1. Department of Dermatology, Kligman Laboratories, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
2. Screening and Protein Sciences, Merck & Company, North Wales, PA 19454, USA.
3. Department of Pharmacology and the Institute for Translational Medicine and Therapeutics, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
4. Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD 21231, USA.
5. Department of Oral and Maxillofacial Surgery, University of Pennsylvania School of Medicine, Philadelphia, PA 19104, USA.
6. Gillette Corporation, Foxborough, MA 02035, USA.
7. University of Texas M. D. Anderson Cancer Center, Science Park–Research Division, Smithville, TX 78957, USA.