1,720,963 research outputs found
Self tanning.
No full textDihydroxyacetone (DHA), binding the amino terminal of epidermal proteins, imparts an orange-brown colour to the skin 3-10 h from the application. The degree of skin darkening is related to the DHA concentration, usually from 2.5 to 6.5%. The action mechanism of DHA involves the formation of so-called melanoids, chromophores generated in the upper layers of the stratum corneum. Besides the browning effect, useful for cosmetic purposes or for masking hypopigmented macules of vitiligo, DHA application protects the skin against long-wave ultraviolet (λ>320 nm) showing an UVA protection factor from 1.7 to 2.2, depending on its concentration. The DHA does not protect against UVB (λ<320 nm). DHA containing sunscreens are useful to prevent polymorphous light eruptions or erythropoietic protoporphyria and to give a tanned look to hair-skinned individuals avoiding harmful sun exposures
A case of chronic actinic dermatitis treated with topical tacrolimus
No full textIntroduction: The treatment of chronic actinic dermatitis (CAD), a sun-induced disorder characterized by a persistent eczematous eruption, involves photoprotective measures, topical corticosteroid therapy and, in more severe cases, systemic immunosuppression. The potential side effects of systemic immunosuppressant drugs prompted us to evaluate the efficacy of topical tacrolimus for treatment of CAD. Patient and treatment: A 58-year-old man with CAD, resistant to previous treatment with topical and systemic corticosteroids, oral cyclosporine and PUVA-photochemotherapy, was treated with tacrolimus ointment 0.1% once a day. Results: Tacrolimus ointment led to significant improvement of pruritus and severe eczematous skin lesions after 20 days of treatment. Conclusions: Tacrolimus shows a beneficial effect on CAD; this could be attributed to the fact that CAD is characterized by a lymphohistiocytic infiltrate producing a chronic eczema and that tacrolimus blocks the activation of lymphocytes and other immune system cells, also inhibiting the release of mediators from cutaneous mast cells and basophils
LONG-LASTING PIGMENTATION MORE THAN ITS INTENSITY IS A RELIABLE INDICATOR OF SKIN SUN RESISTANCE
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Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Long-lasting pigmentation more than its intensity is a reliable indicator of skin sun resistance
No full textBACKGROUND: The currently adopted method for predicting sun sensitivity is Fitzpatrick's classification which however is based on self-reported burning tendency and tanning ability. Objective: Determination of the individual UV susceptibility based on non-subjective parameters. METHOD: Minimal erythema dose (MED), intensity and duration of pigmentation on days 5, 9 and 16 following 1 MED and the levels of the melanin marker pyrrole-2,3,5-tricarboxylic acid (PTCA) were analysed in non-red-haired subjects (50, aged 20-46 years). RESULTS: Phenotype groups or phototypes showed a good correlation with PTCA yields and the persistence of pigmentation on day 16, but not with MED values. MED values did not show a significant correlation with PTCA yields. On the other hand, high values on day 16 were exhibited only by subjects having PTCA values higher than 200 ng/mg. CONCLUSIONS: Measurement persistence of pigmentation on day 16 represents a non-invasive and easy-to-perform method to evaluate photoprotection in those individuals escaping straightforward classification based on phenotype or anamnesis
Monitoraggio della quantità di ultravioletto B solare sull’Italia meridionale.
Full text linkObjective: aim of this study was been the evaluation of daily and monthly changes of solar short ultraviolet (UVB) in a central Mediterranean area (Naples city, 40.8623° North) from 1997-2002. Materials and methods: the measurements were automatically collected and expressed as physical units (mW/cm2) and biological units (Minimal Erythema Dose/hour = MED/h). The irradiance unit may be converted to UV Index (UVI) by the conversion factor: 1 [MED/h] = 2.3 on the UVI scale. These values were processed with a special software Solar Light IDL 2.0 that informed us about current UV dose, accumulated UV dose, current UVI, peak UVI, time until sunburn, expressed in mins. Moreover, we studied these parameters by means of a statistical data analyser software called SPSS version 10.0 to obtain information about average values in this last 5 years of measurements. Results: the results showed that: i) the sporadic peaks of maximal irradiance occurred in June; ii) the maximal value of the monthly mean irradiance was observed in June-July, while the minimal one in December-January; iii) the amount of solar UVB that reaches the ground and therefore our skin during the last 5 years has been unmodified. About 20-30% of total daily UVB is received during the interval of time between 60 mins both before and after midday in summer, with 75% between 9 am and 3 pm. In Naples during the summer, half an hour of midday sun exposure of the unacclimatized skin of Caucasian subjects is normally sufficient to result in a subsequent mild reddening of the skin. We report that in Naples the average UVB sunstroke is equal to about 2 MED/day in winter; 7 MED/day in spring and in autumn, 12 MED/day in summer. According to Diffey algorithm, in Naples annual MED is about 2600, and these values have been confirmed by our measurements (2676 MED in 1998, 2591 MED in 1999, 2724 MED in 2000, 2612 in 2001, 2634 in 2002). Conclusions: our results show that erythema could appear, in individuals with skin type II and III living in a touristic Mediterranean area, after about 30 mins of sun exposure, in July; ii) the sunburn risk is higher just during the months when skin hasn't yet acquired the natural defences to respond to the peak of UVB. This monitoring may give more information about photodermatitis, photocarcinogenesis and some preventative devices of exposure to sun rays
Tollerabilità e resistenza di guanti in cotone nella prevenzione o come coadiuvanti in terapia: studio su 44 soggetti
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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