Investigative ophthalmology & visual science
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Invest. Ophthalmol. Vis. Sci. · May 1999
Correlation of VEGF expression by leukocytes with the growth and regression of blood vessels in the rat cornea.
To determine the temporal and spatial relationships between neovascularization and basic fibroblast growth factor (bFGF) and vascular endothelial growth factor (VEGF) mRNA and protein expression in the rat cornea after cautery with silver nitrate. ⋯ VEGF production by leukocytes correlates temporally and spatially with cautery-induced angiogenesis in the rat cornea. Both inflammatory products and hypoxia appear to sufficiently increase VEGF expression near the cautery lesion to increase vascular permeability of limbal vessels and induce endothelial cell migration and proliferation.
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Invest. Ophthalmol. Vis. Sci. · Mar 1999
Electrical stimulation as a therapeutic option to improve eyelid function in chronic facial nerve disorders.
To establish whether it is possible to improve orbicularis oculi muscle function in the eyelids of patients with a chronic seventh cranial nerve palsy by using transcutaneous electrical stimulation to the point at which electrical stimulation induces a functional blink. ⋯ Electrical stimulation using transcutaneous electrical nerve stimulators units can improve voluntary eye closure, apparently because of a reduction in stiffness of eyelid mechanics, rather than an improvement of muscle function. Investigation of alternative stimulation regimens is warranted.
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Invest. Ophthalmol. Vis. Sci. · Mar 1999
Latrunculin-A causes mydriasis and cycloplegia in the cynomolgus monkey.
To determine the effect of latrunculin (LAT)-A, which binds to G-actin and disassembles actin filaments, on the pupil, accommodation, and isolated ciliary muscle (CM) contraction in monkeys. ⋯ In monkeys, LAT-A causes mydriasis and cycloplegia, perhaps related to its known ability to disrupt the actin microfilament network and consequently to affect cell contractility and adhesion. Effects of LAT-A on the iris and CM may have significant physiological and clinical implications.
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Invest. Ophthalmol. Vis. Sci. · Mar 1999
CNTF, not other trophic factors, promotes axonal regeneration of axotomized retinal ganglion cells in adult hamsters.
To investigate the in vivo effects of trophic factors on the axonal regeneration of axotomized retinal ganglion cells in adult hamsters. ⋯ Neurons of the adult central nervous system can regenerate in response to trophic supply after injury, and ciliary neurotrophic factor is at least one of the trophic factors that can promote axonal regeneration of axotomized RGCs.
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Invest. Ophthalmol. Vis. Sci. · Feb 1999
Suppression of NF-kappaB-dependent proinflammatory gene expression in human RPE cells by a proteasome inhibitor.
To determine whether nuclear transcription factor-kappaB (NF-kappaB) is activated in human retinal pigment epithelial (hRPE) cells in response to interleukin-1beta (IL-1beta), tumor necrosis factor-alpha (TNF-alpha), or interferon-gamma (IFN-gamma) alone or in combination and if so, whether expression of proinflammatory genes induced by these agents can be blocked by a proteasome inhibitor, MG-132, which inhibits the degradation of I kappaB, an NF-kappaB inhibitor, thereby preventing nuclear translocation of NF-kappaB. ⋯ TNF-alpha, IL-1beta, and TII induce expression of proinflammatory cytokines and ICAM-1 in hRPE cells through an NF-kappaB-dependent signal transduction pathway. This effect is blocked by MG-132, a proteasome inhibitor that prevents I kappaB degradation. Inhibition of NF-kappaB may be a useful strategy to treat proliferative vitreoretinopathy and uveitis, ocular diseases initiated and perpetuated by cytokine activation.