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Show Helpful in transplants Key to clot-resistant material found by University research faces could be influenced by "albumin" "al-bumin" and "gama globulin," two of the major blood proteins. By precoating a variety of polymer surfaces with albumin, the researchers re-searchers found no platelet adhesion adhe-sion occurred; conversely, adhesion adhe-sion did occur in those coated with gamma globulin. Adhesion Another polymer, a polyurethane developed by the Utah group, also showed no platelet adhesion, since it absorbed albumin directly from the blood, he noted. Both types of "antra;; polymer surfaces were t? planted in the veins ol t: two weeks, he noted, ; were free of clots. "Most;; clot within two hours unler with an anti-coagulant," i. stated. Dr. Lyman emphasized : though there has been a" ress during the last decad; ficial organs, there fe been many failures due i choice of materials oi S proper usage." Scientists at the University are optimistic that a recent discovery will hasten the development of blood clot-resistant materials a key to successful implantation of artificial organs in the human body. Blood clotting and cell rupturing around implanted foreign materials has long been a medical problem, and have obstructed the use of such sophisticated devices as artificial arti-ficial hearts, lungs and kidneys. Dr. Donald J. Lyman, professor of materials science, recently told guests attending dedication ceremonies cere-monies of the Midland Macromole-cular Macromole-cular Institute in Midland, Mich., that Utah researchers "have developed devel-oped a new working theory on the causes of clotting to guide the development de-velopment of blood-compatible materials." ma-terials." New Method The scientists have also developed devel-oped a method of clotting blood on polymer surfaces which allows them to apply the new theory. "This should enable us to develop improved heart valves, vascular grafts, artificial hearts and an assortment as-sortment of other devices for the removal of poisons from the body," predicted Dr. Lyman, a key figure in the University's artificial organ research. Mysteries Under a National Science Foundation Foun-dation program, researchers have probed the mysteries of the interaction inter-action of blood, tissue fluids and cells with polymeric implant materials, ma-terials, such as plastic. "Much of our work has been based on the premise that a specific spe-cific clotting substance in the blood plasma is absorbed into the artificial surface and triggers clot formation," Dr. Lyman explained. "However, our studies indicate that clotting on ploymer surfaces may be similar to the natural clotting clot-ting of blood on damaged blood vessel walls," he stated. 'Tiny 'Platelets' adhere to the polymer surface as they do to damaged vessel walls, causing a clot," he added. Further study has shown that Platelet adhesion to polymer sur- |