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1.
Opt Express ; 30(15): 25995-26005, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236798

RESUMO

Hyperspectral imaging that detects 3D spectra-spatial information has been used in a wide range of applications. Among reported techniques, multiplexed spectral imaging with a single-pixel detector provides as a photon-efficient and low-cost implementation; however, the previous spectral modulation schemes are mostly complicated and sacrifice the imaging speed. Here, we propose a fast and compact hyperspectral single-pixel imaging technique based on programmable chromatic illumination. A multi-wavelength LED array modulated by independent carriers achieves stable and accurate spectral modulation up to MHz in a frequency-division multiplexed manner, hence allowing the full use of the spatial light modulation speed. Additionally, we propose a multi-channel deep convolutional autoencoder network to reconstruct hyperspectral data from highly-compressed 1D measurement. Experimental reconstructions of 12 spectral channels and 64 × 64 pixels are demonstrated for dynamic imaging at 12 fps image rate. The proposed imaging scheme is highly extensible to a wide spectrum range, and holds potential for portable spectral imagers in low-light or scattering applications.

2.
J Basic Microbiol ; 61(3): 219-229, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33555043

RESUMO

Multi-replicon plasmids harboring the IncpA1763-KPC replicon together with other replicons are being increasingly reported among Enterobacteriaceae species. However, plasmids with single IncpA1763-KPC replicons are poorly studied as a different incompatibility (Inc) group, despite their rise in appearance in some strains. IncpA1763-KPC plasmids, pA1763-KPC, and p427113-2, from two clinical Klebsiella pneumoniae isolates were fully sequenced by high-throughput genome sequencing. Linear structural comparisons of IncpA1763-KPC backbone region were made between these two plasmids and six arbitrarily selected representative IncpA1763-KPC plasmids sequenced previously. A further detailed genomic comparison was carried out between plasmids pA1763-KPC, p427113-2, and pFB2.2, which show high homology across the backbone sequence to one another. Among all sequenced IncpA1763-KPC plasmids considered in this study, plasmids pA1763-KPC and p427113-2 showed the most complete IncpA1763-KPC backbones. These were composed of the IncpA1763-KPC replicon (repAIncpA1763-KPC and its iterons), the 5.6-kb IncpA1763-KPC -type maintenance region, the 27.7-kb IncFIIK -type maintenance region, and the 36.6-kb IncFIIK -type conjugal transfer regions. Compared with pA1763-KPC or p427113-2, the backbone regions of the other analyzed IncpA1763-KPC plasmids had gradually undergone different deletions or truncations, but shared small and core IncpA1763-KPC backbones including the IncpA1763-KPC replicon, IncpA1763-KPC -type maintenance region, and residual IncFIIK -type maintenance region. Accessory modules integrated into IncpA1763-KPC backbones included the multidrug-resistant module blaKPC-2 region in pA1763-KPC, the metal-resistance modules ars region together with ncr region in pFB2.2 and sil in pKPN-9a0d, the ISKpn14-to-IS26 region in p427113-2, and other non-resistance region in the respective plasmids. This detailed comparative genomics analysis of IncpA1763-KPC plasmids provides a deep insight into their diversification and evolution.


Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Plasmídeos/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Escherichia coli/genética , Genoma Bacteriano/genética , Genômica/métodos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Replicon/genética
3.
J Antimicrob Chemother ; 75(8): 2093-2100, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32395746

