Bioprospecção para compostos antimicobacterianos

Tuberculosis represents a serious public health problem, with a high incidence rate, the emergence of multiresistant forms and difficult treatment. It is necessary to develop new compounds and plants are sources of these resources. The Brazilian savanna vegetation has a great biodiversity and holds the potential to contain specimens with some biological activity. The objective of this study was determined the antimycobacterial activity involving ten crude extracts of plants present in this biome: Plathymenia reticulata, Ouratea spectabilis, Galactia glaucescens, Apuleia molaris, Dipteryx alata, Brosimum gaudichaudii, Tabebuia caraíba, Pterodon Emarginatus, Terminalia fagifolia and Stachytarpheta sp. The results of the research demonstrated that the hydroalcoholic extracts of O. spectabilis and A. molaris had significant inhibitory concentrations for Mycobaterium tuberculosis and showed low toxicity against LLC-MK2 and Vero cells. The fractionation of these two samples revealed a hexanic fraction of A. molaris with significant pharmacological action against H37Rv, being characterized as having promising compounds for future trials involving antituberculosis activity.A tuberculose representa um sério problema de saúde pública, com alta taxa de incidência, surgimento de formas multirresistentes e difícil tratamento. Torna-se necessário o desenvolvimento de novos compostos e as plantas são fontes destes recursos. O cerrado é possuidor de uma grande biodiversidade e detém potencial em conter espécimes com alguma atividade biológica. Neste estudo objetivou-se a execução de ensaios laboratoriais, a fim de determinar a atividade antimicobacteriana envolvendo dez extratos brutos de plantas presentes neste bioma: Plathymenia reticulata, Ouratea spectabilis, Galactia glaucescens, Apuleia molaris, Dipteryx alata, Brosimum gaudichaudii, Tabebuia caraíba, Pterodon emarginatus, Terminalia fagifolia e Stachytarpheta sp. Os resultados da pesquisa demonstraram que os extratos hidroalcoólicos de O. spectabilis e A. molaris tiveram expressivas concentrações inibitórias para Mycobaterium tuberculosis e demonstraram baixa toxicidade frente as células LLC-MK2 e Vero. O fracionamento dessas duas amostras, relevou uma fração hexânica da A. molaris com significativa ação farmacológica frente a cepas H37Rv, sendo caracterizada como possuidora de compostos promissores para futuros ensaios envolvendo atividade antituberculose

Plants from the Brazilian Cerrado with antimycobacterial effect

Tuberculosis constitutes a serious public health problem because it has multi-resistant forms that require treatment that is both difficult and extensive. There is a need to develop new antimycobacterial compounds, and plants represent a source of therapeutic resources. This study analyzed antimycobacterial action in eight extracts from plants found in the Brazilian Cerrado. The results showed significant inhibitory concentrations in relation to Mycobacterium tuberculosis, especially from the extracts of Apuleia molaris and Ouratea spectabilis, both of which presented reduced cytotoxic effects. Fractionation revealed a hexane fraction of A. molaris with significant and promising activity regarding future in vivo assays

OBSERVAÇÕES SOBRE A EPIDEMIOLOGIA DE DENGUE EM ARAGUAÍNA, TOCANTINS

A dengue infere expressivamente sobre a saúde pública do Brasil. São diversos os Estados atingidos, dentre eles o Tocantins, cujos índices de notifcações são signifcativos com destaque para o município de Araguaína. Em virtude disso, o objetivo deste estudo foi analisar o comportamento epidemiológico da dengue em Araguaína entre o período de Janeiro de 2000 a Dezembro de 2009. A presença endêmica do agravo na região contribuiu para os altos índices de confrmação, com destaque para 2008, ano de surto epidemiológico, com aumento de 91,5% de casos confrmados com relação ao ano anterior. Apesar de elevados os casos confrmados, apenas vinte indivíduos apresentaram Febre Hemorrágica da Dengue, sem nenhuma ocorrência de óbito. Em relação aos índices anuais de infestação predial e breteau, o município de Araguaína se manteve em estado de alerta entre os anos de 2007 a 2009. Mudanças no tempo de vistoria dos imóveis contribuíram na redução de 82% dos casos em 2009. Dentro dessa perspectiva de controle é necessário incentivar à participação da sociedade para que o programa de controle da dengue possa ser de qualidade e efcaz. Descritores: Medicina Tropical; Saúde Pública; Vigilância Epidemiológica.Abstract: Dengue infers signifcantly on public health in Brazil. A number of affected states, including the Tocantins, whose indices are signifcant reports highlighting the city of Araguaina. The aim of this study was to analyse the epidemiological behavior of dengue in Araguaína from January 2000 to December 2009. The presence of endemic disease in the region contributed to the high levels of confrmation, especially for 2008, year of outbreak epidemiology, an increase of 91.5% of confrmed cases in the previous year. Although high-confrmed cases, just twenty individuals had Dengue Hemorrhagic Fever, with no deaths. Compared to the annual building infestation and Breteau, the municipality of Araguaina remained on alert between the years 2007 to 2009. Changes in the time of inspection of the property contributed to the reduction of 82% of cases in 2009. Within this framework of control is necessary to encourage the participation of society for the dengue control program can be effective and quality.Descriptors: Tropical Medicine; Public Health; Epidemiologic Surveillance

