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1.
Mem Inst Oswaldo Cruz ; 115: e200520, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33533871

RESUMO

BACKGROUND: The evaluation of procedures for drug susceptibility prediction of Mycobacterium tuberculosis based on genomic data against the conventional reference method test based on culture is realistic considering the scenario of growing number of tools proposals based on whole-genome sequences (WGS). OBJECTIVES: This study aimed to evaluate drug susceptibility testing (DST) outcome based on WGS tools and the phenotypic methods performed on isolates of M. tuberculosis Lineage 1 from the state of Pará, Brazil, generally associated with low levels of drug resistance. METHODOLOGY: Culture based DST was performed using the Proportion Method in Löwenstein-Jensen medium on 71 isolates that had been submitted to WGS. We analysed the seven main genome sequence-based tools for resistance and lineage prediction applied to M. tuberculosis and for comparison evaluation we have used the Kappa concordance test. FINDINGS: When comparing the WGS-based tools against the DST, we observed the highest level of agreement using TB-profiler. Among the tools, TB-profiler, KvarQ and Mykrobe were those which identified the largest number of TB-MDR cases. Comparing the four most sensitive tools regarding resistance prediction, agreement was observed for 43 genomes. MAIN CONCLUSIONS: Drug resistance profiling using next-generation sequencing offers rapid assessment of resistance-associated mutations, therefore facilitating rapid access to effective treatment.


Assuntos
Antituberculosos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/genética , Antituberculosos/uso terapêutico , Brasil , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/isolamento & purificação , Preparações Farmacêuticas , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Sequenciamento Completo do Genoma
2.
Mem Inst Oswaldo Cruz ; 116: e200517, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33729319

RESUMO

Molecular-typing can help in unraveling epidemiological scenarios and improvement for disease control strategies. A literature review of Mycobacterium tuberculosis transmission in Brazil through genotyping on 56 studies published from 1996-2019 was performed. The clustering rate for mycobacterial interspersed repetitive units - variable tandem repeats (MIRU-VNTR) of 1,613 isolates were: 73%, 33% and 28% based on 12, 15 and 24-loci, respectively; while for RFLP-IS6110 were: 84% among prison population in Rio de Janeiro, 69% among multidrug-resistant isolates in Rio Grande do Sul, and 56.2% in general population in São Paulo. These findings could improve tuberculosis (TB) surveillance and set up a solid basis to build a database of Mycobacterium genomes.


Assuntos
Repetições Minissatélites/genética , Mycobacterium tuberculosis/genética , Polimorfismo de Fragmento de Restrição/genética , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Genótipo , Humanos , Epidemiologia Molecular , Mycobacterium tuberculosis/isolamento & purificação , Sequenciamento Completo do Genoma
3.
Mem Inst Oswaldo Cruz ; 115: e190401, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32401897

RESUMO

Bacillus Calmette Guerin (BCG) vaccines comprise a family of related strains. Whole genome sequencing has allowed the better characterisation of the differences between many of the BCG vaccines. As sequencing technologies improve, updating of publicly available sequence data becomes common practice. We hereby announce the draft genome of four commonly used BCG vaccines in Brazil, Argentina and Venezuela.


Assuntos
Vacina BCG/genética , Mapeamento Cromossômico , Mycobacterium bovis/genética , Argentina , Sequência de Bases , Brasil , Humanos , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único , Venezuela
4.
Microbiology (Reading) ; 163(2): 109-121, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28270262

RESUMO

The phylum Actinobacteria, which comprises a great variety of Gram-positive bacteria with a high G+C content in their genomes, is known for its large production of bioactive compounds, including those with antimicrobial activity. Among the antimicrobials, bacteriocins, ribosomally synthesized peptides, represent an important arsenal of potential new drugs to face the increasing prevalence of resistance to antibiotics among microbial pathogens. The actinobacterial bacteriocins form a heterogeneous group of substances that is difficult to adapt to most proposed classification schemes. However, recent updates have accommodated efficiently the diversity of bacteriocins produced by this phylum. Among the bacteriocins, the lantibiotics represent a source of new antimicrobials to control infections caused mainly by Gram-positive bacteria and with a low propensity for resistance development. Moreover, some of these compounds have additional biological properties, exhibiting activity against viruses and tumour cells and having also potential to be used in blood pressure or inflammation control and in pain relief. Thus, lantibiotics already described in Actinobacteria exhibit potential practical applications in medical settings, food industry and agriculture, with examples at different stages of pre-clinical and clinical trials.