RESUMO

OBJECTIVES: To dissect genomic features of IncpRBL16 plasmids from Pseudomonas. METHODS: An extensive genomic comparison was applied to all 17 available sequenced IncpRBL16 plasmids, including 8 sequenced in this study and another 2 sequenced in two of our previous studies. RESULTS: Conserved IncpRBL16 backbone markers repAIncpRBL16 together with its iterons, parB2-parA, che, pil and ter were present in all 17 plasmids. At least 18 regions or sites across IncpRBL16 genomes exhibited major modular differences, including insertion of accessory modules, deletion of backbone regions surrounding insertion sites and substitution of multiple-gene backbone regions. Ten plasmids carried a sole IncpRBL16 replicon, while exogenous acquisition of an auxiliary replicon (located in an accessory module) besides the primary IncpRBL16 replicon was observed in each of the remaining seven plasmids. The 17 IncpRBL16 plasmids carried at least 71 different accessory modules, notably including Tn1403-related regions, Tn7-family transposons, Tn6571-family transposons, integrative and conjugative elements, and integrative and mobilizable elements. There were a total of 40 known resistance genes, which were involved in resistance to 15 categories of antibiotics and heavy metals, notably including blaIMP-9, blaIMP-45, blaVIM-2, blaDIM-2, blaOXA-246, blaPER-1, aphA and armA. CONCLUSIONS: Different IncpRBL16 plasmids contain different profiles of accessory modules and thus diverse collections of resistance genes. To the best of our knowledge, this is the first report of fully sequenced blaOXA-246-carrying (p12939-PER) and blaPER-1-carrying (p12939-PER and pA681-IMP) IncpRBL16 plasmids and also that of 14 novel (first identified in this study) and additionally 31 newly named (first designated in this study, but with previously determined sequences) mobile elements.


Assuntos
Farmacorresistência Bacteriana Múltipla , beta-Lactamases , Plasmídeos/genética , Pseudomonas/genética , Replicon , beta-Lactamases/genética
4.
Artigo em Inglês | MEDLINE | ID: mdl-30602516

RESUMO

Here, we report a multidrug-resistant hypervirulent Klebsiella pneumoniae (MDR-HvKP) strain of sequence type 23 (ST23) with a rare hybrid plasmid harboring virulence genes and blaCTX-M-24, and we analyze the genetic basis for relationship between genotypes and MDR-hypervirulence phenotypes. Further analysis indicates that the hybrid plasmid is formed by IS903D-mediated intermolecular transposition of the blaCTX-M-24 gene into the virulence plasmid. The emergence of MDR-HvKP strains, especially those carrying drug-resistant virulent plasmids, poses unprecedented threats/challenges to public health. This is a dangerous trend and should be closely monitored.


Assuntos
Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Plasmídeos/genética , beta-Lactamases/genética , Adulto , Animais , Antibacterianos/uso terapêutico , Genoma Bacteriano/genética , Humanos , Infecções por Klebsiella/tratamento farmacológico , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/patogenicidade , Masculino , Testes de Sensibilidade Microbiana , Mariposas/microbiologia , Virulência/genética , Fatores de Virulência/genética
5.
J Antimicrob Chemother ; 73(11): 3005-3015, 2018 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-30351436

RESUMO

Objectives: To provide detailed genetic characterization of four novel blaIMP-carrying transposons from Pseudomonas aeruginosa, Klebsiella pneumoniae and an Enterobacter sp. Methods: P. aeruginosa 60512, K. pneumoniae 447, P. aeruginosa 12939 and Enterobacter sp. A1137 were subjected to genome sequencing. The complete nucleotide sequences of two plasmids (p60512-IMP from the 60512 isolate and p447-IMP from the 447 isolate) and two chromosomes (the 12939 and A1137 isolates) were determined, then a genomic comparison of p60512-IMP, p447-IMP and four novel blaIMP-carrying transposons (Tn6394, Tn6375, Tn6411 and Tn6397) with related sequences was performed. Transferability of the blaIMP gene and bacterial antimicrobial susceptibility were tested. Results: Tn6394 and Tn6375 were located in p60512-IMP and p447-IMP, respectively, while Tn6411 and Tn6397 were integrated into the 12939 and A1137 chromosomes, respectively. Tn6394 was an ISPa17-based transposition unit that harboured the integron In992 (carrying blaIMP-1). In73 (carrying blaIMP-8), In73 and In992, together with the ISEcp1:IS1R-blaCTX-M-14-IS903D unit, the macAB-tolC region and the truncated aacC2-tmrB region, respectively, were integrated into the prototype transposons Tn1722, Tn1696 and Tn7, respectively, generating the Tn3-family unit transposons, Tn6375 and Tn6378, and the Tn7-family unit transposon Tn6411, respectively. Tn6397 was a large integrative and conjugative element carrying Tn6378. Conclusions: Complex events of transposition and homologous recombination have occurred during the original formation and further plasmid and chromosomal integration of these four transposons, promoting accumulation and spread of antimicrobial resistance genes.


