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1.
Lancet ; 394(10202): 953-966, 2019 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-31526739

RESUMO

Drug-resistant tuberculosis is a major public health concern in many countries. Over the past decade, the number of patients infected with Mycobacterium tuberculosis resistant to the most effective drugs against tuberculosis (ie, rifampicin and isoniazid), which is called multidrug-resistant tuberculosis, has continued to increase. Globally, 4·6% of patients with tuberculosis have multidrug-resistant tuberculosis, but in some areas, like Kazakhstan, Kyrgyzstan, Moldova, and Ukraine, this proportion exceeds 25%. Treatment for patients with multidrug-resistant tuberculosis is prolonged (ie, 9-24 months) and patients with multidrug-resistant tuberculosis have less favourable outcomes than those treated for drug-susceptible tuberculosis. Individualised multidrug-resistant tuberculosis treatment with novel (eg, bedaquiline) and repurposed (eg, linezolid, clofazimine, or meropenem) drugs and guided by genotypic and phenotypic drug susceptibility testing can improve treatment outcomes. Some clinical trials are evaluating 6-month regimens to simplify management and improve outcomes of patients with multidrug-resistant tuberculosis. Here we review optimal diagnostic and treatment strategies for patients with drug-resistant tuberculosis and their contacts.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Antituberculosos/administração & dosagem , Esquema de Medicação , Farmacorresistência Bacteriana Múltipla/genética , Saúde Global , Humanos , Testes de Sensibilidade Microbiana/métodos , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
2.
Mem Inst Oswaldo Cruz ; 114: e190105, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31389522

RESUMO

BACKGROUND: Healthcare-associated infections caused by bacteria such as Pseudomonas aeruginosa are a major public health problem worldwide. Gene regulatory networks (GRN) computationally represent interactions among regulatory genes and their targets. They are an important approach to help understand bacterial behaviour and to provide novel ways of overcoming scientific challenges, including the identification of potential therapeutic targets and the development of new drugs. OBJECTIVES: The goal of this study was to reconstruct the multidrug-resistant (MDR) P. aeruginosa GRN and to analyse its topological properties. METHODS: The methodology used in this study was based on gene orthology inference using the reciprocal best hit method. We used the genome of P. aeruginosa CCBH4851 as the basis of the reconstruction process. This MDR strain is representative of the sequence type 277, which was involved in an endemic outbreak in Brazil. FINDINGS: We obtained a network with a larger number of regulatory genes, target genes and interactions as compared to the previously reported network. Topological analysis results are in accordance with the complex network representation of biological processes. MAIN CONCLUSIONS: The properties of the network were consistent with the biological features of P. aeruginosa. To the best of our knowledge, the P. aeruginosa GRN presented here is the most complete version available to date.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Redes Reguladoras de Genes , Pseudomonas aeruginosa/genética , Genoma Bacteriano , Família Multigênica , Infecções por Pseudomonas/genética , Valores de Referência
3.
Mem Inst Oswaldo Cruz ; 114: e190079, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31411309

RESUMO

A total of 124 Neisseria gonorrhoeae isolates recovered during a 12-year period (2003-2015) from outpatients assisted at Centro de Referência e Treinamento DST/AIDS-CRT of São Paulo city, Brazil, were analysed. The following resistance rates were observed: penicillin-59.6%, ciprofloxacin-15.3%, and azithromycin-6.7%. Although reduced susceptibility to these drugs was observed since 2003, no ceftriaxone-resistant isolates were detected. Ciprofloxacin- and azithromycin non-susceptible isolates were grouped in 11 clusters. Mutations were detected in GyrA and ParC of isolates 124 and 260, and a C2611T substitution on 23S rRNA alleles was also observed in isolate 260. Both isolates belonged to ST1901/ST6210 (MSLT/NG-MAST schemes).


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Neisseria gonorrhoeae/efeitos dos fármacos , Neisseria gonorrhoeae/genética , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Mutação , Fatores de Tempo , População Urbana
4.
BMC Infect Dis ; 19(1): 620, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31299909

