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1.
J Zoo Wildl Med ; 51(4): 761-770, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33480556

RESUMO

Increase of antimicrobial resistance (AMR) is a global threat to health. The AMR profile of bacteria isolated from domesticated animals and free-ranging wildlife has been studied, but there are relatively few studies of bacteria isolated from captive wild animals. Understanding the dynamics of AMR in different populations is key to minimizing emergence of resistance and to preserve the efficacy of antimicrobials. In this study, fecal samples were collected from 17 species of healthy ungulates from a zoological collection in southeast England, which yielded 39 Escherichia coli and 55 Enterococcus spp. isolates for further analysis. Antibiotic sensitivity was investigated using agar disk diffusion. Escherichia coli isolates were resistant to a range of antibiotics, with resistance to ampicillin being the most common (28%). All E. coli isolates were susceptible to apramycin, enrofloxacin, chloramphenicol, and florfenicol. None tested positive for extended-spectrum beta-lactamase or AmpC activity. Seven of 39 (18%) E. coli isolates were resistant to three or more antibiotic classes. The E. coli isolates were further analyzed using multilocus sequence typing, which identified four pairs of identical sequence type isolates and 27 diverse strains. The Enterococcus spp. isolates were resistant to a range of antibiotics, with resistance to cefpodoxime seen in 95% of isolates. All Enterococcus spp. isolates were susceptible to ampicillin, gentamicin, chloramphenicol, and vancomycin. This study identified multidrug-resistant phenotypes in enterobacterial isolates that were like those commonly found in domestic ungulates. There was no apparent spatial clustering of the resistance profiles within the zoo. Review of the medical records of individual animals showed no direct relation to the AMR profiles observed. Observed resistance to antibiotics rarely or never used may have been due to coselection or directly acquired from other sources.


Assuntos
Antibacterianos/farmacologia , Artiodáctilos/microbiologia , Enterococcus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Perissodáctilos/microbiologia , Animais , Animais de Zoológico , Farmacorresistência Bacteriana , Enterococcus/classificação , Tipagem de Sequências Multilocus , Reino Unido
2.
BMC Infect Dis ; 20(1): 356, 2020 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-32517758

RESUMO

BACKGROUND: Vancomycin-resistant Enterococcus spp. (VRE) have spread all over the world. The present study aims to investigate the species distribution, specimen type and susceptibilities of Enterococcal species collected from Nanjing Drum Tower Hospital from 2013 to 2018. Additionally, distribution of VRE and prevalence of van gene among VRE isolates were also analyzed. METHODS: The susceptibilities of 3913 Enterococcus isolates were retrospectively investigated. Among these strains, 60 VRE strains were further anazlyed in this study. The minimum inhibitory concentrations (MICs) of the VRE strains towards vancomycin, teicoplanin and linezolid were determined by E-test. Polymerase chain reaction (PCR) and DNA sequencing were used to investigate the prevalence of van genes among VRE. Furthermore, the sequence types (STs) of VRE strains were explored by multi-locus sequence typing (MLST). RESULTS: Among the 3913 enterococci isolates, Enterococcus faecalis (n = 1870, 47.8%) and Enterococcus faecium (1738, 44.4%) were the main isolates. These Enterococcus strains were mainly isolated from urine (n = 1673, 42.8%), followed by secretions (n = 583, 14.9%) and ascites (n = 554, 14.2%). VRE displayed a decreasing trend year by year. Molecular analysis revealed that 49 out of 60 VRE isolates carried vanA gene, 10 carried vanM, and 1 carried both vanA and vanM genes. Sixteen distinct STs were identified among the 58 VREM, with ST78 (n = 16), ST192 (n = 8) and ST570 (n = 7) being the most dominant ones. CONCLUSIONS: E. faecalis and E. faecium were the major enterococci strains which are the main pathogens of urinary traction infections; vanA and vanM were the main determinants conferring resistance to vancomycin; ST78, ST192 and ST570 were the leading STs of VREM which displayed a decreasing trend of prevalence year by year.


Assuntos
Enterococcus/isolamento & purificação , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina/isolamento & purificação , Antibacterianos/farmacologia , China , DNA Bacteriano/metabolismo , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/isolamento & purificação , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/isolamento & purificação , Infecções por Bactérias Gram-Positivas/diagnóstico , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Estudos Retrospectivos , Centros de Atenção Terciária , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/genética
3.
Appl Environ Microbiol ; 86(16)2020 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-32503913

RESUMO

Triclocarban (TCC), a formerly used disinfectant, kills bacteria via an unknown mechanism of action. A structural hallmark is its N,N'-diaryl urea motif, which is also present in other antibiotics, including the recently reported small molecule PK150. We show here that, like PK150, TCC exhibits an inhibitory effect on Staphylococcus aureus menaquinone metabolism via inhibition of the biosynthesis protein demethylmenaquinone methyltransferase (MenG). However, the activity spectrum (MIC90) of TCC across a broad range of multidrug-resistant staphylococcus and enterococcus strains was much narrower than that of PK150. Accordingly, TCC did not cause an overactivation of signal peptidase SpsB, a hallmark of the PK150 mode of action. Furthermore, we were able to rule out inhibition of FabI, a confirmed target of the diaryl ether antibiotic triclosan (TCS). Differences in the target profiles of TCC and TCS were further investigated by proteomic analysis, showing complex but rather distinct changes in the protein expression profile of S. aureus Downregulation of the arginine deiminase pathway provided additional evidence for an effect on bacterial energy metabolism by TCC.IMPORTANCE TCC's widespread use as an antimicrobial agent has made it a ubiquitous environmental pollutant despite its withdrawal due to ecological and toxicological concerns. With its antibacterial mechanism of action still being unknown, we undertook a comparative target analysis between TCC, PK150 (a recently discovered antibacterial compound with structural resemblance to TCC), and TCS (another widely employed chlorinated biphenyl antimicrobial) in the bacterium Staphylococcus aureus We show that there are distinct differences in each compound's mode of action, but also identify a shared target between TCC and PK150, the interference with menaquinone metabolism by inhibition of MenG. The prevailing differences, however, which also manifest in a remarkably better broad-spectrum activity of PK150, suggest that even high levels of TCC or TCS resistance observed by continuous environmental exposure may not affect the potential of PK150 or related N,N'-diaryl urea compounds as new antibiotic drug candidates against multidrug-resistant infections.


