Summary: | 碩士 === 國立中興大學 === 生命科學院碩士在職專班 === 95 === In this study the nerve conduits with microporous (symmetric/asymmetric porous) structure were prepared from biodegradeable polylactide (PLA) by using a phase-inverse technique. The inner surface of the films was fabricated with microgrooves to provide instructive environments. Furthermore, the substrates were grafted with chitosan-Au nanocomposites (CA) after atmosphere air plasma treatment to modify the hydrophobic surface. The permeability of the PLA films were analyzed by using bovine serum albumin. For in vitro studies, the degree of cell alignment and the proliferation of neural stem cells were evaluated. It was shown that the degree of cell alignment and cell proliferation were higher in the CA grafted PLA surface. There was no significant difference between symmetric and asymmetric porous surfaces for cell alignment. Comparing the permeability of the substrates, the asymmetric substrates with CA grafting showed the most effective diffusion (outflow > inflow). The PLA conduits were implanted in the rat sciatic nerve to test the regenerative capacity. The repair outcome was evaluated by the walking behavior, histology and immunochemistry. In vivo results demonstrated that the asymmetrical microporous conduits with chitosan-Au nanocomposite modified inner surface provided a combination of physical permissive pathway for nutrient diffusion and metabolic products removal and biological cues for regenerating axons in repairing rat sciatic nerve transactions.
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