The anti-inflammatory effect of mammalian heparin analogues, named dermatan sulfate and heparin, isolated from the ascidian Styela plicata was accessed in a TNBS-induced colitis model in rats. Subcutaneous administration of the invertebrate compounds during a 7-day period drastically reduced inflammation as observed by the normalization of the macroscopic and histological characteristics of the colon. At the molecular level, a decrease in the production of TNF-␣, TGF-␤, and VEGF was observed, as well as a reduction of NF-B and MAPK kinase activation. At the cellular level, the heparin analogues attenuated lymphocyte and macrophage recruitment and epithelial cell apoptosis. A drastic reduction in collagen-mediated fibrosis was also observed. No hemorrhagic events were observed after glycan treatment. These results strongly indicate the potential therapeutic use of these compounds for the treatment of colonic inflammation with a lower risk of hemorrhage when compared with mammalian heparin.

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RESUMOAtividades que integrem os sistemas fisiológicos utilizando situações-problema são promissoras para resolverem uma questão do ensino de fisiologia humana que é o estudo dos órgãos e sistemas de forma isolada. A aprendizagem baseada em problemas normalmente envolve a discussão entre grupos de estudantes que podem ser estruturados de diferentes formas, dentre elas podemos destacar as estratégias colaborativa e cooperativa. Na cooperação há uma divisão de tarefas entre os membros do grupo, enquanto que na colaboração não há uma divisão de tarefas a priori. No presente trabalho iremos descrever e avaliar uma atividade que integra diferentes sistemas fisiológicos, intitulada "Qual é o Diagnóstico?". Esta foi aplicada na última aula da unidade de ensino de fisiologia humana, para 338 alunos de um Pré-vestibular Social localizado na região metropolitana do Rio de Janeiro. Estratégias cooperativa e colaborativa foram utilizadas, a fim de avaliar se a divisão de tarefas favorece a solução de um problema e verificar a percepção dos alunos acerca dessas duas estratégias. A proporção de soluções corretas para cada estratégia foi obtida a partir das respostas dadas por escrito ao final da atividade. Já a percepção dos alunos acerca das estratégias foi obtida por meio da análise do "Questionário de Avaliação". Os resultados mostraram que nas duas estratégias a atividade foi bem aceita pelos alunos que a consideraram de dificuldade mediana. No entanto, a estratégia cooperativa favoreceu a solução do problema, apesar de problemas na dinâmica de grupo terem sido mais apontados do que na estratégia colaborativa.Palavras-chave: aprendizagem colaborativa, aprendizagem cooperativa, ensino baseado na solução de problemas, fisiologia humana. ABSTRACTActivities that integrate physiological systems using problem situations are promising to solve a issue to teaching human physiology that is the study of organs and systems in isolation. Problem based learning usually involves discussion between groups of students that can be structured in different ways, among which we can highlight the collaborative and cooperative strategies. In cooperation there is a division of task among group members, while in collaborative there is no division of tasks defined a priori. In both cases the groups aim to achieve a common goal or solve a problem. In this paper we describe and evaluate

Cooperative learning is an instructional practice in which students perform activities in small groups, share resources and ideas in conditions of positive interdependence. It is a practice studied and evaluated in many countries, in the most diverse educational contexts: from pre-school to post-graduation, and it can be applied in the most diverse disciplines and school curricula. Contradictorily, cooperative learning is still an incipient practice in Brazil. In this work, which is strictly theoretical, a characterization of the fundamentals of cooperative learning, its conditions for implementation and the teaching strategies that are based on this practice were carried out. Surveys were made about the effectiveness of this practice in relation to others already traditionally established, such as competition and individualism. In the article, considerations about the teaching role as a guide for this practice are highlighted. At the end, we sought to associate aspects of cooperative learning in favor of a specific area: science teaching.