The use of porphyrins for localization and photodynamic therapy of neoplastic disease has been the topic of several international symposia, reviews and books during the preceeding five years. The literature on this topic has continued to grow, as have numbers of presentations at national and international meetings relating to photobiology, chemistry, and lasers. In this volume, it is the intention of the editor to provide both information on current research projects, and detailed methodology used in such investigations. A bibliography on the subjects of porphyrin localization and therapy is included. The manuscripts contained in this volume are based on reports given at a Porphyrin Photosensitization Workshop which was held in Philadel phia, July 6-7, 1984. This Workshop was supported by NIH grant CA 36746, together with funds from the Fogarty International Center. Authors were requested to update their contributions to provide a summary of progress to mid 1985. Manuscripts containing material not presented in Philadelphia are also included, notably a series of articles describ ing current clinical and pre-clinical results from China. Since the Philadelphia Workshop, a meeting was held in Alghero, Sardinia (May, 1985), and additional conferences are now being planned; this attests to the continued interest in photodynamic therapy involving porphyrin photo sensitization.

The first edition of The Science of Photobiology was published in 1977, and was the first textbook to cover all of the major areas of photobiology. The science of photobiology is currently divided into 14 subspecialty areas by the American Society for Photobiology. In this edition, however, the topics of phototechnology and spectroscopy have been com bined in a new chapter entitled "Photophysics." The other subspecialty areas remain the same, i.e., Photochemistry, Photosensitization, UV Radiation Effects, Environmental Photobiology, Photomedicine, Circadian Rhythms, Extraretinal Photoreception, Vision, Photomorphogenesis, Photomovement, Photosynthesis, and Bioluminescence. This book has been written as a textbook to introduce the science of photobiology to advanced undergraduate and graduate students. The chapters are written to provide a broad overview of each topic. They are designed to contain the amount of information that might be presented in a one-to two-hour general lecture. The references are not meant to be exhaustive, but key references are included to give students an entry into the literature. Frequently a more recent reference that reviews the literature will be cited rather than the first paper by the author making the original discovery. The chapters are not meant to be a repository of facts for research workers in the field, but rather are concerned with demon strating the importance of each specialty area of photobiology, and documenting its relevance to current and/or future problems of man.

In recent years the field of contact dermatitis has increased greatly in importance in dermatology. The variety of exogenous, environmental ly caused dermatoses has undoubtedly expanded over the past few de cades with the increasing number of potentially toxic chemicals, the changes in lifestyle, and the greater life expectancy in industrialized societies. The value of international cooperation in this field has long been realized and acted upon by the International Contact Dermatitis Re search Group (ICDRG). By 1975 the international journal Contact Dermatitis had been founded under the editorship of C. D. Calnan. Thanks largely to the ICDRG and Contact Dermatitis, there were, by 1986, enough additional dermatologists and scientists with a special interest in this area to form the European Environmental and Contact Dermatitis Research Group (EECDRG). Within 2 years they had in stituted the European Society of Contact Dermatitis (ESCD) as an in ternational forum for researchers in the field. The EECDRG decided to hold a symposium in Heidelberg in May 1988, an initiative supported by the ICDRG, and on this occasion the new ESCD held its inaugural session. The Society already has over 200 members and most national contact dermatitis research groups in Europe are already represented; new members are of course welcome. Subgroups and working committees have been formed to address var ious topics including the standardization of patch testing, photoder matology, and bioengineering.

Radiation induces a variety of chemical processes in biological tissues. This volume is a synthesis of up-to-the-minute reviews on such photochemical and photobiological sensitized reactions with particular relevance to photomedicine. The first part gives a description of experimental techniques for the study of the primary processes after radiation absorption by biological systems. It is followed by chapters on singlet oxygen and photomedicine, considering both phototherapy and photochemotherapy. These sections also discuss the next generation of potential photosensitizing drugs.

This two-volume text provides a summary of studies relating to the use of photosensitizing agents in the diagnosis and therapy of cancer. This interesting work describes synthesis of new sensitizers, photochemical and photobiological properties of dyes currently used for photodynamic therapy, plus those being examined with a view toward providing therapeutic advantages. It contains results and methodology from leading experts on the use of porphyrins and other photosensitizers for detection of neoplastic disease and for photodynamic therapy of neoplastic disease. The volumes focus on the major clinical and pre-clinical research groups. They also include an appended bibliography which lists all pertinent publications in this field. This easy-to-understand book is written for all workers in the field of photodynamic therapy and provides an introduction to those beginning research on some aspect of tumor photosensitization.

Certain organic compounds can become toxic to biological tissue when activated by light. Many medical applications of this effect have been studied over the past twenty years, and This symposium brings together chemists, biologists, and clinicians to discuss the basic chemistry of the sensitizing compounds, their biological effects, and clinical applications in treatments of various cancers and skin disorders.