Assuntos
Actinobacteria/efeitos dos fármacos , Actinobacteria/metabolismo , Antibacterianos/farmacologia , Infecções Bacterianas/tratamento farmacológico , Bacteriocinas/biossíntese , Antibacterianos/biossíntese , Bacteriocinas/farmacologia , Testes de Sensibilidade Microbiana
5.
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
6.
Gastrointest Endosc ; 83(5): 944-53, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26408426

RESUMO

BACKGROUND AND AIMS: Attention to patient safety has increased recently due to outbreaks of nosocomial infections associated with GI endoscopy. The aim of this study was to evaluate current cleaning and disinfection procedures of endoscope channels with high bioburden and biofilm analysis, including the use of resistant mycobacteria associated with postsurgical infections in Brazil. METHODS: Twenty-seven original endoscope channels were contaminated with organic soil containing 10(8) colony-forming units/mL of Pseudomonas aeruginosa, Staphylococcus aureus, or Mycobacterium abscessus subsp bolletii. Biofilms with the same microorganisms were developed on the inner surface of channels with the initial inoculum of 10(5) colony-forming units/mL. Channels were reprocessed following current protocol, and samples from cleaning and disinfection steps were analyzed by bioluminescence for adenosine triphosphate, cultures for viable microorganisms, and confocal microscopy. RESULTS: After contamination, adenosine triphosphate levels increased dramatically, and high bacterial growth was observed in all cultures. After cleaning, adenosine triphosphate levels decreased to values comparable to precontamination levels, and bacterial growth was demonstrated in 5 of 27 catheters, 2 with P aeruginosa and 3 with M abscessus. With regard to induced biofilm, a remarkable reduction occurred after cleaning, but significant microbial growth inhibition occurred only after disinfection. Nevertheless, viable microorganisms within the biofilm were still detected by confocal microscopy, more so with glutaraldehyde than with peracetic acid or O-phataladehyde. CONCLUSION: After the complete disinfection procedure, viable microorganisms could still be detected within the biofilm on endoscope channels. Prevention of biofilm development within endoscope channels should be a priority in disinfection procedures, particularly for ERCP and EUS.


Assuntos
Biofilmes/crescimento & desenvolvimento , Desinfecção/métodos , Endoscópios Gastrointestinais/microbiologia , Contaminação de Equipamentos/prevenção & controle , Trifosfato de Adenosina/análise , Brasil , Catéteres/microbiologia , Contagem de Colônia Microbiana , Desinfetantes , Glutaral , Medições Luminescentes , Microscopia Confocal , Mycobacterium/crescimento & desenvolvimento , Ácido Peracético , Pseudomonas aeruginosa/crescimento & desenvolvimento , Staphylococcus aureus/crescimento & desenvolvimento , o-Ftalaldeído
7.
Antimicrob Agents Chemother ; 58(10): 5766-74, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25049257

RESUMO

Mycobacterium leprae and Mycobacterium tuberculosis antimicrobial resistance has been followed with great concern during the last years, while the need for new drugs able to control leprosy and tuberculosis, mainly due to extensively drug-resistant tuberculosis (XDR-TB), is pressing. Our group recently showed that M. leprae is able to induce lipid body biogenesis and cholesterol accumulation in macrophages and Schwann cells, facilitating its viability and replication. Considering these previous results, we investigated the efficacies of two statins on the intracellular viability of mycobacteria within the macrophage, as well as the effect of atorvastatin on M. leprae infections in BALB/c mice. We observed that intracellular mycobacteria viability decreased markedly after incubation with both statins, but atorvastatin showed the best inhibitory effect when combined with rifampin. Using Shepard's model, we observed with atorvastatin an efficacy in controlling M. leprae and inflammatory infiltrate in the BALB/c footpad, in a serum cholesterol level-dependent way. We conclude that statins contribute to macrophage-bactericidal activity against Mycobacterium bovis, M. leprae, and M. tuberculosis. It is likely that the association of statins with the actual multidrug therapy effectively reduces mycobacterial viability and tissue lesion in leprosy and tuberculosis patients, although epidemiological studies are still needed for confirmation.


