Person: López Alonso, José Manuel
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First Name
José Manuel
Last Name
López Alonso
Affiliation
Universidad Complutense de Madrid
Faculty / Institute
Óptica y Optometría
Department
Óptica
Area
Optica
Identifiers
7 results
Search Results
Now showing 1 - 7 of 7
Item Multifractal analysis of embryonic eye structures from female mice with dietary folic acid deficiency. Part I: Fractal dimension, lacunarity, divergence, and multifractal spectrum(Chaos, Solitons and Fractals, 2020) Sijilmassi, Ouafa; López Alonso, José Manuel; Río Sevilla, Aurora Del; Barrio Asensio, María Del CarmenThe purpose of this study was to investigate effects of low maternal folic acid (FA) status on many eye structures in embryonic mice using multifractal analysis, a method for describing complex structural patterns. To do this, we used the FracLac plugin for ImageJ to analyse binary digital images of cornea, lens, retina, and vitreous after immunohistochemical analysis using anti-collagen IV or anti-laminin-1 antibodies. The box-counting and gliding box methods were used to generate metrics including the fractal dimension, lacunarity, divergence, and multifractal spectrum distance metrics for each ocular structure. Results were analysed using bootstrap resampling techniques and the Kruskal-Wallis significance test. For all structures and staining methods studied, differences between embryos from control vs FA-deficient females were detectable in lacunarity plots and multifractal spectra, and statistically significant in cornea, lens, retina and vitreous. Multifractal analysis detected even slight differences in tissue textures presumably attributable to altered expression of extracellular matrix molecules.Item Multifractal analysis of embryonic eye structures from female mice with dietary folic acid deficiency. Part II: Fractal dimension, lacunarity, divergence, and multifractal spectrum(Chaos, Solitons and Fractals, 2020) Sijilmassi, Ouafa; López Alonso, José Manuel; Río Sevilla, Aurora Del; Barrio Asensio, María Del CarmenThe aim of this work is to study local changes of fractality in mouse embryonic lens. Embryos were removed from female mice that have been subjected to a diet deficient in folic acid for two and eight weeks. The local change of fractality is studied through the analysis of the Local Connected Fractal Dimension (LCFD) on binarised images of these lenses using FracLac plugin for ImageJ, after immunohistochemical analysis performed using anti-collagen IV or anti-laminin-1. The samples were analysed previously by the authors to locate under and overexpression lens zones of these proteins. The results show that there are variations of the LCFD with respect to control groups. These changes show significant positive correlations with changes in spatial patterns of both proteins expression.Item Multispectral Imaging Method for Rapid Identification and Analysis of Paraffin-Embedded Pathological Tissues(Journal of Digital Imaging, 2023) Sijilmassi, Ouafa; López Alonso, José Manuel; Río Sevilla, Aurora Del; Barrio Asensio, María Del CarmenThe study of the interaction between light and biological tissue is of great help in the identification of diseases as well as structural alterations in tissues. In the present study, we have developed a tissue diagnostic technique by using multispectral imaging in the visible spectrum combined with principal component analysis (PCA). We used information from the propagation of light through paraffin-embedded tissues to assess differences in the eye tissues of control mouse embryos compared to mouse embryos whose mothers were deprived of folic acid (FA), a crucial vitamin necessary for the growth and development of the fetus. After acquiring the endmembers from the multispectral images, spectral unmixing was used to identify the abundances of those endmembers in each pixel. For each acquired image, the final analysis was performed by performing a pixel-by-pixel and wavelength-by-wavelength absorbance calculation. Non-negative least squares (NNLS) were used in this research. The abundance maps obtained for the first endmember revealed vascular alterations (vitreous and choroid) in the embryos with maternal FA deficiency. However, the abundance maps obtained for the third endmember showed alterations in the texture of some tissues such as the lens and retina. Results indicated that multispectral imaging applied to paraffin-embedded tissues enhanced tissue visualization. Using this method, first, it can be seen tissue damage location and then decide what kind of biological techniques to apply.Item Alteration of lens and retina textures from mice embryos with folic acid deficiency: image processing analysis(Graefe's Archive for Clinical and Experimental Ophthalmology, 2019) Sijilmassi, Ouafa; López Alonso, José Manuel; Barrio Asensio, María Del Carmen; Río Sevilla, Aurora DelPurpose: Folic acid (FA) is an essential vitamin for embryonic development. It plays particularly a critical role in RNA, DNA and protein synthesis. On the other hand, the collagen IV and laminin-1 are important proteins during embryonic development. This study was done to find if FA deficiency at a short and a long term in mothers could alter the tissue texture of retina and lens of the progeny. Methods: Collagen IV and laminin-1 were localized by immunohistochemistry in the lens and retina of the FA-deficient embryos. To carry out the image processing, texture segmentation was performed through canny edge detection and Fourier transform (FT). We defined a parameter, the grain size, to describe the texture of the lens and retina. A bootstrap