BIODIVERSIDADE E INTERAÇÃO DE ECTOPARASITOS EM ROEDORES SILVESTRES Holochilus sciureus WAGNER, 1842 (RODENTIA: CRICETIDAE), CAPTURADOS NO ESTADO DO MARANHÃO, BRASIL

The aim of this study was to carry out the identification of ectoparasites fauna of H. sciureus rodents in order to describe the dynamics of inter-relationship between parasites, the host and the environment. Therefore, these animals were captured in São Bento city, state of Maranhão, Brazil. We used fine-toothed combs and metal tweezers for collecting the ectoparasites that were preserved in 70% ethanol and identified with taxonomic keys. Ecoepidemiological parameters (abundance, prevalence, maximum and average intensity) of each identified group, were calculated. The occurrence of mixed infestations was also investigated. Statistical tests of Pearson's correlation (p<0.05) were performed between the variables: abundance of ectoparasites, biological characteristics of the host and pluviometric index of the region. A total of 104 rodents was obtained and 5109 ectoparasites were identified as: Prolistrophorus spp. (59.13%), Laelaps sp. (34.9%), Hoplopleura sp. (5.83%), larvae of Metacuterebra sp. (0.03%). The values of the ecoepidemiological parameters were higher for Prolistrophorus spp. Triple infestations were the most frequent (57.74%). Among the correlations, only the total length in male rodents influenced in a negative and significant way the abundance of Laelaps sp. We made here the first records of the mite Prolistrophorus spp., the lice Hoplopleura sp. and the dipteran Metacuterebra sp. larvae for Maranhão state.Keywords. arthropod parasites; wild mammal; Maranhão. Objetivou-se realizar a identificação da ectoparasitofauna do roedor Holochilus sciureus de forma a descrever a dinâmica da inter-relação entre parasitos, o hospedeiro e o ambiente. Para tanto, esses animais foram capturados na cidade de São Bento, estado do Maranhão. Utilizaram-se pentes finos e pinças metálicas para a coleta dos ectoparasitos que foram conservados em etanol a 70% e identificados com auxílio de chaves taxonômicas. Calcularam-se parâmetros ecoepidemiológicos (abundância, prevalência, intensidade máxima e média) de cada grupo identificado. A ocorrência de infestações mistas também foi investigada. Realizaram-se testes estatísticos de correlação de Pearson (p<0,05) entre as variáveis: abundância dos ectoparasitos, características biológicas do hospedeiro e índice pluviométrico da região. Foi obtido um total de 104 roedores e 5109 ectoparasitos, que foram identificados como: Prolistrophorus spp. (59,13%), Laelaps sp. (34,9%), Hoplopleura sp. (5,83%) e larvas de Metacuterebra sp. (0,03%). Os valores dos parâmetros ecoepidemiológicos foram mais elevados para Prolistrophorus spp. As infestações triplas foram as mais frequentes (57,74%). Dentre as correlações realizadas, somente o comprimento total em roedores machos influenciou de maneira negativa e significativa a abundância de Laelaps sp. O ácaro Prolistrophorus spp., o piolho Hoplopleura e, larvas de Metacuterebra sp. constituem primeiros registros para o estado do Maranhão.Palavras-chave. artrópodes parasitos, mamífero silvestre, Maranhão

FAUNA ENDOPARASITÁRIA EM ROEDORES Holochilus sciureus (RODENTIA: CRICETIDAE), RESERVATÓRIO SILVESTRE DA ESQUISTOSSOMOSE NO MARANHÃO, BRASIL

