1. From the Artificial Nutrition Unit (PHB, ML, and CC) and the Departments of Biochemistry (MB) and Rheumatology (EF and PDD), E Herriot Hospital, Lyon, France; the Trace Element Institute for UNESCO, Lyon, France (MB); and the Department of Biostatistics, Hospices Civils, UMR CNRS 5558, Lyon, France (CG and RE)