, the two Subcluster A1 phages and the three Subcluster F1 phages have genomic relationships indicating relatively recent evolution within a geographically isolated niche in the composting system. CONCLUSIONS: We predict that composting systems such as those used to obtain these mycobacteriophages will be a rich source for the isolation of additional phages that will expand our view of bacteriophage diversity and evolution.


Assuntos
Micobacteriófagos/genética , Micobacteriófagos/isolamento & purificação , Mycobacterium/genética , Mycobacterium/virologia , Microbiologia do Solo , Solo , Bacteriófagos/genética , Sequência de Bases , Brasil , DNA Bacteriano/genética , DNA Viral/genética , Evolução Molecular , Genes Bacterianos , Variação Genética , Genoma Viral , Família Multigênica , Micobacteriófagos/classificação , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Mycobacterium smegmatis/classificação , Mycobacterium smegmatis/genética , Mycobacterium smegmatis/isolamento & purificação , Mycobacterium smegmatis/virologia , Filogenia
4.
Int J Syst Evol Microbiol ; 66(11): 4471-4479, 2016 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27499141

RESUMO

The taxonomic position of members of the Mycobacterium abscessus complex has been the subject of intensive investigation and, in some aspects confusion, in recent years as a result of varying approaches to genetic data interpretation. Currently, the former species Mycobacterium massiliense and Mycobacterium bolletii are grouped together as Mycobacterium abscessus subsp. bolletii. They differ greatly, however, as the former M. bolletii has a functional erm(41) gene that confers inducible resistance to macrolides, the primary therapeutic antimicrobials for M. abscessus, while in the former M. massiliense the erm(41) gene is non-functional. Furthermore, previous whole genome studies of the M. abscessus group support the separation of M. bolletii and M. massiliense. To shed further light on the population structure of Mycobacterium abscessus, 43 strains and three genomes retrieved from GenBank were subjected to pairwise comparisons using three computational approaches: verage ucleotide dentity, enome to enome istance and single nucleotide polymorphism analysis. The three methods produced overlapping results, each demonstrating three clusters of strains corresponding to the same number of taxonomic entities. The distances were insufficient to warrant distinction at the species level, but met the criteria for differentiation at the subspecies level. Based on prior erm(41)-related phenotypic data and current genomic data, we conclude that the species M. abscessus encompasses, in adjunct to the presently recognized subspecies M. abscessus subsp. abscessus and M. abscessus subsp. bolletii, a third subspecies for which we suggest the name M. abscessus subsp. massiliense comb. nov. (type strain CCUG 48898T=CIP 108297T=DSM 45103T=KCTC 19086T).


Assuntos
Mycobacterium/classificação , Filogenia , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Humanos , Mycobacterium/genética , Análise de Sequência de DNA
5.
Int J Syst Evol Microbiol ; 65(12): 4403-4409, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26358475

RESUMO

Five isolates of non-pigmented, rapidly growing mycobacteria were isolated from three patients and,in an earlier study, from zebrafish. Phenotypic and molecular tests confirmed that these isolates belong to the Mycobacterium chelonae-Mycobacterium abscessus group, but they could not be confidently assigned to any known species of this group. Phenotypic analysis and biochemical tests were not helpful for distinguishing these isolates from other members of the M. chelonae­M.abscessus group. The isolates presented higher drug resistance in comparison with other members of the group, showing susceptibility only to clarithromycin. The five isolates showed a unique PCR restriction analysis pattern of the hsp65 gene, 100 % similarity in 16S rRNA gene and hsp65 sequences and 1-2 nt differences in rpoB and internal transcribed spacer (ITS) sequences.Phylogenetic analysis of a concatenated dataset including 16S rRNA gene, hsp65, and rpoB sequences from type strains of more closely related species placed the five isolates together, as a distinct lineage from previously described species, suggesting a sister relationship to a group consisting of M. chelonae, Mycobacterium salmoniphilum, Mycobacterium franklinii and Mycobacterium immunogenum. DNA­DNA hybridization values .70 % confirmed that the five isolates belong to the same species, while values ,70 % between one of the isolates and the type strains of M. chelonae and M. abscessus confirmed that the isolates belong to a distinct species. The polyphasic characterization of these isolates, supported by DNA­DNA hybridization results,demonstrated that they share characteristics with M. chelonae­M. abscessus members, butconstitute a different species, for which the name Mycobacterium saopaulense sp. nov. is proposed. The type strain is EPM10906T (5CCUG 66554T5LMG 28586T5INCQS 0733T).


