Search results for "Retinal Pigment Epithelium"
showing 10 items of 62 documents
Binding of 11-cis retinaldehyde to the partially purified cellular retinaldehyde binding protein from bovine retinal pigment epithelium.
1987
11-cis retinaldehyde binding analysis was performed on a bovine retinal pigment epithelium preparation of cellular retinaldehyde binding protein (CRALBP), whose purity degree was estimated as 75%. Equilibrium binding studies were carried out measuring the replacement of tritium-labeled with unlabeled 11-cis retinaldehyde at 25 degrees C. Analysis of the experimental data both by a direct curve-fitting procedure utilizing a non linear least square regression analysis and by a conventional Scatchard plot revealed a single non-interacting binding site with an apparent equilibrium constant of 0.9 X 10(-7) M. A binding stoichiometry of approximately 1 mol of 11-cis retinaldehyde/mol of binding p…
Novel inulin-based mucoadhesive micelles loaded with corticosteroids as potential transcorneal permeation enhancers
2017
In this work a new copolymer of inulin (INU) derivatized with ethylendiamine (EDA) and retinoic acid (RA), named INU-EDA-RA, was synthetized, characterized and employed to produce micelles as carriers for topical administration of corticosteroids for the potential treatment of diseases of posterior eye segment. Spectroscopic analysis confirmed a molar derivatization degree of 11.30 and 4.30% in EDA and RA, respectively. INU-EDA-RA micelles are capable of strong mucoadhesive interactions which result time-independent and stable over time but concentration depending. Moreover micelles are able to encapsulate efficiently from 3 to 13% (w/w) of lipophilic drugs, as dexamethasone, triamcinolone …
Clinical spectrum of eye malformations in four patients with Mowat-Wilson syndrome
2015
Mowat-Wilson syndrome (MWS) is a rare genetic syndrome characterized by a specific facial gestalt, intellectual deficiency, Hirschsprung disease and multiple congenital anomalies. Heterozygous mutations or deletions in the zinc finger E-box-binding homeobox2 gene (ZEB2) cause MWS. ZEB2 encodes for Smad-interacting protein 1, a transcriptional co-repressor involved in TGF-beta and BMP pathways and is strongly expressed in early stages of development in mice. Eye abnormalities have rarely been described in patients with this syndrome. Herein, we describe four patients (two males and two females; mean age 7 years) with MWS and eye malformations. Ocular anomalies included, iris/retinal coloboma…
Patterns of cytokeratin and vimentin expression in the human eye
1988
We studied the expression of the various cytokeratin (CK) polypeptides and vimentin in tissues of the human eye by applying immunocytochemical procedures using a panel of monoclonal antibodies as well as by performing biochemical analyses of microdissected tissues. Adult corneal epithelium was found to contain significant amounts of the cornea-specific CKs nos. 3 and 12 as well as CK no. 5, and several additional minor CK components. Among these last CKs, no. 19 was found to exhibit an irregular mosaic-like staining pattern in the peripheral zone of the corneal epithelium, while having a predominantly basal distribution in the limbal epithelium. Both the fetal corneal epithelium and the con…
Decreasing dietary linoleic acid promotes long chain omega-3 fatty acid incorporation into rat retina and modifies gene expression
2011
International audience; Age-related macular degeneration (AMD) may be partially prevented by dietary habits privileging the consumption of ω3 long chain polyunsaturated fatty acids (ω3s) while lowering linoleic acid (LA) intake. The present study aimed to document whether following these epidemiological guidelines would enrich the neurosensory retina and RPE with ω3s and modulate gene expression in the neurosensory retina. Rat progenitors and pups were fed with diets containing low or high LA, and low or high ω3s. After scotopic single flash and 8-Hz-Flicker electroretinography, rat pups were euthanized at adulthood. The fatty acid profile of the neurosensory retina, RPE, liver, adipose tis…
