Person:
Sánchez Ramos, Celia

First Name

Celia

Last Name

Sánchez Ramos

URI

https://hdl.handle.net/20.500.14352/79912

Affiliation

Universidad Complutense de Madrid

Faculty / Institute

Óptica y Optometría

Department

Optometría y Visión

Area

Optica

Identifiers

Full item page

Search Results

Now showing 1 - 10 of 26

Acid-sensing ion channels (ASICs) 2 and 4.2 are expressed in the retina of the adult zebrafish
(Cell and Tissue Research, 2015) Viña Fernández, Eliseo; Parisi, Valentina; Sánchez Ramos, Celia; Cabo, Roberto; Guerrera, María Cristina; Quirós, Luis Manuel; Germaná, Antonio M.; Vega, José Antonio; García Suárez, Olivia
Acid-sensing ion channels (ASICs) are H+-gated, voltage-insensitive cation channels involved in synaptic transmission, mechanosensation and nociception. Different ASICs have been detected in the retina of mammals but it is not known whether they are expressed in adult zebrafish, a commonly used animal model to study the retina in both normal and pathological conditions. We study the expression and distribution of ASIC2 and ASIC4 in the retina of adult zebrafish and its regulation by light using PCR, in situ hybridization, western blot and immunohistochemistry. We detected mRNA encoding zASIC2 and zASIC4.2 but not zASIC4.1. ASIC2, at the mRNA or protein level, was detected in the outer nuclear layer, the outer plexiform layer, the inner plexiform layer, the retinal ganglion cell layer and the optic nerve. ASIC4 was expressed in the photoreceptors layer and to a lesser extent in the retinal ganglion cell layer. Furthermore, the expression of both ASIC2 and ASIC4.2 was down-regulated by light and darkness. These results are the first demonstration that ASIC2 and ASIC4 are expressed in the adult zebrafish retina and suggest that zebrafish could be used as a model organism for studying retinal pathologies involving ASICs.
Elemento bloqueante de longitudes de onda corta en fuentes de iluminación de tipo LED
(2015) Sánchez Ramos, Celia; Universidad Complutense de Madrid
Método, producto y elemento bloqueante de longitudes de onda corta en fuentes de iluminación de tipo LED que consiste en un sustrato con un pigmento distribuido de manera uniforme en su superficie y, porque dicho pigmento tiene una densidad óptica tal que permite la absorción selectiva de longitudes de onda corta comprendidas entre 380 nm y 500 nm en un rango comprendido entre el 1 y el 99%.
Método y aparato para el reconocimiento biométrico corneal
(2019) Sánchez Ramos, Celia; Bonnin Arias, Cristina Natalia; Pascau González-Garzón, Javier; Moreta Martínez, Rafael; Universidad Complutense de Madrid, Universidad Carlos III de Madrid
Método de reconocimiento biométrico corneal que comprende: (i) capturar al menos una imagen de las superficies corneales; y (ii) cuantificar las irregularidades topográficas de dichas superficies corneales para obtener parámetros característicos y diferenciales de la topografía corneal para al menos un sujeto; y donde cada captura se configura como un registro con al menos un parámetro ocular; y que comprende una etapa de comparar: al menos un primer registro con al menos un parámetro ocular; y al menos un segundo registro del mismo parámetro ocular; y donde además comprende una etapa de clasificación de los datos resultantes de la comparación mediante un algoritmo de clasificación con auto-aprendizaje.
Technical Report: Potential risks to human health of Light Emitting Diodes (LEDs) (European Commission)
(2018) Ana Proykova; Theodoros Samaras; Rodica-Mariana Ion; Ellen M Bruzell; Jean-François Doré; Massimo Nicolo; John O'Hagan; Sánchez Ramos, Celia; Linda van Kerkhof
Following a request from the European Commission, the Scientific Committee on Health, Environmental and Emerging Risks (SCHEER) reviewed recent evidence to assess potential risks to human health posed by Light Emitting Diodes (LEDs) emissions. The review of the published research conducted by the SCHEER has led to valuable conclusions and identified certain gaps in knowledge on potential risks to human health from LEDs. The Committee concluded that there is no evidence of direct adverse health effects from LEDs emission in normal use (lamps and displays) by the general healthy population. There is some evidence that exposure to light in the late evening, including that from LED lighting and/or screens, may have an impact on the circadian rhythm. At the moment, it is not yet clear if this disturbance of the circadian system leads to adverse health effects. Vulnerable and susceptible populations (young children, adolescents and elderly people) have been considered separately. Children have a higher sensitivity to blue light and although emissions may not be harmful, blue LEDs (between 400 nm and 500 nm) including those in toys may be very dazzling and may induce photochemical retinopathy, which is a concern especially for children below three years of age. Older people may experience discomfort from exposure to light that is rich in blue light. Although there are cellular and animal studies showing adverse effects raising concerns, particularly in susceptible populations, their conclusions derive from results obtained either using exposure conditions that are difficult to relate to human exposures or using exposure levels greater than those likely to be achieved with LED lighting systems in practice. Some LEDs present potential health concerns due to temporal light modulation (flicker) at frequencies of 100 Hz and above. Reliable information on the dose-response relationship for adverse health effects for the healthy general public is not available in the scientific literature for all wavelengths emitted by LED devices. Since the use of LED technology is still evolving, the Committee considers that it is important to closely monitor the risk of adverse health effects from long-term LED use by the general population.