Assuntos
Antituberculosos/uso terapêutico , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Mycobacterium leprae/efeitos dos fármacos , Mycobacterium leprae/patogenicidade , Rifampina/uso terapêutico , Animais , Atorvastatina , Linhagem Celular , Sinergismo Farmacológico , Ácidos Heptanoicos/uso terapêutico , Humanos , Hanseníase/tratamento farmacológico , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/patogenicidade , Pirróis/uso terapêutico , Sinvastatina/uso terapêutico
8.
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
9.
Anaerobe ; 22: 121-2, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23644034

RESUMO

The aim of this study was to evaluate the sporicidal activity of hospital disinfectants against spores of two Brazilian Clostridium difficile ribotypes and the BI/NAP1/027. Our results showed that CloroRio(®) and Cidex Opa(®) were the most efficient agents for eliminating spores of C difficile.


Assuntos
Clostridioides difficile/efeitos dos fármacos , Desinfetantes/farmacologia , Glutaral/farmacologia , Esporos Bacterianos/efeitos dos fármacos , Brasil , Hospitais , Humanos
10.
J Antimicrob Chemother ; 67(10): 2396-400, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22729926

RESUMO

OBJECTIVES: An aqueous extract and fraction from the marine sponge Petromica citrina have antibacterial activity. We performed a chemical and biological characterization of the antibiotic substance from P. citrina and investigated its mode of action on Staphylococcus aureus cells. METHODS: The inhibitory activity of the aqueous extract of P. citrina was determined against 14 bacteria belonging to type strains and clinical antibiotic-resistant strains. The aqueous extract was fractionated under bioassay guidance and the bioactive substance was identified by its (1)H-NMR, (13)C-NMR and mass spectra. The MIC and the MBC of this substance were determined. This substance was also subjected to cytotoxic bioassays. The mode of action on S. aureus cells was investigated by light and transmission electron microscopy analysis. RESULTS: P. citrina showed a large spectrum of activity against type strains and resistant-bacteria such as S. aureus, Staphylococcus epidermidis, Enterococcus faecalis, Mycobacterium fortuitum and Neisseria gonorrhoeae. The aqueous extract was fractionated and halistanol trisulphate (24ε,25-dimethylcholestane-2ß,3α,6α-triol trisodium sulphate) was isolated for the first time from P. citrina. Halistanol trisulphate had a bactericidal effect on exponentially growing S. aureus cells at the MIC (512 mg/L). Cytotoxicity biossays showed moderate toxicity against cancer cell line L929 (fibrosarcoma). This substance apparently acts by damaging the cell membrane, with subsequent cell lysis. CONCLUSIONS: Halistanol trisulphate is a broad-spectrum antibiotic isolated from P. citrina with a mode of action involving disruption of the cytoplasmic membrane. It is a new candidate for research on antibacterial substances.


Assuntos
Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Poríferos/química , Esteróis/isolamento & purificação , Esteróis/farmacologia , Animais , Antibacterianos/química , Bactérias/citologia , Extratos Celulares/química , Extratos Celulares/isolamento & purificação , Extratos Celulares/farmacologia , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Fracionamento Químico , Espectroscopia de Ressonância Magnética , Camundongos , Testes de Sensibilidade Microbiana , Microscopia
11.
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
12.
Front Vet Sci ; 9: 1006090, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36467663

RESUMO

The species Mycobacterium tuberculosis variant bovis (M. tuberculosis var. bovis) is associated with tuberculosis, mainly in cattle and buffaloes. This pathogen has the potential to infect other mammals, including humans. Tuberculosis caused by M. tuberculosis var. bovis is a zoonosis clinically identical to tuberculosis caused by Mycobacterium tuberculosis, and the recommended treatment in humans results in the use of antibiotics. In this study, we used the whole genome sequencing (WGS) methodology Illumina NovaSeq 6000 System platform to characterize the genome of M. tuberculosis var. bovis in cattle circulating in Mato Grosso, identify mutations related to drug resistance genes, compare with other strains of M. tuberculosis var. bovis brazilian and assess potential drug resistance. Four isolates of M. tuberculosis var. bovis of cattle origin representing the main livestock circuits, which had been more prevalent in previous studies in the state of Mato Grosso, were selected for the genomic study. The genome sizes of the sequenced strains ranged from 4,306,423 to 4,332,964 bp, and the GC content was 65.6%. The four strains from Mato Grosso presented resistance genes to pncA (pyrazinamide), characterized as drug-resistant strains. In addition to verifying several point mutations in the pncA, rpsA, rpsL, gid, rpoB, katG, gyrB, gyrA, tlyA, embA, embB, embC, fgd, fbiB, and fbiC genes, these genes were similar to antibiotic resistance in more than 92% of the Brazilian strains. Therefore, our results indicated a high genetic diversity between our isolates and other M. tuberculosis var. bovis isolated in Brazil. Thus, multiple transmission routes of this pathogen may be present in the production chain. So, to achieve a bovine tuberculosis-free health status, the use of the WGS as a control and monitoring tool will be crucial to determine these transmission routes.

