1 From the Sanders-Brown Center on Aging (P.T.N., G.A.J.), Department of Pathology and Laboratory Medicine (P.T.N.), and Department of Neurology (G.A.J.), University of Kentucky, Lexington. pnels2@email.uky.edu.
2 From the Sanders-Brown Center on Aging (P.T.N., G.A.J.), Department of Pathology and Laboratory Medicine (P.T.N.), and Department of Neurology (G.A.J.), University of Kentucky, Lexington.