Aged Skin: A Study by Light, Transmission Electron, and Scanning Electron Microscopy

The fine structural organization of the epidermis, dermal/epidermal junction, and dermis from an unexposed site (upper inner arm) of elderly people was compared with the organization of a similar region of young people. Despite an overall thinning of the epidermis and focal areas of cytologic atypia, the characteristic morphological markers associated with the keratinization process are not markedly altered in appearance or amount. A well-formed stratum corneum consisting of flattened, enucleated horny cells enveloped by a thickened membrane, and intracellular spaces filled with electron-dense material provide structural evidence that barrier ability is not compromised in senile skin.The dermal/epidermal changes in aged skin are marked and have significant physiologic implications. The major change is a relatively flat dermal/epidermal junction resulting from the retraction of the epidermal papillae as well as the microprojections of basal cells into the dermis. This flattening results in a more fragile epidermal/dermal interface and, consequently, the epidermis is less resistant to shearing forces. Retraction of the epidermal downgrowths (preferential sites of the putative epidermal stem cell) may also explain the loss in proliferative capacity associated with the aged epidermis.The three-dimensional arrangements of collagen and elastic fibers showed marked alterations with age. Both fibrous components appear more compact because of a decrease in spaces between the fibers. Collagen bundles appear to unravel, and the individual elastic fibers show signs of elastosis. These changes may contribute to the loss of resilience that is one of the salient features of senile skin. J Invest Dermatol 88:44s-51s, 198

Analysis of Erythemal UVB Dose Received Inside a Car in Valencia, Spain

"This is the peer reviewed version of the following article: Ysasi, Gonzalo Gurrea, Vicente Blanca Giménez, Juan Carlos Moreno, and María Antonia Serrano. 2018. Analysis of Erythemal UVB Dose Received Inside a Car in Valencia, Spain. Photochemistry and Photobiology 94 (2). Wiley: 390 97. doi:10.1111/php.12865, which has been published in final form at https://doi.org/10.1111/php.12865. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Self-Archiving."[EN] Continuous exposures to ultraviolet radiation can lead to harmful effects on human skin. Professional drivers may spend more than 8 h per day inside a vehicle. This study describes an analysis of the UVER (erythemal ultraviolet radiation) received by a driver and passenger inside a vehicle. A three-door Peugeot 206 was used for the study. VioSpor Blue Line dosimeters (with a response profile close to that of human skin) were used to measure the erythematic dose of UV radiation (able to produce erythema on human skin). Four dosimeters were placed in the driver¿s position and another four in the passenger¿s position. Daily irradiance was analyzed for a day in April using PMA radiometers. The measurements were obtained on relatively clear days from February to December 2009 between 9:30 A.M. and 3 P.M. Additionally, a prediction was made of the time required to produce an erythema on the driver¿s skin. UVER exposure, in some of the driver¿s positions, exceeds the Exposure Limits given by the International Commission on Non-Ionizing Radiation Protection (ICNIRP). Skin protection measures should be taken into account by professional drivers to prevent the harmful effects of UVER radiation.This work was carried out with financing from the Ministry of Economy and Competitiveness, Project CGL2010-15931/CLI, from the Generalitat Valenciana within the PROMETEO/2010/064 Project, and the Spanish Ministry of Science and Innovation, in the CGL200761813 Project.Gurrea-Ysasi, G.; Blanca Giménez, V.; Moreno, J.; Serrano, M. (2018). Analysis of Erythemal UVB Dose Received Inside a Car in Valencia, Spain. Photochemistry and Photobiology. 94(2):390-397. https://doi.org/10.1111/php.12865S390397942Ysasi, G. G., & Ribera, L. J. C. (2013). Analysis of Two Kinds of Tree as Physical Barriers Against Erythemal UVB Radiation Received. Photochemistry and Photobiology, 89(3), 724-729. doi:10.1111/php.12020Giménez, V. B., Ysasi, G. G., Moreno, J. C., & Serrano, M. A. (2015). Maximum Incident Erythemally Effective UV Exposure Received by Construction Workers, in Valencia, Spain. Photochemistry and Photobiology, 91(6), 1505-1509. doi:10.1111/php.12530Parisi, A. V., Sabburg, J., & Kimlin, M. G. (2004). Scattered and Filtered Solar UV Measurements. Advances in Global Change Research. doi:10.1007/978-94-015-1246-6Lavker, R. M., Gerberick, G. F., Veres, D., Irwin, C. J., & Kaidbey, K. H. (1995). Cumulative effects from repeated exposures to suberythemal doses of UVB and UVA in human skin. Journal of the American Academy of Dermatology, 32(1), 53-62. doi:10.1016/0190-9622(95)90184-1Lavker, R., & Kaidbey, K. (1997). The Spectral Dependence for UVA-Induced Cumulative Damage in Human Skin. Journal of Investigative Dermatology, 108(1), 17-21. doi:10.1111/1523-1747.ep12285613Lowe, N. J., Meyers, D. P., Wieder, J. M., Luftman, D., Borget, T., Lehman, M. D., … Scott, I. R. (1995). Low Doses of Repetitive Ultraviolet A Induce Morphologic Changes in Human Skin. Journal of Investigative Dermatology, 105(6), 739-743. doi:10.1111/1523-1747.ep12325517Serre, I., Cano, J. P., Picot, M.-C., Meynadier, J., & Meunier, L. (1997). Immunosuppression induced by acute solar-simulated ultraviolet exposure in humans: Prevention by a sunscreen with a sun protection factor of 15 and high UVA protection. Journal of the American Academy of Dermatology, 37(2), 187-194. doi:10.1016/s0190-9622(97)80123-5Reglamento (CE) 561/2006 DEL PARLAMENTO EUROPEO Y DEL CONSEJO de 15 de marzo de 2006GUIDELINES ON LIMITS OF EXPOSURE TO ULTRAVIOLET RADIATION OF WAVELENGTHS BETWEEN 180 nm AND 400 nm (INCOHERENT OPTICAL RADIATION). (2004). Health Physics, 87(2), 171-186. doi:10.1097/00004032-200408000-00006Commission Internationale de l'Eclairage 1999 Erythema Reference Action Spectrum and Standard Erythema dose. CIE S-007-1998Gies, P., & Wright, J. (2003). Measured Solar Ultraviolet Radiation Exposures of Outdoor Workers in Queensland in the Building and Construction Industry¶. Photochemistry and Photobiology, 78(4), 342. doi:10.1562/0031-8655(2003)0782.0.co;2Moehrle, M., & Garbe, C. (2000). Personal UV Dosimetry by Bacillus subtilis Spore Films. Dermatology, 200(1), 1-5. doi:10.1159/000018306CEAM, Centro de Estudios Ambientales del MediterráneoDuarte, I., Rotter, A., Malvestiti, A., & Silva, M. (2009). The role of glass as a barrier against the transmission of ultraviolet radiation: an experimental study. Photodermatology, Photoimmunology & Photomedicine, 25(4), 181-184. doi:10.1111/j.1600-0781.2009.00434.

