[Experimental validation of the developing a matrix based on decellularized vascular wall for subsequent substitution urethroplasty].

Urethral strictures are urgent urological problem. Anastomotic and substitution urethroplasty are the most effective treatments. For substitution urethroplasty, buccal mucosa is most often used. There are the following difficulties associated with the substitution urethroplasty: complications in the donor area, the lack of tissue for substitution, an additional incision, and increased timing of surgery due to the need to obtain a flap or graft. Tissue engineering can be useful in solving the above problems. Tissue engineering involves the use a matrix without cells and matrix with one or more types of cells (tissue-engineering designs). In our study we have evaluated the ability to create a matrix for the substitution urethroplasty in animal experiments. The decellularized cadaveric arterial wall was used as a matrix. Decellularization was performed using enzymatic method. At the first stage, we transplanted matrix fragments in interscapular region in rats. An extremely weak bioactivity dof decellularized matrix of cadaveric arterial wall (DMCAW) due to the low immunogenicity of the material was revealed. Thus resorption of DMCAW was quite slow (60-90 days). At the second stage, in an experiment on rabbits, substitution urethroplasty using tubular DMCAW was successfully performed. Intraoperative urethral defect up to 1.8 cm was created, which was replaced by a tubular DMCAW. The use of this type of matrix has showed good structural and functional results: urethral strictures did not arise, the rejection of the matrix was not observed. A slow degradation of the matrix and progressive epithelialization of onnective tissue capsule were revealed. Decellularized matrix based on cadaveric arterial wall can be considered as a material for substitution urethroplasty.

[Method of protecting of sutures in the stomach and intestines]. / Sposob zashchity shvov na zheludke i kishechnike.

The authors have developed and described the method for intraoperative prophylaxis of complications caused by incompetence of the sutures on the stomach and bowels. It consists in closure of the sutures along the line of contiguity by two-layers of compact-porous collagenous explants, which possess antibacterial properties, the period of resorption in abdominal cavity being 15-20 days. The characteristics of the explants are presented and their advantages compared to commonly used methods covering by pellicle or glue film peritonization by sero-muscular sutures. Application of collagenous explants from "Sanguicol" preparation in surgical treatment of 155 patients with external intestinal fistulas, compared to peritonization by sero-muscular sutures (66 patients), has demonstrated a high effectiveness of proposed explants in prevention of postoperative intraabdominal complications.

[Application hemostatic drug in capillary-parenchymatous bleeding]. / Applikatsionnoe sredstvo gemostaza pri kapilliarno-parenkhimatoznom krovotechenii.

Specific activity of a new hemostatic drug thrombocol was studied in experiments. Laboratory rabbits were used for management of experimental capillary-parenchymatous hemorrhage. The action of thrombocol was compared with hemostatic effect of other drugs: carbocol, combutek-2, super-4 (USA), collastipt (Germany), collagen sponge (Germany). It was found that thrombocol was highly hygroscopic, showed good adhesion to wounded surface, high plasticity and better hemostatic effect compared with other collagen-containing drugs.

[Collagen plastic surgery in progressive myopia]. / Primenenie operatsii kollagenoplastiki pri progressiruiushchei blizorukosti.

The technique of surgery is as follows: 4 implants of wetted and squeezed out collagen sponge, 7-8 x 20-22 mm in size, 2-2.5 mm thick, are introduced into Tenon's space to fill the gaps between the rectus muscles; a standard sterile hemostatic sponge or a colocyl sponge in employed. Experimental studies have shown the development of new episcleral connective tissue at the sites where the sponge has been introduced, the thickness of this tissue exceeding 1.5-2.5-fold that of the rabbit sclera. Altogether 200 eyes (100 patients) with myopia of 3.5-15 diopters have been operated on. Myopia progress has been stopped in 95% of cases; vision acuity has improved by 0.14-0.15 (p less than 0.001), clinical refraction has reduced by 0.9-1.0 diopters (p less than 0.001) in 84% of patients. A significant improvement of the hemodynamics has been achieved, as well as of the eye membrane rigidity (1.5-2-fold). The complications were only negligible diplopia early after surgery in 3 cases. Collagen plastic surgery is a simple method, marked for the availability of the implanted material; it is highly effective and in fact does not involve complications, this permitting its use in progressive myopia of more than 4.0-5.0 diopters.

[Effect of biologically active dressings of wounds on the course of the wound process]. / Vliianie biologicheski aktivnykh pereviazochnykh pokrytii ran na techenie ranevogo protsessa.

A comparative analysis of the effectiveness and expediency of the local application of collocyl (128 patients), trypsin immobilized on textile cellulose and kapron matrix (186 patients) and gauze bandage moistened with a solution of enzymes and 10% sodium chloride was made. It was shown that collocyl as well as trypsin modified gauze and kapron accelerated cleansing the wounds of nonviable tissues, decreased their infectivity, reduced intoxication of the organism and improved the course of the wound process.