method to estimate the distribution and confidence intervals of the mean, standard deviation, skewness and kurtosis of the grain size has been developed. Results: Analysis through image processing using Matlab showed changes in the grain size between control- and FA-deficient groups in both studied molecules. Measures of texture based on FT exhibited changes in the directionality and arrangements of type IV collagen and laminin-1. Conclusions: Changes introduced by FA deficiency were visible in the short term (2 weeks) and evident in the long term (8 weeks) in both grain size and orientation of fibre structures in the tissues analysed (lens and retina). This is the first work devoted to study the effect of FA deficit in the texture of eye tissues using image processing techniques.Item Biometric Alterations of Mouse Embryonic Eye Structures Due to Short-Term Folic Acid Deficiency(Current Eye Research, 2018) Sijilmassi, Ouafa; López Alonso, José Manuel; Río Sevilla, Aurora Del; Murillo González, Jorge Alfonso; Barrio Asensio, María Del CarmenPurpose: Folic acid (FA) is an essential nutrient for normal embryonic development. FA deficiency (FAD) in maternal diet increases the risk of several defects among the progeny, especially, neural tube defects. The eye begins its development from the neural tube; however, the relationship between FAD and ocular development in the offspring has been little explored and it isn’t known how the FAD affects the formation of the eye. Our objective was to analyze the effect of maternal FAD on mouse embryos ocular biometry. Methods: Female mice C57/BL/6J were distributed into three different groups, according to the assigned diet: control group fed a standard FA diet (2 mg FA/kg), FAD group for short term fed (0 mg FA/kg + 1% succinylsulfathiazole) from the day after mating until day 14.5 of gestation, and FAD group for long term fed the same FA-deficient diet for 6 weeks prior mating and continued with this diet during gestation. A total of 57 embryos (19 embryos of each dietary group) at 14.5 gestational days were evaluated. As indicators of changes in ocular biometry, we analyze two parameters: area and circularity of the lens and whole eye, and the area of the retina. The program used in the treatment and selection of the areas of interest was ImageJ. The statistical analysis was performed by IBM SPSS Statistics 19. Results: Regarding the measures of the area, FA-deficient lenses and eyes were smaller than that of controls. We have also observed increase in the size of the neural retina, spatially, in embryos from females fed FAD diet during long term. On the other hand, as regard to circularity measures, we have seen that eyes and lenses were more circular than control. Conclusion: Maternal FAD diet for a very short term generates morphological changes in ocular structures to the offspring.Item Collagen IV and laminin‐1 expression in embryonic mouse lens using principal components analysis technique(Journal of Microscopy, 2018) Sijilmassi, Ouafa; López Alonso, José Manuel; Barrio Asensio, María Del Carmen; Río Sevilla, Aurora DelImmunohistochemistry section staining is not always easy to interpret. Manual quantification of immunohistochemical staining is limited by the observer visual ability to detect changes in level staining. Hence, the quantification of immunostaining by means of digital image analysis allows us to measure accurately protein expression percentages in immunobiological stained tissues and ensures to overcome the visual limitations. We perform an experimental study to analyse the impact of folic acid (FA) deficiency into collagen IV and laminin‐1 expression in the embryonic mouse lens. The study starts with microscope images of embryos mouse lens whose mothers fed a diet deficient in FA during 2 and 8 weeks. A principal component analysis (PCA) image processing is used to analyse these images coming from control and FA deficit groups. The method permits to define an index of over‐ or infraexpression of collagen IV and laminin‐1 associated to different spatial organisation structures (PC processes). Additionally, it permits to determine in precise percentage the exact quantity of the overexpression or infraexpression and finally to comprehend molecular regionalisation and expression in both control and deficient groups. The results suggest that even with 2 weeks of deficit of FA the expression and distribution of both molecules is affected.Item Development of a polarization imaging method to detect paraffin‐embedded pathology tissues before applying other techniques(Journal of biophotonics, 2020) Sijilmassi, Ouafa; López Alonso, José Manuel; Río Sevilla, Aurora Del; Barrio Asensio, María Del CarmenThe present article describes the development of a technique, applied to paraffin‐embedded tissues, which uses three different wavelengths of monochromatic light (λ1 = 445 nm, λ2 = 540 nm and λ3 = 660 nm) for the measures of the degree of polarization, degree of linear polarization, degree of circular polarization and birefringence, all obtained from measurements of Stokes parameters by using polarized light. The goal of this study was to detect changes in developing embryonic mouse eye when pregnant mice fed diets without folic acid for variable periods compared with a healthy control group. We present a biomedical diagnostic technique based on polarized light detection applied to paraffin‐embedded tissues to visualize the structural damage to aid us in the diagnosis before applying other techniques. Through this method, we can visualize and identify which parts of the tissue were altered with respect to the control group.