Assuntos
Mycobacterium/classificação , Filogenia , Animais , Técnicas de Tipagem Bacteriana , Composição de Bases , Brasil , Córnea/microbiologia , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Ácidos Graxos/química , Genes Bacterianos , Humanos , Dados de Sequência Molecular , Mycobacterium/genética , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/microbiologia , Mycobacterium chelonae , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Peixe-Zebra/microbiologia
6.
Int J Syst Evol Microbiol ; 65(7): 2148-2153, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25858242

RESUMO

Two isolates from water, D16Q19 and D16R27, were shown to be highly similar in their 16S rRNA, 16S-23S internal transcribed spacer (ITS), hsp65 and rpoB gene sequences to 'Mycobacterium franklinii' DSM 45524, described in 2011 but with the name not validly published. They are all nonpigmented rapid growers and are related phenotypically and genetically to the Mycobacterium chelonae-Mycobacterium abscessus group. Extensive characterization by phenotypic analysis, biochemical tests, drug susceptibility testing, PCR restriction enzyme analysis of the hsp65 gene and ITS, DNA sequencing of housekeeping genes and DNA-DNA hybridization demonstrated that 'M. franklinii' DSM 45524, D16Q19 and D16R27 belong to a single species that is separated from other members of the M. chelonae-M. abscessus group. On the basis of these results we propose the formal recognition of Mycobacterium franklinii sp. nov. Strain DSM 45524(T) ( = ATCC BAA-2149(T)) is the type strain.


Assuntos
Mycobacterium/classificação , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , DNA Espaçador Ribossômico/genética , Genes Bacterianos , Dados de Sequência Molecular , Mycobacterium/genética , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
7.
J Clin Microbiol ; 52(5): 1727-9, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24574286

RESUMO

Plasmid-mediated kanamycin resistance was detected in a strain of Mycobacterium abscessus subsp. bolletii responsible for a nationwide epidemic of surgical infections in Brazil. The plasmid did not influence susceptibility to tobramycin, streptomycin, trimethoprim-sulfamethoxazole, clarithromycin, or ciprofloxacin. Plasmid-mediated drug resistance has not been described so far in mycobacteria.


Assuntos
Resistência a Medicamentos/genética , Infecções por Mycobacterium/microbiologia , Mycobacterium/genética , Plasmídeos/genética , Antibacterianos/farmacologia , Técnicas de Tipagem Bacteriana/métodos , Brasil , DNA Bacteriano/genética , Humanos , Testes de Sensibilidade Microbiana/métodos , Mycobacterium/efeitos dos fármacos , Infecções por Mycobacterium/tratamento farmacológico
8.
J Clin Microbiol ; 52(8): 2881-91, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24899019

