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1.
J Med Microbiol ; 72(6)2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37294294

RESUMO

Introduction. Carbapenemase-producing Enterobacteriaceae (CPE) have emerged as a global threat to public health and clinical practice.Hypothesis/Gap Statement. In Thailand, reports describing CPEs carrying bla NDM and bla OXA-48-like genes have been increasing recently; however, data on detailed plasmid analysis and temporal shift of sequence type and carbapenemase type are limited.Aim. In this study, we analysed whole-genome sequencing (WGS) data of clinically isolated carbapenemase-producing Klebsiella pneumoniae (CPKP) to reveal the molecular epidemiology of CPKP in a tertiary-care hospital in Bangkok, Thailand.Methodology. Seventy-seven non-duplicated CPKP isolates collected during 2013-2016 were examined for their drug-resistance genes, sequence types and phylogenetic relationships.Results. All the tested isolates possessed carbapenemase gene(s), and the major type of carbapenemase gene in 2014-2015 was bla NDM-1, whereas isolates in 2016 harboured more bla OXA-232 than bla NDM-1. Other carbapenemase gene variants, such as bla NDM-4, bla NDM-5, bla OXA-48, bla OXA-181 and bla IMP-14 were detected in some CPKP isolates. Furthermore, this study revealed that CPKP co-harbouring two genes, bla NDM-1 and bla OXA-232 or bla OXA-181, emerged during this period. Notably, such isolates co-carrying the two carbapenemase genes emerged in three different sequence types, even in a single hospital, and then spread clonally. The WGS of CPKP revealed a temporal shift of the predominant carbapenemase genes from bla NDM-1 to bla OXA-232 along with a variation in other carbapenemase gene types within a span of 4 years.Conclusion. Our findings suggest that a substantial change in CPE types occurred in Thailand and potentially in Southeast Asian countries.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Humanos , Klebsiella pneumoniae/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Tailândia/epidemiologia , Filogenia , Infecções por Enterobacteriaceae/epidemiologia , beta-Lactamases/genética , Proteínas de Bactérias/genética , Testes de Sensibilidade Microbiana
2.
J Clin Microbiol ; 60(12): e0108022, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36445367

RESUMO

Despite frequent identification of plasmids carrying carbapenemase genes, the transfer of plasmids carrying carbapenemase genes is not well recognized in clinical settings because of technical limitations. To investigate the detailed mechanisms of the spread of carbapenem-resistant Enterobacteriaceae (CRE), we performed multifaceted genomic surveillance of CRE isolates in Thailand and analyzed their plasmidome. We analyzed 371 Enterobacteriaceae isolates carrying blaNDM-1 and 114 Enterobacteriaceae isolates carrying blaNDM-5 obtained from clinical samples of 473 patients in 11 representative hospitals located in six provinces in Thailand between 2012 and 2017. The complete structures of plasmids carrying blaNDM and chromosomal phylogeny were determined by combining Southern blotting hybridization analysis and our previously performed whole-genome short-read sequencing data. Dissemination of the blaNDM-5 gene among the Enterobacteriaceae isolates in Thailand was mainly owing to the nationwide clonal spread of Escherichia coli ST410 and regional clonal spreads of Escherichia coli ST361 and ST405. Analysis of blaNDM-1-carrying isolates revealed nationwide dissemination of two specific plasmids and nationwide clonal dissemination of Klebsiella pneumoniae ST16 accompanied with regional disseminations of three distinctive K. pneumoniae clones (ST231, ST14, and ST147) with different plasmids. Dissemination of CRE carrying blaNDM in Thailand is mainly based on nationwide clonal expansions of E. coli ST410 carrying blaNDM-5 and K. pneumoniae ST16 carrying blaNDM-1, nationwide dissemination of two distinctive plasmids carrying blaNDM-1, and accumulation of clonal expansions in regional areas. Although the overuse of antibiotics can promote CRE dissemination, the limited variety of transmitters highlights the importance of preventing horizontal dissemination among patients.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae , Humanos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Escherichia coli/genética , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Tailândia/epidemiologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Enterobacteriaceae/genética , Plasmídeos/genética , Klebsiella pneumoniae/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
3.
JAC Antimicrob Resist ; 4(4): dlac084, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35983103

