TRICHOTHIODYSTROPHY WITHOUT PHOTOSENSITIVITY - BIOCHEMICAL, ULTRASTRUCTURAL AND DNA-REPAIR STUDIES

A case of trichothiodystrophy (TTD) without photosensitivity is reported in an 8-year-old girl. Electron microscopic (EM) examination of the keratinocytes showed fibrillary bundles in the cytoplasm thinner and less electron dense than those of the normal cells and large membrane-bound vacuoles filled with granular-filamentous material. These findings could indicate a disturbance in the protein metabolism in tissues of ectodermal origin, explaining also the functional abnormalities of the central nervous system in TTD patients. The results of cellular DNA repair studies after UV irradiation in cultured fibroblasts showed normal levels of unscheduled DNA synthesis. This finding indicates that UV hypersensitivity is not constantly present in TTD

Spotlight on adapalene.

BACKGROUND: In the field of dermatology, topical retinoids represent a mainstay in acne treatment. Adapalene is a naphthoic acid derivative showing some pharmacological activities similar to the regular retinoids. The drug is used singly or in combination for treating acne and a few other miscellaneous skin disorders. OBJECTIVE: To critically review the pharmacokinetic, pharmacologic aspects and clinical benefits and adverse effects associated with topical adapalene. METHOD: A systematic literature review was conducted primarily based on PubMed citations. RESULTS/CONCLUSIONS: Adapalene shares some biological activities in common with retinoic acid. However, it exhibits distinct physicochemical and binding properties for selective retinoic acid receptors. In acne, adapalene is expected to reduce comedogenesis, expel mature comedones and exert some anti-inflammatory effects. The drug is effective as monotherapy in mild comedonal acne and in combination with benzoyl peroxide for mild-to-moderate inflammatory acne. The safety profile of adapalene is good. Indeed, only discrete to moderate adverse events including erytheme, xerosis, itching and stinging may develop during the early treatment phase. Clinical experience has established that adapalene represents a valuable addition to the other current treatments for acne