Investigative ophthalmology & visual science
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Invest. Ophthalmol. Vis. Sci. · Oct 2004
Reading performance in patients with retinitis pigmentosa: a study using the MNREAD charts.
To evaluate the relationship between reading performance and severity of disease in patients with retinitis pigmentosa (RP), assessed with routine clinical psychophysical visual tests. ⋯ The reading performance of most patients with RP is only moderately impaired. It correlates with contrast sensitivity, visual acuity, and visual field. It should be assessed in all cases, as disability can ensue, even when visual acuity is preserved. In patients with RP with poor reading performance, there is little potential for high-magnification devices because visual field constriction affects the reading rate.
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Invest. Ophthalmol. Vis. Sci. · Oct 2004
Phosphatidylinositol 3-kinase (PI-3K)/Akt but not PI-3K/p70 S6 kinase signaling mediates IGF-1-promoted lens epithelial cell survival.
To investigate the ability of insulin-like growth factor (IGF)-1 to prevent apoptosis in lens epithelial cells and the involvement of phosphatidylinositol 3-kinase (PI-3K)/Akt and PI-3K/p70 S6 kinase (p70 S6K) signaling in the cell-survival process. ⋯ These studies demonstrated a role for IGF-1 in the prevention of the lens epithelial cell apoptosis process. Furthermore, these studies indicated that anti-apoptotic and proliferative signals from IGF-1 bifurcate downstream of PI-3K. Whereas IGF-1-mediated PI-3K/Akt signaling plays a pivotal role in cell survival by inactivating proapoptotic Bad protein and suppressing caspase activation, its stimulation of the PI-3K/p70 S6K cascade promotes proliferation.