Search results for "trabecular meshwork"
showing 10 items of 13 documents
Impact of freeze-thaw cytoablation on aqueous outflow patterns in ex vivo anterior chamber perfusion cultures and whole eyes
2022
Background: Porcine eyes have been widely used as ex vivo models in glaucoma research, as they share similar features with human eyes. Freeze-thawing is a non-invasive technique that has been used to obliterate living cells in anterior segment ex vivo cultures, to prepare them for further research such as cellular repopulation. This technique has previously been shown to reduce the intraocular pressure (IOP) in porcine eyes. The aim of this study was to investigate whether freeze-thaw cytoablation causes corresponding canalogram outflow changes in perfused anterior segment cultures (AFT) and whole porcine eyes (WFT). We hypothesized that the known IOP drop in AFT after trabecular meshwork a…
Ventricular tachycardia in non-compaction of left ventricle: Is this a frequent complication?
2007
Background: Isolated left ventricular non-compaction is the result of incomplete myocardial morphogenesis, leading to persistence of the embryonic myocardium. The condition is recognized by an excessively prominent trabecular meshwork and deep intertrabecular recesses of the left ventricle. Whether these intertrabecular recesses are a favorable substrate for ventricular arrhythmias is unclear. Some reports have found that the fatal ventricular arrhythmias may occur in approximately half of the patients. In this report we investigated about this association. Methods and Results: In total we evaluated a continuous series of 238 patients affected by non-compaction. Periodic Holter monitoring w…
Endothelin Antagonism: Effects of FP Receptor Agonists Prostaglandin F2αand Fluprostenol on Trabecular Meshwork Contractility
2006
Purpose This study analyzes additional mechanisms behind the ocular hypotensive effect of prostaglandin F (PGF) receptor (FP receptor) agonists PGF2alpha and fluprostenol (fluprostenol-isopropyl ester [travoprost]), which reduce intraocular pressure (IOP) in patients with glaucoma probably by enhancing uveoscleral flow. The trabecular meshwork (TM) is actively involved in IOP regulation through contractile mechanisms. Contractility of TM is induced by endothelin (ET)-1, a possible pathogenic factor in glaucoma. The involvement of FP receptor agonists in the ET-1 effects on TM function was studied. Methods The effects of FP receptor agonists on contractility of bovine TM (BTM) were investiga…
Endothelin receptor B in trabecular meshwork
2007
Abstract Endothelin-1 (ET-1), the most potent vasoconstrictor known to date, seems to be involved in the pathogenesis of primary open angle glaucoma. ET-1 was found in different tissues of the eye and in high concentrations in the aqueous humour. The effects of ET-1 are mediated by two receptors, ET-A receptor (ET-AR) and ET-B receptor (ET-BR), which are both expressed in bovine trabecular meshwork (TM). ET-1 induced contraction of TM predominantly by activation of ET-AR. This study analyzes the role of ET-BR in TM function and investigates the synthesis of ET-1 by human TM (HTM) cells. The effect of IRL-1620, a specific ET-BR agonist, on contractility of bovine TM (BTM) was investigated wi…
THE NONCOMPACTION OF THE LEFT VENTRICULAR MYOCARDIUM: OUR PEDIATRIC EXPERIENCE
2007
OBJECTIVES: The noncompaction of the left ventricular myocardium is a rare congenital heart disease, characterized by an excessive prominence of trabecular meshwork, spaced out by deep intertrabecular recesses, consequent to the arrest of the normal myocardium embryogenesis. Although there are numerous descriptions, the physiopathological effects of the structural alterations, just like the clinical spectrum and the evolution of the disease, are not totally clarified. In the present study, we have evaluated the natural history of the disease, the familial incidence and the alterations of the systolic and diastolic function. METHODS: We collected a series of 21 young patients who were affect…
Removal of Viscoelastic Substances
2000
All viscoelastics should be completely removed from the eye to reduce the likelihood of increased intraocular pressure. Should OVD retention behind the IOL occur, an unstable refraction could result. Residual high molecular viscous substance is transported away through the trabecular meshwork, with delay, possibly resulting in a protracted postoperative IOP increase. To aspirate viscoelastics various techniques as well as instruments with different aspiration/irrigation adjustments have been proposed, a few of which will be described here. Viscoelastic removal involving the simultaneous irrigation and aspiration through a single cannula (Nevyas, 1987) or two separate cannulas (Brauweiler, 1…
Steady-state levels of retinal 24S-hydroxycholesterol are maintained by glial cells intervention after elevation of intraocular pressure in the rat
2012
Purpose: Our previous studies suggested that CYP46A1 and 24S-hydroxycholesterol. (24SOH) may be associated with glaucoma. Loss of CYP46A1-expressing retinal. ganglion cells is involved in the activation of glia, and therefore possibly in the. disbalance of cholesterol. In this context, the purpose of our present work was to. emphasize the glial and longitudinal CYP46A1 expression after an interventional. glaucoma-related stress triggered by elevated intraocular pressure (IOP). Methods: Sprague–Dawley rats were submitted to laser photocoagulation of the. trabecular meshwork, limbus and episcleral veins in one eye to induce elevated IOP. Rats were euthanized at days 3, 14, 30 and 60 (n = 10 p…
Noncompaction of the Right Ventricle
2010
Noncompaction of the ventricular myocardium is a disease characterized by an increase of the ventricular trabecular meshwork caused by arrest of the normal endomyocardial morphogenesis (Figs. 1, 2, 3). In accordance with the normal human anatomy, the left ventricular wall is well compacted with a few thin trabeculae; on the contrary, the normal right ventricular wall is furrowed by many trabeculae (the trabecula of the marginal septum as well as other ones). For this reason, the term ‘‘noncompaction’’ usually refers to an exclusive or prevalent disease of the left ventricle [1–16]. Recently Song and Aragona et al. [1–3] reported two cases of isolated right-ventricular noncompaction. Accordi…
Clinical guidelines for diagnosing and managing ocular manifestations in children with mucopolysaccharidosis.
2011
The mucopolysaccharidoses (MPS) are a group of rare lysosomal storage disorders characterized by the accumulation of glycosaminoglycans in several tissues and organs. This accumulation results in an array of clinical manifestations and premature death in severe cases. Ocular problems are very common in children with MPS and may involve the cornea, sclera, trabecular meshwork, retina, optic nerve and also the posterior visual pathways. The aims of this study are to give an overview of ocular problems in MPS and to provide clinical guidelines for paediatric ophthalmologists for early diagnosis and management of ocular manifestations in children with MPS. Diagnostic problems may arise in child…
Autoantigens in the trabecular meshwork and glaucoma‐specific alterations in the natural autoantibody repertoire
2019
Abstract Objectives Primary open‐angle glaucoma (POAG) is a neurodegenerative disorder leading to a gradual vision loss caused by progressive damage to the optic nerve. Immunological processes are proposed to be involved in POAG pathogenesis. Altered serological autoantibody levels have been frequently reported, but complete analyses of the natural autoantibodies with respect to disease‐related alterations are scarce. Here, we provide an explorative analysis of pathways and biological processes that may involve naturally immunogenic proteins and highlight POAG‐specific alterations. Methods Mass spectrometry‐based antibody‐mediated identification of autoantigens (MS‐AMIDA) was carried out in…