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Photoecological consequence of ozone holes are considered. Analysis of the total UV-radiation intensity and the short-wave edge of atmospheric transmittance depending on ozone content is presented. Characteristic times of some photodamages to skin and eyes have been estimated under ozone content reducing. A role of photosensitizers including drugs in phototoxical effects is discussed. Possible ways of photoprotection are considered.

A patient with a rare dermatosis, actinic reticuloid, is described. Differential diagnostic characteristics of this condition as against mycosis fungoides are presented, and rational therapy of such patients is discussed.

Mechanical removal of the horny layer immediately after UV irradiation of the skin did not result in development of erythema when irradiated in the minimal erythemal dose (MED). When a patient was irradiated in a dose of 2 MED, the intensity of erythema was drastically reduced. This leads to a conclusion that the metabolites accumulating on the surface of the skin and in the horny layer during their oxidation with UV light are capable of return diffusion into the skin where they act as erythema mediators. Simultaneous recording of lipid peroxidation and oxygen consumption in the removed horny layer has demonstrated the relationship between the intensity of oxidation processes in the horny layer and the UV irradiation dose.

By means of morphological methods the mechanisms of thanatogenesis were studied in 57 white mice after the hematoporphyrin derivative administration and xenon lamp radiation imitating the sun spectrum. In dependence of integrative doses of sensitized photoradiation and individual resistance of the organism there was observed immediate (hours), retained (days) and remote (weeks) death of animals. In the first two groups death came as a result of photocoagulation of plasma proteins and toxemic shock with liver, lung and brain injury, and in the third group--as a result of suppurative resorptive intoxication against the background of ulcerous skin necrosis.

Two patients with the plaque form of photodermatosis are described. Clinical manifestations of this condition are similar to those of discoid lupus erythematosus in appearance, but not to those of prurigo or eczema. The authors suggest that the term 'polymorphic photodermatosis' be used instead of 'solar prurigo' or 'solar eczema', representing, in their opinion, clinical variants of the same disease.

Examinations of 518 refinery workers have revealed photodermatoses in 106. The disease ran a benign course: chronic or subacute one, eventuating in hyperpigmentation and vascular maculae in the workers exposed to oil and oil products. The patients suffering from occupational photodermatoses develop immunologic shifts, i.e. reduced levels of T-cells, T-suppressors, elevated counts of B-cells and of serum immunoglobulins G and M.