RESUMO

Background: Klebsiella pneumoniae ST258 and ST11 carrying bla KPC are among the most widespread carbapenem-resistant K. pneumoniae strains worldwide. Our carbapenem-resistant Enterobacteriaceae surveillance in Thailand revealed a nationwide dissemination of K. pneumoniae ST16 isolates carrying bla NDM-1 and bla OXA-232. Objectives: To analyse the genomic details of this nationwide dissemination by focusing on plasmids and virulence factors. Methods: Using WGS data of 119 K. pneumoniae ST16 isolates carrying bla NDM-1 obtained in our previous surveillance study, clonality of chromosomes and plasmids of the isolates with carriage of virulence factors was evaluated. Results: Of the 119 isolates, 111 carried plasmid pKP151_NDM1, and all 104 isolates harbouring bla OXA-232 carried plasmid pKP151_OXA232. These 104 K. pneumoniae ST16 isolates showing chromosomal clonality possessed both pKP151_NDM1 and pKP151_OXA232, demonstrating clonal dissemination of K. pneumoniae ST16 with these plasmids. The isolates had essentially similar virulence factors as those of K. pneumoniae ST16 clones carrying bla KPC, which were recently reported as highly invasive clones in Brazil. Conclusions: The potential global dissemination of these invasive clones with resistance to several antibiotics highlights the importance of appropriate monitoring and strict standard precautions.

4.
Microbiol Spectr ; 10(4): e0058722, 2022 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-35916525

RESUMO

The spread of New Delhi metallo-ß-lactamase (NDM)-producing Enterobacterales represents a public health risk. The horizontal transfer of plasmids encoding the NDM gene, blaNDM, usually mediates its spread to other bacteria within the family. In contrast, Enterobacterales with a chromosome-located blaNDM is rarely reported. The phenotypic differences between chromosome- and plasmid-located carbapenemase genes are poorly understood. To determine the significance in terms of the location of drug resistance genes, we examined carbapenemase activity and stability of chromosome- and plasmid-located blaNDM. Escherichia coli M719 possessing both chromosomes- and plasmid-located blaNDM genes was used as a wild-type strain (WT) for the construction of mutants, ΔpblaNDM and ΔcblaNDM, wherein chromosome- or plasmid-located blaNDM, was knocked out, respectively. The mutant ΔpblaNDM showed lower hydrolyzing activity against imipenem and gene expression than the WT or ΔcblaNDM mutant. The MICs of both mutant strains were still above the breakpoint of imipenem and meropenem. Moreover, the chromosome-located blaNDM gene was stable for at least 30 days in the absence of antimicrobial pressure, whereas the ΔcblaNDM mutant lost blaNDM to 87% at 30 days compared to that of the initial inoculum. Organisms harboring the plasmid-located carbapenemase genes were found to provide a higher level of carbapenem resistance than those with chromosome-located genes. However, the latter organisms with chromosomal carbapenemase genes exhibited more stable carbapenem resistance than did the former ones. In summary, chromosomally located carbapenemase genes require further monitoring and more attention should be paid to them. IMPORTANCE Carbapenem-resistant Enterobacterales (CRE) carrying blaNDM have spread worldwide since they were first reported in 2009. Many studies using whole-genome sequencing have identified the genetic structures, plasmid scaffolds of blaNDM, and mechanisms of spread via horizontal transfer. Chromosome-located blaNDM and integration mechanisms from plasmids have rarely been reported, and their significance is not fully understood. Here, we showed that the chromosome-located blaNDM was associated with lower levels of carbapenem resistance and carbapenemase activity than the plasmid-located blaNDM. However, it conferred carbapenem resistance above the breakpoints and the loss of chromosome-located blaNDM was not observed in the absence of antibiotic pressure. This study suggests that CRE strains carrying chromosome-located blaNDM may persist in clinical and environmental settings for a long period even without antibiotic pressure and need to be monitored along with plasmid-located blaNDM.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Cromossomos , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Humanos , Imipenem , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética
6.
J Antimicrob Chemother ; 76(6): 1448-1454, 2021 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-33758942

