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Silicosis is a chronic progressive granulomatous and fibrotic lung disease caused by inhaled silica. Although the causative agent is known, the pathogenesis, especially the immunologic response, is not well understood. We examined two important components of cell-mediated immune responses in the lungs of rats with silica-induced lung disease, i.e., class II (Ia) antigen expression and IL-1 production. The relative density of Ia was examined on isolated alveolar macrophages and type II cells with a solid-phase cellular radioimmunoassay and the percent of Ia positive cells was determined by an indirect immunofluorescent technique. There was a three-fold increase of Ia expression on the alveolar macrophages and nearly a two-fold increase on type II cells from rats with silicosis compared to normal rats. The percent of alveolar type II cells positive for Ia increased by 20%, and the alveolar macrophages increased by 40%. IL-1 in supernatants from cultured alveolar macrophage was measured by the amount of DNA synthesis in an IL-1 dependent cell line (D10). A six-fold increase in IL-1 secretion was noted in macrophage supernatants derived from silica-treated animals. We conclude that in this animal model of silicosis, a local amplification of cell-mediated immune responses may be instrumental in the pathogenesis.

Nocturnal behavior of non-bloodfed females of Aedes aegypti and Aedes albopictus was studied using an automatic recording device equipped with a photoelectric sensor. Carbon dioxide, heating, and the contrast of the black and white colors were used as attractive cues for mosquitoes. The nocturnal host seeking activity positively correlated with the increasing light intensity in both species. Ae. aegypti was found to be more sensitive to light than Ae. albopictus. The threshold of light intensity for the activation of the nocturnal host seeking activity was < 0.1 lx (ca. 0.01 foot candle) in Ae. aegypti and > 10 lx (ca. 1 foot candle) in Ae. albopictus, respectively. Complete darkness during the daytime deactivated the host seeking activity of both species, irrespective of their increasing flight activity controlled by their intrinsic circadian rhythms. This suggested that visual cues are indispensable for host seeking behavior. The eye parameter value, the product of the ommatidial diameter, and the interommatidial angle were significantly larger in Ae. aegypti than those in Ae. albopictus, indicating that the eye of Ae. aegypti is more adapted to a darker environment., 長崎大学学位論文 学位記番号:博（医）乙第1,782号 学位授与年月日:平成19年10月31日, Journal of medical entomology 42(3), pp.312-318;2005

We investigated the spatial distribution and pyrethroid susceptibility of the mosquito larvae belonging to Aedes albopictus and Culex pipiens group in catch basins located in parks in Nagasaki city, Nagasaki, Japan. Among the 308 parks located in the central regions of the city, 194 were investigated. Cx. pipiens group larvae were collected from 31 sites; larvae of Ae. albopictus, from 34 sites. The Cx. pipiens group larvae were identified by PCR: 93.4% were found to belong to Cx. pipiens pallens, and 0.9%, to Cx. pipiens form molestus. A bioassay was performed by observing the knockdown of larvae during 30-min exposures to 0.4- and 0.1-ppm solutions of d-allethrin. High tolerance to d-allethrin (susceptibility index = 36) was observed in only 1 colony of Cx. pipiens pallens across 24 sites. On the other hand, Ae. albopictus showed high tolerance (susceptibility index > 30) in 8 of 22 sites; this indicated that Ae. albopictus populations tolerant to pyrethroids were spreading widely in Nagasaki city. The organized and massive larvicidal treatment of graveyard containers with DDT in the 1950s was thought to be one of the main causes for the development of pyrethroid resistance in Ae. albopictus., Japanese Journal of Infectious Diseases, 63(1), pp.19-24; 2010