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1.
J Med Microbiol ; 69(2): 228-232, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922949

RESUMO

Introduction. Rapid and reliable detection of carbapenemase-producing Enterobacterales (CPE) from surveillance cultures is critical in supporting a good infection control programme. We implemented a new algorithm for CPE detection incorporating the NG Test CARBA 5 in January 2019.Aim. Our goals were to compare turnaround time (TAT), costs and staff requirements between the old and new algorithm, and to evaluate the performance of the CARBA 5 test directly on colonies grown on CARBA Smart agar.Methodology. We analysed and compared the TAT of CPE surveillance cultures processed using the old and new CPE screening algorithm. The total actual reagent costs and staff requirements for the new CPE algorithm were compared with the estimated costs and staff requirements of the old CPE algorithm.Results. Of 197 isolates included in the evaluation of the new algorithm, 64 were positive for carbapenemases by both CARBA 5 and Xpert Carba-R assay. Of the 133 that were negative, two were found to harbour NDM and IMI genotypes. Significant improvements in TAT were achieved with 88.7 % of cultures with CPE, reported on the same day as growth was observed on CARBA Smart agar compared to none in the old algorithm. The new algorithm incurred lower costs and, based on our workload, the new algorithm is estimated to save 28.9 man-hours annually.Conclusion. CARBA 5 performs well on colonies growing on CARBA Smart agar and significant improvements in TAT can be achieved without incurring additional costs or staff requirements.


Assuntos
Proteínas de Bactérias/metabolismo , Técnicas de Laboratório Clínico/métodos , Contagem de Colônia Microbiana/métodos , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Ensaios Enzimáticos/métodos , Algoritmos , Proteínas de Bactérias/genética , Técnicas de Laboratório Clínico/economia , Contagem de Colônia Microbiana/economia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/diagnóstico , Ensaios Enzimáticos/economia , Humanos , Sensibilidade e Especificidade , beta-Lactamases/genética , beta-Lactamases/metabolismo
2.
Syst Appl Microbiol ; 43(2): 126052, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31932140

RESUMO

Acute oak decline (AOD) affects native UK oak species causing rapid decline and mortality in as little as five years. A major symptom of AOD is black weeping stem lesions associated with bacterial phytopathogens, Brenneria goodwinii and Gibbsiella quercinecans. However, there is limited knowledge on the ecological and environmental reservoirs of these phytopathogens. Rainwater and soils are common reservoirs of plant pathogens in a forest environment; therefore, the aim of this study was to investigate the survival of B. goodwinii and G. quercinecans in vitro when inoculated into rainwater and forest soil using a combination of agar-based colony counts and gyrB gene-targeted quantitative PCR (qPCR). Brenneria goodwinii lost viability on inoculation into soil and rainwater, but was detectable at low abundance in soil for 28 days using qPCR, suggesting a limited ability to persist outside of the host, potentially in a viable but non-culturable (VBNC) state. Conversely, Gibbsiella quercinecans, was re-isolated from rainwater for the entire duration of the experiment (84 days) and was re-isolated from forest soil after 28 days, with qPCR analysis corroborating these trends. These data demonstrate that B. goodwinii is unable to survive in forest soils and rainwater, suggesting that it may be an endosymbiont of oak trees, whereas G. quercinecans remains viable in soil and rainwater biomes, suggesting a broad ecological distribution. These data advance understanding of the potential epidemiology of AOD-associated bacteria and their ecological reservoirs, thus increasing the overall knowledge of the pathology of AOD, which assists the development of future management strategies.


Assuntos
Enterobacteriaceae/fisiologia , Florestas , Gammaproteobacteria/fisiologia , Doenças das Plantas/microbiologia , Quercus/microbiologia , Chuva/microbiologia , Microbiologia do Solo , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Gammaproteobacteria/crescimento & desenvolvimento , Gammaproteobacteria/isolamento & purificação , Viabilidade Microbiana , Especificidade da Espécie
3.
Food Microbiol ; 85: 103295, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31500701

RESUMO

Fermented red pepper (FRP) sauce has been eaten in worldwide for many years. The salt content and resident microbial community influences the quality of the FRP sauce and may confer health (e.g., probiotics) or harm (e.g., antibiotic resistance genes) to the consumers in some circumstances; however, the salt-mediated alteration of microbial community and antibiotic resistance genes are little known. In this study, a combination of whole genome sequencing and amplicon analysis was used to investigate the changes in microbial community and antimicrobial resistance genes in response to different salt content during red pepper fermentation. While the family Enterobacteriaceae dominated in high-salt (15-25%) samples, Lactobacillaceae quickly became the dominant population in place of Enterobacteriaceae after 24 days in 10% salt samples. Compared to 0.05 antibiotic resistance genes (ARGs) per cell number on average in 10% salt sample, 16.6 ARGs were present in high-salt samples, wherein the bacterial hosts were major assigned to Enterobacteriaceae including genera Enterobacter, Citrobacter, Escherichia, Salmonella and Klebsiella. Multidrug resistance genes were the predominant ARG type. Functional profiling showed that histidine kinase functions were of much higher abundance in high-salt samples and included several osmotic stress-related two-component systems that simultaneously encoded ARGs. These results give first metagenomic insights into the salt-mediated changes in microbial community composition and a broad view of associated antibiotic resistance genes in the process of food fermentation.


