Home About us Contact
|
Home About us Contact | ||
|
|
||
Artificial Sources (artificial + source)
Selected AbstractsTanning and Cutaneous MalignancyDERMATOLOGIC SURGERY, Issue 4 2008SHERRIF F. IBRAHIM MD BACKGROUND Exposure to ultraviolet radiation (UVR) results in a darkening of the skin known as tanning. Recently, it has been shown that tanning is a response to UVR-induced DNA damage and represents the skin's efforts to protect itself against further injury. Despite the link between UVR and cutaneous malignancy, people continue to pursue tanning from natural and artificial sources. This trend is reflected in the exponential rise in skin cancer incidence. OBJECTIVE The objective of this study was to review our current understanding of the factors controlling the tanning response and the relationship to cutaneous carcinogenesis, as well as the impact that the multibillion dollar tanning industry has had on the practice of dermatology. MATERIALS AND METHODS Extensive literature review was conducted in subjects related to tanning and the relationship to cutaneous malignancy. RESULTS Our knowledge of tanning and its effects on the skin has increased tremendously. It is clear that tanning contributes to the development of skin cancer. Despite this information, the incidence of skin cancer continues to increase exponentially. CONCLUSIONS Skin cancer poses a major public health concern and tanning remains the most modifiable risk factor in its etiology. Social, economic, and legislative issues have become tightly intertwined with the complex nature of human behavior in the continued pursuit of an activity that clearly has detrimental effects on one's health. [source] A11. UV-related skin hazards: allergic photodermatitisJOURNAL OF COSMETIC DERMATOLOGY, Issue 2 2002Paolo Pigatto Cases of dermatitis induced by exposure to ultra-violet radiation are increasingly encountered in clinical practice, with contact allergic photodermatitis accounting for about 10% of cases. Its frequency seems to be increasing, not only as a result of the increased use of cosmetic products and contact with some of the materials of working processes, but above all because of the greater exposure to both natural and artificial sources of UV radiation. Many substances have been defined ,photo-allergising' but their exact prevalence has varied over the years with the introduction and use of new substances in cosmetics and pharmaceutical products. For these, and other reasons, there are few studies concerning the prevalence and incidence of contact allergic photodermatitis in Italy. A total of 2160 patients with clinical histories suggestive of photoallergic contact dermatitis were seen. All patients underwent photopatch tests with haptens proposed by the Gruppo Italiano Ricerca Dermatiti da Contatto plus other substances suggested by each patient's history. 518 patients (24%) were positive to at least one test substance of the standard series or to added substances. Typical photoallergic reactions were seen in 423 subjects, representing 19.5% of the total population. Topical drugs are the substances most frequently involved in photodermatitis. The incidence in our population was about equal for antimicrobial agents, additives to fragrances, and fragrances themselves. Other allergens frequently found were sun screening agents which were the second group of haptens with clear-cut relevance. [source] Standard Ultraviolet Daylight for Nonextreme Exposure Conditions,PHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 4 2005François J. Christiaens ABSTRACT The skin is exposed to ultraviolet radiation (UVR) from natural or artificial sources on a daily basis. The effects of chronic low dose exposure merit investigation, even when these effects are neither conspicuous nor clinically assessable. The purpose of the present study was to define a relative spectral UV irradiance that is representative of frequent nonextreme sun exposure conditions and therefore more appropriate for studies of the long-term and daily effects of solar UV on the skin. Solar spectral UV irradiance values were calculated for different dates and locations by using a radiative transfer model. The spectral irradiance values obtained when the solar elevation is lower than 45° were averaged. An important feature is the dUVA (320,400 nm) to dUVB (290,320 nm) irradiance values ratio, which was found to be 27.3 for the overall average. When the months corresponding to extreme irradiance values (low or high) were excluded from the calculations, the dUVA to dUVB ratio ranged from 27.2 to 27.5. The mean spectral irradiance of the model presented here represents environmental UV exposure conditions and can be used both as a standard to investigate the biological effects of a nonextreme UVR and to assess the effectiveness of products for daily skin protection. [source] Cutaneous effects of infrared radiation: from clinical observations to molecular response mechanismsPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 5 2003Stefan M. Schieke Human skin is exposed to infrared (IR) radiation (760 nm,1 mm) from natural as well as artificial sources that are increasingly used for cosmetic or medical purposes. Epidemiological data and clinical observations, however, indicate that IR radiation cannot be considered as totally innocuous to human skin. In particular, IR radiation, similar to ultraviolet radiation, seems to be involved in photoaging and potentially also in photocarcinogenesis. The molecular consequences resulting from IR exposure are virtually unknown. Recent studies, however, have begun to shed light on the basic molecular processes such as cellular signal transduction and gene expression triggered by exposure to IR radiation. In response to IR irradiation, mitogen-activated protein kinase signaling pathways were activated mediating the upregulation of matrix metalloproteinase-1 expression. This previously unrecognized molecular ,IR response' shows that IR radiation is capable of specifically interfering with cellular functions and provides a molecular basis for biological effects of IR on human skin. [source] | ||||||||||