Tissue biodegradability

Bioconcentration Refers to the process in which chemicals concentrate in plant and animal tissues. Biodegradable Refers to waste material that is capable of being broken down by bacteria into basic elements. 

Vieira AC, Guedes RM, Marques AT. Development of hgament tissue biodegradable devices a review. J Biomech 2009 42 2421-30. 

Despite the universal use of sutures for wound closure, there is a need to utilize adhesives instead, because of their ease of use and the reduced risk of infection. Alkyl cyanoacrylate adhesives have been studied extensively for this use, and a significant amount of research has been performed to evaluate their interaction with living tissue [40,41 J. They have been approved for external use only, because of concerns with the fact that the polymers do not readily biodegrade and can cause inflammation around the area to which it was applied. However, these concerns are reduced for -butyl cyanoacrylate, as compared to the ethyl cyanoacrylate. There is even some evidence that their use as liquid sutures actually reduces the rate of infection around the healing wound or surgical incision [42J. 

Substances which function as tissue adhesives have the unique ability to remain in contact with tissues in localized areas for prolonged periods of time. Not only does the tissue adhesive function as a glue but it has the capacity to serve as a slow release mechanism for drug delivery as it is biodegraded. 

Poly(malic acid) is of pharmaceutical interest because its chemical derivatives may harbor both tissue-specific homing molecules and therapeutic effectors to be used for tissue (tumor) targeting in chemotherapy [2]. Because of its efficient production by fermentation, its biodegradability and nontoxicity, it is also considered as raw material in the industrial production of detergents, glues, and plastic materials. 

The rate of in vivo biodegradation of subcutaneous implanted films was very high for chitin compared with that for deacetylated chitin. No tissue reaction was foimd with highly deacetylated chitosans, although they contained abundant primary amino groups [240]. 

EDI), and water to produce a group of biodegradable PU foams. The interconnected pores varied in size from 10 to 2 mm in diameter. Rabbit bone-marrow stromal cells cultured on the materials for up to 30 days formed multilayers of confluent cells and were phenotypically similar to those grown on tissue culture PS. It supported the adherence and proliferation of both bone-marrow stromal cells and chondrocytes in vitro. In subdermal implants the investigators found that the material showed infiltration of both vascular cells and connective tissue. 

Yang J, Webb A, and Ameer G. Novel citric acid-based biodegradable elastomers for tissue engineering. Adv Mater, 2004, 16, 511-516. 

Webb A, Yang J, and Ameer G. Biodegradable polyester elastomers for tissue engineering. Exp Opin Biol Ther, 2004, 4(6), 801-812. 

Pego AP, Poot AA, Grijpma DW, and Feijen J. Biodegradable elastomeric scaffolds for soft tissue engineering. J Control Rel, 2003, 87, 69-79. 

Shum-Tim D, Stock U, Hrkach J, Shinoka T, Lien J, Moses MA, Stamp A, Taylor G, Moran A, Landis W, Langer R, Vacanti JP, and Mayer JE Jr. Tissue engineering of autologous aorta using a new biodegradable polymer. Ann Thorac Surg, 1999, 68(6), 2298-304. 

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