Genomic epidemiology reveals the circulation of the Chikungunya virus east/central/south african lineage in Tocantins State, north Brazil

The chikungunya virus (CHIKV) is a mosquito-borne virus of the family Togaviridae transmitted to humans by Aedes spp. mosquitoes. In Brazil, imported cases have been reported since June 2014 through two independent introductions, one caused by Asian Lineage in Oiapoque, Amapá state, North Region, and another caused by East/Central/South African (ECSA) in Feira de Santana, Bahia state, Northeast Region. Moreover, there is still limited information about the genomic epidemiology of the CHIKV from surveillance studies. The Tocantins state, located in Northern Brazil, reported an increase in the number of CHIKV cases at the end of 2021 and the beginning of 2022. Thus, to better understand the dispersion dynamics of this viral pathogen in the state, we generated 27 near-complete CHIKV genome sequences from four cities, obtained from clinical samples. Our results showed that the newly CHIKV genomes from Tocantins belonged to the ECSA lineage. Phylogenetic reconstruction revealed that Tocantins’ strains formed a single well-supported clade, which appear to be closely related to isolates from the Rio Grande do Norte state (Northeast Brazil) and the Rio de Janeiro state (Southeast Brazil), that experienced an explosive ECSA epidemic between 2016–2019. Mutation analyses showed eleven frequent non-synonymous mutations in the structural and non-structural proteins, indicating the autochthonous transmission of the CHIKV in the state. None of the genomes recovered within the Tocantins samples carry the A226V mutation in the E1 protein associated with increased transmission in A. albopictus. The study presented here highlights the importance of continued genomic surveillance to provide information not only on recording mutations along the viral genome but as a molecular surveillance tool to trace virus spread within the country, to predict events of likely occurrence of new infections, and, as such, contribute to an improved public health service

Circulation of Dengue Virus Serotype 1 Genotype V and Dengue Virus Serotype 2 Genotype III in Tocantins State, Northern Brazil, 2021–2022

In Brazil, the state of Tocantins, located in north-central Brazil, has experienced a significant number of cases of arboviral disease, particularly Dengue virus (DENV). This study aimed to deepen the knowledge on DENV circulation within that state by conducting full genome sequencing of viral genomes recovered from 61 patients between June 2021 and July 2022. There were a total of 8807 and 20,692 cases in 2021 and 2022, respectively, as reported by the state’s Secretary of Health. Nucleotide sequencing confirmed the circulation of DENV serotype 1, genotype V and DENV serotype 2, genotype III in the State. Younger age groups (4 to 43 years old) were mostly affected; however, no significant differences were detected regarding the gender distribution of cases in humans. Phylogenetic analysis revealed that the circulating viruses belong to DENV-1 genotype V American and DENV-2 genotype III Southeast Asian/American. The Bayesian analysis of DENV-1 genotype V genomes sequenced here are closely related to genomes previously sequenced in the state of São Paulo. Regarding the DENV-2 genotype III genomes, these clustered in a distinct, well-supported subclade, along with previously reported isolates from the states of Goiás and São Paulo. The findings reported here suggest that multiple introductions of these genotypes occurred in the Tocantins state. This observation highlights the importance of major population centers in Brazil on virus dispersion, such as those observed in other Latin American and North American countries. In the SNP analysis, DENV-1 displayed 122 distinct missense mutations, while DENV-2 had 44, with significant mutations predominantly occurring in the envelope and NS5 proteins. The analyses performed here highlight the concomitant circulation of distinct DENV-1 and -2 genotypes in some Brazilian states, underscoring the dynamic evolution of DENV and the relevance of surveillance efforts in supporting public health policies