Dioptrio bloqueante de radiaciones de longitudes de onda corta y media del espectro visible que afecta a la fisiología humana
(2017) Sánchez Ramos, Celia; García Manchado, Nilo; Universidad Complutense de Madrid / Tecnología Sostenible y Responsable SL
Dioptrio bloqueante de radiaciones de longitudes onda corta y media del espectro visible que afectan la fisiología humana que comprende la absorción selectiva de longitudes de onda corta comprendidas entre 380 nm y 500 nm entre un umbral máximo y un umbral mínimo de absorción; y la absorción selectiva de longitudes de onda media comprendida entre 500 nm y 590 nm entre un umbral máximo y un umbral mínimo de absorción; y donde la absorción selectiva de longitudes de onda corta y media comprendidas entre los 380-590 nm no bloquea totalmente el paso de luz visible en dicho rango. Otras realizaciones incluyen una pantalla LED, un producto de programa informático y un dispositivo electrónicoy lentes, oftálmicas, intraoculares u solares.
Dispositivo y Método simulador de entornos para la evaluación de la función visual
(2018) Sánchez Ramos, Celia; Bonnin Arias, Cristina Natalia; Universidad Complutense de Madrid
Dispositivo y método simulador de entornos de evaluación de la función visual que comprende un soporte que aloja un luxómetro medidor de la iluminación ambiente que comprende una pluralidad de dioptrios de densidad óptica neutra (DO); y donde la relación entre la densidad óptica y la transmitancia (T) del dioptrio viene dada por DO=log(1/T); y donde los dioptrios de densidad óptica neutra (DO) están dispuestos en el soporte en correspondencia con el sistema visual de un individuo y configurados para alcanzar distintos niveles de iluminación directamente en el sistema visual del individuo sin realizar una variación real de la iluminación ambiente.
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, Francisco
Light 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.
Short term visual outcomes of a new trifocal intraocular lens
(BMC Ophthalmology, 2017) García Pérez, Jorge L.; Gros Otero, Juan; Sánchez Ramos, Celia; Blázquez Sánchez, Vanesa; Contreras Martín, Inés
Background: Today, patients often expect to achieve spectacle independance after cataract surgery. New trifocal intraocular lenses have been developed to try and fullfill this demand. The purpose of this study is to report the short-term visual outcomes of a new trifocal intraocular lens (AcrySof PanOptix™). Methods: Consecutive adult patients undergoing cataract surgery with bilateral implantation of the study intraocular lens in a private practice clinic were considered for inclusion. Exclusion criteria were the presence of other ocular pathologies or preoperative astigmatism >1.5 diopters (D). Patients with intraoperative complications were excluded from analysis. One month after surgery patients underwent: monocular defocus curve; monocular and binocular uncorrected visual acuity in photopic and mesopic conditions, for far (4 m), intermediate (60 cm) and near (33 cm) distances and binocular contrast sensitivity. Patients completed a visual satisfaction questionnaire between 9 and 12 months after surgery. Results: One hundred and sixteen eyes of fifty-eight patients receiving bilateral implantation of the study intraocular lens were analysed. Mean binocular uncorrected visual acuity in photopic conditions was 0.03 LogMAR for far, 0.12 for intermediate and 0.02 for near distances. All patients achieved a binocular uncorrected visual acuity better than 0.3 LogMAR (20/40 Snellen equivalent) for distance and near vision and 94.8% of patients for intermediate vision. Mesopic binocular uncorrected visual acuity values were similar to photopic values. The monocular defocus curves showed that the best visual acuity was reached at a vergence of 0.00D. Visual acuity dropped slightly at −1.00D and peaked again at −2.00D. Visual acuities better than 0.2 LogMAR were maintained between −2.50D and +0.50D. Contrast sensitivity was high and similar in photopic and mesopic conditions. As regards patient-evaluated outcomes, only 2 patients (3.4%) were fairly dissatisfied with their sight after surgery. Three patients (5.1%) reported the need for spectacle correction for certain activities. All other patients (94.8%) reported never using spectacle correction. Conclusions: The PanOptix trifocal IOL provides good short-term visual outcomes, with good intermediate performance and excellent patient-reported satisfaction. The similar values achieved in mesopic and photopic conditions in binocular uncorrected visual acuity and contrast sensitivity suggest low pupillary dependence for light distribution. Trial registration number: ISRCTN60143265 , retrospectively registered on the 24th of April 2017.
DEVICE AND METHOD FOR THE DETECTION AND QUANTIFICATION OF VARIATION IN EYE DAMAGE CAUSED BY BLUE AND VIOLET LIGHT IN THE VISIBLE SPECTRUM
(2019) García Manchado Nilo; Sánchez Ramos, Celia; "Universidad Complutense de Madrid", "CRAMBO S.A."
Método, dispositivo (100) y sistema (200) para la detección y cuantificación de la variación del daño ocular provocado por la luz azul y violeta del espectro visible que comprende las etapas de detectar la radiación incidente sobre el sistema visual de un individuo; calcular la radiación incidente dentro del rango comprendido entre 380 y 500 nm; establecer al menos un umbral de radiaciones incidentes dentro de dicho rango; detectar si se ha superado al menos un umbral establecido para dicho rango; avisar de la superación de al menos un umbral; medir el tiempo de exposición a la radiación incidente; e inferir en las distintas estructuras oculares de un individuo el efecto de las radiaciones incidentes y avisar de dicho efecto.
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, Celia
Human 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.