Purpose: The purpose of this study is to develop methods to identify glaucoma by examining the optic nerve head (ONH) of donor's eyes when information on the preexisting ocular disease is unavailable.
Materials And Methods: The ONH of the donor's eyes was evaluated under a stereomicroscope for the cup-disc ratio (CDR) and focal retinal rim thinning. The vertical diameter of the cup and disc was also measured using a precalibrated eyepiece micrometer. The suspect eyes were subjected to histological analysis to confirm the presence of specific glaucomatous changes.
Results: A total of 202 eyes from 119 donors (68 males and 51 females, aged 42-96) were evaluated for glaucoma. Among them, 190 (94%) eyes showing vertical CDR in the of 0.0-0.6 range were considered nonglaucomatous and the remaining eyes with >0.6 as glaucoma suspect. The calculated mean CDR of the two groups (0.3 ± 0.16, 0.62 ± 0.27) was highly significant (P = 0.0003). Of 12 eyes suspected of glaucoma, 7 eyes from 5 donors showed specific glaucomatous changes by histology. The prevalence of glaucoma was 4.2% among the donors studied.
Conclusions: A simple method of screening fresh donor eyes for selecting those with glaucoma features using CDR and histological analysis was reported. This method helps to obtain biologically active human ocular tissue for glaucoma research on gene expression, ultrastructural/proteome changes, and outflow mechanism.
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http://dx.doi.org/10.4103/0301-4738.167118 | DOI Listing |
Biomed Phys Eng Express
January 2025
Department of Ophthalmology, Hospital Universitario de Canarias, Carretera Ofra S/N, La Laguna, Santa Cruz de Tenerife, 38320, SPAIN.
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January 2025
Section on Perception, Cognition, Action, Laboratory of Sensorimotor Research, National Eye Institute, NIH, Bethesda, MD 20892.
To what extent does concept formation require language? Here, we exploit color to address this question and ask whether macaque monkeys have color concepts evident as categories. Macaques have similar cone photoreceptors and central visual circuits to humans, yet they lack language. Whether Old World monkeys such as macaques have consensus color categories is unresolved, but if they do, then language cannot be required.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Brain Sciences, Weizmann Institute of Science, Rehovot 7610001, Israel.
Retinal ganglion cells (RGCs) typically respond to light stimulation over their spatially restricted receptive field. Using large-scale recordings in the mouse retina, we show that a subset of non- direction-selective (DS) RGCs exhibit asymmetric activity, selective to motion direction, in response to a stimulus crossing an area far beyond the classic receptive field. The extraclassical response arises via inputs from an asymmetric distal zone and is enhanced by desensitization mechanisms and an inherent DS component, creating a network of neurons responding to motion toward the optic disc.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Biology and Biological Engineering, California Institute of Technology, Pasadena, CA 91125.
Cognition relies on transforming sensory inputs into a generalizable understanding of the world. Mirror neurons have been proposed to underlie this process, mapping visual representations of others' actions and sensations onto neurons that mediate our own, providing a conduit for understanding. However, this theory has limitations.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
January 2025
Department of Cell & Developmental Biology, School of Biological Sciences, University of California San Diego, La Jolla, CA 92093.
A spectacular diversity of forms and features allow species to thrive in different environments, yet some structures remain relatively unchanged. Insect compound eyes are easily recognizable despite dramatic differences in visual abilities across species. It is unknown whether distant insect species use similar or different mechanisms to pattern their eyes or what types of genetic changes produce diversity of form and function.
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