[Use of Bioimplants to Replace Cartilage Part II: Application of Implants in Animal Experiments.].

The published paper pertains to a group of fullgrown minipigs where under anaesthesia with Narcamone after premedication with Rometar cartilage samples from the medial condyle of the femur in the area of the femoropatellar joint were taken. The collected cartilage samples served subsequently for the preparation of an autologous implant. After its preparation another operation was performed where by means of a bioptic trocar (diameter 3.

Morphological features of bone healing under the effect of collagen-graft-glycosaminoglycan copolymer supplemented with the tripeptide Gly-His-Lys.

The authors prepared 7.5% and 12.5% collagen gel, and supplemented it with the tripeptide Gly-His-Lys (GHK), perfloxacine and hypersulphated glycosaminoglycan (HSGAG).

[Tracheal replacement with a swine prosthesis].

In 12 experimental operations the authors tested the biocompatibility of a xenologous trachea from a pig which was used to replace a 5 cm defect of the trachea in a dog. After special preparation eliminating the antigenicity of the pig trachea the thus prepared graft was sutured into the thoracic portion of the dog trachea. The experiment could not be evaluated in two instances because the dog died on the operating table.

[The effect of collagenous gel on endoprosthesis anchoring.].

Collagen supplemented with tripeptide (gly-his-lys) was tested for implantation of cervicocapital endoprostheses of the hip in adult minipigs. In anaesthesia bone marrow cavity was filled up with the collagenous gel and then one of the two endoprosthesis types, produced by BMT Poldi Kladno was implanted. The experimental animals were killed eight, nine and ten weeks after operation.

[The role of collagen implants containing the tripeptide gly-his-lys in bone healing process.].

The authors prepared 12,5% collagen gel, that they supplemented by tripeptide gly-his-lys. peflacin and hypersulfated glycosaminoglycan (HSGAG). By means of I125 marking they followed up its absorption from small polyurethan sponges placed under the skin of rats.

Reactivity and the fate of some composite bioimplants based on collagen in connective tissue.

Three composite materials based on collagen gel prepared with ISC40 and supplemented with the tripeptide glycine-histidine-lysine (GHK) mixed with bioglass (BAS O), pure hydroxyapatite (grain: 0.5-1.0 microns and 13-23 microns) and shredded beef bone were tested in the laboratory rat and guinea-pig.

[A tracheal prosthesis made from P(AEMA)--a further step toward tracheal replacement].

In animal experiments (5 dogs) the authors tested a material for the construction of tracheal prostheses so far not used in other countries. P(AEMA), the polymer 2-acetoxy-ethylmethacrylate is well tolerated, it did not produce a rejection reaction. The inner wall of the prosthesis was throughout the experiment patent, smooth and secretion did not adhere to it.

[Replacement of the trachea with a prosthesis--an unsolvable problem?].

Reconstruction of the trachea by means of a segmental prosthesis is a complicated problem, which has not been completely resolved so far. The authors present a brief historical review of attempts to bridge the gap by different types of prostheses Evon Neville's silicone prostheses are not well tolerated on a long-term basis and its is thus important to look for other materials for the manufacture of an "ideal" tracheal prosthesis. (ur synthetic prosthesis made from poly/ARMA/is very well tolerated, similarly as silicone prostheses.

[Prosthesis of ligament by specially treated collagenous tissue.].

Artificial prostheses of ligaments are associated with many problems. At first they take over the function of the ligament, later however their strength declines. Therefore at present collagen autotransplants are prefered.

[Collagen - its use as a biomaterial in orthopedics.].

Collagen structure and its biological properties' esp. its effect on cell proliferation and differentiation, on aggregation of thrombocytes and its antigenicity are described. Further properties of collagen as biomaterial are discussed.

Elastogenesis in the wall of the human thoracic aorta.

The results of this study dealing with the human thoracic foetal aorta testify that even in the middle of the fifth month of development the internal elastic membrane is not yet completely continuous. Furthermore they show that elastogenesis in the tunica media of the human thoracic aorta does not begin directly below the internal elastic membrane, as it does in the foetal aorta of the laboratory rat, but, as it can be seen in our material, somewhat deeper in the developing tunica media. A thin layer of less differentiated tunica media cells persists for a long time in the vicinity of the internal elastic membrane.