ABSTRACT
Our previous study have demonstrated that Glycosphingolipids (GSLs) have an immunosuppressive effect on murine lymphoproliferation and IL-2 production. In the present study we examined the effect of a pool of Gangliosides (Gang) on spleen lymphocyte proliferation from either isogeneic strains of Wistar rats or BALB/c mice. Two hundred-fifty grams adult female isogeneic Wistar rats and 8-week-old BALB/c mice were used. The animals were sacrificed and the spleen harvested aseptically for cellular assays. Spleen cells suspensions were obtained by homogenization in RPMI 1640 with a loose tissue grinder. After washing, the cells were suspended in RPMI 1640 supplemented. Cell viability was measured by Trypan blue exclusion. Cells were cultured in triplicate using increasing concentrations of Gang (1; 2; 5; 10; 15; 20 mug/well) and in the presence of Concanavalin A. The cells were incubated for 48 hours and were pulsed with [³H] thymidine 18 hours prior to harvesting on glass fiber paper for counting in a beta-counter. Data were presented as rate of inhibition, as previously described. At concentrations 1 and 2 mug/well, Gang stimulated lymphoproliferation (30% and 50%, rats and mice respectively), while at concentration from 5 to 20 mug/well an increasing inhibition was observed for spleen cells from both mouse and rat (from 40% up to 80%). In preliminary studies we observed inhibition of mixed lymphocyte reaction on spleen cells from rats treated with Gang for 10 days (data not shown). Our data suggest that Gang may be investigated as a immunosuppressive drug in organ transplantation.
ABSTRACT
The present study aims to evaluate the occurrence of the bacterial transmigration in induced ezxperimental appendicitis in rabbitis through complete oclusion of the vermiform appendix. 24 New Zealand white rabbits with a body weight ranging from 2500 to 3000 grams were used. They were divided into 2 groups. The animals from group I were submitted to a median laparotomy and fragments from the spleen, left kidney, right lung, abdominal limphonode, light content from the vermiform appendix and blood from the portal vein were withdrawn for culture. The animals from group 2 were submitted to median laparotomy and complete occlusion of the vermiform appendix in order to induce appendicitis and, after 24 hours, material was collected following the steps of group 1. It was not observed an increase in bacteria in the samples analysed in the Control Group Group 1). The increase of Escherichia coli was observed in all the animals from the Experiment Group (Group 2). The bacterial transmigration occured after 24-hour observation in rabbits with experimental appendicitis.
Introdução: A queda extrínseca dos mecanismos de defesa de um hospedeiro é vista classicamente como uma infecção, que resulta na aquisição de um tecido normal, de um novo microorganismo, cuja virulência é fundamental para a sua patogenia.Na década de 50, estudos comprovaram que bactérias e endotoxinas podem ultrapassar a barreira intestinal e atingir a circulação, demonstrando ainda, que a flora intestinal representa uma importante fonte para o desenvolvimento da infecção sistêmica. Objetivo: o presente estudo visa avaliar a ocorrência de transmigração bacteriana em apendicite experimental induzida em coelhos, mediante a oclusão completa do apêndice vermiforme. Métodos: foram utilizados 24 coelhos brancos, da linhagem Nova Zelândia, com peso corporal variando de 2500 a 3000 gramas, sendo então divididos em 2 grupos. Os animais do Grupo I foram submetidos a laparotomia mediana e retirada de fragmentos do baço, rim esquerdo, pulmão direito, linfonodo abdominal, conteúdo da luz do apêndice vermiforme e sangue da veia porta para cultura. Os animais do Grupo II foram submetidos a laparotomia mediana e oclusão completa do apêndice vermiforme para a indução de apendicite e, após 24 horas, realizada a coleta do material nos moldes do Grupo I. Resultados: No Grupo controle (Grupo I), não se observou o crescimento de bactérias nas amostras analisadas. No Grupo experimento (Grupo II), observou-se o crescimento de Escherichia coli em todos os animais. Conclusão: Ocorreu transmigração bacteriana após 24 horas de observação em coelhos com apendicite experimental.