Ophthalmology Commons^™

Fibrosis-The Tale Of H3k27 Histone Methyltransferases And Demethylases, Morgan D. Basta, Svetlana Petruk, Alexander Mazo, Janice L. Walker

Department of Biochemistry and Molecular Biology Faculty Papers

Fibrosis, or excessive scarring, is characterized by the emergence of alpha-smooth muscle actin (αSMA)-expressing myofibroblasts and the excessive accumulation of fibrotic extracellular matrix (ECM). Currently, there is a lack of effective treatment options for fibrosis, highlighting an unmet need to identify new therapeutic targets. The acquisition of a fibrotic phenotype is associated with changes in chromatin structure, a key determinant of gene transcription activation and repression. The major repressive histone mark, H3K27me3, has been linked to dynamic changes in gene expression in fibrosis through alterations in chromatin structure. H3K27-specific homologous histone methylase (HMT) enzymes, Enhancer of zeste 1 and 2 …

Autophagy Requirements For Eye Lens Differentiation And Transparency, Lisa Brennan, M Joseph Costello, J Fielding Hejtmancik, A. Menko, S Amer Riazuddin, Alan Shiels, Marc Kantorow

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Recent evidence points to autophagy as an essential cellular requirement for achieving the mature structure, homeostasis, and transparency of the lens. Collective evidence from multiple laboratories using chick, mouse, primate, and human model systems provides evidence that classic autophagy structures, ranging from double-membrane autophagosomes to single-membrane autolysosomes, are found throughout the lens in both undifferentiated lens epithelial cells and maturing lens fiber cells. Recently, key autophagy signaling pathways have been identified to initiate critical steps in the lens differentiation program, including the elimination of organelles to form the core lens organelle-free zone. Other recent studies using ex vivo lens culture …

Retained Lens Fragment Presenting 32 Years After Cataract Extraction, Thomas Tien, Marcos A Crespo, Tatyana Milman, Zeba Syed

Wills Eye Hospital Papers

Purpose: To report a patient with retained lens material presenting over three decades after initial cataract extraction with fluctuating corneal edema and intraocular inflammation.

Observations: A 66-year-old man presented with a first episode of decreased vision and photophobia 32 years after cataract extraction without intraocular lens implantation in the right eye. Slit lamp examination revealed a tan-colored oblong mass in the inferior angle, in addition to corneal edema and an anterior chamber reaction. The patient was aphakic with traumatic mydriasis, and accordingly it was noted that the mass shifted location between anterior and posterior chambers over subsequent evaluations. The anterior …

Immortal Plain Gut Sutures: A Case Report, Hannah J. Anderson, Kathryn Lynn, Raziyeh Mahmoudzadeh, Tatyana Milman, Manish Jain, Sunir J Garg

Wills Eye Hospital Papers

Purpose: We report the case of a 79-year-old male who presented with irritation and foreign body sensation due to the subconjunctival plain gut sutures that did not dissolve three years after undergoing pars plana vitrectomy (PPV) for macular hole repair.

Observation: A 79-year-old male presented with foreign body sensation and irritation in his left eye. On slit lamp examination, the source of the foreign body sensation was two apparently intact plain gut sutures were visible under the conjunctiva, nasal and temporal to the cornea. These plain gut sutures were placed at the conclusion of PPV surgery three years prior to …

Microtubule-Associated Protein 1 Light Chain 3b, (Lc3b) Is Necessary To Maintain Lipid-Mediated Homeostasis In The Retinal Pigment Epithelium., Anuradha Dhingra, Brent A Bell, Neal S. Peachey, Lauren L. Daniele, Juan Reyes-Reveles, Rachel C. Sharp, Bokkyoo Jun, Nicolas G. Bazan, Janet R. Sparrow, Hye Jin Kim, Nancy J. Philp, Kathleen Boesze-Battaglia

