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1.
Int J Mol Sci ; 22(12)2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-34200743

RESUMO

Mastitis is a common disease in dairy cows that is mostly caused by E. coli, and it brings massive losses to the dairy industry. N6-Methyladenosine (m6A), a methylation at the N6 position of RNA adenine, is a type of modification strongly associated with many diseases. However, the role of m6A in mastitis has not been investigated. In this study, we used MeRIP-seq to sequence the RNA of bovine mammary epithelial cells treated with inactivated E. coli for 24 h. In this in vitro infection model, there were 16,691 m6A peaks within 7066 mRNA transcripts in the Con group and 10,029 peaks within 4891 transcripts in the E. coli group. Compared with the Con group, 474 mRNAs were hypermethylated and 2101 mRNAs were hypomethylated in the E. coli group. Biological function analyses revealed differential m6A-modified genes mainly enriched in the MAPK, NF-κB, and TGF-ß signaling pathways. In order to explore the relationship between m6A and mRNA expression, combined MeRIP-seq and mRNA-seq analyses revealed 212 genes with concomitant changes in the mRNA expression and m6A modification. This study is the first to present a map of RNA m6A modification in mastitis treated with E. coli, providing a basis for future research.


Assuntos
Adenosina/análogos & derivados , Metilação de DNA , Células Epiteliais/metabolismo , Infecções por Escherichia coli/veterinária , Regulação da Expressão Gênica , Glândulas Mamárias Animais/metabolismo , Mastite Bovina/genética , Adenosina/química , Animais , Bovinos , Células Epiteliais/imunologia , Células Epiteliais/microbiologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/imunologia , Feminino , Perfilação da Expressão Gênica , Glândulas Mamárias Animais/imunologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/imunologia , Mastite Bovina/microbiologia
2.
Int J Mol Sci ; 22(11)2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34199768

RESUMO

Single mutations can confer resistance to antibiotics. Identifying such mutations can help to develop and improve drugs. Here, we systematically screen for candidate quinolone resistance-conferring mutations. We sequenced highly diverse wastewater E. coli and performed a genome-wide association study (GWAS) to determine associations between over 200,000 mutations and quinolone resistance phenotypes. We uncovered 13 statistically significant mutations including 1 located at the active site of the biofilm dispersal gene bdcA and 6 silent mutations in the aminoacyl-tRNA synthetase valS. The study also recovered the known mutations in the topoisomerases gyrase (gyrA) and topoisomerase IV (parC). In summary, we demonstrate that GWAS effectively and comprehensively identifies resistance mutations without a priori knowledge of targets and mode of action. The results suggest that mutations in the bdcA and valS genes, which are involved in biofilm dispersal and translation, may lead to novel resistance mechanisms.


Assuntos
Farmacorresistência Bacteriana/genética , Proteínas de Escherichia coli/genética , Escherichia coli/genética , Mutação/genética , Quinolonas/farmacologia , Águas Residuárias/microbiologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Loci Gênicos , Estudo de Associação Genômica Ampla , Desequilíbrio de Ligação/genética , Modelos Moleculares , Fenótipo , Filogenia
3.
BMC Infect Dis ; 21(1): 683, 2021 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-34261450

RESUMO

BACKGROUND: Third-generation cephalosporin-resistant Gram-negatives (3GCR-GN) and vancomycin-resistant enterococci (VRE) are common causes of multi-drug resistant healthcare-associated infections, for which gut colonisation is considered a prerequisite. However, there remains a key knowledge gap about colonisation and infection dynamics in high-risk settings such as the intensive care unit (ICU), thus hampering infection prevention efforts. METHODS: We performed a three-month prospective genomic survey of infecting and gut-colonising 3GCR-GN and VRE among patients admitted to an Australian ICU. Bacteria were isolated from rectal swabs (n = 287 and n = 103 patients ≤2 and > 2 days from admission, respectively) and diagnostic clinical specimens between Dec 2013 and March 2014. Isolates were subjected to Illumina whole-genome sequencing (n = 127 3GCR-GN, n = 41 VRE). Multi-locus sequence types (STs) and antimicrobial resistance determinants were identified from de novo assemblies. Twenty-three isolates were selected for sequencing on the Oxford Nanopore MinION device to generate completed reference genomes (one for each ST isolated from ≥2 patients). Single nucleotide variants (SNVs) were identified by read mapping and variant calling against these references. RESULTS: Among 287 patients screened on admission, 17.4 and 8.4% were colonised by 3GCR-GN and VRE, respectively. Escherichia coli was the most common species (n = 36 episodes, 58.1%) and the most common cause of 3GCR-GN infection. Only two VRE infections were identified. The rate of infection among patients colonised with E. coli was low, but higher than those who were not colonised on admission (n = 2/33, 6% vs n = 4/254, 2%, respectively, p = 0.3). While few patients were colonised with 3GCR- Klebsiella pneumoniae or Pseudomonas aeruginosa on admission (n = 4), all such patients developed infections with the colonising strain. Genomic analyses revealed 10 putative nosocomial transmission clusters (≤20 SNVs for 3GCR-GN, ≤3 SNVs for VRE): four VRE, six 3GCR-GN, with epidemiologically linked clusters accounting for 21 and 6% of episodes, respectively (OR 4.3, p = 0.02). CONCLUSIONS: 3GCR-E. coli and VRE were the most common gut colonisers. E. coli was the most common cause of 3GCR-GN infection, but other 3GCR-GN species showed greater risk for infection in colonised patients. Larger studies are warranted to elucidate the relative risks of different colonisers and guide the use of screening in ICU infection control.


