Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 38
Filtrar
1.
Ann Pharm Fr ; 82(3): 545-552, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38218426

RESUMO

INTRODUCTION: The escalating bacterial resistance stands as an increasingly pertinent concern, particularly in the post-pandemic era where the use of antibiotics appears to be relentlessly surging, giving rise to profound apprehensions. The substantial utilization of last-generation penicillins and cephalosporins is anticipated to imminently result in the emergence of superbugs for which therapeutic solutions will be scarce. METHODS: An analysis of antibiotic consumption in the hospital setting has been conducted in an Italian healthcare organization. Querying the internal management system facilitated the calculation of indicators and assessment of prescription trends. RESULTS: A comparison has been made between the first half of 2023 and the first half of 2022, to highlight the exponential growth in the consumption of beta-lactam antibiotics, with consumption doubling compared to the previous year's semester. Overall, considering the prescription averages, there is a prescribing growth of +29% concerning hospitalization and +28% concerning hospital discharge. However, it should be noted that the consumption of certain antibiotics such as sulphonamides and trimethoprim (-103.00%), tetracyclines (-54.00%), macrolides, lincosamides and streptogramins (-50.00%) and colistin (-13.00%) decreased. CONCLUSION: This real-world evidence analysis aimed to support the justified and comprehensible global concerns regarding bacterial resistance. The extensive consumption of antibiotics will inevitably lead to the development of increasingly drug-resistant bacteria for which no antibiotic may be efficacious. National programs addressing antibiotic resistance and the awareness of all healthcare personnel must be accorded the utmost priority to enhance consumption data and, consequently, safeguard future human survival.


Assuntos
Antibacterianos , Infecções Bacterianas , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Penicilinas , Resistência Microbiana a Medicamentos , Infecções Bacterianas/tratamento farmacológico , Atenção à Saúde , Itália
2.
Ann Pharm Fr ; 81(4): 627-635, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36858285

RESUMO

BACKGROUND: The phenomenon of antibiotic resistance shows no sign of stopping, despite global policies to combat it that have been in place for several years. The risk of forms of pathogenic microorganisms that are increasingly resistant to common antibiotics has led health authorities around the world to pay greater attention to the phenomenon. The worrying situation, has led to further recommendations from the World Health Organization (WHO) and national recommendations in Italy through the new National Plan against Antibiotic Resistance 2022-2025 (PNCAR 2022-2025). AIM: This manuscript aims to raise the awareness of all health professionals to follow what is suggested by regulatory agencies and scientific societies. METHOD: We conducted a retrospective study of antibiotic pharmacoutilization in Italy, in the Campania region at the Azienda Sanitaria Locale (ASL) Napoli 3 Sud, on consumption in the first half of 2022 in a population of more than 1 million people. RESULT: The results indicate that consumption, based on defined daily doses (DDDs), is above the national average. Probably the COVID-19 pandemic has influenced this growth in prescriptions. CONCLUSIONS: Our study suggests an informed and appropriate use of antibiotics, so as to embark on a virtuous path in the fight against antibiotic resistance.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Estudos Retrospectivos , Pandemias , Antibacterianos/uso terapêutico , Itália/epidemiologia , Prescrições de Medicamentos
3.
Can J Microbiol ; 68(2): 139-145, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34662521