Assuntos
Enterobacter/genética , Integrons/genética , Klebsiella pneumoniae/genética , Pseudomonas aeruginosa/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Cromossomos Bacterianos/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter/efeitos dos fármacos , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Plasmídeos/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Recombinação Genética , Sequenciamento Completo do Genoma
6.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(8): 917-21, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25223172

RESUMO

OBJECTIVE: To observe the effect of Kuntai Capsule (KC) on the number of retrieved oocytes, the quality of high-quality oocytes and embryos in in vitro fertilization of poor ovarian response (POR) patients. METHODS: Totally 70 POR patients preparing for in vitro fertilization-embryo transfer (IVF-ET) were randomly assigned to the observation group and the control group, 35 cases in each group. KC was administered to patients in the observation group in the preparation cycle (i.e., three menstrual cycles before IVF-ET) and during the superovulation process. Those in the control group took placebo during this period. Before and after medication the improvement of Shen yin deficiency syndrome (SYDS) was observed in the two groups. The basal follicle-stimulating hormone (bFSH), luteinizing hormone (LH), estradiol (E2), anti-Mullerian hormone (AMH), the ratio of FSH to LH, and antral follicle count (AFC) were observed. Besides, the E2 level of a single ovum on the day of HCG injection, the number of retrieved oocytes, the high-quality oocyte rate, and the high-quality embryos were observed. RESULTS: Compared with the control group, the SYDS, decreased bFSH and LH levels, increased ACF numbers, the E2 level of a single ovum on the day of HCG injection, the number of retrieved oocytes, high-quality oocytes, and high-quality embryos were superior in the observation group (P < 0.05). There was no statistical difference in the decreased FSH/LH level (P > 0.05). E2 and AMH increased after medication of KC in the observation group, while they decreased after administration of placebos in the control group. There was statistical difference in the post-pre treatment difference of E2 and AMH between the two groups (P < 0.05). CONCLUSION: KC could increase the number of retrieved oocytes, and elevate the quality of occytes and embryos in the IVF-ET.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Fertilização in vitro , Recuperação de Oócitos , Adulto , Transferência Embrionária , Feminino , Humanos , Oócitos/efeitos dos fármacos , Gravidez
7.
J Ethnopharmacol ; 329: 118092, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38604509

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Yu-Ping-Feng-San (YPF) is a traditional Chinese medicine formula that has therapeutic effects on allergic diseases such as allergic rhinitis and asthma. However, its potential efficacy and mechanism in the treatment of atopic dermatitis (AD) has not been extensively illustrated. AIM OF THE STUDY: The purpose of this study was to investigate the efficacy and possible mechanisms of YPF in AD pathogenesis. METHODS: Network pharmacology and GEO data mining were adopted to firstly identify the potential mechanisms of YPF on AD. Then DNCB induced-AD murine model was established to test the efficacy of YPF and verify its effects on inflammatory cytokines and NF-κB pathway. In addition, molecular docking was performed to detect the binding affinity of YPF's active components with NF-κB pathway related molecules. RESULTS: Network pharmacology and human data mining suggested that YPF may act on the NF-κB pathway in AD pathogenesis. With DNCB mice model, we found that YPF significantly improved AD symptoms, reduced SCORAD scores, and alleviated skin tissue inflammation in mice. At the same time, the expression of inflammatory cytokines, TNF-α, sPLA2-IIA and IL-6, was down-regulated. Moreover, YPF suppressed TLR4/MyD88/NF-κB pathway in situ in a dose-dependent manner. Molecular docking further confirmed that seven compounds in YPF had exceptional binding properties with TNF-α, IL-6 and TLR4. CONCLUSION: YPF may help the recovery of AD by inhibiting the TLR4/MyD88/NF-κB pathway, which provides novel insights for the treatment of AD by YPF.