The Use of Cultured Allogenic Keratinocyte Grafting in a Patient with Epidermolysis Bullosa Simplex

Epidermolysis bullosa (EB) is a rare genetic disease that is known for continuous skin blistering caused by minor trauma. The skin blisters and bullae that develop often cause skin defects. There is no definitive treatment for EB, only symptomatic relief. We report our experience with cultured allogenic keratinocyte grafting in a newborn patient with EB simplex who had unhealed raw surfaces and was not a skin grafting candidate. The skin lesions of the patient were covered with cultured allogenic keratinocyte grafts and re-epithelialized quickly with no scarring. Allogenic keratinocyte grafting reduced pain and produced noticeable improvements in the unhealed wounds. We think that allogenic keratinocyte grafting can play an important role in the management of patients with EB simplex

Ocular surface epithelia contain ABCG2-dependent side population cells exhibiting features associated with stem cells.

When cell populations are incubated with the DNA-binding dye Hoechst 33342 and subjected to flow cytometry analysis for Hoechst 33342 emissions, active efflux of the dye by the ABCG2/BCRP1 transporter causes certain cells to appear as a segregated cohort, known as a side population (SP). Stem cells from several tissues have been shown to possess the SP phenotype. As the lack of specific surface markers has hindered the isolation and subsequent biochemical characterization of epithelial stem cells this study sought to determine the existence of SP cells and expression of ABCG2 in the epithelia of the ocular surface and evaluate whether such SP cells had features associated with epithelial stem cells. Human and rabbit limbal-corneal and conjunctival epithelial cells were incubated with Hoechst 33342, and analyzed and sorted by flow cytometry. Sorted cells were subjected to several tests to determine whether the isolated SP cells displayed features consistent with the stem cell phenotype. Side populations amounting to \u3c1% of total cells, which were sensitive to the ABCG2-inhibitor fumitremorgin C, were found in the conjunctival and limbal epithelia, but were absent from the stem cell-free corneal epithelium. Immunohistochemistry was used to establish the spatial expression pattern of ABCG2. The antigen was detected in clusters of conjunctival and limbal epithelia basal cells but was not present in the corneal epithelium. SP cells were characterized by extremely low light side scattering and contained a high percentage of cells that: showed slow cycling prior to tissue collection; exhibited an initial delay in proliferation after culturing; and displayed clonogenic capacity and resistance to phorbol-induced differentiation; all features that are consistent with a stem cell phenotype