Infecção natural por tripanosomatídeos (Kinetoplastida: Trypanosomatidae) em Lutzomyia umbratilis (Diptera: Psychodidae) em áreas de leishmaniose tegumentar americana no Amazonas, Brasil

Durante o período de 2002 a 2003 foram realizadas coletas de flebotomíneos em duas áreas do estado do Amazonas (Base de treinamento militar - BI1 e Tarumã Mirim). Nessas coletas foram capturadas um total de 1.440 fêmeas de Lutzomyia (Nyssomyia) umbratilis. Lu.umbratilis é a principal responsável pela transmissão da Leishmaniose Tegumentar Americana (LTA) ao norte do Rio Amazonas. Do total coletado apenas 15 espécimens (ou 1,04%) apresentaram infecção natural por tripanosomatídeos, sendo 12 na BI1 e 3 em Tarumã-Mirim. Isso representou uma taxa de infecção de 1,66% (12 dos 720 capturados em BI1) e 0,42% (3 dos 720 em Tarumã-Mirim). Estes resultados confirmam as informações prévias por outros autores de reduzidos valores de infecção natural por tripanosomatídeos em flebotomíneos, mesmo em áreas altamente endêmicas para leishmaniose.During the period of 2002 to 2003, there were collected sand flies in two areas of Amazon State (Forest Combat Training Base - BI1 and Tarumã-Mirim). Were collected the 1440 L. (Nyssomyia) umbratilis female. Lu. umbratilis is the main responsible for the transmission of American Tegumentary Leishmaniasis (ATL) in the northern of Amazon River. Only 15 specimens (or 1,04%) presented natural infection with trypanosomatids, being 12 at Bl1 and 3 at Tarumã-Mirim. The infection rate was 1,66% (12 of the 720 collected at BI1) and 0,42% (3 of the 720 at Tarumã-Mirim). These results confirm the previous informations described by other authors that insects have low rates of natural infection by trypanosomatids even in high endemic areas for Leishmaniasis

Isolation, primary culture and morphological characterization of oenocytes from Aedes aegypti pupae

AbstractOenocytes are ectodermic cells that participate in a number of critical physiological roles such as detoxification and lipid storage and metabolism in insects. In light of the lack of information on oenocytes from Aedes aegypti and the potential role of these cells in the biology of this major yellow fever and dengue vector, we developed a protocol to purify and maintain Ae. aegypti pupa oenocytes in primary culture. Ae. aegypti oenocytes were cultured as clustered and as isolated ovoid cells with a smooth surface. Our results demonstrate that these cells remain viable in cell culture for at least two months. We also investigated their morphology in vivo and in vitro using light, confocal, scanning and transmission electron microscopes. This work is the first successful attempt in isolating and maintaining Ae. aegypti oenocytes in culture, and a significant step towards understanding the role of this cell type in this important disease vector. The purification and the development of primary cultures of insect oenocytes will allow future studies of their metabolism in producing and secreting compounds