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J. Soc. Cosmet. Chem., 38, 141-143 (March/April 1987) Abstracts The Annual Scientific Meetings and Seminars of the Society of Cosmetic Chemists are important venues for informing the participants about the state of the art and recent technical advances in the field of Cosmetic Science. To provide broader dissemination of that information, the Publi- cations Committee has decided to publish abstracts of technical presentations made at these Meetings and Seminars in the Journal.--The Editor. Society of Cosmetic Chemists Annual Scientific Seminar May 14-15, 1987 SESSION I The effect of aging on cutaneous barrier func- tion Kathleen V. Roskos, University of California San Francisco, Department of Pharmaceutical Chem- istry, 926 Medical Sciences, San Francisco, CA 94143 Despite much research into the mechanisms of cuta- neous aging and the identification of significant age-associated biological and biophysical changes within the skin, the effect of skin aging on the per- cutaneous absorption (PA) of drugs and other chem- icals has received minimal attention. We have made preliminary in viva measurements of PA in "old" subjects ()65 years) and have compared the results to published data obtained in "young" populations (18-35 years) (Feldman and Maibach, 1969 1970). Standard radiotracer methodology was em- ployed and PA was quantified from the urinary ex- cretion profiles of 14C label (corrected for incom- plete renal eliminations). Benzoic acid (BA), hydro- cortisone (HC), and testosterone (TST) have been studied. Penetration of BA and HC wvs signifi- cantly (p 0.05 and p 0.01, respectively) lower in aged subjects, whereas TST absorption was not distinguishable from the "young" controls. Thus, it appears that aging can affect PA in viva and that relatively hydrophilic drugs may be most sensitive. In addition, preliminary work utilizing transepi- dermal water loss (TEWL) will be presented. A noninvasive technique, TEWL measures the insen- sible loss of water across human skin and provides a useful means to assess barrier function. Living skin equivalent Eugene Bell, Ph.D., Organogenesis Inc., 83 Rogers Street, Cambridge, MA 02142 The Living Skin Equivalent (LSE) is being fabri- cated for two distinct classes of users. The first con- sists of individuals who require skin for replacement of their own damaged or diseased skin, and the second, of companies that must test the effects of their products on viable human skin. The LSE is an organ reconstituted from components normally present in skin. The dermis of the LSE is made up with human dermal fibroblasts, intercellular matrix proteins, and other molecules that surround dermal cells. The dermis is separated from the epidermis by a basal lamina that develops in vitro. The epidermis differentiates from human keratinocytes, forming a well-organized cuboidal basal layer. The latter gives rise to a multilayered stratified tissue covered by a completely keratinized stratum corneum. The LSE can be provided with functional melanocytes, it is biosynthetically active, and it remains viable in the incubator for long periods. Cell renewal revisited--Panacea or pariah? Peter Pugliese, M.D., Xienta Inc., Bern- ville, PA 19506 The basic mechanisms of cell division and prolifera- tion will be reviewed with emphasis on stimulation 141