Optometry Commons^™

Super-Resolution Microscopy Reveals Photoreceptor-Specific Subciliary Location And Function Of Ciliopathy-Associated Protein Cep290, Valencia L Potter, Abigail R Moye, Michael A Robichaux, Theodore G Wensel

Faculty, Staff and Students Publications

Mutations in the cilium-associated protein CEP290 cause retinal degeneration as part of multiorgan ciliopathies or as retina-specific diseases. The precise location and the functional roles of CEP290 within cilia and, specifically, the connecting cilia (CC) of photoreceptors, remain unclear. We used super-resolution fluorescence microscopy and electron microscopy to localize CEP290 in the CC and in the primary cilia of cultured cells with subdiffraction resolution and to determine effects of CEP290 deficiency in 3 mutant models. Radially, CEP290 localizes in close proximity to the microtubule doublets in the region between the doublets and the ciliary membrane. Longitudinally, it is distributed throughout …

Structure And Dynamics Of Photoreceptor Sensory Cilia, Theodore G Wensel, Valencia L Potter, Abigail Moye, Zhixian Zhang, Michael A Robichaux

Faculty, Staff and Students Publications

The rod and cone photoreceptor cells of the vertebrate retina have highly specialized structures that enable them to carry out their function of light detection over a broad range of illumination intensities with optimized spatial and temporal resolution. Most prominent are their unusually large sensory cilia, consisting of outer segments packed with photosensitive disc membranes, a connecting cilium with many features reminiscent of the primary cilium transition zone, and a pair of centrioles forming a basal body which serves as the platform upon which the ciliary axoneme is assembled. These structures form a highway through which an enormous flux of …

Preventing Ocular Surface Disease In The Pediatric Intensive Care Unit, Emily Mallette

Dissertations

Preventing Ocular Surface Disease in the Pediatric Intensive Care Unit

Problem: Ocular surface disease in the Pediatric Intensive Care Unit is a significant problem in intubated patients due to altered eye protective mechanics, leading to exposure of the eye surface and dry eye. The purpose of this quality improvement project was to evaluate how an eye care protocol affected the frequency of artificial tear ointment administration.

Method: A descriptive, cohort design utilizing a retrospective chart review with convenience sampling of intubated children in the PICU from two cohorts was used. Comparisons were made between the preintervention cohort in 2020 and …

Search For Palladin, An Actin-Associated Protein, In Pig Retinal Pigmented Epithelium And Its Role In Epithelial-Mesenchymal Transition, Katrina Powell

Undergraduate Theses

This study investigates the expression of Palladin, a phosphoprotein product of the PALLD gene, in the retinal pigmented epithelium (RPE). Palladin is an actin cross-linking protein and plays a role in cell adhesion and motility. Published reports have demonstrated that a down regulation of Palladin in colon cancer cells results in a reorganization of the actin cytoskeleton, causing the cells to lose their typical shape, become proliferative and migratory. This process is otherwise known as epithelial-mesenchymal transition (EMT). A similar EMT phenomenon is observed when the RPE is exposed to the vitreous humor in patients with proliferative vitreoretinopathy (PVR). In …

Single-Cell Transcriptomics Identifies Limbal Stem Cell Population And Cell Types Mapping Its Differentiation Trajectory In Limbal Basal Epithelium Of Human Cornea, De-Quan Li, Sangbae Kim, Jin-Miao Li, Qianmiao Gao, Jongsu Choi, Fang Bian, Jiaoyue Hu, Yun Zhang, Jin Li, Rong Lu, Yumei Li, Stephen C Pflugfelder, Hongyu Miao, Rui Chen

Faculty, Staff and Students Publications

PURPOSE: This study aimed to uncover novel cell types in heterogenous basal limbus of human cornea for identifying LSC at single cell resolution.

METHODS: Single cells of human limbal basal epithelium were isolated from young donor corneas. Single-cell RNA-Sequencing was performed using 10x Genomics platform, followed by clustering cell types through the graph-based visualization method UMAP and unbiased computational informatic analysis. Tissue RNA in situ hybridization with RNAscope, immunofluorescent staining and multiple functional assays were performed using human corneas and limbal epithelial culture models.

RESULTS: Single-cell transcriptomics of 16,360 limbal basal cells revealed 12 cell clusters belonging to three lineages. …

Addressing Artificial Intelligence Bias In Retinal Diagnostics, Philippe Burlina, Neil Joshi, William Paul, Katia D Pacheco, Neil M Bressler

Faculty, Staff and Students Publications

PURPOSE: This study evaluated generative methods to potentially mitigate artificial intelligence (AI) bias when diagnosing diabetic retinopathy (DR) resulting from training data imbalance or domain generalization, which occurs when deep learning systems (DLSs) face concepts at test/inference time they were not initially trained on.

