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Full-Text Articles in Optometry
Differential Recruitment Of Bone Marrow-Derived Cells Into The Injured Retina, Bright Asare-Bediako
Differential Recruitment Of Bone Marrow-Derived Cells Into The Injured Retina, Bright Asare-Bediako
All ETDs from UAB
The hematopoietic system, which resides in the bone marrow in adults, maintains the constant turnover of blood cells in the circulatory system and supplies inflammatory/vascular reparative cells to the retina. Chronic metabolic diseases disrupt hematopoietic homeostasis, suppressing the generation of bone marrow-derived reparative cells in favor of pro-inflammatory cells. While much research has been done on development and disease-associated changes in hematopoiesis in the long bones and how mobilization to the retina is affected, the calvarium's hematopoiesis is underexplored. This dissertation investigated hematopoiesis in postnatal development and in disease, comparing calvarium hematopoiesis to that of long bones. The findings showed …
Neural-Glial-Vascular Interactions In Human Outer Retina, Deepayan Kar
Neural-Glial-Vascular Interactions In Human Outer Retina, Deepayan Kar
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The outer retinal metabolic ecosystem is a complex interplay among photoreceptors, RPE and blood supply from the retinal and choroidal microcirculation. Breakdown of any component of this ecosystem has detrimental effects and can lead to cellular dysfunction. For example, in age-related macular degeneration a major cause of vision loss in older adults, breakdown of this metabolic unit has severe structural and functional implications. Thus, every feature and component of this ecosystem seems to be optimized to protect non-replicating, terminally differentiated cells from being damaged. Remarkably, much of the cellular and subcellular organization of this system is available for observation in …
Towards Minimally Invasive Genetically Targeted Control Of Neural Activity Using X-Rays, Kelli Cannon
Towards Minimally Invasive Genetically Targeted Control Of Neural Activity Using X-Rays, Kelli Cannon
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X-genetics aims to replace visible light stimulation in optogenetics with X-radiation, offering improved bone penetration, minimal scattering, and enhanced targeting capabilities. This eliminates the need for surgical optic fiber implantation, reducing invasiveness and minimizing off-target effects. Discovering a receptor protein sensitive to X-rays or their byproducts is pivotal for advancing X-genetics.Two genetically encoded X-ray receptors (GEXRs) were investigated for X-genetics application: rhodopsin, historically associated with X-ray responses, and LITE-1, an unexpected candidate. Rhodopsin, when expressed in human embryonic kidney (HEK293) cells, demonstrated robust cAMP decreases upon visible light stimulation but remained unresponsive to moderate and high-dose X-rays, suggesting it may …
Intrinsically-Photosensitive Retinal Ganglion Cells And Their Functional Roles, Kevin Q. Chang
Intrinsically-Photosensitive Retinal Ganglion Cells And Their Functional Roles, Kevin Q. Chang
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This project was conducted in Old World monkeys and focused on characterization of the intrinsically photosensitive retinal ganglion cells (ipRGCs) as they pertain to the pupillary light reflex, as well as on the neuroanatomical and electrophysiological characterization of the suprachiasmatic nucleus (SCN) of the hypothalamus as it pertains to circadian rhythms. A custom antibody was developed against the human melanopsin gene. We validated the antibody using western blot and immunohistochemistry. The functional role of ipRGCs in driving pupillary responses was investigated through immunotoxin-induced ablation in Rhesus macaques with the antibody conjugated to saporin. As hypothesized, the pupillary light reflex and …
The Effect Of Training On Eye Movement While Learning To Use A Non-Foveal Retinal Locus, Jason Eugene Vice
The Effect Of Training On Eye Movement While Learning To Use A Non-Foveal Retinal Locus, Jason Eugene Vice
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Vision is our most far-reaching sense. It allows us to quickly detect information about the environment and enhances our ability to interact with the world around us. Accordingly, many neural areas are devoted to obtaining, processing, and interpreting visual information. When vision is impaired through normal aging or disease processes, the functional implications for a person can be quite significant. This is particularly true when a person is deprived of high acuity, central vision. Many people with bilateral central visual impairments learn to compensate for vision loss by adopting a viewing strategy that involves the use of the peripheral retina. …