Assuntos
Capsicum/química , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/genética , Lactobacillaceae/genética , Metagenoma , Microbiota , Cloreto de Sódio/química , Enterobacteriaceae/crescimento & desenvolvimento , Fermentação , Genes Bacterianos , Lactobacillaceae/crescimento & desenvolvimento , Metagenômica , Pressão Osmótica
4.
PLoS Negl Trop Dis ; 13(12): e0007883, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31790395

RESUMO

BACKGROUND: Symbiotic bacteria are pervasive in mosquitoes and their presence can influence many host phenotypes that affect vectoral capacity. While it is evident that environmental and host genetic factors contribute in shaping the microbiome of mosquitoes, we have a poor understanding regarding how bacterial genetics affects colonization of the mosquito gut. The CRISPR/Cas9 gene editing system is a powerful tool to alter bacterial genomes facilitating investigations into host-microbe interactions but has yet to be applied to insect symbionts. METHODOLOGY/PRINCIPAL FINDINGS: To investigate the role of bacterial genetic factors in mosquito biology and in colonization of mosquitoes we used CRISPR/Cas9 gene editing system to mutate the outer membrane protein A (ompA) gene of a Cedecea neteri symbiont isolated from Aedes mosquitoes. The ompA mutant had an impaired ability to form biofilms and poorly infected Ae. aegypti when reared in a mono-association under gnotobiotic conditions. In adult mosquitoes, the mutant had a significantly reduced infection prevalence compared to the wild type or complement strains, while no differences in prevalence were seen in larvae, suggesting genetic factors are particularly important for adult gut colonization. We also used the CRISPR/Cas9 system to integrate genes (antibiotic resistance and fluorescent markers) into the symbionts genome and demonstrated that these genes were functional in vitro and in vivo. CONCLUSIONS/SIGNIFICANCE: Our results shed insights into the role of ompA gene in host-microbe interactions in Ae. aegypti and confirm that CRISPR/Cas9 gene editing can be employed for genetic manipulation of non-model gut microbes. The ability to use this technology for site-specific integration of genes into the symbiont will facilitate the development of paratransgenic control strategies to interfere with arboviral pathogens such Chikungunya, dengue, Zika and Yellow fever viruses transmitted by Aedes mosquitoes.


Assuntos
Aedes/microbiologia , Proteínas da Membrana Bacteriana Externa/genética , Biofilmes/crescimento & desenvolvimento , Enterobacteriaceae/genética , Trato Gastrointestinal/microbiologia , Deleção de Genes , Técnicas de Inativação de Genes , Animais , Proteína 9 Associada à CRISPR/metabolismo , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Enterobacteriaceae/crescimento & desenvolvimento , Simbiose
5.
PLoS Negl Trop Dis ; 13(11): e0007464, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31738754

RESUMO

Tsetse flies (Diptera: Glossinidae) house a taxonomically diverse microbiota that includes environmentally acquired bacteria, maternally transmitted symbiotic bacteria, and pathogenic African trypanosomes. Sodalis glossinidius, which is a facultative symbiont that resides intra and extracellularly within multiple tsetse tissues, has been implicated as a mediator of trypanosome infection establishment in the fly's gut. Tsetse's gut-associated population of Sodalis are subjected to marked temperature fluctuations each time their ectothermic fly host imbibes vertebrate blood. The molecular mechanisms that Sodalis employs to deal with this heat stress are unknown. In this study, we examined the thermal tolerance and heat shock response of Sodalis. When grown on BHI agar plates, the bacterium exhibited the most prolific growth at 25oC, and did not grow at temperatures above 30oC. Growth on BHI agar plates at 31°C was dependent on either the addition of blood to the agar or reduction in oxygen levels. Sodalis was viable in liquid cultures for 24 hours at 30oC, but began to die upon further exposure. The rate of death increased with increased temperature. Similarly, Sodalis was able to survive for 48 hours within tsetse flies housed at 30oC, while a higher temperature (37oC) was lethal. Sodalis' genome contains homologues of the heat shock chaperone protein-encoding genes dnaK, dnaJ, and grpE, and their expression was up-regulated in thermally stressed Sodalis, both in vitro and in vivo within tsetse fly midguts. Arrested growth of E. coli dnaK, dnaJ, or grpE mutants under thermal stress was reversed when the cells were transformed with a low copy plasmid that encoded the Sodalis homologues of these genes. The information contained in this study provides insight into how arthropod vector enteric commensals, many of which mediate their host's ability to transmit pathogens, mitigate heat shock associated with the ingestion of a blood meal.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/fisiologia , Estresse Fisiológico , Temperatura Ambiente , Moscas Tsé-Tsé/microbiologia , Animais , Bactérias , Proteínas de Bactérias/genética , Técnicas de Cultura de Células , Enterobacteriaceae/genética , Escherichia coli/genética , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/genética , Cinética , Simbiose , Termotolerância , Trypanosoma
6.
Environ Pollut ; 251: 910-920, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31234257