Assuntos
Infecção Hospitalar , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli , Trato Gastrointestinal/microbiologia , Controle de Infecções , Unidades de Terapia Intensiva , Enterococos Resistentes à Vancomicina , Antibacterianos/farmacologia , Austrália/epidemiologia , Resistência às Cefalosporinas/genética , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Escherichia coli/patogenicidade , Humanos , Controle de Infecções/métodos , Controle de Infecções/normas , Unidades de Terapia Intensiva/normas , Unidades de Terapia Intensiva/estatística & dados numéricos , Estudos Prospectivos , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação
4.
BMC Infect Dis ; 21(1): 578, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-34130629

RESUMO

BACKGROUND: Antibiotic Resistance is an imminent global public health threat. Antibiotic resistance emerged in healthcare settings and has now moved on to the community settings. This study was conducted to identify the rates of asymptomatic colonization with selected antibiotic resistant organisms, (Methicillin Resistant Staphylococcus aureus (MRSA), Extended Spectrum Beta Lactamase (ESBL) producing Escherichia coli and Klebsiella spp and carbapenem resistant E.coli and Klebsiella spp) - among a group of university students in Sri Lanka. Identification of genetic determinants of MRSA and ESBL was an additional objective of the study. METHODS: A self - collected nasal swab and a peri-rectal swab collected after passing stools were obtained. Routine microbiological methods were used for the isolation S.aureus from the nasal swab and E.coli and Klebsiella species from the peri-rectal swab. Antibiotic sensitivity testing was performed as recommended by clinical and laboratory standard institute (CLSI). Three (3) genes that are responsible for ESBL production; blaCTX-M, blaSHV, and blaTEM were tested using previously described primers and PCR procedures. Identification of MecA and PVL genes attributed to MRSA was also done with PCR. RESULTS: A total of 322 participants between 21 and 28 years were recruited representing 5 different faculties of study. Seventy one (22.0%) were colonized with S.aureus and 14 among them with MRSA, making the MRSA colonization rate of 4.3%. Forty five (15%) of the participants were colonized with an ESBL producing E.coli or Klebsiella spp. No one was colonized with carbapenem resistant E.coli or Klebsiella species. Of the 45 ESBL producers the commonest genetic determinant identified was blaCTX-M (n = 36), while 16 isolates had blaTEM and 7 had blaSHV. Similarly, of the 14 isolates identified as MRSA, 3 (21.4%) were found to be PVL positive while 11 (78.6%) were MecA positive. CONCLUSIONS: A high rate of colonization with ESBL producing E.coli and Klebsiella species was noted in our study group.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Farmacorresistência Bacteriana , Universidades , Adulto , Bactérias/efeitos dos fármacos , Infecções Bacterianas/tratamento farmacológico , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Carbapenêmicos/uso terapêutico , Estudos de Coortes , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Klebsiella/isolamento & purificação , Infecções por Klebsiella/microbiologia , Masculino , Staphylococcus aureus Resistente à Meticilina/genética , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Testes de Sensibilidade Microbiana , Sri Lanka , Infecções Estafilocócicas/microbiologia , Estudantes , Adulto Jovem , beta-Lactamases/genética
5.
J Vet Diagn Invest ; 33(4): 744-748, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34159856

RESUMO

We analyzed the correlation between minimum inhibitory concentrations (MICs) of antimicrobials used in humans and those used in animals to enable comparison of antimicrobial susceptibility between Escherichia coli isolated from humans and those from animals. We compared the following pairs of MIC data: piperacillin (PIPC) to ampicillin (ABPC), amikacin (AMK) to kanamycin (KM), minocycline (MINO) to oxytetracycline (OTC), and levofloxacin (LVFX) to enrofloxacin (ERFX) using 103 isolates of E. coli from healthy livestock (cattle, pigs, broiler chickens, and layer chickens). Kappa analysis of the agreement for resistance and susceptibility between PIPC and ABPC, AMK and KM, MINO and OTC, and LVFX and ERFX showed almost perfect (κ = 0.81), slight (κ = 0.12), fair (κ = 0.37), and moderate (κ = 0.46) agreement, respectively. Within the antimicrobial pairs, all isolates resistant to the human antimicrobial were also resistant to the veterinary antimicrobial. However, there was less agreement within the pairs for those isolates that were sensitive to the human antimicrobial. The percentage agreement for susceptibility, defined as the percentage of isolates sensitive to both antimicrobials compared with isolates sensitive to both antimicrobials, as well as those sensitive only to the human antimicrobial, was 89.9%, 87.3%, 64.0%, and 89.9% for PIPC and ABPC, AMK and KM, MINO and OTC, and LVFX and ERFX, respectively. Our results suggest that the possibility of missing the resistance for antimicrobials used in human medicine by examining MICs for the equivalent antimicrobials used in veterinary medicine is low.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Gado/microbiologia , Animais , Escherichia coli/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana
6.
BMC Infect Dis ; 21(1): 600, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162341