13.
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
15.
Rev Soc Bras Med Trop ; 53: e20200051, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32997049

RESUMO

INTRODUCTION: Laboratory and clinical features of childhood tuberculosis (TB) are non-specific and establishing an accurate diagnosis remains a challenge. This study evaluated a Single tube nested-PCR (STNPCR) to detect genomic DNA of Mycobacterium tuberculosis complex in blood and urine. METHODS: Biological samples were obtained from children (<15 years old) with clinical suspicion of pulmonary and extrapulmonary TB at public hospitals in Recife-Pernambuco, Brazil. Cultures yielded negative results in a majority of childhood TB cases, which are generally paucibacillary. A set of clinical, epidemiological, radiological, and laboratory criteria with evident clinical improvement after anti-TB treatment were frequently used to define childhood TB cases. RESULTS: Ninety children with clinical suspicion were enrolled in this study (44 with TB and 46 without TB). The pulmonary TB group had 20 confirmed cases and 46 negative controls, while the extrapulmonary TB group had 24 confirmed cases. The STNPCR showed sensitivities to pulmonary and extrapulmonary TB of 47.4% and 52.2% (blood) and 38.8% and 20% (urine), respectively. Considering the low performance of STNPCR on separate samples, we decided to perform a combined analysis (parallel sensitivity analysis) of the results from blood and urine samples. The parallel sensitivity increased to 65% in blood and 62.5% in urine. The specificity in both samples ranged from 93.5-97.8%. CONCLUSIONS: Although STNPCR showed moderate sensitivity, the specificity is high; therefore, the test can be used as an auxiliary tool to diagnose TB in children. It is a rapid test that demonstrated better performance than other diagnostic tests in paucibacillary samples as it does in childhood tuberculosis.


Assuntos
Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Pulmonar/diagnóstico , Adolescente , Brasil , Estudos de Casos e Controles , Criança , Pré-Escolar , Testes Diagnósticos de Rotina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Mycobacterium tuberculosis/genética , Reação em Cadeia da Polimerase , Estudos Prospectivos , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/urina
16.
Infect Genet Evol ; 85: 104550, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32920193

RESUMO

Human tuberculosis (TB) is caused by members of the Mycobacterium tuberculosis complex (MTBC), including Mycobacterium tuberculosis var. tuberculosis (MTB) and Mycobacterium tuberculosis var. africanum (MAF). While MTB is isolated worldwide, MAF is almost completely restricted to the African continent, and despite the historical proximity between Brazil and Africa during the slave trade, no case of TB being caused by MAF has been reported in Brazil to date. We hereby describe the first case of TB caused by MAF in Brazil comparing its genome against the published ones. A female patient who had never visited Africa presented with clinical symptoms typical of pulmonary TB. Based on 16S rRNA gene sequencing, the cultured isolate was identified as belonging to MTBC and partial sequence of the hsp65 gene was identical to that of MAF. This was confirmed by genotyping based on detection of Single Nucleotide Polymorphism (SNP), Region of Difference (RD) and spoligotyping. The isolate presented the Shared International Typing (SIT) 181. In the whole-genome comparison against MAF genomes available on published EMBL-EBI European Nucleotide Archive (ENA), the Brazilian genome (MAFBRA00707) was identified as belonging to Lineage 6 and clustered with isolates from The Gambia. This is the first report of the isolation of MAF from a patient from Brazil, without evidence of having any contact with an African index case.