RESUMO

The toxic sensitivity in different physiological levels of chromium (Cr) contaminated soils with environmentally equivalent concentrations (EEC) was fully unknown. The earthworm Eisenia fetida was exposed to a Cr-contaminated soil at the EEC level (referred to as Cr-CS) to characterize the induced toxicity at the whole body, organ, tissue, subcellular structure and metabolic levels. The results showed that the survival rate, weight and biodiversity of the gut microorganisms (organ) had no significant difference (p > 0.05) between control and Cr-CS groups. Qualitative histopathological and subcellular evaluations from morphology showed earthworms obvious injuries. The organelle injuries combined with the metabolic changes provided additional evidence that the Cr-CS damaged the nucleus and probably disturbed the nucleic acid metabolism of earthworms. 2-hexyl-5-ethyl-3-furansulfonate, dimethylglycine, betaine and scyllo-inositol were sensitive and relatively quantitative metabolites that were recommended as potential biomarkers for Cr-CS based on their significant weights in the multivariate analysis model. In addition, the relative abundance of Burkholderiaceae, Enterobacteriaceae and Microscillaceae of the earthworm guts in the Cr-CS group significantly increased, particularly for Burkholderiaceae (increased by 13.1%), while that of Aeromonadaceae significantly decreased by 5.6% in contrast with the control group. These results provided new insights into our understanding of the toxic effects of the EEC level of Cr contaminated soil from different physiological levels of earthworms and extend our knowledge on the composition and sensitivity of the earthworm gut microbiota in Cr contaminated soil ecosystems. Furthermore, these toxic responses from gut microorganisms to metabolites of earthworms provided important data to improve the adverse outcome pathway and toxic mechanism of the Cr-CS if the earthworm genomics and proteomics would be also gained in the future.


Assuntos
Cromo/toxicidade , Poluição Ambiental/análise , Oligoquetos/metabolismo , Oligoquetos/microbiologia , Poluentes do Solo/toxicidade , Solo/química , Animais , Bacteroidetes/crescimento & desenvolvimento , Burkholderiaceae/crescimento & desenvolvimento , Cromo/análise , Enterobacteriaceae/crescimento & desenvolvimento , Organelas/efeitos dos fármacos , Poluentes do Solo/análise
7.
PLoS One ; 14(6): e0217468, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31170167

RESUMO

OBJECTIVES: To determine the influence of local spread of clonal strains and testing of follow-up isolates on categorical (CA) and essential agreement rates (EA) of common colistin (COL) drug susceptibility testing methods with the broth microdilution (BMD) reference method. METHODS: COL MICs were determined for 178 bacterial isolates (Enterobacteriaceae, n = 97; Pseudomonas aeruginosa, n = 81) collected within one year from 64 patients by BMD according to ISO standard 20776-1 (reference method), the SensiTest BMD panel (ST), agar dilution (AD), the VITEK 2 instrument, and gradient diffusion (GD) using antibiotic strips of two and Muller-Hinton agar plates of three manufacturers. CA and EA with BMD were calculated for all isolates and compared to the subset of 68 unique isolates. RESULTS: CA ranges were 79.4% to 94.1% for the unique isolateq panel and 89.9% to 96.1% for all tested isolates. EA ranges were 64.7% to 86.8% and 67.4% to 91.0%, respectively. In both panels, EA for all GD assays was lower than 90%. Both lower and higher EA values ranging from-18.3% (MTS on BD agar) to + 6.3% (AD, Vitek 2) were observed in the full one-year sample. Acquisition of colistin resistance under therapy was observed for 3 patients. CONCLUSIONS: i) Repeat testing and local spread of clonal strains can positively or negatively affect CA and EA, ii) CA is more robust towards local influences than EA, iii) EA of GD and AD methods for COL with the reference BMD method is insufficient.


Assuntos
Colistina/farmacologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae , Infecções por Pseudomonas/epidemiologia , Pseudomonas aeruginosa , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/crescimento & desenvolvimento , Pseudomonas aeruginosa/isolamento & purificação
8.
EBioMedicine ; 43: 333-337, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31072770

