The Role of Photoprotection in Optimizing the Treatment of Atopic Dermatitis

Funding: The journal's Rapid Service Fee was supported by ISDIN.Atopic dermatitis (AD) is a chronic inflammatory skin disease with an estimated prevalence of 10-15% in children and 2-10% in adults. Clinically, there is notable phenotypic variability driven by a complex interaction between genetics, immune function, and the environment. Impairment of the skin barrier plays a significant role in the pathogenesis of AD. The apparent beneficial effect of sunlight in patients with atopic eczema is questioned due to its capacity to disrupt the skin barrier and generate free radicals that can damage proteins, lipids, and DNA. The sum of the external factors that an individual is exposed to throughout their lifetime is termed the exposome. Environmental factors such as sun exposure, temperature, and humidity contribute to both AD flares and regional prevalence variation. Literature on photoprotection in atopic dermatitis is very scarce. The use of adequate sunscreens in atopic dermatitis can ensure the level of photoprotection required to prevent skin photoaging and skin cancer and to mitigate skin barrier dysfunction, decrease inflammation, and neutralize facial redness. Herein we discuss and review the role of UV radiation and the exposome in the etiology of AD, as well as the role of adequate photoprotection

Cnidome and Morphological Features of Pelagia noctiluca (Cnidaria : Scyphozoa) Throughout the Different Life Cycle Stages

Pelagia noctiluca is considered the most important jellyfish in the Mediterranean Sea, due to its abundance and the severity of its stings. Despite its importance in marine ecosystems and the health problems caused by its massive arrival in coastal areas, little is known about its early life stages and its cnidome has never been described. This study of the morphological and anatomical features throughout the life cycle identifies four early stages: two ephyra and two metaephyra stages. Ephyra stage 1, newly developed from a planula, has no velar canals, gastric filaments or nematocyst batteries. Ephyra stage 2, has velar canals, a cruciform-shaped manubrium and gastric filaments. Metaephyra stage 3 has eight tentacle buds and nematocyst clusters for the first time. Lastly, in metaephyra stage 4, the eight primary tentacles grow nearly simultaneously, with no secondary tentacles. Complete nematocyst battery patterns gradually develop throughout the later life stages. Four nematocyst types are identified: a-isorhiza, A-isorhiza, O-isorhiza and eurytele. Of these, a-isorhiza and eurytele are the most important throughout the entire life cycle, while A-isorhiza and O-isorhiza have a more important role in advanced stages. All nematocysts show a positive correlation between increasing capsule volumes and increasing body diameter of the ephyrae, metaephyrae, young medusae and adult medusae. In the early stages, the volumes of euryteles in the gastric filaments are larger than those in the exumbrella, indicating that the capsule volume is critical in the absence of marginal tentacles, specialized for feeding. This study provides updated information, the most extensive description to date, including high-resolution photographs and schematic drawings of all the developmental stages in the life cycle of P. noctiluca. Additionally, the first cnidome characterization is provided for each stage to facilitate accurate identification of this species when collected in the water column, and to raise awareness of the potential for human envenomation

Differing Effects of Vinegar on Pelagia noctiluca (Cnidaria: Scyphozoa) and Carybdea marsupialis (Cnidaria: Cubozoa) Stings - Implications for First Aid Protocols

Special issue Cnidarian Venom.-- 11 pages, 3 figures, 3 tables.-- Data Availability Statement: Data sharing not applicable. No new data were created or analyzed in this studyThe jellyfish species that inhabit the Mediterranean coastal waters are not lethal, but their stings can cause severe pain and systemic effects that pose a health risk to humans. Despite the frequent occurrence of jellyfish stings, currently no consensus exists among the scientific community regarding the most appropriate first-aid protocol. Over the years, several different rinse solutions have been proposed. Vinegar, or acetic acid, is one of the most established of these solutions, with efficacy data published. We investigated the effect of vinegar and seawater on the nematocyst discharge process in two species representative of the Mediterranean region: Pelagia noctiluca (Scyphozoa) and Carybdea marsupialis (Cubozoa), by means of (1) direct observation of nematocyst discharge on light microscopy (tentacle solution assay) and (2) quantification of hemolytic area (tentacle skin blood agarose assay). In both species, nematocyst discharge was not stimulated by seawater, which was classified as a neutral solution. In P. noctiluca, vinegar produced nematocyst discharge per se, but inhibited nematocyst discharge from C. marsupialis. These results suggest that the use of vinegar cannot be universally recommended. Whereas in case of a cubozoan C. marsupialis sting, the inhibitory effect of vinegar makes it the ideal rinse solution, in case of a scyphozoan P. noctiluca sting, vinegar application may be counterproductive, worsening the pain and discomfort of the stung areaThis research was mainly funded by ISDIN company (Barcelona, Spain) and with the collaboration of the CaixaResearch by “la Caixa” Foundation through the project “Repercusiones Clínicas y Socioeconómicas de las Medusas en el Mediterráneo” (RECLAIME).-- This work acknowledges the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S)Peer reviewe

Photoprotection of the Skin from Visible Light‒Induced Pigmentation: Current Testing Methods and Proposed Harmonization

Visible light (VL) can induce pigmentary alterations, especially in dark-skinned individuals, and exacerbate photodermatoses and pigmentary disorders. Currently, there is no standardized method for assessing sunscreen protection against VL. On the basis of a critical review of published in vitro and in vivo methods, a VL photoprotection assessment method based on pigmentation is proposed