RESUMO

BACKGROUND: Escherichia coli lineage ST131 predominates across various spectra of extra-intestinal infections, including urinary tract infection (UTI). The distinctive resistance profile, diverse armamentarium of virulence factors and rapid global dissemination of ST131 E. coli makes it an intriguing pathogen. However, not much is known about the prevalence and genetic attributes of ST131 lineage in Pakistan. METHODS: We estimated prevalence and genetic attributes of E. coli ST131 isolates causing UTI among 155 randomly selected samples. Samples were analyzed for phylogenetic grouping, O-typing and fumC/fimH typing. Isolates were further tested for the ESBL and virulence factors using PCR. RESULTS: Overall, 59% of the UPEC isolates belonged to the phylogenetic group B2, followed by D = 28%, B1 = 8% and A = 5%. Among 18 different Sequence-types, ST131 was the dominant lineage (n = 71; 46%) out of which 72% of the isolates were assigned to the phylogenetic group B2, while 61% adhered to the serogroup O25b. FumC/fimH typing confirmed 49% of the ST131 as H30 sub-types. In this study, significant numbers of the identified ST131 isolates were MDR and 42% showed ESBL phenotypes, out of which 37% carried bla-CTX-M-15. Moreover, different virulence factors were detected in following percentages: fimH,155(100%), iutA 86 (55%), feoB 76 (49%), papC 75 (48%), papGII 70 (45%), kpsMTII 40 (26%), papEF 37 (24%), fyuA 37 (24%), usp 22 (14%), papA 20 (13%), sfa/foc20 (13%), hlyA 18 (12%), afa 15 (10%), cdtB 11 (7%), papGI 6 (4%), papGIII 6 (4%), kpsMTIII 4 (3%) and bmaE2 (1%). CONCLUSION: Conclusively, this study provides important insight into the genetic and virulence attributes of pandemic MDR ST131 strains involved in UTIs. It also highlights higher prevalence of ST131-O25b-H30 UPEC isolates in patients, which was previously unreported from this part of globe.


Assuntos
Infecções por Escherichia coli/microbiologia , Infecções Urinárias/diagnóstico , Escherichia coli Uropatogênica/classificação , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/epidemiologia , Feminino , Humanos , Masculino , Paquistão/epidemiologia , Filogenia , Prevalência , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Escherichia coli Uropatogênica/isolamento & purificação , Escherichia coli Uropatogênica/patogenicidade , Virulência , Fatores de Virulência/classificação , Fatores de Virulência/genética , beta-Lactamases/classificação , beta-Lactamases/genética
5.
World J Microbiol Biotechnol ; 35(8): 115, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31332542

RESUMO

Antibiotic and arsenic (As) contaminations are worldwide public health problems. Previously, the bacterial ABC-type efflux protein MacAB reportedly conferred resistance to macrolide-type antibiotics but not to other metal(loid)s. In this study, the roles of MacAB for the co-resistance of different antibiotics and several metal(loid)s were analyzed in Agrobacterium tumefaciens 5A, a strain resistant to arsenite [As(III)] and several types of antibiotics. The macA and macB genes were cotranscribed, and macB was deleted in A. tumefaciens 5A and heterologously expressed in Escherichia coli AW3110 and E. coli S17-1. Compared to the wild-type strain 5A, the macB deletion strain reduced bacterial resistance levels to several macrolide-type and penicillin-type antibiotics but not to cephalosporin-type antibiotics. In addition, the macB deletion strain showed lower resistance to As(III) but not to arsenate [As(V)], antimonite [Sb(III)] and cadmium chloride [Cd(II)]. The mutant strain 5A-ΔmacB cells accumulated more As(III) than the cells of the wild-type. Furthermore, heterologous expression of MacAB in E. coli S17-1 showed that MacAB was essential for resistance to macrolide, several penicillin-type antibiotics and As(III) but not to As(V). Heterologous expression of MacAB in E. coli AW3110 reduced the cellular accumulation of As(III) but not of As(V), indicating that MacAB is responsible for the efflux of As(III). These results demonstrated that, in addition to macrolide-type antibiotics, MacAB also conferred resistance to penicillin-type antibiotics and As(III) by extruding them out of cells. This finding contributes to a better understanding of the bacterial resistance mechanisms of antibiotics and metal(loid)s.


Assuntos
Agrobacterium tumefaciens/genética , Proteínas de Bactérias/genética , DNA Bacteriano/isolamento & purificação , Farmacorresistência Bacteriana Múltipla/genética , Macrolídeos/farmacologia , Agrobacterium tumefaciens/metabolismo , Arsenitos/farmacologia , Proteínas de Bactérias/metabolismo , Cefalosporinas/farmacologia , DNA Bacteriano/genética , Eritromicina/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Deleção de Genes , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos , Penicilinas/farmacologia
6.
Vet Microbiol ; 235: 110-117, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282368

RESUMO

Bovine Respiratory Disease (BRD) is a major threat to animal health and welfare in the cattle industry. Strains of Mannheimia haemolytica (Mh) that are resistant to multiple classes of antimicrobials are becoming a major concern in the beef industry, as the frequency of isolation of these strains has been increasing. Mobile genetic elements, such as integrative conjugative elements (ICE), are frequently implicated in this rapid increase in multi-drug resistance. The objectives of the current study were to determine the genetic relationship between the isolates collected at arrival before metaphylaxis and at revaccination after metaphylaxis, to identify which resistance genes might be present in these isolates, and to determine if they were carried on an ICE. Twenty calves culture positive for Mh at arrival and revaccination were identified, and a total of 48 isolates with unique susceptibility profiles (26 from arrival, and 22 from revaccination) were submitted for whole-genome sequencing (WGS). A phylogenetic tree was constructed, showing the arrival isolates falling into four clades, and all revaccination isolates within one clade. All revaccination isolates, and one arrival isolate, were positive for the presence of an ICE. Three different ICEs with resistance gene modules were identified. The resistance genes aphA1, strA, strB, sul2, floR, erm42, tetH/R, aadB, aadA25, blaOXA-2, msrE, mphE were all located within an ICE. The gene bla-ROB1 was also present in the isolates, but was not located within an ICE.


