1. From the National Heart, Lung, and Blood Institute, National Institutes of Health, Bethesda, MD (J.R.K., R.B., K.M.B.); University of Connecticut, Hartford, CT (P.D.T.); University of Missouri-Kansas City, Kansas City, MO (J.L.); Children's National Medical Center, Washington, DC (C.I.B., K.M.B.); University of Utah, Salt Lake City (J.B.); Tufts University, Boston, MA (J.T.C., L.L.); University of Padova Medical School, Padova, Italy (D.C.); University of Washington, Seattle, (J.D., D.S.); Johns...