Influence of decorative lenses on higher-order wavefront aberrations.

PURPOSE: To investigate the influence of decorative lenses on ocular wavefront aberrations. METHODS: A wavefront analyzer was used to measure higher-order aberrations (HOAs) in 20 right eyes of 20 participants while they were wearing Vistacon contact lenses of different designs, namely, clear 1-day Acuvue, ring-design circle 1-day Acuvue Define (Accent style), or spoke-design circle 1-day Acuvue Define (Vivid style). All of these lenses are made of the same materials and have the same lens parameters, except for the tinted design. HOAs induced by each contact lens were measured for 4- and 6-mm pupils. The coma-like, spherical-like, and total HOAs of each lens type were compared. HOAs of well- and poorly fitting lenses were also compared. RESULTS: For a 4-mm pupil, the HOAs of the three lens types did not differ significantly. For the 6-mm pupil, coma-like and total HOAs were significantly larger with decorative lenses than with clear lenses (P < 0.05, Bonferroni test). No significant differences were observed between the two types of decorative lenses. Poorly fitting decorative lenses showed significantly larger HOAs than did well-fitting decorative lenses. CONCLUSIONS: Poorly fitting decorative lenses may reduce the quality of vision. Consequently, care should be taken that these lenses are properly centered.

The Rho-kinase inhibitor fasudil restores normal motor nerve conduction velocity in diabetic rats by assuring the proper localization of adhesion-related molecules in myelinating Schwann cells.

The Rho/Rho-kinase signaling pathway has been shown to be involved in the complications of diabetes. In this study, we found that fasudil, a specific Rho-kinase inhibitor, had a beneficial effect on the motor nerve conduction velocity (MNCV), which is delayed in rats with streptozotocin (STZ)-induced diabetes. Cadherin-dependent adherens junctions (AJs) in myelinating Schwann cells, necessary for proper myelin formation and rapid propagation of action potentials, are regulated by Rho/Rho-kinase signaling. These AJ structures are maintained by E-cadherin and catenin complexes such as ß-catenin and p120 catenin. To elucidate the mechanism underlying the effect of fasudil on MNCV, we examined alterations in AJ structure in the peripheral nerves of the experimental rats. Our results showed that the activities of Rho and Rho-kinase increased simultaneously in the sciatic nerves of the diabetic rats. Fasudil restored the MNCV by suppressing the up-regulation of the Rho-kinase. In the diabetic state, enhanced Rho and Rho-kinase activity reduced p120 catenin expression and altered the distribution of p120 catenin and E-cadherin, which are normally localized in the paranodal compartment of the nodes of Ranvier and Schmidt-Lanterman incisures where autotypic AJs stabilize myelin structure. Fasudil restored normal p120 catenin expression and the distribution of p120 catenin and E-cadherin in the myelin sheath. In conclusion, reduced expression and altered distribution of the adhesion molecules in the myelin sheath might contribute to the slowing of the MNCV in the diabetic rats. Fasudil, through its effect on the distribution of the adhesion-related molecules, might prevent slowing of the MNCV.