Person:
Pérez Carrasco, María Jesús

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First Name
María Jesús
Last Name
Pérez Carrasco
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Optometría y Visión
Area
Optica
Identifiers
UCM identifierORCIDScopus Author IDWeb of Science ResearcherIDDialnet ID

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Now showing 1 - 5 of 5
  • 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, 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.
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    Effect of a yellow filter on mesopic contrast perception and differential light sensitivity in the visual field.
    (Ophthalmic Research, 2003) Pérez Carrasco, María Jesús; Puell Marín, María Cinta; Sánchez Ramos, Celia; Langa Moraga, Antonio
    Purpose: Previous studies on the effects of yellow filters in the visual performance have been carried out, presenting discrepancies among the different investigations. Our study reports the influence of the yellow filter without residual reflections on contrast perception and differential light sensitivity (DLS) under mesopic conditions. Methods: Contrast sensitivity, low contrast visual acuity and luminance thresholds in the central visual field (30 degrees ) were measured in a group of 38 adult subjects with and without a coated yellow lens (482-nm cut-off) under mesopic conditions. Results: The contrast sensitivity mean was significantly better with the filter at low- and middle-range spatial frequencies (1.5 cycles/degree p = 0.002 and 6 cycles/degree p = 0.02). At 5% contrast, the mesopic low contrast visual acuity improved significantly (p = 0.004) when interposing the yellow filter. The increase in DLS was statistically significant [e.g. all visual fields p = 0.0003 and macular visual field (9.5 degrees ) p = 0.00001] through the yellow filter on the different established areas of the visual field (30 degrees ). Conclusions: The yellow filter without residual reflections had a positive influence on the brightness and contrast perception of healthy subjects, for which its use would be beneficial under mesopic conditions.
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    Nuevo instrumento para medir la sensibilidad al contraste sin y con deslumbramiento
    (Archivos de la Sociedad Española de Oftalmología, 2003) Sánchez Ramos, Celia; Puell Marín, María Cinta; Pérez Carrasco, María Jesús; Langa Moraga, Antonio; Benítez Del Castillo Sánchez, José Manuel
    OBJETIVO/MÉTODO: valorar la sensibilidad al contraste fotópica, sin y con deslumbramiento con un nuevo instrumento. Se estudiaron 78 ojos derechos de 49 adultos jóvenes y de 29 adultos entre 35 y 55 años. La sensibilidad al contraste se midió con el Contrast Glarester CGT-1000 mediante una estrategia automatizada de reconocimiento para seis frecuencias espaciales. RESULTADOS/CONCLUSIONES: Los valores de sensibilidad al contraste fueron semejantes a los obtenidos con otros test clínicos. El aumento de la edad disminuyó significativamente la sensibilidad al contraste sin y con deslumbramiento. Sin embargo, el deslumbramiento no modificó la sensibilidad al contraste fotópica.
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    New Optical Filter Plate for Use as Eye Protection by Welders
    (Welding journal, 2013) Langa Moraga, Antonio; Bonnin Arias, Cristina Natalia; Chamorro, Eva; Pérez Carrasco, María Jesús; Sánchez Ramos, Celia
    People whose work tasks involve the use of welding torches are at special risk of suffering eye injuries due to the emission of visible, short-wavelength radiation. Current legislation requires that a company provide its employees with protection against the harmful radiation produced by welding equipment. Often, however, a worker will be reluctant to use protective goggles since these markedly cut visibility and can consequently lead to errors or even burns. This practice of avoiding the use of protection makes them susceptible to suffer irreversible severe retinal damage leading to partial or complete loss of vision. In this paper, we propose the use of a new photoprotective filter in the form of safety goggles that seeks to improve the compromised vision produced by conventional filters. We compare a series of visual function variables in 36 adults, aged 30 to 58 years, using the new optical filter and a conventional filter used for welding protection. Our findings suggest that the filter proposed provides optimal protection against the harmful effects of short-wavelength radiation while minimizing the reduced vision effects of conventional filters used for this purpose.
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    Contrast sensitivity and disability glare in patients with dry eye
    (Acta Ophthalmologica Scandinavica, 2006) Puell Marín, María Cinta; Benítez Del Castillo Sánchez, José Manuel; Martínez De La Casa Fernández-Borrella, José María; Sánchez Ramos, Celia; Aladro Vico, Eva; Pérez Carrasco, María Jesús; Pedraza Aranda, Constanza; Hierro Zarzuelo, Almudena, del
    Purpose: To evaluate contrast sensitivity and disability glare in patients with dry eye using the Contrast Glaretester 1000. Methods: Contrast sensitivity and disability glare were determined in 33 eyes of 33 patients with dry eye and 30 eyes of 30 healthy control subjects for six target sizes with a visual angle of 6.3-0.7 degrees using the Contrast Glaretester 1000, whose working mechanism is similar to that of the conventional perimetry instrument. Results: Contrast sensitivity was significantly worse in dry eye group when viewing all target sizes (reduction of 0.10-0.25 log contrast units, p < 0.01) except at 6.3 degrees. In the presence of glare, differences in log contrast sensitivity between the groups (0.10-0.25 units) were significant (p < 0.01) for all target sizes, with the dry eye group showing worse results. The reduction in contrast sensitivity induced by glare (disability glare) was significantly worse in the dry eye group versus the control group but only for the 2.5-degree size target, where 0.14 log contrast units were lost. Conclusions: Contrast sensitivity with and without glare was significantly reduced in patients with dry eye compared with control subjects, but the number of log contrast units lost with glare (disability glare) was similar in the two groups, except for the 2.5-degree size target.