Person:
Ramírez Toraño, Federico

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First Name
Federico
Last Name
Ramírez Toraño
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Psicología
Department
Psicología Experimental, Procesos Cognitivos y Logopedia
Area
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Now showing 1 - 3 of 3
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    Foveal Avascular Zone and Choroidal Thickness Are Decreased in Subjects with Hard Drusen and without High Genetic Risk of Developing Alzheimer’s Disease
    (Biomedicines, 2021) López Cuenca, Inés; Hoz Montañana, María Rosa de; Alcántara Rey, Celia; García Martín, Elena Salobrar; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Barabash, Ana; Ramírez Toraño, Federico; Frutos Lucas, Jaisalmer de; Salazar Corral, Juan José; Ramírez Sebastián, Ana Isabel; Ramirez Sebastian, Jose Manuel
    A family history (FH+) of Alzheimer’s disease (AD) and ε4 allele of the ApoE gene are the main genetic risk factors for developing AD, whereas ε4 allele plays a protective role in age-related macular degeneration. Ocular vascular changes have been reported in both pathologies. We analyzed the choroidal thickness using optical coherence tomography (OCT) and the foveal avascular zone (FAZ) using OCT-angiography and compared the results with ApoE gene expression, AD FH+, and the presence or absence of hard drusen (HD) in 184 cognitively healthy subjects. Choroidal thickness was statistically significantly different in the (FH−, ε4−, HD+) group compared with (i) both the (FH−, ε4−, HD−) and the (FH+, ε4+, HD+) groups in the superior and inferior points at 1500 µm, and (ii) the (FH+, ε4−, HD+) group in the superior point at 1500 µm. There were statistically significant differences in the superficial FAZ between the (FH+, ε4−, HD+) group and (i) the (FH+, ε4−, HD−) group and (ii) the (FH+, ε4+, HD−) group. In conclusion, ocular vascular changes are not yet evident in participants with a genetic risk of developing AD.
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    Characterization of Retinal Drusen in Subjects at High Genetic Risk of Developing Sporadic Alzheimer’s Disease: An Exploratory Analysis
    (Journal of Personalized Medicine, 2022) López Cuenca, Inés; García Martín, Elena Salobrar; Gil Salgado, Inés; Sánchez Puebla, Lídia; Elvira Hurtado, Lorena; Fernández Albarral, José Antonio; Ramírez Toraño, Federico; Barabash, Ana; Frutos Lucas, Jaisalmer de; Salazar Corral, Juan José; Ramirez Sebastian, Jose Manuel; Ramírez Sebastián, Ana Isabel; Hoz Montañana, María Rosa de
    Having a family history (FH+) of Alzheimer’s disease (AD) and being a carrier of at least one ɛ4 allele of the ApoE gene are two of the main risk factors for the development of AD. AD and age-related macular degeneration (AMD) share one of the main risk factors, such as age, and characteristics including the presence of deposits (Aβ plaques in AD and drusen in AMD); however, the role of apolipoprotein E isoforms in both pathologies is controversial. We analyzed and characterized retinal drusen by optical coherence tomography (OCT) in subjects, classifying them by their AD FH (FH- or FH+) and their allelic characterization of ApoE ɛ4 (ApoE ɛ4- or ApoE ɛ4+) and considering cardiovascular risk factors (hypercholesterolemia, hypertension, and diabetes mellitus). In addition, we analyzed the choroidal thickness by OCT and the area of the foveal avascular zone with OCTA. We did not find a relationship between a family history of AD or any of the ApoE isoforms and the presence or absence of drusen. Subjects with drusen show choroidal thinning compared to patients without drusen, and thinning could trigger changes in choroidal perfusion that may give rise to the deposits that generate drusen
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    Early visual alterations in individuals at-risk of Alzheimer’s disease: a multidisciplinary approach
    (Alzheimer's Research & Therapy, 2023) López Cuenca, Inés; Nebreda Pérez, Alberto; García Colomo, Alejandra; García Martín, Elena Salobrar; Frutos Lucas, Jaisalmer de; Bruña Fernández, Ricardo; Ramírez Sebastián, Ana Isabel; Ramírez Toraño, Federico; Salazar Corral, Juan José; Barabash, Ana; Gil, Pedro; Maestú Unturbe, Fernando; Ramirez Sebastian, Jose Manuel; Hoz Montañana, Rosa de
    Background: The earliest pathological features of Alzheimer’s disease (AD) appear decades before the clinical symptoms. The pathology affects the brain and the eye, leading to retinal structural changes and functional visual alterations. Healthy individuals at high risk of developing AD present alterations in these ophthalmological measures, as well as in resting-state electrophysiological activity. However, it is unknown whether the ophthalmological alterations are related to the visual-related electrophysiological activity. Elucidating this relationship is paramount to understand the mechanisms underlying the early deterioration of the system and an important step in assessing the suitability of these measures as early biomarkers of disease. Methods: In total, 144 healthy subjects: 105 with family history of AD and 39 without, underwent ophthalmologic analysis, magnetoencephalography recording, and genotyping. A subdivision was made to compare groups with less demographic and more risk differences: 28 high-risk subjects (relatives/APOEɛ4 +) and 16 low-risk (non-relatives/APOEɛ4 −). Differences in visual acuity, contrast sensitivity, and macular thickness were evaluated. Correlations between each variable and visual-related electrophysiological measures (M100 latency and time–frequency power) were calculated for each group. Results: High-risk groups showed increased visual acuity. Visual acuity was also related to a lower M100 latency and a greater power time–frequency cluster in the high-risk group. Low-risk groups did not show this relationship. High-risk groups presented trends towards a greater contrast sensitivity that did not remain significant after correction for multiple comparisons. The highest-risk group showed trends towards the thinning of the inner plexiform and inner nuclear layers that did not remain significant after correction. The correlation between contrast sensitivity and macular thickness, and the electrophysiological measures were not significant after correction. The difference between the high- and low- risk groups correlations was no significant. Conclusions: To our knowledge, this paper is the first of its kind, assessing the relationship between ophthalmological and electrophysiological measures in healthy subjects at distinct levels of risk of AD. The results are novel and unexpected, showing an increase in visual acuity among high-risk subjects, who also exhibit a relationship between this measure and visual-related electrophysiological activity. These results have not been previously explored and could constitute a useful object of research as biomarkers for early detection and the evaluation of potential interventions’ effectiveness.