Department of Pathology, Anatomy, and Cell Biology Faculty Papers

Like other neurons, retinal cells utilize autophagic pathways to maintain cell homeostasis. The mammalian retina relies on heterophagy and selective autophagy to efficiently degrade and metabolize ingested lipids with disruption in autophagy associated degradation contributing to age related retinal disorders. The retinal pigment epithelium (RPE) supports photoreceptor cell renewal by daily phagocytosis of shed photoreceptor outer segments (OS). The daily ingestion of these lipid-rich OS imposes a constant degradative burden on these terminally differentiated cells. These cells rely on Microtubule-Associated Protein 1 Light Chain 3 (LC3) family of proteins for phagocytic clearance of the ingested OS. The LC3 family comprises …

Lacrimal Gland Tumors In Turkey: Types, Frequency, And Outcomes., Yağmur Seda Yeşiltaş, Ahmet Kaan Gündüz, Esra Erden, Carol L. Shields

Wills Eye Hospital Papers

AIM: To evaluate the clinical, radiological, and treatment features of lacrimal gland tumors.

METHODS: Retrospective review of 99 eyes of 92 patients with lacrimal gland tumors diagnosed and managed in a single institution between January 1999 and March 2017. Clinical and radiological features, histopathology, treatment methods, and prognosis were evaluated.

RESULTS: The mean patient age was 40.3 (range: 7-80)y. The diagnosis was made histopathologically in 91 (91.9%) tumors and on a clinical and radiological basis in 8 (8.1%) tumors. Final diagnoses included idiopathic orbital inflammation (pseudotumor) in 46 (46.5%) lesions, pleomorphic adenoma in 14 (14.1%), adenoid cystic carcinoma in 12 …

GabaB Receptor Attenuation Of GabaA Currents In Neurons Of The Mammalian Central Nervous System, Wen Shen, Changlong Nan, Peter T. Nelson, Harris Ripps, Malcolm M. Slaughter

Pathology and Laboratory Medicine Faculty Publications

Ionotropic receptors are tightly regulated by second messenger systems and are often present along with their metabotropic counterparts on a neuron's plasma membrane. This leads to the hypothesis that the two receptor subtypes can interact, and indeed this has been observed in excitatory glutamate and inhibitory GABA receptors. In both systems the metabotropic pathway augments the ionotropic receptor response. However, we have found that the metabotropic GABA_B receptor can suppress the ionotropic GABA_A receptor current, in both the in vitro mouse retina and in human amygdala membrane fractions. Expression of amygdala membrane microdomains in Xenopus oocytes by microtransplantation …

Protein Tyrosine Phosphatase-1b Regulates The Tyrosine Phosphorylation Of The Adapter Grb2-Associated Binder 1 (Gab1) In The Retina, Ammaji Rajala, Ashok K. Dilly, Raju Vs Rajala

Wayne State University Associated BioMed Central Scholarship

Abstract

Background

Gab1 (Grb2-associated binder 1) is a key coordinator that belongs to the insulin receptor substrate-1 like family of adaptor molecules and is tyrosine phosphorylated in response to various growth factors, cytokines, and numerous other molecules. Tyrosine phosphorylated Gab1 is able to recruit a number of signaling effectors including PI3K, SHP2 and PLC-γ. In this study, we characterized the localization and regulation of tyrosine phosphorylation of Gab1 in the retina.

Results

Our immuno localization studies suggest that Gab1 is expressed in rod photoreceptor inner segments. We found that hydrogen peroxide activates the tyrosine phosphorylation of Gab1 ex vivo and …

Substance P And The Host Immune Response, Megan Elizabeth Foldenauer

Wayne State University Dissertations

This body of work examined the mechanism by which SP regulates host immunity, specifically, its control of growth factors and TLR expression in the P. aeruginosa-infected cornea. The role of mTOR and VIP in corneal infection and inflammation also was tested.

SP has a dual role in bacterial infection, unexpectedly upregulating growth factor production. This was accompanied by macrophage-specific upregulation of pro-inflammatory cytokines, downregulation of anti-inflammatory cytokines, and upregulation of anti-apoptotic genes, as well as a decrease in arginase-producing macrophages (M2 cells), important in stromal healing in these mice. All of these lead to worsened disease, despite the stimulatory effects …