RESUMO

BACKGROUND: Urinary tract infections are known to be caused by bacteria, but the potential implications of archaea have never been studied in this context. METHODS: In two different university hospital centres we used specific laboratory methods for the detection and culture of archaeal methanogens in 383 urine specimens prospectively collected for diagnosing urinary tract infection (UTI). FINDINGS: Methanobrevibacter smithii was detected by quantitative PCR and sequencing in 34 (9%) of the specimens collected from 34 patients. Escherichia coli, Klebsiella pneumoniae, Enterobacter sp., Enterococcus faecium and mixed cultures were detected along with M. smithii in eighteen, six, three, one and six urine samples, respectively. Interestingly, using our specific culture method for methanogens, we also isolated M. smithii in 31 (91%) of the 34 PCR positive urine samples. Genotyping the 31 isolates using multispacer sequence typing revealed three different genotypes which have been previously reported in intestinal microbiota. Antibiotic susceptibility testing found the 31 isolates to be in vitro susceptible to metronidazole (MIC: 1 mg/L) but resistant to fosfomycin, sulfamethoxazole-trimethoprim, amoxicillin-clavulanate and ofloxacin, commonly used to treat bacterial UTI. Finally, 19 (54%) of the 34 patients in whose urine samples M. smithii was detected were diagnosed with UTIs, including cystitis, pyelonephritis and prostatitis. INTERPRETATION: Our results show that M. smithii is part of the urinary microbiota of some individuals and could play a role in community-acquired UTI in association with enteric bacteria. FUND: This study was supported by IHU Méditerranée Infection, Marseille, France.


Assuntos
Técnicas Bacteriológicas , Técnicas de Cocultura , Enterobacteriaceae/crescimento & desenvolvimento , Methanobrevibacter/crescimento & desenvolvimento , Infecções Urinárias/diagnóstico , Infecções Urinárias/microbiologia , Adulto , Idoso , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Feminino , Humanos , Masculino , Methanobrevibacter/classificação , Methanobrevibacter/genética , Pessoa de Meia-Idade , Estudos Retrospectivos , Urinálise
9.
Sci Total Environ ; 672: 618-624, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30974353

RESUMO

Antimicrobial resistance is a major public health concern. Carbapenemase-producing Enterobacterales (CPE) represent a significant health threat as some strains are resistant to almost all available antibiotics. The aim of this research was to examine hospital effluent and municipal wastewater in an urban area in Ireland for CPE. Samples of hospital effluent (n = 5), municipal wastewater before (n = 5) and after (n = 4) the hospital effluent stream joined the municipal wastewater stream were collected over a nine-week period (May-June 2017). All samples were examined for CPE by direct plating onto Brilliance CRE agar. Isolates were selected for susceptibility testing to 15 antimicrobial agents in accordance with EUCAST criteria. Where relevant, isolates were tested for carbapenemase-encoding genes by real-time PCR. CPE were detected in five samples of hospital effluent, one sample of pre-hospital wastewater and three samples of post-hospital wastewater. Our findings suggest hospital effluent is a major contributor to CPE in municipal wastewater. Monitoring of hospital effluent for CPE could have important applications in detection and risk management of unrecognised dissemination of CPE in both the healthcare setting and the environment.


Assuntos
Proteínas de Bactérias/análise , Enterobacteriaceae/crescimento & desenvolvimento , Águas Residuárias/microbiologia , Microbiologia da Água , Poluentes da Água/metabolismo , beta-Lactamases/análise , Proteínas de Bactérias/metabolismo , Hospitais , Poluentes da Água/análise , beta-Lactamases/metabolismo
10.
PLoS One ; 14(4): e0215428, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30986251

RESUMO

OBJECTIVES: Large-scale clinical studies investigating associations between intestinal microbiota signatures and human diseases usually rely on stool samples. However, the timing of repeated stool sample collection cannot be predefined in longitudinal settings. Rectal swabs, being straightforward to obtain, have the potential to overcome this drawback. Therefore, we assessed the usability of rectal swabs for microbiome sampling in a cohort of hematological and oncological patients. STUDY DESIGN: We used a pipeline for intestinal microbiota analysis from deep rectal swabs which was established and validated with test samples and negative controls. Consecutively, a cohort of patients from hematology and oncology wards was established and weekly deep rectal swabs taken during their admissions and re-admissions. RESULTS: Validation of our newly developed pipeline for intestinal microbiota analysis from rectal swabs revealed consistent and reproducible results. Over a period of nine months, 418 rectal swabs were collected longitudinally from 41 patients. Adherence to the intended sampling protocol was 97%. After DNA extraction, sequencing, read pre-processing and filtering of chimeric sequences, 405 of 418 samples (96.9%) were eligible for further analyses. Follow-up samples and those taken under current antibiotic exposure showed a significant decrease in alpha diversity as compared to baseline samples. Microbial domination occurred most frequently by Enterococcaceae (99 samples, 24.4%) on family level and Enterococcus (90 samples, 22.2%) on genus level. Furthermore, we noticed a high abundance of potential skin commensals in 99 samples (24.4%). SUMMARY: Deep rectal swabs were shown to be reliable for microbiome sampling and analysis, with practical advantages related to high sampling adherence, easy timing, transport and storage. The relatively high abundance of putative skin commensals in this patient cohort may be of potential interest and should be further investigated. Generally, previous findings on alpha diversity dynamics obtained from stool samples were confirmed.


