Acta dermato-venereologica. Supplementum最新文献

Recent research has demonstrated the activity of calcipotriol, effective as a potent inhibitor of cellular proliferation and known to increase differentiation in a number of cell lines in the topical treatment of psoriasis. Vit D3 receptors are expressed in keratinocytes and vascular endothelial cells. We studied the alterations in basal keratinocytes (stem cells or anchoring cells) and endothelial cell modification in 6 patients with psoriasis treated with calcipotriol ointment twice a day for 4 weeks. The samples were embedded in Epon resin for thin section and ultrathin section examination by electron microscopy. A normal pattern of distribution of the two different types of basal keratinocytes was observed before treatment. After treatment, only anchoring cells were detected. The alterations of endothelial cells in capillary loop disappeared after treatment, presenting normal aspects. Our morphological findings suggest that calcipotriol is therapeutically effective, due principally to an inhibition of cellular proliferation.

The aim of the present study was to investigate the distribution of Langerhans cells and T cells in the lesions and also the phenotypic expression of markers of activation on lesional T cells and keratinocytes, before and after 2 weeks of topical treatment of 7 psoriatic patients with calcipotriol. Before treatment, the infiltrate was composed mainly of T cells and there was decreased expression of CD1 on the intra-epidermal Langerhans cells. ICAM-1 and EGF receptor were present throughout the epidermis, but keratinocytes expressing Transferrin receptor were detected only in the basal layer. After 14 days of calcipotriol therapy, there were significantly fewer CD4T cells in the dermis and an increased number of intraepidermal CD1 + Langerhans cells. ICAM-1 expression on lesional keratinocytes was reduced in all patients, but the expression of EGF receptor was decreased in 3 patients only, and Transferrin receptor expression on keratinocytes had not changed. All these changes were concurrent with moderate clinical improvement of the lesions. The results suggest that in the early stages of the clinical response to calcipotriol there is an immunomodulating effect of the drug associated with variable decreases in keratinocyte expression of markers of activation.

Bioengineering techniques for examination of the skin, measuring principles and sources of error relative to technique, study design, measuring conditions and variability related to test subjects and preconditioning are reviewed. Principles of validation and standard operating procedures (SOP) are discussed, including guidelines for measurement of transepidermal water loss (TEWL) and laser Doppler cutaneous blood flow. Today typical errors are not related to a measuring device but to the way it is used.

The aim of this study was to show degree and pattern of hand eczema in affected hairdressers (n = 69), compared with a control group of teachers (n = 19). Both groups consisted of employees having eczema, confirmed by the visit of a doctor at the working place. The mean age for the affected hairdressers was 27 years (range: 17-63) and for the teachers 43 years (range: 27-57). The mean duration of employment was 96 months for the hairdressers (range: 2-552) and 182 months for the teachers (range: 25-336). The localization of eczematous lesions, presence of efflorescenses and extent of skin affection were recorded by constructing scores for these variables. The mean number of localizations was significantly higher in hairdressers than in teachers; this was caused by greater affection of fingers in hairdressers compared to teachers. Seventy-five percent of the hairdressers and 79% of the teachers had only modest or very moderate erythema. Fourteen percent and 5%, respectively, had vesicular dermatitis. The right upper limb was most affected in both hairdressers and teachers. Three subgroups of hairdressers were considered: hairdressers with atopic dermatitis, those with only atopic mucosal symptoms and those without atopic symptoms. No significant differences were found between these groups, except a significant higher finger involvement in atopics compared to non-atopics.

Gäfvert, E. 1994. Allergenic components in modified and unmodified rosin. Chemical characterization and studies of allergenic activity. Acta Dermato-Venereologica. Suppl. 184. 36pp. Uppsala. Unmodified rosin (colophony) is a well-known cause of contact allergy (delayed type hypersensitivity). Rosin is obtained from coniferous trees and consists mainly of diterpenoid resin acids. Most rosin used in technical products is chemically modified. In the common modification of rosin with maleic anhydride, the major product formed is maleopimaric acid (MPA). MPA was identified in experimental sensitization studies as a potent contact allergen. MPA is also formed when rosin is modified with fumaric acid at high temperature and with prolonged heating. The amounts of MPA in technical quality rosins modified with maleic anhydride or fumaric acid might be enough to sensitize individuals handling these rosins. The major product of the modification of rosin with fumaric acid, fumaropimaric acid (FPA), did not elicit any reactions in the animals tested. In another common rosin modification, glycerol esterification, the major product formed was identified as glyceryl triabietate (GTA). In an experimental sensitization study none of the animals reacted to GTA. However, a minor product formed, glyceryl 1-monoabietate (GMA) showed sensitizing capacity. The presence of new contact allergens due to the modification, together with remaining unmodified material, contributes to the risk of developing allergy from contact with these types of rosin. A new main contact allergen in unmodified rosin was identified; 13,14(beta)-epoxyabietic acid. The allergenicity of this epoxide was comparable to that of an earlier identified rosin allergen, 15-hydroperoxyabietic acid (15-HPA). The allergens were detected as their methyl esters. Experimental sensitization and cross-reactivity of oxidation products of resin acids were studied. A pattern of cross-reactivity was observed which indicates that the hydroperoxide of abietic acid (15-HPA) may react to form a complete antigen via two different routes. One route seems to be via the formation of epoxides which then react with skin protein to form the complete antigen, and the other, via radical formation due to cleavage of the peroxide bond. The radical formed may then react with skin protein, so producing the complete antigen. Few other studies have shown results indicating the formation of several antigens from one hapten.