METHODS: The public domain Kaggle EyePACS dataset (88,692 fundi and 44,346 individuals, originally diverse for ethnicity) was modified by adding clinician-annotated labels and constructing an artificial scenario of data imbalance and domain generalization by disallowing training (but not testing) exemplars for images of retinas with DR warranting referral (DR-referable) from darker-skin individuals, who presumably have greater …

Identification Of Deep-Intronic Splice Mutations In A Large Cohort Of Patients With Inherited Retinal Diseases, Xinye Qian, Jun Wang, Meng Wang, Austin D Igelman, Kaylie D Jones, Yumei Li, Keqing Wang, Kerry E Goetz, David G Birch, Paul Yang, Mark E Pennesi, Rui Chen

Faculty, Staff and Students Publications

High throughput sequencing technologies have revolutionized the identification of mutations responsible for a diverse set of Mendelian disorders, including inherited retinal disorders (IRDs). However, the causal mutations remain elusive for a significant proportion of patients. This may be partially due to pathogenic mutations located in non-coding regions, which are largely missed by capture sequencing targeting the coding regions. The advent of whole-genome sequencing (WGS) allows us to systematically detect non-coding variations. However, the interpretation of these variations remains a significant bottleneck. In this study, we investigated the contribution of deep-intronic splice variants to IRDs. WGS was performed for a cohort …

Loss Of Class Iii Phosphoinositide 3-Kinase Vps34 Results In Cone Degeneration, Ammaji Rajala, Feng He, Robert E Anderson, Theodore G Wensel, Raju V S Rajala

Faculty, Staff and Students Publications

The major pathway for the production of the low-abundance membrane lipid phosphatidylinositol 3-phosphate (PI(3)P) synthesis is catalyzed by class III phosphoinositide 3-kinase (PI3K) Vps34. The absence of Vps34 was previously found to disrupt autophagy and other membrane-trafficking pathways in some sensory neurons, but the roles of phosphatidylinositol 3-phosphate and Vps34 in cone photoreceptor cells have not previously been explored. We found that the deletion of Vps34 in neighboring rods in mouse retina did not disrupt cone function up to 8 weeks after birth, despite diminished rod function. Immunoblotting and lipid analysis of cones isolated from the cone-dominant retinas of the …

Metachronous Eyelid Basal Cell Carcinoma On Opposite Eye And Lid: A Case Report, Danielle C. Kalberer Od, Faao, Matthew A. Delmauro Md

Optometric Clinical Practice

Background: Basal cell carcinoma (BCC) is the most common eyelid malignancy, accounting for approximately 90% of malignant eyelid lesions.¹ Despite its high occurrence rates, it is frequently misdiagnosed as one of the benign “lumps and bumps” that can be present on the eyelid. In the present case, a patient with a past BCC on the right upper eyelid presented with a left lower eyelid lesion which persisted for months before the patient sought evaluation by an eyecare provider. This benign-looking lash-line lesion was the only external sign of the malignancy found on the deep surface of the eyelid and …

Mtor-Initiated Metabolic Switch And Degeneration In The Retinal Pigment Epithelium, Young-Mi Go, Jing Zhang, Jolyn Fernandes, Christopher Litwin, Rui Chen, Theodore G Wensel, Dean P Jones, Jiyang Cai, Yan Chen

Faculty, Staff and Students Publications

The retinal pigment epithelium (RPE) is a particularly vulnerable tissue to age-dependent degeneration. Over the life span, the RPE develops an expanded endo-lysosomal compartment to maintain the high efficiency of phagocytosis and degradation of photoreceptor outer segments (POS) necessary for photoreceptor survival. As the assembly and activation of the mechanistic target of rapamycin complex 1 (mTORC1) occur on the lysosome surface, increased lysosome mass with aging leads to higher mTORC1 activity. The functional consequences of hyperactive mTORC1 in the RPE are unclear. In the current study, we used integrated high-resolution metabolomic and genomic approaches to examine mice with RPE-specific deletion …

Myopia Outcome Study Of Atropine In Children (Mosaic): Design And Methodology, Saoirse Mccrann, Daniel Ian Flitcroft, John Butler, James Loughman

Articles

Purpose

The Myopia Outcome Study of Atropine in Children (MOSAIC) aims to explore the efficacy, safety, acceptability and mechanisms of action of 0.01% atropine for myopia control in a European population.