RESUMO

While monitoring the presence of antibiotic resistance in municipal wastewater bacteria from Mexico City, five Escherichia coli isolates were found to be resistant to carbapenems, antibiotics of "last resort" used mostly in hospitals. Further analysis revealed that these carbapenem-resistant isolates carried the gene encoding a metallo-beta-lactamase, NDM-5. The gene was found to be beared by a large, ∼145 kb conjugative plasmid, which also carries putative genes encoding resistance to sulfonamides, trimethoprim, tetracycline, ciprofloxacin, and chloramphenicol (although no phenotypic chloramphenicol resistance was detected) and quaternary-ammonium compounds. The plasmid also carried gene mobility determinants, such as integron integrase and two transposases. In addition to the direct public health threat posed by the presence of such multi-resistant organisms in wastewater released into the environment and used for crop irrigation; it is particularly concerning that carbapenem-resistant E. coli is rather rare in Mexican hospitals (<1%), but was found in small, 100 mL samples of municipal wastewater. This suggests that these organisms are under-reported by clinical microbiology laboratories, underlining the usefulness of wastewater monitoring, or that there is an unknown source of such carbapenem-resistant organisms that are being dumped into the wastewater. The source of these bacteria must be assessed and controlled to prevent further spread of this multi-resistance plasmid among other environmental and clinical microorganisms.


Assuntos
Escherichia coli/isolamento & purificação , Esgotos/microbiologia , beta-Lactamases , Antibacterianos/farmacologia , Escherichia coli/genética , Infecções por Escherichia coli , Humanos , México , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
4.
Can J Microbiol ; 67(12): 894-901, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34731576

RESUMO

This study investigated the effect of cefepime at sub-minimum inhibitory concentrations (sub-MICs) on in vitro biofilm formation (BF) by clinical isolates of Pseudomonas aeruginosa. The effect of cefepime at sub-MIC levels (½-1/256 MIC) on in vitro BF by six clinical isolates of P. aeruginosa was phenotypically assessed following 24 and 48 h of challenge using the tissue culture plate (TCP) assay. Quantitative real-time polymerase chain reaction (qRT-PCR) was employed to observe the change in expression of three biofilm-related genes, namely, a protease-encoding gene (lasA), fimbrial protein-encoding gene (cupA1), and alginate-encoding gene (algC), in a weak biofilm-producing strain of P. aeruginosa following 24 and 48 h of challenge with sub-MICs of cefepime. The BF morphology in response to cefepime was imaged using scanning electron microscopy (SEM). The TCP assay showed strain-, time-, and concentration-dependent changes in in vitro BF in P. aeruginosa following challenge with sub-MICs of cefepime, with a profound increase in strains with inherently no or weak biofilm-producing ability. RT-PCR revealed time-dependent upregulation in the expression of the investigated genes following challenge with ½ and » MIC levels, as confirmed by SEM. Cefepime at sub-MICs could upregulate the expression of BF-related genes and enhance BF by P. aeruginosa clinical isolates.


Assuntos
Infecções por Pseudomonas , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Biofilmes , Cefepima , Humanos , Testes de Sensibilidade Microbiana , Pseudomonas aeruginosa/genética
5.
Can J Microbiol ; : 1-10, 2021 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-34780296

RESUMO

Chromobacterium violaceum is an opportunistic pathogen found in tropical and subtropical regions worldwide. Chromobacterium violaceum infections are difficult to treat, and many strains are resistant to antibiotics. Recently, a novel plasmid (pChV1) was discovered in the type strain ATCC 12472, suggesting that other C. violaceum strains may harbor extra-chromosomal DNA. The aim of the present study was to detect and compare new plasmids in Brazilian strains of C. violaceum using next-generation sequencing techniques. We obtained draft genomes of six plasmids from strains isolated from the Amazon region and aligned them with pChV1. At least three plasmids, CVAC05, CVACO2, and CVT8, were similar to pChV1. Phylogenetic analysis suggested that these new extra-chromosomal DNA sequences have a common origin with pChV1 but have diverged. Many of the ORFs detected were related to plasmid segregation/maintenance, viral structural proteins, and proteins with unknown functions. These findings may enable better genetic manipulation of C. violaceum, which will enhance our ability to exploit this valuable microorganism in industrial and clinical applications.

