Although several reports have demonstrated physiological and behavioral changes in adult rats due to neonatal immune challenges, little is known about their effects in adolescence. Since neonatal exposure to lipopolysaccharide (LPS) alters the neural substrates involved in cognitive disorders, we tested the hypothesis that it may also alter the response to novel environments in adolescent rats. At 3 and 5 days of age, male Wistar rats received intraperitoneal injections of either vehicle solution or E.
View Article and Find Full Text PDFWe have generated proteoliposomes carrying proteins of Trypanosoma cruzi for use as immunogens in BALB/c mice. T. cruzi trypomastigote and amastigote forms were sonicated and mixed with SDS, with 94% recovery of soluble proteins.
View Article and Find Full Text PDFLiposomes have long been used as models for lipid membranes and for the reconstitution of a single or multiple proteins. Also, liposomes have adjuvant activity in vaccines against several protozoan or bacterial organisms. Thus, the main objective of the present study was to obtain a crude extract of detergent-solubilized proteins of Leishmania amazonensis amastigotes and reconstitute them into liposomes.
View Article and Find Full Text PDFProteasomes are multisubunit proteases that exist universally among eukaryotes. They have multiple proteolytic activities and are believed to have important roles in regulating cell cycle, selective intracellular proteolysis, and antigen presentation. Here we have partially purified Leishmania chagasi proteasome.
View Article and Find Full Text PDFTrypanosoma cruzi trypomastigotes treated with phosphatidylinositol-specific phospholipase C (PI-PLC) in vitro are rapidly induced to differentiate into round forms. Using confocal microscopy, we were able to show that trypomastigotes treated with PI-PLC initiate the process of flagellum remodeling by 30 sec after contact with the enzyme and amastigote-like forms are detected as early as 10 min after PI-PLC treatment. Scanning and transmission electron microscopy indicate that trypomastigotes undergo a previously undescribed process of flagellum circularization and internalization.
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