Implementação de um Sistema b-Learning na Escola Secundária do Nambambe-Lubango

Esta dissertação tem como objecto de estudo a implementação de um sistema b-learning na Escola Secundaria do Nambambe -Lubango, uma vez que a instituição reúne condições para a sua materialização, ainda que não a tenha. Por isso, pensámos fazer um estudo pormenorizado sobre o tema, a fim de descrever e explicar as condições existentes para a sua implantação. O Sistema a ser utilizado é o Moodle, com todas as suas ferramentas e potencialidades, nomeadamente: o fórum e a avaliação, que poderão complementar as actividades presenciais com maior rigor e originalidade. A metodologia empregue é o estudo de caso com vista a explicar a implantação do b-learning que é a modalidade aceite para ser efectuada nesta instituição, a julgar pelas vantagens que ela oferece e os benefícios que trará para o processo de ensino-aprendizagem, mormente para os professores e alunos em termos de tecnologia, informação e conhecimento, libertando-se da infoexclusão digital. Com a pesquisa bibliográfica referente à temática e aplicação de um questionário dirigido aos professores e alunos que, depois de analisados os dados, podemos concluir que os inqueridos revelam competências básicas para a execução do projecto e os benefícios que este sistema oferecer para qualquer aprendente, tanto durante a vida como ao longo da vida.

Cross-presentation by WASp deficient B cells and dendritic cells

The immune system comprises of different cell types whose role is to protect us against pathogens. This thesis investigates a very important mechanism for our organism protection in a specific disorder: cross-presentation in Wiskott-Aldrich Syndrome (WAS). WAS is caused by loss-of-function mutations in the cytoskeletal regulator WASp and WAS patients suffer from eczema, thrombocytopenia, and immunodeficiency. X-linked neutropenia (XLN) is caused by gain-of-function mutations in WASp and XLN patients suffer from severe congenital neutropenia and immunodeficiency. This thesis was focused on the role of B and T lymphocytes and dendritic cells (DCs). This work will be divided into two main topics: 1) In the first part I studied the capacity of B cells to take up, degrade and present antigen. Moreover I studied the capacity of B cells to induce T cell proliferation. 2) In the second part, I studied T cell proliferation induced by dendritic cells. To increase our understanding about this mechanism, additional experiments were performed, including acidification capacity of CD8+ and CD8- DCs, reactive oxygen species (ROS) production since it is directly connected to acidification. These assays were measured by flow cytometry. Localization of Rac1 and Rac2 GTPases was assessed by confocal microscopy. Proliferation, acidification and ROS production assays were performed also with cells from X-linked neutropenia (XLN) mice. From this study we concluded that B cells cannot induce CD8+ T cell proliferation however they take up and present antigen. Moreover I have shown that increased cross-presentation by WASp KO DCs with ovalbumin is associated with decreased capacity to acidify endosomal compartment; and WASp KO CD8- DCs have increased Rac2 localization to the phagosome. XLN dendritic cells have similar acidification and ROS production capacity than wildtype cells. In conclusion, our data suggests that WASp regulates antigen processing and presentation in DCs.