Experimental infection of newborn mice with murine EDIM rotavirus.

All four-day old Swiss mice whose dams were seronegative to rotavirus developed diarrhea 72 h after oral infection with EDIM rotavirus (HP strain). Electron microscopy of infected small intestine showed rotavirus particles of different sizes and morphology in the intestinal absorptive cells. In these cells rotavirus particles of 30 to 60 nm representing the various steps of virus maturation were visualized in viroplasm near the rough endoplasmic reticulum (RER). Mature rotavirus particles of 70 nm approximately were observed inside the RER of the intestinal absorptive cells. In the lamina propria rotavirus particles of approximately 30 nm and tubules were observed in phagosome-like structures of subepithelial phagocytes and were probably destroyed by lysosomal enzymes. The absence of signs of viral replication in phagocytes of lamina propria suggests that this may be the mechanism for viral antigen presentation to the host immunological system and may be one of the reasons for the fact that rotavirus infection is limited to the intestine.

Experimental infection of newborn mice with murine EDIM rotavirus

All four-day old Swiss mice whose dams were seronegative to rotavirus developed diarrhea 72 h after oral infection with EDIM rotavirus (HP strain). Electron microscopy of infected small intestine showed rotavirus particles of different sizes and morphology in the intestinal absorptive cells. In these cells rotavirus particles of 30 to 60 nm representing the various steps of virus maturation were visualized in viroplasm near the rough endoplasmic reticulum (RER). Mature rotavirus particles of 70 nm approximately were observed inside the RER of the intestinal absorptive cells. In the lamina propria rotavirus particles of approximately 30 nm and tubules were observed in phagosome-like structures of subepithelial phagocytes and were probably destroyed by lysosomal enzymes. The absence of signs of viral replication in phagocytes of lamina propria suggests that this may be the mechanism for viral antigen presentation to the host immunological system and may be one of the reasons for the fact that rotavirus infection is limited to the intestine

Toxicological and toxicogenetic effects of plants used in popular medicine and in cattle food.

Toxicological and toxicogenetic effects of aqueous (tea) and hexanic fruit extract of Indigofera suffruticosa Mill. and hydroalcoholic root extract of Solanum agrarium Stendt. were evaluated in Balb C male mice intraperitoneally exposed. A hepatotoxic effect was observed just for animals treated with aqueous fruit extract of I. suffruticosa. In relation to the toxicogenetic effect, just the group treated with 12.5% of toxic dose of aqueous fruit extract of I. suffruticosa showed a statistically significant increase in the frequency of cells with chromosome aberrations (cytogenetic effect), although a slight increase was also observed for the highest dose (25% of LD50) of hydroalcoholic root extract of S. agrarium. The results obtained show that before S. agrarium is used as medicine and before the wide use of I. suffruticosa in cattle food, careful evaluation must be done.

Estudos dos efeitos toxicológicos dos estratos de folhas e frutos de Indigofera suffructosa Mill. em camundongos. I. Estratos hexânicos / Toxicological effects of leaves and fruits extract of Indigofera suffructosa Mill. in mice I. Hexane extracts

A leguminosa indigofera suffruticosa Mill, apresenta potencial forrageiro. Folhas e Frutos foram extraídos com hexano e os extratos obtidos, administrados por via intraperitoneal em camundongos. Encontrou-se a dose tóxica de 5,0g/kg e 7,5g/kg para os extratos hexânicos de folha e fruto respectivamente. As principais alteraçöes foram observadas a nível hepático e pulmonar