6.
Can J Microbiol ; 67(7): 518-528, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33125853

RESUMO

Persisters are a form of dormancy in bacteria that provide temporary resistance to antibiotics. The following reports on the formation of Escherichia coli O157:H7 E318 type II persisters from a protracted (8 days) challenge with ampicillin. Escherichia coli O157:H7 followed a multiphasic die-off pattern with an initial rapid decline (Phase I) of susceptible cells that transitioned to a slower rate representing tolerant cells (Phase II). After 24 h post-antibiotic challenge, the E. coli O157:H7 levels remained relatively constant at 2 log CFU/mL (Phase III), but became non-culturable within 8-days (Phase IV). The revival of persisters in Phase III could be achieved by the removal of antibiotic stress, although those in Phase IV required an extended incubation period or application of acid-shock. The carbon utilization profile of persister cells was less diverse compared with non-persisters, with only methyl pyruvate being utilized from the range tested. Inclusion of methyl pyruvate in tryptic soy agar revived non-cultural persisters, presumably by stimulating metabolism. The results suggest that persisters could be subdivided into culturable or non-culturable cells, with the former representing a transition state to the latter. The study provided insights into how to revive cells from dormancy to aid enumeration and control.


Assuntos
Ácidos/farmacologia , Antibacterianos/farmacologia , Escherichia coli O157/efeitos dos fármacos , Escherichia coli O157/crescimento & desenvolvimento , Piruvatos/farmacologia , Contagem de Colônia Microbiana , Escherichia coli O157/genética
7.
Can J Microbiol ; 66(1): 46-58, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31622563

RESUMO

Microbial community composition in selected karst groundwater sites in the Yucatan Peninsula, Mexico, was assessed to determine the environmental variables influencing groundwater microbial diversity. The karst aquifer system is a groundwater-dependent ecosystem and is the world's second largest underwater karst cave system. The area's geology allows precipitation to infiltrate into the groundwater system and prevents accumulation of surface water; as such, groundwater is the only source of fresh water on the peninsula. The sampling locations consisted of three karst sinkholes that extend through the freshwater zone into the saline water, and an abandoned drinking water well of an ocean-side resort, during the dry and rainy seasons. The analysis showed that highly diverse microbial communities are present in the Yucatan groundwater, sustained by permanently warm temperatures and high nutrient input from human activity. Proximity to densely populated areas, such as tourist resorts, is the most important factor influencing both the diversity and presence of fecal bacteria and the antibiotic resistance profile.


Assuntos
Resistência Microbiana a Medicamentos , Água Subterrânea/microbiologia , Microbiota , Densidade Demográfica , Microbiologia da Água , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Resistência Microbiana a Medicamentos/genética , Fezes/microbiologia , Água Subterrânea/química , Humanos , México , Microbiota/genética , Nutrientes/análise , Estações do Ano
8.
Can J Microbiol ; 66(10): 549-561, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32330390

RESUMO

Agricultural practices such as manure applications could contribute to the spread of antibiotic resistance genes (ARGs) within the environment. Our objective was to assess the impact of certain fertilization methods (mineral or manure) and tillage practices (reduced or conventional) on the presence of ARGs and bacteria in soil and drainage water under wheat and grain corn crops. Targeted ARGs tet(T), sul1, and blaCTX-M-1 in liquid hog manure, soil, and water samples were quantified by qPCR. Conventional PCR was used to detect mcr-1 and mcr-2. ARGs in control plots were detected despite the absence of manure, representing an environmental reservoir of resistant microorganisms. The manure application rate higher than 39 m3/ha increased tet(T) and sul1 gene concentrations in soil for more than 180 days. Tillage practices had no impact on ARG concentrations in soil and water samples. The blaCTX-M-1 gene was only detected in seven water samples in 2016, but no link was established with the treatments. The mcr-1 and mcr-2 genes were not detected in all tested samples. This study demonstrated that tet(T) and sul1 gene concentrations increased in soil after liquid hog manure application as well as in drainage water in the next weeks.


