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1.
Microbiol Resour Announc ; 12(7): e0031223, 2023 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-37306576

RESUMO

Campylobacter spp. have been reported as one of the most frequent causes of acute gastroenteritis in humans worldwide. Here, we report 17 draft genome sequences of C. coli strains isolated from animal and food sources in Brazil. These data will improve our understanding of this species in Brazil.

2.
J Glob Antimicrob Resist ; 33: 109-113, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36944410

RESUMO

OBJECTIVES: This study aimed to identify antimicrobial resistance genotypes in 63 Campylobacter coli strains isolated from humans (12), animals (21), the environment (20), and food (10) in Brazil using whole genome sequencing (WGS) tools, comparing them with results obtained by antimicrobial susceptibility testing (AST) against some important antimicrobials in clinical use. METHODS: Phenotypic resistance profiles were determined by minimal inhibitory concentrations and the disk diffusion technique. The prediction of the resistance genes was performed using ABRicate v.0.8 and the Resistance Gene Identifier software of the CARD. RESULTS: The percentage of C. coli strains phenotypically resistant to antimicrobials were: ampicillin, 44.4%; doxycycline, 20.6%; tetracycline, 20.6%; ciprofloxacin, 12.7%; nalidixic acid, 12.7%; streptomycin, 6.3%; erythromycin, 4.8%; and gentamicin, 1.6%. The genes blaOXA-605 / blaOXA-61,tet(O), cmeB, aadE-Cc, aph (3 ') - IIIa, sat4 and aad9 were detected in 54%, 22.2%, 9.5%,6.3%, 1.6%, 1.6%, and 1.6% strains, respectively. Mutations T86I in the QRDR region of gyrA were detected in 8 (12.7%) strains. The agreement between AST and WGS was 100%, 92.9%, 82.4%, and 80% for quinolones, tetracycline, ß-lactam, and aminoglycoside classes, respectively. CONCLUSIONS: The rates of C. coli strains resistant to ß- lactams and quinolones may represent a public health concern. The partial agreement between AST and WGS shows that improvement in antibiotic resistance databases may be required to minimize this discrepancy observed in some antimicrobial classes and to become an acceptable tool to both clinical microbiologists and regulatory agencies.


Assuntos
Anti-Infecciosos , Infecções por Campylobacter , Campylobacter coli , Animais , Humanos , Antibacterianos/farmacologia , Brasil , Farmacorresistência Bacteriana/genética , Ciprofloxacina/farmacologia , Tetraciclina/farmacologia , Anti-Infecciosos/farmacologia , Fenótipo , Genótipo
3.
Genes (Basel) ; 12(10)2021 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-34680933

RESUMO

Campylobacter jejuni (C. jejuni) is responsible for 80% of human campylobacteriosis and is the leading cause of gastroenteritis globally. The relevant public health risks of C. jejuni are caused by particular virulence genes encompassing its virulome. We analyzed 40,371 publicly available genomes of C. jejuni deposited in the NCBI Pathogen Detection Database, combining their epidemiologic metadata with an in silico bioinformatics analysis to increase our current comprehension of their virulome from a global perspective. The collection presented a virulome composed of 126 identified virulence factors that were grouped in three clusters representing the accessory, the softcore, and the essential core genes according to their prevalence within the genomes. The multilocus sequence type distribution in the genomes was also investigated. An unexpected low prevalence of the full-length flagellin flaA and flaB locus of C. jejuni genomes was revealed, and an essential core virulence gene repertoire prevalent in more than 99.99% of genomes was identified. Altogether, this is a pioneer study regarding Campylobacter jejuni that has compiled a significant amount of data about the Multilocus Sequence Type and virulence factors concerning their global prevalence and distribution over this database.


