[1] Univ Tennessee, Ctr Hlth Sci, Memphis, TN 38163 USA
[2] Univ Texas Houston, Houston, TX USA
[3] Vanderbilt Univ, Nashville, TN 37235 USA
[4] Univ Arkansas, Little Rock, AR 72204 USA
[5] Indiana Univ Sch Med, Indianapolis, IN 46202 USA
[6] Univ Missouri, Kansas City, MO 64110 USA