(From Voice of America). If we can build artificial prosthetic arms, why not artificial, prosthetic skin or even blood vessels? The technology of artificial replacements blends into tissue engineering at its cutting edge, where work progresses on a competing set of methodologies to replace or repair damaged tissues and organs. "With a $6 million dollar grant from the U.S. Army, the Portland laboratory is studying elastin and other substances as tools for army medics on the battlefield. One of the products they developed is a patch made from chitosan, which is a fiber extracted from the shells of crustaceans, like shrimp and crabs. The bandage stops serious bleeding by fusing itself directly to a wound ... Dr. Gregory and his team hope to develop elastin tissue for all kinds of replacements: skin, stomachs, intestines, arteries and eventually entire body parts."