The Use Of Vesgen For Analysis Of Retinal Vasculature In Pulmonary Arterial Hypertension, Mariana Desiree Dupont
The Use Of Vesgen For Analysis Of Retinal Vasculature In Pulmonary Arterial Hypertension, Mariana Desiree Dupont
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Pulmonary artery hypertension is a chronic and progressive disease leading to right heart failure and, ultimately, death if untreated. The goal of the studies in this dissertation was to determine if fluorescein angiography (FA), and color fundus angiography (CF) imaging could be used to garner critical information about retinal changes in individuals with pulmonary artery hypertension (PAH). VESsel GENerational Analysis (VESGEN) is a noninvasive computer program that assigns branching generation to large and small vessels. VESGEN was utilized to investigate vascular alterations in FA, and CF imaging investigating disease progression in PAH. This dissertation demonstrated that PAH patients had aberrant …
Glycoprotein 340 Expression In Dry Eye Disease And Ocular Surface Infection, Kwaku Antwi Osei
Glycoprotein 340 Expression In Dry Eye Disease And Ocular Surface Infection, Kwaku Antwi Osei
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Glycoprotein 340 (Gp340) is a 340-kDa multi-domain pattern recognition receptor (PRR) belonging to the scavenger receptor cysteine-rich superfamily of proteins. On the ocular surface, Gp340 is expressed in the tear film, lacrimal gland, cornea, and conjunctiva. By their nature, PRRs detect pathogen-associated molecular patterns (PAMPs) on microbial organisms and damage-associated molecular patterns (DAMPs) released from injured, stressed, necrotic, and apoptotic cells. This, in turn, induces the expression of nuclear factor-κB- and the interferon regulatory factor-dependent expression proinflammatory cytokines and chemokines, eliciting both innate and adaptive immune response activation. Thus, as a PRR, Gp340 has the potential to modulate microbial infection …
Patterns Of Medication Adherence In Glaucoma, Shervonne Poleon
Patterns Of Medication Adherence In Glaucoma, Shervonne Poleon
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Over 60 million persons globally are affected by primary open angle glaucoma (POAG)—an optic neuropathy characterized by distinctive patterns of vision loss. Glaucoma is a leading cause of irreversible blindness worldwide, and eye drops that delay vision loss are a common treatment modality. In glaucoma, the proportion of patients with good adherence to recommended therapy is reported to be low. High treatment cost, forgetfulness, and regimen complexity have been identified as key determinants of poor adherence. However, addressing these factors in the clinic is not as simple, as patient and provider values and priorities may differ. Without concordance, it can …
Color Vision Testing With Readily Available Materials, Angel Perez
Color Vision Testing With Readily Available Materials, Angel Perez
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COLOR VISION TESTING WITH READILY AVAILABLE MATERIALS ANGEL PEREZ VISION SCIENCE ABSTRACT The perception of color is a process by which the brain discriminates different light wavelengths stimulating the cone photoreceptors in the retina of the eye. In humans each cone contains a photopigment making it most sensitive to either short (red), medium (green), or long (blue) wavelengths of light. However, when one of the cone pigments is defective or missing, color discrimination is reduced, resulting in color vision deficiency due to a deficient sex-linked chromosome in most cases. Color vision deficiency has the potential to impede many everyday activities, …
Developing An Assessment Of Reading Impairment And Its Impact On Occupational Performance In Older Adults With Glaucoma In A Metropolitan Area Of The Southeastern Us: A Mixed Methods Approach, Robin Deacy
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According to the United States Administration on Aging (AOA, 2014), the population of individuals over 65 will be 98 million by the year 2060, doubling its 2014 estimates. As our population ages, the prevalence of glaucoma increases. Vision loss resulting from glaucoma can limit participation in valued occupations including engagement in reading. It has long been thought that mobility issues and glare sensitivity were the main factors that characterized glaucoma. In the late 1990s and early 2000s researchers began to examine quality of life (QoL) in those with glaucoma. It was during these early QoL studies that the first reports …
