Avril D. Woodhead

We discuss the role of sunlight, mostly ultraviolet light (UV), in the induction of nonmelanoma and melanoma skin cancer. Whilst the former seems to be correlated with accumulated exposure, the causation of melanoma is more complex, and may also involve the pattern of, and age at, exposure. The efficacy of sunscreens is debatable; while they protect against UVB wavelengths (290-320 nm), and so extend the time that may be spent in the sun before becoming sunburnt, their use may subject wearers to excessive exposure to UVA (320-400 nm) and visible light. Both epidemiological surveys and experiments with animal models suggest that UVA, and perhaps the visible, may induce melanomas. Although Japanese have a much lower incidence of skin cancer than Caucasians, the dramatic rise in skin cancer in Japanese-Americans in Hawaii exposed to high-intensity irradiation raises concerns. If the Japanese people adopt sun-seeking behavior, or should the levels of UV irradiation rise significantly through depletion of the ozone layer, then this could become an important health problem in future.

The Choice of Nonmammalian Models in Biomedical Studies. Protozoans as Models of Cellular Aging: The Cil-iates. Leeches: Annelids of Medical and Scientific Util-ity. Crustacean Urinary Bladder as a Model for Vertebrate Renal Proximal Tubule. Insect Models for Biomedical Re-search. Housefly Model for Organophosphate Poisoning. Fertilization in Ascidians. Sea Urchin Fertilization: A Versatile Model for Studying Signal Transduction, De-fenses Against Oxidant-Mediated Damage, and Extracellular Matrix Assembly. Elasmobranches (Sharks, Skates, and Rays) as Animal Models for Biomedical Research. Biomedi-cal Applications of Marine Animals. Nervous Control of Ventilation and Heart Rate in Elasmobranch Fish, A Model for the Study of the Central Neural Mechanisms Mediating Cardiorespiratory Interactions in Mammals. Use of Small Fish in Biomedical Research, with Special Reference to In-bred Strains of Medaka. Freshwater Fish in Research on Radiation Biology. The Goldfish Visual Pathway: Interme-diate Filament Proteins in Nerve Growth and Development. Amphibians: A Rich Source of Biological Diversity. Am-phibian Models in Endocrine Research. Reptile Models for Biomedical Research. Sulfydryl-Rich Hemoglobins in Rep-tiles: A Defense Against Reactive Oxygen Species. The Do-mestic Fowl as a Biomedical Research Animal. The Domestic Fowl as an Animal Model for Human Albinism. A Molecular, Evolutionary Perspective of Nonmammalian Models in Bio-logical Research. Ethical and Regulatory Considerations in the Use of Cold-Blooded Vertebrates in Biomedical Re-search. Index.