Assuntos
Antibacterianos/farmacologia , Bovinos/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Mannheimia haemolytica/efeitos dos fármacos , Mannheimia haemolytica/genética , Pasteurelose Pneumônica/microbiologia , Animais , Antibacterianos/uso terapêutico , Dissacarídeos/uso terapêutico , Variação Genética , Genoma Bacteriano , Compostos Heterocíclicos/uso terapêutico , Imunização Secundária , Sequências Repetitivas Dispersas , Mannheimia haemolytica/isolamento & purificação , Testes de Sensibilidade Microbiana , Pasteurelose Pneumônica/tratamento farmacológico , Filogenia , Vacinação , Sequenciamento Completo do Genoma
7.
BMC Infect Dis ; 19(1): 629, 2019 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-31315572

RESUMO

BACKGROUND: Nosocomial infections and persistence of multidrug resistant biofilm forming Acinetobacter baumannii in hospitals has made it as a serious problem in healthcare settings worldwide. METHODS: A total of 100 A. baumannii clinical isolates from immunocompromised patients hospitalized in ICU were investigated for biofilm formation, the presence of biofilm related genes (bap, ompA, csuE, fimH, epsA, blaPER-1, bfmS, ptk, pgaB, csgA, kpsMII), integron characterization and molecular typing based on REP-PCR. RESULTS: All isolates were resistant to three or more categories of antibiotics and considered as multidrug resistant (MDR). A total of 32 isolates were resistant to all tested antibiotics and 91% were extensively drug-resistance (XDR). All isolates were able to produce biofilm and 58% of isolates showed strong ability to biofilm formation. All strong biofilm forming A. baumannii isolates were XDR. All A. baumannii isolates carried at least one biofilm related gene. The most prevalent gene was csuE (100%), followed by pgaB (98%), epsA and ptk (95%), bfmS (92%) and ompA (81%). 98% of isolates carried more than 4 biofilm related genes, simultaneously. Class I integron (67%) was more frequent in comparison with class II (10%) (P < 0.05). The REP-PCR patterns were classified as 8 types (A-H) and 21 subtypes. The A1 (23%) and C1 (15%) clusters were the most prevalent among A. baumannii isolates (P < 0.05). According to the REP-PCR patterns, 23% of all isolates had a clonal relatedness. CONCLUSION: Our study revealed the high frequency of biofilm forming XDR A. baumannii in ICU patients, with a high prevalence of biofilm related genes of csuE and pgaB. It seems that the appropriate surveillance and control measures are essential to prevent the emergence and transmission of XDR A. baumannii in our country.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/patogenicidade , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Biofilmes/efeitos dos fármacos , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Humanos , Hospedeiro Imunocomprometido , Unidades de Terapia Intensiva , Irã (Geográfico) , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Virulência
8.
BMC Infect Dis ; 19(1): 609, 2019 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-31296179

RESUMO

BACKGROUND: Bloodstream infections (BSI) are associated with high morbidity and mortality. This scenario worsens with the emergence of drug-resistant pathogens, resulting in infections which are difficult to treat or even untreatable with conventional antimicrobials. The aim of this study is to describe the epidemiological aspects of BSI caused by multiresistant gram-negative bacilli (MDR-GNB). METHODS: We conducted a laboratory-based surveillance for gram-negative bacteremia over a 1-year period. The bacterial isolates were identified by MALDI-TOF/MS and the antimicrobial susceptibility testing was performed by VITEK®2. Resistance genes were identified through PCR assays. RESULTS: Of the 143 patients, 28.7% had infections caused by MDR-GNB. The risk factors for MDR bacteremia were male sex, age ≥ 60, previous antimicrobial use, liver disease and bacteremia caused by K. pneumoniae. K. pneumoniae was the most frequently observed causative agent and had the highest resistance level. Regarding the resistance determinants, SHV, TEM, OXA-1-like and CTX-M-gp1 were predominant enzymatic variants, whereas CTX-M-gp9, CTX-M-gp2, KPC, VIM, GES, OXA-48-like, NDM and OXA-23-like were considered emerging enzymes. CONCLUSIONS: Here we demonstrate that clinically relevant antibiotic resistance genes are prevalent in this setting. We hope our findings support the development of intervention measures by policy makers and healthcare professionals to face antibiotic resistance.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Adolescente , Adulto , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Brasil/epidemiologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/microbiologia , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência
9.
J Med Microbiol ; 68(7): 986-990, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31162025

