[1] NIA, Lab Neurogenet, NIH, Bethesda, MD 20814 USA
[2] Van Andel Res Inst, Ctr Neurodegenerat Sci, Grand Rapids, MI 49503 USA
[3] Eunice Kennedy Shriver Natl Inst Child Hlth & Hum, Cell Biol & Neurobiol Branch, NIH, Bethesda, MD 20814 USA
[4] Univ Reading, Sch Pharm, Reading RG6 6AP, Berks, England
[5] UCL, UCL Sch Pharm, Dept Pharmacol, 29-39 Brunswick Sq, London WC1N 1AX, England
[6] Merck & Co Inc, 33 Ave Louis Pasteur, Boston, MA 02115 USA