Objective To evaluate the in vitro effetcs of caffeine on proliferation, apoptosis a nd gene transcripts expression of chondrogenic differentiation in growth cartilage. Methods The cartilaginous epiphyses of femurs of newborn rats, which were divided into two subgroups: treated with caffeine and control group, both observed over the time periods of 0, 7, 14 and 21 days. The cartilaginous epiphyses of femurs of each subgroup and each time span were subjected to histomorphometric, immunohistochemical analysis, Tunel technique and RT-PCR in real time. Results The decrease in proliferative activity and the increase of apoptotic chondroblasts at 21 days were found regardless of the subgroup. However, the decrease in cell proliferation caused by caffeine was lower than in the control group and significantly increased the expression of gene transcripts for chondrogenic differentiation, represented by Sox-9 and Runx-2. However, the in vitro culture with caffeine revealed antagonistic effects: despite the positive effect on chondroblasts proliferation and differentiation, caffeine increased apoptosis, characterized by increased expression of caspase 3 and of the number of cells undergoing apoptosis (p<0.05). Conclusion Caffeine presents antagonistic effects in vitro on growth cartilage, increasing the proliferation, differentiation and cell apoptosis. Experimental Study.
Em 2009 surge o novo ENEM que se constitui hoje como uma das principais avaliações no cenário da educação brasileira e é entendido como uma regulador da qualidade da educação básica. Os documentos oficinais do ENEM mostram que esse exame se baseia nos conceitos de competências e habilidades, prezando, entre outras coisas, pela interdisciplinaridade, contextualização e situações-problemas. Portanto, a concepção teórica do ENEM vai ao encontro com uma abordagem Ciência-Tecnologia-Sociedade (CTS), o que é essencial para formação de um cidadão ativo e participativo. Neste trabalho identificamos, categorizamos e analisamos a abordagem CTS expressas nas questões de Biologia do ENEM de 2009 a 2014. Seguindo a metodologia de Bardin as questões foram classificadas e analisadas. Concluímos que o ENEM representa um avanço em relação aos tradicionais vestibulares, mas que ainda são necessárias modificações para que as suas questões se aproximem mais de uma abordagem CTS.
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