204 results match your criteria: "F. M. Kirby Center for Molecular Ophthalmology[Affiliation]"

The human amnion has been used for decades in wound healing, particularly burns. Amnion epithelial cells (AECs) have been the focus of extensive research based on their possible pluripotent differentiation ability. A novel, cultured cell population derived from AECs, termed human amnion-derived multipotent progenitor (AMP) cells, secrete numerous cytokines and growth factors that enhance tissue regeneration and reduce inflammation.

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Serum C-reactive protein (CRP), a marker of systemic inflammation, is associated with increased risk for numerous inflammation-driven chronic diseases. A prior longitudinal study showed that the Low Inflammatory Foods Everyday (LIFE) diet, which is rich in dark green leafy vegetables (DGLV), lowered CRP over a mean follow-up period of 6 months. In this retrospective study, we investigate whether patients who consume the LIFE diet or their regular diet plus one component of the LIFE diet (LIFE smoothie), experience reductions in high-sensitivity CRP (hsCRP) in 7 days.

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Glaucoma is a group of progressive optic neuropathies that share common biological and clinical characteristics including irreversible changes to the optic nerve and visual field loss caused by the death of retinal ganglion cells (RGCs). The loss of RGCs manifests as characteristic cupping or optic nerve degeneration, resulting in visual field loss in patients with Glaucoma. Published studies on in vitro RGC differentiation from stem cells utilized classical RGC signaling pathways mimicking retinal development in vivo.

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Compensatory Cross-Modal Plasticity Persists After Sight Restoration.

Front Neurosci

May 2020

Department of Ophthalmology, Center for Advanced Retinal and Ocular Therapeutics, University of Pennsylvania, Philadelphia, PA, United States.

Sensory deprivation prompts extensive structural and functional reorganizations of the cortex resulting in the occupation of space for the lost sense by the intact sensory systems. This process, known as cross-modal plasticity, has been widely studied in individuals with vision or hearing loss. However, little is known on the neuroplastic changes in restoring the deprived sense.

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Ferrous but not ferric iron sulfate kills photoreceptors and induces photoreceptor-dependent RPE autofluorescence.

Redox Biol

July 2020

F.M.Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, 305 Stellar-Chance Laboratory, 422 Curie Blvd, Philadelphia, PA, 19104, USA. Electronic address:

Iron has been implicated in the pathogenesis of retinal degenerative diseases, including ocular siderosis. However, the mechanisms of iron-induced retinal toxicity are incompletely understood. Previous work shows that intravitreal injection of Fe leads to photoreceptor (PR) oxidative stress, resulting in PR death within 14 days, and cones are more susceptible than rods to iron-induced oxidative damage.

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Purpose: To report a case of bull's eye maculopathy, a novel finding in a patient with iron overload secondary to hereditary hemochromatosis with a homozygous mutation of the gene.

Observations: A 39-year-old man with recently diagnosed hereditary hemochromatosis undergoing treatment by serial phlebotomy presented with bilateral progressive blurry vision and recent onset of photopsias and headaches. Fundus examination revealed a symmetric bull's eye maculopathy with photoreceptor loss and retinal pigment epithelium transmission defects in the area of speckled hyper- and hypo-pigmentation by multimodal imaging.

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Mouse hepatitis virus (MHV; murine coronavirus) causes meningoencephalitis, myelitis, and optic neuritis followed by axonal loss and demyelination. This murine virus is used as a common model to study acute and chronic virus-induced demyelination in the central nervous system. Studies with recombinant MHV strains that differ in the gene encoding the spike protein have demonstrated that the spike has a role in MHV pathogenesis and retrograde axonal transport.

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A Mini Review: Moving iPSC-Derived Retinal Subtypes Forward for Clinical Applications for Retinal Degenerative Diseases.

Adv Exp Med Biol

February 2020

F.M. Kirby Center for Molecular Ophthalmology and Center for Advanced Retinal and Ocular Therapeutics (CAROT), Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.

Patient-derived human-induced pluripotent stem cells (iPSCs) have been critical in advancing our understanding of the underlying mechanisms of numerous retinal disorders. Many of these retinal disorders have no effective treatment and result in severe visual impairment and even blindness. Among the retinal degenerative diseases modeled by iPSCs are age-related macular degeneration (AMD), glaucoma, Leber congenital amaurosis (LCA), retinitis pigmentosa (RP), and autosomal dominant retinitis pigmentosa (adRP).

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Chronic inflammation contributes to a number of chronic diseases and can be assessed with C-reactive protein (CRP). In this longitudinal retrospective chart review, we investigate whether patients intensively counseled to eat a specific diet high in dark green leafy vegetables, and thus high beta-carotene, have reductions in plasma high-sensitivity CRP (hsCRP). We term this the Low Inflammatory Foods Everyday (LIFE) diet.

