Investigative ophthalmology & visual science
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Invest. Ophthalmol. Vis. Sci. · Jul 2011
Blunt eye trauma: empirical histopathologic paintball impact thresholds in fresh mounted porcine eyes.
Ballistic studies were conducted using gelatin-embedded abattoir-fresh porcine eyes suspended within clear acrylic orbits to discern the energy required to produce specific ocular injuries. Paintball impact provides a robust ballistic model for isolating and quantifying the role of direct blunt force in ocular trauma. ⋯ Impact thresholds correlating traumatic ocular pathology with impact energy followed a positive stepwise progression in severity with impact energies between 2 and 10 joules. Moderate angle recession commensurate with typical clinical traumatic glaucoma was not observed among control eyes, but occurred at relatively low impact energy of 3.5 joules among test eyes. Extensive disruption in and around the angle (iridodialysis/cyclodialysis) consistently occurred at energies >7 joules. Globe rupture required a minimum energy of 10 joules.
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Invest. Ophthalmol. Vis. Sci. · Jul 2011
Ghrelin modulates physiologic and pathologic retinal angiogenesis through GHSR-1a.
Vascular degeneration and the ensuing abnormal vascular proliferation are central to proliferative retinopathies. Given the metabolic discordance associated with these diseases, the authors explored the role of ghrelin and its growth hormone secretagogue receptor 1a (GHSR-1a) in proliferative retinopathy. ⋯ New roles were disclosed for the ghrelin-GHSR-1a pathway in the preservation of retinal vasculature during the vaso-obliterative phase of OIR and during the angiogenic phase of OIR. These findings suggest that the ghrelin-GHSR-1a pathway can exert opposing effects on retinal vasculature, depending on the phase of retinopathy, and thus holds therapeutic potential for proliferative retinopathies.
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Invest. Ophthalmol. Vis. Sci. · Jun 2011
Comparative StudyA lipid nanoparticle system improves siRNA efficacy in RPE cells and a laser-induced murine CNV model.
To explore the possibility of the PEGylated liposome-protamine-hyaluronic acid nanoparticles (PEG-LPH-NP) loaded with siRNA (PEG-LPH-NP-S) in ARPE19 cells and a laser-induced rat model for the treatment of choroidal neovascularization (CNV). ⋯ PEG-LPH-NP may be a promising lipid nanoparticle system for the siRNA treatment of CNV.
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Invest. Ophthalmol. Vis. Sci. · May 2011
Cone photoreceptor abnormalities correlate with vision loss in patients with Stargardt disease.
PURPOSE. To study the relationship between macular cone structure, fundus autofluorescence (AF), and visual function in patients with Stargardt disease (STGD). METHODS. ⋯ CONCLUSIONS. AOSLO imaging demonstrated abnormal cone spacing in regions of abnormal fundus AF and reduced visual function. These findings provide support for a model of disease progression in which lipofuscin accumulation results in homogeneously increased AF with cone spacing abnormalities, followed by heterogeneously increased AF with cone loss, then reduced AF with cone and RPE cell death.