RESUMO

BACKGROUND: This antimicrobial surveillance study reports in vitro antimicrobial activity and susceptibility data for a panel of agents against respiratory isolates of Enterobacterales and Pseudomonas aeruginosa. METHODS: Isolates from respiratory specimens were collected in Africa/Middle East, Asia/South Pacific, Europe and Latin America between 2016 and 2018, as part of the Antimicrobial Testing Leadership and Surveillance (ATLAS) program. Broth microdilution methodology was used to quantify minimum inhibitory concentrations, from which rates of susceptibility were determined using EUCAST breakpoints (version 10). Rates of subsets with genes encoding ß-lactamases (extended-spectrum ß-lactamases [ESBLs], serine carbapenemases and metallo-ß-lactamases [MBLs]) were also determined, as well as rates of multidrug-resistant (MDR) P. aeruginosa. RESULTS: Among all respiratory Enterobacterales isolates, susceptibility to ceftazidime-avibactam, meropenem, colistin and amikacin was ≥94.4% in each region. For Enterobacterales isolates that were ESBL-positive or carbapenemase-positive/MBL-negative, ceftazidime-avibactam susceptibility was 93.6 and 98.9%, respectively. Fewer than 42.7% of MBL-positive Enterobacterales isolates were susceptible to any agents, except colistin (89.0% susceptible). Tigecycline susceptibility was ≥90.0% among Citrobacter koseri and Escherichia coli isolates, including all ß-lactamase-positive subsets. ESBL-positive Enterobacterales were more commonly identified in each region than isolates that were ESBL/carbapenemase-positive; carbapenemase-positive/MBL-negative; or MBL-positive. Among all respiratory P. aeruginosa isolates, the combined susceptibility rates (susceptible at standard dosing regimen plus susceptible at increased exposure) were highest to ceftazidime-avibactam, colistin and amikacin (≥82.4% in each region). Susceptibility to colistin was ≥98.1% for all ß-lactamase-positive subsets of P. aeruginosa. The lowest rates of antimicrobial susceptibility were observed among MBL-positive isolates of P. aeruginosa (≤56.6%), with the exception of colistin (100% susceptible). MDR P. aeruginosa were most frequently identified in each region (18.7-28.7%), compared with the subsets of ESBL-positive; carbapenemase-positive/MBL-negative; or MBL-positive isolates. CONCLUSIONS: Rates of susceptibility among the collections of respiratory Enterobacterales and P. aeruginosa isolates were highest to ceftazidime-avibactam, colistin and amikacin in each region. Tigecycline was active against all subsets of C. koseri and E. coli, and colistin was active against all subsets of P. aeruginosa. The findings of this study indicate the need for continued antimicrobial surveillance among respiratory Gram-negative pathogens, in particular those with genes encoding MBLs.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Amicacina/farmacologia , Compostos Azabicíclicos/farmacologia , Proteínas de Bactérias/genética , Ceftazidima/farmacologia , Citrobacter koseri/efeitos dos fármacos , Citrobacter koseri/isolamento & purificação , Colistina/farmacologia , Combinação de Medicamentos , Monitoramento Epidemiológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Humanos , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , Tigeciclina/farmacologia , beta-Lactamases/genética
7.
Ann Agric Environ Med ; 28(2): 271-276, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34184510

RESUMO

INTRODUCTION: The article discusses the antimicrobial resistance of poultry-isolated bacteria in the Wielkopolska region of Poland. MATERIAL AND METHODS: From August 2014 - June 2016, antibiotic resistance screening tests were performed involving 4,496 samples of Escherichia coli and 84 samples of Klebsiella spp., and the following antibiotics: amoxicillin, amoxicillin with clavulanic acid, colistin, doxycycline, enrofloxacin, florfenicol, neomycin, norfloxacin, spectinomycin, and trimethoprim with sulfamethoxazole. The research used broth the microdilution method and CLSI standards. RESULTS: During the investigation period of 22 months a growing percentage of E. coli isolates showed antibiotic resistance to amoxicillin, amoxicillin with clavulanic acid, colistin, enrofloxacin, neomycin, norfloxacin, spectinomycin, and trimethoprim with sulfamethoxazole. Resistance to doxycycline and florfenicol decreased. The most efficient antibiotics against E. coli were colistin (84.64 %), neomycin (80.62 %), and amoxicillin with clavulanic acid (73.05 %). Klebsiella samples were the most susceptible to neomycin (85.71 %), colistin (84.52 %), and trimethoprim with sulfamethoxazole (73.81 %). CONCLUSIONS: Antibiotic resistance of pathogenic micro-organisms, such as Escherichia coli and Klebsiella spp., is a serious problem both for poultry producers and for public health protection. Low efficiency of numerous antibiotic groups forces reflection on limiting the use of medicines in food-producing animals.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/veterinária , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Klebsiella/efeitos dos fármacos , Doenças das Aves Domésticas/microbiologia , Animais , Galinhas/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Klebsiella/genética , Klebsiella/isolamento & purificação , Testes de Sensibilidade Microbiana , Polônia
8.
Biosensors (Basel) ; 11(5)2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34067116

