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Full-Text Articles in Ophthalmology

Retinal Ganglion Cells Underlying Visual Perception And Predation In Mice, Keith Patrick Johnson May 2021

Retinal Ganglion Cells Underlying Visual Perception And Predation In Mice, Keith Patrick Johnson

Arts & Sciences Electronic Theses and Dissertations

The spike trains of retinal ganglion cells (RGCs) are the sole source of visual information to the brain. In mice, more than 40 RGC types send signals to more than 50 brain areas. RGCs that perform nonlinear operations to extract specific visual features (e.g., the motion of an object against a background) are called feature detectors. Those that linearly integrate local changes in light inten-sity are known as pixel encoders. Most mouse RGC types are feature detectors. In the first part of my dissertation, I discovered a pixel encoder RGC type in mice, the PixON-RGC. I revealed how the unique …


Electrophysiology Of The Inner Retina In Health And Disease: Eaat5 In The Rod Bipolar Cell And Oscillatory Potentials In Diabetes, Gregory William Bligard May 2020

Electrophysiology Of The Inner Retina In Health And Disease: Eaat5 In The Rod Bipolar Cell And Oscillatory Potentials In Diabetes, Gregory William Bligard

Arts & Sciences Electronic Theses and Dissertations

The inner retina is a highly tractable location for the study of neural networks in the central nervous system and improving our understanding of the inner retina is important for the treatment of a number of ophthalmic diseases. This dissertation aims to improve understanding of the inner retina in two parts: first, a basic neuroscientific project concerning normal neuronal processing in the inner retina at a cellular level, and second, a translational ophthalmologic project regarding the development in the inner retina of a common disease. In mammals, modulation of the amplitude of dim visual signals primarily occurs at axon terminals …


Understanding The Molecular Pathogenesis Of Retinal Neurodegeneration, Jonathan B. Lin May 2020

Understanding The Molecular Pathogenesis Of Retinal Neurodegeneration, Jonathan B. Lin

Arts & Sciences Electronic Theses and Dissertations

Retinal degenerative diseases are a major cause of morbidity in modern society because visual impairment significantly decreases the quality of life of patients. A significant challenge in treating retinal degenerative diseases is their genetic and phenotypic heterogeneity. Furthermore, limitations in our understanding of disease pathophysiology have led to reliance on therapies that often treat disease endpoints rather than addressing disease etiology and/or pathophysiology. The long-term goal of my thesis research was to provide molecular and cellular insights into the pathophysiology underlying diverse retinal degenerative diseases, which may lead to much-needed, novel therapeutic approaches. During the first part of my thesis …


The Role Of Fibrillin-1 In Eye Development And Disease, Wendell Brooks Jones Dec 2018

The Role Of Fibrillin-1 In Eye Development And Disease, Wendell Brooks Jones

Arts & Sciences Electronic Theses and Dissertations

The ciliary zonule of the human eye consists of a circumferential array of fibers that connect the ocular lens to the nonpigmented ciliary epithelium (NPCE) located at the inner wall of the eye. Zonular fibers consist of bundles of beaded filaments called microfibrils. Microfibrils are major structural elements of the extracellular matrix and are present in pure form in the ciliary zonule. Microfibrils are composed principally of fibrillin-1 (FBN-1); a large extracellular matrix glycoprotein. In humans, mutations in FBN1 underlie Marfan syndrome; a pleiotropic connective tissue disorder that profoundly affects the eye. Ocular manifestations include ectopia lentis (dislocated lenses), cataracts, …


Deciphering Mechanisms Governing The Development Of The Rod Epigenome, Philip Andrew Ruzycki May 2018

Deciphering Mechanisms Governing The Development Of The Rod Epigenome, Philip Andrew Ruzycki

Arts & Sciences Electronic Theses and Dissertations

Precisely coordinated expression of distinct sets of genes is essential for cellular development and function, especially in complex multicellular organisms. This regulation is achieved by the action of transcription factors (TF), proteins that bind specific genomic locations and alter the activity state and packaging of the DNA to promote or repress gene expression. However, while tremendous effort has defined networks of transcription factors that work together to drive specific phenotypes, little is known about their differential activity at the hundreds or thousands of sites where they bind. There are also many questions regarding the basic principles of the packaging of …


Two-Component Hydrogel As Biomimetic Vitreous Substitutes, Sruthi Santhanam Dec 2017

Two-Component Hydrogel As Biomimetic Vitreous Substitutes, Sruthi Santhanam

McKelvey School of Engineering Theses & Dissertations

The vitreous humor of the eye is a biological hydrogel principally composed of fibrillary collagen interspersed with semi-flexible polyelectrolyte, hyaluronic acid (HA). Certain pathological conditions necessitate its removal and replacement. Current vitreous substitutes, such as silicone oils and perfluorocarbons, are hydrophobic, do not resemble the properties of the vitreous, and have known complications. An ideal vitreous substitute should have properties of the natural vitreous, perform its functions, and be biocompatible in the eye. Inspired by the structure and composition of the natural vitreous, we used bio-mimicry to develop an injectable two-component hydrogel. The hydrogel is composed of a fibrillary gellan, …