[1] Harvard Med Sch, Boston, MA USA
[2] Pfizer, London, England
[3] McGill Univ, Montreal, PQ, Canada
[4] Kaiser Permanente Colorado, Denver, CO USA
[5] Univ Utah, Sch Med, Salt Lake City, UT USA
[6] Univ Messina, Messina, Italy
[7] Erasmus Univ Med Cente, Messina, Italy