[Treatment of suppurative wounds of soft tissues with colocyl and its combination with proteolytic enzymes]. / Lechenie gnoinykh ran miagkikh tkanei kolotsilom i ego sochetaniem s proteoliticheskimi fermentami.

The effect of a collagenous preparation Colocyl and its combination with proteolytic enzymes on the healing of soft tissue purulent wounds were studied in 239 patients. Colocyl and its combination with proteolytic enzymes were shown to facilitate the rejection of devitalized tissues, control of the inflammation and activation of reparative processes.

[Development and use of periodontal dressing of collagen and Lactobacillus casei 37 cell suspension in combined treatment of periodontal disease of inflammatory origin (a microbiological study)]. / Razrabotka i primenenie parodontal'noi poviazki iz kollagena i suspenzii kletok Lactobacillus casei 37 v kompleksnom lechenii vospalitel'nykh zabolevanii parodonta (rezul'taty mikrobiologicheskikh issledovanii).

Periodontal dressing consisting of collagen and Lactobacillus casei 37 cell suspension (cell concentration 108 cells/ml) was created and used in combined treatment of patients with chronic generalized parodontitis. Efficacy of the developed isolation was explained by a considerable decrease of the number and frequency of isolation of aggressive microbial representatives (pigment synthesizing Bacteroids, Actinomyces and Str. intermedius) in periodontal pockets and also Fungus (Candida albicans). This periodontal dressing provided remission up to 10-12 months.

[Gapkol--a new osteoplastic material]. / Gapkol--novyi osteoplasticheskii material.

Hapcol, a new osteoplastic material, representing a biological composition on the basis of a natural biopolymer collagen with biologically compatible osteotropic mineral hydroxyapatite has been developed and allowed for clinical use. It is intended for use in dentistry in surgical treatment of periodontal diseases, deformations of the abutment tissues of the face, filling of bone defects after cystectomy, surgery for bone plasty, etc. Hapcol is characterized by antiinflammatory action, stimulates repair osteogenesis and collagenogenesis. Joint stock company Polistom starts commercial manufacture of the new material.

[Mechanism of action of collagen on processes of regeneration]. / K voprosu o mekhanizme deistviia kollagena na protsessy regeneratsii.

The effect of collagen, its hydrolysate and glycin on metabolism of cyclic nucleotides in wound tissue was studied in experiments on animals. Collagen was found to reduce the cAMP level in muscles of the wound fundus, while the concentration of cGMP remained unchanged. Collagen hydrolysate induced unidirectional changes in cyclic nucleotides, whereas glycin opposite ones. The basal activity of cAMP phosphodiesterase was not changed. The mechanism of the stimulatory effect of collagen on wound healing is discussed.

[Experimental premises and 1st experiences in the clinical use of antibacterial vascular prostheses under circumstances of increased risk of suppuration]. / Eksperimental'nye predposylki i pervyi opyt klinicheskogo primeneniia antibakterial'nykh sosudistykh protezov v usloviiakh povyshennogo riska nagnoeniia.

It was shown on the basis of laboratory and experimental data that created antibacterial vascular prostheses are marked, on the main, by local bacteriostatic and anticoagulative effect. It was found that heparin concentration of 3 to 500 U per 1 kg collagen causes a hyperadhesive effect on blood platelets and facilitates the formation of the primary thrombocytic thrombus. The free surface energy grows in this case from 34 +/- 0.8 to 66.3 +/- erg/cm2. The optimal thromboresistant effect occurs in heparin content of 1 U per 1 mg collagen. That this choice is correct is confirmed on examination of the inner surface of the prostheses with an electron microscope after being in the blood flow for 45 minutes. Bifurcation and linear antibacterial prostheses were used in 9 patients with a high risk of suppuration verified by cultures of discharge from ulcers and lymph nodes, and the presence of lymphangitis and lymphadenitis. The effect was positive in 8 patients, 2 of them had superficial suppuration of the operative wounds.

[The effect of chondroitin sulfate preparations on wound healing and the strength of the surgical scar]. / Vliianie preparatov khondroitinsul'fata na zazhivlenie ran i prochnost' khirurgicheskogo rubtsa.

An experimental investigation of the ability of the chondroitinsulphate preparation produced from cattle tracheas, of rumalon and chonsuride to stimulate the regeneration of cutaneous coverings in case of their injury was carried out. A strength of the surgical cicatrix and its elongation at rupture in two weeks' injections of chondroitinsulphate increased in comparison with control. A stimulating effect of chondroitinsulphate to regeneration of flesh wound in case of local single action didn't differ essentially from the effect of chonsuride. In case of application of the preparations, an area of wound for the rats received chondroitinsulphate was already on the eighth day twice as less in comparison with the animals treated with chonsuride. Thus, a stimulating effect of chondroitinsulphate preparation to the regeneration of damaged cutaneous coverings by both parenteral and local administration was shown.