Visceral leishmaniasis (VL) caused by Leishmania chagasi is a growing public-health problem in many parts of the New World. Although several studies have focused on the consequences of environmental damage, human migration and land occupation on the incidence of VL, the effects on the disease of the substandard living conditions that often result from the process of urbanization have not been investigated in detail. The present study was based in the Brazilian city of Teresina, where, since 1980, there have been two large outbreaks of VL (one in 1981-1985 and the other in 1993-1996), each involving at least 1000 newly reported cases. The role of household structure and the provision of urban services in the city, as predictors of the occurrence of VL, was studied in a case-control investigation. After controlling for age, crowding, and the background incidence of VL in the area where the subjects lived, the risk of acquiring the disease was found to be significantly higher for those who lived in houses with an inadequate sewage system and those who had no regular rubbish collection. Improving household structure and providing basic urban services might be effective strategies for controlling the spread of VL in urban areas.

Resumo -O objetivo deste trabalho foi avaliar o efeito de métodos de extração da oleosidade de grãos de pólen de bacurizeiro (Platonia insignis), sobre sua viabilidade. Avaliaram-se sete tratamentos para a extração de lipídios do pólen, cinco deles por imersão em éter de petróleo por 30 s (T1), 60 s (T2), 300 s (T3), 600 s (T4), e 900 s (T5), e dois por imersão em 25% de álcool e 75% de éter petróleo por 60 s (T6) e 900 s (T7); e um tratamento-controle, sem a adição de solventes. Posteriormente, os grãos de pólen desengordurados foram submetidos a um teste de germinação in vitro. Os grãos de pólen submetidos a T2, T3, T4 e T5 apresentaram teores de lipídios menores do que o do tratamento-controle. O tratamento T2 promoveu a maior germinação dos pólens.Termos para indexação: Platonia insignis, Clusiaceae, armazenamento de pólen, viabilidade do pólen. Conservation and degreasing of bacury pollen grainsAbstract -The objective of this work was to evaluate the effect of methods of oil extraction from bacury (Platonia insignis) pollen grains, on their viability. Seven treatments were evaluated for lipid extraction of pollen grains, five of which by immersion in petroleum ether for 30 s (T1), 60 s (T2), 300 s (T3), 600 s (T4), and 900 s (T5), and two treatments by immersion in 25% alcohol and 75% petroleum ether for 60 s (T6) and 900 s (T7); besides a control without solvents. Subsequently, degreased pollen grains were subjected to an in vitro germination test. Pollen grains subjected to T2, T3, T4, and T5 showed lower lipid content than the control treatment. The T2 treatment provided the highest germination of pollen.