Quality Of Life, Reading And Accommodation In Children With Low Vision, Dawn Kissner Decarlo
Quality Of Life, Reading And Accommodation In Children With Low Vision, Dawn Kissner Decarlo
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Childhood permanent, uncorrectable vision impairment (VI) is rare, yet it is a public health burden as the impairment lasts a lifetime. Vision impairment describes decreased vision that affects everyday activities. Acuity cut-points commonly used include 20/40, 20/60 or 20/70. Blindness often refers to legal blindness (best corrected visual acuity of 20/200 or worse or a visual field less than 20 degrees). Children with VI often have hereditary conditions such as albinism, optic atrophy and retinal degenerations and are different in many ways than adults with VI. The majority have conditions with onset at or near birth and as a result …
Toward The Mechanism Underlying Latanoprost- And Benzalkonium Chloride-Induced Meibomian Gland Dysfunction In Patients Treated For Glaucoma, Jillian Ziemanski
Toward The Mechanism Underlying Latanoprost- And Benzalkonium Chloride-Induced Meibomian Gland Dysfunction In Patients Treated For Glaucoma, Jillian Ziemanski
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Once thought to be no more than a vexing eye condition, ocular surface disease (OSD) is now being viewed as a differentiating factor between sight and no sight. In the setting of glaucoma, OSD can interfere with treatment success, potentially allowing the visually devastating pathology of glaucoma to plow onward with little restraint. Compounding the clinical challenge is the growing awareness that glaucoma-associated OSD appears to be iatrogenically induced by topical ophthalmic medications. Daily, topical instillation of preserved prostaglandin analogs (PGAs), the most common first-line treatment for glaucoma, has been linked to a variety of OSD subtypes, including meibomian gland …
Characterization Of Intraocular Pressure Fluctuations, Intracranial Pressure And Translaminar Pressure Measured With Wireless Telemetry In Nonhuman Primates, Jessica Violet Jasien
Characterization Of Intraocular Pressure Fluctuations, Intracranial Pressure And Translaminar Pressure Measured With Wireless Telemetry In Nonhuman Primates, Jessica Violet Jasien
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Glaucoma is the second leading cause of blindness and third leading cause of visual impairment worldwide; 180 million people suffer from a glaucomatous visual disability. Glaucoma is an ocular neurodegenerative disease with several risk factors. The major identified risk factors of glaucoma are intraocular pressure (IOP), age, race, central cornea thickness, family history, and low diastolic blood pressure. The lowering of IOP is the only modifiable risk factor for the disease. However, we know little about the true character of IOP. Periodic IOP measurements are obtained every few months or at the discretion of the clinician during office hours and …
Role Of Trib3 In Progression And Pathogenesis Of Diabetic Retinopathy, Priyamvada Milind Pitale
Role Of Trib3 In Progression And Pathogenesis Of Diabetic Retinopathy, Priyamvada Milind Pitale
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Diabetic retinopathy (DR) is reported to be one of the leading causes of blindness in the United States by Center for Disease Prevention and Control. As the estimated prevalence of the disease will likely triple by 2020, the research in this area should focus on identifying novel targets and therapeutic approaches. One of the therapeutic approaches for DR is the reprograming of retinal metabolism to delay the progression of the disease. The unfolded protein response (UPR) is recognized as a cellular pathway activated in diabetic retina which interacts with key transcription factors to physiologically regulate glucose, lipid homeostasis, and angiogenic …
Intraocular Pressure Dynamics, Daniel Coleman Turner
Intraocular Pressure Dynamics, Daniel Coleman Turner
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While cataracts (the leading cause of blindness worldwide) can be reversed surgical-ly, glaucoma is the leading cause of irreversible blindness, affecting over 70 million people worldwide [1]. Elevated intraocular pressure (IOP) and age are the primary risk factors for glaucoma [2] and lowering IOP is the only proven treatment for the disease [3]. IOP and its fluctuations affect nearly every aspect of ocular physiology and homeo-stasis, as well as playing a dominant role in glaucoma pathophysiology, yet very little is known about IOP due to the current clinical standard of measuring mean IOP during infre-quent clinic visits. We use a …
The Role Of Protein Synthesis Attenuation And Eif2-Alpha Phosphorylation In Retinal Degeneration, Christopher Ryan Starr