RESUMO

A colistin-resistant Salmonella enterica 4, [5],12:i:- sequence type (ST) 34 harbouring mcr-3.1 was recovered from a patient who travelled to China 2 weeks prior to diarrhoea onset. Genomic analysis revealed the presence of the mcr-3.1 gene located in the globally disseminated IncHI2 plasmid, highlighting the intercontinental dissemination of the colistin-resistant S. enterica 4, [5],12:i:- ST34 pandemic clone.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana Múltipla/genética , Plasmídeos/genética , Salmonella enterica/efeitos dos fármacos , Transferases (Outros Grupos de Fosfato Substituídos)/metabolismo , Proteínas de Bactérias/genética , China , Humanos , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação , Transferases (Outros Grupos de Fosfato Substituídos)/genética , Viagem
10.
Int J Food Microbiol ; 304: 119-126, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31195259

RESUMO

Staphylococcus aureus encodes numerous toxins that are known or strongly suspected to cause specific diseases or symptoms. Panton-Valentine leukocidin (PVL) is one of these important toxins that is associated with high mortality rates. In our previous study, 1581 S. aureus strains were isolated from 4300 samples of retail foods obtained from most of the provincial capitals in China from 2011 to 2016. This study aimed to investigate the prevalence of PVL-positive S. aureus isolates from retail foods in China and characterize these isolates by antibiotic resistance testing, spa typing, multilocus sequence typing (MLST) and enterotoxin gene analyses. In total, seventy-two isolates (72/1581, 4.6%) possessed pvl genes, including 24.1% MRSA isolates (26/108) and 3.1% MSSA isolates (46/1473), covering different types of food. The strains were divided into seventeen sequence types (STs) and twenty-seven spa types, and 43.1% (31/72) of the PVL-positive S. aureus isolates belonged to CC59-t437. These isolates contained at least one of the following enterotoxin genes: sei (97.2%), sem (86.1%), seq (80.6%), seg (68.1%), sek (68.1%), seb (62.5%), sel (52.8%), sej (50.0%), seh (48.6%), sep (45.8%), sea (38.9%), ser (37.5%), sen (27.8%), sec (16.7%), see (16.7%), sed (6.9%), seo (6.9%) and seu (6.7%). A total of 87.5% of the S. aureus isolates (63/72) harboured the classic SE genes (sea, seb, sec, sed, and see), whereas all the S. aureus isolates harboured the genes of the egc cluster (seg, sei, sem, sen, seo, and seu). In antimicrobial susceptibility tests, 98.6% of the isolates (71/72) exhibited resistance to at least one antibiotic, including 47 multi-drug-resistant isolates. Resistance to penicillin (94.4%), erythromycin (83.4%), clindamycin (63.9%), kanamycin (61.1%), telithromycin (58.3%), streptomycin (51.4%), tetracycline (47.2%), chloramphenicol (27.8%), fusidic acid (27.8%) and other antibiotics (<20%) was observed. All the PVL-positive MRSA isolates belonged to CC59-t437, which is the predominant type of community-associated (CA)-MRSA in China. The presence of these isolates in food represents a potential health risk for consumers and warrants further attention.


Assuntos
Toxinas Bacterianas/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterotoxinas/genética , Exotoxinas/genética , Leucocidinas/genética , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Infecções Estafilocócicas/epidemiologia , Antibacterianos/farmacologia , China/epidemiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos/métodos , Doenças Transmitidas por Alimentos/microbiologia , Genótipo , Humanos , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Tipagem de Sequências Multilocus , Prevalência , Infecções Estafilocócicas/microbiologia
11.
BMC Infect Dis ; 19(1): 556, 2019 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-31238885

RESUMO

BACKGROUND: In recent decades, Mycobacterium tuberculosis with the RDRio genotype, frequently isolated from tuberculosis patients in Rio de Janeiro, has become part of the Latin American - Mediterranean (LAM) family and has been associated with multidrug-resistant tuberculosis (MDR-TB). The aim of this study was to investigate the frequency of M. tuberculosis RDRio in the state of Minas Gerais, Brazil, and its relationship with MDR-TB. METHODS: For convenience, 172 susceptible and 63 MDR M. tuberculosis isolates were taken from pulmonary samples from patients diagnosed between January 2007 and December 2011. The DNA extracted from these isolates was analyzed by spoligotyping, PCR-RFLP to characterize fbpC103/Ag85C103, multiplex PCR to detect RDRio and RD174, and MIRU-VNTR 24 loci. RESULTS: Among the 235 isolates, the RDRio pattern was identified in 122 (51.9%) isolates (IC 0.45-0.58), with 100 (42.5%) wild-type and 13 (5.5%) mixed pattern isolates, whereas RD174 was identified in 93 of the 122 RDRio positive samples (76.3%). The LAM family and the LAM9 lineage were the most frequently identified among the isolates in this study. Among the 63 MDR isolates, 41 (65.1%) were RDRio and 28 (44.4%) RD174. CONCLUSION: The association of both deletions with MDR proved to be statistically significant, corroborating the few reports that have associated RDRio with MDR.