Genomic Epidemiology of SARS-CoV-2 in Tocantins State and the Diffusion of P.1.7 and AY.99.2 Lineages in Brazil

Tocantins is a state in the cross-section between the Central-West, North and Northeast regions of Brazilian territory; it is a gathering point for travelers and transportation from the whole country. In this study, 9493 genome sequences, including 241 local SARS-CoV-2 samples (collected from 21 December 2020, to 16 December 2021, and sequenced in the MinION platform) were analyzed with the following aims: (i) identify the relative prevalence of SARS-CoV-2 lineages in the state of Tocantins; (ii) analyze them phylogenetically against global SARS-CoV-2 sequences; and (iii) hypothesize the viral dispersal routes of the two most abundant lineages found in our study using phylogenetic and phylogeographic approaches. The performed analysis demonstrated that the majority of the strains sequenced during the period belong to the Gamma P.1.7 (32.4%) lineage, followed by Delta AY.99.2 (27.8%), with the first detection of VOC Omicron. As expected, there was mainly a dispersion of P.1.7 from the state of São Paulo to Tocantins, with evidence of secondary spreads from Tocantins to Goiás, Mato Grosso, Amapá, and Pará. Rio de Janeiro was found to be the source of AY.99.2 and from then, multiple cluster transmission was observed across Brazilian states, especially São Paulo, Paraiba, Federal District, and Tocantins. These data show the importance of trade routes as pathways for the transportation of the virus from Southeast to Northern Brazil

Genomic Epidemiology of SARS-CoV-2 in Tocantins State and the Diffusion of P.1.7 and AY.99.2 Lineages in Brazil

Tocantins is a state in the cross-section between the Central-West, North and Northeast regions of Brazilian territory; it is a gathering point for travelers and transportation from the whole country. In this study, 9493 genome sequences, including 241 local SARS-CoV-2 samples (collected from 21 December 2020, to 16 December 2021, and sequenced in the MinION platform) were analyzed with the following aims: (i) identify the relative prevalence of SARS-CoV-2 lineages in the state of Tocantins; (ii) analyze them phylogenetically against global SARS-CoV-2 sequences; and (iii) hypothesize the viral dispersal routes of the two most abundant lineages found in our study using phylogenetic and phylogeographic approaches. The performed analysis demonstrated that the majority of the strains sequenced during the period belong to the Gamma P.1.7 (32.4%) lineage, followed by Delta AY.99.2 (27.8%), with the first detection of VOC Omicron. As expected, there was mainly a dispersion of P.1.7 from the state of São Paulo to Tocantins, with evidence of secondary spreads from Tocantins to Goiás, Mato Grosso, Amapá, and Pará. Rio de Janeiro was found to be the source of AY.99.2 and from then, multiple cluster transmission was observed across Brazilian states, especially São Paulo, Paraiba, Federal District, and Tocantins. These data show the importance of trade routes as pathways for the transportation of the virus from Southeast to Northern Brazil

The Omicron Lineages BA.1 and BA.2 (<i>Betacoronavirus</i> SARS-CoV-2) Have Repeatedly Entered Brazil through a Single Dispersal Hub

Brazil currently ranks second in absolute deaths by COVID-19, even though most of its population has completed the vaccination protocol. With the introduction of Omicron in late 2021, the number of COVID-19 cases soared once again in the country. We investigated in this work how lineages BA.1 and BA.2 entered and spread in the country by sequencing 2173 new SARS-CoV-2 genomes collected between October 2021 and April 2022 and analyzing them in addition to more than 18,000 publicly available sequences with phylodynamic methods. We registered that Omicron was present in Brazil as early as 16 November 2021 and by January 2022 was already more than 99% of samples. More importantly, we detected that Omicron has been mostly imported through the state of São Paulo, which in turn dispersed the lineages to other states and regions of Brazil. This knowledge can be used to implement more efficient non-pharmaceutical interventions against the introduction of new SARS-CoV variants focused on surveillance of airports and ground transportation