RESUMO

A regenerable bulk acoustic wave (BAW) biosensor is developed for the rapid, label-free and selective detection of Escherichia coli in liquid media. The geometry of the biosensor consists of a GaAs membrane coated with a thin film of piezoelectric ZnO on its top surface. A pair of electrodes deposited on the ZnO film allows the generation of BAWs by lateral field excitation. The back surface of the membrane is functionalized with alkanethiol self-assembled monolayers and antibodies against E. coli. The antibody immobilization was investigated as a function of the concentration of antibody suspensions, their pH and incubation time, designed to optimize the immunocapture of bacteria. The performance of the biosensor was evaluated by detection tests in different environments for bacterial suspensions ranging between 103 and 108 CFU/mL. A linear dependence between the frequency response and the logarithm of E. coli concentration was observed for suspensions ranging between 103 and 107 CFU/mL, with the limit of detection of the biosensor estimated at 103 CFU/mL. The 5-fold regeneration and excellent selectivity towards E. coli detected at 104 CFU/mL in a suspension tinted with Bacillus subtilis at 106 CFU/mL illustrate the biosensor potential for the attractive operation in complex biological media.


Assuntos
Técnicas Biossensoriais , Escherichia coli/isolamento & purificação , Som , Anticorpos , Arsenicais , Eletrodos , Gálio , Ouro , Limite de Detecção , Regeneração , Óxido de Zinco
9.
Res Vet Sci ; 137: 174-185, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34000648

RESUMO

The antimicrobial resistance (AMR) in human and animal pathogens is a global concern, and antimicrobial use (AMU) is considered the most important driver for its increase. The aim of this study was to assess AMR in Escherichia coli and Enterococcus spp. in faecal samples of pigs subjected to four different AMU protocols from birth to finishing: G1, no in-feed antimicrobials; G2: a total average dose 6018 mg antimicrobials/pig; G3: a total average dose 8127 mg antimicrobials/pig; and G4: a total average dose 15,678 mg antimicrobials/pig. Faecal samples were collected at six time points and AMR was assessed in both bacteria. The microbiota composition was assessed by 16S rRNA sequencing. Minor differences on the microbiota profile was observed among groups, but a lower Firmicutes:Bacteroidetes ratio was noted in G4. Escherichia coli and Enterococcus spp. strains isolated from all groups showed a high level of multi-drug resistance (MDR). The amount of antimicrobials used was significantly positively associated with the probability of MDR in both bacteria. Approximately 43% of the variation in MIC90 for colistin could be explained by AMU, and a one-day increase in administration of colistin increased MIC90 by 0.05 µg mL-1. In conclusion, the results suggest that the higher the use of antimicrobials in farms, the higher the MDR frequency and resistance to the highest priority critically important antimicrobials for humans in commensal gut bacteria of pigs.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Doenças dos Suínos/microbiologia , Animais , Antibacterianos/administração & dosagem , Revisão de Uso de Medicamentos , Enterococcus/genética , Enterococcus/isolamento & purificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/veterinária , Fezes/microbiologia , RNA Ribossômico 16S , Suínos
10.
Int J Mol Sci ; 22(9)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946710

RESUMO

Considering the advent of antibiotic resistance, the study of bacterial metabolic behavior stimulated by novel antimicrobial agents becomes a relevant tool to elucidate involved adaptive pathways. Profiling of volatile metabolites was performed to monitor alterations of bacterial metabolism induced by biosynthesized silver nanoparticles (bio-AgNPs). Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae and Proteus mirabilis were isolated from pressure ulcers, and their cultures were prepared in the presence/absence of bio-AgNPs at 12.5, 25 and 50 µg mL-1. Headspace solid phase microextraction associated to gas chromatography-mass spectrometry was the employed analytical platform. At the lower concentration level, the agent promoted positive modulation of products of fermentation routes and bioactive volatiles, indicating an attempt of bacteria to adapt to an ongoing suppression of cellular respiration. Augmented response of aldehydes and other possible products of lipid oxidative cleavage was noticed for increasing levels of bio-AgNPs. The greatest concentration of agent caused a reduction of 44 to 80% in the variety of compounds found in the control samples. Pathway analysis indicated overall inhibition of amino acids and fatty acids routes. The present assessment may provide a deeper understanding of molecular mechanisms of bio-AgNPs and how the metabolic response of bacteria is untangled.


Assuntos
Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Nanopartículas Metálicas/uso terapêutico , Lesão por Pressão/tratamento farmacológico , Lesão por Pressão/microbiologia , Prata/uso terapêutico , Compostos Orgânicos Voláteis/metabolismo , Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/metabolismo , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Escherichia coli/metabolismo , Humanos , Técnicas In Vitro , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/metabolismo , Redes e Vias Metabólicas/efeitos dos fármacos , Metaboloma/efeitos dos fármacos , Metabolômica , Testes de Sensibilidade Microbiana , Proteus mirabilis/efeitos dos fármacos , Proteus mirabilis/isolamento & purificação , Proteus mirabilis/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/classificação
11.
ACS Appl Mater Interfaces ; 13(16): 19230-19243, 2021 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-33852268