RESUMO

BACKGROUND: Carbapenemase-producing Enterobacterales (CPE) are spreading in hospitals, environment and retail foods in Yangon, Myanmar. OBJECTIVES: To investigate whether CPE colonize healthy individuals living in Yangon and whether clinical-related strains are spreading in the community. METHODS: CPE was isolated from faecal samples obtained from healthy Japanese residents of Yangon with no history of hospitalization. Isolates were subjected to WGS using short- and long-read sequencers and compared with those previously isolated in Yangon. RESULTS: Six Escherichia coli strains harbouring blaNDM-1 or blaNDM-5 belonging to five different STs-ST10, ST38, ST48, ST410 and ST8453-were isolated from 69 volunteers. The ST38 isolates were related to those previously isolated from retail food in Yangon. The ST410 and ST8453 isolates were highly related to previous Yangon isolates including those of clinical and food origins. CONCLUSIONS: The analysis suggested the acquisition of blaNDM-positive E. coli, which are disseminating in a clinical setting and through retail foods, by healthy residents in Yangon.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Antibacterianos/farmacologia , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Humanos , Japão/epidemiologia , Testes de Sensibilidade Microbiana , Mianmar/epidemiologia , beta-Lactamases/genética
8.
RSC Adv ; 11(27): 16530-16536, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-35479124

RESUMO

The ionic conductivity of Li6Y(BO3)3 (LYBO) was enhanced by the substitution of tetravalent ions (Zr4+ and Ce4+) for Y3+ sites through the formation of vacancies at the Li sites, an increase in compact densification, and an increase in the Li+-ion conduction pathways in the LYBO phase. As a result, the ionic conductivity of Li5.875Y0.875Zr0.1Ce0.025(BO3)3 (ZC-LYBO) reached 1.7 × 10-5 S cm-1 at 27 °C, which was about 5 orders of magnitude higher than that of undoped Li6Y(BO3)3. ZC-LYBO possessed a large electrochemical window and was thermally stable after cosintering with a LiNi1/3Mn1/3Co1/3O2 (NMC) positive electrode. These characteristics facilitated good reversible capacities in all-solid-state batteries for both NMC positive electrodes and graphite negative electrodes via a simple cosintering process.

9.
Environ Microbiol Rep ; 12(5): 548-554, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32776437

RESUMO

Shewanella sp., the progenitors of blaOXA-48 -like genes are increasingly reported with the possession of different blaOXA-48 -like variants. This study aims to characterize blaOXA-731 , a new variant of a blaOXA-48 -like gene identified in Shewanella sp. isolated from the aquatic environment in Myanmar. Phylogenetic analysis of the blaOXA-731 sequence with other blaOXA-48 -like variants showed that it has the highest nucleotide identity of 86.09% with blaOXA-48 . However, the active site motifs in OXA-731 were 100% identical to that in OXA-48. Whole-genome sequencing analysis showed that blaOXA-731 is not surrounded by any mobile genetic elements. The genetic context of blaOXA-731 was found as similar to other blaOXA-48 -like genes previously identified in Shewanella sp. S1 nuclease pulsed-field gel electrophoresis followed by Southern blotting confirmed the location of blaOXA-731 in the chromosome of the Shewanella genome. Cloning and expression studies showed that OXA-731 has ß-lactamase activity similar to OXA-48 and OXA-181, but it has no significant carbapenemase activity. Our results showed the significance of blaOXA-48 -like-carrying Shewanella sp. in the spreading of blaOXA-48 -like genes in the community.


Assuntos
Proteínas de Bactérias/genética , Água Potável/microbiologia , Shewanella/enzimologia , beta-Lactamases/genética , Sequência de Aminoácidos , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Cromossomos Bacterianos/enzimologia , Cromossomos Bacterianos/genética , Testes de Sensibilidade Microbiana , Mianmar , Filogenia , Alinhamento de Sequência , Shewanella/efeitos dos fármacos , Shewanella/genética , Shewanella/isolamento & purificação , beta-Lactamases/metabolismo
10.
Int J Antimicrob Agents ; 55(3): 105905, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31991221