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Purpose: Iron supplementation therapy is used for iron-deficiency anemia but has been associated with macular degeneration in a 43-year-old patient. Iron entry into the neurosensory retina (NSR) can be toxic. It is important to determine conditions under which serum iron might cross the blood retinal barrier (BRB) into the NSR.

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Importance: Next-generation sequencing can detect variants of uncertain significance (VUSs), for some of which gene therapy would not be advantageous. Therefore, the pathogenicity of compound heterozygous or homozygous variants should be confirmed before bilateral vitrectomy and administration of voretigene neparvovec-rzyl.

Objective: To describe an in vitro mutagenesis assay for assessing the pathogenicity of variants in the RPE65 gene.

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Ferroportin-mediated iron export from vascular endothelial cells in retina and brain.

Exp Eye Res

October 2019

F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, 305 Stellar-Chance Laboratory, 422 Curie Blvd, Philadelphia, PA, 19104, USA. Electronic address:

Retinal iron accumulation has been implicated in the pathogenesis of age-related macular degeneration (AMD) and other neurodegenerative diseases. The retina and the brain are protected from the systemic circulation by the blood retinal barrier (BRB) and blood brain barrier (BBB), respectively. Iron levels within the retina and brain need to be tightly regulated to prevent oxidative injury.

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Liver-Specific, but Not Retina-Specific, Hepcidin Knockout Causes Retinal Iron Accumulation and Degeneration.

Am J Pathol

September 2019

F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, 305 Stellar-Chance Laboratory, Philadelphia, Pennsylvania. Electronic address:

The liver secretes hepcidin (Hepc) into the bloodstream to reduce blood iron levels. Hepc accomplishes this by triggering degradation of the only known cellular iron exporter ferroportin in the gut, macrophages, and liver. We previously demonstrated that systemic Hepc knockout (HepcKO) mice, which have high serum iron, develop retinal iron overload and degeneration.

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Increased serum proteins in non-exudative AMD retinas.

Exp Eye Res

September 2019

F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, 305 Stellar-Chance Laboratory, 422 Curie Blvd, Philadelphia, PA, 19104, USA. Electronic address:

The blood retinal barrier (BRB) closely regulates the retinal microenvironment. Its compromise leads to the accumulation of retinal fluid containing potentially harmful plasma components. While eyes with non-exudative age-related macular degeneration (AMD) were previously felt to have an intact BRB, we propose that the BRB in non-exudative AMD eyes may be subclinically compromised, allowing entry of retina-toxic plasma proteins.

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AKT3 Gene Transfer Promotes Anabolic Reprogramming and Photoreceptor Neuroprotection in a Pre-clinical Model of Retinitis Pigmentosa.

Mol Ther

July 2019

Center for Advanced Retinal and Ocular Therapeutics, F.M. Kirby Center for Molecular Ophthalmology, Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA. Electronic address:

Mutations within over 250 known genes are associated with inherited retinal degeneration. Clinical success following gene-replacement therapy for congenital blindness due to RPE65 mutations establishes a platform for the development of downstream treatments targeting other forms of inherited ocular disease. Unfortunately, several challenges relevant to complex disease pathology and limitations of current gene-transfer technologies impede the development of related strategies for each specific form of inherited retinal degeneration.

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Comparative AAV-eGFP Transgene Expression Using Vector Serotypes 1-9, 7m8, and 8b in Human Pluripotent Stem Cells, RPEs, and Human and Rat Cortical Neurons.

Stem Cells Int

January 2019

F.M. Kirby Center for Molecular Ophthalmology and Center for Advanced Retinal and Ocular Therapeutics (CAROT), Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Pennsylvania, PA 19104, USA.

Recombinant adeno-associated virus (rAAV), produced from a nonpathogenic parvovirus, has become an increasing popular vector for gene therapy applications in human clinical trials. However, transduction and transgene expression of rAAVs can differ across and ex vivo cellular transduction strategies. This study compared 11 rAAV serotypes, carrying one reporter transgene cassette containing a cytomegalovirus immediate-early enhancer (eCMV) and chicken beta actin (CBA) promoter driving the expression of an enhanced green-fluorescent protein (eGFP) gene, which was transduced into four different cell types: human iPSC, iPSC-derived RPE, iPSC-derived cortical, and dissociated embryonic day 18 rat cortical neurons.

