Person: Bonnin Arias, Cristina Natalia
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First Name
Cristina Natalia
Last Name
Bonnin Arias
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Optometría y Visión
Area
Optica
Identifiers
6 results
Search Results
Now showing 1 - 6 of 6
Item Light regulates the expression of the BDNF/TrkB system in the adult Zebrafish retina(Microscopy Research and Technique, 2012) Guerrera, María Cristina; García Calavia, Marta; Chamorro Gutiérrez, Eva; Montalbano, Giuseppe; López Velasco, Salvador; López Muñiz, Alfonso Joaquín; Germanà, Antonino; Vega Álvarez, José Antonio; Sánchez Ramos, Celia; Bonnin Arias, Cristina NataliaThe retina of the adult zebrafish express brain‐derived neurotrophic factor (BDNF) and its signaling receptor TrkB. This functional system is involved in the biology of the vertebrate retina and its expression is regulated by light. This study was designed to investigate the effects of cyclic (12 h light/12 h darkness) or continuous (24 h) exposure during 10 days to white light, white‐blue light, and blue light, as well as of darkness, on the expression of BDNF and TrkB in the retina. BDNF and TrkB were assessed in the retina of adult zebrafish using quantitative real‐time polymerase chain reaction and immunohistochemistry. Exposure to white, white‐blue, and blue light causes a decrease of BDNF mRNA and of BDNF immunostaining, independently of the pattern of light exposition. Conversely, in the same experimental conditions, the expression of TrkB mRNA was upregulated and TrkB immunostaining increased. Exposition to darkness diminished BDNF and TrkB mRNAs, and abolished the immunostaining for BDNF but not modified that for TrkB. These results demonstrate the regulation of BDNF and TrkB by light in the retina of adult zebrafish and might contribute to explain some aspects of the complex pathophysiology of light‐induced retinopathies.Item Development of a Method to Potentially Substitute Direct Evaluation of Mesopic Visual Acuity in Drivers(International Journal of Environmental Research and Public Health, 2021) García Rojo, Marta María; Bonnin Arias, Cristina Natalia; Chamorro Gutiérrez, Eva; Álvarez Peregrina, Cristina; Sánchez Ramos, Celia(1) Background: In mesopic lighting conditions, or under adverse environmental circumstances, visual information is reduced, which increases the risk of traffic accidents. This effect could be reduced with a precise evaluation of the visual function under mesopic conditions, but it is difficult to replicate in clinics. This study aims to develop an easy-to-adopt method to evaluate mesopic visual acuity (VA) in drivers. (2) Methods: Prospective and observational study in drivers. logMAR mesopic VA was compared with photopic VA measured under different combinations of contrast charts and filters to find the combination that responds best to mesopic conditions. (3) Results: Fifty-six drivers were examined. The best correlation was found with an 80% density filter and a Weber contrast chart of 20%. The logMAR VA for this combination was 0.01 ± 0.11, which was close to the mesopic VA values (0.01 ± 0.12). The difference between both logMAR VA was 0.00 ± 0.06 (R = 0.86; p ≤ 0.001; ICC = 0.86). (4) Conclusions: The use of 20% contrast optotypes and the interposition of an 80% filter under photopic conditions provide VA values similar to those measured under mesopic lighting conditions, making this simple system a good predictor of mesopic VA values.Item Espesor macular medido con tomografía de coherencia óptica en ojos pseudoafáquicos con implante amarillo vs. transparente(Archivos de la Sociedad Española de Oftalmología, 2014) Chamorro Gutiérrez, Eva; Bonnin Arias, Cristina Natalia; Perez Carrasco, Maria Jesus; Álvarez-Rementería Fernández, Laureano; Villa Collar, César; Armada Maresca, María Isabel; Sánchez Ramos, Celia; Pérez Carrasco, María JesúsObjetivo: Evaluar mediante tomografía de coherencia óptica (OCT) las variaciones de espesor macular producidas a lo largo del tiempo en ojos pseudoafáquicos implantados con una lente intraocular (LIO) transparente en comparación con sus respectivos ojos contralarerales implantados con LIO amarilla. Métodos: El espesor macular de 36 ojos de 18 sujetos fue evaluado mediante OCT. Los sujetos presentaban edades superiores a 65 años y habían sido intervenidos de cataratas en ambos ojos en 2 cirugías independientes. La principal característica de los individuos es que llevaban implantada una LIO con diferente absorción en cada ojo: transparente (absorbente de la radiación ultravioleta) y amarilla (con filtro adicional absorbente de las radiaciones violeta-azul del espectro visible). El espesor macular se evaluó en 2 sesiones separadas en el tiempo por un intervalo de tiempo de 5 años, mediante el sistema Stratus-OCT (protocolo fast macular thickness). Se analizaron estadísticamente las diferencias en la evolución del espesor macular entre ojos con diferente tipo de LIO. Resultados: Tras 5 años de seguimiento, se observó que los ojos implantados con LIO transparente manifestaban una reducción del espesor macular estadísticamente significativa, superior a la esperada por el aumento de la edad. Sin embargo, los ojos implantados con LIOs amarillas mantuvieron su espesor macular estable. La disminución del espesor macular promedio en ojos implantados con LIO transparente fue de 5 ± 8 μm (p = 0,02) y la reducción del espesor foveal fue de 10 ± 17 μm (p = 0,02). Conclusiones: Los cambios de espesor macular producidos en ojos implantados con una LIO amarilla difieren de los cambios manifestados en ojos con LIO transparente. Estas observaciones apuntan a un posible efecto protector de las LIOs amarillas contra los efectos dañinos de la luz en sujetos