Assuntos
Enterobacteriaceae , Enterococcus , Fezes/microbiologia , Microbioma Gastrointestinal , Neoplasias Hematológicas/microbiologia , Manejo de Espécimes , Estudos de Coortes , Enterobacteriaceae/classificação , Enterobacteriaceae/crescimento & desenvolvimento , Enterococcus/classificação , Enterococcus/genética , Feminino , Humanos , Masculino
11.
J Appl Microbiol ; 126(6): 1910-1922, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30925006

RESUMO

AIMS: The aim was to determine the survival and persistence of Escherichia coli in soil amended with compost from different manure sources. METHOD AND RESULTS: Complex interactions of abiotic and biotic factors on E. coli survival were characterized in field experiment plots receiving randomly assigned compost treatments: dairy windrow, dairy vermicompost, poultry windrow or no compost. Biomass, activity and function of indigenous microbial communities in the composts and soils were measured concurrently to determine whether mechanisms of compost were driven by biotic or abiotic properties. E. coli persisted in compost containing poultry amendments but not in composts containing dairy or no amendments. Poultry compost contained more NH4 -N and a distinct microbial community compared to dairy and no compost treatments. A laboratory experiment performed on compost extracts suggested that E. coli survived better in extracts devoid of indigenous microbes as long as bioavailable nutrients were plentiful. CONCLUSIONS: Dairy-based composts are less likely to support E. coli survival than poultry-based composts. SIGNIFICANCE AND IMPACT OF THE STUDY: Results aid in risk assessment of the use of different types of manure-based compost and soil amendments in fruit and vegetable production by elucidating the roles of nutrient and microbial community composition on survival of E. coli in amended field soils.


Assuntos
Compostagem/métodos , Enterobacteriaceae/fisiologia , Esterco/microbiologia , Microbiologia do Solo , Spinacia oleracea/crescimento & desenvolvimento , Animais , Bovinos , Enterobacteriaceae/crescimento & desenvolvimento , Escherichia coli/crescimento & desenvolvimento , Escherichia coli/fisiologia , Viabilidade Microbiana , Nutrientes/química , Aves Domésticas , Solo/química
12.
Mol Microbiol ; 111(4): 1109-1125, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30710431

RESUMO

Contact-dependent growth inhibition (CDI) allows bacteria to recognize kin cells in mixed bacterial populations. In Escherichia coli, CDI mediated effector delivery has been shown to be species-specific, with a preference for the own strain over others. This specificity is achieved through an interaction between a receptor-binding domain in the CdiA protein and its cognate receptor protein on the target cell. But how conserved this specificity is has not previously been investigated in detail. Here, we show that class II CdiA receptor-binding domains and their Enterobacter cloacae analog are highly promiscuous, and can allow for efficient effector delivery into several different Enterobacteriaceae species, including Escherichia, Enterobacter, Klebsiella and Salmonella spp. In addition, although we observe a preference for the own receptors over others for two of the receptor-binding domains, this did not limit cross-species effector delivery in all experimental conditions. These results suggest that class II CdiA proteins could allow for broad-range and cross-species growth inhibition in mixed bacterial populations.


Assuntos
Toxinas Bacterianas/metabolismo , Inibição de Contato , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/metabolismo , Proteínas de Membrana/metabolismo , Toxinas Bacterianas/genética , Sítios de Ligação , Transporte Biológico , Enterobacteriaceae/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Proteínas de Membrana/genética , Ligação Proteica
13.
PLoS One ; 14(2): e0211888, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30735536

RESUMO

BACKGROUND: Empiric antibiotic therapy for suspected hematogenous vertebral osteomyelitis (HVO) should be initiated immediately in seriously ill patients and may be required in those with negative microbiological results. The aim of this study was to inform the appropriate selection of empiric antibiotic regimens for the treatment of suspected HVO by analyzing antimicrobial susceptibility of isolated bacteria from microbiologically proven HVO. METHOD: We conducted a retrospective chart review of adult patients with microbiologically proven HVO in five tertiary-care hospitals over a 7-year period. The appropriateness of empiric antibiotic regimens was assessed based on the antibiotic susceptibility profiles of isolated bacteria. RESULTS: In total, 358 cases of microbiologically proven HVO were identified. The main causative pathogens identified were methicillin-susceptible Staphylococcus aureus (33.5%), followed by methicillin-resistant S. aureus (MRSA) (24.9%), Enterobacteriaceae (19.3%), and Streptococcus species (11.7%). Extended spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae and anaerobes accounted for only 1.7% and 1.4%, respectively, of the causative pathogens. Overall, 73.5% of isolated pathogens were susceptible to levofloxacin plus rifampicin, 71.2% to levofloxacin plus clindamycin, and 64.5% to amoxicillin-clavulanate plus ciprofloxacin. The susceptibility to these oral combinations was lower in cases of healthcare-associated HVO (52.6%, 49.6%, and 37.6%, respectively) than in cases of community-acquired HVO (85.8%, 84.0%, and 80.4%, respectively). Vancomycin combined with ciprofloxacin, ceftriaxone, ceftazidime, or cefepime was similarly appropriate (susceptibility rates of 93.0%, 94.1%, 95.8%, and 95.8%, respectively). CONCLUSIONS: Based on our susceptibility data, vancomycin combined with a broad-spectrum cephalosporin or fluoroquinolone may be appropriate for empiric treatment of HVO. Fluoroquinolone-based oral combinations may be not appropriate due to frequent resistance to these agents, especially in cases of healthcare-associated HVO.