Assuntos
Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Tuberculose Pulmonar/diagnóstico , Tuberculose Pulmonar/microbiologia , Brasil/epidemiologia , Genes Bacterianos , Genoma Bacteriano , Genótipo , Humanos , Epidemiologia Molecular , Tipagem Molecular , Mycobacterium tuberculosis/isolamento & purificação , Filogenia , Polimorfismo de Nucleotídeo Único , RNA Ribossômico 16S , Tuberculose Pulmonar/epidemiologia
17.
Infect Genet Evol ; 77: 104044, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31634644

RESUMO

Mycobacterium bovis is the main causative agent of bovine tuberculosis (bTB) being among the animal-adapted Mycobacterium tuberculosis complex. Herds can also be infected with non-tuberculous mycobacteria (NTM) causing a negative effect on the economy and on animal and human health through zoonotic infections. Molecular tools are required for mycobacteria identification; thus, it is laborious to determine the epidemiological information of mycobacteria among herds. We aimed to describe the mycobacterial pathogens associated with cases of suspected bTB lesions in cattle/buffaloes slaughtered for consumption and to investigate bTB transmission. We evaluated 74 lesion samples from 48 animals (27 bovine/21 buffaloes) from 16 mapped farms. Positives samples from nested-PCR were cultured in Lowenstein-Jensen (LJ), 2% pyruvate (LJ + P), and 2% glycerol (LJ + G) media, followed by Ziehl-Neelsen (ZN) staining technique and partial gene sequencing (hsp65, rpoB, and 16S-rRNA). Spoligotyping and 24-MIRU-VNTR were performed. The LJ + P increased the chance of obtaining bacilli. The respiratory tract and the oral cavity were the most important infection route. In addition, the calcified part of the lesions suggested chronic bTB. Spoligotypes of M. bovis (SIT986/SB0885) differed from others found in South America, and the MIRU-VNTR 24 loci suggested that bTB was associated to highly related strains. The NTM species found are of clinical importance in humans.


Assuntos
Tipagem Molecular/métodos , Infecções por Mycobacterium/veterinária , Mycobacterium/classificação , Zoonoses/microbiologia , Animais , Técnicas de Tipagem Bacteriana , Brasil , Búfalos , Bovinos , Evolução Molecular , Microbiologia de Alimentos , Humanos , Epidemiologia Molecular , Boca/microbiologia , Mycobacterium/genética , Mycobacterium/isolamento & purificação , Infecções por Mycobacterium/microbiologia , Filogenia , Sistema Respiratório/microbiologia
18.
J Clin Microbiol ; 47(7): 2149-55, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19403765

RESUMO

An epidemic of infections after video-assisted surgery (1,051 possible cases) caused by rapidly growing mycobacteria (RGM) and involving 63 hospitals in the state of Rio de Janeiro, Brazil, occurred between August 2006 and July 2007. One hundred ninety-seven cases were confirmed by positive acid-fast staining and/or culture techniques. Thirty-eight hospitals had cases confirmed by mycobacterial culture, with a total of 148 available isolates recovered from 146 patients. Most (n = 144; 97.2%) isolates presented a PRA-hsp65 restriction pattern suggestive of Mycobacterium bolletii or Mycobacterium massiliense. Seventy-four of these isolates were further identified by hsp65 or rpoB partial sequencing, confirming the species identification as M. massiliense. Epidemic isolates showed susceptibility to amikacin (MIC at which 90% of the tested isolates are inhibited [MIC(90)], 8 microg/ml) and clarithromycin (MIC(90), 0.25 microg/ml) but resistance to ciprofloxacin (MIC(90), >or=32 microg/ml), cefoxitin (MIC(90), 128 microg/ml), and doxycycline (MIC(90), >or=64 microg/ml). Representative epidemic M. massiliense isolates that were randomly selected, including at least one isolate from each hospital where confirmed cases were detected, belonged to a single clone, as indicated by the analysis of pulsed-field gel electrophoresis (PFGE) patterns. They also had the same PFGE pattern as that previously observed in two outbreaks that occurred in other Brazilian cities; we designated this clone BRA100. All five BRA100 M. massiliense isolates tested presented consistent tolerance to 2% glutaraldehyde. This is the largest epidemic of postsurgical infections caused by RGM reported in the literature to date in Brazil.