RESUMO

BACKGROUND: Limited treatment options complicate management of infections with New Delhi metallo-ß-lactamase (NDM)-producing organisms. The efficacy of combination therapy with meropenem (MEM) and cefmetazole (CMZ) was assessed against NDM-producing Enterobacteriaceae. MATERIALS AND METHODS: Twelve Escherichia coli clinical isolates harbouring blaNDM-1 and a positive control E. coli BAA-2469 harbouring blaNDM-1 were studied. Minimum inhibitory concentrations (MICs) of MEM, ertapenem (ERT) and CMZ were determined by broth microdilution. Checkerboard and time-kill assays were performed to confirm the in vitro efficacy of the MEM/CMZ combination. Scanning electron microscopy, kinetic studies and whole-genome sequence analysis were used to determine the antimicrobial resistance mechanisms. RESULTS: MICs of MEM, ERT and CMZ in monotherapy ranged from 8 to 32, 16 to 128, and 32 to 512 µg/mL, respectively. In the checkerboard assay, MEM/ERT resulted in no synergy, whereas MEM/CMZ showed a synergistic effect in all the tested isolates. Furthermore, the MIC of MEM in combination decreased by 2- to 8-fold compared with that of MEM alone. The time-kill study revealed a bactericidal effect in 4 of 13 isolates at 24 h. Scanning electron microscopy showed spheroidisation of the bacterial cell in the MEM/CMZ combination; this was not observed in single antibiotic conditions. Kinetic studies indicated CMZ was a better antagonist for NDM-1 than ERT. Whole-genome sequence analysis did not reveal any explainable differences between isolates susceptible and those non-susceptible to combination therapy. CONCLUSION: In vitro studies showed the potential effectiveness of MEM/CMZ combination therapy against NDM-producing organisms.


Assuntos
Antibacterianos/farmacologia , Cefmetazol/farmacologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Meropeném/farmacologia , Antibacterianos/uso terapêutico , Cefmetazol/uso terapêutico , Quimioterapia Combinada , Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Ertapenem/farmacologia , Humanos , Meropeném/uso terapêutico , beta-Lactamases/biossíntese
11.
J Glob Antimicrob Resist ; 21: 195-199, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31627024

RESUMO

OBJECTIVES: To analyse plasmids carrying blaIMP-6 in Klebsiella pneumoniae isolates obtained from multicentre carbapenem-resistant Enterobacteriaceae surveillance. METHODS: Plasmids harbouring blaIMP-6 were characterised by the whole-genome sequencing of four Klebsiella pneumoniae isolates carrying blaIMP-6, and compared with the pKPI-6 plasmid, which is widespread in western Japan, through pulsed-field gel electrophoresis, Southern blotting, bacterial conjugation, and qPCR. RESULTS: Whole-genome sequencing analysis revealed that three of the four isolates carried approximately 50 kbp plasmids similar to the pKPI-6 plasmid; however, one isolate carried a 250 kbp plasmid harbouring blaIMP-6 (pE196_IMP6). So far, all of the reported plasmids carrying blaIMP-6 were similar to the pKPI-6 plasmid, and this plasmid was a novel blaIMP6-carrier. The size and transferability of this plasmid was confirmed by Southern hybridisation and conjugation experiments. It was demonstrated that the generation of plasmid pE196_IMP6 was due to an intramolecular transposition mediated by IS26, and a homologous recombination between plasmids pKPI-6 and pE013 that was obtained from another carbapenem-resistant Enterobacteriaceae isolate in this analysis. As a result of co-integration with pE013, pE196_IMP6 acquired six additional pairs of type II toxin-antitoxin systems that pKPI-6 does not carry. Transcription of all of the toxin-antitoxin systems were confirmed in an isolate carrying pE196_IMP6 by qPCR. CONCLUSIONS: This study detected a novel plasmid carrying blaIMP-6, and revealed the origin of this plasmid. Toxin-antitoxin system acquisition could enable pE196_IMP6 maintenance persistently through successions, even without selection pressure by the clinical usage of antimicrobials, generating broad dissemination and longer carbapenem-resistant Enterobacteriaceae colonisation duration in patients.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Klebsiella pneumoniae , Humanos , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , beta-Lactamases/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Carbapenêmicos/farmacologia , Genômica , Japão , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética
12.
Sci Rep ; 9(1): 14455, 2019 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-31595007

RESUMO

The spread of carbapenemase-producing Enterobacteriaceae (CPE) poses a serious threat to clinical practice and public health. These bacteria are present both in clinical settings and non-clinical environments. The presence of CPE in food stuffs has been reported, but sporadically so. Here, we screened for CPE in meat, seafood, and vegetable samples from local markets of Yangon, Myanmar. We obtained 27 CPE isolates from 93 food samples and identified 13 as Escherichia coli, six as Klebsiella pneumoniae, seven as Enterobacter cloacae complex, and one as Serratia marcescens. All except the E. cloacae complex harboured the carbapenemase genes blaNDM-1 or blaNDM-5, while all Enterobacter isolates carried the carbapenemase gene blaIMI-1. The blaIMI-1 gene was located in putative mobile elements EcloIMEX-2, -3, or -8. Using multi-locus sequence typing, E. coli, K. pneumoniae, and E. cloacae complex isolates were classified into 10, six, and five different sequence types, respectively. Our results demonstrate that diverse organisms with various carbapenemase genes are widespread in the market foods in Yangon, highlighting the need for promoting proper food hygiene and effective measures to prevent further dissemination.


