Resumo: Duas áreas localizadas no Estado do Tocantins, Brasil foram selecionadas para o levantamento da comunidade de abelhas, uma área com vegetação predominante de Cerrado e outra em ecótono Cerrado-Amazônia. Durante cinco expedições em cada área em um período de 12 meses, entre os anos de 2019 e 2020 foram coletados 771 espécimes de abelhas, distribuídas em quatro famílias: Apidae, com a maior abundância e riqueza de espécies, seguida de Halictidae, Megachilidae e Andrenidae. Trigona pallens (Fabricius) (Apidae) foi a espécie com maior abundância em ambas as áreas, totalizando 118 espécimes, o que correspondeu a 26,9% da abundância total de indivíduos da tribo Meliponini. De um modo geral, a comunidade apresentou muitas espécies com poucos indivíduos e poucas espécies com muitos indivíduos. A metodologia de coleta com uso de rede entomológica permitiu a coleta do maior número de indivíduos e de espécies em relação a outros três métodos utilizados. Em ambas as áreas, poucas espécies foram classificadas como muito frequentes (MF) e muito abundantes (MA), de acordo com as classes de frequência e de abundância. Também para ambas as áreas, grande parte das espécies foram constantes (W) e um baixo número de espécies dominantes (D), com mais de 70% delas consideradas acidentais (Z). O presente estudo revelou que tanto o Cerrado como a área de transição Cerrado-Floresta Amazônica apresentou alta riqueza de espécies em comparação com outras áreas destes biomas amostradas no Brasil.

Abstract: Two sites located in Tocantins State, Brazil, were selected for the bee’s community survey. One of them was mostly covered by Cerrado vegetation and the other one is located in the Cerrado-Amazon Rainforest ecotone. Five expeditions were performed in each site throughout a 12-month period, between 2019 and 2020. The total of 771 bee specimens were collected and distributed into four families. Apidae presented the greatest species abundance and richness, it was followed by Halictidae, Megachilidae and Andrenidae, respectively. Trigona pallens (Fabricius) (Apidae) was the species presenting the greatest abundance in both sites, it totaled 118 specimens, which corresponded to 26.9% of the total abundance of individuals belonging to tribe Meliponini. In general, the community presented several species with few individuals and few species with many individuals. Bee collections were performed by using three different methodologies, among them one finds sampling based on the entomological net method, which allowed collecting the largest number of both individuals and species in comparison to the other used methods. Based on the frequency and abundance classes, only few species were classified as very frequent (VF) and very abundant (VA) in both sites based on the frequency and abundance classes. Most species were constant (W) in both regions, and there was a small number of dominant species (D); moreover, more than 70% of the sampled species were considered accidental (Z). According to the present study, either Cerrado or Cerrado-Amazon Rainforest studied sites presented higher species richness than other sites in these biomes sampled in Brazil.

Abstract INTRODUCTION: Malaria and leishmaniasis are prevalent in tropical regions, which have environmental characteristics that are highly favorable to protozoa and vectors of these diseases; the transmission of these infections in sub-tropical regions, although recognized, represents only a small fraction of cases. Plants are constantly being used in the search for and acquisition of new drugs, and many compounds derived from them have been used to combat various diseases. In this study, we evaluated the action of the dichloromethanolic extract of Myrciaria dubia leaves against the protozoa Plasmodium falciparum, Leishmania amazonensis, Leishmania braziliensis, and Leishmania chagasi through bioassays. METHODS The extract from M. dubia was tested for its anti-P. falciparum activity in an anti-histidine-rich protein II immunosorbent assay. The antileishmanial assays were performed using the resazurin method, while cytotoxicity against human hepatoma (HepG2) strain was determined using the colorimetric MTT [3-(4, 5-dimethyl-2- thiazolyl)-2, 5-diphenyl-2H tetrazolium bromide] method. RESULTS The M. dubia extract presented a half-maximal inhibitory concentration equal to 2.35 (1.05)μg/mL for P. falciparum, 190.73 (6.41) μg/mL for L. amazonensis, and greater than equal to 200µg/mL for L. chagasi and L. braziliensis strains. The cytotoxic concentration for 50% of the cells was above 500μg/mL for HepG2, indicating no toxicity and greater selectivity against parasites. CONCLUSIONS The results obtained indicate the presence of antiplasmodial and leishmanicidal bioactive compounds in the dichloromethanolic extracts of M. dubia leaves, and point towards future studies to elucidate the mechanism of action for each physiological effect.

INTRODUÇÃO: O estudo foi realizado com o objetivo de identificar, através da PCR, a presença da infecção por Leishmania (Leishmania) chagasi em cães no município de Palmas, no Estado do Tocantins, Brasil, de modo a elencar os hot spots de cães infectados no município e associar sua ocorrência a alterações ambientais marcantes nos locais de captura. MÉTODOS: O DNA foi extraído do sangue dos cães e as reações de PCR foram realizadas com os primers RV1/RV2. Após o screening da população estudada, foram detectadas as regiões do município que apresentavam as maiores ocorrências da infecção canina. Esses locais foram visitados, e parâmetros de distúrbio ecológico com origem antrópica foram avaliados. RESULTADOS: Algumas características importantes foram constantes entre as regiões visitadas, entre elas a baixa urbanização, inexistência de coleta pública de esgoto, coleta publica de lixo pouco abrangente, lotes vagos com vegetação alta, e matéria orgânica em decomposição, com destaque para criação de cães soltos, e aves nas residências. CONCLUSÕES: A metodologia adotada para screening da população se mostrou bastante eficiente, sobretudo na avaliação de um grande número de indivíduos em tempo reduzido, com alto grau de automatização. Os resultados apresentados indicam associação entre os parâmetros observados e a ocorrência da infecção em cães. O modelo apresentado no município é ideal para estudos do desenvolvimento da doença, bem como sua expansão, além da avaliação das medidas de controle adotadas para a leishmaniose visceral canina.

INTRODUCTION: The aim of the present study was to identify the presence of Leishmania (Leishmania) chagasi infection in dogs in the City of Palmas, Tocantins, Brazil, using the PCR technique to list the hot spots of infected dogs in the city and associate their occurrence to significant environmental changes at capture sites. METHODS: DNA was extracted from blood of dogs, and the PCR were performed with primers RV1/RV2. After screening the population studied, the regions of the city that had the highest occurrence of canine infection were detected. These sites were visited, and ecological parameters denoting anthropogenic disturbance were evaluated. RESULTS: Some important features were listed in the regions visited, such as low urbanization, lack of public collection of sewage, limited garbage collection, vacant lots with tall vegetation, decaying organic matter, and, most importantly, the occurrence of stray dogs and poultry in homes. CONCLUSIONS: The methodology for screening the population was very efficient, especially in evaluating a large number of individuals in a short time, with a high degree of automation. The results indicate an association between the observed parameters and the occurrence of infection in dogs. The model presented in the city is ideal for studies of disease progression and expansion and for the evaluation of control measures adopted for canine VL.