Assuntos
Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Técnicas de Tipagem Bacteriana , Brasil/epidemiologia , Farmacorresistência Bacteriana Múltipla/genética , Frequência do Gene , Estudos de Associação Genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Repetições Minissatélites , Reação em Cadeia da Polimerase/métodos , Polimorfismo de Fragmento de Restrição , Polimorfismo de Nucleotídeo Único , Tuberculose/epidemiologia , Tuberculose/microbiologia
12.
Ecotoxicol Environ Saf ; 181: 472-480, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31228823

RESUMO

Heavy metal pollution is one of the most widespread and complex environmental issues globally, posing a great threat to the ecosystem as well as human health. Bioremediation through heavy metal-resistant bacteria (HMRB) is currently the most promising technology to address this issue. To obtain HMRB to remediate heavy metal pollution potentially, 15 culturable HMRB strains were isolated from the sludge samples of an electroplating wastewater treatment plant (EWWTP), which belonged to the Bacillus, Shewanella, Lysinibacillus, and Acinetobacter genera. Their maximum tolerance concentrations to Cu2+, Ni2+, Mn2+, Co2+, and Cr2O72- were 40 mM, 10 mM, 200 mM, 40 mM, and 10 mM, respectively, and strain Mn1-4 showed much higher Mn2+ tolerance and removal effectiveness (3.355 g/L) than previously published reports. Moreover, multiple heavy metal-resistant genotypes and phenotypes were identified among these strains, of which strain Co1-1 carried the most of resistant gene sequences (10) and exhibited resistance to 7 categories of heavy metals, and the co-occurrence of heavy metal and antibiotic resistance were clearly observed in strain Ni1-3. In addition, flanked insert sequence (IS) elements on the heavy metal resistant genes (HMRGs) suggested that horizontal gene transfer (HGT) events may have resulted in multiple heavy metal resistance phenotypes and genotypes in these strains, and IS982 family transposase was presumed to result in the high Ni2+ tolerance in strain Ni1-3. This study expands our understanding of bacterial heavy metal resistance and provides promising candidates for heavy metal bioremediation.


Assuntos
Bactérias/metabolismo , Galvanoplastia , Metais Pesados/metabolismo , Águas Residuárias/microbiologia , Poluentes Químicos da Água/metabolismo , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/isolamento & purificação , Biodegradação Ambiental , Farmacorresistência Bacteriana Múltipla/genética , Transferência Genética Horizontal , Humanos , Metais Pesados/farmacologia , Esgotos/química , Esgotos/microbiologia , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/farmacologia
13.
Future Microbiol ; 14: 691-704, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31148474

RESUMO

Aim: To determine the prevalence of New Delhi metallo-ß-lactamase (NDM)-producing Gram-negative pathogens isolated from children's samples. Materials & methods: Carbapenem-resistant clinical isolates (n = 117) were confirmed by VITEK® 2 compact system, matrix-assisted laser desorption ionization-time of flight and multilocus sequence typing. MIC (µg/ml) of various antibiotics was determined by VITEK 2 compact system. Molecular characterization of the isolates was performed by PCR, DNA sequencing, PFGE and DNA hybridization. Results: Out of 117 carbapenemase producers, 37 (31.6%) and 29 (24.7%) were Klebsiella pneumoniae and Acinetobacter baumannii, respectively. 72 (61.5%) isolates were NDM positive and among these 60, 9 and 3 were NDM-1, -5 and -7, respectively. Majority of the NDM-producing K. pneumoniae belonged to ST11 and ST273 while most of the Escherichia coli belonged to ST405 and ST101. blaNDM were mainly located on 150kb plasmids. MIC displayed high resistance against ß-lactams drugs including carbapenems, and the most sensitive drugs were tigecycline and colistin. Conclusion: Dissemination of blaNDM-producing pathogens, particularly in children clinical settings, is a matter of great public health concern.


Assuntos
Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/genética , beta-Lactamases/biossíntese , beta-Lactamases/genética , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Proteínas de Bactérias/biossíntese , Proteínas de Bactérias/genética , Criança , DNA Bacteriano/análise , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Perfilação da Expressão Gênica , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/epidemiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Paquistão/epidemiologia , Plasmídeos , Análise de Sequência de DNA
14.
BMC Infect Dis ; 19(1): 553, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234780