RESUMO

The selective isolation of bacteria from mixed populations has been investigated in varied applications ranging from differential pathogen identification in medical diagnostics and food safety to the monitoring of microbial stress dynamics in industrial bioreactors. Selective isolation techniques are generally limited to the confinement of small populations in defined locations, may be unable to target specific bacteria, or rely on immunomagnetic separation, which is not universally applicable. In this proof-of-concept work, we describe a novel strategy combining inducible bacterial lectin expression with magnetic glyconanoparticles (MGNPs) as a platform technology to enable selective bacterial isolation from cocultures. An inducible mutant of the type 1 fimbriae, displaying the mannose-specific lectin FimH, was constructed in Escherichia coli allowing for "on-demand" glycan-binding protein presentation following external chemical stimulation. Binding to glycopolymers was only observed upon fimbrial induction and was specific for mannosylated materials. A library of MGNPs was produced via the grafting of well-defined catechol-terminal glycopolymers prepared by reversible addition-fragmentation chain transfer (RAFT) polymerization to magnetic nanoparticles. Thermal analysis revealed high functionalization (≥85% polymer by weight). Delivery of MGNPs to cocultures of fluorescently labeled bacteria followed by magnetic extraction resulted in efficient depletion of type 1 fimbriated target cells from wild-type or afimbriate E. coli. Extraction efficiency was found to be dependent on the molecular weight of the glycopolymers utilized to engineer the nanoparticles, with MGNPs decorated with shorter Dopa-(ManAA)50 mannosylated glycopolymers found to perform better than those assembled from a longer Dopa-(ManAA)200 analogue. The extraction efficiency of fimbriated E. coli was also improved when the counterpart strain did not harbor the genetic apparatus for the expression of the type 1 fimbriae. Overall, this work suggests that the modulation of the genetic apparatus encoding bacterial surface-associated lectins coupled with capture through MGNPs could be a versatile tool for the extraction of bacteria from mixed populations.


Assuntos
Escherichia coli/genética , Escherichia coli/isolamento & purificação , Glicoproteínas/química , Lectinas/genética , Imãs/química , Nanopartículas/química , Aderência Bacteriana , Expressão Gênica , Glicoproteínas/metabolismo , Polímeros/química
12.
Int J Food Microbiol ; 347: 109196, 2021 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-33906045

RESUMO

Due to the recent outbreaks of Salmonella and Escherichia coli in fresh produce in the United States, the transfer of foodborne pathogens between animal feeding operations and fresh produce continues to be a considerable risk. The purpose of this study was to determine if the establishment of a vegetation barrier (VB) on small-scale sustainable farms could prevent the transmission of Salmonella and E. coli to nearby fresh produce fields. A 5-layer VB (31 × 49 m) was constructed between a dairy farm, a poultry farm, and a nearby produce field. Fresh produce (i.e., romaine lettuce and tomato), animal feces, and environmental (i.e., air, soil, and barrier) samples were collected for 15 months from 2018 to 2019. Four replicates of soil and fresh produce samples were taken from three plots located 10 m, 61 m, and 122 m away from the respective animal locations and processed for Salmonella and E. coli. Air and vegetative strip samples were sampled at 15-day intervals. Multiple colonies were processed from each positive sample, and a total of 143 positive Salmonella (n = 15) and E. coli (n = 128) isolates were retrieved from the soil, produce, air, and fecal samples. Interestingly, 18.2% of the Salmonella and E. coli isolates (n = 26) were recovered from fresh produce (n = 9) samples. Surprisingly, Salmonella isolates (n = 9) were only found in fecal (n = 3) samples collected from the dairy pasture. Data analysis suggests that the VB is an effective tool at reducing the transmission of E. coli and Salmonella from animal farms to fresh produce fields. However, based on phenotypic and genotypic testing, it is clear that fecal samples from animal farms are not the only source of pathogen contamination. This indicates that the environment (e.g., soil and wind), as well as the initial setup of the farm (e.g., proximity to service roads and produce plot placement), can contribute to the contamination of fresh produce. Our study recommends the need for more effective bioremediation and prevention control measures to use in conjunction with VBs to reduce pathogen transmission.


Assuntos
Infecções por Escherichia coli/transmissão , Escherichia coli/isolamento & purificação , Alface/microbiologia , Lycopersicon esculentum/microbiologia , Salmonelose Animal/transmissão , Salmonella/isolamento & purificação , Animais , Bovinos , Indústria de Laticínios , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/veterinária , Fazendas , Fezes/microbiologia , Aves Domésticas/microbiologia , Salmonella/crescimento & desenvolvimento
13.
Int J Food Microbiol ; 346: 109164, 2021 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-33813365

