1. Section of Biochemistry and Molecular Biology, Department of Chemistry, Faculty of Medicine, University of Catania, Catania, Italy.
2. Department of Chemistry, Center of Membrane Sciences, and Sanders-Brown Center on Aging, University of Kentucky, Lexington, Kentucky.
3. Institute of Neurological Sciences, National Research Council (CNR), Catania, Italy.
4. Department of Biochemistry, University of Rochester, Rochester, New York.