RESUMO

Outbreaks of infections by rapidly growing mycobacteria following invasive procedures, such as ophthalmological, laparoscopic, arthroscopic, plastic, and cardiac surgeries, mesotherapy, and vaccination, have been detected in Brazil since 1998. Members of the Mycobacterium chelonae-Mycobacterium abscessus group have caused most of these outbreaks. As part of an epidemiological investigation, the isolates were typed by pulsed-field gel electrophoresis (PFGE). In this project, we performed a large-scale comparison of PFGE profiles with the results of a recently developed multilocus sequence typing (MLST) scheme for M. abscessus. Ninety-three isolates were analyzed, with 40 M. abscessus subsp. abscessus isolates, 47 M. abscessus subsp. bolletii isolates, and six isolates with no assigned subspecies. Forty-five isolates were obtained during five outbreaks, and 48 were sporadic isolates that were not associated with outbreaks. For MLST, seven housekeeping genes (argH, cya, glpK, gnd, murC, pta, and purH) were sequenced, and each isolate was assigned a sequence type (ST) from the combination of obtained alleles. The PFGE patterns of DraI-digested DNA were compared with the MLST results. All isolates were analyzable by both methods. Isolates from monoclonal outbreaks showed unique STs and indistinguishable or very similar PFGE patterns. Thirty-three STs and 49 unique PFGE patterns were identified among the 93 isolates. The Simpson's index of diversity values for MLST and PFGE were 0.69 and 0.93, respectively, for M. abscessus subsp. abscessus and 0.96 and 0.97, respectively, for M. abscessus subsp. bolletii. In conclusion, the MLST scheme showed 100% typeability and grouped monoclonal outbreak isolates in agreement with PFGE, but it was less discriminative than PFGE for M. abscessus.


Assuntos
Eletroforese em Gel de Campo Pulsado/métodos , Tipagem de Sequências Multilocus/métodos , Micobactérias não Tuberculosas/classificação , Micobactérias não Tuberculosas/genética , Brasil/epidemiologia , Surtos de Doenças , Humanos , Epidemiologia Molecular/métodos , Infecções por Mycobacterium não Tuberculosas/epidemiologia
9.
J Clin Microbiol ; 52(8): 2990-7, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24920766

RESUMO

Worldwide, nontuberculous mycobacteria (NTM) have become emergent pathogens of pulmonary infections in cystic fibrosis (CF) patients, with an estimated prevalence ranging from 5 to 20%. This work investigated the presence of NTM in sputum samples of 129 CF patients (2 to 18 years old) submitted to longitudinal clinical supervision at a regional reference center in Rio de Janeiro, Brazil. From June 2009 to March 2012, 36 NTM isolates recovered from 10 (7.75%) out of 129 children were obtained. Molecular identification of NTM was performed by using PCR restriction analysis targeting the hsp65 gene (PRA-hsp65) and sequencing of the rpoB gene, and susceptibility tests were performed that followed Clinical and Laboratory Standards Institute recommendations. For evaluating the genotypic diversity, pulsed-field gel electrophoresis (PFGE) and/or enterobacterial repetitive intergenic consensus sequence PCR (ERIC-PCR) was performed. The species identified were Mycobacterium abscessus subsp. bolletii (n = 24), M. abscessus subsp. abscessus (n = 6), Mycobacterium fortuitum (n = 3), Mycobacterium marseillense (n = 2), and Mycobacterium timonense (n = 1). Most of the isolates presented resistance to five or more of the antimicrobials tested. Typing profiles were mainly patient specific. The PFGE profiles indicated the presence of two clonal groups for M. abscessus subsp. abscessus and five clonal groups for M. abscesssus subsp. bolletii, with just one clone detected in two patients. Given the observed multidrug resistance patterns and the possibility of transmission between patients, we suggest the implementation of continuous and routine investigation of NTM infection or colonization in CF patients, including countries with a high burden of tuberculosis disease.


Assuntos
Fibrose Cística/complicações , Farmacorresistência Bacteriana Múltipla , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/efeitos dos fármacos , Adolescente , Anti-Infecciosos/farmacologia , Proteínas de Bactérias/genética , Brasil , Chaperonina 60/genética , Criança , Pré-Escolar , RNA Polimerases Dirigidas por DNA/genética , Eletroforese em Gel de Campo Pulsado , Variação Genética , Genótipo , Humanos , Masculino , Tipagem Molecular , Micobactérias não Tuberculosas/classificação , Micobactérias não Tuberculosas/genética , Micobactérias não Tuberculosas/isolamento & purificação , Reação em Cadeia da Polimerase , Polimorfismo de Fragmento de Restrição , Escarro/microbiologia
10.
BMC Microbiol ; 14: 128, 2014 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-24886263

RESUMO

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 PGE2, 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 PGE2 production. To address the direct effect of mycobacterial PLC on cell necrosis and PGE2 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, PGE2 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 PGE2 production.