Assuntos
Proteínas de Bactérias/genética , Carbanilidas/farmacologia , Desinfetantes/farmacologia , Enterococcus/efeitos dos fármacos , Metiltransferases/genética , Staphylococcus aureus/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Enterococcus/genética , Enterococcus/metabolismo , Metiltransferases/metabolismo , Staphylococcus aureus/genética , Staphylococcus aureus/metabolismo
4.
Ecotoxicol Environ Saf ; 200: 110767, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32470679

RESUMO

The occurrence and dissemination of antibiotic resistant genes (ARGs) that are associated with clinical pathogens and the evaluation of associated risks are still under-investigated in developing countries under tropical conditions. In this context, cultivable and molecular approaches were performed to assess the dissemination of bacteria and the antibiotic resistance genes in aquatic environment in Kinshasa, Democratic Republic of the Congo. Cultivable approach quantified ß-lactam, carbapenem resistant, and total Escherichia coli and Enterobacteriaceae in river sediments and surface waters that receive raw hospital effluents. The molecular approach utilized Quantitative Polymerase Chain Reaction (qPCR) to quantify the total bacteria and the richness of relevant bacteria (Escherichia coli, Enterococcus, and Pseudomonas), and antibiotic resistance genes (ARGs: blaOXA-48, blaCTX-M, blaIMP, blaTEM) in sediment samples. Statistical analysis were employed to highlight the significance of hospital contribution and seasonal variation of bacteria and ARGs into aquatic ecosystems in suburban municipalities of Kinshasa, Democratic Republic of the Congo. The contribution of hospitals to antibiotic resistance proliferation is higher in the dry season than during the wet season (p < 0.05). Hospital similarly contributed Escherichia coli, Enterococcus, and Pseudomonas and ARGs significantly to the sediments in both seasons (p < 0.05). The organic matter content correlated positively with E. coli (r = 0.50, p < 0.05). The total bacterial load correlated with Enterococcus, and Pseudomonas (0.49 < r < 0.69, p < 0.05). Each ARG correlated with the total bacterial load or at least one relevant bacteria (0.41 < r < 0.81, p < 0.05). Our findings confirm that hospital wastewaters contributed significantly to antibiotic resistance profile and the significance of this contribution increased in the dry season. Moreover, our analysis highlights this risk from untreated hospital wastewaters in developing countries, which presents a great threat to public health.


Assuntos
Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/efeitos dos fármacos , Hospitais , Rios/microbiologia , Águas Residuárias/microbiologia , Antibacterianos/análise , Antibacterianos/farmacologia , Cidades , República Democrática do Congo , Ecossistema , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Pseudomonas/efeitos dos fármacos , Pseudomonas/genética , Rios/química , Clima Tropical , Águas Residuárias/química
6.
Lett Appl Microbiol ; 71(1): 3-25, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32304575

RESUMO

Surface water is prone to bacterial contamination as it receives wastes and pollutants from human and animal sources, and contaminated water may expose local populations to health risks. This review provides a brief overview on the prevalence and antimicrobial resistance (AR) phenotypes of Salmonella, Escherichia coli and Enterococcus, found in natural freshwaters. These bacteria are frequently detected in surface waters, sometimes as etiological agents of waterborne infections, and AR strains are not uncommonly identified in both developed and developing countries. Data relating to Salmonella, E. coli and Enterococcus present in environmental water are lacking, and in order to understand their development and dissemination using the One Health approach, understanding the prevalence, distribution and characteristics of the bacteria present in surface water as well as their potential sources is important. Furthermore, AR bacteria in natural watersheds are not well investigated and their impacts on human health and food safety are not well understood. As surface water is a receptacle for AR bacteria from human and animal sources and a vehicle for their dissemination, this is a crucial data gap in understanding AR and minimizing its spread. For this review, Salmonella, E. coli and Enterococcus were chosen to evaluate the presence of primary pathogens and opportunistic pathogens as well as to monitor AR trends in the environmental water. Studies around the world have demonstrated the widespread distribution of pathogenic and AR bacteria in surface waters of both developing and developed countries, confirming the importance of environmental waters as a reservoir for these bacteria and the need for more attention on the environmental bacteria for emerging AR.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Enterococcus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Salmonella/efeitos dos fármacos , Animais , Enterococcus/genética , Enterococcus/isolamento & purificação , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Água Doce/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Fenótipo , Prevalência , Salmonella/genética , Salmonella/isolamento & purificação , Poluição da Água
7.
J Anim Sci ; 98(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32277238