Assuntos
Agricultura/métodos , Farmacorresistência Bacteriana/genética , Esterco/microbiologia , Microbiologia do Solo , Microbiologia da Água , Animais , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/genética , Genes Bacterianos , Suínos
9.
Can J Microbiol ; 65(4): 322-331, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30571145

RESUMO

To elucidate how widespread antibiotic resistance is in the surface water environment, we studied the prevalence of antibiotic resistance bacteria at four locations in southern Ontario. We found that the percentage of bacteria resistant to the antibiotic tetracycline was higher at the river site, which flows through agricultural land, and lower at the lake sites. A total of 225 colonies were selected for further testing of antibiotic disc susceptibility to eight different antibiotics to calculate the multiple antibiotic resistance (MAR) score and the antibiotic resistance index for each site. Although the isolates from the lake site outside the city displayed resistance to fewer antibiotics, their MAR scores were not significantly different from that of the lake sites adjacent to urban beaches, showing that MAR was widespread in the natural water environments tested. Isolation of colonies under selection pressure to tetracycline was found to have a significant effect on the likelihood that the isolates would contain multiple resistance traits for other antibiotics. Identification of isolates selected on tetracycline was compared with that of isolates that were sensitive to tetracycline, and the community composition was found to be distinctly different, although isolates from the genera Chryseobacterium, Pseudomonas, and Stenotrophomonas were found in both communities.


Assuntos
Bactérias/isolamento & purificação , Lagos/microbiologia , Rios/microbiologia , Resistência a Tetraciclina , Microbiologia da Água , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Ontário , Tetraciclina/farmacologia , Poluentes Químicos da Água/farmacologia
10.
Can J Microbiol ; 65(1): 34-44, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30248271

RESUMO

A global medical crisis is unfolding as antibiotics lose effectiveness against a growing number of bacterial pathogens. Horizontal gene transfer (HGT) contributes significantly to the rapid spread of resistance, yet the transmission dynamics of genes that confer antibiotic resistance are poorly understood. Multiple mechanisms of HGT liberate genes from normal vertical inheritance. Conjugation by plasmids, transduction by bacteriophages, and natural transformation by extracellular DNA each allow genetic material to jump between strains and species. Thus, HGT adds an important dimension to infectious disease whereby an antibiotic resistance gene (ARG) can be the agent of an outbreak by transferring resistance to multiple unrelated pathogens. Here, we review the small number of cases where HGT has been detected in clinical environments. We discuss differences and synergies between the spread of plasmid-borne and chromosomal ARGs, with a special consideration of the difficulties of detecting transduction and transformation by routine genetic diagnostics. We highlight how 11 of the top 12 priority antibiotic-resistant pathogens are known or predicted to be naturally transformable, raising the possibility that this mechanism of HGT makes significant contributions to the spread of ARGs. HGT drives the evolution of untreatable "superbugs" by concentrating ARGs together in the same cell, thus HGT must be included in strategies to prevent the emergence of resistant organisms in hospitals and other clinical settings.


Assuntos
Resistência Microbiana a Medicamentos/genética , Transferência Genética Horizontal , Conjugação Genética , Humanos , Plasmídeos , Transdução Genética , Transformação Genética
11.
Genome ; 61(7): 469-476, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29957088

RESUMO

A pigment-producing species of Serratia was isolated from the rhizosphere of a heavy metal resistant Cannabis sativa plant growing in effluent-affected soil of Hattar Industrial Estate, Haripur, Pakistan. Here, we report the genome sequence of this bacterium, which has been identified as Serratia nematodiphila on the basis of whole genome comparison using the OrthoANI classification scheme. The bacterium exhibited diverse traits, including plant growth promotion, antimicrobial, bioremediation, and pollutant tolerance capabilities including metal tolerance, azo dye degradation, ibuprofen degradation, etc. Plant growth-promoting exoenzyme production as well as phosphate solubilisation properties were observed. Genes for phosphate solubilisation, siderophore production, and chitin destruction were identified in addition to other industrially important enzymes like nitrilase and lipase. Secondary metabolite producing apparatus for high value chemicals in the whole genome was also analysed. The number of antibiotic resistance genes was then profiled in silico, through a match with Antibiotic Resistant Gene and CAR database. This is the first report of a S. nematodiphila genome from a polluted environment. This could significantly contribute to the understanding of pollution tolerance, antibiotic resistance, association with nematodes, production of bio-pesticide, and their role in plant growth promotion.