Assuntos
Morte Celular , Dinoprostona/antagonistas & inibidores , Macrófagos Alveolares/microbiologia , Macrófagos Alveolares/fisiologia , Mycobacterium tuberculosis/enzimologia , Fosfolipases Tipo C/metabolismo , Fatores de Virulência/metabolismo , Proteínas de Bactérias/genética , Humanos , Mycobacterium tuberculosis/imunologia , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/microbiologia , Fosfolipases Tipo C/genética
11.
Front Microbiol ; 15: 1335985, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38322314

RESUMO

Five mycobacterial isolates from sewage were classified as members of the genus Mycobacterium but presented inconclusive species assignments. Thus, the isolates (MYC017, MYC098, MYC101, MYC123 and MYC340) were analyzed by phenotypical, biochemical, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and genomic features to clarify their taxonomic position. Phenotypic analysis and biochemical tests did not distinguish these isolates from other non-pigmented mycobacteria. In contrast, MALDI-TOF MS analysis showed that isolates were not related to any previously described Mycobacterium species. Comparative genomic analysis showed values of ANI and dDDH between 81.59-85.56% and 24.4-28.8%, respectively, when compared to the genomes of species of this genus. In addition, two (MYC101 and MYC123) presented indistinguishable protein spectra from each other and values of ANI = 98.57% and dDDH = 97.3%, therefore being considered as belonging to the same species. Phylogenetic analysis grouped the five isolates within the Mycobacterium terrae complex (MTC) but in a specific subclade and separated from the species already described and supported by 100% bootstrap value, confirming that they are part of this complex but different from earlier described species. According to these data, we propose the description of four new species belonging to the Mycobacterium genus: (i) Mycobacterium defluvii sp. nov. strain MYC017T (= ATCC TSD-296T = JCM 35364T), (ii) Mycobacterium crassicus sp. nov. strain MYC098T (= ATCC TSD-297T = JCM 35365T), (iii) Mycobacterium zoologicum sp. nov. strain MYC101T (= ATCC TSD-298T = JCM 35366T) and MYC123 (= ATCC BAA-3216 = JCM 35367); and (iv) Mycobacterium nativiensis sp. nov. strain MYC340T (= ATCC TSD-299T = JCM 35368T).

12.
Eur Respir J ; 42(6): 1604-13, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23598956

RESUMO

A significant knowledge gap exists concerning the geographical distribution of nontuberculous mycobacteria (NTM) isolation worldwide. To provide a snapshot of NTM species distribution, global partners in the NTM-Network European Trials Group (NET) framework (www.ntm-net.org), a branch of the Tuberculosis Network European Trials Group (TB-NET), provided identification results of the total number of patients in 2008 in whom NTM were isolated from pulmonary samples. From these data, we visualised the relative distribution of the different NTM found per continent and per country. We received species identification data for 20 182 patients, from 62 laboratories in 30 countries across six continents. 91 different NTM species were isolated. Mycobacterium avium complex (MAC) bacteria predominated in most countries, followed by M. gordonae and M. xenopi. Important differences in geographical distribution of MAC species as well as M. xenopi, M. kansasii and rapid-growing mycobacteria were observed. This snapshot demonstrates that the species distribution among NTM isolates from pulmonary specimens in the year 2008 differed by continent and differed by country within these continents. These differences in species distribution may partly determine the frequency and manifestations of pulmonary NTM disease in each geographical location.