RESUMO

The aim of the study was to assess the presence of genes in ESBL-producing E. coli (ESBL-Ec) isolated from retail raw food in Nha Trang, Vietnam. A total of 452 food samples comprising chicken (n = 116), pork (n = 112), fish (n = 112) and shrimp (n = 112) collected between 2015 and 2017 were examined for the prevalence of ESBL-Ec. ESBL-Ec were detected in 46.0% (208/452) of retail food samples, particularly in 66.4% (77/116), 55.4% (62/112), 42.0% (47/112) 19.6% (22/112) of chicken, pork, fish and shrimp, respectively. Sixty-five out of the 208 (31.3%) ESBL-Ec isolates were positive for mcr genes including mcr-1, mcr-3 and both mcr-1 and mcr-3 genes in 56/208 (26.9%), 1/208 (0.5%) and 8/208 (3.9%) isolates, respectively. Particularly, there was higher prevalence of mcr-1 in ESBL-Ec isolates from chicken (53.2%, 41/77) in comparison to shrimp (22.7%, 5/22), pork (11.3%, 7/62) and fish (6.4%, 3/47). mcr-3 gene was detected in co-existence with mcr-1 in ESBL-Ec isolates from shrimp (9.1%, 2/22), pork (8.1%, 5/62) and fish (2.1%, 1/47) but not chicken. The 65 mcr-positive ESBL-Ec (mcr-ESBL-Ec) were colistin-resistant with the MICs of 4-8 µg/mL. All mcr-3 gene-positive isolates belonged to group A, whereas phylogenetic group distribution of isolates harboring only mcr-1 was B1 (44.6%), A (28.6%) and D (26.8%). PFGE analysis showed diverse genotypes, although some isolates demonstrated nearly clonal relationships. S1-PFGE and Southern hybridization illustrated that the mcr-1 and mcr-3 genes were located either on chromosomes or on plasmids. However, the types of mcr genes were harbored on different plasmids with varied sizes of 30-390 kb. Besides, the ESBL genes of CTX-M-1 or CTX-M-9 were also detected to be located on plasmids. Noteworthy, co-location of CTX-M-1 with mcr-1 or mcr-3 genes on the same plasmid was identified. The conjugation experiment indicated that the mcr-1 or mcr-3 was horizontally transferable. All mcr-ESBL-Ec isolates were multidrug resistance (resistance to ≥3 antimicrobial classes). Moreover, ß-Lactamase-encoding genes of the CTX-M-1 (78.5%), CTX-M-9 (21.5%), TEM (61.5%) groups were found in mcr-ESBL-Ec. The astA gene was detected in 27 (41.5%) mcr-ESBL-Ec isolates demonstrating their potential virulence. In conclusion, mcr-1 and mcr-3 genes existed individually or concurrently in ESBL-Ec isolates recovered from retail raw food in Nha Trang city, which might further complicate the antimicrobial-resistant situation in Vietnam, and is a possible health risk for human.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Proteínas de Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Carne/microbiologia , Alimentos Crus/microbiologia , beta-Lactamases/genética , Animais , Galinhas , Farmacorresistência Bacteriana , Escherichia coli/classificação , Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Peixes , Contaminação de Alimentos/análise , Contaminação de Alimentos/estatística & dados numéricos , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Filogenia , Plasmídeos/genética , Plasmídeos/metabolismo , Prevalência , Alimentos Crus/economia , Suínos , Vietnã , beta-Lactamases/metabolismo
14.
Nat Commun ; 12(1): 2464, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33927201

RESUMO

National-based prospective surveillance of all-age patients with acute diarrhea was conducted in China between 2009‒2018. Here we report the etiological, epidemiological, and clinical features of the 152,792 eligible patients enrolled in this analysis. Rotavirus A and norovirus are the two leading viral pathogens detected in the patients, followed by adenovirus and astrovirus. Diarrheagenic Escherichia coli and nontyphoidal Salmonella are the two leading bacterial pathogens, followed by Shigella and Vibrio parahaemolyticus. Patients aged <5 years had higher overall positive rate of viral pathogens, while bacterial pathogens were more common in patients aged 18‒45 years. A joinpoint analysis revealed the age-specific positivity rate and how this varied for individual pathogens. Our findings fill crucial gaps of how the distributions of enteropathogens change across China in patients with diarrhea. This allows enhanced identification of the predominant diarrheal pathogen candidates for diagnosis in clinical practice and more targeted application of prevention and control measures.


Assuntos
Diarreia/epidemiologia , Diarreia/patologia , Gastroenterite/epidemiologia , Gastroenterite/patologia , Adolescente , Adulto , Fatores Etários , Infecções por Caliciviridae/epidemiologia , Infecções por Caliciviridae/patologia , Criança , Pré-Escolar , China/epidemiologia , Diarreia/microbiologia , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/patologia , Gastroenterite/microbiologia , Humanos , Pessoa de Meia-Idade , Norovirus/isolamento & purificação , Rotavirus/isolamento & purificação , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/patologia , Salmonella/isolamento & purificação , Infecções por Salmonella/epidemiologia , Infecções por Salmonella/patologia , Shigella/isolamento & purificação , Vibrioses/epidemiologia , Vibrioses/patologia , Vibrio parahaemolyticus/isolamento & purificação , Adulto Jovem
15.
BMC Infect Dis ; 21(1): 388, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902477