Assuntos
Campylobacter jejuni/genética , Flagelina/genética , Campylobacter jejuni/patogenicidade , Frequência do Gene , Genoma Bacteriano , Virulência/genética
4.
Infect Genet Evol ; 95: 105018, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34332158

RESUMO

Campylobacter has been one of the most common causative agent of bacterial food-borne gastroenteritis in humans worldwide. However, in Brazil the campylobacteriosis has been a neglected disease and there is insufficient data to estimate the incidence of this pathogen in the country. AIMS: The current study aimed to determine the phylogenetic relationships among Campylobacter coli strains isolated in Brazil and to compare them with international Campylobacter isolates available in some public databases. METHODS AND RESULTS: A total of 63C. coli strains isolated in Brazil were studied. The MLST analysis showed 18 different STs including three STs not yet described in the PubMLST database. The cgMLST allocated the Brazilian strains studied into five main clusters and each cluster comprised groups of strains with nearly identical cgMLST profiles and with significant genetic distance observed among the distinct clusters. The comparison of the Brazilian strains with 3401 isolates from different countries showed a wide distribution of these strains isolated in this country. CONCLUSIONS: The results showed a high similarity among some strains studied and a wide distribution of the Brazilian strains when compared to isolates from different countries, which is an interesting data set since it showed a high genetic diversity of these strains from Brazil in a global context. This study contributed for a better genomic characterization of C. coli strains isolated in Brazil and provided important information about the diversity of this clinically-relevant pathogen.


Assuntos
Campylobacter coli/genética , Variação Genética , Genoma Bacteriano , Animais , Brasil , Galinhas/microbiologia , Água Doce/microbiologia , Humanos , Tipagem de Sequências Multilocus , Filogenia , Platirrinos/microbiologia , Esgotos/microbiologia
5.
Microb Drug Resist ; 27(5): 660-669, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33021437

RESUMO

Aims: The objectives of this work were to use whole genome sequencing (WGS) to determine the antimicrobial resistance genotypes of 116 Campylobacter jejuni strains isolated in Brazil and to compare it with the results obtained by antimicrobial susceptibility testing (AST). In addition, WGS was used to uncover the phylogenetic relationship among those strains. Results: By AST, the C. jejuni strains resistant to ciprofloxacin, tetracycline, doxycycline, and erythromycin were 51 (44%), 41 (35.3%), 41 (35.3%), and 6 (5.2%), respectively. By WGS, the genes aph(3')III, aadE, blaOXA-449, blaOXA-184, blaOXA-61, and tet(O) were detected in 6 (5.2%), 3 (2.6%), 1 (0.9%), 10 (8.6%), 55 (47.4%), and 44 (38%) strains, respectively. Fifty-four (46.6%) strains showed the mutation T86I in the gyrA gene, and four (3.4%) strains presented the mutation A2075G in the 23S rRNA gene. The correlation between AST and WGS was 100% for ciprofloxacin, 97.5% for tetracyclines, and 66.7% for erythromycin. The whole genome single nucleotide polymorphism (SNP) tree clustered the C. jejuni strains into two clades comprising strains that were highly related from different sources, places, and years. Conclusion: The high rates of C. jejuni strains resistant to ciprofloxacin and tetracyclines are of concern and may represent a public health problem. WGS has a potential to be a powerful tool for the prediction of resistance of antibiotics used to treat campylobacteriosis. The results obtained by whole genome SNP analysis suggested the potential for transmission between clinical and nonclinical sources and between human and animal sources over the course of 20 years in Brazil.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Campylobacter jejuni/efeitos dos fármacos , Campylobacter jejuni/genética , Genes Bacterianos/genética , beta-Lactamases/genética , Animais , Brasil/epidemiologia , Campylobacter jejuni/enzimologia , DNA Girase , Humanos , Testes de Sensibilidade Microbiana , Polimorfismo de Nucleotídeo Único , Sequenciamento Completo do Genoma
6.
Genome Announc ; 6(16)2018 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-29674540

RESUMO

Campylobacter jejuni is a major zoonotic pathogen that causes foodborne gastroenteritis worldwide. However, clinical cases of campylobacteriosis have been underreported and underdiagnosed in Brazil. Herein, we describe the draft genome sequences of 116 C. jejuni strains isolated from diverse sources in Brazil.