Assuntos
Pneumopatias/microbiologia , Pulmão/microbiologia , Infecções por Mycobacterium não Tuberculosas/microbiologia , Micobactérias não Tuberculosas/genética , Geografia , Saúde Global , Humanos , Pneumopatias/epidemiologia , Infecções por Mycobacterium não Tuberculosas/epidemiologia , Mycobacterium avium , Mycobacterium kansasii , Mycobacterium xenopi , Especificidade da Espécie
14.
Microorganisms ; 11(6)2023 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-37374915

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are chemical compounds that are widespread in the environment, arising from the incomplete combustion of organic material, as well as from human activities involving petrol exploitation, petrochemical industrial waste, gas stations, and environmental disasters. PAHs of high molecular weight, such as pyrene, have carcinogenic and mutagenic effects and are considered pollutants. The microbial degradation of PAHs occurs through the action of multiple dioxygenase genes (nid), which are localized in genomic island denominate region A, and cytochrome P450 monooxygenases genes (cyp) dispersed in the bacterial genome. This study evaluated pyrene degradation by five isolates of Mycolicibacterium austroafricanum using 2,6-dichlorophenol indophenol (DCPIP assay), gas chromatography/mass spectrometry (CG/MS), and genomic analyses. Two isolates (MYC038 and MYC040) exhibited pyrene degradation indexes of 96% and 88%, respectively, over a seven-day incubation period. Interestingly, the genomic analyses showed that the isolates do not have nid genes, which are involved in PAH biodegradation, despite their ability to degrade pyrene, suggesting that degradation may occur due to the presence of cyp150 genes, or even genes that have not yet been described. To the best of our knowledge, this is the first report of isolates without nid genes demonstrating the ability to degrade pyrene.

15.
Mem Inst Oswaldo Cruz ; 107(8): 969-77, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23295745

RESUMO

A single strain of Mycobacterium abscessus subsp. bolletii, characterised by a particular rpoB sequevar and two highly related pulsed field gel electrophoresis patterns has been responsible for a nationwide outbreak of surgical infections in Brazil since 2004. In this study, we developed molecular tests based on polymerase chain reaction restriction-enzyme analysis (PRA) and sequencing for the rapid identification of this strain. Sequences of 15 DNA regions conserved in mycobacteria were retrieved from GenBank or sequenced and analysed in silico. Single nucleotide polymorphisms specific to the epidemic strain and located in enzyme recognition sites were detected in rpoB, the 3' region of the 16S rDNA and gyrB. The three tests that were developed, i.e., PRA-rpoB, PRA-16S and gyrB sequence analysis, showed 100%, 100% and 92.31% sensitivity and 93.06%, 90.28% and 100% specificity, respectively, for the discrimination of the surgical strain from other M. abscessus subsp. bolletii isolates, including 116 isolates from 95 patients, one environmental isolate and two type strains. The results of the three tests were stable, as shown by results obtained for different isolates from the same patient. In conclusion, due to the clinical and epidemiological importance of this strain, these tests could be implemented in reference laboratories for the rapid preliminary diagnosis and epidemiological surveillance of this epidemic strain.


Assuntos
Infecções por Mycobacterium/microbiologia , Mycobacterium/genética , Infecção da Ferida Cirúrgica/microbiologia , Técnicas de Tipagem Bacteriana/métodos , Sequência de Bases , Brasil , DNA Bacteriano/análise , DNA Ribossômico/análise , Eletroforese em Gel de Campo Pulsado , Humanos , Mycobacterium/classificação , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/epidemiologia , Análise de Sequência de DNA , Infecção da Ferida Cirúrgica/epidemiologia
16.
J Voice ; 2022 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-35000836

RESUMO

INTRODUCTION: In recent years cepstral analysis and specific cepstrum-based measures such as smoothed cepstral peak prominence (CPPS) has become increasingly researched and utilized in attempts to determine the extent of overall dysphonia in voice signals. Yet, few studies have extensively examined how specific voice-source parameters affect CPPS values. OBJECTIVE: Using a range of synthesized tones, this exploratory study sought to systematically analyze the effect of fundamental frequency (fo), vibrato extent, source-spectrum tilt, and the amplitude of the voice-source fundamental on CPPS values. MATERIALS AND METHODS: A series of scales were synthesised using the freeware Madde. Fundamental frequency, vibrato extent, source-spectrum tilt, and the amplitude of the voice-source fundamental were systematically and independently varied. The tones were analysed in PRAAT, and statistical analyses were conducted in SPSS. RESULTS: CPPS was significantly affected by both fo and source-spectrum tilt, independently. A nonlinear association was seen between vibrato extent and CPPS, where CPPS values increased from 0 to 0.6 semitones (ST), then rapidly decreased approaching 1.0 ST. No relationship was seen between the amplitude of the voice-source fundamental and CPPS. CONCLUSION: The large effect of fo should be taken into account when analyzing the voice, particularly in singing-voice research, when comparing pre and posttreatment data, and when comparing inter-subject CPPS data.