RESUMO

BACKGROUND: One of the leading long-term complications of type 2 diabetes mellitus (T2DM) includes renal dysfunction and urinary tract infections (UTI) which are considered to be prevalent in uncontrolled diabetes. Moreover, physiological factors like age, gender, duration of diabetes, other diabetic complications like neuropathy, autonomic neuropathy and glycosuria are also considered as predisposing factors for increased prevalence of UTI in diabetes which can be symptomatic or asymptomatic. METHODS: This was a cross-sectional, multi-centre study including diabetic patients from 12 clinical sites spread across major cities of Pakistan. The inclusion criteria were adult Pakistani population of age between 18 to 75 years both genders and suffering from T2DM irrespective of duration. A detailed clinical history of the past 3 months was recorded and, biochemical investigations of blood samples were conducted. Urine culture analysis performed identified the type of pathogen present and was done only for asymptomatic patients. RESULTS: A total of 745 type 2 diabetic patients were initially screened, out of 545 patients considered for final analysis 501 (91.92%) were negative and the rest 44 (8.08%) had positive urine culture. Female gender had a significantly higher proportion of positive urine culture (77.27%, p-value< 0.001). Body mass index and mean age had insignificant distribution among the two groups of positive and negative urine culture, with age 40-59 years having higher proportion (70.45%) in the positive group. Escherichia coli was detected in most of the positive samples (52.3%). All bacterial samples were found resistant to Ciprofloxacin. CONCLUSION: Diabetic Pakistani muslim female patients are identified to be at high risk of suffering from asymptomatic UTI and age more than 40 years is an important risk factor. Escherichia coli was the most common causative organism among people living in this geographical area.


Assuntos
Infecções Assintomáticas/epidemiologia , Diabetes Mellitus Tipo 2/complicações , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/etiologia , Escherichia coli/isolamento & purificação , Islamismo , Infecções Urinárias/epidemiologia , Infecções Urinárias/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Estudos Transversais , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paquistão/epidemiologia , Prevalência , Fatores de Risco , Fatores Sexuais , Urinálise , Infecções Urinárias/microbiologia , Infecções Urinárias/urina , Adulto Jovem
16.
BMC Infect Dis ; 21(1): 385, 2021 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-33902489

RESUMO

BACKGROUND: Antibiotic resistance is often reported and great concerned as one of public health problems especially people living with poverty in developing countries including Thailand. The hill tribe people is defined as vulnerable population for antibiotic resistance in Thailand due to poor economic and education status particularly the Lahu people who is the second greatest group of the hill tribe people in Thailand. The study aimed to estimate the prevalence, factors associated with, and typing major species of bacteria with antibiotic drugs resistance among the Lahu hill tribe people in northern Thailand. METHODS: A cross-sectional study was conducted to gather the information from the participants. A validated questionnaire was used for data collection. Participants who presented an illness related to infectious diseases were eligible to participate the study and were asked to obtain specific specimen; sputum, urine or stool. Antibiotic susceptibility was tested by Kirbey Bauer's disc diffusion test. Chi-square and logistic regression were used to detect the associations between variables at the significant level of α = 0.05. RESULTS: A total of 240 participants were recruited into the study. The majority had urinary tract infection (67.9%) with two major pathogenic species of the infection; Escherichia coli (12.8%), and Enterobacter cloacae (8.0%). The prevalence of antibiotic resistance was 16.0%. Escherichia coli and Klebsiella pneumoniae species were found to have multidrug resistance that was greater than that of other species, while ampicillin was found to have the greatest drug resistance. It was found that those who had poor knowledge of antibiotic use had a 2.56-fold greater chance (95% CI = 1.09-5.32) of having antibiotic resistance than did those who had good knowledge of antibiotic use, and those who had poor antibiotic use behaviors had a 1.79-fold greater chance (95% CI = 1.06-4.80) of having antibiotic resistance than did those who had good antibiotic use behaviors. CONCLUSION: Effective public health interventions are urgently needed to reduce antibiotic drug resistance among the Lahu people by improving their knowledge and skills regarding the proper use of antibiotics and eventually minimizing antibiotic resistance. Moreover, health care professionals should strictly follow the standard guideline to prescribe antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Enterobacter cloacae/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/epidemiologia , Escherichia coli/efeitos dos fármacos , Grupos Étnicos , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/epidemiologia , Adolescente , Adulto , Idoso , Criança , Estudos Transversais , Enterobacter cloacae/isolamento & purificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Prevalência , Inquéritos e Questionários , Tailândia/epidemiologia , Tailândia/etnologia , Resultado do Tratamento , Infecções Urinárias/microbiologia , Adulto Jovem
18.
Actas urol. esp ; 45(2): 124-131, mar. 2021. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-201617

RESUMO

INTRODUCCIÓN Y OBJETIVO: La cistectomía radical es una cirugía compleja con una alta tasa de complicaciones, entre ellas las infecciones, conllevando un aumento de la morbimortalidad, estancia hospitalaria y costes. El objetivo de este trabajo es estudiar las infecciones relacionadas con la asistencia sanitaria (IRAS) en estos pacientes, así como de los microorganismos asociados, perfiles de resistencia antibiótica y factores de riesgo. MATERIAL Y MÉTODOS: Estudio prospectivo del 2012 al 2017. Se recogen variables epidemiológicas, comorbilidades y variables quirúrgicas. Se analizan los microorganismos implicados y patrones de susceptibilidad antibiótica. RESULTADOS: Estudio de 122 pacientes. Edad media 67 años (DE:18,42). Estancia hospitalaria media 23,5 días (18,42). Tasa de IRAS del 45%, predominando las infecciones del tracto urinario (43%) y de la herida quirúrgica (31%). Cultivos positivos en el 78,6% de los casos. Mayor aislamiento de Enterococcus (18%) y Escherichia coli (13%). El 43% de los microorganismos presentaban resistencia a la amoxicilina/ampicilina, 23% a las betalactamasas y 36% a las quinolonas. El tratamiento empírico fue adecuado en el 87,5%. Se observa un aumento en la estancia hospitalaria (17 días, p < 0,05) por padecer una IRAS. Menor tasa de complicaciones infecciosas en el abordaje laparoscópico frente al abierto (p < 0,001) y en las derivaciones ortotópicas frente al conducto ileal (p = 0,04). CONCLUSIONES: Encontramos una elevada tasa de IRAS en nuestra serie de cistectomías radicales, con un predominio de infecciones del tracto urinario y de la herida quirúrgica. E. coli y Enterococcus spp. son los microorganismos más frecuentemente aislados, con altas tasas de resistencia a algunos antibióticos de uso común