RESUMO

BACKGROUND: Kazakhstan remains a high-burden TB prevalence country with a concomitent high-burden of multi-drug resistant tuberculosis. For this reason, we performed an in depth genetic diversity and population structure characterization of Mycobacterium tuberculosis complex (MTC) genetic diversity in Kazakhstan with both patient and community benefit. METHODS: A convenience sample of 700 MTC DNA cultures extracts from 630 tuberculosis patients recruited from 12 out of 14 regions in Kazakhstan, between 2010 and 2015, was independently studied by high-throughput hybridization-based methods, TB-SPRINT (59-Plex, n = 700), TB-SNPID (50-Plex, n = 543). DNA from 391 clinical isolates was successfully typed by two methods. To resolve the population structure of drug-resistant clades in more detail two complementary assays were run on the L2 isolates: an IS6110-NTF insertion site typing assay and a SigE SNP polymorphism assay. RESULTS: Strains belonged to L2/Beijing and L4/Euro-American sublineages; L2/Beijing prevalence totaled almost 80%. 50% of all samples were resistant to RIF and to INH., Subtyping showed that: (1) all L2/Beijing were "modern" Beijing and (2) most of these belonged to the previously described 94-32 sublineage (Central Asian/Russian), (3) at least two populations of the Central Asian/Russian sublineages are circulating in Kazakhstan, with different evolutionary dynamics. CONCLUSIONS: For the first time, the global genetic diversity and population structure of M. tuberculosis genotypes circulating in Kazakhstan was obtained and compared to previous local studies. Results suggest a region-specific spread of a very limited number of L2/Beijing clonal complexes in Kazakhstan many strongly associated with an MDR phenotype.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Adulto , Idoso , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , DNA Bacteriano/isolamento & purificação , DNA Bacteriano/metabolismo , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Evolução Molecular , Variação Genética , Genótipo , Humanos , Cazaquistão/epidemiologia , Masculino , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Hibridização de Ácido Nucleico/métodos , Fenótipo , Prevalência , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto Jovem
15.
J Physiol Pharmacol ; 70(1)2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31172969

RESUMO

The incidence of tuberculosis (TB) in some countries increases continuously, especially caused by mycobacterial strains resistant to various anti-tuberculotic drugs (AT). The emergence and spread of drug-resistant tuberculosis (multidrug-resistant - MDR-TB, and extensively drug-resistant - XDR-TB) suggest the crucial role of pharmacotherapy protocol tailored to the respective patient with MDR-TB or XDR-TB (a personalized approach) and requirements for fast and precise diagnostics of the degree of resistance. The aim of this study was to characterize a molecular basis of resistance to AT, and to identify the presence of the resistance using conventional susceptibility testing and molecular genetic methods using PCR tests in Slovakia during years 2009 - 2017. Furthermore, we focused on evaluation of the relationship between the level of resistance, the clinical status, and some laboratory markers of patients with drug-resistant TB. Totally 1157 strains isolated from patients in 2009 - 2017 were tested for resistance using classical methods and in resistant strains, the molecular-genetic tests were performed. Increased incidence of recurrence, prolonged time required to culture conversion, increased mortality during treatment, plasma C-reactive protein concentrations and sedimentation rate, broader spectrum of AT used, as well as higher incidence of adverse effects (sufficiently controlled with symptomatic treatment) were observed with higher degree of resistance. Contrary, the number of patients who achieved remission decreased. Rapid and precise identification of MDR-TB or XDR-TB strains using both classical and molecular-genetic testing is an essential tool for personalized drug treatment and prevention of resistance spread and worsening. Both tests should be used for correct diagnosis of resistant TB. Higher level of resistance required more aggressive therapeutic approach, associated with adverse effects and prolongation of the culture conversion time, as well as increased risk of relapse. Effective pharmacotherapy led to significant decrease of CRP levels in all groups of patients. The most frequent adverse effects of ATs - impairment of liver and kidney functions - were effectively managed by symptomatic treatment.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Mycobacterium tuberculosis/genética , Tuberculose Resistente a Múltiplos Medicamentos/microbiologia , Adulto , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , DNA Bacteriano/análise , Humanos , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Mycobacterium tuberculosis/isolamento & purificação , Fenótipo , Eslováquia/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/diagnóstico , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia
16.
Rev Inst Med Trop Sao Paulo ; 61: e29, 2019 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-31241658

RESUMO

Increased resistance to polymyxin in Klebsiella pneumoniae (ColRKP) has been observed. Molecular epidemiology, as well as the clinical impact of these difficult to treat pathogens need to be better characterized. We present the clinical outcomes of 28 patients infected by ColRKP in a tertiary hospital. Isolates with MIC >2 by Vitek 2 were confirmed by the microdilution broth test. Polymerase chain reaction (PCR) was performed for blaKPC, blaNDM, blaOXA-48 and blamcr-1 genes in the isolates, and Whole Genome Sequencing (WGS) was performed in six isolates. Seventeen (61%) patients were female and the mean age was 50 years old. In-hospital and 30-day mortality were 64% (18/28) and 53% (15/28), respectively. Central line-associated bloodstream infection in addition to bacteremia episodes due to other sources were the most frequent (61%). Mean APACHE and Charlson comorbidity index were 16 and 5, respectively. Twenty patients (71%) received at least one active drug and ten (35%) received two drugs: tigecycline 46% (13/28); amikacin 21% (6/28) and fosfomycin 3% (1 case). Twenty-six out of 28 tested cases were positive for blaKPC. Eight different clusters were identified. Four STs were detected (ST11, ST23, ST340, and ST437). Mutations on pmrA, arnB, udg, and yciM genes were present in all six isolates submitted to WGS; lpxMand mgrB mutations were also detected in all but one isolate. In conclusion, we observed resistance to polymyxin in severely ill patients mostly from intensive care units and/or immunosuppressed patients with high mortality rates in whom a diversity of ColRKP clusters was identified and might indicate selective pressure.