17.
J Clin Microbiol ; 49(1): 62-8, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21084521

RESUMO

An epidemic of infections by rapidly growing mycobacteria related to surgical procedures between 2004 and 2008 in Brazil was caused by a unique strain showing the Mycobacterium abscessus type 2 pattern when it was analyzed by the molecular method of PCR-restriction enzyme analysis of the hsp65 gene (PRA-hsp65). In order to investigate the diversity of M. abscessus type 2 clinical isolates and to assess whether this epidemic strain was present in specimens from nonsurgical patients, we studied 52 isolates from 38 patients showing this characteristic PRA-hsp65 pattern obtained between 2005 and 2009. All isolates were identified by sequencing of region V of the rpoB gene and typed by pulsed-field gel electrophoresis (PFGE) using two restriction enzymes, DraI and AseI. Seven isolates obtained from sputum, bronchoalveolar lavage fluid, and urine in three different Brazilian states showed rpoB sequences 100% similar to the rpoB sequence of epidemic strain INCQS 594 and PFGE patterns highly related to the patterns of isolates, evidencing the presence of the epidemic strain in isolates from patients not associated with the surgical epidemic. The remaining isolates showed diverse rpoB sequences, with the highest similarities being to the corresponding sequences of M. massiliense(T) CIP 108297 (21 isolates), M. bolletii(T) CIP 108541 (19 isolates), or M. abscessus(T) ATCC 19977 (5 isolates). Two additional clusters could be detected by PFGE. PFGE showed 100% typeability and reproducibility and discriminatory powers, calculated by Simpson's index of diversity, of 0.978 (DraI) and 0.986 (AseI), confirming its suitability for the discrimination of M. abscessus type 2 isolates.


Assuntos
Variação Genética , Tipagem Molecular , Infecções por Mycobacterium/microbiologia , Mycobacterium/classificação , Mycobacterium/genética , Adulto , Idoso , Proteínas de Bactérias/genética , Brasil , Líquido da Lavagem Broncoalveolar/microbiologia , Chaperonina 60/genética , Análise por Conglomerados , RNA Polimerases Dirigidas por DNA/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Mycobacterium/isolamento & purificação , Análise de Sequência de DNA , Escarro/microbiologia , Urina/microbiologia
18.
J Clin Microbiol ; 49(2): 491-9, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21106786

RESUMO

Mycobacterium abscessus, Mycobacterium bolletii, and Mycobacterium massiliense (Mycobacterium abscessus sensu lato) are closely related species that currently are identified by the sequencing of the rpoB gene. However, recent studies show that rpoB sequencing alone is insufficient to discriminate between these species, and some authors have questioned their current taxonomic classification. We studied here a large collection of M. abscessus (sensu lato) strains by partial rpoB sequencing (752 bp) and multilocus sequence analysis (MLSA). The final MLSA scheme developed was based on the partial sequences of eight housekeeping genes: argH, cya, glpK, gnd, murC, pgm, pta, and purH. The strains studied included the three type strains (M. abscessus CIP 104536(T), M. massiliense CIP 108297(T), and M. bolletii CIP 108541(T)) and 120 isolates recovered between 1997 and 2007 in France, Germany, Switzerland, and Brazil. The rpoB phylogenetic tree confirmed the existence of three main clusters, each comprising the type strain of one species. However, divergence values between the M. massiliense and M. bolletii clusters all were below 3% and between the M. abscessus and M. massiliense clusters were from 2.66 to 3.59%. The tree produced using the concatenated MLSA gene sequences (4,071 bp) also showed three main clusters, each comprising the type strain of one species. The M. abscessus cluster had a bootstrap value of 100% and was mostly compact. Bootstrap values for the M. massiliense and M. bolletii branches were much lower (71 and 61%, respectively), with the M. massiliense cluster having a fuzzy aspect. Mean (range) divergence values were 2.17% (1.13 to 2.58%) between the M. abscessus and M. massiliense clusters, 2.37% (1.5 to 2.85%) between the M. abscessus and M. bolletii clusters, and 2.28% (0.86 to 2.68%) between the M. massiliense and M. bolletii clusters. Adding the rpoB sequence to the MLSA-concatenated sequence (total sequence, 4,823 bp) had little effect on the clustering of strains. We found 10/120 (8.3%) isolates for which the concatenated MLSA gene sequence and rpoB sequence were discordant (e.g., M. massiliense MLSA sequence and M. abscessus rpoB sequence), suggesting the intergroup lateral transfers of rpoB. In conclusion, our study strongly supports the recent proposal that M. abscessus, M. massiliense, and M. bolletii should constitute a single species. Our findings also indicate that there has been a horizontal transfer of rpoB sequences between these subgroups, precluding the use of rpoB sequencing alone for the accurate identification of the two proposed M. abscessus subspecies.


