RESUMO
The disease coronavirus COVID-19 has been the cause of millions of deaths worldwide. Among the proteins of SARS-CoV-2, non-structural protein 12 (NSP12) plays a key role during COVID infection and is part of the RNA-dependent RNA polymerase complex. The monitoring of NSP12 polymorphisms is extremely important for the design of new antiviral drugs and monitoring of viral evolution. This study analyzed the NSP12 mutations detected in circulating SARS-CoV-2 during the years 2020 to 2022 in the population of the city of Manaus, Amazonas, Brazil. The most frequent mutations found were P323L and G671S. Reports in the literature indicate that these mutations are related to transmissibility efficiency, which may have contributed to the extremely high numbers of cases in this location. In addition, two mutations described here (E796D and R914K) are close and have RMSD that is similar to the mutations M794V and N911K, which have been described in the literature as influential on the performance of the NSP12 enzyme. These data demonstrate the need to monitor the emergence of new mutations in NSP12 in order to better understand their consequences for the treatments currently used and in the design of new drugs.
Assuntos
COVID-19 , RNA-Polimerase RNA-Dependente de Coronavírus , SARS-CoV-2 , Humanos , Brasil , Simulação por Computador , COVID-19/virologia , COVID-19/transmissão , Mutação/genética , SARS-CoV-2/genética , Proteínas não Estruturais Virais/genética , RNA-Polimerase RNA-Dependente de Coronavírus/genética , RNA-Polimerase RNA-Dependente de Coronavírus/metabolismoRESUMO
High case counts after the Gamma (P. 1) variant of severe acute respiratory syndrome coronavirus 2 emerged in Brazil raised concerns that previously infected persons might become reinfected. Investigation of a cluster of coronavirus disease cases in Parintins, in the Brazilian Amazon, suggested household transmission but did not identify high rates of reinfection.
Assuntos
COVID-19 , SARS-CoV-2 , Brasil/epidemiologia , Humanos , ReinfecçãoRESUMO
Leishmania nested PCR (LnPCR) targeted to the SSUrRNA gene and DNA sequencing were used to analyze 315 tissue samples from 80 Rattus norvegicus specimens trapped in an area endemic for leishmaniasis in Belo Horizonte, Minas Gerais, Brazil. Of the samples analyzed, 17.46% (55/315) of all tissues, 10% (8/80) of skin, 26.92% (21/78) of blood, 30.76% (24/78) of bone marrow and 2.53% (2/79) of spleen were positive for Leishmania. The overall infection prevalence was 36.25% (29/80) The DNA sequencing showed that 65.51% (19/29) of the positive animals were infected by parasites belonging to the Leishmania braziliensis complex. The identification of L. braziliensis DNA in R. norvegicus in an area with a high prevalence of leishmaniasis might imply a zoonotic role of this species. The rodent control programs and health education may represent important measures toward the control of leishmaniasis.