China
Africa
Explore chapters and articles related to this topic
Rosmarinic Acid: A Boon in the Management of Cardiovascular Disease
Published in Mahfoozur Rahman, Sarwar Beg, Mazin A. Zamzami, Hani Choudhry, Aftab Ahmad, Khalid S. Alharbi, Biomarkers as Targeted Herbal Drug Discovery, 2022
Md. Adil Shaharyar, Mahfoozur Rahman, Kumar Anand, Chowdhury Mobaswar Hossain, Imran Kazmi, Sanmoy Karmakar
The UV radiation present in the solar spectrum generates ROS (reactive oxygen species) that imbalances the homeostasis of the skin by causing damage of DNA in the cell. The photoprotective activity of rosmarinic acid is exerted by the free radical scavenging activity. Rosmarinic acid erects its own defense wall by the stimulation of melanin synthesis and modulation of tyrosinase activity (Sanchez-Campillo et al., 2009).
Management of skin disease
Published in Ronald Marks, Richard Motley, Common Skin Diseases, 2019
Many patients with psoriasis and some with acne and atopic dermatitis improve in the summertime after being out in the sun. It is the ultraviolet portion of the solar spectrum (see p. 29) that seems to aid these patients, and artificial sources of ultraviolet radiation (UVR) are often used in treatment. Natural sunshine can also be used if the local weather conditions permit. Special ‘spas’ have been established at the Dead Sea in Israel, around the Black Sea and elsewhere.
Photoirritation (Phototoxicity) Testing in Humans
Published in Francis N. Marzulli, Howard I. Maibach, Dermatotoxicology Methods: The Laboratory Worker’s Vade Mecum, 2019
Francis N. Marzulli, Howard I. Maibach
A report by the Commision Internationale de l’Eclairage (CIE) states that a review of data suggests that the damage risk for UVR at 290 nm appears to be about 100 times higher than that at 320 nm. (McKinlay and Diffey, 1987). The damage risk at 320 nm is about 10 times that at 340 nm and about 100 times that at 400 nm. These findings resulted in a modification of one traditional term (UVA) employed by the photobiologist to describe portions of the solar spectrum that are accorded special biologic attention. Besides UVA (320–400 nm), UVB (280–320 nm), and UVC (< 280 nm) we now have UVA 1 (340–400 nm) and UVA2 (320–340 nm). Other values for UVA, UVB, and UVC are given by the Commision de l’Eclairage (1970).
Skin impacts from exposure to ultraviolet, visible, infrared, and artificial lights – a review
Published in Journal of Cosmetic and Laser Therapy, 2021
Juliana Yuka Furukawa, Renata Miliani Martinez, Ana Lucía Morocho-Jácome, Thalía Selene Castillo-Gómez, Vecxi Judith Pereda-Contreras, Catarina Rosado, Maria Valéria Robles Velasco, André Rolim Baby
Light is divided into different spectra, depending on the wavelength (λ, nm). Natural light comes from the sun – a source of cosmic energy, ultraviolet (UV), gamma, and X rays. The solar spectrum is complex and its biological effects on humans depend on the cells’ absorption capacity, generating secondary molecules, according to each portion of the spectrum. Once absorbed, these radiations trigger different cellular routes (1). The human organism responds to these different energy stimuli with the production of hormones, such as adrenocorticotrophic hormone (ACTH), and beta-endorphin, vitamin D, nitric oxide (NO), and carbon monoxide (CO) (2). In addition, they can lead to the production of reactive oxygen species (ROS), matrix metallopeptidases (MMPs), cascade inflammatory reactions and cytokines that can be negative for the organism (3).
Insights and controversies on sunscreen safety
Published in Critical Reviews in Toxicology, 2020
Juliana P. Paiva, Raiane R. Diniz, Alvaro C. Leitão, Lucio M. Cabral, Rodrigo S. Fortunato, Bianca A. M. C. Santos, Marcelo de Pádula
UVB is one of the major environmental carcinogen (Gruijl 2000) which may induce direct and indirect DNA damage in the presence and absence of absorbing compounds, thus it appears unreasonable to perform cell irradiation protocols underestimating UVB effects. It is worthy to bear in mind that to test the photoprotective or phototoxic effects of topical substances for pharmaceutical or cosmetic uses, it is indispensable to use a radiation source closest to the solar spectrum (Onoue and Tsuda 2006). In this sense, the most recommended irradiation source for phototoxicity assessment is the solar simulation with an emitted UV spectrum and exposure time equivalent to the environmental sunlight (Gocke et al. 2000). In addition, tropical countries spectra should be also considered since sunlight spectrum may largely differ according to the latitude. In this sense, Hossy et al. (2017) and Diniz et al. (2019) have proposed an SSL irradiation protocol equivalent with a 30-min exposition at 12:00 noon in Rio de Janeiro, Brazil, on a summer day (Hossy et al. 2017; Diniz et al. 2019).
Novel techniques to prevent apoptosis and improve regeneration in corneal endothelial cells
Published in Expert Review of Ophthalmology, 2020
The cornea is unavoidable to exposure to solar ultraviolet radiation in natural environments. Among them UVA (315–400 nm) is a high-energy photon radiation of the solar spectrum. Cornea absorbs about 35% of the light in the UVA range which penetrates all corneal layers including endothelium, transmits to the lens nucleus and has a strong damage potential in corneas resulting in many ocular diseases including photoconjunctivitis, pterygium, climatic droplet keratopathy, photokeratitis, and cataracts, owing to UVA-induced oxidation-related toxicity [31–37]. UVA-induced oxidation-related toxicity primarily arises from the photo-production of ROS that is mediated by UVA-excited endogenous chromophores through type I or II photosensitization reactions [32]. In type I, singlet oxygen reacts with lipids to create peroxides, or with other substrates to generate ROS. While, in type II, a chromophore is excited by light to a triplet state that leads to a direct electron or hydrogen exchange with a substrate to create ROS and disrupts reduction-oxidation homeostasis resulting in oxidative damage to proteins, cellular membranes and DNA, and subsequently apoptosis [32,38,39].