Banca de QUALIFICAÇÃO: LARA LUIZA FREITAS DE OLIVEIRA

Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.
STUDENT : LARA LUIZA FREITAS DE OLIVEIRA
DATE: 03/10/2022
TIME: 13:30
LOCAL: video conferencia
TITLE:

EVALUATION OF IN VITRO GENOTOXIC POTENTIAL AND INDUCTION OF ANTIMICROBIAL RESISTANCE BY EXPOSURE TO HEAVY METALS ASSOCIATED WITH MINING ACTIVITIES

KEY WORDS:

Heavy metals; Water contamination; Genotoxicity; Antibiotic resistance

PAGES: 75
BIG AREA: Ciências Biológicas
AREA: Morfologia
SUMMARY:

Ore tailings, such as those that reached the Doce River basin in 2015 with the Fundão dam failure, have a strong presence of heavy metals in their composition, elements considered toxic even in low concentrations. Among the harmful damages of these elements, the possibility of carcinogenesis is one of the most important, and in addition, the association between environmental contamination by heavy metals and antimicrobial resistance has been reported. The objective of this work was to evaluate the genotoxic and mutagenic effects in vitro, as well as the possible impact on the induction of antimicrobial resistance of exposure to the mixture of heavy metals in concentrations found in the Rio Doce basin after the disaster. Stock solutions were prepared from metal salts, and concentrations of iron (0.15 mg L^-1), manganese (0.06 mg L^-1) and cadmium (0.0002 mg L^-1) were reported in a previous study. The genotoxic and mutagenic potential of the metals will be analyzed by the comet assay and cytokinesis-blocked micronucleus test, respectively, using human colon adenocarcinoma cells (Caco-2). To evaluate the potential to induce resistance to antimicrobials (gentamicin, colistin, ciprofloxacin and meropenem) after exposure to heavy metals, a culture-based experiment for recovery of Escherichia coli bacteria from the intestinal microbiota of Astyanax lacustis fish was conducted. After exposure to metals, the animals would be euthanized at times zero, five and ten days and the entire intestine cultured in a growth broth with and without gentamicin pressure. After incubation, 100 µL of cultures at time zero were plated on nutrient, MacConkey and cetrimide agars, but only fungi recovered. The absence of bacteria may be related to intestinal dysbiosis in fish. A new experiment was proposed, to expose E. coli ATCC 25922 to the concentrations of metals found in loco and to analyze the susceptibility to antimicrobials by the broth microdilution method. It is expected to expand knowledge about the impact of exposure to concentrations of heavy metals individually and/or in mixtures on animal cells, as well as the possibility of inducing bacterial resistance to clinically relevant antimicrobials.

BANKING MEMBERS:
Presidente - 2875448 - RALPH GRUPPI THOME
Interno - 1680474 - FABIO VIEIRA DOS SANTOS
Externo ao Programa - 1716137 - HELIO BATISTA DOS SANTOS
Externa ao Programa - 1080217 - FARAH MARIA DRUMOND CHEQUER BALDONI