Assuntos
Dermatite Atópica , Medicamentos de Ervas Chinesas , Simulação de Acoplamento Molecular , Fator 88 de Diferenciação Mieloide , NF-kappa B , Transdução de Sinais , Receptor 4 Toll-Like , Animais , Dermatite Atópica/tratamento farmacológico , Receptor 4 Toll-Like/metabolismo , NF-kappa B/metabolismo , Fator 88 de Diferenciação Mieloide/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Medicamentos de Ervas Chinesas/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos BALB C , Masculino , Modelos Animais de Doenças , Citocinas/metabolismo , Anti-Inflamatórios/farmacologia , Dinitroclorobenzeno , Farmacologia em Rede , Humanos , Inflamação/tratamento farmacológico , Feminino
8.
Front Public Health ; 11: 1043247, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36908448

RESUMO

Introduction: In the period of regular prevention and control of the COVID-19 pandemic, the public must continue to comply with the government's recommended preventive measures to further curb the pandemic. Based on the theories of protection motivation and cultural tightness-looseness, this study investigates individuals' compliance with the government's recommended preventive measures during this period in China. It also establishes a moderated mediation model to explore the underlying mechanisms. Methods: We used structural equation modeling and latent model structural equations to analyze data from an online survey of 443 participants. Results: The analysis showed that media exposure significantly predicted perceived severity, maladaptive rewards, self-efficacy, response efficacy, and response cost. Perceived severity, self-efficacy, and response efficacy were positively associated with protection motivation, which, in turn, was positively associated with individuals' compliance. Additionally, protection motivation positively affected individuals' compliance via implementation intention, and perceived cultural tightness-looseness significantly moderated the association between protection motivation and implementation intention. Discussion: This study helps to better understand individuals' compliance from a theoretical perspective and provide practical advice on promoting individuals' compliance with the government's precautionary measures.


Assuntos
COVID-19 , Humanos , Motivação , Pandemias/prevenção & controle , SARS-CoV-2 , China , Governo
9.
ACS Appl Mater Interfaces ; 15(30): 36468-36476, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37488666

RESUMO

The quality of the perovskite active layer directly impacts the photovoltaic performance of perovskite solar cells (PSCs). Unfortunately, perovskite films produced through solution methods often have a significant number of defects on their surface, which lead to a substantial degradation in the performance of devices. For this reason, a multifunctional additive 2-(trifluoromethyl) benzimidazole (TFMBI) is introduced into perovskite films. Based on the Lewis acid/base coordination principle, the TFMBI double site cooperatively passivates surface defects, inhibiting carrier non-radiative recombination. Simultaneously, the hydrophobic solid group (-CF3) of TFMBI covers the surface, establishing a moisture-oxygen barrier and improving the environmental stability of the devices. In consequence, the power conversion efficiency (PCE) of TFMBI-modified PSCs reached 23.16%, significantly higher than the pristine one with a PCE of 20.62%. Additionally, the unencapsulated target device retained 90.32% of its initial PCE even after being reserved in the air with a relative humidity of 20-30% for 60 days.

10.
Emerg Microbes Infect ; 12(2): 2275596, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37874004

RESUMO

Providencia as an opportunistic pathogen can cause serious infection, and moreover the emergence of multi-drug-resistant Providencia strains poses a potentially life-threatening risk to public health. However, a comprehensive genomic study to reveal the population structure and dissemination of Providencia is still lacking. In this study, we conducted a genomic epidemiology analysis on the 580 global sequenced Providencia isolates, including 257 ones sequenced in this study (42 ones were fully sequenced). We established a genome sequence-based species classification scheme for Providencia, redefining the conventional 11 Providencia species into seven genocomplexes that were further divided into 18 genospecies, providing an extensively updated reference for Providencia species discrimination based on the largest Providencia genome dataset to date. We then dissected the profile of antimicrobial resistance genes and the prevalence of multi-drug-resistant Providencia strains among these genocomplexes/genospecies, disclosing the presence of diverse and abundant antimicrobial resistance genes and high resistance ratios against multiple classes of drugs in Providencia. We further dissected the genetic basis for the spread of blaNDM-1 in Providencia. blaNDM-1 genes were mainly carried by five incompatible (Inc) groups of plasmids: IncC, IncW, IncpPROV114-NR, IncpCHS4.1-3, and IncpPrY2001, and the last three were newly designated in this study. By tracking the spread of blaNDM-1-carrying plasmids, IncC, IncpPROV114-NR, IncpCHS4.1-3, and IncpPrY2001 plasmids were found to be highly involved in parallel horizontal transfer or vertical clonal expansion of blaNDM-1 among Providencia. Overall, our study provided a comprehensive genomic view of species differentiation, antimicrobial resistance prevalence, and plasmid-mediated blaNDM-1 dissemination in Providencia.


