ABSTRACT
Polymorphous light eruption (PLE) is a common disorder characterized by a delayed, abnormal response to ultraviolet (UV) radiation, with a varied morphology of itching efflorescences on sun-exposed areas of the skin. Thirty-one PLE subjects were treated with either UVA (340-400 nm) or UVA and UVB (300-400 nm) phototherapy during spring 1987 (10 exposures to UV light). They were randomly allocated to these 2 groups. For subjects of the UVA group, the applied dose corresponded to their individual minimal tanning dose; for subjects of the UVA and UVB group it corresponded to approximately 3/4 of their individual minimal erythema dose. The sun protection effect was studied by a high dose of UVA (80-160 J/cm2; 340-440 nm) after the treatment period, by analysing the histidine content of the stratum corneum and the urocanic acid photoisomerization, and by evaluating the subjects' diaries. The patients were asked to expose their skin to sunlight at least 3 times after UV hardening in the following 2-10 weeks. The results of both the UVA provocation and of the natural sun exposure confirmed the success of UV hardening without the occurrence of severe side effects. The content of histidine and of its metabolite urocanic acid in stratum corneum was significantly increased during the treatment. These data are interpreted to be biochemical markers for improved sun protection.
Subject(s)
Photosensitivity Disorders/prevention & control , Ultraviolet Therapy , Female , Histidine/analysis , Histidine/metabolism , Humans , Photosensitivity Disorders/metabolism , Skin/metabolism , Skin Pigmentation/radiation effects , Ultraviolet Therapy/methods , Urocanic Acid/analysisABSTRACT
The percutaneous absorption of indomethacin in 0.5 % or 1 % solution or 1 % gel at a dose of 50 mg or 100 mg indomethacin was compared in a randomized complete block design in seven healthy volunteers. The formulations were applied over an area of 12 dm(2) under an 8 h occlusion dressing. In addition, in the same volunteers the plasma concentration curves were determined after a single oral dose of 50 mg indomethacin. Indomethacin and some of its metabolites were determined with modified, existing assays using HPLC-fluorescence or gas chromatography-mass spectrometry. On the basis of a newly developed method, it was possible to separate and quantify O-desmethylindomethacin and N-deschlorobenzoyl-O-desmethylin-domethacin. After cutaneous administration of the two drug formulations, peak indomethacin plasma concentration of 95 ng/ml and 130 ng/ml were found between 4 and 8 h; the cutaneous bioavailability was approximately 20 % of the oral dose, as judged by comparing the areas under the plasma concentration time curves (AUC) and the amount of metabolites excreted into the urine. Percutaneous absorption did not change the metabolic pattern in the urine that is obtained after oral administration.
Subject(s)
Pulse/radiation effects , Reaction Time/radiation effects , Ultraviolet Rays , Adult , Elasticity , Humans , Male , Physical Exertion , Posture , Time FactorsSubject(s)
Lymphoma/etiology , Neoplasms, Radiation-Induced/etiology , Respiratory Tract Neoplasms/etiology , Ultraviolet Rays/adverse effects , Animals , Female , Melanoma/radiotherapy , Mice , Neoplasm Transplantation , Neoplasms, Experimental/radiotherapy , Temperature , Time Factors , Ultraviolet TherapyABSTRACT
The influence of chronic exposure to defined emission spectra within the natural UV global range on the skin of the NMRI-mouse was studied. It was shown that after a period of 15 months under suberythemogenic conditions neither carcinomas of skin nor elastic or collagenous tissue alterations were developed.