Assuntos
Cannabis/crescimento & desenvolvimento , Genoma Bacteriano/genética , Rizosfera , Serratia/genética , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biodegradação Ambiental , Cannabis/microbiologia , Interações Hospedeiro-Patógeno , Metais/metabolismo , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/microbiologia , Serratia/metabolismo , Serratia/fisiologia , Sequenciamento Completo do Genoma/métodos , Xenobióticos/metabolismo
12.
Can J Microbiol ; 64(3): 201-208, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29342372

RESUMO

The impact of amendment with swine manure compost (SMC), yard waste compost (YWC), or food waste compost (FWC) on the abundance of antibiotic resistance genes in soil was evaluated. Following a commercial-scale application of the composts in a field experiment, soils were sampled periodically for a decade, and archived air-dried. Soil DNA was extracted and gene targets quantified by qPCR. Compared with untreated control soil, all 3 amendment types increased the abundance of gene targets for up to 4 years postapplication. The abundance of several gene targets was much higher in soil amended with SMC than in soil receiving either YWC or FWC. The gene target ermB remained higher in the SMC treatment for a decade postapplication. Clostridia were significantly more abundant in the SMC-amended soil throughout the decade following application. Eight percent of Clostridium spp. isolates from the SMC treatment carried ermB. Overall, addition of organic amendments to soils has the potential to increase the abundance of antibiotic resistance genes. Amendments of fecal origin, such as SMC, will in addition entrain bacteria carrying antibiotic resistance genes. Environmentally recalcitrant clostridia, and the antibiotic resistance genes that they carry, will persist for many years under field conditions following the application of SMC.


Assuntos
Clostridium/genética , Resistência Microbiana a Medicamentos/genética , Microbiologia do Solo , Animais , Antibacterianos/farmacologia , Compostagem , Genes Bacterianos , Esterco/microbiologia , Tipagem Molecular , RNA Bacteriano/genética , RNA Ribossômico 16S/genética , Resíduos Sólidos , Sus scrofa
13.
Can J Microbiol ; 64(12): 915-924, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30114374

RESUMO

At the crossroad between Europe, Asia, and Africa, Bulgaria is part of the Mediterranean - Black Sea Flyway (MBSF) used by millions of migratory birds. In this study, bird species migrating through Bulgaria were investigated as carriers of zoonotic pathogens. In total, 706 birds belonging to 46 species were checked for the presence of various bacterial pathogens (Campylobacter, Yersinia, Salmonella, Listeria, Escherichia coli, Staphylococcus aureus, Francisella tularensis, Coxiella burnetii, Borrelia burgdorferi, and Brucella spp.). From 673 birds we investigated fecal samples, from the remaining 33, blood samples. We detected Campylobacter 16S rDNA gene in 1.3% of birds, but none were of pathogenic Campylobacter jejuni and Campylobacter coli species. Escherichia coli 16S rDNA gene was found in 8.8% of the birds. Out of 34 birds that transported Yersinia enterocolitica strains (5.05%), only 1 carried a pathogenic isolate. Three birds (0.4%) were carriers of nonpathogenic Salmonella strains. Four avian samples (0.6%) were positive for Listeria monocytogenes and 1 (0.15%) was positive for Brucella spp. None of the birds tested carried the tick-borne pathogens C. burnetii or B. burgdorferi sensu lato. Antibiotic-resistant strains were detected, suggesting that migratory birds could be reservoirs and spreaders of bacterial pathogens as well as antibiotic resistance genes.