Assuntos
Antibacterianos , Providencia , Providencia/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Plasmídeos/genética , beta-Lactamases/genética , Genômica , Testes de Sensibilidade Microbiana
11.
Front Microbiol ; 14: 1243371, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37808319

RESUMO

Introduction: Non-tuberculous mycobacteria (NTM) is a major category of environmental bacteria in nature that can be divided into rapidly growing mycobacteria (RGM) and slowly growing mycobacteria (SGM) based on their distinct growth rates. To explore differential molecular mechanisms between RGM and SGM is crucial to understand their survival state, environmental/host adaptation and pathogenicity. Comparative genomic analysis provides a powerful tool for deeply investigating differential molecular mechanisms between them. However, large-scale comparative genomic analysis between RGM and SGM is still uncovered. Methods: In this study, we screened 335 high-quality, non-redundant NTM genome sequences covering 187 species from 3,478 online NTM genomes, and then performed a comprehensive comparative genomic analysis to identify differential genomic characteristics and featured genes/protein domains between RGM and SGM. Results: Our findings reveal that RGM has a larger genome size, more genes, lower GC content, and more featured genes/protein domains in metabolism of some main substances (e.g. carbohydrates, amino acids, nucleotides, ions, and coenzymes), energy metabolism, signal transduction, replication, transcription, and translation processes, which are essential for its rapid growth requirements. On the other hand, SGM has a smaller genome size, fewer genes, higher GC content, and more featured genes/protein domains in lipid and secondary metabolite metabolisms and cellular defense mechanisms, which help enhance its genome stability and environmental adaptability. Additionally, orthogroup analysis revealed the important roles of bacterial division and bacteriophage associated genes in RGM and secretion system related genes for better environmental adaptation in SGM. Notably, PCoA analysis of the top 20 genes/protein domains showed precision classification between RGM and SGM, indicating the credibility of our screening/classification strategies. Discussion: Overall, our findings shed light on differential underlying molecular mechanisms in survival state, adaptation and pathogenicity between RGM and SGM, show the potential for our comparative genomic pipeline to investigate differential genes/protein domains at whole genomic level across different bacterial species on a large scale, and provide an important reference and improved understanding of NTM.

12.
Front Cell Infect Microbiol ; 13: 1240516, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37908762

RESUMO

Background: Tuberculosis (TB) remains a major global health concern, ranking as the second most lethal infectious disease following COVID-19. Smear-Negative Pulmonary Tuberculosis (SNPT) and Smear-Positive Pulmonary Tuberculosis (SPPT) are two common types of pulmonary tuberculosis characterized by distinct bacterial loads. To date, the precise molecular mechanisms underlying the differences between SNPT and SPPT patients remain unclear. In this study, we aimed to utilize proteomics analysis for identifying specific protein signatures in the plasma of SPPT and SNPT patients and further elucidate the molecular mechanisms contributing to different disease pathogenesis. Methods: Plasma samples from 27 SPPT, 37 SNPT patients and 36 controls were collected and subjected to TMT-labeled quantitative proteomic analyses and targeted GC-MS-based lipidomic analysis. Ingenuity Pathway Analysis (IPA) was then performed to uncover enriched pathways and functionals of differentially expressed proteins. Results: Proteomic analysis uncovered differential protein expression profiles among the SPPT, SNPT, and Ctrl groups, demonstrating dysfunctional immune response and metabolism in both SPPT and SNPT patients. Both groups exhibited activated innate immune responses and inhibited fatty acid metabolism, but SPPT patients displayed stronger innate immune activation and lipid metabolic inhibition compared to SNPT patients. Notably, our analysis uncovered activated antigen-presenting cells (APCs) in SNPT patients but inhibited APCs in SPPT patients, suggesting their critical role in determining different bacterial loads/phenotypes in SNPT and SPPT. Furthermore, some specific proteins were detected to be involved in the APC activation/acquired immune response, providing some promising therapeutic targets for TB. Conclusion: Our study provides valuable insights into the differential molecular mechanisms underlying SNPT and SPPT, reveals the critical role of antigen-presenting cell activation in SNPT for effectively clearing the majority of Mtb in bodies, and shows the possibility of APC activation as a novel TB treatment strategy.


Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Tuberculose , Humanos , Metabolismo dos Lipídeos , Proteômica , Tuberculose Pulmonar/microbiologia , Imunidade Adaptativa , Escarro/microbiologia
13.
Environ Sci Technol ; 46(4): 2337-44, 2012 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-22260249

RESUMO

A combined adsorption-discharge plasma catalytic process was used for the removal of NO(x) using zeolites as catalysts without external heating. It was found that the types of plasma carrier gases exert great effect on the conversion of adsorbed NO(x). The conversion of adsorbed NO(x) is much lower in N(2) plasma than in Ar plasma, which is attributed to the reverse reaction, NO(x) formation reaction. The momentary increase of oxygen species derived from the decomposition of adsorbed NO(x) is considered to be the main cause as their collisions with nitrogen species can generate NO(x) again. Thus, solid carbon was added to the catalyst to act as a scavenger for active oxygen species to improve the conversion of adsorbed NO(x) in N(2) plasma. A NO(x) removal rate of 97.8% was obtained on 8.5wt.% carbon mixed H-ZSM-5 at an energy efficiency of 0.758 mmol NO(x)/W·h.


Assuntos
Poluentes Atmosféricos/química , Poluição do Ar/prevenção & controle , Óxidos de Nitrogênio/química , Adsorção , Silicatos de Alumínio/química , Carbono/química , Catálise , Ferro/química , Manganês/química , Óxidos/química , Zircônio/química
14.
Genomics Proteomics Bioinformatics ; 20(6): 1154-1167, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35307590

RESUMO

The rapid spread of carbapenemase-producing Klebsiella pneumoniae (cpKP) poses serious threats to public health; however, the underlying genetic basis for its dissemination is still unknown. We conducted a comprehensive genomic epidemiology analysis on 420 cpKP isolates collected from 70 hospitals in 24 provinces/autonomous regions/municipalities of China during 2009-2017 by short-/long-read sequencing. The results showed that most cpKP isolates were categorized into clonal group 258 (CG258), in which ST11 was the dominant clone. Phylogenetic analysis revealed three major clades including the top one of Clade 3 for CG258 cpKP isolates. Additionally, carbapenemase gene analysis indicated that blaKPC was dominant in the cpKP isolates, and most blaKPC genes were located in five major incompatibility (Inc) groups of blaKPC-harboring plasmids. Importantly, three advantageous combinations of host-blaKPC-carrying plasmid (Clade 3.1+3.2-IncFIIpHN7A8, Clade 3.1+3.2-IncFIIpHN7A8:IncR, and Clade 3.3-IncFIIpHN7A8:IncpA1763-KPC) were identified to confer cpKP isolates the advantages in both genotypes (strong correlation/coevolution) and phenotypes (resistance/growth/competition) to facilitate the nationwide spread of ST11/CG258 cpKP. Intriguingly, Bayesian skyline analysis illustrated that the three advantageous combinations might be directly associated with the strong population expansion during 2007-2008 and subsequent maintenance of the population of ST11/CG258 cpKP after 2008. We then examined drug resistance profiles of these cpKP isolates and proposed combination treatment regimens for CG258/non-CG258 cpKP infections. Thus, the findings of our systematical analysis shed light on the molecular epidemiology and genetic basis for the dissemination of ST11/CG258 cpKP in China, and much emphasis should be given to the close monitoring of advantageous cpKP-plasmid combinations.


Assuntos
Proteínas de Bactérias , Klebsiella pneumoniae , Klebsiella pneumoniae/genética , Filogenia , Teorema de Bayes , Proteínas de Bactérias/genética , Genômica , China/epidemiologia , Plasmídeos/genética , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico
15.
Front Cell Infect Microbiol ; 12: 973901, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36093205