The Role Of Protein Synthesis Attenuation And Eif2-Alpha Phosphorylation In Retinal Degeneration, Christopher Ryan Starr
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Inherited retinal degeneration is a class of diseases in which there is no cure and very few treatment options available. An activated unfolded protein response has been detected in various animal models of retinal degenerative diseases. Several groups have found heightened activation of one pathway of the unfolded protein response in particular, the protein kinase R-like endoplasmic reticulum kinase signaling cascade, which converges on and phosphorylates the alpha subunit of eukaryotic translation initiation factor 2 to transiently halt protein synthesis and allow the cell to reestablish homeostasis. Although it is widely accepted that this signaling is inherently protective, hyperactivity or …
The Closed Eye As A Model For Dry Eye Disease, Cameron Kenneth Postnikoff
The Closed Eye As A Model For Dry Eye Disease, Cameron Kenneth Postnikoff
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Every night, during sleep, the tears of the closed eye become significantly more inflammatory, with a notable influx of neutrophils. Preliminary studies suggested that these neutrophils were significantly different than blood-isolated neutrophils, with an increased concentration, upregulated surface expression of inflammatory membrane receptors, but inability to respond to inflammatory stimuli. The purpose of this dissertation was to better understand the contribution of this neutrophil population to ocular surface homeostasis and dry eye disease. Chapter One presents an introduction to the tear film and ocular surface, along with an introduction to dry eye disease and neutrophil biology. Chapter One also discusses …
Characterization Of Membrane Associated Mucins In Ocular Surface Disease, Anna Ablamowicz
Characterization Of Membrane Associated Mucins In Ocular Surface Disease, Anna Ablamowicz
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Mucins on the ocular surface are found in the tear film and are attached to corneal and conjunctival epithelial cells on the eye. The bulbar conjunctiva of the ocular surface can be divided into four anatomical regions: temporal, superior, nasal, and inferior. The palpebral conjunctiva is the epithelial layer of the inner surfaces of the upper and lower eyelids. In the tears, mucins provide lubrication of the ocular surface through formation of a hydrophilic gel. The primary mucin in the tear film is MUC5AC which is secreted by goblet cells that are located in varying densities within the bulbar conjunctiva. …
Connecting Cilium Proteins Bbs5 And Mks6 And Their Roles In Retinal Degeneration, Katie Leigh Bales
Connecting Cilium Proteins Bbs5 And Mks6 And Their Roles In Retinal Degeneration, Katie Leigh Bales
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The primary cilium is an evolutionary conserved structure with numerous motility and sensory-related functions, dynamically concentrating signaling molecules to developmental, homeostatic and sensory pathways. Rod and cone photoreceptor cells are highly modified primary cilia, which reside in the back of the eye within the neural retina and are responsible for dim light sensitivity and visual acuity/ color vision, respectfully. These cells require massive protein production and proper protein trafficking on a daily basis. The major protein complexes that govern protein trafficking within photoreceptors form the connecting cilium, are the transition zone which serves as a gatekeeper, regulating protein trafficking into …
Morphological And Functional Characterization Of A Murine Garp2-Specific Knockout, Delores Stacks
Morphological And Functional Characterization Of A Murine Garp2-Specific Knockout, Delores Stacks
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GARP2, found exclusively in retinal rod photoreceptors, has been proposed to function as a structural protein, a calcium binding protein, and a modulator of the phosphodiesterase regulating visual phototransduction cascade kinetics. GARP2 is a splice variant of the Cngb1 gene which also encodes the β-subunit of the phototransduction cyclic nucleotide-gated cation channel and another glutamic acid-rich protein, GARP1. Mutations of the β-subunit and, recently discovered regions shared with the GARP en-coding regions of Cngb1cause retinitis pigmentosa (RP), while overexpression of GARP2 in the absence of the β-subunit accelerates the observed Cngb1-mediated retinal degeneration in mouse β-subunit knockout disease models. In …
The Eye As A Window To The Alzheimer’S Disease Brain, Fred Souza
