1. Departamento de Bioquímica y Biología Molecular (C.L.-O.), Facultad de Medicina, Universidad de Oviedo 33006, Oviedo, Spain;
2. Department of Pathology and Laboratory Medicine, Mount Sinai Hospital, Toronto, Ontario, Canada, M5G 1X5 and Department of Laboratory Medicine and Pathobiology, University of Toronto (E.P.D.), Toronto, Ontario M5G 1L5, Canada