RESUMO

A 42-d experiment was conducted to evaluate the effect of Cu and Zn source and Cu level on pig performance, mineral status, bacterial modulation, and the presence of antimicrobial-resistant genes in isolates of Enterococcus spp. At weaning, 528 pigs (5.9 ± 0.50 kg) were allotted to 48 pens of a randomized complete block design in a 2 × 2 factorial arrangement with two Cu and Zn sources (SF: sulfate and HCl: hydroxychloride) and two Cu levels (15 and 160 mg/kg). As a challenge, the pigs were reared in dirty pens used by a previous commercial batch. Two-phase diets were offered: the pre-starter (PS) phase from day 1 to 14 and the starter phase (ST) from day 14 to 42. At days 14 and 42, pigs were individually weighed and blood samples from one pig per pen were taken. At the end of the experiment, one pig per pen was euthanized to collect the samples. Feeding high levels of Cu increased body weight (BW) from 16.6 to 17.7 kg (P < 0.001). Furthermore, average daily gain, gain to feed (G:F) ratio, average daily feed intake (ADFI), and mineral status were enhanced with Cu at 160 mg/kg (P < 0.05) compared with Cu at 15 mg/kg. There was no effect of the interaction between source × level on any of the growth performance responses except for ADFI (P = 0.004) and G:F (P = 0.029) at the end of the ST period and for G:F (P = 0.006) for entire nursery period (day 0 to 42). At the end of the ST period, pigs fed Cu at 160 mg/kg as HCl had not only higher ADFI but also lower G:F than those fed Cu as SF at 160 mg/kg. Meanwhile, for the entire nursery period, G:F did not differ between pigs fed Cu at 160 mg/kg as HCl or SF. In colonic digesta, the relative abundance of Streptococcus, Enterobacter, Escherichia, among others, decreased (P-adjust < 0.05), while Lachnospira and Roseburia tended (P-adjust < 0.10) to increase in pigs fed Cu at 160 mg/kg as HCl compared with those fed Cu SF at 160 mg/kg. An increase (P-adjust < 0.05) in Methanosphaera and Roseburia was observed in pigs fed Cu at 160 mg/kg. From colon digesta, Enterococcus spp. was isolated in 40 samples, being E. faecalis the most dominating (65%) regardless of the experimental diet. Genes of ermB (7.5%) and tetM (5%) were identified. No genes for Cu (tcrB) or vancomycin (vanA, vanB, vanC1, and vanC2) were detected. In conclusion, European Union permissible levels of Cu (160 mg/kg), of both sources, were able to increase performance, mineral status, and bacterial modulation compared with nutritional level. Different effects on growth performance, mineral tissue content, and microbial modulation were observed between Cu and Zn sources.


Assuntos
Cobre/farmacologia , Farmacorresistência Bacteriana/genética , Enterococcus/efeitos dos fármacos , Microbioma Gastrointestinal/efeitos dos fármacos , Suínos/fisiologia , Zinco/farmacologia , Ração Animal/análise , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Dieta/veterinária , Enterococcus/isolamento & purificação , Feminino , Microbioma Gastrointestinal/genética , Masculino , Distribuição Aleatória , Suínos/genética , Suínos/crescimento & desenvolvimento , Suínos/microbiologia , Desmame
8.
BMC Vet Res ; 16(1): 109, 2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32272916

RESUMO

BACKGROUND: Antimicrobial resistance is becoming increasingly important in both human and veterinary medicine. According to the One Health concept, an important step is to monitor the resistance patterns of pathogenic bacteria. In this study, the antimicrobial susceptibility patterns and trends of bacteria isolated from stray cats, hospital-admitted cats, and veterinary staff in South Korea between 2017 and 2018 were investigated. RESULTS: The minimum inhibitory concentrations of different antibiotics for Staphylococcus spp., Enterobacteriaceae, and Enterococcus spp. were determined to establish representatives of different antibiotic classes relevant for treatment or surveillance. For Coagulase-positive and Coagulase-negative Staphylococci, resistance to fluoroquinolones was below 13%, but resistance to ampicillin and penicillin was high (20-88%). A total of 9.5, 12.1, and 40.3% of staphylococcal isolates from stray cats, hospital-admitted cats, and veterinary staff, respectively, were confirmed to be mecA positive. For Enterobacteriaceae, resistance to carbapenems, fluoroquinolones, and 3rd generation cephalosporins was low (0-11.1%). The Enterococcus spp. isolates showed no resistance to vancomycin. The antimicrobial resistance rates of the Staphylococcus spp. and Enterobacteriaceae isolates from stray cats were usually lower than those of isolates from hospital-admitted cats and veterinary staff, but the Enterococcus spp. isolates revealed the opposite. Thus, the antimicrobial resistance varied across bacterial species according to the source from which they were isolated. CONCLUSIONS: Resistance to critically important compounds were low. However, the presence of antimicrobial resistance in cat isolates is of both public health and animal health concern.