Assuntos
Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Microbiologia de Alimentos , beta-Lactamases/metabolismo , Animais , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Contaminação de Alimentos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Carne/microbiologia , Mianmar , Verduras/microbiologia , beta-Lactamases/genética
13.
J Med Microbiol ; 68(12): 1707-1715, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31661049

RESUMO

Purpose. Carbapenemase-producing Enterobacteriaceae (CPE) have become a global concern and a serious threat to human health due to their resistance to multiple antibiotics. In this study, we identified and characterized CPE for the first time in Malawi, southeastern Africa.Methodology. We investigated the possible presence of carbapenemases among a collection of 200 ceftriaxone-nonsusceptible Gram-negative clinical isolates obtained from five Malawian hospitals between January 2016 and December 2017, using both phenotypic and genotypic tests. Molecular typing of CPE was done by PFGE, multilocus sequence typing (ST) or phylogenetic grouping. Resistant plasmids were characterized by S1 PFGE, Southern blotting and conjugation assays.Results. Out of 200 isolates, we detected 16 (8 %) CPE of which all originated from one referral hospital, Kamuzu Central Hospital, in the Central part of Malawi. Of 16 isolates, seven Klebsiella pneumoniae ST340/CC258 carried bla KPC-2, two Escherichia coli ST636 (phylogroup B2) carried bla NDM-5, six E. coli ST617 (phylogroup A) and one Klebsiella variicola carried bla OXA-48. All carbapenemases were plasmid-encoded, but only bla NDM-5-carrying plasmids could be conjugated. Most isolates co-harboured other ß-lactamases and consequently exhibited a wider spectrum of resistance to commonly used antibiotics. We observed indistinguishable genetic profiles between strain types, despite originating from different wards, suggesting acquisition during admission and intra-hospital spread.Conclusion. This report strongly suggests a probable existence of highly resistant various types of CPE organisms in Malawi including KPC-2-producing K. pneumoniae ST340/CC258, a known high-risk epidemic lineage.


Assuntos
Proteínas de Bactérias/biossíntese , Enterobacteriaceae/isolamento & purificação , beta-Lactamases/biossíntese , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Genoma Bacteriano , Humanos , Testes de Sensibilidade Microbiana
14.
Front Microbiol ; 10: 149, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30800104

RESUMO

Colistin is used as an alternative therapeutic for carbapenemase-producing Enterobacteriaceae (CPE) infections which are spreading at a very high rate due to the transfer of carbapenemase genes through mobile genetic elements. Due to the emergence of mcr-1, the plasmid-mediated colistin resistance gene, mcr-1-positive Enterobacteriaceae (MCRPEn) pose a high risk for the transfer of mcr-1-carrying plasmid to CPE, leading to a situation with no treatment alternatives for infections caused by Enterobacteriaceae possessing both mcr-1 and carbapenemase genes. Here, we report the application of PCR-dipstick-oriented surveillance strategy to control MCRPEn and CPE by conducting the PCR-dipstick technique for the detection of MCRPEn and CPE in a tertiary care hospital in Thailand and comparing its efficacy with conventional surveillance method. Our surveillance results showed a high MCRPEn (5.9%) and CPE (8.7%) carriage rate among the 219 rectal swab specimens examined. Three different CPE clones were determined by pulsed-field gel electrophoresis (PFGE) whereas only two MCRPEn isolates were found to be closely related as shown by single nucleotide polymorphism-based phylogenetic analysis. Whole genome sequencing (WGS) and plasmid analysis showed that MCRPEn carried mcr-1 in two plasmids types-IncX4 and IncI2 with ~99% identity to the previously reported mcr-1-carrying plasmids. The identification of both MCRPEn and CPE in the same specimen indicates the plausibility of plasmid-mediated transfer of mcr-1 genes leading to the emergence of colistin- and carbapenem-resistant Enterobacteriaceae. The rapidity (<2 h) and robust sensitivity (100%)/specificity (~99%) of PCR-dipstick show that this specimen-direct screening method could aid in implementing infection control measures at the earliest to control the dissemination of MCRPEn and CPE.