INTRODUCTION AND OBJECTIVE: Radical cystectomy is a complex surgery with a high rate of complications including infections, which lead to increased morbidity and mortality, longer hospital stay and higher costs. The aim of this work is to evaluate health care-associated infections (HAIs) in these patients, as well as associated microorganisms, antibiotic resistance profiles and risk factors. MATERIAL AND METHODS: Prospective study from 2012 to 2017. Epidemiologic variables, comorbidities and surgical variables are collected. The microorganisms involved and antibiotic susceptibility patterns are analyzed. RESULTS: 122 patients. Mean age 67 (SD:18,42). Mean hospital stay 23.5 days (18.42). HAIs rate of 45%, with predominant urinary tract infections (43%) and surgical wound infections (31%). Positive cultures in 78.6% of cases. Increased isolation of Enterococcus (18%) and Escherichia coli (13%). Forty-three percent of microorganisms were resistant to amoxicillin/ampicillin, 23% to beta-lactamases and 36% to quinolones. Empirical treatment was adequate in 87.5%. Hospital stay is increased (17 days, p < 0.05) due to HAIs. Lower rate of infectious complications in the laparoscopic vs. open approach (p < 0.001) and in orthotopic vs. ileal conduit diversion (p = 0.04) CONCLUSIONS: We found a high rate of HAIs in our radical cystectomy series, with predominant urinary tract and surgical wound infections. E.coli and Enterococcus spp. are the most frequently isolated microorganisms, with high rates of resistance to some commonly used antibiotics


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Cistectomia/efeitos adversos , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Estudos Prospectivos , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/microbiologia , Tempo de Internação , Fatores de Risco , Enterococcus/isolamento & purificação , Escherichia coli/isolamento & purificação , Espanha/epidemiologia , Resistência Microbiana a Medicamentos
19.
Arch Microbiol ; 203(5): 2541-2550, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33682076

RESUMO

The spread of multidrug-resistance in Gram-negative bacterial pathogens presents a major clinical challenge, and new approaches are required to combat these organisms. Nitric oxide (NO) is a well-known antimicrobial that is produced by the immune system in response to infection, and numerous studies have demonstrated that NO is a respiratory inhibitor with both bacteriostatic and bactericidal properties. However, given that loss of aerobic respiratory complexes is known to diminish antibiotic efficacy, it was hypothesised that the potent respiratory inhibitor NO would elicit similar effects. Indeed, the current work demonstrates that pre-exposure to NO-releasers elicits a > tenfold increase in IC50 for gentamicin against pathogenic E. coli (i.e. a huge decrease in lethality). It was therefore hypothesised that hyper-sensitivity to NO may have arisen in bacterial pathogens and that this trait could promote the acquisition of antibiotic-resistance mechanisms through enabling cells to persist in the presence of toxic levels of antibiotic. To test this hypothesis, genomics and microbiological approaches were used to screen a collection of E. coli clinical isolates for antibiotic susceptibility and NO tolerance, although the data did not support a correlation between increased carriage of antibiotic resistance genes and NO tolerance. However, the current work has important implications for how antibiotic susceptibility might be measured in future (i.e. ± NO) and underlines the evolutionary advantage for bacterial pathogens to maintain tolerance to toxic levels of NO.


Assuntos
Aminoglicosídeos/farmacologia , Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Óxido Nítrico/farmacologia , Evolução Biológica , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Gentamicinas/farmacologia , Humanos , Testes de Sensibilidade Microbiana
20.
Transplant Proc ; 53(4): 1281-1283, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33775418

RESUMO

Fournier gangrene is a progressive necrotizing infection of the external genitalia or perineum that constitutes a urologic emergency. Incidence of Fournier gangrene is rising because of population aging, increasing comorbidities, and widespread use of immunosuppressive therapy, including immunosuppressive regimens used in kidney transplants. This is a rapidly progressive and potentially lethal disease without treatment, and early recognition of the disease, proper management of the predisposing factors, and aggressive surgical debridement are the most essential interventions. We report a rare case of Fournier gangrene in the early postoperative period of a kidney transplant due to a perinephric abscess.


Assuntos
Abscesso Abdominal/microbiologia , Gangrena de Fournier/microbiologia , Transplante de Rim/efeitos adversos , Perinefrite/microbiologia , Complicações Pós-Operatórias/microbiologia , Abscesso Abdominal/cirurgia , Idoso , Desbridamento , Enterococcus faecalis/isolamento & purificação , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/cirurgia , Gangrena de Fournier/cirurgia , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/cirurgia , Humanos , Masculino , Perinefrite/cirurgia , Complicações Pós-Operatórias/cirurgia
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