[1] Stanford Univ, Sch Med, Mol Imaging Program Stanford MIPS, Dept Radiol, Stanford, CA 94305 USA
[2] Stanford Univ, Sch Med, Dept Bioengn, Bio X Program, Stanford, CA 94305 USA
[3] Univ Mississippi, Sch Pharm, Dept Med Chem, University, MS 38677 USA
[4] W Virginia Univ, Sch Pharm, Dept Basic Pharmaceut Sci, Morgantown, WV 26506 USA