Assuntos
Antibacterianos/farmacologia , Gatos/microbiologia , Farmacorresistência Bacteriana , Técnicos em Manejo de Animais , Animais , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Enterococcus/efeitos dos fármacos , Enterococcus/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , República da Coreia , Staphylococcus/efeitos dos fármacos , Staphylococcus/isolamento & purificação , Médicos Veterinários
9.
Artigo em Inglês | MEDLINE | ID: mdl-32178603

RESUMO

From 1 January to 31 December 2018, thirty-six institutions around Australia participated in the Australian Enterococcal Sepsis Outcome Programme (AESOP). The aim of AESOP 2018 was to determine the proportion of enterococcal bacteraemia isolates in Australia that were antimicrobial resistant, and to characterise the molecular epidemiology of the E. faecium isolates. Of the 1,248 unique episodes of bacteraemia investigated, 93.5% were caused by either E. faecalis (54.2%) or E. faecium (39.3%). Ampicillin resistance was not detected in E. faecalis but was detected in 89.4% of E. faecium. Vancomycin non-susceptibility was not detected in E. faecalis but was reported in 45.0% of E. faecium. Overall 49.3% of E. faecium isolates harboured vanA or vanB genes. Of the vanA/vanB positive E. faecium isolates, 52.9% harboured vanA genes and 46.2% vanB genes; 0.8% harboured both vanA and vanB genes. The percentage of E. faecium bacteraemia isolates resistant to vancomycin in Australia is substantially higher than that seen in most European countries. E. faecium consisted of 59 multilocus sequence types (STs) of which 74.4% of isolates were classified into six major STs containing ten or more isolates. All major STs belong to clonal cluster (CC) 17, a major hospital-adapted polyclonal E. faecium cluster. The predominant STs (ST17, ST1424, ST796, ST80, ST1421, and ST262) were found across most regions of Australia. The most predominant clone was ST17 which was identified in all regions except the Australian Capital Territory and the Northern Territory. Overall, 55.8% of isolates belonging to the six predominant STs harboured vanA or vanB genes. The AESOP 2018 study has shown that enterococcal bacteraemias in Australia are frequently caused by polyclonal ampicillin-resistant high-level gentamicin-resistant vanA- or vanB-harbouring E. faecium which have limited treatment options.


Assuntos
Antibacterianos , Bacteriemia , Enterococcus faecium , Enterococcus , Sepse , Antibacterianos/farmacologia , Território da Capital Australiana , Bacteriemia/epidemiologia , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/isolamento & purificação , Humanos , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Northern Territory , Sepse/epidemiologia , Sepse/microbiologia
10.
Sci Rep ; 10(1): 3937, 2020 03 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127598

RESUMO

For a One-Health investigation of antimicrobial resistance (AMR) in Enterococcus spp., isolates from humans and beef cattle along with abattoirs, manured fields, natural streams, and wastewater from both urban and cattle feedlot sources were collected over two years. Species identification of Enterococcus revealed distinct associations across the continuum. Of the 8430 isolates collected, Enterococcus faecium and Enterococcus faecalis were the main species in urban wastewater (90%) and clinical human isolates (99%); Enterococcus hirae predominated in cattle (92%) and feedlot catch-basins (60%), whereas natural streams harbored environmental Enterococcus spp. Whole-genome sequencing of E. faecalis (n = 366 isolates) and E. faecium (n = 342 isolates), revealed source clustering of isolates, indicative of distinct adaptation to their respective environments. Phenotypic resistance to tetracyclines and macrolides encoded by tet(M) and erm(B) respectively, was prevalent among Enterococcus spp. regardless of source. For E. faecium from cattle, resistance to ß-lactams and quinolones was observed among 3% and 8% of isolates respectively, compared to 76% and 70% of human clinical isolates. Clinical vancomycin-resistant E. faecium exhibited high rates of multi-drug resistance, with resistance to all ß-lactam, macrolides, and quinolones tested. Differences in the AMR profiles among isolates reflected antimicrobial use practices in each sector of the One-Health continuum.


Assuntos
Antibacterianos/farmacologia , Enterococcus/patogenicidade , Farmacorresistência Bacteriana/genética , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecalis/patogenicidade , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/patogenicidade , Humanos , Macrolídeos/farmacologia , Filogenia , Quinolonas/farmacologia , Tetraciclinas/farmacologia , Virulência , Sequenciamento Completo do Genoma , Resistência beta-Lactâmica/genética
11.
J Med Chem ; 63(6): 3161-3171, 2020 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-32097000

RESUMO

Increased usage of daptomycin to treat infections caused by Gram-positive bacterial pathogens has resulted in emergence of resistant mutants. In a search for more effective daptomycin analogues through medicinal chemistry studies, we found that methylation at the nonproteinogenic amino acid kynurenine in daptomycin could result in significant enhancement of antibacterial activity. Termed "kynomycin," this new antibiotic exhibits higher antibacterial activity than daptomycin and is able to eradicate methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE) strains, including daptomycin-resistant strains. The improved antimicrobial activity of kynomycin was demonstrated in in vitro time-killing assay, in vivo wax worm model, and different mouse infection models. The increased antibacterial activity, improved pharmacokinetics, and lower cytotoxicity of kynomycin, compared to daptomycin, showed the promise of the future design and development of next-generation daptomycin-based antibiotics.


