The aim of the present study was to evaluate the use of collagen, elastin, or chitosan biomaterial for bone reconstruction in rats submitted or not to experimental alcoholism. Wistar male rats were divided into eight groups, submitted to chronic alcohol ingestion (G5 to G8) or not (G1 to G4). Nasal bone defects were filled with clot in animals of G1 and G5 and with collagen, elastin, and chitosan grafts in G2/G6, G3/G7, and G4/G8, respectively. Six weeks after, all specimens underwent radiographic, tomographic, and microscopic evaluations. Bone mineral density was lower in the defect area in alcoholic animals compared to the abstainer animals. Bone neoformation was greater in the abstainer groups receiving the elastin membrane and in abstainer and alcoholic rats receiving the chitosan membrane (15.78 ± 1.19, 27.81 ± 0.91, 47.29 ± 0.97, 42.69 ± 1.52, 13.81 ± 1.60, 18.59 ± 1.37, 16.54 ± 0.89, and 37.06 ± 1.17 in G1 to G8, respectively). In conclusion, osteogenesis and bone density were more expressive after the application of the elastin matrix in abstainer animals and of the chitosan matrix in both abstainer and alcoholic animals. Chronic alcohol ingestion resulted in lower bone formation and greater formation of fibrous connective tissue.
A intenção neste estudo é valermo-nos das imagens como fonte historica e a partir da leitura de um conjunto delas, produzidas na França no período que vai de 1784 a 1793, ler algumas representações da Revolução Francesa de 1789. Pretendemos ler nas imagens certa intencionalidade em retratar o presente e propor uma ação que se dá no viés do político. Para tal, selecionamos quatro (4) pinturas de Jacques-Louis David (1748-1825), que, sob nossa ótica, são representativas dos acontecimentos do período mais revolucionário que a França, e talvez o mundo, já viveu. Todos temos claro que uma imagem (uma tela) pertence à outra categoria de objeto, diferente de um texto escrito e, portanto, exige um redobrado esforço metodológico para sua leitura. E é bom que se diga que nenhum objeto de investigação é portador de verdade total e é por tal motivo que os historiadores sempre estão a reclamar uma coleção de documentos ao seu redor quando se dispõem a pesquisar.
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