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Polimixinas/farmacologia , Adolescente , Brasil , Feminino , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Centros de Atenção Terciária
17.
Int J Food Microbiol ; 304: 49-57, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31154111

RESUMO

In this study, the antimicrobial resistance profiles of L. monocytogenes isolated from chicken meat in Fukuoka in 2017 were compared with the isolates of 2012. A total of 85 and 50 chicken meat samples, including different body parts, were collected from different supermarkets in Fukuoka in 2012 and 2017, respectively. Detection, isolation, identification, and characterization of L. monocytogenes were performed according to the conventional methods. Forty-five among 85 samples (53%) were positive for L. monocytogenes in 2012, while 12 among 50 samples in 2017 (24%) tested positive. One hundred fifty-three and 29 L. monocytogenes strains were isolated in 2012 and 2017, respectively. The serotypes of isolates in 2012 were 1/2a (21.5%), 1/2b (73.9%), 1/2c (1.5%), and 4b/4e (3.1%). In contrast, the 2017 isolates showed 1/2a (48.3%) and 1/2b (51.7%) serotypes. While all isolates in 2012 were positive for hlyA (listeriolysin O) in the PCR assay with hlyA primer set 7, only 17 hlyA positive isolates were seen in 2017. Moreover, 75 isolates with different ribotypes in 2012 and 29 isolates in 2017, respectively, were tested for antimicrobial susceptibility by broth microdilution for 18 different antimicrobial agents. Most of the 2012 and 2017 isolates displayed antimicrobial susceptibility. However, among the 2012 and 2017 isolates, 98.7% and 100% of the isolates were resistant to cefoxitin, 57.3% and 95.7% to fosfomycin, 72.0% and 82.6% to oxacillin, 8.0% and 17.4% to clindamycin, respectively. In addition, 2.7% of the isolates in 2012 were resistant to flomoxef and 4.3% of the isolates in 2017 to linezolid. Multidrug resistance (MDR) to 3 or more antimicrobials was observed in 35/75 (46.7%) isolates of 2012 and 19/23 (82.6%) in 2017. Detection of antimicrobial resistance (AMR) genes by PCR showed that the resistant isolates of 2012 were positive for mecA (96.3%) and ermC (83.3%), whereas the resistant isolates in 2017 screened positive for mecA (94.7%) and mefA (25.0%). Other cfxA, ermA, ermB, fosA, fosB, and fosC genes were absent in the PCR assay for any of the isolates. This study investigated for the first time the change in the L. monocytogenes contamination of chicken meat and antibiotic resistance of the isolated L. monocytogenes strains in Fukuoka, Japan, in the course of 5 years. Although the contamination rate of L. monocytogenes in 2017 was found to be lower than that in 2012, AMR of the isolates in 2017 was higher.


Assuntos
Antibacterianos/farmacologia , Galinhas/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Contaminação de Alimentos/análise , Listeria monocytogenes/efeitos dos fármacos , Listeria monocytogenes/genética , Carne/microbiologia , Animais , Microbiologia de Alimentos , Japão , Listeria monocytogenes/isolamento & purificação , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Sorogrupo
18.
Int J Food Microbiol ; 304: 68-74, 2019 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-31174037

RESUMO

Salmonella enterica subsp. enterica serotype Rissen is the predominant serotype found in Thai pork production and can be transmitted to humans through contamination of the food chain. This study was conducted to investigate the genetic relationships between serovar Rissen isolates from all levels of the pork production chain and evaluate the ability of the in silico antimicrobial resistance (AMR) genotypes to predict the phenotype of serovar Rissen. A total of 38 serovar Rissen isolates were tested against eight antibiotic agents by a disk diffusion method and the whole genomes of all isolates were sequenced to detect AMR genetic elements using the ResFinder database.A total of 86.84% of the isolates were resistant to tetracycline, followed by ampicillin (78.96%) and sulfonamide-trimethoprim (71.05%). Resistance to more than one antimicrobial agent was observed in 78.95% of the isolates, with the most common pattern showing resistance to ampicillin, chloramphenicol, streptomycin, sulfonamide-trimethoprim, and tetracycline. The results of genotypic AMR indicated that 89.47% of the isolates carried tet(A), 84.22% carried blaTEM-1B, 78.95% carried sul3, and 78.95% carried dfrA12. The genotypic prediction of phenotypic resistance resulted in a mean sensitivity of 97.45% and specificity of 75.48%. Analysis by core genome multilocus sequence typing (cgMLST) demonstrated that the Salmonella isolates from various sources and different locations shared many of the same core genome loci. This implies that serovar Rissen has infected every stage of the pork production process and that contamination can occur in every part of the production chain.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Contaminação de Alimentos/análise , Carne Vermelha/microbiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , Animais , Doenças Transmitidas por Alimentos/microbiologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Fenótipo , Salmonelose Animal/microbiologia , Salmonella enterica/isolamento & purificação , Análise de Sequência , Suínos , Doenças dos Suínos/microbiologia , Tailândia
19.
Nat Commun ; 10(1): 2763, 2019 06 24.
Artigo em Inglês | MEDLINE | ID: mdl-31235751