15.
Artigo em Inglês | MEDLINE | ID: mdl-30530602

RESUMO

The spread of carbapenemase-producing Enterobacteriaceae (CPE), contributing to widespread carbapenem resistance, has become a global concern. However, the specific dissemination patterns of carbapenemase genes have not been intensively investigated in developing countries, including Myanmar, where NDM-type carbapenemases are spreading in clinical settings. In the present study, we phenotypically and genetically characterized 91 CPE isolates obtained from clinical (n = 77) and environmental (n = 14) samples in Yangon, Myanmar. We determined the dissemination of plasmids harboring genes encoding NDM-1 and its variants using whole-genome sequencing and plasmid analysis. IncFII plasmids harboring blaNDM-5 and IncX3 plasmids harboring blaNDM-4 or blaNDM-7 were the most prevalent plasmid types identified among the isolates. The IncFII plasmids were predominantly carried by clinical isolates of Escherichia coli, and their clonal expansion was observed within the same ward of a hospital. In contrast, the IncX3 plasmids were found in phylogenetically divergent isolates from clinical and environmental samples classified into nine species, suggesting widespread dissemination of plasmids via horizontal transfer. Half of the environmental isolates were found to possess IncX3 plasmids, and this type of plasmid was confirmed to transfer more effectively to recipient organisms at a relatively low temperature (25°C) compared to the IncFII plasmid. Moreover, various other plasmid types were identified harboring blaNDM-1, including IncFIB, IncFII, IncL/M, and IncA/C2, among clinical isolates of Klebsiella pneumoniae or Enterobacter cloacae complex. Overall, our results highlight three distinct patterns of the dissemination of blaNDM-harboring plasmids among CPE isolates in Myanmar, contributing to a better understanding of their molecular epidemiology and dissemination in a setting of endemicity.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Infecções por Enterobacteriaceae/epidemiologia , Plasmídeos/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana/genética , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/genética , Enterobacter cloacae/isolamento & purificação , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Mianmar/epidemiologia , Sequenciamento Completo do Genoma
16.
Artigo em Inglês | MEDLINE | ID: mdl-30323033

RESUMO

We report here Klebsiella pneumoniae strains carrying chromosomal blaNDM-1 in Thailand. The genomes of these two isolates include a 160-kbp insertion containing blaNDM-1, which is almost identical to that in the IncHI1B-like plasmid. Further analysis indicated that IS5-mediated intermolecular transposition and Tn3 transposase-mediated homologous recombination resulted in the integration of blaNDM-1 into the chromosome from an IncHI1B-like plasmid. The spread of this type of carbapenem-resistant Enterobacteriaceae may threaten public health and warrants further monitoring.


Assuntos
Cromossomos Bacterianos/química , Genoma Bacteriano , Klebsiella pneumoniae/genética , Mutagênese Insercional , Plasmídeos/metabolismo , beta-Lactamases/genética , Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Mapeamento Cromossômico , Elementos de DNA Transponíveis , Expressão Gênica , Recombinação Homóloga , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Plasmídeos/química , Tailândia/epidemiologia , Transposases/genética , Transposases/metabolismo , beta-Lactamases/metabolismo
17.
Sci Rep ; 8(1): 15689, 2018 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-30356169

RESUMO

The spread of carbapenemase-producing Enterobacteriaceae (CPE) is an increasing global public health concern. The development of simple and reliable methods for CPE detection is required in the clinical setting. This study aimed to establish a dual-wavelength measurement method using an ultraviolet-visible spectrophotometer to rapidly quantify imipenem hydrolysis in bacterial cell suspensions. The hydrolytic activities of 148 strains including various CPE strains (Escherichia coli, Klebsiella pneumoniae, Enterobacter cloacae, and Enterobacter aerogenes containing the blaIMP, blaKPC, blaNDM, blaOXA, and blaVIM genes) were measured and analysed. A cut-off value was obtained for differentiation between CPE and non-CPE strains, and the method had high sensitivity (100%) and specificity (100%) within 60 min. Our system has potential clinical applications in detecting CPE.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/química , Enterobacteriáceas Resistentes a Carbapenêmicos/enzimologia , Espectrofotometria Ultravioleta/métodos , Absorção Fisico-Química , Antibacterianos/química , Proteínas de Bactérias/análise , Infecções por Enterobacteriaceae/diagnóstico , Hidrólise , Imipenem/química , Meropeném/química , Curva ROC , Sensibilidade e Especificidade , Estatísticas não Paramétricas , Resistência beta-Lactâmica , beta-Lactamases/análise
18.
J Med Microbiol ; 67(9): 1221-1224, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30074471

RESUMO

An NDM-5-producing Klebsiella pneumoniae ST147 strain was isolated from a Japanese patient who had not travelled abroad in at least 5 years. Whole-genome sequencing revealed a genomic rearrangement in an FII plasmid harbouring blaNDM-5 due to the replicative transposition of IS26. A hypothetical structure was proposed for its ancestral plasmid, and comparative genomic analysis of the plasmid suggested the dissemination of structurally similar plasmids harbouring blaNDM-5 in Asian and Middle Eastern countries.


