1. Department of Chemistry and Biochemistry and Molecular Biology Institute, University of California, Los Angeles, California 90095-1570, Research Institute of Scripps Clinic, La Jolla, California 92307, and Lipoprotein and Atherosclerosis Group, Room H460, University of Ottawa Heart Institute, Ottawa Civic Hospital, 1053 Carling Avenue, Ottawa, Ontario, Canada K1Y 4E9