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The science of ageing
Published in Michael Parker, Charlie James, Fundamentals for Cosmetic Practice, 2022
Free radical production is particularly important in the development of deep wrinkles through a process known as solar elastosis. Free radicals within the skin cause upregulation of the elastin promoter gene, which increases the production and storage of elastin within the outer dermal layer. Solar elastosis can be seen as a yellowish tinge to the skin with multiple deep crisscrossed wrinkles commonly demonstrated on the chest, neck and limbs. Further atrophic changes demonstrated in the skin are due to reactive oxygen species translocating glycosaminoglycans, such as hyaluronic acid within the dermal layer, and inadvertently modifying their primary disaccharide units. Glycosaminoglycans are usually found interspersed between collagen fibres, where their positive oncotic pressure draws in water to keep tissues hydrated. Free-radical damage to glycosaminoglycans means they are moved from collagen fibres in the dermis to elastic tissue in the superficial dermis. This movement of glycosaminoglycans means that collagen fibres become dehydrated and the skin loses fullness, further contributing to the appearance of older skin.
Skin damage from environmental hazards
Published in Ronald Marks, Richard Motley, Common Skin Diseases, 2019
Although UVA is 1000-fold less effective at causing erythema, there is a lot of it in sunshine and it does penetrate to the dermis. It is thought to play a role in causing the dermal degeneration known as solar elastosis, which is mainly responsible for the appearance of ageing as well as contributing to the cause of skin cancer. UVA is also the part of the spectrum mainly responsible for photosensitivity reactions.
A Two-Stage Immunocytochemical Method for Putative Estrogen Receptor Analysis
Published in Louis P. Pertschuk, Sin Hang Lee, Localization of Putative Steroid Receptors, 2019
Vincenzo Eusebi, Gianni Bussolati
We felt that an improvement of the existing techniques for assaying estrogen receptors was needed, at the time, in view of conflicting evidence in the literature concerning the lack of correlation between morphological and functional parameters of breast tumors. A correlation between high ER content and a low histological grade of malignancy had in fact been found by some workers,2,3 but denied by others.4-6 Several groups of workers found a positive correlation between ER positivity and the lobular type of invasive carcinoma,7-9 a finding not corroborated by other groups.2,3,10 Furthermore, while one group reported that five tubular carcinomas were all ER-negative,6 another group found that four out of six tubular carcinomas were ER-positive.11 Lastly, while a direct relationship between the degree of tumor elastosis and the presence of ER has been reported,12 other workers suggested, from a multivariate analysis, that tumor elastosis might be more closely related to patient age rather than to ER status per se.2
Melasma treatment: a systematic review
Published in Journal of Dermatological Treatment, 2022
Nicoleta Neagu, Claudio Conforti, Marina Agozzino, Giovanni Francesco Marangi, Silviu Horia Morariu, Giovanni Pellacani, Paolo Persichetti, Domenico Piccolo, Francesco Segreto, Iris Zalaudek, Caterina Dianzani
Wood’s lamp examination has been used to classify melasma based on the the depth of melanin in the skin: epidermal, typified by a light brown coloration, dermal, exhibiting a bluish gray color or mixed, seen in a dark brown shade (4). However, in vivo reflectance confocal microscopy showed a heterogenous distribution of melanophages, thus indicating that all melasma is ‘mixed’ (5). It is now thought that melasma is the result of a complex interaction between epidermal melanocytes, keratinocytes, dermal fibroblasts, mast cells, vascular endothelial cells, and hormonal, genetic, as well as UV influence (6). Histopathologically, melasma is characterized by solar elastosis, basement membrane disruption, increased vascularization and increased mast cell count, which strongly indicate that melasma should also be regarded as a photoaging skin disorder (7).
Fractional radiofrequency in the treatment of skin aging: an evidence-based treatment protocol
Published in Journal of Cosmetic and Laser Therapy, 2020
Ileana Afroditi Kleidona, Dimitrios Karypidis, Nicholas Lowe, Simon Myers, Ali Ghanem
Photoaging is one of the major concerns of patients seeking esthetic interventions. There is a complexity of clinical signs including wrinkles, elastosis, dryness, dyspigmentation and texture irregularities. Ideally, the optimal treatment option should demonstrate the reversal of all unwanted manifestations of photodamage. During the last decade, there has been a substantial increase in cosmetic interventions with a trend toward minimally invasive techniques (44). Fractional radiofrequency has attracted scientific and commercial interest as a possible superlative treatment for skin rejuvenation. In 2009, Hantash et al. developed a microneedle therapy device through which bipolar radiofrequency was introduced into the skin. In this way, he generated fractional radiofrequency thermal zones in the dermis. Using immunohistochemistry and PCR studies, he observed dermal remodeling with neocollagenesis and neoelastogenesis (45). Today, there are various commercially available devices with different specifications. The RF systems typically consist of a generator and a handheld applicator with electrodes. Some examples of microneedling RF systems are the Infini (Lutronic, Korea), the INTRAcel (Jeysis, Korea), the Scarlet (Viol, Korea) and the ePrime (Syneron-Candela, Israel). RF devices with electrode pins include the eMatrix and the MatrixRF (Syneron-Candela, Israel).
Bilaminar Mechanics of the Human Optic Nerve Sheath
Published in Current Eye Research, 2020
Andrew Shin, Joseph Park, Alan Le, Vadims Poukens, Joseph L. Demer
Due to limited length of ON tissues attached to the donated globes, it was not possible to determine if the mechanical properties of the ON sheath might vary according to distance along its entire length in the orbit. However, specimens avoided the sheath region immediately adjacent the sclera and were from a region of the sheath in which thickness appeared uniform on inspection. In general, younger people may have more compliant peripapillary tissues than older people because of age-related stiffening in sclera49-51 and Bruch’s membrane.52 Elastosis of the LC progresses with age,53-56 particularly people who have open angle glaucoma.40,57,58 Scanning laser ophthalmoscopy demonstrates that optic disc and peripapillary tissue deformation during adduction tethering is less in older than younger healthy subjects.59 Elastin density in the human ON sheath increases significantly with age.24 Although specimens in the current study lacked sufficient age variation to address this question, it would of course be important to determine the relative laminar effects of age-related elastosis on the ON sheath, as sheath elastosis with advancing has been proposed as a likely etiologic factor in primary open angle glaucoma without elevated IOP.3 The current study had a paucity of specimens available for concurrent biomechanical and anatomical study, limiting quantitative interpretation of anatomic-mechanical correlations. Future studies would benefit from performing such correlative studies in additional specimens with sufficiently long ONs, and preferably in donors both affected and unaffected by glaucoma.