Assuntos
Aves/microbiologia , Zoonoses/microbiologia , Migração Animal , Animais , Mar Negro , Reservatórios de Doenças , Farmacorresistência Bacteriana , Fezes/microbiologia
14.
Can J Microbiol ; 64(5): 293-304, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29562144

RESUMO

Plasmids are extrachromosomal DNA elements that can be found throughout bacteria, as well as in other domains of life. Nonetheless, the evolutionary processes underlying the persistence of plasmids are incompletely understood. Bacterial plasmids may encode genes for traits that are sometimes beneficial to their hosts, such as antimicrobial resistance, virulence, heavy metal tolerance, and the catabolism of unique nutrient sources. In the absence of selection for these traits, however, plasmids generally impose a fitness cost on their hosts. As such, plasmid persistence presents a conundrum: models predict that costly plasmids will be lost over time or that beneficial plasmid genes will be integrated into the host genome. However, laboratory and comparative studies have shown that plasmids can persist for long periods, even in the absence of positive selection. Several hypotheses have been proposed to explain plasmid persistence, including host-plasmid co-adaptation, plasmid hitchhiking, cross-ecotype transfer, and high plasmid transfer rates, but there is no clear evidence that any one model adequately resolves the plasmid paradox.


Assuntos
Bactérias/genética , Plasmídeos/genética , Adaptação Fisiológica , Evolução Molecular , Modelos Genéticos
15.
Trop Med Int Health ; 22(5): 567-575, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28187247

RESUMO

OBJECTIVE: To identify sociodemographic, knowledge and attitudinal correlates to antibiotic sharing among a community-based sample of adults (age 18 and older) in a low-income setting of the Philippines and to explore community-level data on informal antibiotic distribution in roadside stands (i.e., sari-sari stands). METHODS: Participants (n = 307) completed self-administered surveys. Correlates to antibiotic sharing were assessed using logistic regression with Firth's bias-adjusted estimates. Study staff also visited 106 roadside stands and collected data on availability and characteristics of antibiotics in the stands. RESULTS: 78% had shared antibiotics in their lifetime, most often with family members. In multivariable analysis, agreement with the belief that it is safe to prematurely stop an antibiotic course (OR: 2.8, CI: 1.3-5.8) and concerns about antibiotic side effects (OR: 2.1, CI: 1.1-4.4) were significantly associated with increased odds of reported antibiotic sharing. Antibiotic sharing was not associated with sociodemographic characteristics or antibiotic knowledge. Antibiotics were widely available in 60% of sampled sari-sari stands, in which 59% of antibiotics were missing expiration dates. Amoxicillin and cephalexin were the most commonly available antibiotics for sale at the stands (60% and 21%, respectively). CONCLUSIONS: Antibiotic sharing was common and was associated with misconceptions about proper antibiotic use. Antibiotics were widely available in sari-sari stands, and usually without expiration information. This study suggests that multipronged and locally tailored approaches to curbing informal antibiotic access are needed in the Philippines and similar Southeast-Asian countries.


Assuntos
Antibacterianos/uso terapêutico , Conhecimentos, Atitudes e Prática em Saúde , Conhecimento do Paciente sobre a Medicação , Medicamentos sob Prescrição/uso terapêutico , Características de Residência , Automedicação , Comportamento Social , Adulto , Amoxicilina , Cefalexina , Comércio , Prescrições de Medicamentos , Família , Feminino , Humanos , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Filipinas , Pobreza , Inquéritos e Questionários
16.
Can J Microbiol ; 63(5): 439-449, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28192677

