1. From the Mayo Clinic and Mayo Foundation (C.S.R., H.V.S., D.R.H.), Rochester, Minn; the University of Pittsburgh (K.S.-T., P.G.), Pittsburgh, Pa; New York Medical Center (N.M.K.), New York, NY; the Institute for Clinical and Experimental Medicine (R.J.), Prague, Czech Republic; and Duke Clinical Research Institute (M.A.S.), Durham, NC.