1 From the Institut d'investigacions Biomediques August Pi Sunyer (IDIBAPS) (P.V., S.L.), Hospital Clinic Barcelona, Spain; and Stanford University (P.V.), CA. pvillos@stanford.edu.
2 From the Institut d'investigacions Biomediques August Pi Sunyer (IDIBAPS) (P.V., S.L.), Hospital Clinic Barcelona, Spain; and Stanford University (P.V.), CA.