Assuntos
Infecção Hospitalar/epidemiologia , Surtos de Doenças , Infecções por Mycobacterium/epidemiologia , Mycobacterium/isolamento & purificação , Infecção da Ferida Cirúrgica/epidemiologia , Adulto , Proteínas de Bactérias/genética , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Chaperonina 60 , Chaperoninas/genética , Análise por Conglomerados , Infecção Hospitalar/microbiologia , Impressões Digitais de DNA , DNA Bacteriano/química , DNA Bacteriano/genética , RNA Polimerases Dirigidas por DNA/genética , Eletroforese em Gel de Campo Pulsado , Feminino , Genótipo , Humanos , Masculino , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Dados de Sequência Molecular , Mycobacterium/classificação , Infecções por Mycobacterium/microbiologia , Análise de Sequência de DNA , Infecção da Ferida Cirúrgica/microbiologia
19.
Colloids Surf B Biointerfaces ; 175: 306-313, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30553206

RESUMO

Tuberculosis is an infectious bacterial disease that causes millions of deaths worldwide. Current treatment recommended by WHO is effective, however it is an extensive and arduous process associated to severe adverse effects, which induces a low patient compliance and the emerging of multidrug resistant tuberculosis. Thus, as a main goal of this study, rifampicin nanoparticles were surface functionalized with a tuftsin-modifed peptide to selectively recognize receptors located on infected alveolar macrophages, enhancing nanoparticles uptake by these cells and improving antimycobacterial activity. A tuftsin-based modified peptide was synthesized and successfully attached to nanoparticles interface (NP-pRIF). In parallel, nanoparticles without peptide were also developed for comparison (NP-RIF). Physicochemical characterization demonstrated that stable and monodisperse nanodelivery systems were obtained, with a controlled drug release profile and non-cytotoxic potential. Moreover, nanoparticles containing peptide were significantly more internalized by macrophages than nanoparticles without peptide over a wide range of time. Both nanoparticles were 2-fold more effective against M. tuberculosis than free rifampicin, suggesting NP-pRIF as a promising strategy for the management of tuberculosis treatment.


Assuntos
Antituberculosos/farmacologia , Lipídeos/química , Macrófagos/efeitos dos fármacos , Mycobacterium tuberculosis/efeitos dos fármacos , Nanoestruturas/química , Rifampina/farmacologia , Animais , Antituberculosos/química , Antituberculosos/farmacocinética , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Macrófagos/citologia , Macrófagos/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Mycobacterium tuberculosis/fisiologia , Rifampina/química , Rifampina/farmacocinética , Tuftsina/química
20.
Infect Genet Evol ; 73: 337-341, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31170529

RESUMO

Lineage 1 (L1) is one of seven Mycobacterium tuberculosis complex (MTBC) lineages. The objective of this study was to improve the complex taxonomy of L1 using phylogenetic SNPs, and to look for the origin of the main L1 sublineage prevalent in Para, Brazil. We developed a high-throughput SNPs-typing assay based on 12-L1-specific SNPs. This assay allowed us to experimentally retrieve SNP patterns on nine of these twelve SNPs in 277 isolates previously tentatively assigned to L1 spoligotyping-based sublineages. Three collections were used: Pará-Brazil (71); RIVM, the Netherlands (102), Madagascar (104). One-hundred more results were generated in Silico using the PolyTB database. Based on the final SNPs combination, the samples were classified into 11 clusters (C1-C11). Most isolates within a SNP-based cluster shared a mutual spoligotyping-defined lineage. However, L1/EAI1-SOM (SIT48) and L1/EAI6-BGD1 (SIT591) showed a poor correlation with SNP data and are not monophyletic. L1/EAI8-MDG and L1/EAI3-IND belonged to C5; this result suggests that they share a common ancestor. L1.1.3/SIT129, a spoligotype pattern found in SNPs-cluster C6, was found to be shared between Pará/Brazil and Malawi. SIT129 was independently found to be highly prevalent in Mozambique, which suggests a migration history from East-Africa to Brazil during the 16th-18th slave trade period to Northern Brazil.


Assuntos
Variação Genética/genética , Mycobacterium tuberculosis/genética , População Negra/genética , Brasil , Genótipo , Humanos , Madagáscar , Moçambique , Países Baixos , Filogenia , Polimorfismo de Nucleotídeo Único/genética , Tuberculose/microbiologia
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