Neurobiolo,~,y ~lAging, Vol. 7, pp. 133-137, 1986. '~ Ankho InternationalInc. Printed in the U.S.A. 0197-4580/86 $3.00 + .00 MEETING REPORT Thirteenth International Congress of Gerontology MICHAEL J. PONTECORVO Nova Pharmaceutical Corporation, 5210 Eastern Ave., Baltimore, MD 21224-2788 DONALD K. INGRAM Gerontology Research Center, N1A, Francis Scott Key Medical Center, Baltimore, MD 21224 AND REGINALD L. DEAN Medical Research Division of American Cyanamid Company, Lederle Labs, Pearl River, NY 10965 THE 13th International Congress of Gerontology, under the auspices of the International Association of Gerontology and hosted by the American Geriatrics Society, the Canadian Association of Gerontology and the Gerontological Society of America, was held July 12-16, 1985 at the New York Hilton Hotel, New York City. With the theme entitled -Aging: The Universal Experience," the program of the Congress was designed to meet the educational needs of a broad spectrum of scientists, practioners and administrators. Each day, sections of the program were devoted to four main areas of concern: (1) biology, (2) clinical medicine, (3) behav- ior and social sciences, and (4) social research, planning and practice. The program emphasized current multidisciplinary aspects of gerontology. Because it is difficult to cover every aspect of neurobiology of aging presented at a meeting of this magnitude, only major topics involving several symposia or paper sessions will be presented here. NEUROCHEMICAL AND NEUROPATHOLOGICAL CHANGES WITH AGE AND ALZHE1MER'SDISEASE Four symposia as well as a number of paper and poster sessions, dealt with the neurochemical and neuropathologi- cal changes resulting from aging and Aizheimer's disease. Dr. Roses (Duke University Medical Center, NC) discussed Down's syndrome (trisomy 21 and partial trisomy 21) and the development of the early onset of neuropathological changes which are identical to Alzheimer's disease. Consequently, his research group is testing the hypothesis that the neuropathogenesis of Alzheimer's disease is related to the activity of a locus on the distal end of chromosome 21. Their initial strategy involves constructing a purified chromosome 21 genomic library. They are using familial pedigrees from patients with Alzheimer's disease and Down's syndrome to discover if there are linkages between these diseases. Perhaps the most newsworthy data concerning the pathology of Alzheimer's disease per se came from an un- scheduled presentation by Dr. Wischik (MRC, Cambridge, U.K.), who reported his very recent success in analyzing paired helical filaments from neurofibrillary tangles using electron microscopic techniques. In these studies paired hel- ical filaments were isolated from brains of Alzheimer's pa- tients and fragmented prior to electron microscopy. Wischik found that the paired fibers wound in a regularly periodic left-handed helix. Further, he reported that the fibers could be fragmented at essentially random points along the helix. On the basis of these data, he concluded that the paired helical filaments were composed of structurally homogene- ous units, approximately 3 nm high and 9-10 nm across. If this interpretation is correct, then it follows that a single age-related change, resulting in the manufacture of one ab- berant protein might account for the formation of these paired helical filaments. The critical question, of course, re- mains whether this hypothesized change in protein synthesis should be regarded as fundamental and causative to the neuronal degeneration and neurotransmitter loss associated with the disease, or whether it is a secondary effect of some other change that also accounts for the more global neuro- chemical and neuropathological deficits. A related question is the relationship between the sub- cortical neuronal degeneration (e.g., in nucleus basalis of Meynert--nbM) and cortical pathology of Alzheimer's dis- ease (e.g., neurofibrillary tangles, senile plaques) and the possible consequences for the clinical impairments associ- ated with the disease. Drs. D. Bowen (University of London, D. E. Schmechel (Duke University Medical Center, Durham NC) and P. Whitehouse (Johns Hopkins University School of Medicine, Baltimore, MD) reviewed the relevant clinical neurochemical and neuropathological data in a symposium devoted to this issue. It was generally agreed that it could be useful for purposes of diagnosis and treatment to distinguish between patients with focal cortical lesions and those with 133