Investigative ophthalmology & visual science
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Invest. Ophthalmol. Vis. Sci. · Sep 2007
Randomized Controlled Trial Comparative StudyEffects of topical clonidine versus brimonidine on choroidal blood flow and intraocular pressure during squatting.
Clonidine and brimonidine, two alpha-2 agonists, have been shown to reduce intraocular pressure (IOP) in patients with glaucoma. Little is known, however, about the exact role of alpha receptors in the control of ocular blood flow in the posterior pole of the eye. Hence, the study was conducted to investigate the effects of topical clonidine versus topical brimonidine on choroidal blood flow and intraocular pressure during squatting. ⋯ Topical alpha-2 agonists may induce changes in choroidal blood flow, even after a single administration. Long-term studies are needed to study potential effects of brimonidine and clonidine in the clinical setting.
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Invest. Ophthalmol. Vis. Sci. · Sep 2007
Impulse activity in corneal sensory nerve fibers after photorefractive keratectomy.
To evaluate the changes in spontaneous and stimulus-evoked nerve impulse activity of corneal polymodal and mechanonociceptor sensory fibers of the cornea after photorefractive keratectomy (PRK). ⋯ The spontaneous impulse activity and the abnormal responsiveness shown by a part of the corneal nerve fibers innervating the injured cornea are presumably the neurophysiological substrate of the pain sensations experienced by human patients hours after PRK surgery.
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Invest. Ophthalmol. Vis. Sci. · Sep 2007
Suppression of diabetes-induced retinal inflammation by blocking the angiotensin II type 1 receptor or its downstream nuclear factor-kappaB pathway.
To investigate the involvement of the renin-angiotensin system (RAS) and the nuclear factor (NF)-kappaB pathway with diabetes-induced retinal inflammation. ⋯ The present data revealed significant a contribution of the AT1-R/NF-kappaB pathway to diabetes-induced retinal inflammation, providing a mechanistic reason for targeting AT1-R or NF-kappaB in the treatment of diabetic retinopathy.
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Invest. Ophthalmol. Vis. Sci. · Aug 2007
Randomized Controlled Trial Comparative StudyPhase 3 safety comparisons for 1.0% azithromycin in polymeric mucoadhesive eye drops versus 0.3% tobramycin eye drops for bacterial conjunctivitis.
To compare the safety and tolerability of 1.0% azithromycin in a polymeric mucoadhesive delivery system with 0.3% tobramycin ophthalmic solution for the treatment of bacterial conjunctivitis. ⋯ This is the first report of the safety and tolerability of a commercially manufactured preparation of azithromycin for ophthalmic use. Azithromycin 1% in DuraSite is safe and can be administered in a regimen of less frequent doses than can tobramycin, while producing an equivalent clinical outcome. The formulation is well tolerated in patients over the age of 1 year for the eradication of bacteria commonly associated with conjunctivitis. (ClinicalTrials.gov number, NCT00105469.).
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Invest. Ophthalmol. Vis. Sci. · Jul 2007
Involvement of the endocannabinoid system in retinal damage after high intraocular pressure-induced ischemia in rats.
To evaluate whether high intraocular pressure (IOP)-induced ischemia is associated with modifications in the retinal endocannabinoid metabolism and to ascertain whether drugs that interfere with the endocannabinoid system may prevent retinal damage due to ischemic insult. ⋯ The original observation that retinal ischemia-reperfusion reduces endogenous AEA via enhanced expression of FAAH supports the deduction that this is implicated in retinal cell loss caused by high IOP in the RGC layer.