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Applications of PLA/Cellulose Composites
Published in Jyotishkumar Parameswaranpillai, Suchart Siengchin, Nisa V. Salim, Jinu Jacob George, Aiswarya Poulose, Polylactic Acid-Based Nanocellulose and Cellulose Composites, 2022
Exposure to UV radiation from the sun can cause photoaging, photo-carcinogenesis, and photo-immunosuppression that can result in skin damage and facial aging. Early aging is one of the commonest problems people face with symptoms such as the appearance of wrinkles, fine lines, and skin pigmentation (Uitto, 1997). With the evolution of cosmetics, the lives of people suffering from early aging got transformed. Anti-aging creams are widely used by people to combat skin aging and other related problems. Most cosmetic formulations contain metal oxide nanoparticles to provide immediate anti-aging effects (Raj et al., 2012). But these creams are often linked with the risk of toxicity concerns. Nanocellulose is one of the promising biomaterials that can be included in cosmetic products as an alternative to the use of metal oxide nanoparticles.
Ozone depletion and ultraviolet radiation
Published in Abhishek Tiwary, Jeremy Colls, Air Pollution, 2017
Chronic responses to UV include skin photoageing and skin cancer. First, long-term exposure to high UV fluxes leaves skin dry, wrinkled and leathery. This is mainly a cosmetic problem, but the change in skin texture can lead to chronic cracking and infection. Another chronic response is dilated blood vessels, giving the skin an inflamed appearance. Solar keratoses are small scaly lesions, which are considered to be premalignant and which may progress into squamous cell carcinoma, although this is rare. More importantly, DNA is one of the strongest UVA chromophores and genotoxic responses are to be expected.
Air pollution impacts on ozone
Published in Abhishek Tiwary, Ian Williams, Air Pollution, 2018
Chronic responses to UV include skin photoageing and skin cancer. First, long term exposure to high UV fluxes leaves skin dry, wrinkled and leathery. This is mainly a cosmetic problem, but the change in skin texture can lead to chronic cracking and infection. Another chronic response is dilated blood vessels, giving the skin an inflamed appearance. Solar keratoses are small scaly lesions, which are considered to be premalignant and which may progress into squamous cell carcinoma, although this is rare. More importantly, DNA is one of the strongest UVA chromophores and genotoxic responses are to be expected. The carcinomas are divided into melanomas and non-melanomas. For our purposes, a melanoma is a malignant tumour that arises from melanocytes – the cells of the skin that produce melanin. It is the least treatable, and hence the most important, type of skin cancer. Non-melanoma cancers are divided into basal cell carcinomas (BCCs, which account for about 75% of cases) and squamous cell carcinomas (SCCs). Basal cell carcinomas are raised translucent nodules, which develop slowly on the face, neck and head. Squamous cell carcinomas appear as persistent red crusted lesions on sun-exposed skin. Chronic over-exposure increases the incidence of both melanoma and non-melanoma skin cancers. Skin carcinomas are already the most common human malignancies. Multifactorial analysis has shown that age and UV exposure are the two most important factors in the epidemiology of the carcinomas, with the risk being expressed as a power law of the form: Risk=(annualUVdose)a(age)b
Recapitulate genistein for topical applications including nanotechnology delivery
Published in Inorganic and Nano-Metal Chemistry, 2022
Afroz Jahan, Juber Akhtar, Neha Jaiswal, Asad Ali, Usama Ahmad
Several variables have been linked to skin aging, including genetics, environmental exposure (UV radiation, xenobiotics, and mechanical stress), hormonal changes, and metabolic processes. Almost every aspect influenced changes in skin structure, function, and appearance. However, it has been widely acknowledged that UV radiation from the sun is unquestionably the single most important cause of skin aging. Photo-aging occurs when photodamage is superimposed over basically developed skin, causing premature aging. The membrane (skin) suffers this specific damage as a result of repeated and extended exposure to UV radiation. Clinically, the skin becomes rough when the epidermis stiffens first, followed by thinning of the dermis. Sallowness with wrinkles, laxity, uneven hyperpigmentation, lentigines and telangiectasis are all signs of photoaging.[45]
Bystander effect of ultraviolet A radiation protects A375 melanoma cells by induction of antioxidant defense
Published in Journal of Environmental Science and Health, Part C, 2022
Exposure to ultraviolet A (UVA) radiation from the sun is the most common and ubiquitous environmental hazard. The stratosphere absorbs solar UVC (200–280 nm) radiation, while UVA (315–400 nm) comprises 95% of the solar UV radiation reaching the earth and UVB (280–315 nm) accounts for the remaining 5%.1 Exposure to solar UV radiation has been associated with an increase in the risk of photoaging and skin cancer.2 The health consequences of exposure to each of the three ranges of the UV spectra differ because of the difference in their mechanisms of photobiological interactions.3 Due to the greater penetrability of UVA through the atmosphere, the potential human health hazards from this range of radiation should be evaluated more thoroughly.4 UVA triggers the formation of short-lived reactive oxygen species (ROS) to generate 8-oxo-7,8-dihydro-2′-deoxyguanosine (8-oxo-dG), leading to G→T transversions in DNA.2 Apart from DNA, ROS generated in cells on exposure to UVA causes oxidative damage to proteins and lipids.5 UVA has a direct melanomagenic effect in animals.2,6