RESUMO

The alga Cladophora glomerata can erupt in nuisance blooms throughout the lower Great Lakes. Since bacterial abundance increases with the emergence and decay of Cladophora, we investigated the prevalence of antibiotic resistance (ABR) in Cladophora-associated bacterial communities up-gradient and down-gradient from a large sewage treatment plant (STP) on Lake Ontario. Although STPs are well-known sources of ABR, we also expected detectable ABR from up-gradient wetland communities, since they receive surface run-off from urban and agricultural sources. Statistically significant differences in aquatic bacterial abundance and ABR were found between down-gradient beach samples and up-gradient coastal wetland samples (ANOVA, Holm-Sidak test, p < 0.05). Decaying and free-floating Cladophora sampled near the STP had the highest bacterial densities overall, including on ampicillin- and vancomycin-treated plates. However, quantitative polymerase chain reaction analysis of the ABR genes ampC, tetA, tetB, and vanA from environmental communities showed a different pattern. Some of the highest ABR gene levels occurred at the 2 coastal wetland sites (vanA). Overall, bacterial ABR profiles from environmental samples were distinguishable between living and decaying Cladophora, inferring that Cladophora may control bacterial ABR depending on its life-cycle stage. Our results also show how spatially and temporally dynamic ABR is in nearshore aquatic bacteria, which warrants further research.


Assuntos
Bactérias/efeitos dos fármacos , Clorófitas/microbiologia , Resistência Microbiana a Medicamentos/genética , Bactérias/crescimento & desenvolvimento , Genes Bacterianos , Lagos , Ontário , Microbiologia da Água
17.
Can J Microbiol ; 62(3): 233-40, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26854365

RESUMO

We investigated a collection of Pseudomonas aeruginosa strains from hospitalised patients (n = 20) and various environmental sources (n = 214) for their genetic relatedness; virulence properties; antibiotic resistance; and interaction with intestinal (Caco-2), renal (A-498), and lung (Calu-3) cell lines. Using RAPD-PCR, we found high diversity among the strains irrespective of their sources, with only 6 common (C) types containing strains from both a clinical and environmental source. Environmental strains belonging to these C-types showed greater adhesion to A-498 cells than did clinical strains (17 ± 13 bacteria/cell versus 13 ± 11 bacteria/cell; p < 0.001), whereas clinical strains showed significantly greater adhesion to Calu-3 and Caco-2 cells than did environmental strains (p < 0.001 for both). The virulence genes and antibiotic resistance profiles of the strains were similar; however, the prevalence of environmental strains carrying both exoS and exoU was significantly (p < 0.0368) higher than clinical strains. While all strains were resistant to ticarcillin and ticarcillin-clavulanic acid, resistance against aztreonam, gentamicin, amikacin, piperacillin, and ceftazidime varied among environmental and clinical strains. These results suggest that environmental strains of P. aeruginosa carry virulence properties similar to clinical strains, including adhesion to various human cell lines, with some strains showing a higher adhesion to specific cell lines, indicating they may have a better ability to cause infection in those sites under predisposing conditions of the host.


Assuntos
Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Células CACO-2 , Ácidos Clavulânicos/farmacologia , Resistência Microbiana a Medicamentos/efeitos dos fármacos , Microbiologia Ambiental , Humanos , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/patogenicidade , Técnica de Amplificação ao Acaso de DNA Polimórfico , Ticarcilina/farmacologia , Virulência/efeitos dos fármacos
18.
Can J Microbiol ; 62(7): 600-7, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27277701

RESUMO

Sewage sludge recovered from wastewater treatment plants contains antibiotic residues and is rich in antibiotic resistance genes, selected for and enriched in the digestive tracts of human using antibiotics. The use of sewage sludge as a crop fertilizer constitutes a potential route of human exposure to antibiotic resistance genes through consumption of contaminated crops. Several gene targets associated with antibiotic resistance (catA1, catB3, ereA, ereB, erm(B), str(A), str(B), qnrD, sul1, and mphA), mobile genetic elements (int1, mobA, IncW repA, IncP1 groups -α, -ß, -δ, -γ, -ε), and bacterial 16S rRNA (rrnS) were quantified by qPCR from soil and vegetable samples obtained from unamended and sludge-amended plots at an experimental field in London, Ontario. The qPCR data reveals an increase in abundance of gene targets in the soil and vegetables samples, indicating that there is potential for additional crop exposure to antibiotic resistance genes carried within sewage sludge following field application. It is therefore advisable to allow an appropriate delay period before harvesting of vegetables for human consumption.


