Mercury is widely used in industrial and extractive processes, and the improper disposal of waste or products containing this metal produces a significant impact on ecosystems, causing adverse effects on living organisms, including humans. Exposure to methylmercury, a highly toxic organic compound, causes important neurological and developmental impairments. Recently, the genotoxicity of mercurial compounds has gained prominence as one of the possible mechanisms associated with the neurological effects of mercury, mostly by disturbing the mitotic spindle and causing chromosome loss. In this sense, it is important to investigate if these compounds can also cause direct damage to DNA, such as single and double‐strand breaks. Thus, the aim of this study was to investigate the cytotoxic and genotoxic potential of methylmercury in cell lines derived from neurons (B103) and glia (C6), exposed to methylmercury (MeHg) for 24 h, by analyzing cell viability, metabolic activity, and damage to DNA and chromosomes. We found that in comparison to the neuronal cell line, glial cells showed higher tolerance to MeHg, and therefore a higher LC50 and consequent higher intracellular accumulation of Hg, which led to the occurrence of several genotoxic effects, as evidenced by the presence of micronuclei, bridges, sprouts, and chromosomal aberrations.

The establishment of cell lines from fish species is becoming important because of the increase in interest of these cells for viral analysis, environmental monitoring and cytogenetic studies. However, there is some discussion about the best conditions for maintaining these cells. We describe here a protocol for primary cell lines which we have found to be reliable. Fin biopsies from two species, Geophagus proximus and Astyanax bimaculatus, were isolated and cultured. We used three culture media (Leibovitz- L15, Dulbecco s Modified Eagle Medium- DMEM and 199) with or without the addition of AmnioMax and a standard temperature of 29C. The results showed that 199 medium was less efficient for both species. However, the cells of G. proximus had better proliferation in DMEM and L-15 media, while A. bimaculatus cells fared better in DMEM medium. The high concentration of L-glutamine and branched-chain amino acids (BCAAs) in the DMEM and L15 media was probably important for better adaptation of these cells. Furthermore, the addition of AmnioMax, a supplement rich in L-glutamine, increased cell proliferation in both species. Thus, the protocol initially established was tested in other tissues (fin, gills and kidney) of other fish species from the Amazon region. The cells were maintained in L-15 medium supplemented with 20% FBS (Fetal Bovine Serum) and 5% AmnioMax. It was observed that the cells were successfully subcultured and had a good proliferation, also the morphological characteristics were preserved. Thus, the methodology described in this research represents an innovative tool for the establishing of fish cell.

Introdução: Embora identificada a mais de 100 anos, a Doença de Chagas continua sem controle no Brasil, tanto em função do número instável de casos quanto pela carência de políticas públicas de enfrentamento efetivas. Em contexto recente o monitoramento dessa e de outras doenças tropicais negligenciadas pode ter perdido qualidade em função da chegada de novas doenças agudas no país e da decorrente sobrecarga de trabalho nos serviços de cuidado e atenção em saúde. Objetivo: avaliar o perfil epidemiológico da DCA através da comparação das séries históricas disponíveis no Sistema de Informação de Agravos de Notificação (SINAN), tabulados entre 2011 e 2020. Método: Foram utilizados dados públicos do Sistema de Informação de Agravos de Notificação coletados pelo Sistema Único de Saúde. Resultados: Aplicadas as técnicas quantitativas da epidemiologia descritiva, sugere-se que, nas áreas endêmicas e de alta vulnerabilidade para a Doença, a COVID-19 pode ter colaborado para o agravamento da subnotificação de Chagas, que apresentou redução próxima a 50% com relação à média dos anos anteriores. Conclusão: Admitindo que nesse momento a erradicação da Doença de Chagas e da COVID-19 não parecem próximas, o fortalecimento da Vigilância em Saúde é fator crítico de sucesso para a construção de cenários de saúde mais favoráveis.