Ethanol-Induced Oxidative Stress Modifies Inflammation and Angiogenesis Biomarkers in Retinal Pigment Epithelial Cells (ARPE-19): Role of CYP2E1 and …
2020
The retinal pigment epithelium (RPE) plays a key role in retinal health, being essential for the protection against reactive oxygen species (ROS). Nevertheless, excessive oxidative stress can induce RPE dysfunction, promoting visual loss. Our aim is to clarify the possible implication of CYP2E1 in ethanol (EtOH)-induced oxidative stress in RPE alterations. Despite the increase in the levels of ROS, measured by fluorescence probes, the RPE cells exposed to the lowest EtOH concentrations were able to maintain cell survival, measured by the Cell Proliferation Kit II (XTT). However, EtOH-induced oxidative stress modified inflammation and angiogenesis biomarkers, analyzed by proteome array, ELIS…
Laserfotokoagulation und photodynamische Therapie (PDT) zur Behandlung der retinalen angiomatösen Proliferation (RAP) bei feuchter altersabhängiger M…
2008
BACKGROUND: Retinal angiomatous proliferation (RAP) is a subtype of neovascular age-related macular degeneration (AMD) with particularly bad prognosis. Diverse treatment modalities are performed. PATIENTS AND METHODS: This is a retrospective review on the treatment results of 41 consecutive patients from 1 / 2003 to 12 / 2005 with RAP stage 1 - 3 (Yannuzzi classification), who were treated with laser photocoagulation, photodynamic therapy (PDT) and intravitreal injection of triamcinolone acetonide (IVT). Follow-up was 12 months minimally. RESULTS: In RAP stage I complete closure of the vascular lesion in 14 / 22 eyes was achieved by 1.2 ± 0.5 sessions of laser photocoagulation (4 × combined…
Inflammatory cytokines decrease viability and alter ganglioside profile in retinal pigment epithelium cells
2013
Purpose Early stages of Age related Macular Degeneration (AMD) are characterized by dysfunction and degeneration of the retinal pigment epithelium (RPE) cells, which participate in the death of the overlying photoreceptors ultimately leading to loss of vision. Gangliosides (GG) make a wide and heterogeneous family of sialic-acid-containing glycosphingolipids, composed of a sugar chain branched on a ceramide. They are major components of cellular membranes, particularly abundant in the brain and nervous tissue, including retina. While their developmental and neuroprotective actions have been demonstrated, their precise role in retina’s function and its pathologies is still poorly understood.…
Bilateral maculopathy after exposure to a laser pointer: Optical coherence tomography angiography findings.
2018
Abstract Case report A 36-year-old man went to the emergency department the day after exposure to a laser pointer. Funduscopy revealed dispersed macular pigment alterations, and optical coherence tomography showed a disruption of the retinal layers. The visual acuity was counting fingers in both eyes. Nine months later, optical coherence tomography angiography showed a rarefaction in the choriocapillaris vascular flow in the area of the laser injuries. Discussion The retinal layer mainly damaged by the laser injury was the retinal pigment epithelium. However, it is suggested that the laser injury could involve tissues beyond the retinal pigment epithelium, since a rarefaction of the chorioc…
Assessment of the toxicity of cholesterol oxides on retinal pigment epithelial cultured cells
2006
International audience; Purpose: Among the retinal lipid deposits found in AMD (age related macular degeneration), esterified and unesterified cholesterol have been identified. Cholesterol that accumulates in Bruch's membrane could be oxidized and lead to cholesterol oxides known as oxysterols. These compounds have cytotoxic activities on many vascular cell types, and we conducted this study to evaluate the cytotoxics effects of oxysterols on retinal pigment epithelial (RPE) cells. Methods: Human RPE cells (ARPE–19) were cultured and treated by 7–ketocholesterol (7–keto), 7–betahydroxycholesterol (7–beta) and 25–hydroxycholesterol (25–OH). ARPE–19 cells viability was determined with MTT ana…