RESUMO
Antibiotics are considered emerging pollutants which indiscriminate use has led to the development of antibiotic-resistant bacteria, while their improper disposal has caused adverse effects to the environment and human health. Thus, the development of devices or techniques capable of detecting antibiotics with high sensitivity, low detection limits, and reasonable cost becomes of prime importance. In this work, an electronic tongue (e-tongue) based on molybdenum disulfide (MoS2) and graphene oxide (GO) was developed and employed to detect four distinct antibiotics, namely cloxacillin benzathine, erythromycin, streptomycin sulfate, and tetracycline hydrochloride. The five sensing units of the e-tongue were obtained using the drop-casting method to modify gold interdigitated electrodes with MoS2 and GO. Using Principal Component Analysis to process the experimental data allowed the e-tongue to recognize samples contaminated with distinct antibiotics at varied concentrations from 0.5 to 5.0 nmol L-1. Analyses with real samples were also performed using river water and human urine and the electronic tongue was able to differentiate the samples at a nanomolar level. The proposed system represents a sensitive and low-cost alternative for antibiotic analyses in different liquid media.
Assuntos
Antibacterianos/análise , Dissulfetos/química , Nariz Eletrônico , Grafite/química , Molibdênio/química , Cloxacilina/análise , Eletrodos , Eritromicina/análise , Ouro/química , Humanos , Estrutura Molecular , Estreptomicina/análise , Tetraciclina/análiseRESUMO
Environmental observations of antibiotics and other pharmaceuticals have received attention as indicators of an urbanizing global water cycle. When connections between environment and development of antibiotic resistance (ABR) are considered, it is increasingly important to understand the life cycle of antibiotics. Here we examined the global occurrence of erythromycin (ERY) in: 1. wastewater effluent, inland waters, drinking water, groundwater, and estuarine and coastal systems; 2. sewage sludge, biosolids and sediments; and 3. tissues of aquatic organisms. We then performed probabilistic environmental hazard assessments to identify probabilities of exceeding the predicted no-effect concentration (PNEC) of 1.0⯵gâ¯L-1 for promoting ABR, based on previous modeling of minimum inhibitory concentrations and minimal selective concentrations of ERY, and measured levels from different geographic regions. Marked differences were observed among geographic regions and matrices. For example, more information was available for water matrices (312 publications) than solids (97 publications). ERY has primarily been studied in Asia, North America and Europe with the majority of studies performed in China, USA, Spain and the United Kingdom. In surface waters 72.4% of the Asian studies have been performed in China, while 85.4% of the observations from North America were from the USA; Spain represented 41.9% of the European surface water studies. Remarkably, results from PEHAs indicated that the likelihood of exceeding the ERY PNEC for ABR in effluents was markedly high in Asia (33.3%) followed by Europe (20%) and North America (17.8%). Unfortunately, ERY occurrence data is comparatively limited in coastal and marine systems across large geographic regions including Southwest Asia, Eastern Europe, Africa, and Central and South America. Future studies are needed to understand risks of ERY and other antibiotics to human health and the environment, particularly in developing regions where waste management systems and treatment infrastructure are being implemented slower than access to and consumption of pharmaceuticals is occurring.
Assuntos
Resistência Microbiana a Medicamentos/genética , Monitoramento Ambiental , Poluentes Ambientais/análise , Poluição Ambiental/estatística & dados numéricos , Eritromicina/análise , Organismos Aquáticos , Água Subterrânea/química , Humanos , Esgotos/análise , Águas Residuárias/química , Ciclo Hidrológico , Poluentes Químicos da Água/análiseRESUMO
Group B Streptococcus (GBS) is the leading cause of neonatal infections. Our purpose was to characterize GBS colonization in pregnant women, current serotypes, resistance phenotypes and genes associated with virulence. In Misiones, Argentina, there are no previous data on this topic. Vaginal-rectal swabs from 3125 pregnant women were studied between 2004 and 2010. GBS strains were identified by conventional and serological methods (Phadebact Strep B Test, ETC International, Bactus AB, Sweden). Serotypes were detected using Strep-B Latex (Statens Serum Institut, Denmark). Resistance phenotypes were determined by the double-disk test. Genes were studied by PCR. Maternal colonization was 9.38%. Resistance to erythromycin was 11.6%, and the constitutive phenotype was the predominant one. Serotype Ia was the most frequent, whereas serotypes IV, VI, VII and VIII were not detected. The lmb, bca and hylB genes were detected in more than 79% of the strains. In this study, the colonization rate with GBS and the serotype distribution were compared with studies reported in other areas of the country. The high resistance to erythromycin in Misiones justifies performing antibiotic susceptibility testing. The serotype distribution, the genes encoding putative virulence factors, and the patterns of resistance phenotypes of GBS may vary in different areas. They thus need to be evaluated in each place to devise strategies for prevention.
Assuntos
Humanos , Feminino , Resistência Microbiana a Medicamentos , Eritromicina/análise , Eritromicina/isolamento & purificação , Técnicas In Vitro , Fenótipo , Gestantes , Infecções Estreptocócicas , Streptococcus agalactiae/genética , Streptococcus agalactiae/patogenicidade , Genótipo , Metodologia como Assunto , Sorotipagem , VirulênciaRESUMO
Antibiotics are used in apiculture to protect bees against a variety of brood diseases. As a result of the development of resistance to oxytetracycline, erythromycin and tylosin are increasingly used for the prevention and treatment of these diseases. Therefore, Brazilian authorities have added these antibiotics to the National Regulatory Monitoring Program for the control of residues in honey. An analytical method has been developed for the determination of residues of erythromycin and tylosin in honey. The procedure involves solid-phase extraction of diluted honey samples with Bond Elut cartridges, followed by LC/MS with electrospray positive ionization in the multiple reaction monitoring mode. Two characteristic transitions were monitored for both drugs. Average analyte recoveries of erythromycin and tylosin ranged from 99 to 109% from sets of replicate honey samples fortified with drug concentrations of 5, 10, 15, and 20 microg/kg. The method decision limits were determined to be 1.27 and 0.59 microg/kg for erythromycin and tylosin, respectively. The detection capabilities were 5 and 5.2 microg/kg for erythromycin and tylosin, respectively.
Assuntos
Antibacterianos/análise , Cromatografia Líquida de Alta Pressão/métodos , Resíduos de Drogas/análise , Eritromicina/análise , Contaminação de Alimentos/análise , Mel/análise , Espectrometria de Massas por Ionização por Electrospray/métodos , Tilosina/análiseRESUMO
Concentrations of erythromycin were measured in serum and tonsil from children who had received either the estolate or ethyl succinate suspension before surgery. The in vitro assay measured total erythromycin activity against a group A beta hemolytic streptococcus. Levels of erythromycin in serum and tonsil after single and multiple doses of the estolate were significantly higher than those after administration of the ethyl succinate. The therapeutic implications of these findings are unknown.