The spatial distribution of Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae) was analysed in ornamental crops (roses and spray-type carnations) and horticultural crops (pepper and strawberries), inside greenhouses, using sticky traps. In ornamental crops, at low population densities, during the winter, there was not a constant location of the isolated foci of infestation, from one week to the next, or a specific pattern of variation in that location. In spray-type carnations, pepper and strawberries, at higher population densities, in spring and summer, the basic units of distribution were the individuals, and they were aggregated. For roses, at those population levels, a random distribution was observed, with a tendency for aggregation. The number of traps needed to estimate population densities, in each crop, was evaluated for two fixed levels of precision (0.10 and 0.25) and results are indicated and discussed.
Authors:Gabrielle Souza Rocha, A. Fonseca, Michelle Rodrigues, F. Dantas, A. Caldeira-de-Araujo, and R. Santos
The aim of this work was to evaluate, by comet assay, the possible inducing of DNA lesions in peripheral blood mononuclear cells of rats subjected to acute or chronic food deprivation. Wistar male rats were subjected to 72 h of partial (50%), or total acute food deprivation, and then allowed to recover for different time periods (24, 48 and 72 h). In other experiments, comet scores were determined in peripheral blood mononuclear cells of rats subjected to chronic food deprivation (25% and 50%) for 50 days. Blood aliquots were obtained before, during and after food deprivation. Comet assay was carried out, the comet units photographed and scored (class 0 up to 3). Acute and chronic food-deprived rats presented peripheral blood mononuclear cells with DNA lesions (comet classes 1, 2 and 3) and a significant increase (
< 0.05) in the number of comet units compared with its basal level. The increase was proportional to acute food deprivation time, but after being taken off, it progressively returned to basal level after 48 h (partial group) or 72 h (total group). Chronic food-deprived rats presented a progressive increase of comet score up to 5 days, and a decrease thereafter to reach a basal level. Possible mechanisms of DNA lesions are discussed.
Authors:Ingrid E. Pereira, Kyssia P. Silva, Laura M. Menegati, Aimara C. Pinheiro, Elaine A. O. Assunção, Maria De Lourdes P. Araújo, Elfadil Abass, Malcolm S. Duthie, Ulrich Steinhoff, and Henrique C. Teixeira
Control of canine visceral leishmaniasis (CVL), a major zoonotic disease in Brazil and many other tropical and subtropical countries, remains difficult as an accurate and reliable diagnosis is still missing. In endemic regions, infected dogs are the main parasitic reservoir host of human Visceral leishmaniasis (VL) infection. Vaccination of dogs against Leishmania infection constitutes an important strategy to prevent or to better control CVL, thus, a serological test that can discriminate between antibodies induced by immunization versus infection is highly desirable in order to improve and simplify diagnosis. Here, four recombinant proteins were evaluated for their ability to detect and differentiate between dogs that are infected with Leishmania or have been immunized with the anti-Leishmania vaccine Leish-Tec®. Receiver operating characteristic (ROC) curve analysis of the four Leishmania-specific IgG ELISA revealed superior performance of rK28, followed by rKLO8, rK39 and rLb6H. The rK28-based ELISA revealed not only the best accuracy against CVL, but also the lowest cross-reactivity with sera from Leish-Tec® immunized dogs. Our data show that the rK28-based ELISA is highly suitable for CVL screening as it shows high sensitivity with simultaneous low cross-reactivity. Further, the high specificity of the rKLO8 indicates its suitability for the confirmation of CVL diagnosis.