Assuntos
Técnicas de Tipagem Bacteriana , RNA Polimerases Dirigidas por DNA/genética , Tipagem de Sequências Multilocus , Mycobacterium/classificação , Mycobacterium/genética , Proteínas de Bactérias/genética , Brasil , Análise por Conglomerados , DNA Bacteriano/química , DNA Bacteriano/genética , França , Alemanha , Humanos , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Suíça
19.
Int J Syst Evol Microbiol ; 61(Pt 9): 2311-2313, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21037035

RESUMO

The names 'Mycobacterium abscessus subsp. abscessus' and 'Mycobacterium abscessus subsp. massiliense', proposed by Leao et al. (2009, J Clin Microbiol 47, 2691-2698), cannot be validly published. The purpose of this report is to provide a description in accordance with the Rules of the Bacteriological Code (1990 Revision). Moreover, the proposal of the name 'Mycobacterium abscessus subsp. massiliense' is contrary to Rule 38 and the correct name of this taxon, at the rank of subspecies, is Mycobacterium abscessus subsp. bolletii comb. nov. A description of Mycobacterium abscessus subsp. abscessus subsp. nov. and an emended description of Mycobacterium abscessus are also given.


Assuntos
Mycobacterium/classificação , Mycobacterium/genética , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Mycobacterium/fisiologia , Terminologia como Assunto
20.
Folia Phoniatr Logop ; 63(6): 305-11, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21625144

RESUMO

AIM: To identify the discriminative characteristics of the phonatory deviation diagram (PDD) in rough, breathy and tense voices. METHODS: One hundred and ninety-six samples of normal and dysphonic voices from adults were submitted to perceptual auditory evaluation, focusing on the predominant vocal quality and the degree of deviation. Acoustic analysis was performed with the VoxMetria (CTS Informatica). RESULTS: Significant differences were observed between the dysphonic and normal groups (p < 0.001), and also between the breathy and rough samples (p = 0.044) and the breathy and tense samples (p < 0.001). All normal voices were positioned in the inferior left quadrant, 45% of the rough voices in the inferior right quadrant, 52.6% of the breathy voices in the superior right quadrant and 54.3% of the tense voices in the inferior left quadrant of the PDD. In the inferior left quadrant, 93.8% of voices with no deviation were located and 72.7% of voices with mild deviation; voices with moderate deviation were distributed in the inferior and superior right quadrants, the latter ones containing the most deviant voices and 80% of voices with severe deviation. CONCLUSION: The PDD was able to discriminate normal from dysphonic voices, and the distribution was related to the type and degree of voice alteration.


Assuntos
Disfonia/diagnóstico , Fonação , Índice de Gravidade de Doença , Acústica da Fala , Qualidade da Voz , Adulto , Percepção Auditiva , Apresentação de Dados , Disfonia/fisiopatologia , Feminino , Humanos , Masculino
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