Methods

MOSAIC is an investigator-led, double-masked, placebo-controlled, randomised clinical trial investigating the efficacy, safety and mechanisms of action of 0.01% atropine eyedrops in myopic progression management. During phase 1 of the trial, 250 children aged 6-16 years with progressive myopia apply eye drops once nightly in both eyes from randomisation to month 24. No treatment is given during phase 2 from month 24 to 36 (washout period) for those …

Eye Tissue Regeneration: Seam As A Cure For Prevalent Eye Disease, Molly Bute

Biology: Student Scholarship & Creative Works

SEAM (Self-formed ectodermal autonomous multizone) is a form of eye tissue regeneration discovered by Japanese scientists in 2016. This tissue regeneration encompasses tissues from all areas of the human eye. The SEAM forms tissues using stem cells, induced pluripotent stem cells were used in the first study, and produces four concentric zones. The SEAM that has been created was shown to cure corneal blindness in animal models, and has the potential to cure a multitude of human eye diseases in the future.

Latanoprost And Timolol In Hydrogel Soft Drug-Dispensing Contact Lenses: A Comparative Analysis, Neha Potdar

Virginias Collegiate Honors Council Conference

Glaucoma patients only can instill glaucoma eye drops. This results in 1-7% absorption of the medication. Surveys show that patients forget to take their medication and have difficulty inserting their eye drops. Researchers at the Massachusetts Eye and Ear Infirmary have developed latanoprost drug-dispensing hydrogel soft contact lenses that dispense the drug to help facilitate the process. However, some glaucoma patients do not respond to latanoprost because they have uveitic glaucoma or do not want to experience latanoprost’s ocular side effects. Patients need an alternative which can be inserted into these contact lenses. Another commonly used glaucoma drug is timolol …

Efficient In Vitro Development Of Photoreceptors From Human Pluripotent Stem Cells, Joseph C. Reynolds

Dissertations, Masters Theses, Capstones, and Culminating Projects

Degeneration of the rod and cone photoreceptors in the human retina is among the most common causes of blindness. Replacing these damaged photoreceptors may help to restore vision. Repairing the damaged retina relies on the insertion of new, healthy cells. Embryonic stem (ES) cells and induced pluripotent stem (iPS) cells are two possible sources of photoreceptors to restore vision. Previous data shows that human ES cells and iPS cells can be differentiated into photoreceptors and transplanted into the eye to restore some vision. However, this process is inefficient, and costly. Here, we show a new method for inducing photoreceptor production …

Visual Performance, And It's Response To Intervention, In Subjects With Age-Related Macular Degeneration., Sarah Sabour-Pickett

Doctoral

Abstract Objectives: 1. To explore visual performance status through a range of psychophysical methods beyond corrected distance visual acuity (CDVA), in subjects with age-related macular degeneration (AMD). 2. To investigate the effects on these visual performance parameters in subjects with neovascular age-related macular degeneration (nv-AMD) and in subjects with early AMD undergoing anti-VEGF (vascular endothelial growth factor) therapy and macular carotenoid supplementation, respectively. 3. To understand the role of a supplement containing meso-zeaxanthin (MZ; the third, and currently least explored, macular carotenoid) on the augmentation of macular pigment (MP), on visual performance and on disease progression (graded according to the …

Addressing The Burden Of Uncorrected Refractive Error In Mozambique, Stephen Thompson, James Loughman, Prasidh Ramson, Luigi Bilotti, Geoff Harris, Kovin Naidoo

Conference Papers

A situational analysis indicates a lack of eye health personnel who can and do refract. The logical course of action would be to train more eye health personnel. A conservative estimated annual burden of URE in lost productivity in Mozambique is $14,486,692. To achieve the V2020 target ratio, an extra 184 workers are needed in six provinces analysed.The analysis assumes the existing personnel are well trained and dedicate time to offering a refraction service. It also assumes that the patient receives the care they require. Other aspects of the situational analysis suggest this is currently not always the case. A …

A Study Of Eighty-Three Cases Of Glaucoma Treated By Cyclodiathermy With Reference To The Facility Of Outflow, Robert V. Shearer

Loma Linda University Electronic Theses, Dissertations & Projects

[Abstract Not Included]

Introduction

This study is an attempt to discover the mode of action and evaluate the effectivity of cyclodiathermy in the treatment of glaucoma, using the Muller electric tonometer in studies on the facility of outflow.

This series of cases represents a cross section of the advanced cases of glaucoma which were operated on by attending and resident staff at the White Memorial Hospital between January 1953, and December 1955. Eighty-nine operations were performed on eighty-three eyes of fifty-eight patients of whom, with but few exeptions [sic], had lost field in the poorer eye to less than five …