1. David Geffen School of Medicine at University of California (D.H.), Los Angeles, California 90095;
2. Pennington Biomedical Research Center (F.L.G.), Louisiana State University System, Baton Rouge, Louisiana;
3. Massachusetts General Hospital (L.M.K.), Boston, Massachusetts;
4. University of Texas Southwestern Medical Center (E.L.), Dallas, Texas;
5. University Clinic of Navarra (J.S.), Pamplona, Spain;
6. Geisinger Medical Center (C.S.), Danville, Pennsylvania