7.
J Med Microbiol ; 66(3): 350-359, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28317494

RESUMO

Purpose and methodology.Campylobacter jejuni is a major zoonotic pathogen that causes food-borne gastroenteritis worldwide. However, there are only a few studies available that have molecularly characterized C. jejuni strains isolated in Brazil. The aim of this study was to genotype 111 C. jejuni strains isolated from sick humans (43), monkey faeces (19), chicken faeces (14), chicken meat (33) and sewage (2) between 1996 and 2016 in Brazil using flaA-SVR (short variable region) sequencing and PFGE. Furthermore, the presence of 16 virulence genes was analysed by PCR. RESULTS: Using PFGE and flaA-SVR sequencing, the 111 C. jejuni strains studied were grouped into three and two clusters, respectively, and some strains of different origin presented a similarity of ≥80 %. In total, 35 flaA-SVR alleles were detected. Alleles gt45, gt49 and gt57 were the most prevalent, in contrast with those frequently described in the PubMLST database. All 111 C. jejuni strains contained the genes flaA, flhA, cadF, docA, cdtA, cdtB, cdtC, iamA, ciaB, sodB, dnaJ, pldA, racR and csrA. The wlaN gene was detected in 11 strains (9.9 %), and the virB11 in just one strain (0.9 %). CONCLUSIONS: In conclusion, the pathogenic potential of the C. jejuni strains studied was highlighted by the high frequency of the majority of the virulence genes searched. The flaA-SVR sequencing and PFGE results showed that some of the strains studied presented a high genotypic similarity, suggesting potential for transmission between animal sources and humans in this country. Altogether, the results characterize further C. jejuni isolates from Brazil, an important producer and exporter of chicken meat.


Assuntos
Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Campylobacter jejuni/patogenicidade , Doenças Transmitidas por Alimentos/microbiologia , Variação Genética , Fatores de Virulência/genética , Animais , Brasil/epidemiologia , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/transmissão , Galinhas/microbiologia , Fezes/microbiologia , Flagelina/genética , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Gastroenterite/epidemiologia , Gastroenterite/microbiologia , Genes Bacterianos , Genótipo , Haplorrinos/microbiologia , Humanos , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/microbiologia , Reação em Cadeia da Polimerase , Aves Domésticas/microbiologia , Prevalência , Análise de Sequência de DNA , Esgotos/microbiologia , Virulência
8.
Vigil. sanit. debate ; 3(1): [8], fev. 2015.
Artigo em Português | LILACS | ID: biblio-916416

RESUMO

O consumo da carne de frango é comum no Brasil por ser um alimento proteico de alto valor biológico e baixo custo, sendo acessível a toda população. Uma causa comum de infecções alimentares tem sido a ingestão de produtos avícolas contaminados, crus ou insuficientemente cozidos, fazendo da contaminação de cortes de frango fontes potenciais de Campylobacter spp. para o homem. O objetivo deste estudo foi detectar a presença de Campylobacter e verificar a possível veiculação da campilobacteriose através de cortes e miúdos de frangos resfriados e comercializados para consumo em supermercados de grande porte no estado do Rio de Janeiro. Para isso, foram coletadas 40 amostras resfriadas de frango, das quais 19 foram embaladas pela indústria e 21 manipuladas pelos supermercados, submetendo-as a três metodologias distintas denominadas: in natura, enriquecimento e incubação da água de lavagem. Os resultados obtidos revelaram a presença de espécies de Campylobacter zoonóticas resistentes a antimicrobianos em cortes de frango comercializados para consumo humano, indicando que pedaços e miúdos de frango crus ou insuficientemente cozidos são fontes potenciais de campilobacteriose para a população.


The consumption of chicken meat is common in Brazil because this protein-rich food is low cost, has high nutritional value, and is accessible to the entire population. A common cause of foodborne illness has been the ingestion of contaminated, raw, or undercooked poultry products, making contaminated chicken meat a potential source of Campylobacter spp. to humans. The objective of this study was to detect the presence of Campylobacter and assess the potential transmission of campylobacteriosis through refrigerated chicken meat and organ sold for consumption in large supermarkets in the state of Rio de Janeiro. For this purpose, 40 samples of refrigerated chicken were collected; 19 of these were industrially packed and 21 were manipulated in the supermarkets. The samples were subjected to analysis using three different methodologies: in natura, by enrichment, and by incubation of the rinse water. The results revealed the presence of zoonotic, antimicrobial-resistant Campylobacter species in chicken meat marketed for human consumption, indicating that raw or undercooked chicken pieces and organs are potential sources of human campylobacteriosis.