RESUMO

As a newly emerging Klebsiella pathogen, more and more Klebsiella michiganensis drug resistant strains have been reported in recent years, which posed serious threats to public health. Here we first reported a multidrug-resistant K. michiganensis strain 12084 with two bla SIM-1 and one mcr-9.2 genes isolated from the sputum specimen of a patient in the Second Affiliated Hospital of Zhejiang University School of Medicine and analyzed its genetic basis and drug-resistance phenotypes. Genetic analysis showed that this strain harbored three different incompatibility groups (IncHI2, IncHI5, and IncFIIpKPHS2:IncFIB-4.1) of plasmids (p12084-HI2, p12084-HI5, and p12084-FII). A total of 26 drug-resistance genes belonging to 12 classes of antibiotics were identified, most of which (24) were located on two plasmids (p12084-HI2 and p12084-HI5). Interestingly, two bla SIM-1 genes were identified to locate on p12084-HI2 and p12084-HI5, respectively, both of which were embedded in In630, indicating their genetic homogeny. It was noting that one bla SIM-1 gene was situated in a novel unit transposon (referred to as Tn6733) on the p12084-HI5 plasmid. We also discovered an mcr-9.2 gene on the p12084-HI2 plasmid. To the best of our knowledge, this is the first report of a bla SIM-1 and mcr-9.2 harboring K. michiganensis strain. We then investigated the population structure/classification, and antibiotic resistance for all 275 availably global K. michiganensis genomes. Population structure revealed that K. michiganensis could be divided into two main clades (Clade 1 and Clade 2); the most popular ST29 was located in Clade 1, while other common STs (such as ST50, ST27, and ST43) were located in Clade 2. Drug-resistance analysis showed 25.5% of the K. michiganensis strains (70/275) harboring at least one carbapenemase gene, indicating severe drug resistance of K. michiganensis beyond our imagination; this is a dangerous trend and should be closely monitored, especially for ST27 K. michiganensis with the most drug-resistant genes among all the STs. Overall, we reported a bla SIM-1 and mcr-9.2 harboring K. michiganensis strain, and further revealed the population structure/classification, and drug-resistance of K. michiganensis, which provided an important framework, reference, and improved understanding of K. michiganensis.


Assuntos
Colistina , Farmacorresistência Bacteriana Múltipla , Farmacorresistência Bacteriana Múltipla/genética , Genômica , Humanos , Klebsiella/genética
16.
Genomics Proteomics Bioinformatics ; 20(2): 418-434, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-34214662

RESUMO

Klebsiella pneumoniae (K. pneumoniae) is an important pathogen that can cause severe hospital- and community-acquired infections. To systematically investigate its methylation features, we determined the whole-genome sequences of 14 K. pneumoniae strains covering varying serotypes, multilocus sequence types, clonal groups, viscosity/virulence, and drug resistance. Their methylomes were further characterized using Pacific Biosciences single-molecule real-time and bisulfite technologies. We identified 15 methylation motifs [13 N6-methyladenine (6mA) and two 5-methylcytosine (5mC) motifs], among which eight were novel. Their corresponding DNA methyltransferases were also validated. Additionally, we analyzed the genomic distribution of GATC and CCWGG methylation motifs shared by all strains, and identified differential distribution patterns of some hemi-/un-methylated GATC motifs, which tend to be located within intergenic regions (IGRs). Specifically, we characterized the in vivo methylation kinetics at single-base resolution on a genome-wide scale by simulating the dynamic processes of replication-mediated passive demethylation and MTase-catalyzed re-methylation. The slow methylation of the GATC motifs in the replication origin (oriC) regions and IGRs implicates the epigenetic regulation of replication initiation and transcription. Our findings illustrate the first comprehensive dynamic methylome map of K. pneumoniae at single-base resolution, and provide a useful reference to better understand epigenetic regulation in this and other bacterial species.


Assuntos
Epigênese Genética , Epigenoma , Klebsiella pneumoniae/genética , Cinética , Metilação de DNA
17.
mLife ; 1(4): 460-464, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38818485

RESUMO

We have developed a manually curated online reference database, DANMEL (http://124.239.252.254/danmel/), that addresses the lack of accurate dissection and annotation of the genetic structures of mobile genetic elements (MGEs) with genes for drug resistance. DANMEL contains accurately annotated and genetically dissected reference MGEs covering 5 categories and 135 subcategories/subfamilies of MGEs. Further, DANMEL provides a detailed guide on how to precisely annotate MGEs. DANMEL also provides SEARCH/BLAST functions to facilitate finding reference MGEs. Overall, DANMEL will aid researchers to conduct in-depth genetic analysis of sequenced bacterial MGEs with drug-resistance genes and further facilitate a better understanding of bacterial MGEs associated with drug resistance at a genomic level.