RESUMO

Multidrug resistant (MDR) Acinetobacter baumannii poses a growing threat to global health. Research on Acinetobacter pathogenesis has primarily focused on pneumonia and bloodstream infections, even though one in five A. baumannii strains are isolated from urinary sites. In this study, we highlight the role of A. baumannii as a uropathogen. We develop the first A. baumannii catheter-associated urinary tract infection (CAUTI) murine model using UPAB1, a recent MDR urinary isolate. UPAB1 carries the plasmid pAB5, a member of the family of large conjugative plasmids that represses the type VI secretion system (T6SS) in multiple Acinetobacter strains. pAB5 confers niche specificity, as its carriage improves UPAB1 survival in a CAUTI model and decreases virulence in a pneumonia model. Comparative proteomic and transcriptomic analyses show that pAB5 regulates the expression of multiple chromosomally-encoded virulence factors besides T6SS. Our results demonstrate that plasmids can impact bacterial infections by controlling the expression of chromosomal genes.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/patogenicidade , Infecções Relacionadas a Cateter/microbiologia , Plasmídeos/genética , Pneumonia Bacteriana/microbiologia , Infecções Urinárias/microbiologia , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/genética , Acinetobacter baumannii/isolamento & purificação , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções Relacionadas a Cateter/epidemiologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana Múltipla/genética , Perfilação da Expressão Gênica , Regulação Bacteriana da Expressão Gênica , Humanos , Camundongos , Pneumonia Bacteriana/epidemiologia , Proteômica , Estudos Retrospectivos , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo , Cateteres Urinários/efeitos adversos , Cateteres Urinários/microbiologia , Sistema Urinário/microbiologia , Infecções Urinárias/epidemiologia , Virulência/genética , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
20.
Vet Microbiol ; 233: 5-10, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31176412

RESUMO

This work aimed to determine the prevalence, diversity, antibiotic-resistance phenotype/genotype and virulence factors in staphylococci of farm-animals. Nasal samples of 117 farm-animals (calve: 72; lamb: 37; goat: 8) were collected from one slaughterhouse in La Rioja/Spain and cultured for staphylococci and methicillin-resistant Staphylococcus (MRS) recovery. Identification was performed by MALDI-TOF. Antimicrobial resistance phenotype/genotype was determined by susceptibility testing and specific PCRs. Molecular typing (spa-typing, multilocus-sequence-typing, agr-typing, SCCmec), and detection of 12 virulence genes and human Immune-evasive-cluster (IEC) genes were performed by PCR/sequencing in S. aureus. Two marker genes of arginine catabolic mobile element (ACME) were determined by PCR (USA300-MRSA detection). Staphylococci were identified in 50%, 54% and 21% of goat, lamb and calve samples, respectively. Among the 13 S. aureus isolates recovered, 11 were susceptible to all antimicrobials tested, and two were multidrug-resistant-MRSA [beta-lactams (blaZ, mecA), macrolides [(msr(A)/msr(B)] and fluoroquinolones]. The MSSA harboured either tst or enterotoxin genes, while the MRSA harboured the lukF/lukS-PV genes. Five sequence-types were detected. The two MRSA strains (from lamb and goat) were typed as t5173/ST8/agr-I/SCCmec-IVa/ACME-positive, corresponding to USA300 clone, and were IEC-B-positive. Among the 47 coagulase-negative staphylococci (CoNS), six species were identified, predominating S. simulans (n = 25) and S. sciuri (n = 11). Fifty-three percent of CoNS showed resistance to at least one antimicrobial agent (six multidrug-resistant strains), and the following resistance phenotypes/genotypes were detected: streptomycin [27.6%; ant(6)-Ia, str], tetracycline [23.4%; tet(M), tet(L), tet(K)], clindamycin [19.1%; lnu(A), vgaA], erythromycin [10.6%; erm(C), msr(A)/msr(B)], chloramphenicol (8.5%; fexA), tobramycin (6.4%), penicillin-cefoxitin (4.3%; blaZ, mecA), and SXT (2.1%). The detection of the MRSA-USA300 lineage in food animals is worrisome and should be further monitored.


Assuntos
Portador Sadio/veterinária , Reservatórios de Doenças/veterinária , Variação Genética , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus/classificação , Fatores de Virulência/genética , Animais , Antibacterianos/farmacologia , Portador Sadio/microbiologia , Reservatórios de Doenças/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Genes Bacterianos , Genótipo , Cabras/microbiologia , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Nariz/microbiologia , Reação em Cadeia da Polimerase , Prevalência , Carne Vermelha/microbiologia , Ovinos/microbiologia , Espanha/epidemiologia , Infecções Estafilocócicas/epidemiologia , Staphylococcus/efeitos dos fármacos , Tetraciclina/farmacologia
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