Search results for "Retinal"
showing 10 items of 631 documents
Ultraviolet vision in lacertid lizards: evidence from retinal structure, eye transmittance, SWS1 visual pigment genes, and behaviour
2014
Abstract Ultraviolet (UV) vision and UV colour patches have been reported in a wide range of taxa and are increasingly appreciated as an integral part of vertebrate visual perception and communication systems. Previous studies with Lacertidae, a lizard family with diverse and complex coloration, have revealed the existence of UV-reflecting patches that may function as social signals. However, confirmation of the signalling role of UV coloration requires demonstrating that the lizards are capable of vision in the UV waveband. Here we use a multidisciplinary approach to characterize the visual sensitivity of a diverse sample of lacertid species. Spectral transmission measurements of the ocula…
Erythrocyte Phospholipid and Polyunsaturated Fatty Acid Composition in Diabetic Retinopathy
2014
Background: Long chain polyunsaturated fatty acids (LCPUFAs) including docosahexaenoic acid and arachidonic acid are suspected to play a key role in the pathogenesis of diabetes. LCPUFAs are known to be preferentially concentrated in specific phospholipids termed as plasmalogens. This study was aimed to highlight potential changes in the metabolism of phospholipids, and particularly plasmalogens, and LCPUFAs at various stages of diabetic retinopathy in humans. Methodology and Principal Findings: We performed lipidomic analyses on red blood cell membranes from controls and mainly type 2 diabetes mellitus patients with or without retinopathy. The fatty acid composition of erythrocytes was det…
Metabolic syndrome triggered by high-fructose diet favors choroidal neovascularization and impairs retinal light sensitivity in the rat
2014
Diabetic retinopathy and age-related macular degeneration are the leading causes of blindness in Western populations. Although it is a matter of controversy, large-scale population-based studies have reported increased prevalence of age-related macular degeneration in patients with diabetes or diabetic retinopathy. We hypothesized that metabolic syndrome, one of the major risk factors for type 2 diabetes, would represent a favorable environment for the development of choroidal neovascularization, the main complication of age-related macular degeneration. The fructose-fed rat was used as a model for metabolic syndrome in which choroidal neovascularization was induced by laser photocoagulatio…
Pars Plana Vitrectomy for Visually Disturbing Vitreous Floaters in Pseudophacic Eyes
2011
Background The aim of this study was to evaluate the role of vitrectomy in patients with visually disturbing vitreous opacities. Patients and methods A retrospective analysis of the patient characteristics and the outcome of all pseudophacic eyes, which consecutively received in the decade 1996 to 2005 20 G pars plana vitrectomy for visually disturbing floaters, was carried out at the Mainz University Eye Clinic. Results Forty-one eyes of 32 patients (63 % university graduates, median age: 64 years) were included in the study. The mean axial length of the globe was 25.3 mm (range: 22.8 to 28.9 mm). Additional pathologies having influence on the vitreous condition were history of laser or cr…
Lipid composition of the human eye: are red blood cells a good mirror of retinal and optic nerve fatty acids?
2011
International audience; BACKGROUND: The assessment of blood lipids is very frequent in clinical research as it is assumed to reflect the lipid composition of peripheral tissues. Even well accepted such relationships have never been clearly established. This is particularly true in ophthalmology where the use of blood lipids has become very common following recent data linking lipid intake to ocular health and disease. In the present study, we wanted to determine in humans whether a lipidomic approach based on red blood cells could reveal associations between circulating and tissue lipid profiles. To check if the analytical sensitivity may be of importance in such analyses, we have used a do…
Upregulation of antibody response to heat shock proteins and tissue antigens in an ocular ischemia model.
2011
PURPOSE. The aim of this study was to characterize the serum antibody reactivities occurring after ocular ischemia reperfusion. The time course of serum antibody responses was examined. METHODS. Wistar rats were exposed to transient ocular ischemia by elevating intraocular pressure to 130 mm Hg for 60 minutes. Axonal damage was evaluated on optic-nerve sections 2 and 4 weeks later. Blood samples collected before and several times after ischemia were used for antibody detection via customized protein microarrays. Different tissue antigens, including heat shock proteins (HSPs) and crystallins, were selected based on previous identification of antibody reactivities in studies on ischemic event…
Color Doppler Hemodynamics of Giant Cell Arteritis
1994
Objectives: To determine quantitative and qualitative hemodynamic alterations within the ophthalmic, central retinal, and short posterior ciliary arteries in patients with giant cell arteritis (GCA) proved by biopsy specimen. Design, Patients, and Setting: A consecutive case series of patients with GCA referred to an urban eye hospital who were evaluated with color Doppler imaging that was used to analyze orbital blood flow velocities and vascular resistance in 22 consecutive patients with GCA compared with age and sex-matched controls. Results: Patients with GCA all demonstrated significantly reduced central retinal and short posterior ciliary arterial mean flow velocities as well as signi…
Ocular Phenotype of Relaxin Gene Knockout (Rln-/-) Mice
2020
Purpose: To test if relaxin deficiency affects ocular structure and function we investigated expression of relaxin (Rln) and RXFP receptors (Rxfp1, Rxfp2), and compared ocular phenotypes in relaxin gene knockout (Rln-/- ) and wild type (Rln+/+ ) mice. Materials and Methods: Rln, Rxfp1 and Rxfp2 mRNA expression was detected in ocular tissues of Rln+/+ mice using RT-PCR. The eyes of 11 Rln-/- and 5 Rln+/+ male mice were investigated. Corneal and retinal thickness was assessed using optical coherence tomography. Intraocular pressure was measured using a rebound tonometer. Retinal, choroidal and sclera morphology and thickness were evaluated histologically. Eyes were collected and fixed for imm…
Ultrastructural studies of the retina in infantile neuronal ceroid-lipofuscinosis.
1988
A 9-year-old boy who had died of infantile neuronal ceroid-lipofuscinosis had experienced retina-derived visual failure. Ophthalmologically and morphologically, his retina was severely atrophic and scarred by a dense fibrillary gliosis while photoreceptor cells had completely disappeared, cells of the bipolar layer had decreased in number and had become atrophic beyond cytologic recognition. Retinal pigment epithelial cells had undergone either atrophy or proliferation. Disease-specific granular lipopigments had accumulated in perikarya and processes of remaining cells and were infrequently associated with melanin within huge melanolipofuscin bodies and RPE cells of sessile and migrating na…
Branch Retinal Vein Occlusion Followed by Central Retinal Artery Occlusion in Churg-Strauss Syndrome: Unusual Ocular Manifestations in Allergic Granu…
2009
Purpose To describe a rare branch retinal vein occlusion (BRVO) followed by central retinal artery occlusion (CRAO) in a patient with Churg-Strauss syndrome (CSS). Methods A 55-year-old man with a not yet diagnosed CSS developed a BRVO in the left eye and 1 year later a CRAO with painless and acute vision loss in the same eye. Medical history included bronchial asthma, history of allergy, eosinophilic pneumonia, bilateral pleuric and pericardial effusion, hypereosinophilia, and purpuric vasculitis. Results CRAO in the left eye was diagnosed by retinal whitening and a cherry red spot with coexisting old BRVO evidenced by previous laser photocoagulation. Corticosteroids and cyclophosphamide t…