Assuntos
Humanos , Campylobacter , Contaminação de Alimentos , Análise de Perigos e Pontos Críticos de Controle , Brasil , Vigilância Sanitária de Produtos , Manipulação de Alimentos
9.
Rio de Janeiro; s.n; 2012. 114 p. ilus, mapas, tab, graf.
Tese em Português | LILACS | ID: lil-638261

RESUMO

O mercúrio (Hg) é considerado um dos poluentes ambientais mais perigosos,devido a sua persistência no ambiente, eficiente transporte atmosférico e elevadatoxicidade. A biogeoquímica do Hg em ambientes aquáticos é controladaprincipalmente por reações mediadas por bactérias. Dentre elas, a mais relevante doponto de vista da redução do risco do Hg é a redução dos íons mercúricos à formaelementar, menos tóxica, devido à presença do gene merA, que codifica a enzima mercúrio-redutase. Neste estudo, 123 bactérias Gram-negativas resistentes ao Hg foram isoladas de ecossistemas aquáticos brasileiros (RJ, RO, MT e RS). Foram isoladas bactérias resistentes ao Hg em todos os pontos de coleta. A maioria dos isolados foi identificada como E. cloacae, K. pneumoniae, Pantoea sp., E. coli e Serratia sp., indicando contaminação fecal das áreas estudadas. Independente do histórico decontaminação mercurial local, a maioria das amostras apresentou Concentração Mínima Inibitória de Hg igual a 20 micrometro e foi resistente a pelo menos um dos antimicrobianos testados. O gene merA foi detectado em 91 por cento dos isolados, utilizando PCR. A caracterização do gene merA através de sequenciamento confirmou a especificidade dos produtos de amplificação que apresentaram grande similaridade entre si e uma altadivergência genética em relação às sequências identificadas em outros países. Isto sugere a ocorrência de eventos genéticos ao longo do tempo, que resultaram no polimorfismo genético observado no gene merA. A partir dos dados obtidos neste estudo, esperamos contribuir para o avanço do conhecimento sobre a resistência ao Hg,relacionada ao gene merA e suas possíveis aplicações para a biorremediação da poluiçãoambiental.


Assuntos
Humanos , Ambiente Aquático/prevenção & controle , Bactérias Gram-Negativas/isolamento & purificação , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana , Riscos Ambientais , Mercúrio/toxicidade , Intoxicação por Mercúrio/genética , Poluição Ambiental/prevenção & controle
10.
Cad. saúde colet., (Rio J.) ; 16(4): 677-700, out.-dez. 2008. graf
Artigo em Português | LILACS-Express | LILACS | ID: lil-621226

RESUMO

Este artigo apresenta uma síntese crítica da literatura sobre a tecnologia dos biossensores. Os princípios nos quais se baseia esta nova abordagem analítica, suas principais características que a diferenciam dos outros métodos tradicionais (químicos e bioensaios), as múltiplas configurações e tipos que têm sido desenvolvidos por pesquisadores das mais variadas áreas da ciência e uma definição adequada para esta nova classe de sistemas analíticos são examinados. Por fim, as diversas aplicações dos biossensores, com ênfase para o monitoramento de poluentes ambientais perigosos para a saúdehumana (ex: pesticidas, metais, fenol, nitrito, disruptores endócrinos, etc.) e as perspectivas futuras nesta área são discutidas.


This article presents a critical review of the literature about the biosensor technology. The principles of this new analytical approach, its main unique characteristics and the multiple configurations or types developed, as well as a suitable definition for this class of analytical systems are evaluated. The various applications of the biosensors in several areas, specially for the monitoring of environmental pollutants (e.g. pesticides, metals, phenol, nitrite, endocrine disruptors, etc.) hazardous to human health, and the future perspectives in this filed are discussed.

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