Assuntos
Proteínas de Bactérias/genética , Elementos de DNA Transponíveis , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Plasmídeos/genética , beta-Lactamases/genética , Adulto , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Humanos , Japão , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Plasmídeos/metabolismo , beta-Lactamases/metabolismo
19.
Diabetol Int ; 9(3): 179-188, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30603365

RESUMO

AIM: We developed a novel estimation method for hemoglobin A1c (HbA1c) in type 2 diabetes (T2D) patients with end-stage renal disease (ESRD). This method is based on the glycated albumin (GA) level. METHODS: Of the 788 Japanese patients with T2D included in this study, 545 had normal renal function (NRF group) and 243 had ESRD. Oral glucose tolerance tests (OGTTs) were performed in 80 subjects. The variables GA, body mass index (BMI), hemoglobin (Hb), and estimated glomerular filtration rate (eGFR) were significantly associated with the GA-to-HbA1c ratio and were used to determine the estimated HbA1c (eHbA1c). One method of estimating HbA1c involved dividing GA by the GA-to-HbA1c ratio predicted from the estimated regression equation; the estimated HbA1c obtained in this manner was denoted eHbA1c-1. RESULTS: eHbA1c-1 (%) = GA × [4.688 - 18.833 × GA-1 - 0.015 × BMI - 0.037 × Hb (- 0.002 × eGFR for patients without ESRD)]-1; adjusted R 2 = 0.676 for actual HbA1c. The sensitivity of eHbA1c-1 was better than that of GA for diabetes diagnosis using the 75-g OGTT. There were no differences in the slope of eHbA1c-1 versus GA and the variance of eHbA1c-1 between the ESRD and NRF groups. eHbA1c-1 was not associated with Hb, erythropoiesis-stimulating agent use, or ESRD concomitance. CONCLUSIONS: eHbA1c-1 may be a useful parameter for estimating HbA1c in T2D patients with ESRD.

20.
PLoS One ; 12(9): e0184720, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28910381

RESUMO

The bacterial enzyme New Delhi metallo-ß-lactamase hydrolyzes almost all ß-lactam antibiotics, including carbapenems, which are drugs of last resort for severe bacterial infections. The spread of carbapenem-resistant Enterobacteriaceae that carry the New Delhi metallo-ß-lactamase gene, blaNDM, poses a serious threat to public health. In this study, we genetically characterized eight carbapenem-resistant Escherichia coli isolates from a tertiary care hospital in Yangon, Myanmar. The eight isolates belonged to five multilocus-sequence types and harbored multiple antimicrobial-resistance genes, resulting in resistance against nearly all of the antimicrobial agents tested, except colistin and fosfomycin. Nine plasmids harboring blaNDM genes were identified from these isolates. Multiple blaNDM genes were found in the distinct Inc-replicon types of the following plasmids: an IncA/C2 plasmid harboring blaNDM-1 (n = 1), IncX3 plasmids harboring blaNDM-4 (n = 2) or blaNDM-7 (n = 1), IncFII plasmids harboring blaNDM-4 (n = 1) or blaNDM-5 (n = 3), and a multireplicon F plasmid harboring blaNDM-5 (n = 1). Comparative analysis highlighted the diversity of the blaNDM-harboring plasmids and their distinct characteristics, which depended on plasmid replicon types. The results indicate circulation of phylogenetically distinct strains of carbapenem-resistant E. coli with various plasmids harboring blaNDM genes in the hospital.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/classificação , Plasmídeos/genética , Resistência beta-Lactâmica , beta-Lactamases/genética , Carbapenêmicos/farmacologia , DNA Bacteriano/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Proteínas de Escherichia coli/genética , Evolução Molecular , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Mianmar , Filogenia , Análise de Sequência de DNA/métodos
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