Assuntos
Antibacterianos/uso terapêutico , Depsipeptídeos/uso terapêutico , Lipopeptídeos/uso terapêutico , Infecções Estafilocócicas/tratamento farmacológico , Animais , Antibacterianos/síntese química , Antibacterianos/farmacocinética , Antibacterianos/toxicidade , Permeabilidade da Membrana Celular/efeitos dos fármacos , Daptomicina/química , Daptomicina/uso terapêutico , Depsipeptídeos/síntese química , Depsipeptídeos/farmacocinética , Depsipeptídeos/toxicidade , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus/efeitos dos fármacos , Feminino , Células HEK293 , Humanos , Lepidópteros/efeitos dos fármacos , Lepidópteros/microbiologia , Lipopeptídeos/síntese química , Lipopeptídeos/farmacocinética , Lipopeptídeos/toxicidade , Masculino , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Metilação , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos ICR , Testes de Sensibilidade Microbiana
12.
Prev Vet Med ; 176: 104934, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32109782

RESUMO

BACKGROUND: Tylosin is a commonly used in-feed antimicrobial and is approved in several countries to reduce the incidence of liver abscesses in beef cattle. Macrolides are critically important antimicrobials in human health and used to treat some foodborne bacterial diseases, such as Campylobacter jejuni and Salmonella. Feeding tylosin could select for resistant enteric bacteria in cattle, which could contaminate beef products at slaughter and potentially cause foodborne illness. We conducted a systematic review and meta-analysis to evaluate the impact of feeding tylosin to cattle on phenotypic and genotypic resistance in several potential zoonotic enteric bacteria: Enterococcus species, Escherichia coli, Salmonella enterica subspecies enterica, and Campylobacter species. This review was registered with PROSPERO (#CRD42018085949). RESULTS: Eleven databases were searched for primary research studies that fed tylosin at approved doses to feedlot cattle and tested bacteria of interest for phenotypic or genotypic resistance. We screened 1,626 citations and identified 13 studies that met the inclusion criteria. Enterococcus species were tested in seven studies, Escherichia coli was isolated in five studies, three studies reported on Salmonella, and two studies reported on Campylobacter species. Most studies relied on phenotypic antimicrobial susceptibility testing and seven also reported resistance gene testing. A random-effects meta-analyses of erythromycin-resistant enterococci from four studies had significant residual heterogeneity. Only two studies were available for a meta-analysis of tylosin-resistant enterococci. A semi-quantitative analysis demonstrated an increase in macrolide-resistant enterococci after long durations of tylosin administration (>100 days). Semi-quantitative analyses of other bacteria-antimicrobial combinations revealed mixed results, but many comparisons found no effect of tylosin administration. However, about half of these no-effect comparisons did not record the cumulative days of tylosin administration or the time since the last dose. CONCLUSIONS: When fed at approved dosages for typical durations, tylosin increases the proportion of macrolide-resistant enterococci in the cattle gastrointestinal tract, which could pose a zoonotic risk to human beef consumers. Feeding tylosin for short durations may mitigate the impact on macrolide-resistant enterococci and further studies are encouraged to determine the effect of minimizing or eliminating tylosin use in beef cattle. There may also be an impact on other bacteria and other antimicrobial resistances but additional details or data are needed to strengthen these comparisons. We encourage authors of antimicrobial-resistance studies to follow reporting guidelines and publish details of all comparisons to strengthen future meta-analyses.


Assuntos
Antibacterianos/administração & dosagem , Campylobacter/efeitos dos fármacos , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Salmonella/efeitos dos fármacos , Tilosina/administração & dosagem , Animais , Bovinos , Feminino , Microbioma Gastrointestinal/efeitos dos fármacos , Masculino
13.
J Anim Sci ; 98(3)2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-31950170

RESUMO

Studies suggest a link between added copper (Cu) and co-selection of antimicrobial resistance (AMR) in Enterococcus spp., but data are inconsistent. This study aimed to assess the impact of added Cu, alone or with a feed-grade antimicrobial, on growth performance, transferable Cu resistance gene (tcrB) prevalence, abundance of tcrB in fecal community DNA, and AMR in fecal enterococci in weaned piglets. A total of 320 barrows (DNA 200 × 400, DNA Genetics) weaned at approximately 21 d of age with 7.4 kg (7.4 ±â€…0.06 kg) BW were used in a 28-d study. Piglets were fed a common non-medicated diet for 7 d of acclimation. Treatments were arranged in a 2 × 2 factorial design with main effects of added Cu (0 vs. 200 mg/kg Cu from Cu sulfate) and chlortetracycline (0 vs. 440 mg/kg CTC). Growth performance and fecal samples were obtained on days 0, 14, and 28. There was no evidence (P > 0.05) for Cu and CTC interaction in growth performance. Pigs fed diets with added Cu had increased (P < 0.05) ADG and ADFI from days 0 to 14, with no evidence for differences (P > 0.05) from days 15 to 28 and 0 to 28. Pigs fed diets with CTC had improved (P < 0.01) ADG, ADFI, and G:F from days 0 to 28. Prevalence of tcrB-positive enterococci was not affected by the addition of Cu and/or CTC (P > 0.05). Prevalence of tcrB-positive enterococci was higher on day 14 than other sampling days (P = 0.002). Prevalence of tetracycline resistance gene [tet(M)]-positive enterococci was not affected by treatments or day (P > 0.05). Prevalence of macrolide resistance gene [erm(B)]-positive enterococci had a significant treatment and sampling day interaction (P = 0.021). The abundance of the tcrB gene in feces, quantified by PCR, was not affected by Cu treatment. The median Cu minimum inhibitory concentrations (MIC) of tcrB-negative and -positive isolates were 3 and 20 mM, respectively (P < 0.001). For day 0 and day 28, all Enterococcus isolates were susceptible to gentamicin, kanamycin, streptomycin, daptomycin, and tigecycline, with a majority of isolates resistant to chloramphenicol, erythromycin, lincomycin, linezolid, tetracycline, tylosin tartrate, and Synercid. In conclusion, 200 mg/kg added Cu or 440 mg/kg CTC in nursery diets improved growth performance of nursery pigs. Added Cu, with or without a selection pressure of CTC, did not increase Cu-resistant enterococci and did not co-select resistance to antibiotics.


