1. From the Neurotoxicology Section, National Institute of Neurological Disorders and Stroke, National Institutes of Health, Bethesda, Md (Drs Chima, Agostini, and Stoner and Ms Ryschkewitsch), and UMDS Guy’s and St Thomas’ Medical and Dental School, Department of Histopathology, St Thomas Hospital, London, United Kingdom (Dr Lucas). Dr Agostini is now with the Department of Ophthalmology, Universit