No abstract

Human corneas were analyzed for glycosaminoglycans during various stages of embryonic development and at different postnatal ages. The development and aging of the cornea was accompanied by a transient increase of glycosaminoglycan hexosamine up to 2 years of age and thereafter by a stepwise decrease to a value which seemed to be constant in all age groups. Keratan sulphate formed a minor part of glycosaminoglycans in fetal, premature and newborn corneas but it predominated in older corneas. The development of the cornea was characterized by a decrease in sulphation of chondroitin sulphate. No hyaluronate was found in the fetal corneas available for this study.

No abstract

In spite of a standard lime burn technique, the injured rabbit eyes revealed a great variety of corneal damage with totally or partially denuded epithelium and stromal opacities of varying intensity. Irrigation of the eye with water removed more than half of the calcium from the cornea. A further significant decrease of the calcium level was achieved by the action of hydrophilic gel contact lens presoaked with a 1.85% ethylenediamine tetra acetate (EDTA) solution. The lime-burned cornea does not prevent intraocular penetration of EDTA from contact lens fitted on the injured eye. A delay of 1 or 2 h in application of EDTA contact lens after the lime burn and water irrigation of the eye seems to enhance permeation of the chelating agent into the cornea

Soft poly(hydroxyethylmethacrylate) gel contact lenses soaked with a solution containing either radioactive sulphate or D-glucose-¹⁴C were applied to the rabbit eyes for time intervals ranging from 10 min to 24 h. It was estimated that the radioactive substances were released very rapidly from the contact lens; about 90% within the first hour of application. Radioactivity was then detected in the cornea, aqueous humour, crystalline lens, and vitreous in amounts decreasing with the duration of the experiment. A stepwise accumulation of radioactivity in the eye tissues and fluids was observed with sulphate but not with glucose.