Assuntos
Clortetraciclina/farmacologia , Cobre/farmacologia , Enterococcus/efeitos dos fármacos , Fezes/microbiologia , Suínos/crescimento & desenvolvimento , Ração Animal/análise , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/farmacologia , Clortetraciclina/administração & dosagem , Cobre/administração & dosagem , Dieta/veterinária , Farmacorresistência Bacteriana/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana/veterinária
14.
PLoS One ; 15(1): e0225077, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31951610

RESUMO

BACKGROUND: The data on infective endocarditis after transcatheter aortic valve implantation (TAVI) is scarce and limited to case reports and case series in the literature. It is the need of the hour to analyze the available data on post-TAVI infective endocarditis from the available literature. The objectives of this systematic review were to evaluate the incidence of infective endocarditis after transcatheter aortic valve implantation, its microbiological profile and clinical outcomes. It will help us to improve the antibiotic prophylaxis strategies and treatment options for infective endocarditis in the context of TAVI. METHODS: EMBASE, Medline and the CENTRAL trials registry of the Cochrane Collaboration were searched for articles on infective endocarditis in post-TAVI patients till October 2018. Eleven articles were included in the systematic review. The outcomes assessed werethe incidence of infective endocarditis, its microbiological profile andclinical outcomes including major adverse cardiac event (MACE), net adverse clinical event (NACE), surgical intervention and valve-in-valve procedure. RESULTS: The incidence of infective endocarditis varied from 0%-14.3% in the included studies, the mean was3.25%. The average duration of follow-up was 474 days (1.3 years). Enterococci were the most common causative organism isolated from 25.9% of cases followed by Staphylococcus aureus (16.1%) and coagulase-negative Staphylococcus species (14.7%). The mean in-hospital mortality and mortality at follow-up was 29.5% and 29.9%, respectively. The cumulative incidence of heart failure, stroke and major bleeding were 37.1%, 5.3% and 11.3%,respectively. Only a single study by Martinez-Selles et al. reported arrhythmias in 20% cases. The septic shock occurred in 10% and 27.7% post-TAVI infective endocarditis patients according to 2 studies. The surgical intervention and valve-in-valve procedure were reported in 11.4% and 6.4% cases, respectively. CONCLUSION: The incidence of post-TAVI infective endocarditis is low being 3.25% but it is associated with high mortality and complications. The most common complication is heart failure with a cumulative incidence of 37.1%. Enterococciare the most common causative organism isolated from 25.9% of cases followed by Staphylococcus aureus in 16.1% of cases. Appropriate measures should be taken to prevent infective endocarditis in post-TAVI patients including adequate antibiotics prophylaxis directed specifically against these organisms. STUDY REGISTRATION: PROSPERO registration number CRD42018115943.


Assuntos
Endocardite Bacteriana/microbiologia , Endocardite/microbiologia , Infecções Relacionadas à Prótese/microbiologia , Infecções Estafilocócicas/microbiologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Antibioticoprofilaxia/métodos , Endocardite/tratamento farmacológico , Endocardite/epidemiologia , Endocardite/patologia , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/epidemiologia , Endocardite Bacteriana/patologia , Enterococcus/efeitos dos fármacos , Enterococcus/patogenicidade , Feminino , Próteses Valvulares Cardíacas/microbiologia , Mortalidade Hospitalar , Humanos , Masculino , Pessoa de Meia-Idade , Infecções Relacionadas à Prótese/tratamento farmacológico , Infecções Relacionadas à Prótese/epidemiologia , Infecções Relacionadas à Prótese/patologia , Fatores de Risco , Caracteres Sexuais , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/patologia , Staphylococcus aureus/patogenicidade , Substituição da Valva Aórtica Transcateter/efeitos adversos , Resultado do Tratamento
15.
Molecules ; 25(2)2020 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-31936589

RESUMO

Anaerobic digestion (AD) is a commonly used method of processing waste. Regardless of the type of the used digestate (fertilizer, feedstock in case of solid-state fermentation, raw-material in case of thermal treatment) effective pathogen risk elimination, even in the case of high pathogen concentration is essential. An investigation of the survival time and inactivation rate of the Salmonella Senftenberg W775, Enterococcus spp., and Ascaris suum eggs during thermophilic anaerobic digestion performed on laboratory scale and confirmation of hygienization in full-scale operation were performed in this study. Except for sanitization efficiency, the AD process performance and stability were also verified based on determination of pH value, dry matter content, acidity, alkalinity, and content of fatty acids. The elimination of pathogen was met within 6.06 h, 5.5 h, and about 10 h for the Salmonella Senftenberg W775, Enterococcus spp., and Ascaris suum, respectively in the laboratory trials. The obtained results were confirmed in full-scale tests, using 1500 m3 Kompogas® reactors, operating in MBT Plant located in Poland. Sanitization of the digestate was achieved. Furthermore, the process was stable. The pH value, suspended solids, and ammonium content remained stable at 8.5, 35%, and 3.8 g/kg, respectively. The acetic acid content was noted between almost 0.8 and over 1.1 g/kg, while the concentration of propionic acid was noted at maximum level of about 100 mg/kg. The AD conditions could positively affect the pathogen elimination. Based on these results it can be found that anaerobic digestion under thermophilic conditions results in high sanitation efficiency.