The Eye As A Window To The Alzheimer’S Disease Brain, Fred Souza
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Alzheimer’s disease (AD) is a debilitating, and the most prevalent, type of dementia that is manifested by cognitive deficits, anomalous protein metabolism, cell loss, and pathological alterations in several neurotransmitter systems, particularly the cholinergic and glutamatergic systems. Moreover, AD is associated with visual deficits that have been reported to occur even in the early stages of the disease and may precede conspicuous cognitive impairment. To date, the underlying causes of the visual deficits and whether they stem from retinal or cortical abnormalities remain poorly understood. The following studies aimed at establishing whether the pathological changes observed in the cerebrum are …
Lipid Biomarkers And Pathway Identification For Contact Lens Related Discomfort, Shyam Panthi
Lipid Biomarkers And Pathway Identification For Contact Lens Related Discomfort, Shyam Panthi
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The purpose of this investigation was to identify possible lipid biomarkers that are associated with contact lens related discomfort and determine whether inflammation as a result of lipid peroxidation or enzymatic arachidonic acid metabolism is associated with such discomfort. Ten microliters of tears were collected from each eye of fifteen subjects (11 non-contact lens wearers, 2 contact lens wearers with discomfort and 2 contact lens wearers without discomfort) and assayed using various chemical extraction methods and mass spectrometry based analytical approaches. This was done to determine whether lipid mediators of inflammation could be identified in low volume (10 l) of …
Oxygen Permeability (Dk) Of Silicone-Hydrogel Materials: Relationship With Water, Silicon, And Fluorine Contents, Terin E. Dupre
Oxygen Permeability (Dk) Of Silicone-Hydrogel Materials: Relationship With Water, Silicon, And Fluorine Contents, Terin E. Dupre
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To more precisely determine the fundamental relationships between oxygen permeability (Dk), water content (WC), silicon (Si) content, and fluorine (F) content of clinically prescribed silicone-hydrogel (SiHy) materials, identical methodologies for 16 commercially available brands of SiHy materials were performed. Dk and WC were determined according to the ANSI and ISO standards and, with Si and F contents, on the same lot numbers of samples across a common range of available refractive powers. A negative linear relationship was found between Si content and water content. Lotrafilcon A, Lotrafilcon B, and the bulk polymer of Delefilcon A initially deviated from this relationship. …
Chromatic Sensitivity: A New Insight Into Color Discrimination, Micah Jason Kinney
Chromatic Sensitivity: A New Insight Into Color Discrimination, Micah Jason Kinney
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Color discrimination varies between individuals even in the absence of a congenital color vision defect. Attempts to explain this variation have shown no link to macular pigment optical density, L:M cone ratios, non-verbal IQ, or female carriers of color vision deficiencies. This study examined individuals’ relative luminance and color-opponent systems sensitivity to their Farnsworth-Munsell 100-Hue (FM-100) color discrimination ability. Thirty normal color vision subjects performed FM-100 and increment threshold testing for white, blue, green and red on a 150 cd/m2 white background. White increment thresholds were compared to colored increment thresholds to produce a luminance to color-opponent system sensitivity ratio …
Elementary Photoreceptor Signaling In Human Vision, Kady Scarlett Bruce
Elementary Photoreceptor Signaling In Human Vision, Kady Scarlett Bruce
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To perceive a spot of light at photopic threshold, a minimum number of photons must be absorbed by cone photoreceptors. While many factors affecting psychophysical threshold have been studied, few have been examined at the single-cone level. Here we reveal how variation in synaptic weighting and signal integration among cones in the human retina occurs in vivo. Using an adaptive optics scanning laser ophthalmoscope (AOSLO) equipped with stimulation capabilities, we targeted cone-sized stimuli to single cones. Perceptual increment thresholds were measured from individual cones and cone pairs in 7 subjects using a Bayesian-based staircase method of threshold estimation. In 42 …
Histopathology And Image Validation Of Outer Retinal Tubulations In Age-Related Macular Degeneration, Katie M. Litts
Histopathology And Image Validation Of Outer Retinal Tubulations In Age-Related Macular Degeneration, Katie M. Litts
