[In vitro and in vivo physicochemical study of depot formation of cinchocaine in an atelocollagen matrix]. / Fyzikálne chemické in vitro a in vivo studium depotizace cinchokainu v atelokolagenové plsti.

The paper presents an introductory physicochemical study dealing with the preparation of atelocollagen felt saturated with local anesthetics, with the modelling of the release of the anesthetic from the collagen matrix in vitro, and with the checking of the corresponding analytical procedures (dc-polarography and UV-VIS spectrophotometry) for the determination of cinchocaine. The study is supplemented with experiments in vivo that confirm the usability of the new material for the depot formation of local anesthetics.

[Effect of infrared rays on the eye in progressive myopia]. / Vliv infracerveného zárení na oko s progresivní krátkozrakostí.

In the submitted paper the authors pay attention to infrared radiation close to visible light is intensely absorbed by haemoglobin, melanin and xanthophyll whereby part of the radiation energy is transformed into heat. The authors present three series of experiments where they investigated by different methods changes in the vitreous body after exposure to light, infrared radiation or raised temperature. They assume that on the defocused eye with a myopic conus which developed as a result of an inborn inadequate closure of the optic cup the light can cause a rise of temperature in the vitreous body. This leads to metabolic changes characterized by increased activity of lysosomal enzymes causing loss of the spatial structure of hyaluronic acid and collagen biomolecules. Penetration of the altered vitreous fluid thought the conus can lead to degradation of the interstitial substances of the sclera. Suitable absorption glasses filtering infrared light close to visible light could reduce the hyperthermia of the vitreous body.

Scleroplasty in progressive myopia--selection of materials.

Scleroplastic surgery is known to encounter the pathogenetical agent when the progressive myopia develops. In the first part, the implemented surgical approaches as well as up-to-date surgical techniques are presented. The experimental part is reserved for the selection of material which is necessary to perform scleroplasties. Both the allogenic and xenogenic grafts have been studied for histocompatibility on 20 rabbits. Following materials were used: 2 types of collagenic sponge, native and deproteinated human sclera, modified dura mater as well as both the native and devitalized sclera from rabbits. The best results were obtained with allogenic sclera, deproteinated xenogenic sclera and collagenic sponge. The application of other materials is discussed.