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Monographs of fragrance chemicals and extracts that have caused contact allergy / allergic contact dermatitis
Published in Anton C. de Groot, Monographs in Contact Allergy, 2021
These patterns varied from time to time within patients depending on degree of exposure, treatment and chronicity. Continued exposure often culminated in the picture of chronic actinic dermatitis. Involved sites other than the face were the hands (74%), particularly the backs of the hands and finger webs (probably because of aftershave trickling from the palms between the fingers during application and from light-exposure), the arms (42%), the trunk (31%), the legs (26%), and the axillae (20%), due to deodorant usage (31).
Nanotechnology and Anti-Ageing Skin Care
Published in Dilip Ghosh, Pulok K. Mukherjee, Natural Medicines, 2019
B. Fibrich, I.A. Lambrechts, N. Lall
Extrinsic ageing, on the other hand, is dependent on external factors such as lifestyle (nutrition, smoking, sleeping positions and alcohol ingestion) and environmental stress (pollution and sun exposure; Ganesan and Choi 2016). This type of ageing is also often referred to as actinic or photo-ageing as ultraviolet (UV) radiation from the sun is the largest contributor. UV rays may either be classified as UV-A, -B, or -C, depending on their wavelength. The inability of UV-C rays to penetrate the ozone layer render them the least concern, however, UV-A rays are able to penetrate the epidermis, while UV-B rays penetrate the deeper dermis (Jung et al. 2014).
Phototherapy with Ultraviolet B
Published in Henry W. Lim, Nicholas A. Soter, Clinical Photomedicine, 2018
Serge A. Coopman, Robert S. Stern
Photoaging, in contrast to true chronologic aging, is defined as skin changes as a result of repeated ultraviolet exposure rather than due to passage of time alone. It is characterized clinically by coarseness, wrinkling, laxity, increased fragility, mottled pigmentation, telangiectases, and atrophic or fibrotic areas (90). Although little is known about the precise action spectrum for actinic degeneration of the skin, epidemiologic and experimental data implicate UVB portions of sunlight in photoaging (90). Patients treated with UVB for psoriasis may receive as many as 1,000 MEDs per year, approximately 10 times the typical UVB exposure for persons living in a temperate climate who usually work indoors. Controlled prospective studies focusing on actinic changes in patients treated with today’s conventional UVB sources are lacking, precisely because of the slowly progressive nature of these lesions, but a dose-dependent increase can certainly be expected. Since psoriasis often spares the face, shielding of this area can limit the cosmetic significance of actinic damage.
Comparing efficacy and safety of potassium hydroxide 5% solution with 5-fluorouracil cream in patients with actinic keratoses: a randomized controlled trial
Published in Journal of Dermatological Treatment, 2022
Ali Salehi Farid, Somayeh Niknam, Kheirollah Gholami, Soheil Tavakolpour, Amir Teimourpour, Maryam Daneshpazhooh, Ali Nili, Arghavan Azizpour, Maryam Nasimi, Hamidreza Mahmoudi
Major treatments for actinic keratosis (AK) include two types: destructive modalities such as curettage, and cryotherapy; and nondestructive agents including topical creams such as 5-fluorouracil (5-FU) cream 5% (1–5). Destructive modalities can be associated with different adverse effects such as dyspigmentation, bulla formation, infection, and scarring (6–11). 5-FU is approved by the U.S. Food and Drug Administration (FDA) for the treatment of AK (12,13). However, 5-FU is associated with erythema, crust formation, and bleeding; its effectiveness decreasing in the long run (14,15). Potassium hydroxide (KOH) is a keratolytic agent that is used in the treatment of skin lesions such as warts, molluscum contagiosum, and plantar callus (16–19). KOH is an effective, safe, and inexpensive drug that can easily dissolve keratin and penetrate skin due to its alkaline nature (20).
Influence of infrastructure material composition and microtopography on marine biofilm growth and photobiology
Published in Biofouling, 2021
Baptiste Vivier, Pascal Claquin, Christophe Lelong, Quentin Lesage, Mathias Peccate, Bastien Hamel, Marine Georges, Amel Bourguiba, Nassim Sebaibi, Mohamed Boutouil, Didier Goux, Jean-Claude Dauvin, Francis Orvain
Photosynthetic parameters were measured daily using the Imaging-PAM fluorometer (Walz, Germany). The IMAGING-PAM Chlorophyll Fluorometer was designed to investigate the two-dimensional heterogeneities of photosynthetic activity. Fluorescence measurements were carried out using the Maxi Version of Imaging-PAM Chlorophyll Fluorometer (Walz, Effeltrich, Germany) associated with a LED-Array Illumination Unit IMAG-MAX/L (44 high-power royal-blue (450 nm) LED-lamps) and a CCD Camera IMAG- K7 equipped with a zoom objective lens (640 × 480 pixel resolution). Measurements were performed at a fixed working distance of 18.5 cm. A 5-min dark adaptation period allowed oxidation of the electron acceptor pools before each measurement. The saturation pulse intensity was 4,500 µmol photons m−2 s−1 for 0.8 s at the surface of the sample and the measuring pulse frequency was 8 Hz. Rapid light curves were performed as follows: samples were exposed to eight incremental intensities of actinic light (E): 0, 21, 111, 281, 396, 531, 611 and 701 µmol photons m−2 s−1 with 30 s irradiance steps. Numerical values and fluorescence images were extracted using analytical software (Imaging Win; Walz). Auto-fluorescence of each structure was recorded before the experiment in order to apply a correction to FO.
Effects of topical piroxicam and sun filters in actinic keratosis evolution and field cancerization: a two-center, assessor-blinded, clinical, confocal microscopy and dermoscopy evaluation trial
Published in Current Medical Research and Opinion, 2019
Marina Agozzino, Teresa Russo, Chiara Franceschini, Sara Mazzilli, Virginia Garofalo, Elena Campione, Luca Bianchi, Massimo Milani, Giuseppe Argenziano
Actinic keratosis (AK) is considered an “in situ” non-melanoma skin cancer induced by ultraviolet chronic exposure1. In general, several lesions are present in the same subject2, increasing the risk of malignant transformation3. The concept of field cancerization refers to the development of multiple lesions which derive from preneoplastic changes due to a cumulative exposure to carcinogenic agents4. The combined treatment of AK lesions and field cancerization is considered the gold standard in this clinical setting5. In the pathogenesis of AK, an increased activity of cyclooxygenase (COX) enzymes (both COX-2 and COX-1), at the keratinocyte level, plays a relevant role6,7. Topical anti-inflammatory agents, like diclofenac, could improve the evolution of this kind of lesion8. A topical product containing piroxicam 0.8% and sun filters (50 SPF) (ACTX) has been shown to be very effective in reducing AK lesions9–12. Non-invasive tools like dermoscopy and reflectance confocal microscopy (RCM) are considered effective alternatives to biopsy for the characterization of actinic damage and field cancerization13. So far, no data are available regarding the effects of this product on skin modifications evaluated by RCM and dermoscopy at the target lesion sites and on field cancerization.