The objective was to evaluate the endoparasitary fauna of H. sciureus, in order to identify the parasitic infections of this host and to investigate the diseases that humans can acquire when there is a proximity to these animals. To do so, these animals were captured in the city of São Bento, state of Maranhão. Captures were made using Tomahawk type traps.The feces were then collected from rodents, in which they were submitted to the methods of Kato-Katz and Hoffman, with the purpose of confirming the positivity of endoparasites, confirmed by the presence of eggs, cysts, oocysts and larvae in the feces.The prevalence rates, abundance and mean intensity of each endoparasite were calculated using specific formulas.As a result, a total of 80 rodents were obtained, with the following specimens being identified: Trichuris muris (8.45%); Nippostrongylus sp. (45.5%); Aspiculuris tetraptera (5.63%); Larvae of Strongyloides sp. (15.49%); Hymenolepis nana (2.81%); Schistosoma mansoni (22.12%); Coccidia (25.35%) and Entamoeba sp. (14.65%).Therefore, as there are reports of human cases parasitized with some of these specimens identified in rodent fecal samples, the need for measures to control the population of these rodents to avoid the transmission of diseases to humans is emphasized.Keywords: helminths; zoonotic potential; wild rodents.Objetivou-se avaliar a fauna endoparasitária do H. sciureus, com intuito de identificar as infecções parasitárias deste hospedeiro e averiguar as enfermidades que os humanos podem adquirir quando houver uma proximidade com estes animais. Para tanto, esses animais foram capturados na cidade de São Bento, estado do Maranhão. As capturas foram realizadas através de armadilhas do tipo Tomahawk. Posteriormente coletou-se as fezes dos roedores, nas quais foram submetidas aos métodos de Kato-Katz e Hoffman, com o intuito de comprovar a positividade de endoparasitos, confirmado pela presença de ovos, cistos, oocistos e larvas nas fezes. Calcularam-se as taxas de prevalência, abundância e intensidade média de cada endoparasito, através de fórmulas específicas. Como resultado, obteve-se um total de 80 roedores, sendo identificados os seguintes espécimes de parasitos: Trichuris muris(8,45%); Nippostrongylus sp.(45,5%); Aspiculuris tetraptera (5,63%); larvas de Strongyloides sp. (15,49%); Hymenolepis nana (2,81%); Schistosoma mansoni (22,12%); Coccídios (25,35%) e Entamoeba sp. (14,65%).  Portanto, como há relatos de casos humanos parasitados com alguns desses espécimes identificados nas amostrais fecais dos roedores, ressalta-se a necessidade de medidas de controle da população desses roedores para evitar a transmissão de doenças ao homem.Palavras-chave: helmintos, potencial zoonótico, roedores silvestres

Immunological mechanisms involved in macrophage activation and polarization in schistosomiasis

Human schistosomiasis is caused by helminths of the genus Schistosoma. Macrophages play a crucial role in the immune regulation of this disease. These cells acquire different phenotypes depending on the type of stimulus they receive. M1 macrophages can be ‘classically activated’ and can display a proinflammatory phenotype. M2 or ‘alternatively activated’ macrophages are considered anti-inflammatory cells. Despite the relevance of macrophages in controlling infections, the role of the functional types of these cells in schistosomiasis is unclear. This review highlights different molecules and/or macrophage activation and polarization pathways during Schistosoma mansoni and Schistosoma japonicum infection. This review is based on original and review articles obtained through searches in major databases, including Scopus, Google Scholar, ACS, PubMed, Wiley, Scielo, Web of Science, LILACS and ScienceDirect. Our findings emphasize the importance of S. mansoni and S. japonicum antigens in macrophage polarization, as they exert immunomodulatory effects in different stages of the disease and are therefore important as therapeutic targets for schistosomiasis and in vaccine development. A combination of different antigens can provide greater protection, as it possibly stimulates an adequate immune response for an M1 or M2 profile and leads to host resistance; however, this warrants in vitro and in vivo studies

Effectiveness of a handmade shell-based substrate for the breeding of Biomphalaria glabrata under laboratory conditions

Efficient snail production is essential for the proper maintenance of the Schistosoma mansoni life cycle in the laboratory. In order to improve the breeding of Biomphalaria glabrata under laboratory conditions, this study aimed to demonstrate the effectiveness of a handmade shellbased substrate on the physiological performance of B. glabrata. The shells used to make the substrate were cleaned, sterilized and macerated until a powder was obtained (yield of 92.3%). B. glabrata specimens were randomly assigned to three treatment groups: negative control group (NCG) exposed to a clay-only substrate; a positive control group (PCG) containing clay, oyster flour and calcium carbonate; and the test group (TG) with the shell-based substrate and clay. B. glabrata bred in the test group showed improved growth, sexual maturity, fertility, mortality rate, and shell morphology when compared to the NCG, and similar to the PCG. Therefore, the shell-based substrate proved to be efficient and has a low cost for the breeding of B. glabrata