Binocular form deprivation influences the visual cortex

a-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors are considered to play a crucial role in synaptic plasticity in the developing visual cortex. In this study, we established a rat model of binocular form deprivation by suturing the rat binocular eyelids before eye-opening at postnatal day 14. During development, the decay time of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors of normal rats became longer after eye- opening; however, the decay time did not change significantly in binocular form deprivation rats. The peak value in the normal group became gradually larger with age, but there was no significant change in the binocular form deprivation group. These findings indicate that binocular form deprivation influences the properties of excitatory postsynaptic currents mediated by a-amino-3- hydroxy-5-methyl-4-isoxazolepropionic acid receptors in the rat visual cortex around the end of the critical period, indicating that form stimulation is associated with the experience-dependent modification of neuronal synapses in the visual cortex.

Effect of Topical FK506 Used alone or Combined with Keratoplasty on Patients with Recurrent Mooren′s Corneal Ulcer

Purpose: To evaluate the efficacy of topical 0.1% FK506 used alone or combined with keratoplasty on patients with recurrent Mooren′s ulcer. Methods: This is a retrospective interventional consecutive case series. Nine patients (15 eyes) with recurrent Mooren′s ulcer were treated with topical 0.1% FK506 alone or combined with keratoplasty. Two eyes with ulcers involving less than half the corneal limbus were treated with topical 0.1% FK506. Of the other 13 eyes with ulcers involving more than half the limbus, twelve were treated with excision of the ulcer and adjacent conjunctiva combined with lamellar keratoplasty. One eye with a central impending corneal perforation was treated with penetrating keratoplasty.Topical 0.1% FK506 was given post-operatively to all thirteen eyes after re-epithelia-lisation of the cornea. FK506 levels in the surgically resected cornea and conjunctiva of the operated eyes were measured using enzyme immunoassay procedures. Twelve patients (17 eyes) with recurrent Mooren′s ulcer treated with lamellar keratoplasty combined with topical 0.1% dexamethasone were taken as the control. The main measure of the outcome was the recurrence of Mooren′s ulcer in the patients. Results: Nine patients (15 eyes) with recurrent Mooren′s ulcer were all successfully treated. Vision in 5 eyes improved by two lines or better after treatment. No recurrence was observed during the follow up period of 12 to 22 months. After topical application of 0.1% FK506, concentrations of 30～350 ng/g of FK506 were found in the cornea and conjunctiva. Seven eyes of Mooren′s ulcer in the control group recurred during the follow up period. Conclusion: Topical 0.1% FK506 used alone or combined with keratoplasty is a safe and effective therapy for patients with recurrent Mooren′s ulcer.