Assuntos
Antibacterianos/uso terapêutico , Infecções Bacterianas/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Osteomielite/tratamento farmacológico , Streptococcus/efeitos dos fármacos , Idoso , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Ciprofloxacino/uso terapêutico , Clindamicina/uso terapêutico , Quimioterapia Combinada , Pesquisa Empírica , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/patogenicidade , Feminino , Expressão Gênica , Humanos , Levofloxacino/uso terapêutico , Masculino , Staphylococcus aureus Resistente à Meticilina/crescimento & desenvolvimento , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Osteomielite/diagnóstico , Osteomielite/microbiologia , Osteomielite/patologia , Estudos Retrospectivos , Rifampina/uso terapêutico , Coluna Vertebral/efeitos dos fármacos , Coluna Vertebral/microbiologia , Coluna Vertebral/patologia , Streptococcus/crescimento & desenvolvimento , Streptococcus/patogenicidade , Vancomicina/uso terapêutico , beta-Lactamases/genética , beta-Lactamases/metabolismo
14.
PLoS One ; 14(1): e0208505, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30640915

RESUMO

A prospective cohort study (German Clinical Trial Registry, No. 00005273) was performed to determine pre-admission colonization rates, hospital acquisition risk factors, subsequent infection rates and colonization persistence including the respective molecular epidemiology and transmission rates of extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae (EPE). A total of 342 EPEs were isolated from rectal swabs of 1,334 patients on admission, at discharge and 6 months after hospitalization. Inclusion criteria were patients' age > 18 years, expected length of stays > 48 hours, external referral. The EPEs were characterized by routine microbiological methods, a DNA microarray and ERIC-PCR. EPE colonization was found in 12.7 % of admitted patients, with the highest rate (23.8 %) in patients from nursing homes. During hospitalization, 8.1 % of the patients were de novo EPE colonized, and invasive procedures, antibiotic and antacid therapies were independent risk factors. Only 1/169 patients colonized on admission developed a hospital-acquired EPE infection. Escherichia coli was the predominant EPE (88.9 %), and 92.1% of the ESBL phenotypes could be related to CTX-M variants with CTX-M-1/15 group being most frequent (88.9%). A corresponding ß-lactamase could not be identified in five isolates. Hospital-acquired EPE infections in patients colonized before or during hospitalization were rare. The diversity of the EPE strains was much higher than that of the underlying plasmids. In seven patients, transmission of the respective plasmid across different species could be observed indicating that the current strain-based surveillance approaches may underestimate the risk of inter-species transmission of resistance genes.


Assuntos
Farmacorresistência Bacteriana/genética , Genes Bacterianos , Hospitais , beta-Lactamases/biossíntese , Contagem de Colônia Microbiana , Enterobacteriaceae/genética , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/microbiologia , Seguimentos , Humanos , Epidemiologia Molecular , Admissão do Paciente , Alta do Paciente , Plasmídeos/genética , Fatores de Risco , beta-Lactamases/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-30633653

RESUMO

Decentralized wastewater management based on vertical flow constructed wetlands (VFCWs) can be an effective solution for minimizing sanitation problems also in urban landscapes, especially when considering rapidly expanding cities in developing countries. Yet, the mass implementation of VFCWs in urbanized areas first needs improvement of a few design drawbacks - among them, the control of infection hazard is of primary importance. Therefore, in this study, the possibility of mitigation of the VFCW-derived infection hazard was assessed, through analysis of bacteriostatic properties of top filtration layer materials, according to clinical experiences based on "safe" antimicrobial surfaces. The experiment was carried out on a daily operating VFCW. Coliform bacteria survival rates were measured for known VFCW construction materials such as Pinus bark, gravel, slag, charcoal and LECA. The calculated die-off rates expressed as 12-h first-order inactivation coefficients ranged between 6.91 h-1 (slag/summer) and 0.58 h-1 (Pinus bark/autumn). The obtained die-off curves showed charcoal, Pinus bark and LECA to have little bacteriostatic properties - even occasionally providing conditions promoting the growth of the coliform population. Meanwhile, slag and gravel were strictly inhibiting bacteria growth, reducing the population up to 99% within the first 3 h of contact time. The research showed that it is possible to significantly mitigate the infection hazard of VFCW by means of proper top-layer substrate material, similar or equal to slag or gravel.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Águas Residuárias , Purificação da Água/métodos , Áreas Alagadas , Carvão Vegetal/química , Argila/química , Contagem de Colônia Microbiana , Filtração , Viabilidade Microbiana , Casca de Planta/química , Estações do Ano , Águas Residuárias/química , Águas Residuárias/microbiologia
16.
Environ Sci Pollut Res Int ; 26(8): 7697-7710, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30666574