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Purpose: Mutations in the megalin-encoding gene, LRP2, cause high myopia as seen in patients suffering from Donnai-Barrow/facio-oculo-acoustico-renal syndrome. Megalin is present in both the nonpigmented epithelium of the ciliary body and in the RPE. In this study, we set out to establish an animal model to study the mechanisms underlying the ocular phenotype and to establish if high myopia/megaophthalmos is induced by postnatal megalin-deficiency in the RPE.

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Comparative localization of cystathionine beta synthases and cystathionine gamma lyase in canine, non-human primate and human retina.

Exp Eye Res

April 2019

Department of Clinical Sciences and Advanced Medicine, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA. Electronic address:

Chronic exposure of the retina to light and high concentrations of polyunsaturated fatty acid in photoreceptor cells make this tissue susceptible to oxidative damage. As retinal degenerative diseases are associated with photoreceptor degeneration, the antioxidant activity of both hydrogen sulfide (HS) and glutathione (GSH) may play an important role in ameliorating disease progression. HS production is driven by cystathionine-γ-lyase (CSE) and cystathionine-β-synthase (CBS), the key enzymes that also drive transsulfuration pathway (TSP) necessary for GSH production.

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Potential Treatment of Retinal Diseases with Iron Chelators.

Pharmaceuticals (Basel)

October 2018

F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, Perelman School of Medicine at the University of Pennsylvania, 305 Stellar-Chance Laboratory, Philadelphia, PA 19104, USA.

Iron is essential for life, while excess iron can be toxic. Iron generates hydroxyl radical, which is the most reactive free radical, causing oxidative stress. Since iron is absorbed through the diet but not excreted from the body, it accumulates with age in tissues, including the retina, consequently leading to age-related toxicity.

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Purpose: To describe patterns of hypoautofluorescence in eyes with neovascular age-related macular degeneration occurring after subretinal hemorrhage.

Methods: This was a retrospective descriptive analysis of neovascular age-related macular degeneration eyes presenting with subretinal hemorrhage over the last 5 years that underwent serial multimodal imaging. A review of color fundus photographs, fundus autofluorescence, near-infrared reflectance, and optical coherence tomography was performed at baseline and all available follow-up visits to document the course and evolution of subretinal hemorrhage in these eyes.

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Apolipoprotein E (APOE) is a component of lipid-transporting particles and a recognition ligand for receptors, which bind these particles. The APOE isoform ε2 is a risk factor for age-related macular degeneration; nevertheless, APOE absence in humans and mice does not significantly affect the retina. We found that retinal cholesterol biosynthesis and the levels of retinal cholesterol were increased in mice, whereas cholesterol elimination by metabolism was decreased.

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Identification of a novel pathogenic missense mutation in using whole exome sequencing: a case report.

Br J Ophthalmol

June 2019

Center for Advanced Retinal and Ocular Therapeutics (CAROT) and F.M. Kirby Center for Molecular Ophthalmology, Scheie Eye Institute, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania, USA

Background: Variants in , which encodes pre-mRNA processing factor 31 homolog, are known to cause autosomal-dominant retinitis pigmentosa (adRP) with incomplete penetrance. However, the majority of mutations cause null alleles, with only two proven pathogenic missense mutations. We identified a novel missense mutation in in a family with adRP.

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Comparing Clinical Perimetry and Population Receptive Field Measures in Patients with Choroideremia.

Invest Ophthalmol Vis Sci

July 2018

Center for Advanced Retinal and Ocular Therapeutics (CAROT), University of Pennsylvania, Philadelphia, Pennsylvania, United States.

Purpose: Choroideremia (CHM) is an X-linked recessive form of hereditary retinal degeneration, which, at advanced stages, leaves only small central islands of preserved retinal tissue. Unlike many other retinal diseases, the spared tissue in CHM supports excellent central vision and stable fixation. Such spared topography in CHM presents an ideal platform to explore the relationship between preserved central retinal structure and the retinotopic organization of visual cortex by using functional magnetic resonance imaging (fMRI).

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RGC Neuroprotection Following Optic Nerve Trauma Mediated By Intranasal Delivery of Amnion Cell Secretome.

Invest Ophthalmol Vis Sci

May 2018

Scheie Eye Institute and F.M. Kirby Center for Molecular Ophthalmology, University of Pennsylvania, Philadelphia, Pennsylvania, United States.

Purpose: Intranasally delivered ST266, the biological, proteinaceous secretome of amnion-derived multipotent progenitor cells, reduces retinal ganglion cell (RGC) loss, optic nerve inflammation, and demyelination in experimental optic neuritis. This unique therapy and novel administration route delivers numerous cytokines and growth factors to the eye and optic nerve, suggesting a potential to also treat other optic neuropathies. Thus, ST266-mediated neuroprotection was examined following traumatic optic nerve injury.

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