Person: Sánchez Ramos, Celia
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First Name
Celia
Last Name
Sánchez Ramos
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Optometría y Visión
Area
Optica
Identifiers
4 results
Search Results
Now showing 1 - 4 of 4
Item Removal of the blue component of light significantly decreases retinal damage after high intensity exposure(PLoS ONE, 2018) Vicente-Tejedor, Javier; Marchena, Miguel; Ramírez, Laura; García Ayuso, Diego; Gómez Vicente, Violeta; Sánchez Ramos, Celia; Villa Polo, Pedro de la; Germain, FranciscoLight causes damage to the retina (phototoxicity) and decreases photoreceptor responses to light. The most harmful component of visible light is the blue wavelength (400–500 nm). Different filters have been tested, but so far all of them allow passing a lot of this wavelength (70%). The aim of this work has been to prove that a filter that removes 94% of the blue component may protect the function and morphology of the retina significantly. Three experimental groups were designed. The first group was unexposed to light, the second one was exposed and the third one was exposed and protected by a blue-blocking filter. Light damage was induced in young albino mice (p30) by exposing them to white light of high intensity (5,000 lux) continuously for 7 days. Short wavelength light filters were used for light protection. The blue component was removed (94%) from the light source by our filter. Electroretinographical recordings were performed before and after light damage. Changes in retinal structure were studied using immunohistochemistry, and TUNEL labeling. Also, cells in the outer nuclear layer were counted and compared among the three different groups. Functional visual responses were significantly more conserved in protected animals (with the blue-blocking filter) than in unprotected animals. Also, retinal structure was better kept and photoreceptor survival was greater in protected animals, these differences were significant in central areas of the retina. Still, functional and morphological responses were significantly lower in protected than in unexposed groups. In conclusion, this blue-blocking filter decreases significantly photoreceptor damage after exposure to high intensity light. Actually, our eyes are exposed for a very long time to high levels of blue light (screens, artificial light LED, neons…). The potential damage caused by blue light can be palliated.Item Retinal protection from LED-backlit screen lights by short wavelength absorption filters(Cells, 2021) Sánchez Ramos, Celia; Bonnin Arias, Cristina Natalia; Blázquez Sánchez, Vanesa; Aguirre Vilacoro, Victoria; Cobo Díaz, Teresa; García Suárez, Olivia; Pérez Carrasco, María Jesús; Álvarez Peregrina, Cristina; Vega Álvarez, José AntonioBackground: Ocular exposure to intense light or long-time exposure to low-intensity short-wavelength lights may cause eye injury. Excessive levels of blue light induce photochemical damage to the retinal pigment and degeneration of photoreceptors of the outer segments. Currently, people spend a lot of time watching LED screens that emit high proportions of blue light. This study aims to assess the effects of light emitted by LED tablet screens on pigmented rat retinas with and without optical filters. Methods: Commercially available tablets were used for exposure experiments on three groups of rats. One was exposed to tablet screens, the other was exposed to the tablet screens with a selective filter and the other was a control group. Structure, gene expression (including life/death, extracellular matrix degradation, growth factors, and oxidative stress related genes), and immunohistochemistry in the retina were compared among groups. Results: There was a reduction of the thickness of the external nuclear layer and changes in the genes involved in cell survival and death, extracellular matrix turnover, growth factors, inflammation, and oxidative stress, leading decrease in cell density and retinal damage in the first group. Modulation of gene changes was observed when the LED light of screens was modified with an optical filter. Conclusions: The use of short-wavelength selective filters on the screens contribute to reduce LED light-induced damage in the rat retina.Item Efecto de la luz: Alternativas de protección ante la luz azul(Franja visual, 2019) Bonnin Arias, Cristina Natalia; Gutiérrez Jorrín, Sara.; Rodríguez Alonso, Xabier; Sánchez Ramos, CeliaLa luz azul comprende la radiación luminosa entre 380 y 500 nm y constituye la banda más energética del espectro visible. La luz azul, además de ser emitida por el sol con altas intensidades, es la base de la luz LED emitida por las pantallas de todo tipo de dispositivos electrónicos utilizados actualmente (smartphones, tablets, ordenadores…). Esta iluminación LED fomenta el cansancio visual, dificultando la visión, produciendo resequedad en los ojos y dolores de cabeza, llegando, incluso, a alterar los ciclos circadianos. Además, numerosas investigaciones han demostrado que, dentro del espectro visible, la luz azul es la más dañina para la retina,pudiendo desembocar, finalmente, en una degeneración macular precoz.Item Effects of Light‐emitting Diode Radiations on Human Retinal Pigment Epithelial Cells in vitro(Photochemistry and Photobiology, 2012) Chamorro, Eva; Muñoz de Luna, Javier; Bonnin Arias, Cristina Natalia; Pérez Carrasco, María Jesús; Vázquez Molini, Daniel; Sánchez Ramos, CeliaHuman visual system is exposed to high levels of natural and artificial lights of different spectra and intensities along lifetime. Light-emitting diodes (LEDs) are the basic lighting components in screens of PCs, phones and TV sets; hence it is so important to know the implications of LED radiations on the human visual system. The aim of this study was to investigate the effect of LEDs radiations on human retinal pigment epithelial cells (HRPEpiC). They were exposed to three light-darkness (12 h/12 h) cycles, using blue-468 nm, green-525 nm, red-616 nm and white light. Cellular viability of HRPEpiC was evaluated by labeling all nuclei with DAPI; Production of reactive oxygen species (ROS) was determined by H2DCFDA staining; mitochondrial membrane potential was quantified by TMRM staining; DNA damage was determined by H2AX histone activation, and apoptosis was evaluated by caspases-3,-7 activation. It is shown that LED radiations decrease 75-99% cellular viability, and increase 66-89% cellular apoptosis. They also increase ROS production and DNA damage. Fluorescence intensity of apoptosis was 3.7% in nonirradiated cells and 88.8%, 86.1%, 83.9% and 65.5% in cells exposed to white, blue, green or red light, respectively. This study indicates three light-darkness (12 h/12 h) cycles of exposure to LED lighting affect in vitro HRPEpiC.