Biological prostheses

Gaertner WB, Bonsack M, Delaney J. Experimental evaluation of four biologic prostheses for ventral hernia repair. J Gastrointest Surg 2007 11(10) 1275-85. 

Ratnatunga, C.P. et al.. Tricuspid valve replacement UK Heart Valve Registry mid-term results comparing mechanical and biological prostheses. Ann Thorac Surg, 1998. 66(6) p. 1940-7. 

Implantable microelectronic devices for neural prosthesis require stimulation electrodes to have minimal electrochemical damage to tissue or nerve from chronic stimulation. Since most electrochemical reactions at the stimulation electrode surface alter the hydrogen ion concentration, one can expect a stimulus-induced pH shift [17]. When translated into a biological environment, these pH shifts could potentially have detrimental effects on the surrounding neural tissue and implant function. Measuring depth and spatial profiles of pH changes is important for the development of neural prostheses and safe stimulation protocols. 

A closely related challenge is the design of materials that interact with cells or living tissues to promote desired biological responses. Such responses might be cell attachment, cellular differentiation and organization into functional tissue, or promotion of in-growth of bone into an artificial prosthesis such as an artificial hip. 

The most welcome technical achievements in life science are the ones that enhance well-being or restore impaired or lost biological functions. Rehabilitation engineering is a research field that has devoted its full spectrum of efforts to compensate for malfunctions and disorders in human biological systems. This includes the development of devices for the rehabilitation of neural disorders which are termed neural prostheses. Neural prostheses directly interface with the central and peripheral nervous system. The most commonly known neural prosthesis is the cardiac pacemaker, which has existed for more than 30 years. A variety of other lesser known devices have been developed to partially restore neural functions in disabled people. 

Greisler, H. P, New Biologic Synthetic Vascular Prosthesis, R.G. Landes, Austin, TX, 1991. 

Another ophthalmologic application of polymeric biomaterials is the development of ocular prosthesis and biologically inspired compound eyes [197,198]. Such prostheses, commonly fabricated from porous polyethylene, are designed to serve as nonfunctional artificial substitutes for enucleated eyeballs [199]. 

After implantation, the surface of the prosthesis is the first component to come into contact with the surrounding biological milieu. Therefore, surface characteristics play an important role in controlling the course of subsequent biological reactions. Antifouling materials are materials that can resist protein adsorption or microbial adhesion [205,206]. Hence, they have potential applications as surface coatings on implantable devices such as heart valves and hip joint prostheses to minimize biofihn formation and subsequent device-associated infections. 

The identification of the fundamental biological requirements of a biomaterial first requires an identification of how the biomaterial is to be used and in what type of implant medical device or prosthesis the biomaterial is to be used. Having identified the intended application of the biomaterial, the identification of the tissues that will contact the biomaterial and the implant duration of the biomaterial, medical device or prosthesis is necessary. Once these parameters have been defined, appropriate in vitro and in vivo assays can be sdected to identify the success or failure of the biomaterial and its intended application. A broad perspective in the selection of in vitro and in vivo biocompatibility assays is necessary to not only identify adverse reactions but also identify reactions that indicate the successful function of the biomaterial in its intended application. Adverse tissue responses do not necessarily reject a biomaterial from use in a medical device or prosthesis. Adverse tissue responses do require a risk... 

Cool, J. C., and Van Hooieweder, G. J. O. (1971). Hand prosthesis with adaptive internally powered fingers. Medical and Biological Engineering, vol. 9, pp. 33-36. 

The impact of materials technology on biological systems is through the development of materials that can be used in prostheses. When a prosthesis is put... 

Roballey, T. Feldman, N. Schwibner, B. H. Cosmetic and reconstructive prosthesis containing a biologically compatible rupture indicator. U.S. Pat. Appl. Publ. US 2005149186, 2005 Chem. Abstr. 2005,143, 103364. 

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