18.
Front Cell Infect Microbiol ; 11: 690799, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34211858

RESUMO

In this study, a detailed genetic dissection of the huge and complex blaNDM-carrying genetic elements and their related mobile genetic elements was performed in Enterobacteriaceae. An extensive comparison was applied to 12 chromosomal genetic elements, including six sequenced in this study and the other six from GenBank. These 12 genetic elements were divided into five groups: a novel IME Tn6588; two related IMEs Tn6523 (SGI1) and Tn6589; four related ICEs Tn6512 (R391), Tn6575 (ICEPvuChnBC22), Tn6576, and Tn6577; Tn7 and its derivatives Tn6726 and 40.7-kb Tn7-related element; and two related IMEs Tn6591 (GIsul2) and Tn6590. At least 51 resistance genes, involved in resistance to 18 different categories of antibiotics and heavy metals, were found in these 12 genetic elements. Notably, Tn6576 carried another ICE Tn6582. In particular, the six blaNDM-carrying genetic elements Tn6588, Tn6589, Tn6575, Tn6576, Tn6726, and 40.7-kb Tn7-related element contained large accessory multidrug resistance (MDR) regions, each of which had a very complex mosaic structure that comprised intact or residual mobile genetic elements including insertion sequences, unit or composite transposons, integrons, and putative resistance units. Core blaNDM genetic environments manifested as four different Tn125 derivatives and, notably, two or more copies of relevant Tn125 derivatives were found in each of Tn6576, Tn6588, Tn6589, and 40.7-kb Tn7-related element. The huge and complex blaNDM-carrying genetic elements were assembled from complex transposition and homolog recombination. Firstly identified were eight novel mobile elements, including three ICEs Tn6576, Tn6577, and Tn6582, two IMEs, Tn6588 and Tn6589, two composite transposons Tn6580a and Tn6580b, and one integron In1718.


Assuntos
Infecções por Enterobacteriaceae , Enterobacteriaceae , Antibacterianos/farmacologia , Elementos de DNA Transponíveis , Enterobacteriaceae/genética , Humanos , Integrons/genética , Plasmídeos/genética , beta-Lactamases/genética
19.
Oncol Lett ; 17(5): 4742, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30944660

RESUMO

[This retracts the article DOI: 10.3892/ol.2016.4607.].

20.
J Glob Antimicrob Resist ; 19: 358-364, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31216492

RESUMO

OBJECTIVES: The aim of this study was to perform a detailed genomic characterisation of IncR plasmids from China. METHODS: Three IncR plasmids (p13190-tetA, p02085-tetA and p30860-tetA) from clinical isolates ofKlebsiella pneumoniae, Citrobacter freundii and Enterobacter cloacae, respectively, were fully sequenced using high-throughput genome sequencing and were compared with five previously sequenced IncR plasmids (pHN84KPC, pSH-01, pK245, pKPC_P16 and pKPC-LK30) from China. RESULTS: The eight IncR plasmids from China possessed conserved IncR backbones composed of repB, parAB, umuCD, retA and resD. Resistance accessory modules integrated into the IncR backbones included multidrug resistance (MDR) regions in p30860-tetA, p02085-tetA, p13190-tetA and pK245, blaKPC-2 regions in pHN84KPC, pKPC-LK30 and pKPC_P16, and the ΔTn1721-sil region in pSH-01. These resistance accessory modules were inserted at a site between retA and vagD, resulting in loss of the backbone genes vagCD in some of the plasmids. The resistance accessory modules differed dramatically from one another and carried distinct profiles of resistance markers. In particular, all of p13190-tetA, p02085-tetA, p30860-tetA, pHN84KPC, pSH-01 and pK245 carried tetracycline resistance tet gene modules, and the carbapenemase gene blaKPC-2 was identified in pHN84KPC, pKPC-LK30 and pKPC_P16. In addition, one or more regions responsible for plasmid replication and/or maintenance were found in some of the resistance accessory modules, facilitating stable replication of corresponding IncR plasmids at steady-state copy numbers. CONCLUSIONS: This detailed comparative genomics analysis of IncR plasmids from China provides a deeper insight into the diversification and evolution of IncR plasmids.


Assuntos
Citrobacter freundii/genética , Enterobacter cloacae/genética , Variação Genética , Genoma Bacteriano , Klebsiella pneumoniae/genética , Plasmídeos/genética , Idoso , Bacteriemia/microbiologia , Sistema Biliar/microbiologia , China , Genômica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Escarro/microbiologia
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