Arch Dermatol
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Epidermolysis bullosa acquisita is a subepidermal bullous disease characterized by IgG autoantibodies directed against type VII collagen in anchoring fibrils. These autoantibodies are believed to play an important role in the pathogenesis of sub-lamina densa blister formation in this disease. ⋯ Acquired autoimmunity to type VII collagen in patients with epidermolysis bullosa acquisita may result in a clinical phenotype closely resembling that observed in patients with dystrophic epidermolysis bullosa. Passive transfer of purified IgG autoantibodies from a patient with severe epidermolysis bullosa acquisita to BALB/c mice produces histologic and immunopathologic alterations consistent with those seen in patients with this disease.
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Randomized Controlled Trial Clinical Trial
High sun protection factor sunscreens in the suppression of actinic neoplasia.
A controlled trial was undertaken from December 1987 to December 1990 to test the hypothesis that a strong sunscreen can reduce the number of cancerous and precancerous skin lesions. Candidates were selected from a high-risk population attending either a university- or Veterans Affairs-based dermatology practice in Lubbock, Tex, for a prospective, double-blind, controlled trial of daily application of sunscreen vs placebo over a 2-year period. Participants were asked to volunteer if they had demonstrated premalignant changes (actinic keratoses) or nonmelanoma skin cancer (basal cell carcinoma or squamous cell carcinoma), had continuing sun exposure, and were not using sunscreen on a regular basis. Fifty-three volunteers were initially enrolled in the study, and 37 came for the final 24-month visit. ⋯ The regular use of sunscreens can significantly reduce cutaneous neoplasia, as indicated by its suppression of precancerous lesions. A longer and/or larger study would be necessary to demonstrate an effect on malignant lesions.
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Basal cell carcinoma (BCC) of the skin is the most common neoplasm in white populations, and solar radiation is generally accepted to be the dominant environmental risk factor for this disease. However, little information is available on the nature of the relationship between BCC and sunlight. The purpose of this study was to evaluate the nature of the relationship between sunlight exposure, pigmentary factors, and BCC of the skin. A population-based case-control study of 226 male patients with BCC diagnosed from January 1, 1983, through December 31, 1984, and 406 randomly selected male control subjects was conducted in Alberta, Canada. The study was conducted using a standardized questionnaire, administered in person by trained interviewers. Data were analyzed using conditional logistic regression methods. ⋯ The lack of association between cumulative sun exposure and BCC contradicts conventional wisdom about the cause of this tumor, and the increased risk with sun exposure at age 0 to 19 years suggests that childhood and adolescence may be critical periods for establishing adult risk for BCC.
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Multicenter Study
Incidence and distribution of subepidermal autoimmune bullous skin diseases in three French regions. Bullous Diseases French Study Group.
The incidence and distribution of autoimmune subepidermal bullous diseases were estimated from prospective data (including immunoelectron microscopy) obtained from 100 cases during a mean period of 35 months in three university dermatologic centers in Amiens, Limoges, and Tours, France, that correspond to a cumulative reference population of 3.55 x 10(6). ⋯ Our prospective study is the first assessing the incidence and distribution of autoimmune subepidermal bullous disorders that systematically included immunoelectron microscopic data. Our estimated incidence of bullous pemphigoid (seven new cases per million people per year) is large enough to establish bullous pemphigoid as the major autoimmune subepidermal bullous disease for the purpose of therapeutic trials. On the contrary, all other disorders, particularly epidermolysis bullosa acquisita (estimated annual incidence, 0.17 to 0.26 per million people), were very rare and reflect the paucity of patients available for short-term clinical studies in France.