Search results for "Retina"
showing 10 items of 864 documents
Alterations in the spontaneous activity of cells in the guinea pig pineal gland and visual system produced by pineal indoles
1982
The indoles serotonin (SER), melatonin (MEL), 5-methoxytryptophol (5-MTL) and 5-hydroxytryptophol (5-HTL) were administered during daytime microelectrophoretically to 240 cells in the pineal gland of the guniea-pig. The action of SER and 5-HTL was predominantly depressant on the electrical activity, MEL and 5-MTL caused an excitation in most of the units. Although MEL and 5-MTL caused fairly similar reactions on average, they appear to act on different cells. The effects of microelectrophoretically applied MEL and 5-MTL on the spontaneous or evoked activity in the visual system (retinal ganglion cells, optic tract, lateral lateral geniculate body, superior colliculus) of the guinea-pig were…
Thyroid hormone deficiency disrupts rat eye neurodevelopment
2010
Clinical and experimental studies have highlighted the role played by thyroid hormones (TH) in neural and neuro-sensorial development. However, knowledge on TH mechanisms on the developing visual system is still incomplete. To uncover TH actions on the eyes and vision we carried out a microscopical study on the role of TH in the developing retina and optic nerve, in a rat model of controlled TH deficiency (THD). Morphometric and stereological analyses of the retina and optic nerve showed a reduction in the volume of the eye (p<0.001) and optic nerve cross-sectional area (p<0.001), and thinning of the retinal layers (p<0.001). Glial development and myelination was significantly delayed in th…
Mouse photoreceptor synaptic ribbons lose and regain material in response to illumination changes
2004
Abstract Chemical synapses equipped with ribbons are tonically active, high-output synapses. The ribbons may play a role in the trafficking of synaptic vesicles. Recent findings in retinal rod cells of BALB/c mice indicate that ribbons are large and smooth in the dark phase, and, due to the formation and release of protrusions, small during the light phase. As a consequence of these changes, ribbons may traffick fewer vesicles in the light than in the dark phases. The aim of the present study was to find out whether the above ribbon changes in this mouse strain are strictly illumination-dependent and which signalling processes may be involved. Here, we show that ribbons form protrusions and…
Heavy versus standard silicone oil in the management of retinal detachment with macular hole in myopic eyes
2011
PURPOSE: The purpose of this study was to compare pars plana vitrectomy (PPV) with 1000 cSt silicone oil endotamponade and PPV with densiron endotamponade for retinal detachment with macular hole and posterior staphyloma in highly myopic eyes. PATIENTS AND METHODS: In a prospective study, 30 eyes of 30 patients were randomly assigned to PPV and densiron (n = 15) or PPV with silicone oil (n = 15). All eyes had laser photocoagulation of the macular hole rim after PPV. Silicone oil or densiron was removed 12 weeks after surgery. Patients were followed-up for 6 months after oil removal. RESULTS: In the densiron group, the retinal reattachment rate was 100% with densiron in situ and 87% after it…
A mouse model of in vivo chemical inhibition of retinal calcium-independent phospholipase A2 (iPLA2).
2013
International audience; Numerous studies have reported the implication of calcium-independent phospholipase A2 (iPLA2) in various biological mechanisms. Most of these works have used in vitro models and only a few have been carried out in vivo on iPLA2(-/-) mice. The functions of iPLA2 have been investigated in vivo in the heart, brain, pancreatic islets, and liver, but not in the retina despite its very high content in phospholipids. Phospholipids in the retina are known to be involved in several various key mechanisms such as visual transduction, inflammation or apoptosis. In order to investigate the implication of iPLA2 in these processes, this work was aimed to build an in vivo model of…
Transcriptional analysis of rat photoreceptor cells reveals daily regulation of genes important for visual signaling and light damage susceptibility.
2013
Photoreceptor cells face the challenge of adjusting their function and, possibly, their susceptibility to light damage to the marked daily changes in ambient light intensity. To achieve a better understanding of photoreceptor adaptation at the transcriptional level, this study aimed to identify genes which are under daily regulation in photoreceptor cells using microarray analysis and quantitative PCR. Included in the gene set obtained were a number of genes which up until now have not been shown to be expressed in photoreceptor cells, such as Atf3 (activating transcription factor 3) and Pde8a (phosphodiesterase 8A), and others with a known impact on phototransduction and/or photoreceptor s…
Assessment of intravitreal anti-VEGF drugs and dexamethasone for retinal diseases in real world setting: A multi-centre prospective study from Southe…
2022
Describe drug utilisation and clinical outcomes of intravitreal anti-VEGF drug and dexamethasone use in the real-world setting in Southern Italy using data from multi-centre study of retinal disease. Clinical data of retinal disease patients treated with anti-VEGF drugs and dexamethasone implant in 6 out-patient ophthalmology centres from Southern Italy were collected by means of an electronic case report form. Patients receiving at least one intravitreal injection/implant of the study drugs were followed for up to two years and described in terms of demographics and clinical characteristics. Drug utilisation patterns were described. A sign-rank test was used to compare clinical data on vi…
Outcomes of treatment of pediatric choroidal neovascularization with intravitreal antiangiogenic agents: the results of the KKESH International Colla…
2014
Purpose: To evaluate safety and clinical results of intravitreal antiangiogenic agents for choroidal neovascularization in pediatric patients. Methods: Retrospective, multicenter, interventional case series. A total of 45 eyes of 39 pediatric patients with choroidal neovascularization of various etiologies were treated with intravitreal injection of antiangiogenic agents (1.25 mg per 0.05 mL of bevacizumab or 0.5 mg per 0.05 mL of ranibizumab). Results: There were 24 girls and 15 boys with group median age of 13 years (range, 3–17 years). Mean follow-up period was 12.8 months (range, 3–60 months). Median visual acuity in terms of logarithm of the minimum angle of resolution at presentation …
Best-corrected visual acuity and retinal thickness are associated with improved cortical visual processing in treated wet AMD patients
2015
Purpose In response to anti-VEGF treatment for wet AMD retinal anatomy and visual acuity is often remedied. In our previous study, we showed that visual evoked potentials (VEP) improve following successful anti-VEGF treatment. The aim of this study was to investigate, how visual acuity and retinal thickness changes are reflected in VEP parameters. Moreover, we wanted to assess the feasibility of VEP as a novel monitoring tool for wet AMD patients. Methods A total of 16 patients and six control subjects were enrolled in this study. Patients received three bevacizumab intravitreal injections. At the beginning of the study and four to 6 weeks after the last injection, the best-corrected visual…
Intravitreal bevacizumab plus grid laser photocoagulation or intravitreal bevacizumab or grid laser photocoagulation for diffuse diabetic macular ede…
2013
To evaluate the anatomical and functional outcomes at 24 months in patients with diffuse diabetic macular edema treated with primary intravitreal bevacizumab (IVB) plus grid laser photocoagulation (GLP) or primary IVB alone or GLP alone.Retrospective, interventional, comparative, multicenter study. We included in this analysis 141 eyes of 120 patients with diffuse diabetic macular edema treated with primary IVB alone (Group A), 120 eyes of 94 patients with GLP therapy (Group B), and 157 eyes of 104 patients treated with IVB plus GLP (Group C).In all 3 groups, the authors observed improvement of Early Treatment Diabetic Retinopathy Study best-corrected visual acuity from baseline to 24-month…