Assuntos
Reatores Biológicos , Eliminação de Resíduos/normas , Saneamento/métodos , Esgotos/microbiologia , Anaerobiose , Animais , Ascaris suum/efeitos dos fármacos , Ascaris suum/patogenicidade , Enterococcus/efeitos dos fármacos , Enterococcus/patogenicidade , Ácidos Graxos/química , Ácidos Graxos/metabolismo , Fermentação , Fertilizantes/microbiologia , Microbiologia de Alimentos , Humanos , Polônia , Salmonella/efeitos dos fármacos , Salmonella/patogenicidade , Resíduos Sólidos
16.
Int J Food Microbiol ; 319: 108509, 2020 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-31945714

RESUMO

The role of plant-based foods in the epidemiology of antimicrobial resistance has been inadequately studied. In this investigation, resistant organisms from vegetables, fruits and spices imported into Canada were identified and characterized. A total of 143 products imported from primarily Asian and African countries were purchased from international markets in Saskatoon, Saskatchewan. Samples were selectively cultured for bacterial species where resistance is known to be emerging. The proportions of samples positive for each organism were as follows: E. coli (n = 13, 9.1%), Salmonella spp. (n = 2, 1.4%), ESBL producing Enterobacter spp. (n = 2, 1.4%) and K. pneumoniae (n = 2, 1.4%), S. aureus (n = 7, 4.9%) and Enterococcus spp. (n = 66, 46.2%). Antimicrobial minimum inhibitory concentrations were determined by broth micro-dilution and agar-dilution. Based on the susceptibility of each organism, isolates were screened for resistance genes (ß-lactamases and plasmid mediated quinolones resistance determinants) by PCR. Extended-spectrum ß-lactamase producing Enterobacteriaceae and methicillin resistant S. aureus (MRSA) were identified from 6/143 (4.2%) and 2/143 (1.4%) of samples respectively. The qnrB, qnrS and aac(6')-Ib-cr plasmid mediated quinolone resistance determinants were identified in 2/143 (1.4%) of samples tested. None of the Enterobacteriaceae isolates were resistant to meropenem or colistin. Similarly, all Enterococcus isolates remained susceptible to ampicillin, penicillin and vancomycin. Finding multi-drug resistant bacteria which are frequently isolated from human infections is concerning, although the contribution of the global food trade to the dissemination of resistance remains cryptic. These results suggest that imported plant-based foods may be an underappreciated source of clinically relevant resistant organisms. Further study is required to address these gaps in our understanding of the epidemiology of resistance, and the magnitude of the risk posed to human health by these organisms.


Assuntos
Enterobacteriaceae/isolamento & purificação , Enterococcus/isolamento & purificação , Staphylococcus aureus Resistente à Meticilina/isolamento & purificação , Plantas Comestíveis/microbiologia , Antibacterianos/farmacologia , Canadá , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterococcus/efeitos dos fármacos , Enterococcus/genética , Frutas/microbiologia , Humanos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , Quinolonas/farmacologia , Especiarias/microbiologia , Verduras/microbiologia , beta-Lactamases/genética
17.
J Infect Public Health ; 13(1): 125-130, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31353310

RESUMO

BACKGROUND: Natural products derived from marine microbes have more potential toward to treatment of various diseases. Among the microbes, the secondary metabolites recovered from the marine actinomycetes were more added values. OBJECTIVE: A promising antimicrobial metabolite producing filamentous actinomycete SCA-7 recovered from Alkhobar marine region was investigated for its potential to inhibit Gram positive Enterococcus sp. In addition to the chemical characterization, the polyketide gene cluster of the actinomycete SCA-7 was sequenced. RESULTS: Among the 8 actinomycetes isolated from the marine sample, the isolate SCA-7 produced significant antimicrobial activity against Enterococcus sp. The biochemical, physiological and morphological characteristics and fermentation assimilation pattern confirmed that the isolate belonged to the genus Streptomyces. The 16S rRNA gene amplification and sequencing results showed 99% sequence similarity to Streptomyces felleus. The antimicrobial activity of the crude ethyl acetate extract was performed by disc diffusion method. The spectral characterization was done by 13C NMR and 1H NMR. The compound was polyketide in nature. The Minimum Inhibitory Concentration (MIC) of the polyketide compound against Enterococcus sp. was 25µg/mL. Among the agro-industrial waste materials, wheat bran showed increased secondary metabolite production. Antibacterial activity was found to be high when the isolate SCA-7 was grown in wheat bran substrate and maximum zone of inhibition (22mm) was recorded in it. Among the carbon and nitrogen sources, lactose enhanced the production of secondary metabolites and the zone of inhibition against Enterococcus sp. was 25mm. The amplification and sequencing of the ketoacyl synthase gene clearly indicated that it was type I polyketide synthase (PKS) gene of Streptomyces species. CONCLUSION: Overall, the therapeutic drug molecule isolated from the marine Streptomyces species might be used for the treatment of disease causing microbial clinical pathogen.