pseudoafáquicos. Sin embargo, estudios con un mayor tamaño muestral y mayor tiempo de seguimiento son necesarios para confirmar que la protección inducida por este tipo de LIO es clínicamente significativa.Item Utilidad de la pupilometría dinámica en el control de alcoholemia de los conductores(Adicciones, 2013) Lobato Rincón, Luis-Lucio; Cabanillas Campos, María del Carmen; Navarro Valls, Juan José; Bonnin Arias, Cristina Natalia; Chamorro Gutiérrez, Eva; Sánchez Ramos, CeliaLa pupilometría se ha convertido en una herramienta de gran interés en las Ciencias de la Visión. Hasta el momento, solo unos pocos estudios han explorado la relación entre el reflejo pupilar y el consumo de drogas. El objetivo de este estudio fue evaluar la aplicabilidad de la pupilometría dinámica mesópica como método objetivo para la detección de niveles de alcoholemia por encima del límite legal. Se utilizó un diseño de carácter cuasi-experimental, con 19 voluntarios participando en dos condiciones (pre y post ingesta de alcohol). En la sesión con alcohol, los participantes consumieron 27.5 ml de alcohol en intervalos de 60 minutos durante 4 horas. Se llevaron a cabo registros de pupilometría mediante el Power Refractor II, utilizándose cuatro tipos de estimulación lumínica: blanca (5600 K), azul (450 nm), verde (510 nm) y roja (600 nm). El diámetro basal aumentó significativamente a partir de concentraciones de alcohol en aire espirado iguales o mayores de 0.25 mg/l. Además, el valor de la amplitud de constricción para la luz roja también ofreció diferencias significativas entre las dos condiciones. Estos resultados resultan prometedores en la búsqueda de nuevos métodos de detección de niveles de alcoholemia no permitidos al volante. En este estudio se demuestra que el incremento del diámetro basal y la amplitud pupilar pueden ser utilizados como indicador del nivel de consumo de alcohol. Son necesarios más estudios para validar éste y otros métodos de diagnóstico complementarios a las actuales pruebas de alcoholemia y de consumo de sustancias psicotropas.Item Pupillary behavior in relation to wavelength and age(Frontiers in Human Neuroscience, 2014) Lobato Rincón, Luis-Lucio; Cabanillas Campos, María del Carmen; Bonnin Arias, Cristina Natalia; Chamorro Gutiérrez, Eva; Sánchez Ramos, Celia; Murciano Cespedosa, AntonioPupil light reflex can be used as a non-invasive ocular predictor of cephalic autonomic nervous system integrity. Spectral sensitivity of the pupil's response to light has, for some time, been an interesting issue. It has generally, however, only been investigated with the use of white light and studies with monochromatic wavelengths are scarce. This study investigates the effects of wavelength and age within three parameters of the pupil light reflex (amplitude of response, latency, and velocity of constriction) in a large sample of younger and older adults (N = 97), in mesopic conditions. Subjects were exposed to a single light stimulus at four different wavelengths: white (5600° K), blue (450 nm), green (510 nm), and red (600 nm). Data was analyzed appropriately, and, when applicable, using the General Linear Model (GLM), Randomized Complete Block Design (RCBD), Student's t-test and/or ANCOVA. Across all subjects, pupillary response to light had the greatest amplitude and shortest latency in white and green light conditions. In regards to age, older subjects (46-78 years) showed an increased latency in white light and decreased velocity of constriction in green light compared to younger subjects (18-45 years old). This study provides data patterns on parameters of wavelength-dependent pupil reflexes to light in adults and it contributes to the large body of pupillometric research. It is hoped that this study will add to the overall evaluation of cephalic autonomic nervous system integrity.Item Visual Discrimination Increase by Yellow Filters in Retinitis Pigmentosa(Optometry and Vision Science, 2016) Cedrún Sánchez, Juan Enrique; Chamorro Gutiérrez, Eva; Bonnin Arias, Cristina Natalia; Aguirre Vilacoro, Victoria; Castro, José J.; Sánchez Ramos, CeliaPURPOSE: The objective of this study was to evaluate, by halometry and under low illumination conditions, the effects of short-wavelength light absorbance filters on visual discrimination capacity in retinitis pigmentosa patients. METHODS: This was an observational, prospective, analytic, and transversal study on 109 eyes of 57 retinitis pigmentosa patients with visual acuity better than 1.25 logMAR. Visual disturbance index (VDI) was determined using the software Halo 1.0, with and without the interposition of filters which absorb (totally or partially) short-wavelength light between 380 and 500 nm. RESULTS: A statistically significant reduction in the VDI values determined using filters which absorb short-wavelength light was observed (p < 0.0001). The established VDIs in patients with VA logMAR <0.4 were 0.30 ± 0.05 (95% CI, 0.26–0.36) for the lens alone, 0.20 ± 0.04 (95% CI, 0.16–0.24) with the filter that completely absorbs wavelengths shorter than 450 nm, and 0.24 ± 0.04 (95% CI, 0.20–0.28) with the filter that partially absorbs wavelengths shorter than 450 nm, which implies a 20 to 33% visual discrimination capacity increase. In addition, a decrease of VDI in at least one eye was observed in more than 90% of patients when using a filter. CONCLUSIONS: Short-wavelength light absorbance filters increase visual discrimination capacity under low illumination conditions in retinitis pigmentosa patients. Use of such filters constitutes a suitable method to improve visual quality related to intraocular light visual disturbances under low illumination conditions in this group of patients. © 2016 American Academy of Optometry