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
3 results
Search Results
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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 Evaluation and inter-observer analysis of retinography existing clinical classification system to categorize moderate retinopathies.(2009) Sánchez Ramos, Celia; Wasfi, M.; Bonnin Arias, Cristina Natalia; Vinas Pena, M.; Forlán, A.; Molina Gómez, C.; Chamorro Gutiérrez, E.PURPOSE: To evaluate existing validated systems to classify retinopathies, to determine the interobserver agreement level. METHODS: 55 retinographies (both gender >60 years old) were categorized following 3 stablished criteria: the International Classification and Grading System for ARM and AMD (BIRD), the Wisconsin Age-related Maculophathy Grading System (WISCONSIN) and the Clinical Age-related Maculophathy Staging System (CARMS). The categorizing was made by 2 experts in a blind, independent way. The goal of the doubled-classification-method, with changing order no randomised, was to reject the influence of the Velo effect. Inter-observer´s repeatability was checked as an agreement parameter between both Experts. RESULTS: CARMS system was chosen, since allows a global pathology classification. CARMS concordance obtained was 81.89% (expected= 57.39% kappa index = 0.57). Drusen concordance obtained was 87.27% (Expected= 60.31% kappa index = 0.68). Pigmentation concordance obtained was 76.36% (expected = 54.46% kappa index= 0.48). The reliability measured by Kappa index followed the rule: 0.80-1.00 (Excellent). 0.60-0.80 (Good) and 0.40-0.60 (Moderate). 0.20-0.40 (Low) < 0.20 (Bad) CONCLUSION: Existin Retinopathies classification systems can be improved, to solve the huge subjective level that they present. Kappa index obtained, shown medium concordance for the inter-observer analysis, except in Drusen case, dichotomy`s variable, which presented a good reliability. The worse behaviour of the Pigmentation´s variable respect to Drusen variable has to be noted. This has an important influence in the global CARMS reliability, so it makes this influence to fall down.Item Effects of prolonged exposure to different types of light on the rabbit retina: gene expression of TIMPs and VEGFR2.(2010) Sánchez Ramos, Celia; Vega, J.A.; Bonnin Arias, Cristina Natalia; Chamorro Gutiérrez, E.; González Montero, María Guadalupe; Niño Rueda, AranzazuPUPORSE: Some forms of age-related macular disease are characterized by the appearance deposits arising from abnormal extracellular matrix processing and vascular proliferation. The activity of MMP3 and MMP9 is potentiated by prolonged exposure to light, This study examines the effects of light of varying spectral composition on the type 2 vascular endothelium growth factor receptor ( VEGFR2) and on tissue inhibitors of MMPs (TIMPs). METHODS: We examined the retinas of rabbits implanted with a transparent IOL in one eye and a yellow IOL in the other and then exposed to light of different spectral composition over an average time of 2 years. Total RNA was extracted from retinas isolated from the different groups of animals. Levels of mRNA for the genes TIMP1, TIMP2 and VEGFR2 were determined by quantifying PCR products using a Phosphorlmager (Fuji). RESULTS: TIMP1/2 and VEGFR2 gene expression levels detected in the retinas exposed to white light were normal. In contrast, exposure to white light lacking the blue band was related to a marked drop in TIMP1 expression, a slight drop in VEGFR2 expression and unaltered TIMP2 expression. When retinas were exposed to blue light the increased expression of all three genes was observed compared to expression patterns produced in response to while light (TIMP1 3-fold, TIMP2 6- fold, VEGFR2 4-fold). This gene up-regulation was reduced by the use of a yellow IOL when the animals were exposed to white light containing a high percentage of blue light. CONCLUSIONS: The up-regulation of the genes coding for TIMPs and VEGFR2 produced after exposure to blue light suggests that the blue region of the light spectrum plays a direct role in the etiology of macular degeneration an that these changes induced by light coul be prevent using an IOL that blocks blue light.