51 research outputs found
Extent and distribution of calcification of both the aortic annulus and the left ventricular outflow tract predict aortic regurgitation after transcatheter aortic valve replacement
Acellular human glans extracellular matrix as a scaffold for tissue engineering: in vitro cell support and biocompatibility
Characterization of poly (L-co-D,L Lactic Acid) and a study of polymer-tissue interaction in subcutaneous implants in wistar rats
Effect of Salt Leaching on PCL and PLGA(50/50) Resorbable Scaffolds
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)The use of porous bioresorbable scaffolds in the field of tissue engineering represents an alternative for the treatment of lesions and losses of biological tissues. This work evaluates the leaching salt effect of two different processes and polymers. Dense and porous scaffolds were prepared with poly(epson-caprolactone) (PCL) and poly(D, L-lactic acid-co-glycolic acid) (50/50) (PLGA50) by casting and melting compression process. Sodium citrate with particles sizes of 180-250 mu m of diameter was used as porogen. The dense and porous samples were immersed in distilled water for 30 hours and evaluated for pH and mass variations, by scanning electronic microscopy (SEM), differential scanning calorimetric (DSC) and thermogravimetric analysis (TGA). The results of the analyses showed that the inclusion of the salt and leaching process did not affect the properties of the scaffold, indicating that the method is useful to make porous scaffolds to be potentially used in tissue engineering.1117580Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
Porous and dense poly(L-lactic acid) and poly(D,L-lactic acid co-glycolic acid) scaffolds: In vitro degradation in culture medium and osteoblasts culture
The use of bioresorbable polymers as a support for culturing cells has received special attention as an alternative for the treatment of lesions and the loss of tissue. The aim of this work was to evaluate the degradation in cell culture medium of dense and porous scaffolds of poly(L-lactic acid) (PLLA) and poly(D,L-lactic acid-co-glycolic acid) (50:50) (PLGA(50)) prepared by casting. The adhesion and morphology of osteoblast cells on the surface of these polymers was evaluated. Thermal analyses were done by differential scanning calorimetry and thermogravimetric analysis and cell morphology was assessed by scanning electron microscopy. Autocatalysis was observed in PLGA(50) samples because of the concentration of acid constituents in this material. Samples of PLLA showed no autocatalysis and hence no changes in their morphology, indicating that this polymer can be used as a structural support. Osteoblasts showed low adhesion to PLLA compared to PLGA(50). The cell morphology on the surface of these materials was highly dispersed, which indicated a good interaction of the cells with the polymer substrate. (C) 2004 Kluwer Academic Publishers.15121315132
Poly(epsilon-caprolactone) and poly(d,l-lactic acid-co-glycolic acid) scaffolds used in bone tissue engineering prepared by melt compression-particulate leaching method
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Porous bioresorbable polymers have been widely used as scaffolds in tissue engineering. Most of the bioresorbable scaffolds are aliphatic polyesters and the methods employed to prepare the porous morphology may vary. This work describes and evaluates the in vitro degradation of porous and dense scaffolds of poly(epsilon-caprolactone) (PCL) and poly(d,l-lactic acid-co-glycolic acid) (50/50) (PLGA50) prepared by particulate leaching-melt compression process. Biological evaluation was carried out using osteoblast cell cultures. The results showed an autocatalytic effect on the dense samples. Osteoblasts presented intermediate adhesion and the cell morphology on the surface of these materials was dispersed, which indicated a good interaction of the cells with the surface and the material.221023772385Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)CNPq [141582
Analysis of the Growth Pattern of Vero Cells Cultured on Dense and Porous Poly (L-Lactic Acid) Scaffolds
Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Poly (L-lactic acid) (PLLA) polymers are the most frequently used substrates for cell culture, tissue regeneration and orthopedic prostheses, mainly because of their atoxic characteristics and good biocompatibility. The objective of this study was to evaluate whether a higher density or different pore diameters (less than 45, 180-250, and 250-350 mu m) would change the growth pattern of cultured cells. The cells were found to adhere to and spread over all PLLA scaffolds studied. The cells also showed similar proliferation on dense and porous PLLA scaffolds, except for PLLA scaffolds with a smaller pore diameter. The cytochemical data showed high metabolic cellular activity on the various substrates. Overall, the results indicated satisfactory cell growth and proliferation on the different PLLA scaffolds studied, especially for those with pore diameters of 180-250 mu m and 250-350 mu m.123257263Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq
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