N. C. Leone

Macular degeneration associated with age and drusen, an important cause of severe visual loss in older persons, is of unknown cause. The sensory retina and retinal pigment epithelium, which are cell layers in zinc, appear to be prominently involved in the disease process. Because zinc plays a role in the metabolic function of several important enzymes in the chorioretinal complex, we undertook a prospective, randomized, double-masked, placebo-controlled investigation of the effects of oral zinc administration on the visual acuity outcome in 151 subjects with drusen or macular degeneration. Although some eyes in the zinc-treated group lost vision, this group had significantly less visual loss than the placebo group after a follow-up of 12 to 24 months. This is the first controlled oral intervention study to show a positive, if limited, treatment effect in macular degeneration, a major public health problem. Because of the pilot nature of the study and the possible toxic effects and complications of oral zinc administration, widespread use of zinc in macular degeneration is not now warranted.

I. Zipkin, F. J. McClure, N. C. Leone, W. A. Lee, Fluoride Deposition in Human Bones after Prolonged Ingestion of Fluoride in Drinking Water, Public Health Reports (1896-1970), Vol. 73, No. 8 (Aug., 1958), pp. 732-740

gross physical defects.

Hereditary multiple exostosis (HME), a bone tumor first described by Virchow, has been studied over a period of 15 years on a comparative basis. The horse, an excellent biomedical model for this physically deforming multiple bone tumor in man, has been utilized in this study. The etiology, hereditary pattern, potential for malignancy and other aspects of this strange affliction need additional clarification. This in-depth study of 261 individuals from 144 families was compared with that of 55 horses bearing the HME trait, selectively bred and studied over the same period. Important information has been collected and evaluated about this condition that is suspect of being frequently missed diagnostically, with a higher incidence in humans that recognized. Continuing development studies of offspring of the original study participants; sarcomatous transformation monitoring; and recently developed genetic techniques should add to our understanding of this puzzling hereditary condition.