Search results for "ocular"
showing 10 items of 1219 documents
Protective activation of the endocannabinoid system during ischemia in dopamine neurons
2006
Endocannabinoids act as neuroprotective molecules promptly released in response to pathological stimuli. Hence, they may represent one component of protection and/or repair mechanisms mobilized by dopamine (DA) neurons under ischemia. Here, we show that the endocannabinoid 2-arachidonoyl-glycerol (2-AG) plays a key role in protecting DA neurons from ischemia-induced altered spontaneous activity both in vitro and in vivo. Accordingly, neuroprotection can be elicited through moderate cannabinoid receptor type-1 (CB1) activation. Conversely, blockade of endocannabinoid actions through CB1 receptor antagonism worsens the outcome of transient ischemia on DA neuronal activity. These findings indi…
A restricted population of CB1 cannabinoid receptors with neuroprotective activity.
2014
The CB1 cannabinoid receptor, the main molecular target of endocannabinoids and cannabis active components, is the most abundant G protein-coupled receptor in the mammalian brain. Of note, CB1 receptors are expressed at the synapses of two opposing (i.e., GABAergic/inhibitory and glutamatergic/excitatory) neuronal populations, so the activation of one and/or another receptor population may conceivably evoke different effects. Despite the widely reported neuroprotective activity of the CB1 receptor in animal models, the precise pathophysiological relevance of those two CB1 receptor pools in neurodegenerative processes is unknown. Here, we first induced excitotoxic damage in the mouse brain b…
Effects of Fenoldopam on Intracranial Pressure and Hemodynamic Variables at Normal and Elevated Intracranial Pressure in Anesthetized Pigs
1994
Fenoldopam (FE), a dopamine DA1-receptor agonist, has been introduced for treatment of arterial hypertension and heart failure and for preservation of renal function. Vasodilators are generally assumed to affect all vascular beds including the cerebral circulation. We have evaluated effects of FE-induced (4 micrograms.kg-1.min-1) arterial hypotension on intracranial pressure (ICP) and intraocular pressure (IOP) under conditions of normal and increased intracranial elastance. ICP and IOP responses to hypertension were tested by infusion of angiotensin II (15 micrograms.kg-1.min-1), and the response to hypercapnia was tested by elimination and reintegration of soda lime canisters in the breat…
An anti-interleukin-2 receptor drug attenuates T- helper 1 lymphocytes-mediated inflammation in an acute model of endotoxin-induced uveitis.
2014
The aim of the present study was to evaluate the anti-inflammatory efficacy of Daclizumab, an anti-interleukin-2 receptor drug, in an experimental uveitis model upon a subcutaneous injection of lipopolysaccharide into Lewis rats, a valuable model for ocular acute inflammatory processes. The integrity of the blood-aqueous barrier was assessed 24 h after endotoxin-induced uveitis by evaluating two parameters: cell count and protein concentration in aqueous humors. The histopathology of all the ocular structures (cornea, lens, sclera, choroid, retina, uvea, and anterior and posterior chambers) was also considered. Enzyme-linked immunosorbent assays of the aqueous humor samples were performed t…
Chemoimmunotherapy with methotrexate, cytarabine, thiotepa, and rituximab (MATRix regimen) in patients with primary CNS lymphoma: results of the firs…
2016
BACKGROUND: Standard treatment for patients with primary CNS lymphoma remains to be defined. Active therapies are often associated with increased risk of haematological or neurological toxicity. In this trial, we addressed the tolerability and efficacy of adding rituximab with or without thiotepa to methotrexate-cytarabine combination therapy (the MATRix regimen), followed by a second randomisation comparing consolidation with whole-brain radiotherapy or autologous stem cell transplantation in patients with primary CNS lymphoma. We report the results of the first randomisation in this Article.METHODS: For the international randomised phase 2 International Extranodal Lymphoma Study Group-32 …
Influence of trifocal intraocular lenses on standard autorefraction and aberrometer-based autorefraction.
2019
To study the agreement between manifest refraction and objective refraction measured with two autorefractor models and an aberrometer in eyes implanted with a trifocal diffractive intraocular lens (IOL).IOA Madrid Innova Ocular, Madrid, Spain.Prospective comparative cohort study.An autorefractor keratometer (KR-8800), based on a Scheiner double pinhole, and a 3-dimension wavefront topography aberrometer system (OPD-Scan III), based on the scanning-slit retinoscopy principle, were used to obtain objective refraction readings. In addition, lower-order Zernike coefficients (Z) were used to calculate objective refraction. A set of 7 different results was obtained in power vector notation (spher…
Effects of cromakalim on acetylcholine release and smooth muscle contraction in guinea-pig small intestine
1989
The effects of the potassium channel opener cromakalim on smooth muscle contraction and 3H-acetyl-choline release were studied simultaneously in guinea-pig longitudinal muscle myenteric plexus preparations which had been preincubated with 3H-choline. Cromakalim (10 mumol/l) inhibited more markedly the smooth muscle contractions caused by the release of endogenous acetylcholine (via electrical stimulation or via activation of nicotine- and 5-HT3-receptors) than contractions induced by pilocarpine. Cromakalim (10 mumol/l) did not affect the release of 3H-acetylcholine evoked by electrical stimulation or by stimulation of nicotine- and 5-HT3-receptors. In contrast, the release of 3H-acetylchol…
Deep Learning Estimation of 10-2 and 24-2 Visual Field Metrics Based on Thickness Maps from Macula OCT.
2021
Purpose To develop deep learning (DL) systems estimating visual function from macula-centered spectral-domain (SD) OCT images. Design Evaluation of a diagnostic technology. Participants A total of 2408 10-2 visual field (VF) SD OCT pairs and 2999 24-2 VF SD OCT pairs collected from 645 healthy and glaucoma subjects (1222 eyes). Methods Deep learning models were trained on thickness maps from Spectralis macula SD OCT to estimate 10-2 and 24-2 VF mean deviation (MD) and pattern standard deviation (PSD). Individual and combined DL models were trained using thickness data from 6 layers (retinal nerve fiber layer [RNFL], ganglion cell layer [GCL], inner plexiform layer [IPL], ganglion cell-IPL […
Effectiveness of anti-vascular endothelial growth factors in neovascular age-related macular degeneration and variables associated with visual acuity…
2021
Objective To assess the overall effectiveness of anti-vascular endothelial growth factor (VEGF) therapy in treatment-naïve patients with neovascular age-related macular degeneration (nAMD) in a clinical practice setting. Study design EAGLE was a retrospective, 2-year, cohort observational, multicenter study conducted in Italy that analyzed secondary data of treatment-naïve patients with nAMD. The primary endpoint evaluated the mean annualized number of anti-VEGF injections at Years 1 and 2. The main secondary endpoints analyzed the mean change in visual acuity (VA) from baseline and variables associated with visual outcomes at Years 1 and 2. Results Of the 752 patients enrolled, 745 (99.07…
Visual letter similarity effects during sentence reading: Evidence from the boundary technique
2018
The study of how the cognitive system encodes letter identities from the visual input has received much attention in models of visual word recognition but it has typically been overlooked in models of eye movement control in reading. Here we examined how visual letter similarity affects early word processing during reading using Rayner's (1975) boundary change technique in which the parafoveal preview of the target word was either identical (e.g., frito-frito [fried]) or a one-letter-different nonword (e.g., frjto-frito vs. frgto-frito). Critically, the substituted letter in the nonword was visually similar (based on letter confusability norms) or visually dissimilar. Results showed shorter…