Assuntos
Produtos Agrícolas , Resistência Microbiana a Medicamentos/genética , Fertilizantes , Plasmídeos/genética , Esgotos , Verduras , Antibacterianos/farmacologia , Humanos , Ontário , RNA Ribossômico 16S , Esgotos/microbiologia , Solo/química , Microbiologia do Solo , Verduras/microbiologia , Águas Residuárias
19.
Trop Med Int Health ; 20(11): 1559-1563, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26224321

RESUMO

OBJECTIVES: To determine antibiotic susceptibility of colonising pneumococcal serotypes in HIV-exposed infants before the introduction of the 13-valent pneumococcal conjugate vaccine (PCV13), because HIV-exposed infants are at increased risk of invasive pneumococcal infections. METHODS: Antibiotic susceptibility of 104 pneumococcal isolates, cultured from the nasopharynx from Tanzanian HIV-exposed infants, was determined using the disc diffusion method and the E-test according to EUCAST version 4.0 (2014) criteria. RESULTS: A total of 69.2% of isolates were intermediately susceptible for benzyl penicillin (MIC 0.06-2 mg/l ); no high-level resistance was found. All isolates but one were susceptible to ampicillin. Regarding non-beta-lactam antibiotics, 19.2% of isolates were resistant to doxycycline, 3.8% to erythromycin and 97.1% to trimethoprim/sulfamethoxazole. A total of 15.4% of isolates were resistant to three antibiotic classes or more. There were no differences in antibiotic susceptibility between vaccine and non-vaccine serotypes. Reduced susceptibility of colonising pneumococcal isolates for commonly used antibiotics is common in HIV-exposed Tanzanian infants. CONCLUSIONS: High-dose penicillin and ampicillin remain appropriate first choices for non-meningeal pneumococcal infections in this group.

20.
Trop Med Int Health ; 20(10): 1281-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25963224

RESUMO

OBJECTIVE: Published literature from resource-limited settings is infrequent, although urinary tract infections (UTI) are a common cause of outpatient presentation and antibiotic use. Point-of-care test (POCT) interpretation relates to antibiotic use and antibiotic resistance. We aimed to assess the diagnostic accuracy of POCT and their role in UTI antibiotic stewardship. METHODS: One-year retrospective analysis in three clinics on the Thailand-Myanmar border of non-pregnant adults presenting with urinary symptoms. POCT (urine dipstick and microscopy) were compared to culture with significant growth classified as pure growth of a single organism >10(5)  CFU/ml. RESULTS: In 247 patients, 82.6% female, the most common symptoms were dysuria (81.2%), suprapubic pain (67.8%) and urinary frequency (53.7%). After excluding contaminated samples, UTI was diagnosed in 52.4% (97/185); 71.1% (69/97) had a significant growth on culture, and >80% of these were Escherichia coli (20.9% produced extended-spectrum ß-lactamase (ESBL)). Positive urine dipstick (leucocyte esterase ≥1 and/or nitrate positive) compared against positive microscopy (white blood cell >10/HPF, bacteria ≥1/HPF, epithelial cells <5/HPF) had a higher sensitivity (99% vs. 57%) but a lower specificity (47% vs. 89%), respectively. Combined POCT resulted in the best sensitivity (98%) and specificity (81%). Nearly one in ten patients received an antimicrobial to which the organism was not fully sensitive. CONCLUSION: One rapid, cost-effective POCT was too inaccurate to be used alone by healthcare workers, impeding antibiotic stewardship in a high ESBL setting. Appropriate prescribing is improved with concurrent use and concordant results of urine dipstick and microscopy.


Assuntos
Infecções Urinárias/diagnóstico , Adolescente , Adulto , Idoso , Antibacterianos/uso terapêutico , Escherichia coli/isolamento & purificação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Tailândia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/urina , Adulto Jovem , beta-Lactamases/isolamento & purificação
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA