TCC - Bacharelado em Ciências Biológicas (Sede)
URI permanente para esta coleçãohttps://arandu.ufrpe.br/handle/123456789/412
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Resultados da Pesquisa
Item Caracterização molecular de determinantes de resistência a antibióticos de Salmonella spp. isoladas de carne de frango in natura comercializados em mercados públicos de Recife - PE(2020-02-03) Silva, Marcela Oliveira da; Souza, Paula Mariana Salgueiro de; http://lattes.cnpq.br/6281410502740086; http://lattes.cnpq.br/9549169192404311Salmonella is one of the main causative agents of foodborne infections. Salmonellosis becomes more dangerous when strains resistant to various antibiotics are found in food, especially in chickens, one of the main vehicles for transmitting this pathogen to humans. The aim of this study was to characterize the determinants of antibiotic resistance present in Salmonella spp. isolated from fresh chicken meat sold in public markets in the city of Recife. For that, 21 isolates of Salmonella spp. underwent phenotypic and molecular tests to assess susceptibility to antibiotics and to investigate determinants of resistance to [beta]-lactams and quinolones. The results obtained demonstrated the presence of three large clonal groups among bacterial isolates, in addition to the presence of genes encoding [beta]-lactamases and genes that confer resistance to quinolones. The spread of different polyclonal groups of Salmonella spp. MDR, in chicken carcasses, shown in this study, reinforces the need for effective controls to contain this microorganism, which in addition to being a risk to public health, is also responsible for considerable economic losses.Item Análise de mecanismos de resistência em bactérias clínicas oriundas de hospitais de Pernambuco(2021-02-17) Silva, Jonas de Melo Silvestre da; Almeida, Anna Carolina Soares; http://lattes.cnpq.br/4891800920829895; http://lattes.cnpq.br/9044602995334190The spread of resistant bacteria or superbugs has been considered a catastrophic threat to the health of the population and represents one of the main challenges in the area of health worldwide. This work's main objective is to identify genetic and molecular determinants, resistance mechanisms, and the clonal relationship between twenty-two isolates obtained from two hospitals in Pernambuco. Isolates of: Klebsiella pneumoniae, Klebsiella ozaenae, Escherichia coli, and Enterobacter spp were included, all of which showed a phenotypic profile of multidrug resistance (MDR). Isolates from the University Hospital of the Federal University of Vale do São Francisco had a higher resistance profile compared to isolates from the University Hospital Oswaldo Cruz located in Recife, mainly to aminoglycosides and 3rd and 4th generation cephalosporins. Using the polymerase chain reaction (PCR) technique, it was possible to detect at least one of the B-lactam resistance genes tested in all isolates, except for 2 isolates that did not present any of the genes evaluated. The blaCTX-M gene was the most prevalent found in this study. And despite half of the samples having a resistance profile to carbapenems, the blaKPC gene was the least detected. In addition, clonal relationship analysis using the REP-PCR technique revealed a possible endemicity of a single clonal type in the Intensive Care Unit at Hospital Universitário Oswaldo Cruz located in Recife. At the University Hospital of the Federal University of Vale do São Francisco, the establishment of two clonal groups that have been disseminated for at least 3 months was identified. The presence of multiresistant bacteria in hospital units reinforces the need for strategies to contain infections and spread these pathogens, especially in ICUs.Item Análise de mecanismos de resistência a polimixina em isolados de Klebsiella pneumoniae(2021-12-17) Andrade, Rauana Lins de; Almeida, Anna Carolina Soares; Santos, Bárbara Nazly Rodrigues; http://lattes.cnpq.br/4795529090461229; http://lattes.cnpq.br/4891800920829895; http://lattes.cnpq.br/8836137133949593Infections for Klebsiella pneumoniae Carbapenemase-producing have been a public health problem leading to increased patient morbidity and mortality, which has led to the reintroduction of a previously discontinued antimicrobial for human use, polymyxins. The raise in resistance to polymyxins has made treatment even more difficult, which is worrying due to the high worldwide dissemination of these strains.This study aimed to perform a genetic analysis of two-component systems involved in polymyxin resistance in Klebsiella pneumoniae isolates. Sixteen multiresistant K. pneumoniae isolates were studied. The clonal relationship was performed from the investigation of repeated extragenic palindromic sequences (REP). The genes of the two-component enzyme regulatory systems (pmrA, pmrB, phoP, phoQ) were amplified by polymerase chain reaction (PCR). The identification of mutations was performed by DNA sequencing with comparative analysis using the MGH 78578 strain as reference. It was possible to distinguish the presence of four groups with clonal relationship of the same species with a variation of 2 to 5 unshared bands, indicating a pattern of similarity between all bacteria in the study. All isolates had more than one mutation in the coding regions of the genes studied, the prevalence was of mutations classified as silent in pmrA and phoP. However, Frameshift Nonsense and Missense mutations were identified in pmrB and phoQ genes, which led to alterations in the amino acid chain and production of a non-functional protein. Nucleotide alterations in the coding regions of the TCS regulatory genes (phoPQ and pmrAB) and the compromise of the protein sequence are considered the most relevant mechanisms regarding the mediation of resistance to polymyxins.