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High-resolution imaging of the retina using spectral domain optical coherence tomography (SD-OCT) and adaptive optics scanning laser ophthalmoscopy (AOSLO) is revealing new information about photoreceptor degeneration in age-related macular degeneration (AMD) and other diseases impacting rod and cone photoreceptors. By SD-OCT, the hyperreflective outer retinal bands are visible due to the precise vertical compartmentalization and horizontal alignment of outer retinal cells and tissues (Müller cells, photoreceptors, RPE, and Bruch’s membrane). Validating these bands with normal eyes is difficult because the outer retina is very delicate making accurate histology requiring attached retina and vertically aligned photoreceptors challenging. Conversely, the bands are …
Predictive Modeling Of Ocular Surface Disease States Using Multiple Inflammatory Biomarkers, John L. Bradley
Predictive Modeling Of Ocular Surface Disease States Using Multiple Inflammatory Biomarkers, John L. Bradley
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ABSTRACT Purpose The aim of this study was to adapt conjunctival impression cytology (CIC) and RNA isolation and processing procedures for gene expression analysis of ocular surface inflammatory biomarkers. The RNA yield and quality should be sufficient to enable quantitative real-time PCR of no less than 12 key target genes, with the goal of differentiating among dry eye groups. This study used the optimized inflammatory biomarker gene expression assay in a patient study to identify differences between dry eye and control participants. Materials and Methods CIC was used to collect conjunctival surface cells from 53 qualifying dry eye and control …
The Unfolded Protein Response And Calcium Dysregulation In Autosomal Dominant Retinitis Pigmentosa Animal Models., Vishal Madhukar Shinde
The Unfolded Protein Response And Calcium Dysregulation In Autosomal Dominant Retinitis Pigmentosa Animal Models., Vishal Madhukar Shinde
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The photoreceptor cell death in autosomal dominant retinitis pigmentosa (ADRP) is associated with molecular changes that occur due to mutations in a specific gene. S334ter RHO and P23H RHO are two ADRP rat models expressing mutant rhodopsin. The unfolded protein response (UPR) is a cellular stress response involved in the pathophysiology of several retinal disorders including P23H RHO rats. Considering our previous findings, we started our investigation by examining the status of UPR in S334ter RHO rats. As UPR tightly regulates several signaling pathways, we further studied whether UPR activation in S334ter and P23H RHO retina is accompanied by the …
Modulation Of The Unfolded Protein Response To Delay Apoptosis In An Autosomal Dominant Retinitis Pigmentosa Animal Model, Yogesh Bhootada
Modulation Of The Unfolded Protein Response To Delay Apoptosis In An Autosomal Dominant Retinitis Pigmentosa Animal Model, Yogesh Bhootada
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Retinitis pigmentosa (RP) is a group of retinal degenerative diseases characterized by the loss of rod photoreceptor cells that can be followed by cone degeneration eventually culminating in total photoreceptor cell loss. This disease affects approximately 1.5 million people worldwide and can be transmitted in an autosomal dominant (ADRP) manner accounting for nearly 30% of all RP cases. Dominant rhodopsin mutations have been divided into class I and class II based on the folding of rhodopsin protein, thermal stability, and chromophore regeneration. A threonine-17-methionine (T17M) mutation in rhodopsin is a class II mutation, characterized by a thermal instability/folding defect and …
Transferring Virtual Reality Training To Real World Settings In Individuals With Low Vision And Dual-Sensory Impairments, Ellen Lambert Bowman
Transferring Virtual Reality Training To Real World Settings In Individuals With Low Vision And Dual-Sensory Impairments, Ellen Lambert Bowman
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TRANSFERRING VIRTUAL REALITY TRAINING TO REAL WORLD SETTINGS IN INDIVIDUALS WITH LOW VISION AND DUAL-SENSORY IMPAIRMENTS ELLEN LAMBERT BOWMAN VISION SCIENCE GRADUATE PROGRAM ABSTRACT The goal of this study was to determine if individuals with low vision could learn useful visual skills in Virtual Reality and could transfer these skills to the real world. To achieve this goal, one set of Orientation & Mobility (O&M) skills, using the near lane parallel traffic surge to decide the safest timing to cross a signal controlled street, was selected. Twelve participants with vision too poor to use pedestrian signals were randomly assigned to …