Assuntos
Policetídeos/farmacologia , Streptomyces/química , Streptomyces/isolamento & purificação , Antibacterianos/isolamento & purificação , Antibacterianos/farmacologia , Carbono/metabolismo , Enterococcus/efeitos dos fármacos , Sedimentos Geológicos/microbiologia , Testes de Sensibilidade Microbiana , Família Multigênica , Filogenia , Policetídeos/isolamento & purificação , RNA Ribossômico 16S/genética , Metabolismo Secundário , Streptomyces/genética
18.
Folia Microbiol (Praha) ; 65(1): 79-85, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31041600

RESUMO

In Slovakia, dairy products made from ewes' milk have a long tradition. These products include the lactic acid product called "zincica" which is a by-product occurring during the preparation of ewes' lump cheese. There is no information in the literature regarding the special properties of the microbiota, especially lactic acid Firmicutes, which can survive in "zincica." From the safety aspect, enterococci are a controversial group of bacteria, and those from "zincica" have never been tested for their properties. The "zincica" used in our study was supplied by several different agrofarms producing ewes' lump cheese in central Slovakia. The species Enterococcus faecium (strains EF30E1, EF32E1, EF34E1, EF34E5) and Enterococcus faecalis (strains EE30E4, EE35E1, E31E2, altogether 7) were detected in samples from "zincica" identified using MALDI-TOF spectrometry with secure genus identification/probable species identification and then confirmed by means of PCR. Enterococci were hemolysis-negative and the genes of the typical enterococcal virulence factors were mostly absent; the gelE gene was found in two E. faecium strains (EF30E1 and EF32E1), the agg gene was detected in E. faecalis EE35E1, and the esp gene was found in two E. faecalis strains (EE30E4 and EE31E2). No strains harbored the cytolysin A gene. Biofilm formation was detected in four strains (EF30E1, EF32E1, EF34E1, and EF34E5), indicating highly positive and low-grade positive biofilm formation. Enterococci were mostly susceptible to antibiotics tested for their phenotype. This is the first study to analyze enterococci in "zincica."


Assuntos
Queijo/microbiologia , Enterococcus/classificação , Microbiologia de Alimentos , Inocuidade dos Alimentos , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Biofilmes/crescimento & desenvolvimento , Enterococcus/efeitos dos fármacos , Enterococcus/patogenicidade , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/genética , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Feminino , Testes de Sensibilidade Microbiana , Microbiota , Ovinos , Eslováquia , Fatores de Virulência/genética
19.
Microb Ecol ; 80(1): 1-13, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31838570

RESUMO

Antimicrobial resistance (AMR) in the aquatic environment has received increasing attention in recent years, and growing eutrophication problems may contribute to AMR in aquatic ecosystems. To evaluate whether and how eutrophication affects AMR, 40 surface water samples were collected from the Minjiang River, Fujian Province, China. Total nitrogen (TN), total phosphorus (TP), and chemical oxygen demand (CODMn) were measured as eutrophication factors. Additionally, enterococci species were isolated and their resistance to six common antibiotics was tested. Eutrophication generally showed a trend of increasing with the flow direction of the Minjiang River, with 25 sites (62.5%) having a TN/TP value over the Redfield value (16:1), which indicated that eutrophication in this region was of phosphorus limitation. High nutrition sites were in or near urban areas. Poor quality water was found in the middle and lower reaches of the Minjiang River system. The resistance frequency of 40 enterococci isolates to the six antibiotics tested was as follows: oxytetracycline > erythromycin > ciprofloxacin > chloramphenicol > ampicillin > vancomycin (70, 50, 17.5, 12.5, 2.5, 0%), and the multi-resistant rate reached 50% with eight resistance phenotypes. AMR also increased along the direction of water flow downstream, and most of the sites with the highest AMR were in or near urban areas, as was true for nutrition levels. Positive correlations between AMR and eutrophication factors (TN, TP, and CODMn) were identified using the Pearson's correlation coefficient, and TN/TP generally was negatively related to AMR. These results indicated that eutrophication may induce or selective for resistance of water-borne pathogens to antibiotics, with a high resistance level and a wide resistance spectrum.


Assuntos
Resistência Microbiana a Medicamentos , Enterococcus/efeitos dos fármacos , Eutrofização , Rios/microbiologia , Análise da Demanda Biológica de Oxigênio , China , Enterococcus/isolamento & purificação , Enterococcus/fisiologia , Nitrogênio/análise , Fósforo/análise , Rios/química
20.
J Appl Microbiol ; 128(4): 1221-1233, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31834656

RESUMO

AIM: It is well-known that enterococci are abundant in the environment; however, the role of surface water as a reservoir of antimicrobial-resistant enterococci remains largely undefined. In this study, surface water samples were collected over a 2-year period from the Upper Oconee watershed, Athens, GA to examine enterococci and their antimicrobial resistance. METHODS AND RESULTS: Approximately 97% (445/458) of the samples were positive for enterococci and a total of 637 enterococci were isolated. The predominant species were Enterococcus casseliflavus (33·6%) followed by Enterococcus faecalis (26·5%) and Enterococcus hirae (13·2%). Regardless of species, the highest levels of resistance were to lincomycin (88·5%) and tetracycline (13%); isolates also exhibited resistance to newer antimicrobials, daptomycin (8·9%) and tigecycline (6·4%). Multidrug resistance (resistance ≥3 antimicrobial classes) was observed to as many as five classes of antimicrobials. Resistant enterococci appeared to be randomly dispersed over the seasons rather than clustered by species or antimicrobial resistance. CONCLUSIONS: This study demonstrated that surface waters contain a large population of diverse species of antimicrobial-resistant enterococci, including resistance to new antimicrobials. SIGNIFICANCE AND IMPACT OF THE STUDY: These results may indicate the potential of human intestinal illness and/or colonization of the human gut with resistant enterococci as enterococci correlate with increased disease risk to humans during recreational exposure to water.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Enterococcus/isolamento & purificação , Água Doce/microbiologia , Microbiologia da Água , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterococcus/classificação , Enterococcus/efeitos dos fármacos , Monitoramento Ambiental , Georgia , Humanos , Testes de Sensibilidade Microbiana
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