RESUMO

Surveys of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-pE) in stream water and untreated wastewater were carried out in Okinawa Prefecture, Japan. Thirty-six samples of water were collected from 18 streams in Okinawa Prefecture, as well as ten samples of wastewater flowing into four wastewater treatment plants (WWTPs). We investigated bacterial species, Escherichia coli O antigen, ESBL phenotype, ESBL genotype, and pulsed-field gel electrophoresis (PFGE) type of isolates, and total viable count and fecal coliforms as indicator organisms. The relation between indicator organisms and ESBL-pE was also validated using the same samples. A total of 141 ESBL-pE including 107 E. coli, 15 Klebsiella pneumoniae, 2 Proteus mirabilis, and 17 other species was isolated from stream water and wastewater. Of the 141 ESBL-pE, 14.9% and 54.6% were found to be blaCTX-M-15 and blaCTX-M-14-like types, respectively, which have been found in hospital isolates in Okinawa. Two pairs of possibly related patterns according to PFGE criteria were isolated from stream water and wastewater in two districts. When ESBL-pE was significantly isolated, total viable count and fecal coliform boundaries were ≥ 6.0 × 103 CFU/ml and ≥ 4.3 × 102 most probable number/100 ml, respectively. These results suggested that ESBL-pE isolated from stream water is human derived, and that total viable count and fecal coliforms will be useful as indicators for confirming the spread of ESBL-pE to the environment by means of simple hygiene surveys.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Monitoramento Ambiental/métodos , Microbiologia da Água , beta-Lactamases/análise , Eletroforese em Gel de Campo Pulsado , Escherichia coli , Humanos , Japão , Klebsiella pneumoniae , Reação em Cadeia da Polimerase , Proteus mirabilis , Inquéritos e Questionários , Águas Residuárias
17.
Cell Host Microbe ; 25(1): 128-139.e5, 2019 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-30629913

RESUMO

Neonates are highly susceptible to infection with enteric pathogens, but the underlying mechanisms are not resolved. We show that neonatal chick colonization with Salmonella enterica serovar Enteritidis requires a virulence-factor-dependent increase in epithelial oxygenation, which drives pathogen expansion by aerobic respiration. Co-infection experiments with an Escherichia coli strain carrying an oxygen-sensitive reporter suggest that S. Enteritidis competes with commensal Enterobacteriaceae for oxygen. A combination of Enterobacteriaceae and spore-forming bacteria, but not colonization with either community alone, confers colonization resistance against S. Enteritidis in neonatal chicks, phenocopying germ-free mice associated with adult chicken microbiota. Combining spore-forming bacteria with a probiotic E. coli isolate protects germ-free mice from pathogen colonization, but the protection is lost when the ability to respire oxygen under micro-aerophilic conditions is genetically ablated in E. coli. These results suggest that commensal Enterobacteriaceae contribute to colonization resistance by competing with S. Enteritidis for oxygen, a resource critical for pathogen expansion.


Assuntos
Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/fisiologia , Oxigênio/metabolismo , Salmonella/crescimento & desenvolvimento , Simbiose , Animais , Animais Recém-Nascidos , Ceco/microbiologia , Ceco/patologia , Galinhas , Coinfecção , Enterobacteriaceae/genética , Escherichia coli , Feminino , Microbioma Gastrointestinal , Masculino , Camundongos , Probióticos , Salmonella/genética , Salmonella/patogenicidade , Salmonelose Animal , Salmonella enteritidis/crescimento & desenvolvimento , Salmonella enteritidis/patogenicidade , Esporos Bacterianos/crescimento & desenvolvimento , Fatores de Virulência
18.
mBio ; 10(1)2019 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-30602581

RESUMO

The tsetse fly is the insect vector for the Trypanosoma brucei parasite, the causative agent of human African trypanosomiasis. The colonization and spread of the trypanosome correlate positively with the presence of a secondary symbiotic bacterium, Sodalis glossinidius The metabolic requirements and interactions of the bacterium with its host are poorly understood, and herein we describe a metabolic model of S. glossinidius metabolism. The model enabled the design and experimental verification of a defined medium that supports S. glossinidius growth ex vivo This has been used subsequently to analyze in vitro aspects of S. glossinidius metabolism, revealing multiple unique adaptations of the symbiont to its environment. Continued dependence on a sugar, and the importance of the chitin monomer N-acetyl-d-glucosamine as a carbon and energy source, suggests adaptation to host-derived molecules. Adaptation to the amino acid-rich blood diet is revealed by a strong dependence on l-glutamate as a source of carbon and nitrogen and by the ability to rescue a predicted l-arginine auxotrophy. Finally, the selective loss of thiamine biosynthesis, a vitamin provided to the host by the primary symbiont Wigglesworthia glossinidia, reveals an intersymbiont dependence. The reductive evolution of S. glossinidius to exploit environmentally derived metabolites has resulted in multiple weaknesses in the metabolic network. These weaknesses may become targets for reagents that inhibit S. glossinidius growth and aid the reduction of trypanosomal transmission.IMPORTANCE Human African trypanosomiasis is caused by the Trypanosoma brucei parasite. The tsetse fly vector is of interest for its potential to prevent disease spread, as it is essential for T. brucei life cycle progression and transmission. The tsetse's mutualistic endosymbiont Sodalis glossinidius has a link to trypanosome establishment, providing a disease control target. Here, we describe a new, experimentally verified model of S. glossinidius metabolism. This model has enabled the development of a defined growth medium that was used successfully to test aspects of S. glossinidius metabolism. We present S. glossinidius as uniquely adapted to life in the tsetse, through its reliance on the blood diet and host-derived sugars. Additionally, S. glossinidius has adapted to the tsetse's obligate symbiont Wigglesworthia glossinidia by scavenging a vitamin it produces for the insect. This work highlights the use of metabolic modeling to design defined growth media for symbiotic bacteria and may provide novel inhibitory targets to block trypanosome transmission.


Assuntos
Adaptação Fisiológica , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/metabolismo , Comportamento Alimentar , Simbiose , Moscas Tsé-Tsé/microbiologia , Moscas Tsé-Tsé/fisiologia , Animais , Carbono/metabolismo , Meios de Cultura/química , Vetores de Doenças , Metabolismo Energético , Glucose/metabolismo , Glutamatos/metabolismo , Nitrogênio/metabolismo , Tiamina/metabolismo
19.
J Sci Food Agric ; 99(1): 199-209, 2019 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-29851067

RESUMO

BACKGROUND: The quality of marinated ready-to-eat (RTE) swordfish fillets, with or without inoculation with the probiotic strain Lactobacillus paracasei IMPC 2.1, was assessed over 3 months of refrigerated storage at 4 °C. RTE probiotic and control fish fillets were sampled after 7, 14, 30, 60, and 90 days of storage. Microbiological tests were performed, and fatty acid (FA) profiles and malondialdehyde content were examined. Microbiological counts, including total viable count, lactic acid bacteria (LAB), yeasts, moulds, Enterobacteriaceae, and Pseudomonadaceae were determined. RESULTS: Inoculation successfully ensured the growth of the probiotic strain and prevented the growth of other LAB. The two RTE products showed significant differences in lipid profile and lipid oxidation during storage. In particular, inoculation with L. paracasei IMPC 2.1 increased the amount of polyunsaturated FAs and limited the amount of monounsaturated FAs and oleic acid, as well as lipid oxidation. It thus represents an interesting strategy for preserving the chemical quality of fish fillets and an alternative means of delivering probiotics. CONCLUSION: Probiotic inoculation with Lactobacillus paracasei seemed to delay lipid oxidation of the fish flesh and increase the retention of polyunsaturated FAs, suggesting a potential application for this strain in the seafood industry. © 2018 Society of Chemical Industry.


Assuntos
Fast Foods/microbiologia , Produtos Pesqueiros/análise , Produtos Pesqueiros/microbiologia , Peixes/microbiologia , Conservação de Alimentos/métodos , Lactobacillus paracasei/fisiologia , Animais , Antibiose , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/fisiologia , Fast Foods/análise , Armazenamento de Alimentos , Fungos/crescimento & desenvolvimento , Fungos/fisiologia , Lactobacillus paracasei/crescimento & desenvolvimento
20.
Meat Sci ; 147: 13-19, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30172085

RESUMO

The effect of pH and the spoilage of black wildebeest Longissimus thoracis et lumborum (LTL) muscles with normal (pH > 6.06) and high pH (DFD; pH < 6.06) was investigated for 12 days under refrigerated (5 ±â€¯1 °C) aerobic conditions. Results showed that pH affected colour, as initial values from Normal samples (L* = 33.08, a* = 13.60, b* = 10.29, C* = 17.10 and Hab = 36.85) were greater than values for DFD meat (L* = 27.21, a* = 11.10, b* = 6.97, C* = 13.12 and Hab = 32.08). Initial bacterial counts from DFD and Normal pH samples did not differ significantly. Over time, pH decreased for Normal and DFD samples until the 6th and 9th day, respectively, whilst both samples showed a significant decrease in redness and colour intensity. Aerobic bacteria and Enterobacteriaceae reached 7 log cfu/g > 4 days earlier than Normal pH samples and bacterial growth rate was >1.09-fold faster in DFD than Normal meat.


Assuntos
Cor , Carne/análise , Músculo Esquelético/química , Músculo Esquelético/microbiologia , Animais , Bactérias Aeróbias/crescimento & desenvolvimento , Bactérias Aeróbias/isolamento & purificação , Carga Bacteriana , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Armazenamento de Alimentos , Concentração de Íons de Hidrogênio , Carne/microbiologia , Refrigeração , Ruminantes
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